head 1.1; branch 1.1.1; access; symbols netbsd-11-0-RC4:1.1.1.10 netbsd-11-0-RC3:1.1.1.10 netbsd-11-0-RC2:1.1.1.10 netbsd-11-0-RC1:1.1.1.10 perseant-exfatfs-base-20250801:1.1.1.10 netbsd-11:1.1.1.10.0.10 netbsd-11-base:1.1.1.10 netbsd-10-1-RELEASE:1.1.1.10 perseant-exfatfs-base-20240630:1.1.1.10 perseant-exfatfs:1.1.1.10.0.8 perseant-exfatfs-base:1.1.1.10 netbsd-8-3-RELEASE:1.1.1.7 netbsd-9-4-RELEASE:1.1.1.9 netbsd-10-0-RELEASE:1.1.1.10 netbsd-10-0-RC6:1.1.1.10 netbsd-10-0-RC5:1.1.1.10 netbsd-10-0-RC4:1.1.1.10 netbsd-10-0-RC3:1.1.1.10 netbsd-10-0-RC2:1.1.1.10 netbsd-10-0-RC1:1.1.1.10 netbsd-10:1.1.1.10.0.6 netbsd-10-base:1.1.1.10 netbsd-9-3-RELEASE:1.1.1.9 cjep_sun2x:1.1.1.10.0.4 cjep_sun2x-base:1.1.1.10 cjep_staticlib_x-base1:1.1.1.10 netbsd-9-2-RELEASE:1.1.1.9 cjep_staticlib_x:1.1.1.10.0.2 cjep_staticlib_x-base:1.1.1.10 netbsd-9-1-RELEASE:1.1.1.9 phil-wifi-20200421:1.1.1.10 phil-wifi-20200411:1.1.1.10 phil-wifi-20200406:1.1.1.10 netbsd-8-2-RELEASE:1.1.1.7 netbsd-9-0-RELEASE:1.1.1.9 netbsd-9-0-RC2:1.1.1.9 netbsd-9-0-RC1:1.1.1.9 netbsd-9:1.1.1.9.0.2 netbsd-9-base:1.1.1.9 phil-wifi-20190609:1.1.1.9 netbsd-8-1-RELEASE:1.1.1.7 netbsd-8-1-RC1:1.1.1.7 pgoyette-compat-merge-20190127:1.1.1.8.2.1 pgoyette-compat-20190127:1.1.1.9 pgoyette-compat-20190118:1.1.1.9 pgoyette-compat-1226:1.1.1.9 pgoyette-compat-1126:1.1.1.9 pgoyette-compat-1020:1.1.1.9 pgoyette-compat-0930:1.1.1.9 pgoyette-compat-0906:1.1.1.9 netbsd-7-2-RELEASE:1.1.1.4.2.1 pgoyette-compat-0728:1.1.1.9 clang-337282:1.1.1.9 netbsd-8-0-RELEASE:1.1.1.7 phil-wifi:1.1.1.8.0.4 phil-wifi-base:1.1.1.8 pgoyette-compat-0625:1.1.1.8 netbsd-8-0-RC2:1.1.1.7 pgoyette-compat-0521:1.1.1.8 pgoyette-compat-0502:1.1.1.8 pgoyette-compat-0422:1.1.1.8 netbsd-8-0-RC1:1.1.1.7 pgoyette-compat-0415:1.1.1.8 pgoyette-compat-0407:1.1.1.8 pgoyette-compat-0330:1.1.1.8 pgoyette-compat-0322:1.1.1.8 pgoyette-compat-0315:1.1.1.8 netbsd-7-1-2-RELEASE:1.1.1.4.2.1 pgoyette-compat:1.1.1.8.0.2 pgoyette-compat-base:1.1.1.8 netbsd-7-1-1-RELEASE:1.1.1.4.2.1 clang-319952:1.1.1.8 matt-nb8-mediatek:1.1.1.7.0.10 matt-nb8-mediatek-base:1.1.1.7 clang-309604:1.1.1.8 perseant-stdc-iso10646:1.1.1.7.0.8 perseant-stdc-iso10646-base:1.1.1.7 netbsd-8:1.1.1.7.0.6 netbsd-8-base:1.1.1.7 prg-localcount2-base3:1.1.1.7 prg-localcount2-base2:1.1.1.7 prg-localcount2-base1:1.1.1.7 prg-localcount2:1.1.1.7.0.4 prg-localcount2-base:1.1.1.7 pgoyette-localcount-20170426:1.1.1.7 bouyer-socketcan-base1:1.1.1.7 pgoyette-localcount-20170320:1.1.1.7 netbsd-7-1:1.1.1.4.2.1.0.6 netbsd-7-1-RELEASE:1.1.1.4.2.1 netbsd-7-1-RC2:1.1.1.4.2.1 clang-294123:1.1.1.7 netbsd-7-nhusb-base-20170116:1.1.1.4.2.1 bouyer-socketcan:1.1.1.7.0.2 bouyer-socketcan-base:1.1.1.7 clang-291444:1.1.1.7 pgoyette-localcount-20170107:1.1.1.6 netbsd-7-1-RC1:1.1.1.4.2.1 pgoyette-localcount-20161104:1.1.1.6 netbsd-7-0-2-RELEASE:1.1.1.4.2.1 localcount-20160914:1.1.1.6 netbsd-7-nhusb:1.1.1.4.2.1.0.4 netbsd-7-nhusb-base:1.1.1.4.2.1 clang-280599:1.1.1.6 pgoyette-localcount-20160806:1.1.1.6 pgoyette-localcount-20160726:1.1.1.6 pgoyette-localcount:1.1.1.6.0.2 pgoyette-localcount-base:1.1.1.6 netbsd-7-0-1-RELEASE:1.1.1.4.2.1 clang-261930:1.1.1.6 netbsd-7-0:1.1.1.4.2.1.0.2 netbsd-7-0-RELEASE:1.1.1.4.2.1 netbsd-7-0-RC3:1.1.1.4.2.1 netbsd-7-0-RC2:1.1.1.4.2.1 netbsd-7-0-RC1:1.1.1.4.2.1 clang-237755:1.1.1.5 clang-232565:1.1.1.5 clang-227398:1.1.1.5 tls-maxphys-base:1.1.1.4 tls-maxphys:1.1.1.4.0.4 netbsd-7:1.1.1.4.0.2 netbsd-7-base:1.1.1.4 clang-215315:1.1.1.4 clang-209886:1.1.1.3 yamt-pagecache:1.1.1.2.0.4 yamt-pagecache-base9:1.1.1.2 tls-earlyentropy:1.1.1.2.0.2 tls-earlyentropy-base:1.1.1.3 riastradh-xf86-video-intel-2-7-1-pre-2-21-15:1.1.1.2 riastradh-drm2-base3:1.1.1.2 clang-202566:1.1.1.2 clang-201163:1.1.1.2 clang-199312:1.1.1.2 clang-198450:1.1.1.2 clang-196603:1.1.1.1 clang-195771:1.1.1.1 LLVM:1.1.1; locks; strict; comment @// @; 1.1 date 2013.11.28.14.14.53; author joerg; state Exp; branches 1.1.1.1; next ; commitid ow8OybrawrB1f3fx; 1.1.1.1 date 2013.11.28.14.14.53; author joerg; state Exp; branches; next 1.1.1.2; commitid ow8OybrawrB1f3fx; 1.1.1.2 date 2014.01.05.15.38.14; author joerg; state Exp; branches 1.1.1.2.2.1 1.1.1.2.4.1; next 1.1.1.3; commitid wh3aCSIWykURqWjx; 1.1.1.3 date 2014.05.30.18.14.40; author joerg; state Exp; branches; next 1.1.1.4; commitid 8q0kdlBlCn09GACx; 1.1.1.4 date 2014.08.10.17.08.36; author joerg; state Exp; branches 1.1.1.4.2.1 1.1.1.4.4.1; next 1.1.1.5; commitid N85tXAN6Ex9VZPLx; 1.1.1.5 date 2015.01.29.19.57.31; author joerg; state Exp; branches; next 1.1.1.6; commitid mlISSizlPKvepX7y; 1.1.1.6 date 2016.02.27.22.12.08; author joerg; state Exp; branches 1.1.1.6.2.1; next 1.1.1.7; commitid tIimz3oDlh1NpBWy; 1.1.1.7 date 2017.01.11.10.33.25; author joerg; state Exp; branches; next 1.1.1.8; commitid CNnUNfII1jgNmxBz; 1.1.1.8 date 2017.08.01.19.35.23; 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author pgoyette; state Exp; branches; next ; commitid jjw7cAwgyKq7RfKz; 1.1.1.8.2.1 date 2018.07.28.04.33.17; author pgoyette; state Exp; branches; next ; commitid 1UP1xAIUxv1ZgRLA; 1.1.1.8.4.1 date 2019.06.10.21.45.21; author christos; state Exp; branches; next 1.1.1.8.4.2; commitid jtc8rnCzWiEEHGqB; 1.1.1.8.4.2 date 2020.04.13.07.46.32; author martin; state dead; branches; next ; commitid X01YhRUPVUDaec4C; desc @@ 1.1 log @Initial revision @ text @//===--- CGExprConstant.cpp - Emit LLVM Code from Constant Expressions ----===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This contains code to emit Constant Expr nodes as LLVM code. // //===----------------------------------------------------------------------===// #include "CodeGenFunction.h" #include "CGCXXABI.h" #include "CGObjCRuntime.h" #include "CGRecordLayout.h" #include "CodeGenModule.h" #include "clang/AST/APValue.h" #include "clang/AST/ASTContext.h" #include "clang/AST/RecordLayout.h" #include "clang/AST/StmtVisitor.h" #include "clang/Basic/Builtins.h" #include "llvm/IR/Constants.h" #include "llvm/IR/DataLayout.h" #include "llvm/IR/Function.h" #include "llvm/IR/GlobalVariable.h" using namespace clang; using namespace CodeGen; //===----------------------------------------------------------------------===// // ConstStructBuilder //===----------------------------------------------------------------------===// namespace { class ConstStructBuilder { CodeGenModule &CGM; CodeGenFunction *CGF; bool Packed; CharUnits NextFieldOffsetInChars; CharUnits LLVMStructAlignment; SmallVector Elements; public: static llvm::Constant *BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, InitListExpr *ILE); static llvm::Constant *BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, const APValue &Value, QualType ValTy); private: ConstStructBuilder(CodeGenModule &CGM, CodeGenFunction *CGF) : CGM(CGM), CGF(CGF), Packed(false), NextFieldOffsetInChars(CharUnits::Zero()), LLVMStructAlignment(CharUnits::One()) { } void AppendField(const FieldDecl *Field, uint64_t FieldOffset, llvm::Constant *InitExpr); void AppendBytes(CharUnits FieldOffsetInChars, llvm::Constant *InitCst); void AppendBitField(const FieldDecl *Field, uint64_t FieldOffset, llvm::ConstantInt *InitExpr); void AppendPadding(CharUnits PadSize); void AppendTailPadding(CharUnits RecordSize); void ConvertStructToPacked(); bool Build(InitListExpr *ILE); void Build(const APValue &Val, const RecordDecl *RD, bool IsPrimaryBase, const CXXRecordDecl *VTableClass, CharUnits BaseOffset); llvm::Constant *Finalize(QualType Ty); CharUnits getAlignment(const llvm::Constant *C) const { if (Packed) return CharUnits::One(); return CharUnits::fromQuantity( CGM.getDataLayout().getABITypeAlignment(C->getType())); } CharUnits getSizeInChars(const llvm::Constant *C) const { return CharUnits::fromQuantity( CGM.getDataLayout().getTypeAllocSize(C->getType())); } }; void ConstStructBuilder:: AppendField(const FieldDecl *Field, uint64_t FieldOffset, llvm::Constant *InitCst) { const ASTContext &Context = CGM.getContext(); CharUnits FieldOffsetInChars = Context.toCharUnitsFromBits(FieldOffset); AppendBytes(FieldOffsetInChars, InitCst); } void ConstStructBuilder:: AppendBytes(CharUnits FieldOffsetInChars, llvm::Constant *InitCst) { assert(NextFieldOffsetInChars <= FieldOffsetInChars && "Field offset mismatch!"); CharUnits FieldAlignment = getAlignment(InitCst); // Round up the field offset to the alignment of the field type. CharUnits AlignedNextFieldOffsetInChars = NextFieldOffsetInChars.RoundUpToAlignment(FieldAlignment); if (AlignedNextFieldOffsetInChars > FieldOffsetInChars) { assert(!Packed && "Alignment is wrong even with a packed struct!"); // Convert the struct to a packed struct. ConvertStructToPacked(); AlignedNextFieldOffsetInChars = NextFieldOffsetInChars; } if (AlignedNextFieldOffsetInChars < FieldOffsetInChars) { // We need to append padding. AppendPadding(FieldOffsetInChars - NextFieldOffsetInChars); assert(NextFieldOffsetInChars == FieldOffsetInChars && "Did not add enough padding!"); AlignedNextFieldOffsetInChars = NextFieldOffsetInChars; } // Add the field. Elements.push_back(InitCst); NextFieldOffsetInChars = AlignedNextFieldOffsetInChars + getSizeInChars(InitCst); if (Packed) assert(LLVMStructAlignment == CharUnits::One() && "Packed struct not byte-aligned!"); else LLVMStructAlignment = std::max(LLVMStructAlignment, FieldAlignment); } void ConstStructBuilder::AppendBitField(const FieldDecl *Field, uint64_t FieldOffset, llvm::ConstantInt *CI) { const ASTContext &Context = CGM.getContext(); const uint64_t CharWidth = Context.getCharWidth(); uint64_t NextFieldOffsetInBits = Context.toBits(NextFieldOffsetInChars); if (FieldOffset > NextFieldOffsetInBits) { // We need to add padding. CharUnits PadSize = Context.toCharUnitsFromBits( llvm::RoundUpToAlignment(FieldOffset - NextFieldOffsetInBits, Context.getTargetInfo().getCharAlign())); AppendPadding(PadSize); } uint64_t FieldSize = Field->getBitWidthValue(Context); llvm::APInt FieldValue = CI->getValue(); // Promote the size of FieldValue if necessary // FIXME: This should never occur, but currently it can because initializer // constants are cast to bool, and because clang is not enforcing bitfield // width limits. if (FieldSize > FieldValue.getBitWidth()) FieldValue = FieldValue.zext(FieldSize); // Truncate the size of FieldValue to the bit field size. if (FieldSize < FieldValue.getBitWidth()) FieldValue = FieldValue.trunc(FieldSize); NextFieldOffsetInBits = Context.toBits(NextFieldOffsetInChars); if (FieldOffset < NextFieldOffsetInBits) { // Either part of the field or the entire field can go into the previous // byte. assert(!Elements.empty() && "Elements can't be empty!"); unsigned BitsInPreviousByte = NextFieldOffsetInBits - FieldOffset; bool FitsCompletelyInPreviousByte = BitsInPreviousByte >= FieldValue.getBitWidth(); llvm::APInt Tmp = FieldValue; if (!FitsCompletelyInPreviousByte) { unsigned NewFieldWidth = FieldSize - BitsInPreviousByte; if (CGM.getDataLayout().isBigEndian()) { Tmp = Tmp.lshr(NewFieldWidth); Tmp = Tmp.trunc(BitsInPreviousByte); // We want the remaining high bits. FieldValue = FieldValue.trunc(NewFieldWidth); } else { Tmp = Tmp.trunc(BitsInPreviousByte); // We want the remaining low bits. FieldValue = FieldValue.lshr(BitsInPreviousByte); FieldValue = FieldValue.trunc(NewFieldWidth); } } Tmp = Tmp.zext(CharWidth); if (CGM.getDataLayout().isBigEndian()) { if (FitsCompletelyInPreviousByte) Tmp = Tmp.shl(BitsInPreviousByte - FieldValue.getBitWidth()); } else { Tmp = Tmp.shl(CharWidth - BitsInPreviousByte); } // 'or' in the bits that go into the previous byte. llvm::Value *LastElt = Elements.back(); if (llvm::ConstantInt *Val = dyn_cast(LastElt)) Tmp |= Val->getValue(); else { assert(isa(LastElt)); // If there is an undef field that we're adding to, it can either be a // scalar undef (in which case, we just replace it with our field) or it // is an array. If it is an array, we have to pull one byte off the // array so that the other undef bytes stay around. if (!isa(LastElt->getType())) { // The undef padding will be a multibyte array, create a new smaller // padding and then an hole for our i8 to get plopped into. assert(isa(LastElt->getType()) && "Expected array padding of undefs"); llvm::ArrayType *AT = cast(LastElt->getType()); assert(AT->getElementType()->isIntegerTy(CharWidth) && AT->getNumElements() != 0 && "Expected non-empty array padding of undefs"); // Remove the padding array. NextFieldOffsetInChars -= CharUnits::fromQuantity(AT->getNumElements()); Elements.pop_back(); // Add the padding back in two chunks. AppendPadding(CharUnits::fromQuantity(AT->getNumElements()-1)); AppendPadding(CharUnits::One()); assert(isa(Elements.back()) && Elements.back()->getType()->isIntegerTy(CharWidth) && "Padding addition didn't work right"); } } Elements.back() = llvm::ConstantInt::get(CGM.getLLVMContext(), Tmp); if (FitsCompletelyInPreviousByte) return; } while (FieldValue.getBitWidth() > CharWidth) { llvm::APInt Tmp; if (CGM.getDataLayout().isBigEndian()) { // We want the high bits. Tmp = FieldValue.lshr(FieldValue.getBitWidth() - CharWidth).trunc(CharWidth); } else { // We want the low bits. Tmp = FieldValue.trunc(CharWidth); FieldValue = FieldValue.lshr(CharWidth); } Elements.push_back(llvm::ConstantInt::get(CGM.getLLVMContext(), Tmp)); ++NextFieldOffsetInChars; FieldValue = FieldValue.trunc(FieldValue.getBitWidth() - CharWidth); } assert(FieldValue.getBitWidth() > 0 && "Should have at least one bit left!"); assert(FieldValue.getBitWidth() <= CharWidth && "Should not have more than a byte left!"); if (FieldValue.getBitWidth() < CharWidth) { if (CGM.getDataLayout().isBigEndian()) { unsigned BitWidth = FieldValue.getBitWidth(); FieldValue = FieldValue.zext(CharWidth) << (CharWidth - BitWidth); } else FieldValue = FieldValue.zext(CharWidth); } // Append the last element. Elements.push_back(llvm::ConstantInt::get(CGM.getLLVMContext(), FieldValue)); ++NextFieldOffsetInChars; } void ConstStructBuilder::AppendPadding(CharUnits PadSize) { if (PadSize.isZero()) return; llvm::Type *Ty = CGM.Int8Ty; if (PadSize > CharUnits::One()) Ty = llvm::ArrayType::get(Ty, PadSize.getQuantity()); llvm::Constant *C = llvm::UndefValue::get(Ty); Elements.push_back(C); assert(getAlignment(C) == CharUnits::One() && "Padding must have 1 byte alignment!"); NextFieldOffsetInChars += getSizeInChars(C); } void ConstStructBuilder::AppendTailPadding(CharUnits RecordSize) { assert(NextFieldOffsetInChars <= RecordSize && "Size mismatch!"); AppendPadding(RecordSize - NextFieldOffsetInChars); } void ConstStructBuilder::ConvertStructToPacked() { SmallVector PackedElements; CharUnits ElementOffsetInChars = CharUnits::Zero(); for (unsigned i = 0, e = Elements.size(); i != e; ++i) { llvm::Constant *C = Elements[i]; CharUnits ElementAlign = CharUnits::fromQuantity( CGM.getDataLayout().getABITypeAlignment(C->getType())); CharUnits AlignedElementOffsetInChars = ElementOffsetInChars.RoundUpToAlignment(ElementAlign); if (AlignedElementOffsetInChars > ElementOffsetInChars) { // We need some padding. CharUnits NumChars = AlignedElementOffsetInChars - ElementOffsetInChars; llvm::Type *Ty = CGM.Int8Ty; if (NumChars > CharUnits::One()) Ty = llvm::ArrayType::get(Ty, NumChars.getQuantity()); llvm::Constant *Padding = llvm::UndefValue::get(Ty); PackedElements.push_back(Padding); ElementOffsetInChars += getSizeInChars(Padding); } PackedElements.push_back(C); ElementOffsetInChars += getSizeInChars(C); } assert(ElementOffsetInChars == NextFieldOffsetInChars && "Packing the struct changed its size!"); Elements.swap(PackedElements); LLVMStructAlignment = CharUnits::One(); Packed = true; } bool ConstStructBuilder::Build(InitListExpr *ILE) { RecordDecl *RD = ILE->getType()->getAs()->getDecl(); const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); unsigned FieldNo = 0; unsigned ElementNo = 0; for (RecordDecl::field_iterator Field = RD->field_begin(), FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) { // If this is a union, skip all the fields that aren't being initialized. if (RD->isUnion() && ILE->getInitializedFieldInUnion() != *Field) continue; // Don't emit anonymous bitfields, they just affect layout. if (Field->isUnnamedBitfield()) continue; // Get the initializer. A struct can include fields without initializers, // we just use explicit null values for them. llvm::Constant *EltInit; if (ElementNo < ILE->getNumInits()) EltInit = CGM.EmitConstantExpr(ILE->getInit(ElementNo++), Field->getType(), CGF); else EltInit = CGM.EmitNullConstant(Field->getType()); if (!EltInit) return false; if (!Field->isBitField()) { // Handle non-bitfield members. AppendField(*Field, Layout.getFieldOffset(FieldNo), EltInit); } else { // Otherwise we have a bitfield. AppendBitField(*Field, Layout.getFieldOffset(FieldNo), cast(EltInit)); } } return true; } namespace { struct BaseInfo { BaseInfo(const CXXRecordDecl *Decl, CharUnits Offset, unsigned Index) : Decl(Decl), Offset(Offset), Index(Index) { } const CXXRecordDecl *Decl; CharUnits Offset; unsigned Index; bool operator<(const BaseInfo &O) const { return Offset < O.Offset; } }; } void ConstStructBuilder::Build(const APValue &Val, const RecordDecl *RD, bool IsPrimaryBase, const CXXRecordDecl *VTableClass, CharUnits Offset) { const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); if (const CXXRecordDecl *CD = dyn_cast(RD)) { // Add a vtable pointer, if we need one and it hasn't already been added. if (CD->isDynamicClass() && !IsPrimaryBase) { llvm::Constant *VTableAddressPoint = CGM.getCXXABI().getVTableAddressPointForConstExpr( BaseSubobject(CD, Offset), VTableClass); AppendBytes(Offset, VTableAddressPoint); } // Accumulate and sort bases, in order to visit them in address order, which // may not be the same as declaration order. SmallVector Bases; Bases.reserve(CD->getNumBases()); unsigned BaseNo = 0; for (CXXRecordDecl::base_class_const_iterator Base = CD->bases_begin(), BaseEnd = CD->bases_end(); Base != BaseEnd; ++Base, ++BaseNo) { assert(!Base->isVirtual() && "should not have virtual bases here"); const CXXRecordDecl *BD = Base->getType()->getAsCXXRecordDecl(); CharUnits BaseOffset = Layout.getBaseClassOffset(BD); Bases.push_back(BaseInfo(BD, BaseOffset, BaseNo)); } std::stable_sort(Bases.begin(), Bases.end()); for (unsigned I = 0, N = Bases.size(); I != N; ++I) { BaseInfo &Base = Bases[I]; bool IsPrimaryBase = Layout.getPrimaryBase() == Base.Decl; Build(Val.getStructBase(Base.Index), Base.Decl, IsPrimaryBase, VTableClass, Offset + Base.Offset); } } unsigned FieldNo = 0; uint64_t OffsetBits = CGM.getContext().toBits(Offset); for (RecordDecl::field_iterator Field = RD->field_begin(), FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) { // If this is a union, skip all the fields that aren't being initialized. if (RD->isUnion() && Val.getUnionField() != *Field) continue; // Don't emit anonymous bitfields, they just affect layout. if (Field->isUnnamedBitfield()) continue; // Emit the value of the initializer. const APValue &FieldValue = RD->isUnion() ? Val.getUnionValue() : Val.getStructField(FieldNo); llvm::Constant *EltInit = CGM.EmitConstantValueForMemory(FieldValue, Field->getType(), CGF); assert(EltInit && "EmitConstantValue can't fail"); if (!Field->isBitField()) { // Handle non-bitfield members. AppendField(*Field, Layout.getFieldOffset(FieldNo) + OffsetBits, EltInit); } else { // Otherwise we have a bitfield. AppendBitField(*Field, Layout.getFieldOffset(FieldNo) + OffsetBits, cast(EltInit)); } } } llvm::Constant *ConstStructBuilder::Finalize(QualType Ty) { RecordDecl *RD = Ty->getAs()->getDecl(); const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); CharUnits LayoutSizeInChars = Layout.getSize(); if (NextFieldOffsetInChars > LayoutSizeInChars) { // If the struct is bigger than the size of the record type, // we must have a flexible array member at the end. assert(RD->hasFlexibleArrayMember() && "Must have flexible array member if struct is bigger than type!"); // No tail padding is necessary. } else { // Append tail padding if necessary. AppendTailPadding(LayoutSizeInChars); CharUnits LLVMSizeInChars = NextFieldOffsetInChars.RoundUpToAlignment(LLVMStructAlignment); // Check if we need to convert the struct to a packed struct. if (NextFieldOffsetInChars <= LayoutSizeInChars && LLVMSizeInChars > LayoutSizeInChars) { assert(!Packed && "Size mismatch!"); ConvertStructToPacked(); assert(NextFieldOffsetInChars <= LayoutSizeInChars && "Converting to packed did not help!"); } assert(LayoutSizeInChars == NextFieldOffsetInChars && "Tail padding mismatch!"); } // Pick the type to use. If the type is layout identical to the ConvertType // type then use it, otherwise use whatever the builder produced for us. llvm::StructType *STy = llvm::ConstantStruct::getTypeForElements(CGM.getLLVMContext(), Elements, Packed); llvm::Type *ValTy = CGM.getTypes().ConvertType(Ty); if (llvm::StructType *ValSTy = dyn_cast(ValTy)) { if (ValSTy->isLayoutIdentical(STy)) STy = ValSTy; } llvm::Constant *Result = llvm::ConstantStruct::get(STy, Elements); assert(NextFieldOffsetInChars.RoundUpToAlignment(getAlignment(Result)) == getSizeInChars(Result) && "Size mismatch!"); return Result; } llvm::Constant *ConstStructBuilder::BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, InitListExpr *ILE) { ConstStructBuilder Builder(CGM, CGF); if (!Builder.Build(ILE)) return 0; return Builder.Finalize(ILE->getType()); } llvm::Constant *ConstStructBuilder::BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, const APValue &Val, QualType ValTy) { ConstStructBuilder Builder(CGM, CGF); const RecordDecl *RD = ValTy->castAs()->getDecl(); const CXXRecordDecl *CD = dyn_cast(RD); Builder.Build(Val, RD, false, CD, CharUnits::Zero()); return Builder.Finalize(ValTy); } //===----------------------------------------------------------------------===// // ConstExprEmitter //===----------------------------------------------------------------------===// /// This class only needs to handle two cases: /// 1) Literals (this is used by APValue emission to emit literals). /// 2) Arrays, structs and unions (outside C++11 mode, we don't currently /// constant fold these types). class ConstExprEmitter : public StmtVisitor { CodeGenModule &CGM; CodeGenFunction *CGF; llvm::LLVMContext &VMContext; public: ConstExprEmitter(CodeGenModule &cgm, CodeGenFunction *cgf) : CGM(cgm), CGF(cgf), VMContext(cgm.getLLVMContext()) { } //===--------------------------------------------------------------------===// // Visitor Methods //===--------------------------------------------------------------------===// llvm::Constant *VisitStmt(Stmt *S) { return 0; } llvm::Constant *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } llvm::Constant * VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE) { return Visit(PE->getReplacement()); } llvm::Constant *VisitGenericSelectionExpr(GenericSelectionExpr *GE) { return Visit(GE->getResultExpr()); } llvm::Constant *VisitChooseExpr(ChooseExpr *CE) { return Visit(CE->getChosenSubExpr()); } llvm::Constant *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { return Visit(E->getInitializer()); } llvm::Constant *VisitCastExpr(CastExpr* E) { Expr *subExpr = E->getSubExpr(); llvm::Constant *C = CGM.EmitConstantExpr(subExpr, subExpr->getType(), CGF); if (!C) return 0; llvm::Type *destType = ConvertType(E->getType()); switch (E->getCastKind()) { case CK_ToUnion: { // GCC cast to union extension assert(E->getType()->isUnionType() && "Destination type is not union type!"); // Build a struct with the union sub-element as the first member, // and padded to the appropriate size SmallVector Elts; SmallVector Types; Elts.push_back(C); Types.push_back(C->getType()); unsigned CurSize = CGM.getDataLayout().getTypeAllocSize(C->getType()); unsigned TotalSize = CGM.getDataLayout().getTypeAllocSize(destType); assert(CurSize <= TotalSize && "Union size mismatch!"); if (unsigned NumPadBytes = TotalSize - CurSize) { llvm::Type *Ty = CGM.Int8Ty; if (NumPadBytes > 1) Ty = llvm::ArrayType::get(Ty, NumPadBytes); Elts.push_back(llvm::UndefValue::get(Ty)); Types.push_back(Ty); } llvm::StructType* STy = llvm::StructType::get(C->getType()->getContext(), Types, false); return llvm::ConstantStruct::get(STy, Elts); } case CK_LValueToRValue: case CK_AtomicToNonAtomic: case CK_NonAtomicToAtomic: case CK_NoOp: case CK_ConstructorConversion: return C; case CK_Dependent: llvm_unreachable("saw dependent cast!"); case CK_BuiltinFnToFnPtr: llvm_unreachable("builtin functions are handled elsewhere"); case CK_ReinterpretMemberPointer: case CK_DerivedToBaseMemberPointer: case CK_BaseToDerivedMemberPointer: return CGM.getCXXABI().EmitMemberPointerConversion(E, C); // These will never be supported. case CK_ObjCObjectLValueCast: case CK_ARCProduceObject: case CK_ARCConsumeObject: case CK_ARCReclaimReturnedObject: case CK_ARCExtendBlockObject: case CK_CopyAndAutoreleaseBlockObject: return 0; // These don't need to be handled here because Evaluate knows how to // evaluate them in the cases where they can be folded. case CK_BitCast: case CK_ToVoid: case CK_Dynamic: case CK_LValueBitCast: case CK_NullToMemberPointer: case CK_UserDefinedConversion: case CK_CPointerToObjCPointerCast: case CK_BlockPointerToObjCPointerCast: case CK_AnyPointerToBlockPointerCast: case CK_ArrayToPointerDecay: case CK_FunctionToPointerDecay: case CK_BaseToDerived: case CK_DerivedToBase: case CK_UncheckedDerivedToBase: case CK_MemberPointerToBoolean: case CK_VectorSplat: case CK_FloatingRealToComplex: case CK_FloatingComplexToReal: case CK_FloatingComplexToBoolean: case CK_FloatingComplexCast: case CK_FloatingComplexToIntegralComplex: case CK_IntegralRealToComplex: case CK_IntegralComplexToReal: case CK_IntegralComplexToBoolean: case CK_IntegralComplexCast: case CK_IntegralComplexToFloatingComplex: case CK_PointerToIntegral: case CK_PointerToBoolean: case CK_NullToPointer: case CK_IntegralCast: case CK_IntegralToPointer: case CK_IntegralToBoolean: case CK_IntegralToFloating: case CK_FloatingToIntegral: case CK_FloatingToBoolean: case CK_FloatingCast: case CK_ZeroToOCLEvent: return 0; } llvm_unreachable("Invalid CastKind"); } llvm::Constant *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { return Visit(DAE->getExpr()); } llvm::Constant *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) { // No need for a DefaultInitExprScope: we don't handle 'this' in a // constant expression. return Visit(DIE->getExpr()); } llvm::Constant *VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E) { return Visit(E->GetTemporaryExpr()); } llvm::Constant *EmitArrayInitialization(InitListExpr *ILE) { if (ILE->isStringLiteralInit()) return Visit(ILE->getInit(0)); llvm::ArrayType *AType = cast(ConvertType(ILE->getType())); llvm::Type *ElemTy = AType->getElementType(); unsigned NumInitElements = ILE->getNumInits(); unsigned NumElements = AType->getNumElements(); // Initialising an array requires us to automatically // initialise any elements that have not been initialised explicitly unsigned NumInitableElts = std::min(NumInitElements, NumElements); // Copy initializer elements. std::vector Elts; Elts.reserve(NumInitableElts + NumElements); bool RewriteType = false; for (unsigned i = 0; i < NumInitableElts; ++i) { Expr *Init = ILE->getInit(i); llvm::Constant *C = CGM.EmitConstantExpr(Init, Init->getType(), CGF); if (!C) return 0; RewriteType |= (C->getType() != ElemTy); Elts.push_back(C); } // Initialize remaining array elements. // FIXME: This doesn't handle member pointers correctly! llvm::Constant *fillC; if (Expr *filler = ILE->getArrayFiller()) fillC = CGM.EmitConstantExpr(filler, filler->getType(), CGF); else fillC = llvm::Constant::getNullValue(ElemTy); if (!fillC) return 0; RewriteType |= (fillC->getType() != ElemTy); Elts.resize(NumElements, fillC); if (RewriteType) { // FIXME: Try to avoid packing the array std::vector Types; Types.reserve(NumInitableElts + NumElements); for (unsigned i = 0, e = Elts.size(); i < e; ++i) Types.push_back(Elts[i]->getType()); llvm::StructType *SType = llvm::StructType::get(AType->getContext(), Types, true); return llvm::ConstantStruct::get(SType, Elts); } return llvm::ConstantArray::get(AType, Elts); } llvm::Constant *EmitRecordInitialization(InitListExpr *ILE) { return ConstStructBuilder::BuildStruct(CGM, CGF, ILE); } llvm::Constant *VisitImplicitValueInitExpr(ImplicitValueInitExpr* E) { return CGM.EmitNullConstant(E->getType()); } llvm::Constant *VisitInitListExpr(InitListExpr *ILE) { if (ILE->getType()->isArrayType()) return EmitArrayInitialization(ILE); if (ILE->getType()->isRecordType()) return EmitRecordInitialization(ILE); return 0; } llvm::Constant *VisitCXXConstructExpr(CXXConstructExpr *E) { if (!E->getConstructor()->isTrivial()) return 0; QualType Ty = E->getType(); // FIXME: We should not have to call getBaseElementType here. const RecordType *RT = CGM.getContext().getBaseElementType(Ty)->getAs(); const CXXRecordDecl *RD = cast(RT->getDecl()); // If the class doesn't have a trivial destructor, we can't emit it as a // constant expr. if (!RD->hasTrivialDestructor()) return 0; // Only copy and default constructors can be trivial. if (E->getNumArgs()) { assert(E->getNumArgs() == 1 && "trivial ctor with > 1 argument"); assert(E->getConstructor()->isCopyOrMoveConstructor() && "trivial ctor has argument but isn't a copy/move ctor"); Expr *Arg = E->getArg(0); assert(CGM.getContext().hasSameUnqualifiedType(Ty, Arg->getType()) && "argument to copy ctor is of wrong type"); return Visit(Arg); } return CGM.EmitNullConstant(Ty); } llvm::Constant *VisitStringLiteral(StringLiteral *E) { return CGM.GetConstantArrayFromStringLiteral(E); } llvm::Constant *VisitObjCEncodeExpr(ObjCEncodeExpr *E) { // This must be an @@encode initializing an array in a static initializer. // Don't emit it as the address of the string, emit the string data itself // as an inline array. std::string Str; CGM.getContext().getObjCEncodingForType(E->getEncodedType(), Str); const ConstantArrayType *CAT = cast(E->getType()); // Resize the string to the right size, adding zeros at the end, or // truncating as needed. Str.resize(CAT->getSize().getZExtValue(), '\0'); return llvm::ConstantDataArray::getString(VMContext, Str, false); } llvm::Constant *VisitUnaryExtension(const UnaryOperator *E) { return Visit(E->getSubExpr()); } // Utility methods llvm::Type *ConvertType(QualType T) { return CGM.getTypes().ConvertType(T); } public: llvm::Constant *EmitLValue(APValue::LValueBase LVBase) { if (const ValueDecl *Decl = LVBase.dyn_cast()) { if (Decl->hasAttr()) return CGM.GetWeakRefReference(Decl); if (const FunctionDecl *FD = dyn_cast(Decl)) return CGM.GetAddrOfFunction(FD); if (const VarDecl* VD = dyn_cast(Decl)) { // We can never refer to a variable with local storage. if (!VD->hasLocalStorage()) { if (VD->isFileVarDecl() || VD->hasExternalStorage()) return CGM.GetAddrOfGlobalVar(VD); else if (VD->isLocalVarDecl()) return CGM.getStaticLocalDeclAddress(VD); } } return 0; } Expr *E = const_cast(LVBase.get()); switch (E->getStmtClass()) { default: break; case Expr::CompoundLiteralExprClass: { // Note that due to the nature of compound literals, this is guaranteed // to be the only use of the variable, so we just generate it here. CompoundLiteralExpr *CLE = cast(E); llvm::Constant* C = CGM.EmitConstantExpr(CLE->getInitializer(), CLE->getType(), CGF); // FIXME: "Leaked" on failure. if (C) C = new llvm::GlobalVariable(CGM.getModule(), C->getType(), E->getType().isConstant(CGM.getContext()), llvm::GlobalValue::InternalLinkage, C, ".compoundliteral", 0, llvm::GlobalVariable::NotThreadLocal, CGM.getContext().getTargetAddressSpace(E->getType())); return C; } case Expr::StringLiteralClass: return CGM.GetAddrOfConstantStringFromLiteral(cast(E)); case Expr::ObjCEncodeExprClass: return CGM.GetAddrOfConstantStringFromObjCEncode(cast(E)); case Expr::ObjCStringLiteralClass: { ObjCStringLiteral* SL = cast(E); llvm::Constant *C = CGM.getObjCRuntime().GenerateConstantString(SL->getString()); return llvm::ConstantExpr::getBitCast(C, ConvertType(E->getType())); } case Expr::PredefinedExprClass: { unsigned Type = cast(E)->getIdentType(); if (CGF) { LValue Res = CGF->EmitPredefinedLValue(cast(E)); return cast(Res.getAddress()); } else if (Type == PredefinedExpr::PrettyFunction) { return CGM.GetAddrOfConstantCString("top level", ".tmp"); } return CGM.GetAddrOfConstantCString("", ".tmp"); } case Expr::AddrLabelExprClass: { assert(CGF && "Invalid address of label expression outside function."); llvm::Constant *Ptr = CGF->GetAddrOfLabel(cast(E)->getLabel()); return llvm::ConstantExpr::getBitCast(Ptr, ConvertType(E->getType())); } case Expr::CallExprClass: { CallExpr* CE = cast(E); unsigned builtin = CE->isBuiltinCall(); if (builtin != Builtin::BI__builtin___CFStringMakeConstantString && builtin != Builtin::BI__builtin___NSStringMakeConstantString) break; const Expr *Arg = CE->getArg(0)->IgnoreParenCasts(); const StringLiteral *Literal = cast(Arg); if (builtin == Builtin::BI__builtin___NSStringMakeConstantString) { return CGM.getObjCRuntime().GenerateConstantString(Literal); } // FIXME: need to deal with UCN conversion issues. return CGM.GetAddrOfConstantCFString(Literal); } case Expr::BlockExprClass: { std::string FunctionName; if (CGF) FunctionName = CGF->CurFn->getName(); else FunctionName = "global"; return CGM.GetAddrOfGlobalBlock(cast(E), FunctionName.c_str()); } case Expr::CXXTypeidExprClass: { CXXTypeidExpr *Typeid = cast(E); QualType T; if (Typeid->isTypeOperand()) T = Typeid->getTypeOperand(CGM.getContext()); else T = Typeid->getExprOperand()->getType(); return CGM.GetAddrOfRTTIDescriptor(T); } case Expr::CXXUuidofExprClass: { return CGM.GetAddrOfUuidDescriptor(cast(E)); } case Expr::MaterializeTemporaryExprClass: { MaterializeTemporaryExpr *MTE = cast(E); assert(MTE->getStorageDuration() == SD_Static); SmallVector CommaLHSs; SmallVector Adjustments; const Expr *Inner = MTE->GetTemporaryExpr() ->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); return CGM.GetAddrOfGlobalTemporary(MTE, Inner); } } return 0; } }; } // end anonymous namespace. llvm::Constant *CodeGenModule::EmitConstantInit(const VarDecl &D, CodeGenFunction *CGF) { // Make a quick check if variable can be default NULL initialized // and avoid going through rest of code which may do, for c++11, // initialization of memory to all NULLs. if (!D.hasLocalStorage()) { QualType Ty = D.getType(); if (Ty->isArrayType()) Ty = Context.getBaseElementType(Ty); if (Ty->isRecordType()) if (const CXXConstructExpr *E = dyn_cast_or_null(D.getInit())) { const CXXConstructorDecl *CD = E->getConstructor(); if (CD->isTrivial() && CD->isDefaultConstructor()) return EmitNullConstant(D.getType()); } } if (const APValue *Value = D.evaluateValue()) return EmitConstantValueForMemory(*Value, D.getType(), CGF); // FIXME: Implement C++11 [basic.start.init]p2: if the initializer of a // reference is a constant expression, and the reference binds to a temporary, // then constant initialization is performed. ConstExprEmitter will // incorrectly emit a prvalue constant in this case, and the calling code // interprets that as the (pointer) value of the reference, rather than the // desired value of the referee. if (D.getType()->isReferenceType()) return 0; const Expr *E = D.getInit(); assert(E && "No initializer to emit"); llvm::Constant* C = ConstExprEmitter(*this, CGF).Visit(const_cast(E)); if (C && C->getType()->isIntegerTy(1)) { llvm::Type *BoolTy = getTypes().ConvertTypeForMem(E->getType()); C = llvm::ConstantExpr::getZExt(C, BoolTy); } return C; } llvm::Constant *CodeGenModule::EmitConstantExpr(const Expr *E, QualType DestType, CodeGenFunction *CGF) { Expr::EvalResult Result; bool Success = false; if (DestType->isReferenceType()) Success = E->EvaluateAsLValue(Result, Context); else Success = E->EvaluateAsRValue(Result, Context); llvm::Constant *C = 0; if (Success && !Result.HasSideEffects) C = EmitConstantValue(Result.Val, DestType, CGF); else C = ConstExprEmitter(*this, CGF).Visit(const_cast(E)); if (C && C->getType()->isIntegerTy(1)) { llvm::Type *BoolTy = getTypes().ConvertTypeForMem(E->getType()); C = llvm::ConstantExpr::getZExt(C, BoolTy); } return C; } llvm::Constant *CodeGenModule::EmitConstantValue(const APValue &Value, QualType DestType, CodeGenFunction *CGF) { switch (Value.getKind()) { case APValue::Uninitialized: llvm_unreachable("Constant expressions should be initialized."); case APValue::LValue: { llvm::Type *DestTy = getTypes().ConvertTypeForMem(DestType); llvm::Constant *Offset = llvm::ConstantInt::get(Int64Ty, Value.getLValueOffset().getQuantity()); llvm::Constant *C; if (APValue::LValueBase LVBase = Value.getLValueBase()) { // An array can be represented as an lvalue referring to the base. if (isa(DestTy)) { assert(Offset->isNullValue() && "offset on array initializer"); return ConstExprEmitter(*this, CGF).Visit( const_cast(LVBase.get())); } C = ConstExprEmitter(*this, CGF).EmitLValue(LVBase); // Apply offset if necessary. if (!Offset->isNullValue()) { llvm::Constant *Casted = llvm::ConstantExpr::getBitCast(C, Int8PtrTy); Casted = llvm::ConstantExpr::getGetElementPtr(Casted, Offset); C = llvm::ConstantExpr::getBitCast(Casted, C->getType()); } // Convert to the appropriate type; this could be an lvalue for // an integer. if (isa(DestTy)) return llvm::ConstantExpr::getBitCast(C, DestTy); return llvm::ConstantExpr::getPtrToInt(C, DestTy); } else { C = Offset; // Convert to the appropriate type; this could be an lvalue for // an integer. if (isa(DestTy)) return llvm::ConstantExpr::getIntToPtr(C, DestTy); // If the types don't match this should only be a truncate. if (C->getType() != DestTy) return llvm::ConstantExpr::getTrunc(C, DestTy); return C; } } case APValue::Int: return llvm::ConstantInt::get(VMContext, Value.getInt()); case APValue::ComplexInt: { llvm::Constant *Complex[2]; Complex[0] = llvm::ConstantInt::get(VMContext, Value.getComplexIntReal()); Complex[1] = llvm::ConstantInt::get(VMContext, Value.getComplexIntImag()); // FIXME: the target may want to specify that this is packed. llvm::StructType *STy = llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType(), NULL); return llvm::ConstantStruct::get(STy, Complex); } case APValue::Float: { const llvm::APFloat &Init = Value.getFloat(); if (&Init.getSemantics() == &llvm::APFloat::IEEEhalf && !Context.getLangOpts().NativeHalfType) return llvm::ConstantInt::get(VMContext, Init.bitcastToAPInt()); else return llvm::ConstantFP::get(VMContext, Init); } case APValue::ComplexFloat: { llvm::Constant *Complex[2]; Complex[0] = llvm::ConstantFP::get(VMContext, Value.getComplexFloatReal()); Complex[1] = llvm::ConstantFP::get(VMContext, Value.getComplexFloatImag()); // FIXME: the target may want to specify that this is packed. llvm::StructType *STy = llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType(), NULL); return llvm::ConstantStruct::get(STy, Complex); } case APValue::Vector: { SmallVector Inits; unsigned NumElts = Value.getVectorLength(); for (unsigned i = 0; i != NumElts; ++i) { const APValue &Elt = Value.getVectorElt(i); if (Elt.isInt()) Inits.push_back(llvm::ConstantInt::get(VMContext, Elt.getInt())); else Inits.push_back(llvm::ConstantFP::get(VMContext, Elt.getFloat())); } return llvm::ConstantVector::get(Inits); } case APValue::AddrLabelDiff: { const AddrLabelExpr *LHSExpr = Value.getAddrLabelDiffLHS(); const AddrLabelExpr *RHSExpr = Value.getAddrLabelDiffRHS(); llvm::Constant *LHS = EmitConstantExpr(LHSExpr, LHSExpr->getType(), CGF); llvm::Constant *RHS = EmitConstantExpr(RHSExpr, RHSExpr->getType(), CGF); // Compute difference llvm::Type *ResultType = getTypes().ConvertType(DestType); LHS = llvm::ConstantExpr::getPtrToInt(LHS, IntPtrTy); RHS = llvm::ConstantExpr::getPtrToInt(RHS, IntPtrTy); llvm::Constant *AddrLabelDiff = llvm::ConstantExpr::getSub(LHS, RHS); // LLVM is a bit sensitive about the exact format of the // address-of-label difference; make sure to truncate after // the subtraction. return llvm::ConstantExpr::getTruncOrBitCast(AddrLabelDiff, ResultType); } case APValue::Struct: case APValue::Union: return ConstStructBuilder::BuildStruct(*this, CGF, Value, DestType); case APValue::Array: { const ArrayType *CAT = Context.getAsArrayType(DestType); unsigned NumElements = Value.getArraySize(); unsigned NumInitElts = Value.getArrayInitializedElts(); std::vector Elts; Elts.reserve(NumElements); // Emit array filler, if there is one. llvm::Constant *Filler = 0; if (Value.hasArrayFiller()) Filler = EmitConstantValueForMemory(Value.getArrayFiller(), CAT->getElementType(), CGF); // Emit initializer elements. llvm::Type *CommonElementType = 0; for (unsigned I = 0; I < NumElements; ++I) { llvm::Constant *C = Filler; if (I < NumInitElts) C = EmitConstantValueForMemory(Value.getArrayInitializedElt(I), CAT->getElementType(), CGF); else assert(Filler && "Missing filler for implicit elements of initializer"); if (I == 0) CommonElementType = C->getType(); else if (C->getType() != CommonElementType) CommonElementType = 0; Elts.push_back(C); } if (!CommonElementType) { // FIXME: Try to avoid packing the array std::vector Types; Types.reserve(NumElements); for (unsigned i = 0, e = Elts.size(); i < e; ++i) Types.push_back(Elts[i]->getType()); llvm::StructType *SType = llvm::StructType::get(VMContext, Types, true); return llvm::ConstantStruct::get(SType, Elts); } llvm::ArrayType *AType = llvm::ArrayType::get(CommonElementType, NumElements); return llvm::ConstantArray::get(AType, Elts); } case APValue::MemberPointer: return getCXXABI().EmitMemberPointer(Value, DestType); } llvm_unreachable("Unknown APValue kind"); } llvm::Constant * CodeGenModule::EmitConstantValueForMemory(const APValue &Value, QualType DestType, CodeGenFunction *CGF) { llvm::Constant *C = EmitConstantValue(Value, DestType, CGF); if (C->getType()->isIntegerTy(1)) { llvm::Type *BoolTy = getTypes().ConvertTypeForMem(DestType); C = llvm::ConstantExpr::getZExt(C, BoolTy); } return C; } llvm::Constant * CodeGenModule::GetAddrOfConstantCompoundLiteral(const CompoundLiteralExpr *E) { assert(E->isFileScope() && "not a file-scope compound literal expr"); return ConstExprEmitter(*this, 0).EmitLValue(E); } llvm::Constant * CodeGenModule::getMemberPointerConstant(const UnaryOperator *uo) { // Member pointer constants always have a very particular form. const MemberPointerType *type = cast(uo->getType()); const ValueDecl *decl = cast(uo->getSubExpr())->getDecl(); // A member function pointer. if (const CXXMethodDecl *method = dyn_cast(decl)) return getCXXABI().EmitMemberPointer(method); // Otherwise, a member data pointer. uint64_t fieldOffset = getContext().getFieldOffset(decl); CharUnits chars = getContext().toCharUnitsFromBits((int64_t) fieldOffset); return getCXXABI().EmitMemberDataPointer(type, chars); } static void FillInNullDataMemberPointers(CodeGenModule &CGM, QualType T, SmallVectorImpl &Elements, uint64_t StartOffset) { assert(StartOffset % CGM.getContext().getCharWidth() == 0 && "StartOffset not byte aligned!"); if (CGM.getTypes().isZeroInitializable(T)) return; if (const ConstantArrayType *CAT = CGM.getContext().getAsConstantArrayType(T)) { QualType ElementTy = CAT->getElementType(); uint64_t ElementSize = CGM.getContext().getTypeSize(ElementTy); for (uint64_t I = 0, E = CAT->getSize().getZExtValue(); I != E; ++I) { FillInNullDataMemberPointers(CGM, ElementTy, Elements, StartOffset + I * ElementSize); } } else if (const RecordType *RT = T->getAs()) { const CXXRecordDecl *RD = cast(RT->getDecl()); const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); // Go through all bases and fill in any null pointer to data members. for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(), E = RD->bases_end(); I != E; ++I) { if (I->isVirtual()) { // Ignore virtual bases. continue; } const CXXRecordDecl *BaseDecl = cast(I->getType()->getAs()->getDecl()); // Ignore empty bases. if (BaseDecl->isEmpty()) continue; // Ignore bases that don't have any pointer to data members. if (CGM.getTypes().isZeroInitializable(BaseDecl)) continue; uint64_t BaseOffset = CGM.getContext().toBits(Layout.getBaseClassOffset(BaseDecl)); FillInNullDataMemberPointers(CGM, I->getType(), Elements, StartOffset + BaseOffset); } // Visit all fields. unsigned FieldNo = 0; for (RecordDecl::field_iterator I = RD->field_begin(), E = RD->field_end(); I != E; ++I, ++FieldNo) { QualType FieldType = I->getType(); if (CGM.getTypes().isZeroInitializable(FieldType)) continue; uint64_t FieldOffset = StartOffset + Layout.getFieldOffset(FieldNo); FillInNullDataMemberPointers(CGM, FieldType, Elements, FieldOffset); } } else { assert(T->isMemberPointerType() && "Should only see member pointers here!"); assert(!T->getAs()->getPointeeType()->isFunctionType() && "Should only see pointers to data members here!"); CharUnits StartIndex = CGM.getContext().toCharUnitsFromBits(StartOffset); CharUnits EndIndex = StartIndex + CGM.getContext().getTypeSizeInChars(T); // FIXME: hardcodes Itanium member pointer representation! llvm::Constant *NegativeOne = llvm::ConstantInt::get(CGM.Int8Ty, -1ULL, /*isSigned*/true); // Fill in the null data member pointer. for (CharUnits I = StartIndex; I != EndIndex; ++I) Elements[I.getQuantity()] = NegativeOne; } } static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM, llvm::Type *baseType, const CXXRecordDecl *base); static llvm::Constant *EmitNullConstant(CodeGenModule &CGM, const CXXRecordDecl *record, bool asCompleteObject) { const CGRecordLayout &layout = CGM.getTypes().getCGRecordLayout(record); llvm::StructType *structure = (asCompleteObject ? layout.getLLVMType() : layout.getBaseSubobjectLLVMType()); unsigned numElements = structure->getNumElements(); std::vector elements(numElements); // Fill in all the bases. for (CXXRecordDecl::base_class_const_iterator I = record->bases_begin(), E = record->bases_end(); I != E; ++I) { if (I->isVirtual()) { // Ignore virtual bases; if we're laying out for a complete // object, we'll lay these out later. continue; } const CXXRecordDecl *base = cast(I->getType()->castAs()->getDecl()); // Ignore empty bases. if (base->isEmpty()) continue; unsigned fieldIndex = layout.getNonVirtualBaseLLVMFieldNo(base); llvm::Type *baseType = structure->getElementType(fieldIndex); elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base); } // Fill in all the fields. for (RecordDecl::field_iterator I = record->field_begin(), E = record->field_end(); I != E; ++I) { const FieldDecl *field = *I; // Fill in non-bitfields. (Bitfields always use a zero pattern, which we // will fill in later.) if (!field->isBitField()) { unsigned fieldIndex = layout.getLLVMFieldNo(field); elements[fieldIndex] = CGM.EmitNullConstant(field->getType()); } // For unions, stop after the first named field. if (record->isUnion() && field->getDeclName()) break; } // Fill in the virtual bases, if we're working with the complete object. if (asCompleteObject) { for (CXXRecordDecl::base_class_const_iterator I = record->vbases_begin(), E = record->vbases_end(); I != E; ++I) { const CXXRecordDecl *base = cast(I->getType()->castAs()->getDecl()); // Ignore empty bases. if (base->isEmpty()) continue; unsigned fieldIndex = layout.getVirtualBaseIndex(base); // We might have already laid this field out. if (elements[fieldIndex]) continue; llvm::Type *baseType = structure->getElementType(fieldIndex); elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base); } } // Now go through all other fields and zero them out. for (unsigned i = 0; i != numElements; ++i) { if (!elements[i]) elements[i] = llvm::Constant::getNullValue(structure->getElementType(i)); } return llvm::ConstantStruct::get(structure, elements); } /// Emit the null constant for a base subobject. static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM, llvm::Type *baseType, const CXXRecordDecl *base) { const CGRecordLayout &baseLayout = CGM.getTypes().getCGRecordLayout(base); // Just zero out bases that don't have any pointer to data members. if (baseLayout.isZeroInitializableAsBase()) return llvm::Constant::getNullValue(baseType); // If the base type is a struct, we can just use its null constant. if (isa(baseType)) { return EmitNullConstant(CGM, base, /*complete*/ false); } // Otherwise, some bases are represented as arrays of i8 if the size // of the base is smaller than its corresponding LLVM type. Figure // out how many elements this base array has. llvm::ArrayType *baseArrayType = cast(baseType); unsigned numBaseElements = baseArrayType->getNumElements(); // Fill in null data member pointers. SmallVector baseElements(numBaseElements); FillInNullDataMemberPointers(CGM, CGM.getContext().getTypeDeclType(base), baseElements, 0); // Now go through all other elements and zero them out. if (numBaseElements) { llvm::Constant *i8_zero = llvm::Constant::getNullValue(CGM.Int8Ty); for (unsigned i = 0; i != numBaseElements; ++i) { if (!baseElements[i]) baseElements[i] = i8_zero; } } return llvm::ConstantArray::get(baseArrayType, baseElements); } llvm::Constant *CodeGenModule::EmitNullConstant(QualType T) { if (getTypes().isZeroInitializable(T)) return llvm::Constant::getNullValue(getTypes().ConvertTypeForMem(T)); if (const ConstantArrayType *CAT = Context.getAsConstantArrayType(T)) { llvm::ArrayType *ATy = cast(getTypes().ConvertTypeForMem(T)); QualType ElementTy = CAT->getElementType(); llvm::Constant *Element = EmitNullConstant(ElementTy); unsigned NumElements = CAT->getSize().getZExtValue(); if (Element->isNullValue()) return llvm::ConstantAggregateZero::get(ATy); SmallVector Array(NumElements, Element); return llvm::ConstantArray::get(ATy, Array); } if (const RecordType *RT = T->getAs()) { const CXXRecordDecl *RD = cast(RT->getDecl()); return ::EmitNullConstant(*this, RD, /*complete object*/ true); } assert(T->isMemberPointerType() && "Should only see member pointers here!"); assert(!T->getAs()->getPointeeType()->isFunctionType() && "Should only see pointers to data members here!"); // Itanium C++ ABI 2.3: // A NULL pointer is represented as -1. return getCXXABI().EmitNullMemberPointer(T->castAs()); } llvm::Constant * CodeGenModule::EmitNullConstantForBase(const CXXRecordDecl *Record) { return ::EmitNullConstant(*this, Record, false); } @ 1.1.1.1 log @Import Clang 3.4rc1 r195771. @ text @@ 1.1.1.2 log @Import clang 3.5svn r198450. @ text @a635 3 case CK_AddressSpaceConversion: return llvm::ConstantExpr::getAddrSpaceCast(C, destType); d920 1 a920 1 unsigned builtin = CE->getBuiltinCallee(); d1065 1 a1065 1 C = llvm::ConstantExpr::getPointerCast(Casted, C->getType()); d1071 1 a1071 1 return llvm::ConstantExpr::getPointerCast(C, DestTy); @ 1.1.1.2.2.1 log @Rebase. @ text @d533 1 a533 1 return nullptr; d575 1 a575 1 return nullptr; d602 1 a602 1 if (!C) return nullptr; d663 1 a663 1 return nullptr; d704 1 a704 1 return nullptr; d746 1 a746 1 return nullptr; d759 1 a759 1 return nullptr; d792 1 a792 1 return nullptr; d797 1 a797 1 return nullptr; d809 2 a810 2 return nullptr; d839 1 a839 4 QualType T = E->getType(); if (T->getTypeClass() == Type::TypeOfExpr) T = cast(T)->getUnderlyingExpr()->getType(); const ConstantArrayType *CAT = cast(T); d872 1 a872 1 return nullptr; d889 1 a889 1 C, ".compoundliteral", nullptr, d970 1 a970 1 return nullptr; d1004 1 a1004 1 return nullptr; d1029 1 a1029 1 llvm::Constant *C = nullptr; d1066 1 a1066 3 unsigned AS = C->getType()->getPointerAddressSpace(); llvm::Type *CharPtrTy = Int8Ty->getPointerTo(AS); llvm::Constant *Casted = llvm::ConstantExpr::getBitCast(C, CharPtrTy); d1172 1 a1172 1 llvm::Constant *Filler = nullptr; d1178 1 a1178 1 llvm::Type *CommonElementType = nullptr; d1189 1 a1189 1 CommonElementType = nullptr; d1228 1 a1228 1 return ConstExprEmitter(*this, nullptr).EmitLValue(E); d1271 3 a1273 2 for (const auto &I : RD->bases()) { if (I.isVirtual()) { d1279 1 a1279 1 cast(I.getType()->getAs()->getDecl()); d1291 1 a1291 1 FillInNullDataMemberPointers(CGM, I.getType(), d1341 3 a1343 2 for (const auto &I : record->bases()) { if (I.isVirtual()) { d1350 1 a1350 1 cast(I.getType()->castAs()->getDecl()); d1362 4 a1365 1 for (const auto *Field : record->fields()) { d1368 3 a1370 3 if (!Field->isBitField()) { unsigned fieldIndex = layout.getLLVMFieldNo(Field); elements[fieldIndex] = CGM.EmitNullConstant(Field->getType()); d1374 1 a1374 1 if (record->isUnion() && Field->getDeclName()) d1380 2 a1381 1 for (const auto &I : record->vbases()) { d1383 1 a1383 1 cast(I.getType()->castAs()->getDecl()); @ 1.1.1.3 log @Import Clang 3.5svn r209886. @ text @d533 1 a533 1 return nullptr; d575 1 a575 1 return nullptr; d602 1 a602 1 if (!C) return nullptr; d663 1 a663 1 return nullptr; d704 1 a704 1 return nullptr; d746 1 a746 1 return nullptr; d759 1 a759 1 return nullptr; d792 1 a792 1 return nullptr; d797 1 a797 1 return nullptr; d809 2 a810 2 return nullptr; d839 1 a839 4 QualType T = E->getType(); if (T->getTypeClass() == Type::TypeOfExpr) T = cast(T)->getUnderlyingExpr()->getType(); const ConstantArrayType *CAT = cast(T); d872 1 a872 1 return nullptr; d889 1 a889 1 C, ".compoundliteral", nullptr, d970 1 a970 1 return nullptr; d1004 1 a1004 1 return nullptr; d1029 1 a1029 1 llvm::Constant *C = nullptr; d1066 1 a1066 3 unsigned AS = C->getType()->getPointerAddressSpace(); llvm::Type *CharPtrTy = Int8Ty->getPointerTo(AS); llvm::Constant *Casted = llvm::ConstantExpr::getBitCast(C, CharPtrTy); d1172 1 a1172 1 llvm::Constant *Filler = nullptr; d1178 1 a1178 1 llvm::Type *CommonElementType = nullptr; d1189 1 a1189 1 CommonElementType = nullptr; d1228 1 a1228 1 return ConstExprEmitter(*this, nullptr).EmitLValue(E); d1271 3 a1273 2 for (const auto &I : RD->bases()) { if (I.isVirtual()) { d1279 1 a1279 1 cast(I.getType()->getAs()->getDecl()); d1291 1 a1291 1 FillInNullDataMemberPointers(CGM, I.getType(), d1341 3 a1343 2 for (const auto &I : record->bases()) { if (I.isVirtual()) { d1350 1 a1350 1 cast(I.getType()->castAs()->getDecl()); d1362 4 a1365 1 for (const auto *Field : record->fields()) { d1368 3 a1370 3 if (!Field->isBitField()) { unsigned fieldIndex = layout.getLLVMFieldNo(Field); elements[fieldIndex] = CGM.EmitNullConstant(Field->getType()); d1374 1 a1374 1 if (record->isUnion() && Field->getDeclName()) d1380 2 a1381 1 for (const auto &I : record->vbases()) { d1383 1 a1383 1 cast(I.getType()->castAs()->getDecl()); @ 1.1.1.4 log @Import clang 3.6svn r215315. @ text @a1047 19 // For an _Atomic-qualified constant, we may need to add tail padding. if (auto *AT = DestType->getAs()) { QualType InnerType = AT->getValueType(); auto *Inner = EmitConstantValue(Value, InnerType, CGF); uint64_t InnerSize = Context.getTypeSize(InnerType); uint64_t OuterSize = Context.getTypeSize(DestType); if (InnerSize == OuterSize) return Inner; assert(InnerSize < OuterSize && "emitted over-large constant for atomic"); llvm::Constant *Elts[] = { Inner, llvm::ConstantAggregateZero::get( llvm::ArrayType::get(Int8Ty, (OuterSize - InnerSize) / 8)) }; return llvm::ConstantStruct::getAnon(Elts); } @ 1.1.1.4.2.1 log @Update LLVM to 3.6.1, requested by joerg in ticket 824. @ text @d107 10 a116 1 NextFieldOffsetInChars.RoundUpToAlignment(FieldAlignment); a124 18 AlignedNextFieldOffsetInChars = NextFieldOffsetInChars.RoundUpToAlignment(FieldAlignment); } if (AlignedNextFieldOffsetInChars > FieldOffsetInChars) { assert(!Packed && "Alignment is wrong even with a packed struct!"); // Convert the struct to a packed struct. ConvertStructToPacked(); // After we pack the struct, we may need to insert padding. if (NextFieldOffsetInChars < FieldOffsetInChars) { // We need to append padding. AppendPadding(FieldOffsetInChars - NextFieldOffsetInChars); assert(NextFieldOffsetInChars == FieldOffsetInChars && "Did not add enough padding!"); } d489 2 d492 1 a492 7 NextFieldOffsetInChars.RoundUpToAlignment(LLVMStructAlignment); if (LLVMSizeInChars != LayoutSizeInChars) AppendTailPadding(LayoutSizeInChars); LLVMSizeInChars = NextFieldOffsetInChars.RoundUpToAlignment(LLVMStructAlignment); d504 1 a504 4 LLVMSizeInChars = NextFieldOffsetInChars.RoundUpToAlignment(LLVMStructAlignment); assert(LayoutSizeInChars == LLVMSizeInChars && a736 14 // Initialize remaining array elements. // FIXME: This doesn't handle member pointers correctly! llvm::Constant *fillC; if (Expr *filler = ILE->getArrayFiller()) fillC = CGM.EmitConstantExpr(filler, filler->getType(), CGF); else fillC = llvm::Constant::getNullValue(ElemTy); if (!fillC) return nullptr; // Try to use a ConstantAggregateZero if we can. if (fillC->isNullValue() && !NumInitableElts) return llvm::ConstantAggregateZero::get(AType); d751 9 d872 1 a872 2 return CGM.getOrCreateStaticVarDecl( *VD, CGM.getLLVMLinkageVarDefinition(VD, /*isConstant=*/false)); d1129 1 a1129 1 nullptr); d1135 1 a1135 2 !Context.getLangOpts().NativeHalfType && !Context.getLangOpts().HalfArgsAndReturns) d1151 1 a1151 1 nullptr); d1192 3 d1202 1 a1202 12 llvm::Type *CommonElementType = getTypes().ConvertType(CAT->getElementType()); // Try to use a ConstantAggregateZero if we can. if (Filler && Filler->isNullValue() && !NumInitElts) { llvm::ArrayType *AType = llvm::ArrayType::get(CommonElementType, NumElements); return llvm::ConstantAggregateZero::get(AType); } std::vector Elts; Elts.reserve(NumElements); d1271 77 d1436 26 a1461 2 // Otherwise, we can just use its null constant. return EmitNullConstant(CGM, base, /*asCompleteObject=*/false); d1492 3 a1494 1 @ 1.1.1.5 log @Import Clang 3.6RC1 r227398. @ text @d107 10 a116 1 NextFieldOffsetInChars.RoundUpToAlignment(FieldAlignment); a124 18 AlignedNextFieldOffsetInChars = NextFieldOffsetInChars.RoundUpToAlignment(FieldAlignment); } if (AlignedNextFieldOffsetInChars > FieldOffsetInChars) { assert(!Packed && "Alignment is wrong even with a packed struct!"); // Convert the struct to a packed struct. ConvertStructToPacked(); // After we pack the struct, we may need to insert padding. if (NextFieldOffsetInChars < FieldOffsetInChars) { // We need to append padding. AppendPadding(FieldOffsetInChars - NextFieldOffsetInChars); assert(NextFieldOffsetInChars == FieldOffsetInChars && "Did not add enough padding!"); } d489 2 d492 1 a492 7 NextFieldOffsetInChars.RoundUpToAlignment(LLVMStructAlignment); if (LLVMSizeInChars != LayoutSizeInChars) AppendTailPadding(LayoutSizeInChars); LLVMSizeInChars = NextFieldOffsetInChars.RoundUpToAlignment(LLVMStructAlignment); d504 1 a504 4 LLVMSizeInChars = NextFieldOffsetInChars.RoundUpToAlignment(LLVMStructAlignment); assert(LayoutSizeInChars == LLVMSizeInChars && a736 14 // Initialize remaining array elements. // FIXME: This doesn't handle member pointers correctly! llvm::Constant *fillC; if (Expr *filler = ILE->getArrayFiller()) fillC = CGM.EmitConstantExpr(filler, filler->getType(), CGF); else fillC = llvm::Constant::getNullValue(ElemTy); if (!fillC) return nullptr; // Try to use a ConstantAggregateZero if we can. if (fillC->isNullValue() && !NumInitableElts) return llvm::ConstantAggregateZero::get(AType); d751 9 d872 1 a872 2 return CGM.getOrCreateStaticVarDecl( *VD, CGM.getLLVMLinkageVarDefinition(VD, /*isConstant=*/false)); d1129 1 a1129 1 nullptr); d1135 1 a1135 2 !Context.getLangOpts().NativeHalfType && !Context.getLangOpts().HalfArgsAndReturns) d1151 1 a1151 1 nullptr); d1192 3 d1202 1 a1202 12 llvm::Type *CommonElementType = getTypes().ConvertType(CAT->getElementType()); // Try to use a ConstantAggregateZero if we can. if (Filler && Filler->isNullValue() && !NumInitElts) { llvm::ArrayType *AType = llvm::ArrayType::get(CommonElementType, NumElements); return llvm::ConstantAggregateZero::get(AType); } std::vector Elts; Elts.reserve(NumElements); d1271 77 d1436 26 a1461 2 // Otherwise, we can just use its null constant. return EmitNullConstant(CGM, base, /*asCompleteObject=*/false); d1492 3 a1494 1 @ 1.1.1.6 log @Import Clang 3.8.0rc3 r261930. @ text @a35 1 class ConstExprEmitter; a44 4 static llvm::Constant *BuildStruct(CodeGenModule &CGM, CodeGenFunction *CFG, ConstExprEmitter *Emitter, llvm::ConstantStruct *Base, InitListExpr *Updater); a70 2 bool Build(ConstExprEmitter *Emitter, llvm::ConstantStruct *Base, InitListExpr *Updater); d386 1 a386 1 d392 2 a393 7 if (auto *CI = dyn_cast(EltInit)) { AppendBitField(*Field, Layout.getFieldOffset(FieldNo), CI); } else { // We are trying to initialize a bitfield with a non-trivial constant, // this must require run-time code. return false; } a544 11 ConstExprEmitter *Emitter, llvm::ConstantStruct *Base, InitListExpr *Updater) { ConstStructBuilder Builder(CGM, CGF); if (!Builder.Build(Emitter, Base, Updater)) return nullptr; return Builder.Finalize(Updater->getType()); } llvm::Constant *ConstStructBuilder::BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, a615 2 if (const auto *ECE = dyn_cast(E)) CGM.EmitExplicitCastExprType(ECE, CGF); a712 1 case CK_BooleanToSignedIntegral: a815 76 llvm::Constant *EmitDesignatedInitUpdater(llvm::Constant *Base, InitListExpr *Updater) { QualType ExprType = Updater->getType(); if (ExprType->isArrayType()) { llvm::ArrayType *AType = cast(ConvertType(ExprType)); llvm::Type *ElemType = AType->getElementType(); unsigned NumInitElements = Updater->getNumInits(); unsigned NumElements = AType->getNumElements(); std::vector Elts; Elts.reserve(NumElements); if (llvm::ConstantDataArray *DataArray = dyn_cast(Base)) for (unsigned i = 0; i != NumElements; ++i) Elts.push_back(DataArray->getElementAsConstant(i)); else if (llvm::ConstantArray *Array = dyn_cast(Base)) for (unsigned i = 0; i != NumElements; ++i) Elts.push_back(Array->getOperand(i)); else return nullptr; // FIXME: other array types not implemented llvm::Constant *fillC = nullptr; if (Expr *filler = Updater->getArrayFiller()) if (!isa(filler)) fillC = CGM.EmitConstantExpr(filler, filler->getType(), CGF); bool RewriteType = (fillC && fillC->getType() != ElemType); for (unsigned i = 0; i != NumElements; ++i) { Expr *Init = nullptr; if (i < NumInitElements) Init = Updater->getInit(i); if (!Init && fillC) Elts[i] = fillC; else if (!Init || isa(Init)) ; // Do nothing. else if (InitListExpr *ChildILE = dyn_cast(Init)) Elts[i] = EmitDesignatedInitUpdater(Elts[i], ChildILE); else Elts[i] = CGM.EmitConstantExpr(Init, Init->getType(), CGF); if (!Elts[i]) return nullptr; RewriteType |= (Elts[i]->getType() != ElemType); } if (RewriteType) { std::vector Types; Types.reserve(NumElements); for (unsigned i = 0; i != NumElements; ++i) Types.push_back(Elts[i]->getType()); llvm::StructType *SType = llvm::StructType::get(AType->getContext(), Types, true); return llvm::ConstantStruct::get(SType, Elts); } return llvm::ConstantArray::get(AType, Elts); } if (ExprType->isRecordType()) return ConstStructBuilder::BuildStruct(CGM, CGF, this, dyn_cast(Base), Updater); return nullptr; } llvm::Constant *VisitDesignatedInitUpdateExpr(DesignatedInitUpdateExpr *E) { return EmitDesignatedInitUpdater( CGM.EmitConstantExpr(E->getBase(), E->getType(), CGF), E->getUpdater()); } d881 1 a881 1 ConstantAddress EmitLValue(APValue::LValueBase LVBase) { d886 1 a886 1 return ConstantAddress(CGM.GetAddrOfFunction(FD), CharUnits::One()); a889 1 CharUnits Align = CGM.getContext().getDeclAlign(VD); d891 3 a893 3 return ConstantAddress(CGM.GetAddrOfGlobalVar(VD), Align); else if (VD->isLocalVarDecl()) { auto Ptr = CGM.getOrCreateStaticVarDecl( a894 2 return ConstantAddress(Ptr, Align); } d897 1 a897 1 return ConstantAddress::invalid(); d910 2 a911 5 if (!C) return ConstantAddress::invalid(); CharUnits Align = CGM.getContext().getTypeAlignInChars(E->getType()); auto GV = new llvm::GlobalVariable(CGM.getModule(), C->getType(), d917 1 a917 2 GV->setAlignment(Align.getQuantity()); return ConstantAddress(GV, Align); d925 1 a925 1 ConstantAddress C = d927 1 a927 1 return C.getElementBitCast(ConvertType(E->getType())); d933 1 a933 1 return cast(Res.getAddress()); d944 1 a944 2 Ptr = llvm::ConstantExpr::getBitCast(Ptr, ConvertType(E->getType())); return ConstantAddress(Ptr, CharUnits::One()); d970 1 a970 4 // This is not really an l-value. llvm::Constant *Ptr = CGM.GetAddrOfGlobalBlock(cast(E), FunctionName.c_str()); return ConstantAddress(Ptr, CGM.getPointerAlign()); d979 1 a979 2 return ConstantAddress(CGM.GetAddrOfRTTIDescriptor(T), CGM.getPointerAlign()); d995 1 a995 1 return ConstantAddress::invalid(); a1000 62 bool ConstStructBuilder::Build(ConstExprEmitter *Emitter, llvm::ConstantStruct *Base, InitListExpr *Updater) { assert(Base && "base expression should not be empty"); QualType ExprType = Updater->getType(); RecordDecl *RD = ExprType->getAs()->getDecl(); const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); const llvm::StructLayout *BaseLayout = CGM.getDataLayout().getStructLayout( Base->getType()); unsigned FieldNo = -1; unsigned ElementNo = 0; for (FieldDecl *Field : RD->fields()) { ++FieldNo; if (RD->isUnion() && Updater->getInitializedFieldInUnion() != Field) continue; // Skip anonymous bitfields. if (Field->isUnnamedBitfield()) continue; llvm::Constant *EltInit = Base->getOperand(ElementNo); // Bail out if the type of the ConstantStruct does not have the same layout // as the type of the InitListExpr. if (CGM.getTypes().ConvertType(Field->getType()) != EltInit->getType() || Layout.getFieldOffset(ElementNo) != BaseLayout->getElementOffsetInBits(ElementNo)) return false; // Get the initializer. If we encounter an empty field or a NoInitExpr, // we use values from the base expression. Expr *Init = nullptr; if (ElementNo < Updater->getNumInits()) Init = Updater->getInit(ElementNo); if (!Init || isa(Init)) ; // Do nothing. else if (InitListExpr *ChildILE = dyn_cast(Init)) EltInit = Emitter->EmitDesignatedInitUpdater(EltInit, ChildILE); else EltInit = CGM.EmitConstantExpr(Init, Field->getType(), CGF); ++ElementNo; if (!EltInit) return false; if (!Field->isBitField()) AppendField(Field, Layout.getFieldOffset(FieldNo), EltInit); else if (llvm::ConstantInt *CI = dyn_cast(EltInit)) AppendBitField(Field, Layout.getFieldOffset(FieldNo), CI); else // Initializing a bitfield with a non-trivial constant? return false; } return true; } d1097 1 a1097 1 llvm::Constant *C = nullptr; d1106 1 a1106 1 C = ConstExprEmitter(*this, CGF).EmitLValue(LVBase).getPointer(); d1113 1 a1113 1 Casted = llvm::ConstantExpr::getGetElementPtr(Int8Ty, Casted, Offset); d1178 1 a1179 1 SmallVector Inits(NumElts); d1181 2 a1182 2 for (unsigned I = 0; I != NumElts; ++I) { const APValue &Elt = Value.getVectorElt(I); d1184 1 a1184 3 Inits[I] = llvm::ConstantInt::get(VMContext, Elt.getInt()); else if (Elt.isFloat()) Inits[I] = llvm::ConstantFP::get(VMContext, Elt.getFloat()); d1186 1 a1186 1 llvm_unreachable("unsupported vector element type"); d1280 1 a1280 1 ConstantAddress d1294 1 a1294 1 return getCXXABI().EmitMemberFunctionPointer(method); d1347 2 a1348 8 if (record->isUnion()) { if (Field->getIdentifier()) break; if (const auto *FieldRD = dyn_cast_or_null(Field->getType()->getAsTagDecl())) if (FieldRD->findFirstNamedDataMember()) break; } d1406 4 d1419 2 a1420 1 assert(T->isMemberDataPointerType() && @ 1.1.1.6.2.1 log @Sync with HEAD @ text @a18 1 #include "TargetInfo.h" d114 1 a114 1 NextFieldOffsetInChars.alignTo(FieldAlignment); d124 1 a124 1 NextFieldOffsetInChars.alignTo(FieldAlignment); d165 2 a166 2 llvm::alignTo(FieldOffset - NextFieldOffsetInBits, Context.getTargetInfo().getCharAlign())); d337 1 a337 1 ElementOffsetInChars.alignTo(ElementAlign); d371 1 a371 8 // Bail out if we have base classes. We could support these, but they only // arise in C++1z where we will have already constant folded most interesting // cases. FIXME: There are still a few more cases we can handle this way. if (auto *CXXRD = dyn_cast(RD)) if (CXXRD->getNumBases()) return false; d511 1 a511 1 NextFieldOffsetInChars.alignTo(LLVMStructAlignment); d516 2 a517 1 LLVMSizeInChars = NextFieldOffsetInChars.alignTo(LLVMStructAlignment); d529 2 a530 1 LLVMSizeInChars = NextFieldOffsetInChars.alignTo(LLVMStructAlignment); d549 2 a550 3 assert(NextFieldOffsetInChars.alignTo(getAlignment(Result)) == getSizeInChars(Result) && "Size mismatch!"); a686 3 case CK_IntToOCLSampler: llvm_unreachable("global sampler variables are not generated"); a745 1 case CK_ZeroToOCLQueue: a760 6 llvm::Constant *VisitExprWithCleanups(ExprWithCleanups *E) { if (!E->cleanupsHaveSideEffects()) return Visit(E->getSubExpr()); return nullptr; } d766 3 a832 3 if (ILE->isTransparent()) return Visit(ILE->getInit(0)); d1009 2 a1011 5 CharUnits Align = CGM.getContext().getTypeAlignInChars(E->getType()); if (llvm::GlobalVariable *Addr = CGM.getAddrOfConstantCompoundLiteralIfEmitted(CLE)) return ConstantAddress(Addr, Align); d1017 2 a1025 1 CGM.setAddrOfConstantCompoundLiteral(CLE, GV); d1074 1 a1074 1 StringRef FunctionName; d1082 1 a1082 1 CGM.GetAddrOfGlobalBlock(cast(E), FunctionName); a1127 7 // Bail out if we have base classes. We could support these, but they only // arise in C++1z where we will have already constant folded most interesting // cases. FIXME: There are still a few more cases we can handle this way. if (auto *CXXRD = dyn_cast(RD)) if (CXXRD->getNumBases()) return false; a1242 4 llvm::Constant *CodeGenModule::getNullPointer(llvm::PointerType *T, QualType QT) { return getTargetCodeGenInfo().getNullPointer(*this, T, QT); } a1273 1 d1304 1 a1304 8 if (auto PT = dyn_cast(DestTy)) { if (Value.isNullPointer()) return getNullPointer(PT, DestType); // Convert the integer to a pointer-sized integer before converting it // to a pointer. C = llvm::ConstantExpr::getIntegerCast( C, getDataLayout().getIntPtrType(DestTy), /*isSigned=*/false); a1305 1 } d1332 1 a1332 1 if (&Init.getSemantics() == &llvm::APFloat::IEEEhalf() && a1457 12 llvm::GlobalVariable *CodeGenModule::getAddrOfConstantCompoundLiteralIfEmitted( const CompoundLiteralExpr *E) { return EmittedCompoundLiterals.lookup(E); } void CodeGenModule::setAddrOfConstantCompoundLiteral( const CompoundLiteralExpr *CLE, llvm::GlobalVariable *GV) { bool Ok = EmittedCompoundLiterals.insert(std::make_pair(CLE, GV)).second; (void)Ok; assert(Ok && "CLE has already been emitted!"); } d1485 1 a1485 1 const RecordDecl *record, a1494 1 auto CXXR = dyn_cast(record); d1496 6 a1501 10 if (CXXR) { for (const auto &I : CXXR->bases()) { if (I.isVirtual()) { // Ignore virtual bases; if we're laying out for a complete // object, we'll lay these out later. continue; } const CXXRecordDecl *base = cast(I.getType()->castAs()->getDecl()); d1503 2 a1504 5 // Ignore empty bases. if (base->isEmpty() || CGM.getContext().getASTRecordLayout(base).getNonVirtualSize() .isZero()) continue; d1506 7 a1512 4 unsigned fieldIndex = layout.getNonVirtualBaseLLVMFieldNo(base); llvm::Type *baseType = structure->getElementType(fieldIndex); elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base); } d1536 2 a1537 2 if (CXXR && asCompleteObject) { for (const auto &I : CXXR->vbases()) { a1578 4 if (T->getAs()) return getNullPointer( cast(getTypes().ConvertTypeForMem(T)), T); d1594 4 a1597 2 if (const RecordType *RT = T->getAs()) return ::EmitNullConstant(*this, RT->getDecl(), /*complete object*/ true); @ 1.1.1.7 log @Import Clang pre-4.0.0 r291444. @ text @a18 1 #include "TargetInfo.h" d114 1 a114 1 NextFieldOffsetInChars.alignTo(FieldAlignment); d124 1 a124 1 NextFieldOffsetInChars.alignTo(FieldAlignment); d165 2 a166 2 llvm::alignTo(FieldOffset - NextFieldOffsetInBits, Context.getTargetInfo().getCharAlign())); d337 1 a337 1 ElementOffsetInChars.alignTo(ElementAlign); d371 1 a371 8 // Bail out if we have base classes. We could support these, but they only // arise in C++1z where we will have already constant folded most interesting // cases. FIXME: There are still a few more cases we can handle this way. if (auto *CXXRD = dyn_cast(RD)) if (CXXRD->getNumBases()) return false; d511 1 a511 1 NextFieldOffsetInChars.alignTo(LLVMStructAlignment); d516 2 a517 1 LLVMSizeInChars = NextFieldOffsetInChars.alignTo(LLVMStructAlignment); d529 2 a530 1 LLVMSizeInChars = NextFieldOffsetInChars.alignTo(LLVMStructAlignment); d549 2 a550 3 assert(NextFieldOffsetInChars.alignTo(getAlignment(Result)) == getSizeInChars(Result) && "Size mismatch!"); a686 3 case CK_IntToOCLSampler: llvm_unreachable("global sampler variables are not generated"); a745 1 case CK_ZeroToOCLQueue: a760 6 llvm::Constant *VisitExprWithCleanups(ExprWithCleanups *E) { if (!E->cleanupsHaveSideEffects()) return Visit(E->getSubExpr()); return nullptr; } d766 3 a832 3 if (ILE->isTransparent()) return Visit(ILE->getInit(0)); d1009 2 a1011 5 CharUnits Align = CGM.getContext().getTypeAlignInChars(E->getType()); if (llvm::GlobalVariable *Addr = CGM.getAddrOfConstantCompoundLiteralIfEmitted(CLE)) return ConstantAddress(Addr, Align); d1017 2 a1025 1 CGM.setAddrOfConstantCompoundLiteral(CLE, GV); d1074 1 a1074 1 StringRef FunctionName; d1082 1 a1082 1 CGM.GetAddrOfGlobalBlock(cast(E), FunctionName); a1127 7 // Bail out if we have base classes. We could support these, but they only // arise in C++1z where we will have already constant folded most interesting // cases. FIXME: There are still a few more cases we can handle this way. if (auto *CXXRD = dyn_cast(RD)) if (CXXRD->getNumBases()) return false; a1242 4 llvm::Constant *CodeGenModule::getNullPointer(llvm::PointerType *T, QualType QT) { return getTargetCodeGenInfo().getNullPointer(*this, T, QT); } a1273 1 d1304 1 a1304 8 if (auto PT = dyn_cast(DestTy)) { if (Value.isNullPointer()) return getNullPointer(PT, DestType); // Convert the integer to a pointer-sized integer before converting it // to a pointer. C = llvm::ConstantExpr::getIntegerCast( C, getDataLayout().getIntPtrType(DestTy), /*isSigned=*/false); a1305 1 } d1332 1 a1332 1 if (&Init.getSemantics() == &llvm::APFloat::IEEEhalf() && a1457 12 llvm::GlobalVariable *CodeGenModule::getAddrOfConstantCompoundLiteralIfEmitted( const CompoundLiteralExpr *E) { return EmittedCompoundLiterals.lookup(E); } void CodeGenModule::setAddrOfConstantCompoundLiteral( const CompoundLiteralExpr *CLE, llvm::GlobalVariable *GV) { bool Ok = EmittedCompoundLiterals.insert(std::make_pair(CLE, GV)).second; (void)Ok; assert(Ok && "CLE has already been emitted!"); } d1485 1 a1485 1 const RecordDecl *record, a1494 1 auto CXXR = dyn_cast(record); d1496 6 a1501 10 if (CXXR) { for (const auto &I : CXXR->bases()) { if (I.isVirtual()) { // Ignore virtual bases; if we're laying out for a complete // object, we'll lay these out later. continue; } const CXXRecordDecl *base = cast(I.getType()->castAs()->getDecl()); d1503 2 a1504 5 // Ignore empty bases. if (base->isEmpty() || CGM.getContext().getASTRecordLayout(base).getNonVirtualSize() .isZero()) continue; d1506 7 a1512 4 unsigned fieldIndex = layout.getNonVirtualBaseLLVMFieldNo(base); llvm::Type *baseType = structure->getElementType(fieldIndex); elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base); } d1536 2 a1537 2 if (CXXR && asCompleteObject) { for (const auto &I : CXXR->vbases()) { a1578 4 if (T->getAs()) return getNullPointer( cast(getTypes().ConvertTypeForMem(T)), T); d1594 4 a1597 2 if (const RecordType *RT = T->getAs()) return ::EmitNullConstant(*this, RT->getDecl(), /*complete object*/ true); @ 1.1.1.8 log @Import clang r309604 from branches/release_50 @ text @d204 1 a204 1 Tmp.lshrInPlace(NewFieldWidth); d213 1 a213 1 FieldValue.lshrInPlace(BitsInPreviousByte); d276 1 a276 1 FieldValue.lshrInPlace(CharWidth); d1364 3 a1366 2 llvm::StructType *STy = llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType()); d1387 3 a1389 2 llvm::StructType *STy = llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType()); @ 1.1.1.8.4.1 log @Sync with HEAD @ text @a18 1 #include "ConstantEmitter.h" d40 1 a40 1 ConstantEmitter &Emitter; d47 2 a48 2 static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, ConstExprEmitter *ExprEmitter, d50 4 a53 5 InitListExpr *Updater, QualType ValTy); static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, InitListExpr *ILE, QualType StructTy); static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, d57 2 a58 2 ConstStructBuilder(ConstantEmitter &emitter) : CGM(emitter.CGM), Emitter(emitter), Packed(false), d79 1 a79 1 bool Build(const APValue &Val, const RecordDecl *RD, bool IsPrimaryBase, d394 2 a395 2 EltInit = Emitter.tryEmitPrivateForMemory(ILE->getInit(ElementNo++), Field->getType()); d397 1 a397 1 EltInit = Emitter.emitNullForMemory(Field->getType()); d434 1 a434 1 bool ConstStructBuilder::Build(const APValue &Val, const RecordDecl *RD, d489 2 a490 3 Emitter.tryEmitPrivateForMemory(FieldValue, Field->getType()); if (!EltInit) return false; a500 2 return true; d562 3 a564 2 llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, ConstExprEmitter *ExprEmitter, d566 3 a568 4 InitListExpr *Updater, QualType ValTy) { ConstStructBuilder Builder(Emitter); if (!Builder.Build(ExprEmitter, Base, Updater)) d570 1 a570 1 return Builder.Finalize(ValTy); d573 4 a576 4 llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, InitListExpr *ILE, QualType ValTy) { ConstStructBuilder Builder(Emitter); d581 1 a581 1 return Builder.Finalize(ValTy); d584 2 a585 1 llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, d588 1 a588 1 ConstStructBuilder Builder(Emitter); d592 1 a592 2 if (!Builder.Build(Val, RD, false, CD, CharUnits::Zero())) return nullptr; a601 85 static ConstantAddress tryEmitGlobalCompoundLiteral(CodeGenModule &CGM, CodeGenFunction *CGF, const CompoundLiteralExpr *E) { CharUnits Align = CGM.getContext().getTypeAlignInChars(E->getType()); if (llvm::GlobalVariable *Addr = CGM.getAddrOfConstantCompoundLiteralIfEmitted(E)) return ConstantAddress(Addr, Align); LangAS addressSpace = E->getType().getAddressSpace(); ConstantEmitter emitter(CGM, CGF); llvm::Constant *C = emitter.tryEmitForInitializer(E->getInitializer(), addressSpace, E->getType()); if (!C) { assert(!E->isFileScope() && "file-scope compound literal did not have constant initializer!"); return ConstantAddress::invalid(); } auto GV = new llvm::GlobalVariable(CGM.getModule(), C->getType(), CGM.isTypeConstant(E->getType(), true), llvm::GlobalValue::InternalLinkage, C, ".compoundliteral", nullptr, llvm::GlobalVariable::NotThreadLocal, CGM.getContext().getTargetAddressSpace(addressSpace)); emitter.finalize(GV); GV->setAlignment(Align.getQuantity()); CGM.setAddrOfConstantCompoundLiteral(E, GV); return ConstantAddress(GV, Align); } static llvm::Constant * EmitArrayConstant(CodeGenModule &CGM, const ConstantArrayType *DestType, llvm::Type *CommonElementType, unsigned ArrayBound, SmallVectorImpl &Elements, llvm::Constant *Filler) { // Figure out how long the initial prefix of non-zero elements is. unsigned NonzeroLength = ArrayBound; if (Elements.size() < NonzeroLength && Filler->isNullValue()) NonzeroLength = Elements.size(); if (NonzeroLength == Elements.size()) { while (NonzeroLength > 0 && Elements[NonzeroLength - 1]->isNullValue()) --NonzeroLength; } if (NonzeroLength == 0) { return llvm::ConstantAggregateZero::get( CGM.getTypes().ConvertType(QualType(DestType, 0))); } // Add a zeroinitializer array filler if we have lots of trailing zeroes. unsigned TrailingZeroes = ArrayBound - NonzeroLength; if (TrailingZeroes >= 8) { assert(Elements.size() >= NonzeroLength && "missing initializer for non-zero element"); Elements.resize(NonzeroLength + 1); auto *FillerType = CommonElementType ? CommonElementType : CGM.getTypes().ConvertType(DestType->getElementType()); FillerType = llvm::ArrayType::get(FillerType, TrailingZeroes); Elements.back() = llvm::ConstantAggregateZero::get(FillerType); CommonElementType = nullptr; } else if (Elements.size() != ArrayBound) { // Otherwise pad to the right size with the filler if necessary. Elements.resize(ArrayBound, Filler); if (Filler->getType() != CommonElementType) CommonElementType = nullptr; } // If all elements have the same type, just emit an array constant. if (CommonElementType) return llvm::ConstantArray::get( llvm::ArrayType::get(CommonElementType, ArrayBound), Elements); // We have mixed types. Use a packed struct. llvm::SmallVector Types; Types.reserve(Elements.size()); for (llvm::Constant *Elt : Elements) Types.push_back(Elt->getType()); llvm::StructType *SType = llvm::StructType::get(CGM.getLLVMContext(), Types, true); return llvm::ConstantStruct::get(SType, Elements); } d607 1 a607 1 public StmtVisitor { d609 1 a609 1 ConstantEmitter &Emitter; d612 2 a613 2 ConstExprEmitter(ConstantEmitter &emitter) : CGM(emitter.CGM), Emitter(emitter), VMContext(CGM.getLLVMContext()) { d620 1 a620 1 llvm::Constant *VisitStmt(Stmt *S, QualType T) { d624 2 a625 2 llvm::Constant *VisitParenExpr(ParenExpr *PE, QualType T) { return Visit(PE->getSubExpr(), T); d629 2 a630 3 VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE, QualType T) { return Visit(PE->getReplacement(), T); d633 2 a634 3 llvm::Constant *VisitGenericSelectionExpr(GenericSelectionExpr *GE, QualType T) { return Visit(GE->getResultExpr(), T); d637 2 a638 2 llvm::Constant *VisitChooseExpr(ChooseExpr *CE, QualType T) { return Visit(CE->getChosenSubExpr(), T); d641 2 a642 2 llvm::Constant *VisitCompoundLiteralExpr(CompoundLiteralExpr *E, QualType T) { return Visit(E->getInitializer(), T); d645 1 a645 1 llvm::Constant *VisitCastExpr(CastExpr *E, QualType destType) { d647 1 a647 1 CGM.EmitExplicitCastExprType(ECE, Emitter.CGF); d649 4 a659 8 auto field = E->getTargetUnionField(); auto C = Emitter.tryEmitPrivateForMemory(subExpr, field->getType()); if (!C) return nullptr; auto destTy = ConvertType(destType); if (C->getType() == destTy) return C; d661 1 a661 1 // and padded to the appropriate size. d667 1 a667 1 unsigned TotalSize = CGM.getDataLayout().getTypeAllocSize(destTy); d679 2 a680 1 llvm::StructType *STy = llvm::StructType::get(VMContext, Types, false); d684 2 a685 9 case CK_AddressSpaceConversion: { auto C = Emitter.tryEmitPrivate(subExpr, subExpr->getType()); if (!C) return nullptr; LangAS destAS = E->getType()->getPointeeType().getAddressSpace(); LangAS srcAS = subExpr->getType()->getPointeeType().getAddressSpace(); llvm::Type *destTy = ConvertType(E->getType()); return CGM.getTargetCodeGenInfo().performAddrSpaceCast(CGM, C, srcAS, destAS, destTy); } d692 1 a692 1 return Visit(subExpr, destType); d704 1 a704 3 case CK_BaseToDerivedMemberPointer: { auto C = Emitter.tryEmitPrivate(subExpr, subExpr->getType()); if (!C) return nullptr; a705 1 } d762 2 a763 2 llvm::Constant *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE, QualType T) { return Visit(DAE->getExpr(), T); d766 1 a766 1 llvm::Constant *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE, QualType T) { d769 1 a769 1 return Visit(DIE->getExpr(), T); d772 1 a772 1 llvm::Constant *VisitExprWithCleanups(ExprWithCleanups *E, QualType T) { d774 1 a774 1 return Visit(E->getSubExpr(), T); d778 2 a779 3 llvm::Constant *VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E, QualType T) { return Visit(E->GetTemporaryExpr(), T); d782 4 a785 3 llvm::Constant *EmitArrayInitialization(InitListExpr *ILE, QualType T) { auto *CAT = CGM.getContext().getAsConstantArrayType(ILE->getType()); assert(CAT && "can't emit array init for non-constant-bound array"); d787 1 a787 1 unsigned NumElements = CAT->getSize().getZExtValue(); d793 9 a801 1 QualType EltType = CAT->getElementType(); d803 3 a805 7 // Initialize remaining array elements. llvm::Constant *fillC = nullptr; if (Expr *filler = ILE->getArrayFiller()) { fillC = Emitter.tryEmitAbstractForMemory(filler, EltType); if (!fillC) return nullptr; } d808 2 a809 5 SmallVector Elts; if (fillC && fillC->isNullValue()) Elts.reserve(NumInitableElts + 1); else Elts.reserve(NumElements); d811 1 a811 1 llvm::Type *CommonElementType = nullptr; d814 1 a814 1 llvm::Constant *C = Emitter.tryEmitPrivateForMemory(Init, EltType); d817 1 a817 4 if (i == 0) CommonElementType = C->getType(); else if (C->getType() != CommonElementType) CommonElementType = nullptr; d821 15 a835 2 return EmitArrayConstant(CGM, CAT, CommonElementType, NumElements, Elts, fillC); d838 2 a839 2 llvm::Constant *EmitRecordInitialization(InitListExpr *ILE, QualType T) { return ConstStructBuilder::BuildStruct(Emitter, ILE, T); d842 2 a843 3 llvm::Constant *VisitImplicitValueInitExpr(ImplicitValueInitExpr* E, QualType T) { return CGM.EmitNullConstant(T); d846 1 a846 1 llvm::Constant *VisitInitListExpr(InitListExpr *ILE, QualType T) { d848 1 a848 1 return Visit(ILE->getInit(0), T); d851 1 a851 1 return EmitArrayInitialization(ILE, T); d854 1 a854 1 return EmitRecordInitialization(ILE, T); d860 5 a864 4 InitListExpr *Updater, QualType destType) { if (auto destAT = CGM.getContext().getAsArrayType(destType)) { llvm::ArrayType *AType = cast(ConvertType(destType)); d873 2 a874 3 QualType destElemType = destAT->getElementType(); if (auto DataArray = dyn_cast(Base)) d877 2 a878 1 else if (auto Array = dyn_cast(Base)) d887 1 a887 1 fillC = Emitter.tryEmitAbstractForMemory(filler, destElemType); d900 1 a900 1 Elts[i] = EmitDesignatedInitUpdater(Elts[i], ChildILE, destElemType); d902 1 a902 1 Elts[i] = Emitter.tryEmitPrivateForMemory(Init, destElemType); d922 3 a924 3 if (destType->isRecordType()) return ConstStructBuilder::BuildStruct(Emitter, this, dyn_cast(Base), Updater, destType); d929 4 a932 5 llvm::Constant *VisitDesignatedInitUpdateExpr(DesignatedInitUpdateExpr *E, QualType destType) { auto C = Visit(E->getBase(), destType); if (!C) return nullptr; return EmitDesignatedInitUpdater(C, E->getUpdater(), destType); d935 1 a935 1 llvm::Constant *VisitCXXConstructExpr(CXXConstructExpr *E, QualType Ty) { d939 2 d963 1 a963 1 return Visit(Arg, Ty); d969 1 a969 1 llvm::Constant *VisitStringLiteral(StringLiteral *E, QualType T) { d973 1 a973 1 llvm::Constant *VisitObjCEncodeExpr(ObjCEncodeExpr *E, QualType T) { d979 4 a982 1 const ConstantArrayType *CAT = CGM.getContext().getAsConstantArrayType(T); d990 2 a991 2 llvm::Constant *VisitUnaryExtension(const UnaryOperator *E, QualType T) { return Visit(E->getSubExpr(), T); d998 132 d1134 1 a1134 1 bool ConstStructBuilder::Build(ConstExprEmitter *ExprEmitter, d1182 1 a1182 2 EltInit = ExprEmitter->EmitDesignatedInitUpdater(EltInit, ChildILE, Field->getType()); d1184 1 a1184 1 EltInit = Emitter.tryEmitPrivateForMemory(Init, Field->getType()); d1203 2 a1204 267 llvm::Constant *ConstantEmitter::validateAndPopAbstract(llvm::Constant *C, AbstractState saved) { Abstract = saved.OldValue; assert(saved.OldPlaceholdersSize == PlaceholderAddresses.size() && "created a placeholder while doing an abstract emission?"); // No validation necessary for now. // No cleanup to do for now. return C; } llvm::Constant * ConstantEmitter::tryEmitAbstractForInitializer(const VarDecl &D) { auto state = pushAbstract(); auto C = tryEmitPrivateForVarInit(D); return validateAndPopAbstract(C, state); } llvm::Constant * ConstantEmitter::tryEmitAbstract(const Expr *E, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(E, destType); return validateAndPopAbstract(C, state); } llvm::Constant * ConstantEmitter::tryEmitAbstract(const APValue &value, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(value, destType); return validateAndPopAbstract(C, state); } llvm::Constant * ConstantEmitter::emitAbstract(const Expr *E, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(E, destType); C = validateAndPopAbstract(C, state); if (!C) { CGM.Error(E->getExprLoc(), "internal error: could not emit constant value \"abstractly\""); C = CGM.EmitNullConstant(destType); } return C; } llvm::Constant * ConstantEmitter::emitAbstract(SourceLocation loc, const APValue &value, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(value, destType); C = validateAndPopAbstract(C, state); if (!C) { CGM.Error(loc, "internal error: could not emit constant value \"abstractly\""); C = CGM.EmitNullConstant(destType); } return C; } llvm::Constant *ConstantEmitter::tryEmitForInitializer(const VarDecl &D) { initializeNonAbstract(D.getType().getAddressSpace()); return markIfFailed(tryEmitPrivateForVarInit(D)); } llvm::Constant *ConstantEmitter::tryEmitForInitializer(const Expr *E, LangAS destAddrSpace, QualType destType) { initializeNonAbstract(destAddrSpace); return markIfFailed(tryEmitPrivateForMemory(E, destType)); } llvm::Constant *ConstantEmitter::emitForInitializer(const APValue &value, LangAS destAddrSpace, QualType destType) { initializeNonAbstract(destAddrSpace); auto C = tryEmitPrivateForMemory(value, destType); assert(C && "couldn't emit constant value non-abstractly?"); return C; } llvm::GlobalValue *ConstantEmitter::getCurrentAddrPrivate() { assert(!Abstract && "cannot get current address for abstract constant"); // Make an obviously ill-formed global that should blow up compilation // if it survives. auto global = new llvm::GlobalVariable(CGM.getModule(), CGM.Int8Ty, true, llvm::GlobalValue::PrivateLinkage, /*init*/ nullptr, /*name*/ "", /*before*/ nullptr, llvm::GlobalVariable::NotThreadLocal, CGM.getContext().getTargetAddressSpace(DestAddressSpace)); PlaceholderAddresses.push_back(std::make_pair(nullptr, global)); return global; } void ConstantEmitter::registerCurrentAddrPrivate(llvm::Constant *signal, llvm::GlobalValue *placeholder) { assert(!PlaceholderAddresses.empty()); assert(PlaceholderAddresses.back().first == nullptr); assert(PlaceholderAddresses.back().second == placeholder); PlaceholderAddresses.back().first = signal; } namespace { struct ReplacePlaceholders { CodeGenModule &CGM; /// The base address of the global. llvm::Constant *Base; llvm::Type *BaseValueTy = nullptr; /// The placeholder addresses that were registered during emission. llvm::DenseMap PlaceholderAddresses; /// The locations of the placeholder signals. llvm::DenseMap Locations; /// The current index stack. We use a simple unsigned stack because /// we assume that placeholders will be relatively sparse in the /// initializer, but we cache the index values we find just in case. llvm::SmallVector Indices; llvm::SmallVector IndexValues; ReplacePlaceholders(CodeGenModule &CGM, llvm::Constant *base, ArrayRef> addresses) : CGM(CGM), Base(base), PlaceholderAddresses(addresses.begin(), addresses.end()) { } void replaceInInitializer(llvm::Constant *init) { // Remember the type of the top-most initializer. BaseValueTy = init->getType(); // Initialize the stack. Indices.push_back(0); IndexValues.push_back(nullptr); // Recurse into the initializer. findLocations(init); // Check invariants. assert(IndexValues.size() == Indices.size() && "mismatch"); assert(Indices.size() == 1 && "didn't pop all indices"); // Do the replacement; this basically invalidates 'init'. assert(Locations.size() == PlaceholderAddresses.size() && "missed a placeholder?"); // We're iterating over a hashtable, so this would be a source of // non-determinism in compiler output *except* that we're just // messing around with llvm::Constant structures, which never itself // does anything that should be visible in compiler output. for (auto &entry : Locations) { assert(entry.first->getParent() == nullptr && "not a placeholder!"); entry.first->replaceAllUsesWith(entry.second); entry.first->eraseFromParent(); } } private: void findLocations(llvm::Constant *init) { // Recurse into aggregates. if (auto agg = dyn_cast(init)) { for (unsigned i = 0, e = agg->getNumOperands(); i != e; ++i) { Indices.push_back(i); IndexValues.push_back(nullptr); findLocations(agg->getOperand(i)); IndexValues.pop_back(); Indices.pop_back(); } return; } // Otherwise, check for registered constants. while (true) { auto it = PlaceholderAddresses.find(init); if (it != PlaceholderAddresses.end()) { setLocation(it->second); break; } // Look through bitcasts or other expressions. if (auto expr = dyn_cast(init)) { init = expr->getOperand(0); } else { break; } } } void setLocation(llvm::GlobalVariable *placeholder) { assert(Locations.find(placeholder) == Locations.end() && "already found location for placeholder!"); // Lazily fill in IndexValues with the values from Indices. // We do this in reverse because we should always have a strict // prefix of indices from the start. assert(Indices.size() == IndexValues.size()); for (size_t i = Indices.size() - 1; i != size_t(-1); --i) { if (IndexValues[i]) { #ifndef NDEBUG for (size_t j = 0; j != i + 1; ++j) { assert(IndexValues[j] && isa(IndexValues[j]) && cast(IndexValues[j])->getZExtValue() == Indices[j]); } #endif break; } IndexValues[i] = llvm::ConstantInt::get(CGM.Int32Ty, Indices[i]); } // Form a GEP and then bitcast to the placeholder type so that the // replacement will succeed. llvm::Constant *location = llvm::ConstantExpr::getInBoundsGetElementPtr(BaseValueTy, Base, IndexValues); location = llvm::ConstantExpr::getBitCast(location, placeholder->getType()); Locations.insert({placeholder, location}); } }; } void ConstantEmitter::finalize(llvm::GlobalVariable *global) { assert(InitializedNonAbstract && "finalizing emitter that was used for abstract emission?"); assert(!Finalized && "finalizing emitter multiple times"); assert(global->getInitializer()); // Note that we might also be Failed. Finalized = true; if (!PlaceholderAddresses.empty()) { ReplacePlaceholders(CGM, global, PlaceholderAddresses) .replaceInInitializer(global->getInitializer()); PlaceholderAddresses.clear(); // satisfy } } ConstantEmitter::~ConstantEmitter() { assert((!InitializedNonAbstract || Finalized || Failed) && "not finalized after being initialized for non-abstract emission"); assert(PlaceholderAddresses.empty() && "unhandled placeholders"); } static QualType getNonMemoryType(CodeGenModule &CGM, QualType type) { if (auto AT = type->getAs()) { return CGM.getContext().getQualifiedType(AT->getValueType(), type.getQualifiers()); } return type; } llvm::Constant *ConstantEmitter::tryEmitPrivateForVarInit(const VarDecl &D) { d1209 3 a1211 1 QualType Ty = CGM.getContext().getBaseElementType(D.getType()); d1217 1 a1217 1 return CGM.EmitNullConstant(D.getType()); d1220 3 a1222 8 QualType destType = D.getType(); // Try to emit the initializer. Note that this can allow some things that // are not allowed by tryEmitPrivateForMemory alone. if (auto value = D.evaluateValue()) { return tryEmitPrivateForMemory(*value, destType); } d1230 1 a1230 1 if (destType->isReferenceType()) d1236 4 a1239 61 auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = ConstExprEmitter(*this).Visit(const_cast(E), nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant * ConstantEmitter::tryEmitAbstractForMemory(const Expr *E, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = tryEmitAbstract(E, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant * ConstantEmitter::tryEmitAbstractForMemory(const APValue &value, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = tryEmitAbstract(value, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant *ConstantEmitter::tryEmitPrivateForMemory(const Expr *E, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); llvm::Constant *C = tryEmitPrivate(E, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant *ConstantEmitter::tryEmitPrivateForMemory(const APValue &value, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = tryEmitPrivate(value, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant *ConstantEmitter::emitForMemory(CodeGenModule &CGM, llvm::Constant *C, QualType destType) { // For an _Atomic-qualified constant, we may need to add tail padding. if (auto AT = destType->getAs()) { QualType destValueType = AT->getValueType(); C = emitForMemory(CGM, C, destValueType); uint64_t innerSize = CGM.getContext().getTypeSize(destValueType); uint64_t outerSize = CGM.getContext().getTypeSize(destType); if (innerSize == outerSize) return C; assert(innerSize < outerSize && "emitted over-large constant for atomic"); llvm::Constant *elts[] = { C, llvm::ConstantAggregateZero::get( llvm::ArrayType::get(CGM.Int8Ty, (outerSize - innerSize) / 8)) }; return llvm::ConstantStruct::getAnon(elts); } // Zero-extend bool. if (C->getType()->isIntegerTy(1)) { llvm::Type *boolTy = CGM.getTypes().ConvertTypeForMem(destType); return llvm::ConstantExpr::getZExt(C, boolTy); a1240 1 d1244 3 a1246 2 llvm::Constant *ConstantEmitter::tryEmitPrivate(const Expr *E, QualType destType) { d1251 2 a1252 2 if (destType->isReferenceType()) Success = E->EvaluateAsLValue(Result, CGM.getContext()); d1254 1 a1254 1 Success = E->EvaluateAsRValue(Result, CGM.getContext()); d1256 1 a1256 1 llvm::Constant *C; d1258 1 a1258 1 C = tryEmitPrivate(Result.Val, destType); d1260 1 a1260 1 C = ConstExprEmitter(*this).Visit(const_cast(E), destType); d1262 4 d1273 20 a1292 73 namespace { /// A struct which can be used to peephole certain kinds of finalization /// that normally happen during l-value emission. struct ConstantLValue { llvm::Constant *Value; bool HasOffsetApplied; /*implicit*/ ConstantLValue(llvm::Constant *value, bool hasOffsetApplied = false) : Value(value), HasOffsetApplied(false) {} /*implicit*/ ConstantLValue(ConstantAddress address) : ConstantLValue(address.getPointer()) {} }; /// A helper class for emitting constant l-values. class ConstantLValueEmitter : public ConstStmtVisitor { CodeGenModule &CGM; ConstantEmitter &Emitter; const APValue &Value; QualType DestType; // Befriend StmtVisitorBase so that we don't have to expose Visit*. friend StmtVisitorBase; public: ConstantLValueEmitter(ConstantEmitter &emitter, const APValue &value, QualType destType) : CGM(emitter.CGM), Emitter(emitter), Value(value), DestType(destType) {} llvm::Constant *tryEmit(); private: llvm::Constant *tryEmitAbsolute(llvm::Type *destTy); ConstantLValue tryEmitBase(const APValue::LValueBase &base); ConstantLValue VisitStmt(const Stmt *S) { return nullptr; } ConstantLValue VisitCompoundLiteralExpr(const CompoundLiteralExpr *E); ConstantLValue VisitStringLiteral(const StringLiteral *E); ConstantLValue VisitObjCEncodeExpr(const ObjCEncodeExpr *E); ConstantLValue VisitObjCStringLiteral(const ObjCStringLiteral *E); ConstantLValue VisitPredefinedExpr(const PredefinedExpr *E); ConstantLValue VisitAddrLabelExpr(const AddrLabelExpr *E); ConstantLValue VisitCallExpr(const CallExpr *E); ConstantLValue VisitBlockExpr(const BlockExpr *E); ConstantLValue VisitCXXTypeidExpr(const CXXTypeidExpr *E); ConstantLValue VisitCXXUuidofExpr(const CXXUuidofExpr *E); ConstantLValue VisitMaterializeTemporaryExpr( const MaterializeTemporaryExpr *E); bool hasNonZeroOffset() const { return !Value.getLValueOffset().isZero(); } /// Return the value offset. llvm::Constant *getOffset() { return llvm::ConstantInt::get(CGM.Int64Ty, Value.getLValueOffset().getQuantity()); } /// Apply the value offset to the given constant. llvm::Constant *applyOffset(llvm::Constant *C) { if (!hasNonZeroOffset()) return C; llvm::Type *origPtrTy = C->getType(); unsigned AS = origPtrTy->getPointerAddressSpace(); llvm::Type *charPtrTy = CGM.Int8Ty->getPointerTo(AS); C = llvm::ConstantExpr::getBitCast(C, charPtrTy); C = llvm::ConstantExpr::getGetElementPtr(CGM.Int8Ty, C, getOffset()); C = llvm::ConstantExpr::getPointerCast(C, origPtrTy); return C; a1293 1 }; d1295 17 a1311 1 } d1313 1 a1313 2 llvm::Constant *ConstantLValueEmitter::tryEmit() { const APValue::LValueBase &base = Value.getLValueBase(); d1315 8 a1322 9 // Certain special array initializers are represented in APValue // as l-values referring to the base expression which generates the // array. This happens with e.g. string literals. These should // probably just get their own representation kind in APValue. if (DestType->isArrayType()) { assert(!hasNonZeroOffset() && "offset on array initializer"); auto expr = const_cast(base.get()); return ConstExprEmitter(Emitter).Visit(expr, DestType); } d1324 4 a1327 9 // Otherwise, the destination type should be a pointer or reference // type, but it might also be a cast thereof. // // FIXME: the chain of casts required should be reflected in the APValue. // We need this in order to correctly handle things like a ptrtoint of a // non-zero null pointer and addrspace casts that aren't trivially // represented in LLVM IR. auto destTy = CGM.getTypes().ConvertTypeForMem(DestType); assert(isa(destTy) || isa(destTy)); d1329 3 a1331 5 // If there's no base at all, this is a null or absolute pointer, // possibly cast back to an integer type. if (!base) { return tryEmitAbsolute(destTy); } d1333 12 a1344 2 // Otherwise, try to emit the base. ConstantLValue result = tryEmitBase(base); d1346 3 a1348 3 // If that failed, we're done. llvm::Constant *value = result.Value; if (!value) return nullptr; d1350 1 a1350 69 // Apply the offset if necessary and not already done. if (!result.HasOffsetApplied) { value = applyOffset(value); } // Convert to the appropriate type; this could be an lvalue for // an integer. FIXME: performAddrSpaceCast if (isa(destTy)) return llvm::ConstantExpr::getPointerCast(value, destTy); return llvm::ConstantExpr::getPtrToInt(value, destTy); } /// Try to emit an absolute l-value, such as a null pointer or an integer /// bitcast to pointer type. llvm::Constant * ConstantLValueEmitter::tryEmitAbsolute(llvm::Type *destTy) { auto offset = getOffset(); // If we're producing a pointer, this is easy. if (auto destPtrTy = cast(destTy)) { if (Value.isNullPointer()) { // FIXME: integer offsets from non-zero null pointers. return CGM.getNullPointer(destPtrTy, DestType); } // Convert the integer to a pointer-sized integer before converting it // to a pointer. // FIXME: signedness depends on the original integer type. auto intptrTy = CGM.getDataLayout().getIntPtrType(destPtrTy); llvm::Constant *C = offset; C = llvm::ConstantExpr::getIntegerCast(getOffset(), intptrTy, /*isSigned*/ false); C = llvm::ConstantExpr::getIntToPtr(C, destPtrTy); return C; } // Otherwise, we're basically returning an integer constant. // FIXME: this does the wrong thing with ptrtoint of a null pointer, // but since we don't know the original pointer type, there's not much // we can do about it. auto C = getOffset(); C = llvm::ConstantExpr::getIntegerCast(C, destTy, /*isSigned*/ false); return C; } ConstantLValue ConstantLValueEmitter::tryEmitBase(const APValue::LValueBase &base) { // Handle values. if (const ValueDecl *D = base.dyn_cast()) { if (D->hasAttr()) return CGM.GetWeakRefReference(D).getPointer(); if (auto FD = dyn_cast(D)) return CGM.GetAddrOfFunction(FD); if (auto VD = dyn_cast(D)) { // We can never refer to a variable with local storage. if (!VD->hasLocalStorage()) { if (VD->isFileVarDecl() || VD->hasExternalStorage()) return CGM.GetAddrOfGlobalVar(VD); if (VD->isLocalVarDecl()) { return CGM.getOrCreateStaticVarDecl( *VD, CGM.getLLVMLinkageVarDefinition(VD, /*isConstant=*/false)); } } a1351 66 return nullptr; } // Otherwise, it must be an expression. return Visit(base.get()); } ConstantLValue ConstantLValueEmitter::VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) { return tryEmitGlobalCompoundLiteral(CGM, Emitter.CGF, E); } ConstantLValue ConstantLValueEmitter::VisitStringLiteral(const StringLiteral *E) { return CGM.GetAddrOfConstantStringFromLiteral(E); } ConstantLValue ConstantLValueEmitter::VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { return CGM.GetAddrOfConstantStringFromObjCEncode(E); } ConstantLValue ConstantLValueEmitter::VisitObjCStringLiteral(const ObjCStringLiteral *E) { auto C = CGM.getObjCRuntime().GenerateConstantString(E->getString()); return C.getElementBitCast(CGM.getTypes().ConvertTypeForMem(E->getType())); } ConstantLValue ConstantLValueEmitter::VisitPredefinedExpr(const PredefinedExpr *E) { if (auto CGF = Emitter.CGF) { LValue Res = CGF->EmitPredefinedLValue(E); return cast(Res.getAddress()); } auto kind = E->getIdentType(); if (kind == PredefinedExpr::PrettyFunction) { return CGM.GetAddrOfConstantCString("top level", ".tmp"); } return CGM.GetAddrOfConstantCString("", ".tmp"); } ConstantLValue ConstantLValueEmitter::VisitAddrLabelExpr(const AddrLabelExpr *E) { assert(Emitter.CGF && "Invalid address of label expression outside function"); llvm::Constant *Ptr = Emitter.CGF->GetAddrOfLabel(E->getLabel()); Ptr = llvm::ConstantExpr::getBitCast(Ptr, CGM.getTypes().ConvertType(E->getType())); return Ptr; } ConstantLValue ConstantLValueEmitter::VisitCallExpr(const CallExpr *E) { unsigned builtin = E->getBuiltinCallee(); if (builtin != Builtin::BI__builtin___CFStringMakeConstantString && builtin != Builtin::BI__builtin___NSStringMakeConstantString) return nullptr; auto literal = cast(E->getArg(0)->IgnoreParenCasts()); if (builtin == Builtin::BI__builtin___NSStringMakeConstantString) { return CGM.getObjCRuntime().GenerateConstantString(literal); } else { // FIXME: need to deal with UCN conversion issues. return CGM.GetAddrOfConstantCFString(literal); a1352 46 } ConstantLValue ConstantLValueEmitter::VisitBlockExpr(const BlockExpr *E) { StringRef functionName; if (auto CGF = Emitter.CGF) functionName = CGF->CurFn->getName(); else functionName = "global"; return CGM.GetAddrOfGlobalBlock(E, functionName); } ConstantLValue ConstantLValueEmitter::VisitCXXTypeidExpr(const CXXTypeidExpr *E) { QualType T; if (E->isTypeOperand()) T = E->getTypeOperand(CGM.getContext()); else T = E->getExprOperand()->getType(); return CGM.GetAddrOfRTTIDescriptor(T); } ConstantLValue ConstantLValueEmitter::VisitCXXUuidofExpr(const CXXUuidofExpr *E) { return CGM.GetAddrOfUuidDescriptor(E); } ConstantLValue ConstantLValueEmitter::VisitMaterializeTemporaryExpr( const MaterializeTemporaryExpr *E) { assert(E->getStorageDuration() == SD_Static); SmallVector CommaLHSs; SmallVector Adjustments; const Expr *Inner = E->GetTemporaryExpr() ->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); return CGM.GetAddrOfGlobalTemporary(E, Inner); } llvm::Constant *ConstantEmitter::tryEmitPrivate(const APValue &Value, QualType DestType) { switch (Value.getKind()) { case APValue::Uninitialized: llvm_unreachable("Constant expressions should be initialized."); case APValue::LValue: return ConstantLValueEmitter(*this, Value, DestType).tryEmit(); d1354 1 a1354 1 return llvm::ConstantInt::get(CGM.getLLVMContext(), Value.getInt()); d1358 1 a1358 1 Complex[0] = llvm::ConstantInt::get(CGM.getLLVMContext(), d1360 1 a1360 1 Complex[1] = llvm::ConstantInt::get(CGM.getLLVMContext(), d1371 3 a1373 4 !CGM.getContext().getLangOpts().NativeHalfType && CGM.getContext().getTargetInfo().useFP16ConversionIntrinsics()) return llvm::ConstantInt::get(CGM.getLLVMContext(), Init.bitcastToAPInt()); d1375 1 a1375 1 return llvm::ConstantFP::get(CGM.getLLVMContext(), Init); d1380 1 a1380 1 Complex[0] = llvm::ConstantFP::get(CGM.getLLVMContext(), d1382 1 a1382 1 Complex[1] = llvm::ConstantFP::get(CGM.getLLVMContext(), d1397 1 a1397 1 Inits[I] = llvm::ConstantInt::get(CGM.getLLVMContext(), Elt.getInt()); d1399 1 a1399 1 Inits[I] = llvm::ConstantFP::get(CGM.getLLVMContext(), Elt.getFloat()); d1408 2 a1409 3 llvm::Constant *LHS = tryEmitPrivate(LHSExpr, LHSExpr->getType()); llvm::Constant *RHS = tryEmitPrivate(RHSExpr, RHSExpr->getType()); if (!LHS || !RHS) return nullptr; d1412 3 a1414 3 llvm::Type *ResultType = CGM.getTypes().ConvertType(DestType); LHS = llvm::ConstantExpr::getPtrToInt(LHS, CGM.IntPtrTy); RHS = llvm::ConstantExpr::getPtrToInt(RHS, CGM.IntPtrTy); d1424 1 a1424 1 return ConstStructBuilder::BuildStruct(*this, Value, DestType); d1426 1 a1426 2 const ConstantArrayType *CAT = CGM.getContext().getAsConstantArrayType(DestType); d1432 3 a1434 6 if (Value.hasArrayFiller()) { Filler = tryEmitAbstractForMemory(Value.getArrayFiller(), CAT->getElementType()); if (!Filler) return nullptr; } d1437 2 a1438 11 SmallVector Elts; if (Filler && Filler->isNullValue()) Elts.reserve(NumInitElts + 1); else Elts.reserve(NumElements); llvm::Type *CommonElementType = nullptr; for (unsigned I = 0; I < NumInitElts; ++I) { llvm::Constant *C = tryEmitPrivateForMemory( Value.getArrayInitializedElt(I), CAT->getElementType()); if (!C) return nullptr; d1440 16 d1463 13 a1475 2 return EmitArrayConstant(CGM, CAT, CommonElementType, NumElements, Elts, Filler); d1478 1 a1478 1 return CGM.getCXXABI().EmitMemberPointer(Value, DestType); d1483 12 d1510 1 a1510 1 return tryEmitGlobalCompoundLiteral(*this, nullptr, E); a1631 5 llvm::Constant *ConstantEmitter::emitNullForMemory(CodeGenModule &CGM, QualType T) { return emitForMemory(CGM, CGM.EmitNullConstant(T), T); } d1646 1 a1646 2 llvm::Constant *Element = ConstantEmitter::emitNullForMemory(*this, ElementTy); @ 1.1.1.8.4.2 log @Mostly merge changes from HEAD upto 20200411 @ text @@ 1.1.1.8.2.1 log @Sync with HEAD @ text @a18 1 #include "ConstantEmitter.h" d40 1 a40 1 ConstantEmitter &Emitter; d47 2 a48 2 static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, ConstExprEmitter *ExprEmitter, d50 4 a53 5 InitListExpr *Updater, QualType ValTy); static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, InitListExpr *ILE, QualType StructTy); static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, d57 2 a58 2 ConstStructBuilder(ConstantEmitter &emitter) : CGM(emitter.CGM), Emitter(emitter), Packed(false), d79 1 a79 1 bool Build(const APValue &Val, const RecordDecl *RD, bool IsPrimaryBase, d394 2 a395 2 EltInit = Emitter.tryEmitPrivateForMemory(ILE->getInit(ElementNo++), Field->getType()); d397 1 a397 1 EltInit = Emitter.emitNullForMemory(Field->getType()); d434 1 a434 1 bool ConstStructBuilder::Build(const APValue &Val, const RecordDecl *RD, d489 2 a490 3 Emitter.tryEmitPrivateForMemory(FieldValue, Field->getType()); if (!EltInit) return false; a500 2 return true; d562 3 a564 2 llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, ConstExprEmitter *ExprEmitter, d566 3 a568 4 InitListExpr *Updater, QualType ValTy) { ConstStructBuilder Builder(Emitter); if (!Builder.Build(ExprEmitter, Base, Updater)) d570 1 a570 1 return Builder.Finalize(ValTy); d573 4 a576 4 llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, InitListExpr *ILE, QualType ValTy) { ConstStructBuilder Builder(Emitter); d581 1 a581 1 return Builder.Finalize(ValTy); d584 2 a585 1 llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, d588 1 a588 1 ConstStructBuilder Builder(Emitter); d592 1 a592 2 if (!Builder.Build(Val, RD, false, CD, CharUnits::Zero())) return nullptr; a601 85 static ConstantAddress tryEmitGlobalCompoundLiteral(CodeGenModule &CGM, CodeGenFunction *CGF, const CompoundLiteralExpr *E) { CharUnits Align = CGM.getContext().getTypeAlignInChars(E->getType()); if (llvm::GlobalVariable *Addr = CGM.getAddrOfConstantCompoundLiteralIfEmitted(E)) return ConstantAddress(Addr, Align); LangAS addressSpace = E->getType().getAddressSpace(); ConstantEmitter emitter(CGM, CGF); llvm::Constant *C = emitter.tryEmitForInitializer(E->getInitializer(), addressSpace, E->getType()); if (!C) { assert(!E->isFileScope() && "file-scope compound literal did not have constant initializer!"); return ConstantAddress::invalid(); } auto GV = new llvm::GlobalVariable(CGM.getModule(), C->getType(), CGM.isTypeConstant(E->getType(), true), llvm::GlobalValue::InternalLinkage, C, ".compoundliteral", nullptr, llvm::GlobalVariable::NotThreadLocal, CGM.getContext().getTargetAddressSpace(addressSpace)); emitter.finalize(GV); GV->setAlignment(Align.getQuantity()); CGM.setAddrOfConstantCompoundLiteral(E, GV); return ConstantAddress(GV, Align); } static llvm::Constant * EmitArrayConstant(CodeGenModule &CGM, const ConstantArrayType *DestType, llvm::Type *CommonElementType, unsigned ArrayBound, SmallVectorImpl &Elements, llvm::Constant *Filler) { // Figure out how long the initial prefix of non-zero elements is. unsigned NonzeroLength = ArrayBound; if (Elements.size() < NonzeroLength && Filler->isNullValue()) NonzeroLength = Elements.size(); if (NonzeroLength == Elements.size()) { while (NonzeroLength > 0 && Elements[NonzeroLength - 1]->isNullValue()) --NonzeroLength; } if (NonzeroLength == 0) { return llvm::ConstantAggregateZero::get( CGM.getTypes().ConvertType(QualType(DestType, 0))); } // Add a zeroinitializer array filler if we have lots of trailing zeroes. unsigned TrailingZeroes = ArrayBound - NonzeroLength; if (TrailingZeroes >= 8) { assert(Elements.size() >= NonzeroLength && "missing initializer for non-zero element"); Elements.resize(NonzeroLength + 1); auto *FillerType = CommonElementType ? CommonElementType : CGM.getTypes().ConvertType(DestType->getElementType()); FillerType = llvm::ArrayType::get(FillerType, TrailingZeroes); Elements.back() = llvm::ConstantAggregateZero::get(FillerType); CommonElementType = nullptr; } else if (Elements.size() != ArrayBound) { // Otherwise pad to the right size with the filler if necessary. Elements.resize(ArrayBound, Filler); if (Filler->getType() != CommonElementType) CommonElementType = nullptr; } // If all elements have the same type, just emit an array constant. if (CommonElementType) return llvm::ConstantArray::get( llvm::ArrayType::get(CommonElementType, ArrayBound), Elements); // We have mixed types. Use a packed struct. llvm::SmallVector Types; Types.reserve(Elements.size()); for (llvm::Constant *Elt : Elements) Types.push_back(Elt->getType()); llvm::StructType *SType = llvm::StructType::get(CGM.getLLVMContext(), Types, true); return llvm::ConstantStruct::get(SType, Elements); } d607 1 a607 1 public StmtVisitor { d609 1 a609 1 ConstantEmitter &Emitter; d612 2 a613 2 ConstExprEmitter(ConstantEmitter &emitter) : CGM(emitter.CGM), Emitter(emitter), VMContext(CGM.getLLVMContext()) { d620 1 a620 1 llvm::Constant *VisitStmt(Stmt *S, QualType T) { d624 2 a625 2 llvm::Constant *VisitParenExpr(ParenExpr *PE, QualType T) { return Visit(PE->getSubExpr(), T); d629 2 a630 3 VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE, QualType T) { return Visit(PE->getReplacement(), T); d633 2 a634 3 llvm::Constant *VisitGenericSelectionExpr(GenericSelectionExpr *GE, QualType T) { return Visit(GE->getResultExpr(), T); d637 2 a638 2 llvm::Constant *VisitChooseExpr(ChooseExpr *CE, QualType T) { return Visit(CE->getChosenSubExpr(), T); d641 2 a642 2 llvm::Constant *VisitCompoundLiteralExpr(CompoundLiteralExpr *E, QualType T) { return Visit(E->getInitializer(), T); d645 1 a645 1 llvm::Constant *VisitCastExpr(CastExpr *E, QualType destType) { d647 1 a647 1 CGM.EmitExplicitCastExprType(ECE, Emitter.CGF); d649 4 a659 8 auto field = E->getTargetUnionField(); auto C = Emitter.tryEmitPrivateForMemory(subExpr, field->getType()); if (!C) return nullptr; auto destTy = ConvertType(destType); if (C->getType() == destTy) return C; d661 1 a661 1 // and padded to the appropriate size. d667 1 a667 1 unsigned TotalSize = CGM.getDataLayout().getTypeAllocSize(destTy); d679 2 a680 1 llvm::StructType *STy = llvm::StructType::get(VMContext, Types, false); d684 2 a685 9 case CK_AddressSpaceConversion: { auto C = Emitter.tryEmitPrivate(subExpr, subExpr->getType()); if (!C) return nullptr; LangAS destAS = E->getType()->getPointeeType().getAddressSpace(); LangAS srcAS = subExpr->getType()->getPointeeType().getAddressSpace(); llvm::Type *destTy = ConvertType(E->getType()); return CGM.getTargetCodeGenInfo().performAddrSpaceCast(CGM, C, srcAS, destAS, destTy); } d692 1 a692 1 return Visit(subExpr, destType); d704 1 a704 3 case CK_BaseToDerivedMemberPointer: { auto C = Emitter.tryEmitPrivate(subExpr, subExpr->getType()); if (!C) return nullptr; a705 1 } d762 2 a763 2 llvm::Constant *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE, QualType T) { return Visit(DAE->getExpr(), T); d766 1 a766 1 llvm::Constant *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE, QualType T) { d769 1 a769 1 return Visit(DIE->getExpr(), T); d772 1 a772 1 llvm::Constant *VisitExprWithCleanups(ExprWithCleanups *E, QualType T) { d774 1 a774 1 return Visit(E->getSubExpr(), T); d778 2 a779 3 llvm::Constant *VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E, QualType T) { return Visit(E->GetTemporaryExpr(), T); d782 4 a785 3 llvm::Constant *EmitArrayInitialization(InitListExpr *ILE, QualType T) { auto *CAT = CGM.getContext().getAsConstantArrayType(ILE->getType()); assert(CAT && "can't emit array init for non-constant-bound array"); d787 1 a787 1 unsigned NumElements = CAT->getSize().getZExtValue(); d793 9 a801 1 QualType EltType = CAT->getElementType(); d803 3 a805 7 // Initialize remaining array elements. llvm::Constant *fillC = nullptr; if (Expr *filler = ILE->getArrayFiller()) { fillC = Emitter.tryEmitAbstractForMemory(filler, EltType); if (!fillC) return nullptr; } d808 2 a809 5 SmallVector Elts; if (fillC && fillC->isNullValue()) Elts.reserve(NumInitableElts + 1); else Elts.reserve(NumElements); d811 1 a811 1 llvm::Type *CommonElementType = nullptr; d814 1 a814 1 llvm::Constant *C = Emitter.tryEmitPrivateForMemory(Init, EltType); d817 1 a817 4 if (i == 0) CommonElementType = C->getType(); else if (C->getType() != CommonElementType) CommonElementType = nullptr; d821 15 a835 2 return EmitArrayConstant(CGM, CAT, CommonElementType, NumElements, Elts, fillC); d838 2 a839 2 llvm::Constant *EmitRecordInitialization(InitListExpr *ILE, QualType T) { return ConstStructBuilder::BuildStruct(Emitter, ILE, T); d842 2 a843 3 llvm::Constant *VisitImplicitValueInitExpr(ImplicitValueInitExpr* E, QualType T) { return CGM.EmitNullConstant(T); d846 1 a846 1 llvm::Constant *VisitInitListExpr(InitListExpr *ILE, QualType T) { d848 1 a848 1 return Visit(ILE->getInit(0), T); d851 1 a851 1 return EmitArrayInitialization(ILE, T); d854 1 a854 1 return EmitRecordInitialization(ILE, T); d860 5 a864 4 InitListExpr *Updater, QualType destType) { if (auto destAT = CGM.getContext().getAsArrayType(destType)) { llvm::ArrayType *AType = cast(ConvertType(destType)); d873 2 a874 3 QualType destElemType = destAT->getElementType(); if (auto DataArray = dyn_cast(Base)) d877 2 a878 1 else if (auto Array = dyn_cast(Base)) d887 1 a887 1 fillC = Emitter.tryEmitAbstractForMemory(filler, destElemType); d900 1 a900 1 Elts[i] = EmitDesignatedInitUpdater(Elts[i], ChildILE, destElemType); d902 1 a902 1 Elts[i] = Emitter.tryEmitPrivateForMemory(Init, destElemType); d922 3 a924 3 if (destType->isRecordType()) return ConstStructBuilder::BuildStruct(Emitter, this, dyn_cast(Base), Updater, destType); d929 4 a932 5 llvm::Constant *VisitDesignatedInitUpdateExpr(DesignatedInitUpdateExpr *E, QualType destType) { auto C = Visit(E->getBase(), destType); if (!C) return nullptr; return EmitDesignatedInitUpdater(C, E->getUpdater(), destType); d935 1 a935 1 llvm::Constant *VisitCXXConstructExpr(CXXConstructExpr *E, QualType Ty) { d939 2 d963 1 a963 1 return Visit(Arg, Ty); d969 1 a969 1 llvm::Constant *VisitStringLiteral(StringLiteral *E, QualType T) { d973 1 a973 1 llvm::Constant *VisitObjCEncodeExpr(ObjCEncodeExpr *E, QualType T) { d979 4 a982 1 const ConstantArrayType *CAT = CGM.getContext().getAsConstantArrayType(T); d990 2 a991 2 llvm::Constant *VisitUnaryExtension(const UnaryOperator *E, QualType T) { return Visit(E->getSubExpr(), T); d998 132 d1134 1 a1134 1 bool ConstStructBuilder::Build(ConstExprEmitter *ExprEmitter, d1182 1 a1182 2 EltInit = ExprEmitter->EmitDesignatedInitUpdater(EltInit, ChildILE, Field->getType()); d1184 1 a1184 1 EltInit = Emitter.tryEmitPrivateForMemory(Init, Field->getType()); d1203 2 a1204 267 llvm::Constant *ConstantEmitter::validateAndPopAbstract(llvm::Constant *C, AbstractState saved) { Abstract = saved.OldValue; assert(saved.OldPlaceholdersSize == PlaceholderAddresses.size() && "created a placeholder while doing an abstract emission?"); // No validation necessary for now. // No cleanup to do for now. return C; } llvm::Constant * ConstantEmitter::tryEmitAbstractForInitializer(const VarDecl &D) { auto state = pushAbstract(); auto C = tryEmitPrivateForVarInit(D); return validateAndPopAbstract(C, state); } llvm::Constant * ConstantEmitter::tryEmitAbstract(const Expr *E, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(E, destType); return validateAndPopAbstract(C, state); } llvm::Constant * ConstantEmitter::tryEmitAbstract(const APValue &value, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(value, destType); return validateAndPopAbstract(C, state); } llvm::Constant * ConstantEmitter::emitAbstract(const Expr *E, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(E, destType); C = validateAndPopAbstract(C, state); if (!C) { CGM.Error(E->getExprLoc(), "internal error: could not emit constant value \"abstractly\""); C = CGM.EmitNullConstant(destType); } return C; } llvm::Constant * ConstantEmitter::emitAbstract(SourceLocation loc, const APValue &value, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(value, destType); C = validateAndPopAbstract(C, state); if (!C) { CGM.Error(loc, "internal error: could not emit constant value \"abstractly\""); C = CGM.EmitNullConstant(destType); } return C; } llvm::Constant *ConstantEmitter::tryEmitForInitializer(const VarDecl &D) { initializeNonAbstract(D.getType().getAddressSpace()); return markIfFailed(tryEmitPrivateForVarInit(D)); } llvm::Constant *ConstantEmitter::tryEmitForInitializer(const Expr *E, LangAS destAddrSpace, QualType destType) { initializeNonAbstract(destAddrSpace); return markIfFailed(tryEmitPrivateForMemory(E, destType)); } llvm::Constant *ConstantEmitter::emitForInitializer(const APValue &value, LangAS destAddrSpace, QualType destType) { initializeNonAbstract(destAddrSpace); auto C = tryEmitPrivateForMemory(value, destType); assert(C && "couldn't emit constant value non-abstractly?"); return C; } llvm::GlobalValue *ConstantEmitter::getCurrentAddrPrivate() { assert(!Abstract && "cannot get current address for abstract constant"); // Make an obviously ill-formed global that should blow up compilation // if it survives. auto global = new llvm::GlobalVariable(CGM.getModule(), CGM.Int8Ty, true, llvm::GlobalValue::PrivateLinkage, /*init*/ nullptr, /*name*/ "", /*before*/ nullptr, llvm::GlobalVariable::NotThreadLocal, CGM.getContext().getTargetAddressSpace(DestAddressSpace)); PlaceholderAddresses.push_back(std::make_pair(nullptr, global)); return global; } void ConstantEmitter::registerCurrentAddrPrivate(llvm::Constant *signal, llvm::GlobalValue *placeholder) { assert(!PlaceholderAddresses.empty()); assert(PlaceholderAddresses.back().first == nullptr); assert(PlaceholderAddresses.back().second == placeholder); PlaceholderAddresses.back().first = signal; } namespace { struct ReplacePlaceholders { CodeGenModule &CGM; /// The base address of the global. llvm::Constant *Base; llvm::Type *BaseValueTy = nullptr; /// The placeholder addresses that were registered during emission. llvm::DenseMap PlaceholderAddresses; /// The locations of the placeholder signals. llvm::DenseMap Locations; /// The current index stack. We use a simple unsigned stack because /// we assume that placeholders will be relatively sparse in the /// initializer, but we cache the index values we find just in case. llvm::SmallVector Indices; llvm::SmallVector IndexValues; ReplacePlaceholders(CodeGenModule &CGM, llvm::Constant *base, ArrayRef> addresses) : CGM(CGM), Base(base), PlaceholderAddresses(addresses.begin(), addresses.end()) { } void replaceInInitializer(llvm::Constant *init) { // Remember the type of the top-most initializer. BaseValueTy = init->getType(); // Initialize the stack. Indices.push_back(0); IndexValues.push_back(nullptr); // Recurse into the initializer. findLocations(init); // Check invariants. assert(IndexValues.size() == Indices.size() && "mismatch"); assert(Indices.size() == 1 && "didn't pop all indices"); // Do the replacement; this basically invalidates 'init'. assert(Locations.size() == PlaceholderAddresses.size() && "missed a placeholder?"); // We're iterating over a hashtable, so this would be a source of // non-determinism in compiler output *except* that we're just // messing around with llvm::Constant structures, which never itself // does anything that should be visible in compiler output. for (auto &entry : Locations) { assert(entry.first->getParent() == nullptr && "not a placeholder!"); entry.first->replaceAllUsesWith(entry.second); entry.first->eraseFromParent(); } } private: void findLocations(llvm::Constant *init) { // Recurse into aggregates. if (auto agg = dyn_cast(init)) { for (unsigned i = 0, e = agg->getNumOperands(); i != e; ++i) { Indices.push_back(i); IndexValues.push_back(nullptr); findLocations(agg->getOperand(i)); IndexValues.pop_back(); Indices.pop_back(); } return; } // Otherwise, check for registered constants. while (true) { auto it = PlaceholderAddresses.find(init); if (it != PlaceholderAddresses.end()) { setLocation(it->second); break; } // Look through bitcasts or other expressions. if (auto expr = dyn_cast(init)) { init = expr->getOperand(0); } else { break; } } } void setLocation(llvm::GlobalVariable *placeholder) { assert(Locations.find(placeholder) == Locations.end() && "already found location for placeholder!"); // Lazily fill in IndexValues with the values from Indices. // We do this in reverse because we should always have a strict // prefix of indices from the start. assert(Indices.size() == IndexValues.size()); for (size_t i = Indices.size() - 1; i != size_t(-1); --i) { if (IndexValues[i]) { #ifndef NDEBUG for (size_t j = 0; j != i + 1; ++j) { assert(IndexValues[j] && isa(IndexValues[j]) && cast(IndexValues[j])->getZExtValue() == Indices[j]); } #endif break; } IndexValues[i] = llvm::ConstantInt::get(CGM.Int32Ty, Indices[i]); } // Form a GEP and then bitcast to the placeholder type so that the // replacement will succeed. llvm::Constant *location = llvm::ConstantExpr::getInBoundsGetElementPtr(BaseValueTy, Base, IndexValues); location = llvm::ConstantExpr::getBitCast(location, placeholder->getType()); Locations.insert({placeholder, location}); } }; } void ConstantEmitter::finalize(llvm::GlobalVariable *global) { assert(InitializedNonAbstract && "finalizing emitter that was used for abstract emission?"); assert(!Finalized && "finalizing emitter multiple times"); assert(global->getInitializer()); // Note that we might also be Failed. Finalized = true; if (!PlaceholderAddresses.empty()) { ReplacePlaceholders(CGM, global, PlaceholderAddresses) .replaceInInitializer(global->getInitializer()); PlaceholderAddresses.clear(); // satisfy } } ConstantEmitter::~ConstantEmitter() { assert((!InitializedNonAbstract || Finalized || Failed) && "not finalized after being initialized for non-abstract emission"); assert(PlaceholderAddresses.empty() && "unhandled placeholders"); } static QualType getNonMemoryType(CodeGenModule &CGM, QualType type) { if (auto AT = type->getAs()) { return CGM.getContext().getQualifiedType(AT->getValueType(), type.getQualifiers()); } return type; } llvm::Constant *ConstantEmitter::tryEmitPrivateForVarInit(const VarDecl &D) { d1209 3 a1211 1 QualType Ty = CGM.getContext().getBaseElementType(D.getType()); d1217 1 a1217 1 return CGM.EmitNullConstant(D.getType()); d1220 3 a1222 8 QualType destType = D.getType(); // Try to emit the initializer. Note that this can allow some things that // are not allowed by tryEmitPrivateForMemory alone. if (auto value = D.evaluateValue()) { return tryEmitPrivateForMemory(*value, destType); } d1230 1 a1230 1 if (destType->isReferenceType()) d1236 4 a1239 61 auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = ConstExprEmitter(*this).Visit(const_cast(E), nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant * ConstantEmitter::tryEmitAbstractForMemory(const Expr *E, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = tryEmitAbstract(E, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant * ConstantEmitter::tryEmitAbstractForMemory(const APValue &value, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = tryEmitAbstract(value, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant *ConstantEmitter::tryEmitPrivateForMemory(const Expr *E, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); llvm::Constant *C = tryEmitPrivate(E, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant *ConstantEmitter::tryEmitPrivateForMemory(const APValue &value, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = tryEmitPrivate(value, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant *ConstantEmitter::emitForMemory(CodeGenModule &CGM, llvm::Constant *C, QualType destType) { // For an _Atomic-qualified constant, we may need to add tail padding. if (auto AT = destType->getAs()) { QualType destValueType = AT->getValueType(); C = emitForMemory(CGM, C, destValueType); uint64_t innerSize = CGM.getContext().getTypeSize(destValueType); uint64_t outerSize = CGM.getContext().getTypeSize(destType); if (innerSize == outerSize) return C; assert(innerSize < outerSize && "emitted over-large constant for atomic"); llvm::Constant *elts[] = { C, llvm::ConstantAggregateZero::get( llvm::ArrayType::get(CGM.Int8Ty, (outerSize - innerSize) / 8)) }; return llvm::ConstantStruct::getAnon(elts); } // Zero-extend bool. if (C->getType()->isIntegerTy(1)) { llvm::Type *boolTy = CGM.getTypes().ConvertTypeForMem(destType); return llvm::ConstantExpr::getZExt(C, boolTy); a1240 1 d1244 3 a1246 2 llvm::Constant *ConstantEmitter::tryEmitPrivate(const Expr *E, QualType destType) { d1251 2 a1252 2 if (destType->isReferenceType()) Success = E->EvaluateAsLValue(Result, CGM.getContext()); d1254 1 a1254 1 Success = E->EvaluateAsRValue(Result, CGM.getContext()); d1256 1 a1256 1 llvm::Constant *C; d1258 1 a1258 1 C = tryEmitPrivate(Result.Val, destType); d1260 1 a1260 1 C = ConstExprEmitter(*this).Visit(const_cast(E), destType); d1262 4 d1273 20 a1292 73 namespace { /// A struct which can be used to peephole certain kinds of finalization /// that normally happen during l-value emission. struct ConstantLValue { llvm::Constant *Value; bool HasOffsetApplied; /*implicit*/ ConstantLValue(llvm::Constant *value, bool hasOffsetApplied = false) : Value(value), HasOffsetApplied(false) {} /*implicit*/ ConstantLValue(ConstantAddress address) : ConstantLValue(address.getPointer()) {} }; /// A helper class for emitting constant l-values. class ConstantLValueEmitter : public ConstStmtVisitor { CodeGenModule &CGM; ConstantEmitter &Emitter; const APValue &Value; QualType DestType; // Befriend StmtVisitorBase so that we don't have to expose Visit*. friend StmtVisitorBase; public: ConstantLValueEmitter(ConstantEmitter &emitter, const APValue &value, QualType destType) : CGM(emitter.CGM), Emitter(emitter), Value(value), DestType(destType) {} llvm::Constant *tryEmit(); private: llvm::Constant *tryEmitAbsolute(llvm::Type *destTy); ConstantLValue tryEmitBase(const APValue::LValueBase &base); ConstantLValue VisitStmt(const Stmt *S) { return nullptr; } ConstantLValue VisitCompoundLiteralExpr(const CompoundLiteralExpr *E); ConstantLValue VisitStringLiteral(const StringLiteral *E); ConstantLValue VisitObjCEncodeExpr(const ObjCEncodeExpr *E); ConstantLValue VisitObjCStringLiteral(const ObjCStringLiteral *E); ConstantLValue VisitPredefinedExpr(const PredefinedExpr *E); ConstantLValue VisitAddrLabelExpr(const AddrLabelExpr *E); ConstantLValue VisitCallExpr(const CallExpr *E); ConstantLValue VisitBlockExpr(const BlockExpr *E); ConstantLValue VisitCXXTypeidExpr(const CXXTypeidExpr *E); ConstantLValue VisitCXXUuidofExpr(const CXXUuidofExpr *E); ConstantLValue VisitMaterializeTemporaryExpr( const MaterializeTemporaryExpr *E); bool hasNonZeroOffset() const { return !Value.getLValueOffset().isZero(); } /// Return the value offset. llvm::Constant *getOffset() { return llvm::ConstantInt::get(CGM.Int64Ty, Value.getLValueOffset().getQuantity()); } /// Apply the value offset to the given constant. llvm::Constant *applyOffset(llvm::Constant *C) { if (!hasNonZeroOffset()) return C; llvm::Type *origPtrTy = C->getType(); unsigned AS = origPtrTy->getPointerAddressSpace(); llvm::Type *charPtrTy = CGM.Int8Ty->getPointerTo(AS); C = llvm::ConstantExpr::getBitCast(C, charPtrTy); C = llvm::ConstantExpr::getGetElementPtr(CGM.Int8Ty, C, getOffset()); C = llvm::ConstantExpr::getPointerCast(C, origPtrTy); return C; a1293 1 }; d1295 17 a1311 1 } d1313 1 a1313 2 llvm::Constant *ConstantLValueEmitter::tryEmit() { const APValue::LValueBase &base = Value.getLValueBase(); d1315 8 a1322 9 // Certain special array initializers are represented in APValue // as l-values referring to the base expression which generates the // array. This happens with e.g. string literals. These should // probably just get their own representation kind in APValue. if (DestType->isArrayType()) { assert(!hasNonZeroOffset() && "offset on array initializer"); auto expr = const_cast(base.get()); return ConstExprEmitter(Emitter).Visit(expr, DestType); } d1324 4 a1327 9 // Otherwise, the destination type should be a pointer or reference // type, but it might also be a cast thereof. // // FIXME: the chain of casts required should be reflected in the APValue. // We need this in order to correctly handle things like a ptrtoint of a // non-zero null pointer and addrspace casts that aren't trivially // represented in LLVM IR. auto destTy = CGM.getTypes().ConvertTypeForMem(DestType); assert(isa(destTy) || isa(destTy)); d1329 3 a1331 5 // If there's no base at all, this is a null or absolute pointer, // possibly cast back to an integer type. if (!base) { return tryEmitAbsolute(destTy); } d1333 12 a1344 2 // Otherwise, try to emit the base. ConstantLValue result = tryEmitBase(base); d1346 3 a1348 3 // If that failed, we're done. llvm::Constant *value = result.Value; if (!value) return nullptr; d1350 1 a1350 69 // Apply the offset if necessary and not already done. if (!result.HasOffsetApplied) { value = applyOffset(value); } // Convert to the appropriate type; this could be an lvalue for // an integer. FIXME: performAddrSpaceCast if (isa(destTy)) return llvm::ConstantExpr::getPointerCast(value, destTy); return llvm::ConstantExpr::getPtrToInt(value, destTy); } /// Try to emit an absolute l-value, such as a null pointer or an integer /// bitcast to pointer type. llvm::Constant * ConstantLValueEmitter::tryEmitAbsolute(llvm::Type *destTy) { auto offset = getOffset(); // If we're producing a pointer, this is easy. if (auto destPtrTy = cast(destTy)) { if (Value.isNullPointer()) { // FIXME: integer offsets from non-zero null pointers. return CGM.getNullPointer(destPtrTy, DestType); } // Convert the integer to a pointer-sized integer before converting it // to a pointer. // FIXME: signedness depends on the original integer type. auto intptrTy = CGM.getDataLayout().getIntPtrType(destPtrTy); llvm::Constant *C = offset; C = llvm::ConstantExpr::getIntegerCast(getOffset(), intptrTy, /*isSigned*/ false); C = llvm::ConstantExpr::getIntToPtr(C, destPtrTy); return C; } // Otherwise, we're basically returning an integer constant. // FIXME: this does the wrong thing with ptrtoint of a null pointer, // but since we don't know the original pointer type, there's not much // we can do about it. auto C = getOffset(); C = llvm::ConstantExpr::getIntegerCast(C, destTy, /*isSigned*/ false); return C; } ConstantLValue ConstantLValueEmitter::tryEmitBase(const APValue::LValueBase &base) { // Handle values. if (const ValueDecl *D = base.dyn_cast()) { if (D->hasAttr()) return CGM.GetWeakRefReference(D).getPointer(); if (auto FD = dyn_cast(D)) return CGM.GetAddrOfFunction(FD); if (auto VD = dyn_cast(D)) { // We can never refer to a variable with local storage. if (!VD->hasLocalStorage()) { if (VD->isFileVarDecl() || VD->hasExternalStorage()) return CGM.GetAddrOfGlobalVar(VD); if (VD->isLocalVarDecl()) { return CGM.getOrCreateStaticVarDecl( *VD, CGM.getLLVMLinkageVarDefinition(VD, /*isConstant=*/false)); } } a1351 66 return nullptr; } // Otherwise, it must be an expression. return Visit(base.get()); } ConstantLValue ConstantLValueEmitter::VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) { return tryEmitGlobalCompoundLiteral(CGM, Emitter.CGF, E); } ConstantLValue ConstantLValueEmitter::VisitStringLiteral(const StringLiteral *E) { return CGM.GetAddrOfConstantStringFromLiteral(E); } ConstantLValue ConstantLValueEmitter::VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { return CGM.GetAddrOfConstantStringFromObjCEncode(E); } ConstantLValue ConstantLValueEmitter::VisitObjCStringLiteral(const ObjCStringLiteral *E) { auto C = CGM.getObjCRuntime().GenerateConstantString(E->getString()); return C.getElementBitCast(CGM.getTypes().ConvertTypeForMem(E->getType())); } ConstantLValue ConstantLValueEmitter::VisitPredefinedExpr(const PredefinedExpr *E) { if (auto CGF = Emitter.CGF) { LValue Res = CGF->EmitPredefinedLValue(E); return cast(Res.getAddress()); } auto kind = E->getIdentType(); if (kind == PredefinedExpr::PrettyFunction) { return CGM.GetAddrOfConstantCString("top level", ".tmp"); } return CGM.GetAddrOfConstantCString("", ".tmp"); } ConstantLValue ConstantLValueEmitter::VisitAddrLabelExpr(const AddrLabelExpr *E) { assert(Emitter.CGF && "Invalid address of label expression outside function"); llvm::Constant *Ptr = Emitter.CGF->GetAddrOfLabel(E->getLabel()); Ptr = llvm::ConstantExpr::getBitCast(Ptr, CGM.getTypes().ConvertType(E->getType())); return Ptr; } ConstantLValue ConstantLValueEmitter::VisitCallExpr(const CallExpr *E) { unsigned builtin = E->getBuiltinCallee(); if (builtin != Builtin::BI__builtin___CFStringMakeConstantString && builtin != Builtin::BI__builtin___NSStringMakeConstantString) return nullptr; auto literal = cast(E->getArg(0)->IgnoreParenCasts()); if (builtin == Builtin::BI__builtin___NSStringMakeConstantString) { return CGM.getObjCRuntime().GenerateConstantString(literal); } else { // FIXME: need to deal with UCN conversion issues. return CGM.GetAddrOfConstantCFString(literal); a1352 46 } ConstantLValue ConstantLValueEmitter::VisitBlockExpr(const BlockExpr *E) { StringRef functionName; if (auto CGF = Emitter.CGF) functionName = CGF->CurFn->getName(); else functionName = "global"; return CGM.GetAddrOfGlobalBlock(E, functionName); } ConstantLValue ConstantLValueEmitter::VisitCXXTypeidExpr(const CXXTypeidExpr *E) { QualType T; if (E->isTypeOperand()) T = E->getTypeOperand(CGM.getContext()); else T = E->getExprOperand()->getType(); return CGM.GetAddrOfRTTIDescriptor(T); } ConstantLValue ConstantLValueEmitter::VisitCXXUuidofExpr(const CXXUuidofExpr *E) { return CGM.GetAddrOfUuidDescriptor(E); } ConstantLValue ConstantLValueEmitter::VisitMaterializeTemporaryExpr( const MaterializeTemporaryExpr *E) { assert(E->getStorageDuration() == SD_Static); SmallVector CommaLHSs; SmallVector Adjustments; const Expr *Inner = E->GetTemporaryExpr() ->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); return CGM.GetAddrOfGlobalTemporary(E, Inner); } llvm::Constant *ConstantEmitter::tryEmitPrivate(const APValue &Value, QualType DestType) { switch (Value.getKind()) { case APValue::Uninitialized: llvm_unreachable("Constant expressions should be initialized."); case APValue::LValue: return ConstantLValueEmitter(*this, Value, DestType).tryEmit(); d1354 1 a1354 1 return llvm::ConstantInt::get(CGM.getLLVMContext(), Value.getInt()); d1358 1 a1358 1 Complex[0] = llvm::ConstantInt::get(CGM.getLLVMContext(), d1360 1 a1360 1 Complex[1] = llvm::ConstantInt::get(CGM.getLLVMContext(), d1371 3 a1373 4 !CGM.getContext().getLangOpts().NativeHalfType && CGM.getContext().getTargetInfo().useFP16ConversionIntrinsics()) return llvm::ConstantInt::get(CGM.getLLVMContext(), Init.bitcastToAPInt()); d1375 1 a1375 1 return llvm::ConstantFP::get(CGM.getLLVMContext(), Init); d1380 1 a1380 1 Complex[0] = llvm::ConstantFP::get(CGM.getLLVMContext(), d1382 1 a1382 1 Complex[1] = llvm::ConstantFP::get(CGM.getLLVMContext(), d1397 1 a1397 1 Inits[I] = llvm::ConstantInt::get(CGM.getLLVMContext(), Elt.getInt()); d1399 1 a1399 1 Inits[I] = llvm::ConstantFP::get(CGM.getLLVMContext(), Elt.getFloat()); d1408 2 a1409 3 llvm::Constant *LHS = tryEmitPrivate(LHSExpr, LHSExpr->getType()); llvm::Constant *RHS = tryEmitPrivate(RHSExpr, RHSExpr->getType()); if (!LHS || !RHS) return nullptr; d1412 3 a1414 3 llvm::Type *ResultType = CGM.getTypes().ConvertType(DestType); LHS = llvm::ConstantExpr::getPtrToInt(LHS, CGM.IntPtrTy); RHS = llvm::ConstantExpr::getPtrToInt(RHS, CGM.IntPtrTy); d1424 1 a1424 1 return ConstStructBuilder::BuildStruct(*this, Value, DestType); d1426 1 a1426 2 const ConstantArrayType *CAT = CGM.getContext().getAsConstantArrayType(DestType); d1432 3 a1434 6 if (Value.hasArrayFiller()) { Filler = tryEmitAbstractForMemory(Value.getArrayFiller(), CAT->getElementType()); if (!Filler) return nullptr; } d1437 2 a1438 11 SmallVector Elts; if (Filler && Filler->isNullValue()) Elts.reserve(NumInitElts + 1); else Elts.reserve(NumElements); llvm::Type *CommonElementType = nullptr; for (unsigned I = 0; I < NumInitElts; ++I) { llvm::Constant *C = tryEmitPrivateForMemory( Value.getArrayInitializedElt(I), CAT->getElementType()); if (!C) return nullptr; d1440 16 d1463 13 a1475 2 return EmitArrayConstant(CGM, CAT, CommonElementType, NumElements, Elts, Filler); d1478 1 a1478 1 return CGM.getCXXABI().EmitMemberPointer(Value, DestType); d1483 12 d1510 1 a1510 1 return tryEmitGlobalCompoundLiteral(*this, nullptr, E); a1631 5 llvm::Constant *ConstantEmitter::emitNullForMemory(CodeGenModule &CGM, QualType T) { return emitForMemory(CGM, CGM.EmitNullConstant(T), T); } d1646 1 a1646 2 llvm::Constant *Element = ConstantEmitter::emitNullForMemory(*this, ElementTy); @ 1.1.1.9 log @Import clang r337282 from trunk @ text @a18 1 #include "ConstantEmitter.h" d40 1 a40 1 ConstantEmitter &Emitter; d47 2 a48 2 static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, ConstExprEmitter *ExprEmitter, d50 4 a53 5 InitListExpr *Updater, QualType ValTy); static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, InitListExpr *ILE, QualType StructTy); static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, d57 2 a58 2 ConstStructBuilder(ConstantEmitter &emitter) : CGM(emitter.CGM), Emitter(emitter), Packed(false), d79 1 a79 1 bool Build(const APValue &Val, const RecordDecl *RD, bool IsPrimaryBase, d394 2 a395 2 EltInit = Emitter.tryEmitPrivateForMemory(ILE->getInit(ElementNo++), Field->getType()); d397 1 a397 1 EltInit = Emitter.emitNullForMemory(Field->getType()); d434 1 a434 1 bool ConstStructBuilder::Build(const APValue &Val, const RecordDecl *RD, d489 2 a490 3 Emitter.tryEmitPrivateForMemory(FieldValue, Field->getType()); if (!EltInit) return false; a500 2 return true; d562 3 a564 2 llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, ConstExprEmitter *ExprEmitter, d566 3 a568 4 InitListExpr *Updater, QualType ValTy) { ConstStructBuilder Builder(Emitter); if (!Builder.Build(ExprEmitter, Base, Updater)) d570 1 a570 1 return Builder.Finalize(ValTy); d573 4 a576 4 llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, InitListExpr *ILE, QualType ValTy) { ConstStructBuilder Builder(Emitter); d581 1 a581 1 return Builder.Finalize(ValTy); d584 2 a585 1 llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, d588 1 a588 1 ConstStructBuilder Builder(Emitter); d592 1 a592 2 if (!Builder.Build(Val, RD, false, CD, CharUnits::Zero())) return nullptr; a601 85 static ConstantAddress tryEmitGlobalCompoundLiteral(CodeGenModule &CGM, CodeGenFunction *CGF, const CompoundLiteralExpr *E) { CharUnits Align = CGM.getContext().getTypeAlignInChars(E->getType()); if (llvm::GlobalVariable *Addr = CGM.getAddrOfConstantCompoundLiteralIfEmitted(E)) return ConstantAddress(Addr, Align); LangAS addressSpace = E->getType().getAddressSpace(); ConstantEmitter emitter(CGM, CGF); llvm::Constant *C = emitter.tryEmitForInitializer(E->getInitializer(), addressSpace, E->getType()); if (!C) { assert(!E->isFileScope() && "file-scope compound literal did not have constant initializer!"); return ConstantAddress::invalid(); } auto GV = new llvm::GlobalVariable(CGM.getModule(), C->getType(), CGM.isTypeConstant(E->getType(), true), llvm::GlobalValue::InternalLinkage, C, ".compoundliteral", nullptr, llvm::GlobalVariable::NotThreadLocal, CGM.getContext().getTargetAddressSpace(addressSpace)); emitter.finalize(GV); GV->setAlignment(Align.getQuantity()); CGM.setAddrOfConstantCompoundLiteral(E, GV); return ConstantAddress(GV, Align); } static llvm::Constant * EmitArrayConstant(CodeGenModule &CGM, const ConstantArrayType *DestType, llvm::Type *CommonElementType, unsigned ArrayBound, SmallVectorImpl &Elements, llvm::Constant *Filler) { // Figure out how long the initial prefix of non-zero elements is. unsigned NonzeroLength = ArrayBound; if (Elements.size() < NonzeroLength && Filler->isNullValue()) NonzeroLength = Elements.size(); if (NonzeroLength == Elements.size()) { while (NonzeroLength > 0 && Elements[NonzeroLength - 1]->isNullValue()) --NonzeroLength; } if (NonzeroLength == 0) { return llvm::ConstantAggregateZero::get( CGM.getTypes().ConvertType(QualType(DestType, 0))); } // Add a zeroinitializer array filler if we have lots of trailing zeroes. unsigned TrailingZeroes = ArrayBound - NonzeroLength; if (TrailingZeroes >= 8) { assert(Elements.size() >= NonzeroLength && "missing initializer for non-zero element"); Elements.resize(NonzeroLength + 1); auto *FillerType = CommonElementType ? CommonElementType : CGM.getTypes().ConvertType(DestType->getElementType()); FillerType = llvm::ArrayType::get(FillerType, TrailingZeroes); Elements.back() = llvm::ConstantAggregateZero::get(FillerType); CommonElementType = nullptr; } else if (Elements.size() != ArrayBound) { // Otherwise pad to the right size with the filler if necessary. Elements.resize(ArrayBound, Filler); if (Filler->getType() != CommonElementType) CommonElementType = nullptr; } // If all elements have the same type, just emit an array constant. if (CommonElementType) return llvm::ConstantArray::get( llvm::ArrayType::get(CommonElementType, ArrayBound), Elements); // We have mixed types. Use a packed struct. llvm::SmallVector Types; Types.reserve(Elements.size()); for (llvm::Constant *Elt : Elements) Types.push_back(Elt->getType()); llvm::StructType *SType = llvm::StructType::get(CGM.getLLVMContext(), Types, true); return llvm::ConstantStruct::get(SType, Elements); } d607 1 a607 1 public StmtVisitor { d609 1 a609 1 ConstantEmitter &Emitter; d612 2 a613 2 ConstExprEmitter(ConstantEmitter &emitter) : CGM(emitter.CGM), Emitter(emitter), VMContext(CGM.getLLVMContext()) { d620 1 a620 1 llvm::Constant *VisitStmt(Stmt *S, QualType T) { d624 2 a625 2 llvm::Constant *VisitParenExpr(ParenExpr *PE, QualType T) { return Visit(PE->getSubExpr(), T); d629 2 a630 3 VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE, QualType T) { return Visit(PE->getReplacement(), T); d633 2 a634 3 llvm::Constant *VisitGenericSelectionExpr(GenericSelectionExpr *GE, QualType T) { return Visit(GE->getResultExpr(), T); d637 2 a638 2 llvm::Constant *VisitChooseExpr(ChooseExpr *CE, QualType T) { return Visit(CE->getChosenSubExpr(), T); d641 2 a642 2 llvm::Constant *VisitCompoundLiteralExpr(CompoundLiteralExpr *E, QualType T) { return Visit(E->getInitializer(), T); d645 1 a645 1 llvm::Constant *VisitCastExpr(CastExpr *E, QualType destType) { d647 1 a647 1 CGM.EmitExplicitCastExprType(ECE, Emitter.CGF); d649 4 a659 8 auto field = E->getTargetUnionField(); auto C = Emitter.tryEmitPrivateForMemory(subExpr, field->getType()); if (!C) return nullptr; auto destTy = ConvertType(destType); if (C->getType() == destTy) return C; d661 1 a661 1 // and padded to the appropriate size. d667 1 a667 1 unsigned TotalSize = CGM.getDataLayout().getTypeAllocSize(destTy); d679 2 a680 1 llvm::StructType *STy = llvm::StructType::get(VMContext, Types, false); d684 2 a685 9 case CK_AddressSpaceConversion: { auto C = Emitter.tryEmitPrivate(subExpr, subExpr->getType()); if (!C) return nullptr; LangAS destAS = E->getType()->getPointeeType().getAddressSpace(); LangAS srcAS = subExpr->getType()->getPointeeType().getAddressSpace(); llvm::Type *destTy = ConvertType(E->getType()); return CGM.getTargetCodeGenInfo().performAddrSpaceCast(CGM, C, srcAS, destAS, destTy); } d692 1 a692 1 return Visit(subExpr, destType); d704 1 a704 3 case CK_BaseToDerivedMemberPointer: { auto C = Emitter.tryEmitPrivate(subExpr, subExpr->getType()); if (!C) return nullptr; a705 1 } d762 2 a763 2 llvm::Constant *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE, QualType T) { return Visit(DAE->getExpr(), T); d766 1 a766 1 llvm::Constant *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE, QualType T) { d769 1 a769 1 return Visit(DIE->getExpr(), T); d772 1 a772 1 llvm::Constant *VisitExprWithCleanups(ExprWithCleanups *E, QualType T) { d774 1 a774 1 return Visit(E->getSubExpr(), T); d778 2 a779 3 llvm::Constant *VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E, QualType T) { return Visit(E->GetTemporaryExpr(), T); d782 4 a785 3 llvm::Constant *EmitArrayInitialization(InitListExpr *ILE, QualType T) { auto *CAT = CGM.getContext().getAsConstantArrayType(ILE->getType()); assert(CAT && "can't emit array init for non-constant-bound array"); d787 1 a787 1 unsigned NumElements = CAT->getSize().getZExtValue(); d793 9 a801 1 QualType EltType = CAT->getElementType(); d803 3 a805 7 // Initialize remaining array elements. llvm::Constant *fillC = nullptr; if (Expr *filler = ILE->getArrayFiller()) { fillC = Emitter.tryEmitAbstractForMemory(filler, EltType); if (!fillC) return nullptr; } d808 2 a809 5 SmallVector Elts; if (fillC && fillC->isNullValue()) Elts.reserve(NumInitableElts + 1); else Elts.reserve(NumElements); d811 1 a811 1 llvm::Type *CommonElementType = nullptr; d814 1 a814 1 llvm::Constant *C = Emitter.tryEmitPrivateForMemory(Init, EltType); d817 1 a817 4 if (i == 0) CommonElementType = C->getType(); else if (C->getType() != CommonElementType) CommonElementType = nullptr; d821 15 a835 2 return EmitArrayConstant(CGM, CAT, CommonElementType, NumElements, Elts, fillC); d838 2 a839 2 llvm::Constant *EmitRecordInitialization(InitListExpr *ILE, QualType T) { return ConstStructBuilder::BuildStruct(Emitter, ILE, T); d842 2 a843 3 llvm::Constant *VisitImplicitValueInitExpr(ImplicitValueInitExpr* E, QualType T) { return CGM.EmitNullConstant(T); d846 1 a846 1 llvm::Constant *VisitInitListExpr(InitListExpr *ILE, QualType T) { d848 1 a848 1 return Visit(ILE->getInit(0), T); d851 1 a851 1 return EmitArrayInitialization(ILE, T); d854 1 a854 1 return EmitRecordInitialization(ILE, T); d860 5 a864 4 InitListExpr *Updater, QualType destType) { if (auto destAT = CGM.getContext().getAsArrayType(destType)) { llvm::ArrayType *AType = cast(ConvertType(destType)); d873 2 a874 3 QualType destElemType = destAT->getElementType(); if (auto DataArray = dyn_cast(Base)) d877 2 a878 1 else if (auto Array = dyn_cast(Base)) d887 1 a887 1 fillC = Emitter.tryEmitAbstractForMemory(filler, destElemType); d900 1 a900 1 Elts[i] = EmitDesignatedInitUpdater(Elts[i], ChildILE, destElemType); d902 1 a902 1 Elts[i] = Emitter.tryEmitPrivateForMemory(Init, destElemType); d922 3 a924 3 if (destType->isRecordType()) return ConstStructBuilder::BuildStruct(Emitter, this, dyn_cast(Base), Updater, destType); d929 4 a932 5 llvm::Constant *VisitDesignatedInitUpdateExpr(DesignatedInitUpdateExpr *E, QualType destType) { auto C = Visit(E->getBase(), destType); if (!C) return nullptr; return EmitDesignatedInitUpdater(C, E->getUpdater(), destType); d935 1 a935 1 llvm::Constant *VisitCXXConstructExpr(CXXConstructExpr *E, QualType Ty) { d939 2 d963 1 a963 1 return Visit(Arg, Ty); d969 1 a969 1 llvm::Constant *VisitStringLiteral(StringLiteral *E, QualType T) { d973 1 a973 1 llvm::Constant *VisitObjCEncodeExpr(ObjCEncodeExpr *E, QualType T) { d979 4 a982 1 const ConstantArrayType *CAT = CGM.getContext().getAsConstantArrayType(T); d990 2 a991 2 llvm::Constant *VisitUnaryExtension(const UnaryOperator *E, QualType T) { return Visit(E->getSubExpr(), T); d998 132 d1134 1 a1134 1 bool ConstStructBuilder::Build(ConstExprEmitter *ExprEmitter, d1182 1 a1182 2 EltInit = ExprEmitter->EmitDesignatedInitUpdater(EltInit, ChildILE, Field->getType()); d1184 1 a1184 1 EltInit = Emitter.tryEmitPrivateForMemory(Init, Field->getType()); d1203 2 a1204 267 llvm::Constant *ConstantEmitter::validateAndPopAbstract(llvm::Constant *C, AbstractState saved) { Abstract = saved.OldValue; assert(saved.OldPlaceholdersSize == PlaceholderAddresses.size() && "created a placeholder while doing an abstract emission?"); // No validation necessary for now. // No cleanup to do for now. return C; } llvm::Constant * ConstantEmitter::tryEmitAbstractForInitializer(const VarDecl &D) { auto state = pushAbstract(); auto C = tryEmitPrivateForVarInit(D); return validateAndPopAbstract(C, state); } llvm::Constant * ConstantEmitter::tryEmitAbstract(const Expr *E, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(E, destType); return validateAndPopAbstract(C, state); } llvm::Constant * ConstantEmitter::tryEmitAbstract(const APValue &value, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(value, destType); return validateAndPopAbstract(C, state); } llvm::Constant * ConstantEmitter::emitAbstract(const Expr *E, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(E, destType); C = validateAndPopAbstract(C, state); if (!C) { CGM.Error(E->getExprLoc(), "internal error: could not emit constant value \"abstractly\""); C = CGM.EmitNullConstant(destType); } return C; } llvm::Constant * ConstantEmitter::emitAbstract(SourceLocation loc, const APValue &value, QualType destType) { auto state = pushAbstract(); auto C = tryEmitPrivate(value, destType); C = validateAndPopAbstract(C, state); if (!C) { CGM.Error(loc, "internal error: could not emit constant value \"abstractly\""); C = CGM.EmitNullConstant(destType); } return C; } llvm::Constant *ConstantEmitter::tryEmitForInitializer(const VarDecl &D) { initializeNonAbstract(D.getType().getAddressSpace()); return markIfFailed(tryEmitPrivateForVarInit(D)); } llvm::Constant *ConstantEmitter::tryEmitForInitializer(const Expr *E, LangAS destAddrSpace, QualType destType) { initializeNonAbstract(destAddrSpace); return markIfFailed(tryEmitPrivateForMemory(E, destType)); } llvm::Constant *ConstantEmitter::emitForInitializer(const APValue &value, LangAS destAddrSpace, QualType destType) { initializeNonAbstract(destAddrSpace); auto C = tryEmitPrivateForMemory(value, destType); assert(C && "couldn't emit constant value non-abstractly?"); return C; } llvm::GlobalValue *ConstantEmitter::getCurrentAddrPrivate() { assert(!Abstract && "cannot get current address for abstract constant"); // Make an obviously ill-formed global that should blow up compilation // if it survives. auto global = new llvm::GlobalVariable(CGM.getModule(), CGM.Int8Ty, true, llvm::GlobalValue::PrivateLinkage, /*init*/ nullptr, /*name*/ "", /*before*/ nullptr, llvm::GlobalVariable::NotThreadLocal, CGM.getContext().getTargetAddressSpace(DestAddressSpace)); PlaceholderAddresses.push_back(std::make_pair(nullptr, global)); return global; } void ConstantEmitter::registerCurrentAddrPrivate(llvm::Constant *signal, llvm::GlobalValue *placeholder) { assert(!PlaceholderAddresses.empty()); assert(PlaceholderAddresses.back().first == nullptr); assert(PlaceholderAddresses.back().second == placeholder); PlaceholderAddresses.back().first = signal; } namespace { struct ReplacePlaceholders { CodeGenModule &CGM; /// The base address of the global. llvm::Constant *Base; llvm::Type *BaseValueTy = nullptr; /// The placeholder addresses that were registered during emission. llvm::DenseMap PlaceholderAddresses; /// The locations of the placeholder signals. llvm::DenseMap Locations; /// The current index stack. We use a simple unsigned stack because /// we assume that placeholders will be relatively sparse in the /// initializer, but we cache the index values we find just in case. llvm::SmallVector Indices; llvm::SmallVector IndexValues; ReplacePlaceholders(CodeGenModule &CGM, llvm::Constant *base, ArrayRef> addresses) : CGM(CGM), Base(base), PlaceholderAddresses(addresses.begin(), addresses.end()) { } void replaceInInitializer(llvm::Constant *init) { // Remember the type of the top-most initializer. BaseValueTy = init->getType(); // Initialize the stack. Indices.push_back(0); IndexValues.push_back(nullptr); // Recurse into the initializer. findLocations(init); // Check invariants. assert(IndexValues.size() == Indices.size() && "mismatch"); assert(Indices.size() == 1 && "didn't pop all indices"); // Do the replacement; this basically invalidates 'init'. assert(Locations.size() == PlaceholderAddresses.size() && "missed a placeholder?"); // We're iterating over a hashtable, so this would be a source of // non-determinism in compiler output *except* that we're just // messing around with llvm::Constant structures, which never itself // does anything that should be visible in compiler output. for (auto &entry : Locations) { assert(entry.first->getParent() == nullptr && "not a placeholder!"); entry.first->replaceAllUsesWith(entry.second); entry.first->eraseFromParent(); } } private: void findLocations(llvm::Constant *init) { // Recurse into aggregates. if (auto agg = dyn_cast(init)) { for (unsigned i = 0, e = agg->getNumOperands(); i != e; ++i) { Indices.push_back(i); IndexValues.push_back(nullptr); findLocations(agg->getOperand(i)); IndexValues.pop_back(); Indices.pop_back(); } return; } // Otherwise, check for registered constants. while (true) { auto it = PlaceholderAddresses.find(init); if (it != PlaceholderAddresses.end()) { setLocation(it->second); break; } // Look through bitcasts or other expressions. if (auto expr = dyn_cast(init)) { init = expr->getOperand(0); } else { break; } } } void setLocation(llvm::GlobalVariable *placeholder) { assert(Locations.find(placeholder) == Locations.end() && "already found location for placeholder!"); // Lazily fill in IndexValues with the values from Indices. // We do this in reverse because we should always have a strict // prefix of indices from the start. assert(Indices.size() == IndexValues.size()); for (size_t i = Indices.size() - 1; i != size_t(-1); --i) { if (IndexValues[i]) { #ifndef NDEBUG for (size_t j = 0; j != i + 1; ++j) { assert(IndexValues[j] && isa(IndexValues[j]) && cast(IndexValues[j])->getZExtValue() == Indices[j]); } #endif break; } IndexValues[i] = llvm::ConstantInt::get(CGM.Int32Ty, Indices[i]); } // Form a GEP and then bitcast to the placeholder type so that the // replacement will succeed. llvm::Constant *location = llvm::ConstantExpr::getInBoundsGetElementPtr(BaseValueTy, Base, IndexValues); location = llvm::ConstantExpr::getBitCast(location, placeholder->getType()); Locations.insert({placeholder, location}); } }; } void ConstantEmitter::finalize(llvm::GlobalVariable *global) { assert(InitializedNonAbstract && "finalizing emitter that was used for abstract emission?"); assert(!Finalized && "finalizing emitter multiple times"); assert(global->getInitializer()); // Note that we might also be Failed. Finalized = true; if (!PlaceholderAddresses.empty()) { ReplacePlaceholders(CGM, global, PlaceholderAddresses) .replaceInInitializer(global->getInitializer()); PlaceholderAddresses.clear(); // satisfy } } ConstantEmitter::~ConstantEmitter() { assert((!InitializedNonAbstract || Finalized || Failed) && "not finalized after being initialized for non-abstract emission"); assert(PlaceholderAddresses.empty() && "unhandled placeholders"); } static QualType getNonMemoryType(CodeGenModule &CGM, QualType type) { if (auto AT = type->getAs()) { return CGM.getContext().getQualifiedType(AT->getValueType(), type.getQualifiers()); } return type; } llvm::Constant *ConstantEmitter::tryEmitPrivateForVarInit(const VarDecl &D) { d1209 3 a1211 1 QualType Ty = CGM.getContext().getBaseElementType(D.getType()); d1217 1 a1217 1 return CGM.EmitNullConstant(D.getType()); d1220 3 a1222 8 QualType destType = D.getType(); // Try to emit the initializer. Note that this can allow some things that // are not allowed by tryEmitPrivateForMemory alone. if (auto value = D.evaluateValue()) { return tryEmitPrivateForMemory(*value, destType); } d1230 1 a1230 1 if (destType->isReferenceType()) d1236 4 a1239 61 auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = ConstExprEmitter(*this).Visit(const_cast(E), nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant * ConstantEmitter::tryEmitAbstractForMemory(const Expr *E, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = tryEmitAbstract(E, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant * ConstantEmitter::tryEmitAbstractForMemory(const APValue &value, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = tryEmitAbstract(value, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant *ConstantEmitter::tryEmitPrivateForMemory(const Expr *E, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); llvm::Constant *C = tryEmitPrivate(E, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant *ConstantEmitter::tryEmitPrivateForMemory(const APValue &value, QualType destType) { auto nonMemoryDestType = getNonMemoryType(CGM, destType); auto C = tryEmitPrivate(value, nonMemoryDestType); return (C ? emitForMemory(C, destType) : nullptr); } llvm::Constant *ConstantEmitter::emitForMemory(CodeGenModule &CGM, llvm::Constant *C, QualType destType) { // For an _Atomic-qualified constant, we may need to add tail padding. if (auto AT = destType->getAs()) { QualType destValueType = AT->getValueType(); C = emitForMemory(CGM, C, destValueType); uint64_t innerSize = CGM.getContext().getTypeSize(destValueType); uint64_t outerSize = CGM.getContext().getTypeSize(destType); if (innerSize == outerSize) return C; assert(innerSize < outerSize && "emitted over-large constant for atomic"); llvm::Constant *elts[] = { C, llvm::ConstantAggregateZero::get( llvm::ArrayType::get(CGM.Int8Ty, (outerSize - innerSize) / 8)) }; return llvm::ConstantStruct::getAnon(elts); } // Zero-extend bool. if (C->getType()->isIntegerTy(1)) { llvm::Type *boolTy = CGM.getTypes().ConvertTypeForMem(destType); return llvm::ConstantExpr::getZExt(C, boolTy); a1240 1 d1244 3 a1246 2 llvm::Constant *ConstantEmitter::tryEmitPrivate(const Expr *E, QualType destType) { d1251 2 a1252 2 if (destType->isReferenceType()) Success = E->EvaluateAsLValue(Result, CGM.getContext()); d1254 1 a1254 1 Success = E->EvaluateAsRValue(Result, CGM.getContext()); d1256 1 a1256 1 llvm::Constant *C; d1258 1 a1258 1 C = tryEmitPrivate(Result.Val, destType); d1260 1 a1260 1 C = ConstExprEmitter(*this).Visit(const_cast(E), destType); d1262 4 d1273 20 a1292 73 namespace { /// A struct which can be used to peephole certain kinds of finalization /// that normally happen during l-value emission. struct ConstantLValue { llvm::Constant *Value; bool HasOffsetApplied; /*implicit*/ ConstantLValue(llvm::Constant *value, bool hasOffsetApplied = false) : Value(value), HasOffsetApplied(false) {} /*implicit*/ ConstantLValue(ConstantAddress address) : ConstantLValue(address.getPointer()) {} }; /// A helper class for emitting constant l-values. class ConstantLValueEmitter : public ConstStmtVisitor { CodeGenModule &CGM; ConstantEmitter &Emitter; const APValue &Value; QualType DestType; // Befriend StmtVisitorBase so that we don't have to expose Visit*. friend StmtVisitorBase; public: ConstantLValueEmitter(ConstantEmitter &emitter, const APValue &value, QualType destType) : CGM(emitter.CGM), Emitter(emitter), Value(value), DestType(destType) {} llvm::Constant *tryEmit(); private: llvm::Constant *tryEmitAbsolute(llvm::Type *destTy); ConstantLValue tryEmitBase(const APValue::LValueBase &base); ConstantLValue VisitStmt(const Stmt *S) { return nullptr; } ConstantLValue VisitCompoundLiteralExpr(const CompoundLiteralExpr *E); ConstantLValue VisitStringLiteral(const StringLiteral *E); ConstantLValue VisitObjCEncodeExpr(const ObjCEncodeExpr *E); ConstantLValue VisitObjCStringLiteral(const ObjCStringLiteral *E); ConstantLValue VisitPredefinedExpr(const PredefinedExpr *E); ConstantLValue VisitAddrLabelExpr(const AddrLabelExpr *E); ConstantLValue VisitCallExpr(const CallExpr *E); ConstantLValue VisitBlockExpr(const BlockExpr *E); ConstantLValue VisitCXXTypeidExpr(const CXXTypeidExpr *E); ConstantLValue VisitCXXUuidofExpr(const CXXUuidofExpr *E); ConstantLValue VisitMaterializeTemporaryExpr( const MaterializeTemporaryExpr *E); bool hasNonZeroOffset() const { return !Value.getLValueOffset().isZero(); } /// Return the value offset. llvm::Constant *getOffset() { return llvm::ConstantInt::get(CGM.Int64Ty, Value.getLValueOffset().getQuantity()); } /// Apply the value offset to the given constant. llvm::Constant *applyOffset(llvm::Constant *C) { if (!hasNonZeroOffset()) return C; llvm::Type *origPtrTy = C->getType(); unsigned AS = origPtrTy->getPointerAddressSpace(); llvm::Type *charPtrTy = CGM.Int8Ty->getPointerTo(AS); C = llvm::ConstantExpr::getBitCast(C, charPtrTy); C = llvm::ConstantExpr::getGetElementPtr(CGM.Int8Ty, C, getOffset()); C = llvm::ConstantExpr::getPointerCast(C, origPtrTy); return C; a1293 1 }; d1295 17 a1311 1 } d1313 1 a1313 2 llvm::Constant *ConstantLValueEmitter::tryEmit() { const APValue::LValueBase &base = Value.getLValueBase(); d1315 8 a1322 9 // Certain special array initializers are represented in APValue // as l-values referring to the base expression which generates the // array. This happens with e.g. string literals. These should // probably just get their own representation kind in APValue. if (DestType->isArrayType()) { assert(!hasNonZeroOffset() && "offset on array initializer"); auto expr = const_cast(base.get()); return ConstExprEmitter(Emitter).Visit(expr, DestType); } d1324 4 a1327 9 // Otherwise, the destination type should be a pointer or reference // type, but it might also be a cast thereof. // // FIXME: the chain of casts required should be reflected in the APValue. // We need this in order to correctly handle things like a ptrtoint of a // non-zero null pointer and addrspace casts that aren't trivially // represented in LLVM IR. auto destTy = CGM.getTypes().ConvertTypeForMem(DestType); assert(isa(destTy) || isa(destTy)); d1329 3 a1331 5 // If there's no base at all, this is a null or absolute pointer, // possibly cast back to an integer type. if (!base) { return tryEmitAbsolute(destTy); } d1333 12 a1344 2 // Otherwise, try to emit the base. ConstantLValue result = tryEmitBase(base); d1346 3 a1348 3 // If that failed, we're done. llvm::Constant *value = result.Value; if (!value) return nullptr; d1350 1 a1350 69 // Apply the offset if necessary and not already done. if (!result.HasOffsetApplied) { value = applyOffset(value); } // Convert to the appropriate type; this could be an lvalue for // an integer. FIXME: performAddrSpaceCast if (isa(destTy)) return llvm::ConstantExpr::getPointerCast(value, destTy); return llvm::ConstantExpr::getPtrToInt(value, destTy); } /// Try to emit an absolute l-value, such as a null pointer or an integer /// bitcast to pointer type. llvm::Constant * ConstantLValueEmitter::tryEmitAbsolute(llvm::Type *destTy) { auto offset = getOffset(); // If we're producing a pointer, this is easy. if (auto destPtrTy = cast(destTy)) { if (Value.isNullPointer()) { // FIXME: integer offsets from non-zero null pointers. return CGM.getNullPointer(destPtrTy, DestType); } // Convert the integer to a pointer-sized integer before converting it // to a pointer. // FIXME: signedness depends on the original integer type. auto intptrTy = CGM.getDataLayout().getIntPtrType(destPtrTy); llvm::Constant *C = offset; C = llvm::ConstantExpr::getIntegerCast(getOffset(), intptrTy, /*isSigned*/ false); C = llvm::ConstantExpr::getIntToPtr(C, destPtrTy); return C; } // Otherwise, we're basically returning an integer constant. // FIXME: this does the wrong thing with ptrtoint of a null pointer, // but since we don't know the original pointer type, there's not much // we can do about it. auto C = getOffset(); C = llvm::ConstantExpr::getIntegerCast(C, destTy, /*isSigned*/ false); return C; } ConstantLValue ConstantLValueEmitter::tryEmitBase(const APValue::LValueBase &base) { // Handle values. if (const ValueDecl *D = base.dyn_cast()) { if (D->hasAttr()) return CGM.GetWeakRefReference(D).getPointer(); if (auto FD = dyn_cast(D)) return CGM.GetAddrOfFunction(FD); if (auto VD = dyn_cast(D)) { // We can never refer to a variable with local storage. if (!VD->hasLocalStorage()) { if (VD->isFileVarDecl() || VD->hasExternalStorage()) return CGM.GetAddrOfGlobalVar(VD); if (VD->isLocalVarDecl()) { return CGM.getOrCreateStaticVarDecl( *VD, CGM.getLLVMLinkageVarDefinition(VD, /*isConstant=*/false)); } } a1351 66 return nullptr; } // Otherwise, it must be an expression. return Visit(base.get()); } ConstantLValue ConstantLValueEmitter::VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) { return tryEmitGlobalCompoundLiteral(CGM, Emitter.CGF, E); } ConstantLValue ConstantLValueEmitter::VisitStringLiteral(const StringLiteral *E) { return CGM.GetAddrOfConstantStringFromLiteral(E); } ConstantLValue ConstantLValueEmitter::VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { return CGM.GetAddrOfConstantStringFromObjCEncode(E); } ConstantLValue ConstantLValueEmitter::VisitObjCStringLiteral(const ObjCStringLiteral *E) { auto C = CGM.getObjCRuntime().GenerateConstantString(E->getString()); return C.getElementBitCast(CGM.getTypes().ConvertTypeForMem(E->getType())); } ConstantLValue ConstantLValueEmitter::VisitPredefinedExpr(const PredefinedExpr *E) { if (auto CGF = Emitter.CGF) { LValue Res = CGF->EmitPredefinedLValue(E); return cast(Res.getAddress()); } auto kind = E->getIdentType(); if (kind == PredefinedExpr::PrettyFunction) { return CGM.GetAddrOfConstantCString("top level", ".tmp"); } return CGM.GetAddrOfConstantCString("", ".tmp"); } ConstantLValue ConstantLValueEmitter::VisitAddrLabelExpr(const AddrLabelExpr *E) { assert(Emitter.CGF && "Invalid address of label expression outside function"); llvm::Constant *Ptr = Emitter.CGF->GetAddrOfLabel(E->getLabel()); Ptr = llvm::ConstantExpr::getBitCast(Ptr, CGM.getTypes().ConvertType(E->getType())); return Ptr; } ConstantLValue ConstantLValueEmitter::VisitCallExpr(const CallExpr *E) { unsigned builtin = E->getBuiltinCallee(); if (builtin != Builtin::BI__builtin___CFStringMakeConstantString && builtin != Builtin::BI__builtin___NSStringMakeConstantString) return nullptr; auto literal = cast(E->getArg(0)->IgnoreParenCasts()); if (builtin == Builtin::BI__builtin___NSStringMakeConstantString) { return CGM.getObjCRuntime().GenerateConstantString(literal); } else { // FIXME: need to deal with UCN conversion issues. return CGM.GetAddrOfConstantCFString(literal); a1352 46 } ConstantLValue ConstantLValueEmitter::VisitBlockExpr(const BlockExpr *E) { StringRef functionName; if (auto CGF = Emitter.CGF) functionName = CGF->CurFn->getName(); else functionName = "global"; return CGM.GetAddrOfGlobalBlock(E, functionName); } ConstantLValue ConstantLValueEmitter::VisitCXXTypeidExpr(const CXXTypeidExpr *E) { QualType T; if (E->isTypeOperand()) T = E->getTypeOperand(CGM.getContext()); else T = E->getExprOperand()->getType(); return CGM.GetAddrOfRTTIDescriptor(T); } ConstantLValue ConstantLValueEmitter::VisitCXXUuidofExpr(const CXXUuidofExpr *E) { return CGM.GetAddrOfUuidDescriptor(E); } ConstantLValue ConstantLValueEmitter::VisitMaterializeTemporaryExpr( const MaterializeTemporaryExpr *E) { assert(E->getStorageDuration() == SD_Static); SmallVector CommaLHSs; SmallVector Adjustments; const Expr *Inner = E->GetTemporaryExpr() ->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); return CGM.GetAddrOfGlobalTemporary(E, Inner); } llvm::Constant *ConstantEmitter::tryEmitPrivate(const APValue &Value, QualType DestType) { switch (Value.getKind()) { case APValue::Uninitialized: llvm_unreachable("Constant expressions should be initialized."); case APValue::LValue: return ConstantLValueEmitter(*this, Value, DestType).tryEmit(); d1354 1 a1354 1 return llvm::ConstantInt::get(CGM.getLLVMContext(), Value.getInt()); d1358 1 a1358 1 Complex[0] = llvm::ConstantInt::get(CGM.getLLVMContext(), d1360 1 a1360 1 Complex[1] = llvm::ConstantInt::get(CGM.getLLVMContext(), d1371 3 a1373 4 !CGM.getContext().getLangOpts().NativeHalfType && CGM.getContext().getTargetInfo().useFP16ConversionIntrinsics()) return llvm::ConstantInt::get(CGM.getLLVMContext(), Init.bitcastToAPInt()); d1375 1 a1375 1 return llvm::ConstantFP::get(CGM.getLLVMContext(), Init); d1380 1 a1380 1 Complex[0] = llvm::ConstantFP::get(CGM.getLLVMContext(), d1382 1 a1382 1 Complex[1] = llvm::ConstantFP::get(CGM.getLLVMContext(), d1397 1 a1397 1 Inits[I] = llvm::ConstantInt::get(CGM.getLLVMContext(), Elt.getInt()); d1399 1 a1399 1 Inits[I] = llvm::ConstantFP::get(CGM.getLLVMContext(), Elt.getFloat()); d1408 2 a1409 3 llvm::Constant *LHS = tryEmitPrivate(LHSExpr, LHSExpr->getType()); llvm::Constant *RHS = tryEmitPrivate(RHSExpr, RHSExpr->getType()); if (!LHS || !RHS) return nullptr; d1412 3 a1414 3 llvm::Type *ResultType = CGM.getTypes().ConvertType(DestType); LHS = llvm::ConstantExpr::getPtrToInt(LHS, CGM.IntPtrTy); RHS = llvm::ConstantExpr::getPtrToInt(RHS, CGM.IntPtrTy); d1424 1 a1424 1 return ConstStructBuilder::BuildStruct(*this, Value, DestType); d1426 1 a1426 2 const ConstantArrayType *CAT = CGM.getContext().getAsConstantArrayType(DestType); d1432 3 a1434 6 if (Value.hasArrayFiller()) { Filler = tryEmitAbstractForMemory(Value.getArrayFiller(), CAT->getElementType()); if (!Filler) return nullptr; } d1437 2 a1438 11 SmallVector Elts; if (Filler && Filler->isNullValue()) Elts.reserve(NumInitElts + 1); else Elts.reserve(NumElements); llvm::Type *CommonElementType = nullptr; for (unsigned I = 0; I < NumInitElts; ++I) { llvm::Constant *C = tryEmitPrivateForMemory( Value.getArrayInitializedElt(I), CAT->getElementType()); if (!C) return nullptr; d1440 16 d1463 13 a1475 2 return EmitArrayConstant(CGM, CAT, CommonElementType, NumElements, Elts, Filler); d1478 1 a1478 1 return CGM.getCXXABI().EmitMemberPointer(Value, DestType); d1483 12 d1510 1 a1510 1 return tryEmitGlobalCompoundLiteral(*this, nullptr, E); a1631 5 llvm::Constant *ConstantEmitter::emitNullForMemory(CodeGenModule &CGM, QualType T) { return emitForMemory(CGM, CGM.EmitNullConstant(T), T); } d1646 1 a1646 2 llvm::Constant *Element = ConstantEmitter::emitNullForMemory(*this, ElementTy); @ 1.1.1.10 log @Mark old LLVM instance as dead. @ text @@ 1.1.1.4.4.1 log @file CGExprConstant.cpp was added on branch tls-maxphys on 2014-08-19 23:47:27 +0000 @ text @d1 1501 @ 1.1.1.4.4.2 log @Rebase to HEAD as of a few days ago. @ text @a0 1501 //===--- CGExprConstant.cpp - Emit LLVM Code from Constant Expressions ----===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This contains code to emit Constant Expr nodes as LLVM code. // //===----------------------------------------------------------------------===// #include "CodeGenFunction.h" #include "CGCXXABI.h" #include "CGObjCRuntime.h" #include "CGRecordLayout.h" #include "CodeGenModule.h" #include "clang/AST/APValue.h" #include "clang/AST/ASTContext.h" #include "clang/AST/RecordLayout.h" #include "clang/AST/StmtVisitor.h" #include "clang/Basic/Builtins.h" #include "llvm/IR/Constants.h" #include "llvm/IR/DataLayout.h" #include "llvm/IR/Function.h" #include "llvm/IR/GlobalVariable.h" using namespace clang; using namespace CodeGen; //===----------------------------------------------------------------------===// // ConstStructBuilder //===----------------------------------------------------------------------===// namespace { class ConstStructBuilder { CodeGenModule &CGM; CodeGenFunction *CGF; bool Packed; CharUnits NextFieldOffsetInChars; CharUnits LLVMStructAlignment; SmallVector Elements; public: static llvm::Constant *BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, InitListExpr *ILE); static llvm::Constant *BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, const APValue &Value, QualType ValTy); private: ConstStructBuilder(CodeGenModule &CGM, CodeGenFunction *CGF) : CGM(CGM), CGF(CGF), Packed(false), NextFieldOffsetInChars(CharUnits::Zero()), LLVMStructAlignment(CharUnits::One()) { } void AppendField(const FieldDecl *Field, uint64_t FieldOffset, llvm::Constant *InitExpr); void AppendBytes(CharUnits FieldOffsetInChars, llvm::Constant *InitCst); void AppendBitField(const FieldDecl *Field, uint64_t FieldOffset, llvm::ConstantInt *InitExpr); void AppendPadding(CharUnits PadSize); void AppendTailPadding(CharUnits RecordSize); void ConvertStructToPacked(); bool Build(InitListExpr *ILE); void Build(const APValue &Val, const RecordDecl *RD, bool IsPrimaryBase, const CXXRecordDecl *VTableClass, CharUnits BaseOffset); llvm::Constant *Finalize(QualType Ty); CharUnits getAlignment(const llvm::Constant *C) const { if (Packed) return CharUnits::One(); return CharUnits::fromQuantity( CGM.getDataLayout().getABITypeAlignment(C->getType())); } CharUnits getSizeInChars(const llvm::Constant *C) const { return CharUnits::fromQuantity( CGM.getDataLayout().getTypeAllocSize(C->getType())); } }; void ConstStructBuilder:: AppendField(const FieldDecl *Field, uint64_t FieldOffset, llvm::Constant *InitCst) { const ASTContext &Context = CGM.getContext(); CharUnits FieldOffsetInChars = Context.toCharUnitsFromBits(FieldOffset); AppendBytes(FieldOffsetInChars, InitCst); } void ConstStructBuilder:: AppendBytes(CharUnits FieldOffsetInChars, llvm::Constant *InitCst) { assert(NextFieldOffsetInChars <= FieldOffsetInChars && "Field offset mismatch!"); CharUnits FieldAlignment = getAlignment(InitCst); // Round up the field offset to the alignment of the field type. CharUnits AlignedNextFieldOffsetInChars = NextFieldOffsetInChars.RoundUpToAlignment(FieldAlignment); if (AlignedNextFieldOffsetInChars > FieldOffsetInChars) { assert(!Packed && "Alignment is wrong even with a packed struct!"); // Convert the struct to a packed struct. ConvertStructToPacked(); AlignedNextFieldOffsetInChars = NextFieldOffsetInChars; } if (AlignedNextFieldOffsetInChars < FieldOffsetInChars) { // We need to append padding. AppendPadding(FieldOffsetInChars - NextFieldOffsetInChars); assert(NextFieldOffsetInChars == FieldOffsetInChars && "Did not add enough padding!"); AlignedNextFieldOffsetInChars = NextFieldOffsetInChars; } // Add the field. Elements.push_back(InitCst); NextFieldOffsetInChars = AlignedNextFieldOffsetInChars + getSizeInChars(InitCst); if (Packed) assert(LLVMStructAlignment == CharUnits::One() && "Packed struct not byte-aligned!"); else LLVMStructAlignment = std::max(LLVMStructAlignment, FieldAlignment); } void ConstStructBuilder::AppendBitField(const FieldDecl *Field, uint64_t FieldOffset, llvm::ConstantInt *CI) { const ASTContext &Context = CGM.getContext(); const uint64_t CharWidth = Context.getCharWidth(); uint64_t NextFieldOffsetInBits = Context.toBits(NextFieldOffsetInChars); if (FieldOffset > NextFieldOffsetInBits) { // We need to add padding. CharUnits PadSize = Context.toCharUnitsFromBits( llvm::RoundUpToAlignment(FieldOffset - NextFieldOffsetInBits, Context.getTargetInfo().getCharAlign())); AppendPadding(PadSize); } uint64_t FieldSize = Field->getBitWidthValue(Context); llvm::APInt FieldValue = CI->getValue(); // Promote the size of FieldValue if necessary // FIXME: This should never occur, but currently it can because initializer // constants are cast to bool, and because clang is not enforcing bitfield // width limits. if (FieldSize > FieldValue.getBitWidth()) FieldValue = FieldValue.zext(FieldSize); // Truncate the size of FieldValue to the bit field size. if (FieldSize < FieldValue.getBitWidth()) FieldValue = FieldValue.trunc(FieldSize); NextFieldOffsetInBits = Context.toBits(NextFieldOffsetInChars); if (FieldOffset < NextFieldOffsetInBits) { // Either part of the field or the entire field can go into the previous // byte. assert(!Elements.empty() && "Elements can't be empty!"); unsigned BitsInPreviousByte = NextFieldOffsetInBits - FieldOffset; bool FitsCompletelyInPreviousByte = BitsInPreviousByte >= FieldValue.getBitWidth(); llvm::APInt Tmp = FieldValue; if (!FitsCompletelyInPreviousByte) { unsigned NewFieldWidth = FieldSize - BitsInPreviousByte; if (CGM.getDataLayout().isBigEndian()) { Tmp = Tmp.lshr(NewFieldWidth); Tmp = Tmp.trunc(BitsInPreviousByte); // We want the remaining high bits. FieldValue = FieldValue.trunc(NewFieldWidth); } else { Tmp = Tmp.trunc(BitsInPreviousByte); // We want the remaining low bits. FieldValue = FieldValue.lshr(BitsInPreviousByte); FieldValue = FieldValue.trunc(NewFieldWidth); } } Tmp = Tmp.zext(CharWidth); if (CGM.getDataLayout().isBigEndian()) { if (FitsCompletelyInPreviousByte) Tmp = Tmp.shl(BitsInPreviousByte - FieldValue.getBitWidth()); } else { Tmp = Tmp.shl(CharWidth - BitsInPreviousByte); } // 'or' in the bits that go into the previous byte. llvm::Value *LastElt = Elements.back(); if (llvm::ConstantInt *Val = dyn_cast(LastElt)) Tmp |= Val->getValue(); else { assert(isa(LastElt)); // If there is an undef field that we're adding to, it can either be a // scalar undef (in which case, we just replace it with our field) or it // is an array. If it is an array, we have to pull one byte off the // array so that the other undef bytes stay around. if (!isa(LastElt->getType())) { // The undef padding will be a multibyte array, create a new smaller // padding and then an hole for our i8 to get plopped into. assert(isa(LastElt->getType()) && "Expected array padding of undefs"); llvm::ArrayType *AT = cast(LastElt->getType()); assert(AT->getElementType()->isIntegerTy(CharWidth) && AT->getNumElements() != 0 && "Expected non-empty array padding of undefs"); // Remove the padding array. NextFieldOffsetInChars -= CharUnits::fromQuantity(AT->getNumElements()); Elements.pop_back(); // Add the padding back in two chunks. AppendPadding(CharUnits::fromQuantity(AT->getNumElements()-1)); AppendPadding(CharUnits::One()); assert(isa(Elements.back()) && Elements.back()->getType()->isIntegerTy(CharWidth) && "Padding addition didn't work right"); } } Elements.back() = llvm::ConstantInt::get(CGM.getLLVMContext(), Tmp); if (FitsCompletelyInPreviousByte) return; } while (FieldValue.getBitWidth() > CharWidth) { llvm::APInt Tmp; if (CGM.getDataLayout().isBigEndian()) { // We want the high bits. Tmp = FieldValue.lshr(FieldValue.getBitWidth() - CharWidth).trunc(CharWidth); } else { // We want the low bits. Tmp = FieldValue.trunc(CharWidth); FieldValue = FieldValue.lshr(CharWidth); } Elements.push_back(llvm::ConstantInt::get(CGM.getLLVMContext(), Tmp)); ++NextFieldOffsetInChars; FieldValue = FieldValue.trunc(FieldValue.getBitWidth() - CharWidth); } assert(FieldValue.getBitWidth() > 0 && "Should have at least one bit left!"); assert(FieldValue.getBitWidth() <= CharWidth && "Should not have more than a byte left!"); if (FieldValue.getBitWidth() < CharWidth) { if (CGM.getDataLayout().isBigEndian()) { unsigned BitWidth = FieldValue.getBitWidth(); FieldValue = FieldValue.zext(CharWidth) << (CharWidth - BitWidth); } else FieldValue = FieldValue.zext(CharWidth); } // Append the last element. Elements.push_back(llvm::ConstantInt::get(CGM.getLLVMContext(), FieldValue)); ++NextFieldOffsetInChars; } void ConstStructBuilder::AppendPadding(CharUnits PadSize) { if (PadSize.isZero()) return; llvm::Type *Ty = CGM.Int8Ty; if (PadSize > CharUnits::One()) Ty = llvm::ArrayType::get(Ty, PadSize.getQuantity()); llvm::Constant *C = llvm::UndefValue::get(Ty); Elements.push_back(C); assert(getAlignment(C) == CharUnits::One() && "Padding must have 1 byte alignment!"); NextFieldOffsetInChars += getSizeInChars(C); } void ConstStructBuilder::AppendTailPadding(CharUnits RecordSize) { assert(NextFieldOffsetInChars <= RecordSize && "Size mismatch!"); AppendPadding(RecordSize - NextFieldOffsetInChars); } void ConstStructBuilder::ConvertStructToPacked() { SmallVector PackedElements; CharUnits ElementOffsetInChars = CharUnits::Zero(); for (unsigned i = 0, e = Elements.size(); i != e; ++i) { llvm::Constant *C = Elements[i]; CharUnits ElementAlign = CharUnits::fromQuantity( CGM.getDataLayout().getABITypeAlignment(C->getType())); CharUnits AlignedElementOffsetInChars = ElementOffsetInChars.RoundUpToAlignment(ElementAlign); if (AlignedElementOffsetInChars > ElementOffsetInChars) { // We need some padding. CharUnits NumChars = AlignedElementOffsetInChars - ElementOffsetInChars; llvm::Type *Ty = CGM.Int8Ty; if (NumChars > CharUnits::One()) Ty = llvm::ArrayType::get(Ty, NumChars.getQuantity()); llvm::Constant *Padding = llvm::UndefValue::get(Ty); PackedElements.push_back(Padding); ElementOffsetInChars += getSizeInChars(Padding); } PackedElements.push_back(C); ElementOffsetInChars += getSizeInChars(C); } assert(ElementOffsetInChars == NextFieldOffsetInChars && "Packing the struct changed its size!"); Elements.swap(PackedElements); LLVMStructAlignment = CharUnits::One(); Packed = true; } bool ConstStructBuilder::Build(InitListExpr *ILE) { RecordDecl *RD = ILE->getType()->getAs()->getDecl(); const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); unsigned FieldNo = 0; unsigned ElementNo = 0; for (RecordDecl::field_iterator Field = RD->field_begin(), FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) { // If this is a union, skip all the fields that aren't being initialized. if (RD->isUnion() && ILE->getInitializedFieldInUnion() != *Field) continue; // Don't emit anonymous bitfields, they just affect layout. if (Field->isUnnamedBitfield()) continue; // Get the initializer. A struct can include fields without initializers, // we just use explicit null values for them. llvm::Constant *EltInit; if (ElementNo < ILE->getNumInits()) EltInit = CGM.EmitConstantExpr(ILE->getInit(ElementNo++), Field->getType(), CGF); else EltInit = CGM.EmitNullConstant(Field->getType()); if (!EltInit) return false; if (!Field->isBitField()) { // Handle non-bitfield members. AppendField(*Field, Layout.getFieldOffset(FieldNo), EltInit); } else { // Otherwise we have a bitfield. AppendBitField(*Field, Layout.getFieldOffset(FieldNo), cast(EltInit)); } } return true; } namespace { struct BaseInfo { BaseInfo(const CXXRecordDecl *Decl, CharUnits Offset, unsigned Index) : Decl(Decl), Offset(Offset), Index(Index) { } const CXXRecordDecl *Decl; CharUnits Offset; unsigned Index; bool operator<(const BaseInfo &O) const { return Offset < O.Offset; } }; } void ConstStructBuilder::Build(const APValue &Val, const RecordDecl *RD, bool IsPrimaryBase, const CXXRecordDecl *VTableClass, CharUnits Offset) { const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); if (const CXXRecordDecl *CD = dyn_cast(RD)) { // Add a vtable pointer, if we need one and it hasn't already been added. if (CD->isDynamicClass() && !IsPrimaryBase) { llvm::Constant *VTableAddressPoint = CGM.getCXXABI().getVTableAddressPointForConstExpr( BaseSubobject(CD, Offset), VTableClass); AppendBytes(Offset, VTableAddressPoint); } // Accumulate and sort bases, in order to visit them in address order, which // may not be the same as declaration order. SmallVector Bases; Bases.reserve(CD->getNumBases()); unsigned BaseNo = 0; for (CXXRecordDecl::base_class_const_iterator Base = CD->bases_begin(), BaseEnd = CD->bases_end(); Base != BaseEnd; ++Base, ++BaseNo) { assert(!Base->isVirtual() && "should not have virtual bases here"); const CXXRecordDecl *BD = Base->getType()->getAsCXXRecordDecl(); CharUnits BaseOffset = Layout.getBaseClassOffset(BD); Bases.push_back(BaseInfo(BD, BaseOffset, BaseNo)); } std::stable_sort(Bases.begin(), Bases.end()); for (unsigned I = 0, N = Bases.size(); I != N; ++I) { BaseInfo &Base = Bases[I]; bool IsPrimaryBase = Layout.getPrimaryBase() == Base.Decl; Build(Val.getStructBase(Base.Index), Base.Decl, IsPrimaryBase, VTableClass, Offset + Base.Offset); } } unsigned FieldNo = 0; uint64_t OffsetBits = CGM.getContext().toBits(Offset); for (RecordDecl::field_iterator Field = RD->field_begin(), FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) { // If this is a union, skip all the fields that aren't being initialized. if (RD->isUnion() && Val.getUnionField() != *Field) continue; // Don't emit anonymous bitfields, they just affect layout. if (Field->isUnnamedBitfield()) continue; // Emit the value of the initializer. const APValue &FieldValue = RD->isUnion() ? Val.getUnionValue() : Val.getStructField(FieldNo); llvm::Constant *EltInit = CGM.EmitConstantValueForMemory(FieldValue, Field->getType(), CGF); assert(EltInit && "EmitConstantValue can't fail"); if (!Field->isBitField()) { // Handle non-bitfield members. AppendField(*Field, Layout.getFieldOffset(FieldNo) + OffsetBits, EltInit); } else { // Otherwise we have a bitfield. AppendBitField(*Field, Layout.getFieldOffset(FieldNo) + OffsetBits, cast(EltInit)); } } } llvm::Constant *ConstStructBuilder::Finalize(QualType Ty) { RecordDecl *RD = Ty->getAs()->getDecl(); const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); CharUnits LayoutSizeInChars = Layout.getSize(); if (NextFieldOffsetInChars > LayoutSizeInChars) { // If the struct is bigger than the size of the record type, // we must have a flexible array member at the end. assert(RD->hasFlexibleArrayMember() && "Must have flexible array member if struct is bigger than type!"); // No tail padding is necessary. } else { // Append tail padding if necessary. AppendTailPadding(LayoutSizeInChars); CharUnits LLVMSizeInChars = NextFieldOffsetInChars.RoundUpToAlignment(LLVMStructAlignment); // Check if we need to convert the struct to a packed struct. if (NextFieldOffsetInChars <= LayoutSizeInChars && LLVMSizeInChars > LayoutSizeInChars) { assert(!Packed && "Size mismatch!"); ConvertStructToPacked(); assert(NextFieldOffsetInChars <= LayoutSizeInChars && "Converting to packed did not help!"); } assert(LayoutSizeInChars == NextFieldOffsetInChars && "Tail padding mismatch!"); } // Pick the type to use. If the type is layout identical to the ConvertType // type then use it, otherwise use whatever the builder produced for us. llvm::StructType *STy = llvm::ConstantStruct::getTypeForElements(CGM.getLLVMContext(), Elements, Packed); llvm::Type *ValTy = CGM.getTypes().ConvertType(Ty); if (llvm::StructType *ValSTy = dyn_cast(ValTy)) { if (ValSTy->isLayoutIdentical(STy)) STy = ValSTy; } llvm::Constant *Result = llvm::ConstantStruct::get(STy, Elements); assert(NextFieldOffsetInChars.RoundUpToAlignment(getAlignment(Result)) == getSizeInChars(Result) && "Size mismatch!"); return Result; } llvm::Constant *ConstStructBuilder::BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, InitListExpr *ILE) { ConstStructBuilder Builder(CGM, CGF); if (!Builder.Build(ILE)) return nullptr; return Builder.Finalize(ILE->getType()); } llvm::Constant *ConstStructBuilder::BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, const APValue &Val, QualType ValTy) { ConstStructBuilder Builder(CGM, CGF); const RecordDecl *RD = ValTy->castAs()->getDecl(); const CXXRecordDecl *CD = dyn_cast(RD); Builder.Build(Val, RD, false, CD, CharUnits::Zero()); return Builder.Finalize(ValTy); } //===----------------------------------------------------------------------===// // ConstExprEmitter //===----------------------------------------------------------------------===// /// This class only needs to handle two cases: /// 1) Literals (this is used by APValue emission to emit literals). /// 2) Arrays, structs and unions (outside C++11 mode, we don't currently /// constant fold these types). class ConstExprEmitter : public StmtVisitor { CodeGenModule &CGM; CodeGenFunction *CGF; llvm::LLVMContext &VMContext; public: ConstExprEmitter(CodeGenModule &cgm, CodeGenFunction *cgf) : CGM(cgm), CGF(cgf), VMContext(cgm.getLLVMContext()) { } //===--------------------------------------------------------------------===// // Visitor Methods //===--------------------------------------------------------------------===// llvm::Constant *VisitStmt(Stmt *S) { return nullptr; } llvm::Constant *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } llvm::Constant * VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE) { return Visit(PE->getReplacement()); } llvm::Constant *VisitGenericSelectionExpr(GenericSelectionExpr *GE) { return Visit(GE->getResultExpr()); } llvm::Constant *VisitChooseExpr(ChooseExpr *CE) { return Visit(CE->getChosenSubExpr()); } llvm::Constant *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { return Visit(E->getInitializer()); } llvm::Constant *VisitCastExpr(CastExpr* E) { Expr *subExpr = E->getSubExpr(); llvm::Constant *C = CGM.EmitConstantExpr(subExpr, subExpr->getType(), CGF); if (!C) return nullptr; llvm::Type *destType = ConvertType(E->getType()); switch (E->getCastKind()) { case CK_ToUnion: { // GCC cast to union extension assert(E->getType()->isUnionType() && "Destination type is not union type!"); // Build a struct with the union sub-element as the first member, // and padded to the appropriate size SmallVector Elts; SmallVector Types; Elts.push_back(C); Types.push_back(C->getType()); unsigned CurSize = CGM.getDataLayout().getTypeAllocSize(C->getType()); unsigned TotalSize = CGM.getDataLayout().getTypeAllocSize(destType); assert(CurSize <= TotalSize && "Union size mismatch!"); if (unsigned NumPadBytes = TotalSize - CurSize) { llvm::Type *Ty = CGM.Int8Ty; if (NumPadBytes > 1) Ty = llvm::ArrayType::get(Ty, NumPadBytes); Elts.push_back(llvm::UndefValue::get(Ty)); Types.push_back(Ty); } llvm::StructType* STy = llvm::StructType::get(C->getType()->getContext(), Types, false); return llvm::ConstantStruct::get(STy, Elts); } case CK_AddressSpaceConversion: return llvm::ConstantExpr::getAddrSpaceCast(C, destType); case CK_LValueToRValue: case CK_AtomicToNonAtomic: case CK_NonAtomicToAtomic: case CK_NoOp: case CK_ConstructorConversion: return C; case CK_Dependent: llvm_unreachable("saw dependent cast!"); case CK_BuiltinFnToFnPtr: llvm_unreachable("builtin functions are handled elsewhere"); case CK_ReinterpretMemberPointer: case CK_DerivedToBaseMemberPointer: case CK_BaseToDerivedMemberPointer: return CGM.getCXXABI().EmitMemberPointerConversion(E, C); // These will never be supported. case CK_ObjCObjectLValueCast: case CK_ARCProduceObject: case CK_ARCConsumeObject: case CK_ARCReclaimReturnedObject: case CK_ARCExtendBlockObject: case CK_CopyAndAutoreleaseBlockObject: return nullptr; // These don't need to be handled here because Evaluate knows how to // evaluate them in the cases where they can be folded. case CK_BitCast: case CK_ToVoid: case CK_Dynamic: case CK_LValueBitCast: case CK_NullToMemberPointer: case CK_UserDefinedConversion: case CK_CPointerToObjCPointerCast: case CK_BlockPointerToObjCPointerCast: case CK_AnyPointerToBlockPointerCast: case CK_ArrayToPointerDecay: case CK_FunctionToPointerDecay: case CK_BaseToDerived: case CK_DerivedToBase: case CK_UncheckedDerivedToBase: case CK_MemberPointerToBoolean: case CK_VectorSplat: case CK_FloatingRealToComplex: case CK_FloatingComplexToReal: case CK_FloatingComplexToBoolean: case CK_FloatingComplexCast: case CK_FloatingComplexToIntegralComplex: case CK_IntegralRealToComplex: case CK_IntegralComplexToReal: case CK_IntegralComplexToBoolean: case CK_IntegralComplexCast: case CK_IntegralComplexToFloatingComplex: case CK_PointerToIntegral: case CK_PointerToBoolean: case CK_NullToPointer: case CK_IntegralCast: case CK_IntegralToPointer: case CK_IntegralToBoolean: case CK_IntegralToFloating: case CK_FloatingToIntegral: case CK_FloatingToBoolean: case CK_FloatingCast: case CK_ZeroToOCLEvent: return nullptr; } llvm_unreachable("Invalid CastKind"); } llvm::Constant *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { return Visit(DAE->getExpr()); } llvm::Constant *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) { // No need for a DefaultInitExprScope: we don't handle 'this' in a // constant expression. return Visit(DIE->getExpr()); } llvm::Constant *VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E) { return Visit(E->GetTemporaryExpr()); } llvm::Constant *EmitArrayInitialization(InitListExpr *ILE) { if (ILE->isStringLiteralInit()) return Visit(ILE->getInit(0)); llvm::ArrayType *AType = cast(ConvertType(ILE->getType())); llvm::Type *ElemTy = AType->getElementType(); unsigned NumInitElements = ILE->getNumInits(); unsigned NumElements = AType->getNumElements(); // Initialising an array requires us to automatically // initialise any elements that have not been initialised explicitly unsigned NumInitableElts = std::min(NumInitElements, NumElements); // Copy initializer elements. std::vector Elts; Elts.reserve(NumInitableElts + NumElements); bool RewriteType = false; for (unsigned i = 0; i < NumInitableElts; ++i) { Expr *Init = ILE->getInit(i); llvm::Constant *C = CGM.EmitConstantExpr(Init, Init->getType(), CGF); if (!C) return nullptr; RewriteType |= (C->getType() != ElemTy); Elts.push_back(C); } // Initialize remaining array elements. // FIXME: This doesn't handle member pointers correctly! llvm::Constant *fillC; if (Expr *filler = ILE->getArrayFiller()) fillC = CGM.EmitConstantExpr(filler, filler->getType(), CGF); else fillC = llvm::Constant::getNullValue(ElemTy); if (!fillC) return nullptr; RewriteType |= (fillC->getType() != ElemTy); Elts.resize(NumElements, fillC); if (RewriteType) { // FIXME: Try to avoid packing the array std::vector Types; Types.reserve(NumInitableElts + NumElements); for (unsigned i = 0, e = Elts.size(); i < e; ++i) Types.push_back(Elts[i]->getType()); llvm::StructType *SType = llvm::StructType::get(AType->getContext(), Types, true); return llvm::ConstantStruct::get(SType, Elts); } return llvm::ConstantArray::get(AType, Elts); } llvm::Constant *EmitRecordInitialization(InitListExpr *ILE) { return ConstStructBuilder::BuildStruct(CGM, CGF, ILE); } llvm::Constant *VisitImplicitValueInitExpr(ImplicitValueInitExpr* E) { return CGM.EmitNullConstant(E->getType()); } llvm::Constant *VisitInitListExpr(InitListExpr *ILE) { if (ILE->getType()->isArrayType()) return EmitArrayInitialization(ILE); if (ILE->getType()->isRecordType()) return EmitRecordInitialization(ILE); return nullptr; } llvm::Constant *VisitCXXConstructExpr(CXXConstructExpr *E) { if (!E->getConstructor()->isTrivial()) return nullptr; QualType Ty = E->getType(); // FIXME: We should not have to call getBaseElementType here. const RecordType *RT = CGM.getContext().getBaseElementType(Ty)->getAs(); const CXXRecordDecl *RD = cast(RT->getDecl()); // If the class doesn't have a trivial destructor, we can't emit it as a // constant expr. if (!RD->hasTrivialDestructor()) return nullptr; // Only copy and default constructors can be trivial. if (E->getNumArgs()) { assert(E->getNumArgs() == 1 && "trivial ctor with > 1 argument"); assert(E->getConstructor()->isCopyOrMoveConstructor() && "trivial ctor has argument but isn't a copy/move ctor"); Expr *Arg = E->getArg(0); assert(CGM.getContext().hasSameUnqualifiedType(Ty, Arg->getType()) && "argument to copy ctor is of wrong type"); return Visit(Arg); } return CGM.EmitNullConstant(Ty); } llvm::Constant *VisitStringLiteral(StringLiteral *E) { return CGM.GetConstantArrayFromStringLiteral(E); } llvm::Constant *VisitObjCEncodeExpr(ObjCEncodeExpr *E) { // This must be an @@encode initializing an array in a static initializer. // Don't emit it as the address of the string, emit the string data itself // as an inline array. std::string Str; CGM.getContext().getObjCEncodingForType(E->getEncodedType(), Str); QualType T = E->getType(); if (T->getTypeClass() == Type::TypeOfExpr) T = cast(T)->getUnderlyingExpr()->getType(); const ConstantArrayType *CAT = cast(T); // Resize the string to the right size, adding zeros at the end, or // truncating as needed. Str.resize(CAT->getSize().getZExtValue(), '\0'); return llvm::ConstantDataArray::getString(VMContext, Str, false); } llvm::Constant *VisitUnaryExtension(const UnaryOperator *E) { return Visit(E->getSubExpr()); } // Utility methods llvm::Type *ConvertType(QualType T) { return CGM.getTypes().ConvertType(T); } public: llvm::Constant *EmitLValue(APValue::LValueBase LVBase) { if (const ValueDecl *Decl = LVBase.dyn_cast()) { if (Decl->hasAttr()) return CGM.GetWeakRefReference(Decl); if (const FunctionDecl *FD = dyn_cast(Decl)) return CGM.GetAddrOfFunction(FD); if (const VarDecl* VD = dyn_cast(Decl)) { // We can never refer to a variable with local storage. if (!VD->hasLocalStorage()) { if (VD->isFileVarDecl() || VD->hasExternalStorage()) return CGM.GetAddrOfGlobalVar(VD); else if (VD->isLocalVarDecl()) return CGM.getStaticLocalDeclAddress(VD); } } return nullptr; } Expr *E = const_cast(LVBase.get()); switch (E->getStmtClass()) { default: break; case Expr::CompoundLiteralExprClass: { // Note that due to the nature of compound literals, this is guaranteed // to be the only use of the variable, so we just generate it here. CompoundLiteralExpr *CLE = cast(E); llvm::Constant* C = CGM.EmitConstantExpr(CLE->getInitializer(), CLE->getType(), CGF); // FIXME: "Leaked" on failure. if (C) C = new llvm::GlobalVariable(CGM.getModule(), C->getType(), E->getType().isConstant(CGM.getContext()), llvm::GlobalValue::InternalLinkage, C, ".compoundliteral", nullptr, llvm::GlobalVariable::NotThreadLocal, CGM.getContext().getTargetAddressSpace(E->getType())); return C; } case Expr::StringLiteralClass: return CGM.GetAddrOfConstantStringFromLiteral(cast(E)); case Expr::ObjCEncodeExprClass: return CGM.GetAddrOfConstantStringFromObjCEncode(cast(E)); case Expr::ObjCStringLiteralClass: { ObjCStringLiteral* SL = cast(E); llvm::Constant *C = CGM.getObjCRuntime().GenerateConstantString(SL->getString()); return llvm::ConstantExpr::getBitCast(C, ConvertType(E->getType())); } case Expr::PredefinedExprClass: { unsigned Type = cast(E)->getIdentType(); if (CGF) { LValue Res = CGF->EmitPredefinedLValue(cast(E)); return cast(Res.getAddress()); } else if (Type == PredefinedExpr::PrettyFunction) { return CGM.GetAddrOfConstantCString("top level", ".tmp"); } return CGM.GetAddrOfConstantCString("", ".tmp"); } case Expr::AddrLabelExprClass: { assert(CGF && "Invalid address of label expression outside function."); llvm::Constant *Ptr = CGF->GetAddrOfLabel(cast(E)->getLabel()); return llvm::ConstantExpr::getBitCast(Ptr, ConvertType(E->getType())); } case Expr::CallExprClass: { CallExpr* CE = cast(E); unsigned builtin = CE->getBuiltinCallee(); if (builtin != Builtin::BI__builtin___CFStringMakeConstantString && builtin != Builtin::BI__builtin___NSStringMakeConstantString) break; const Expr *Arg = CE->getArg(0)->IgnoreParenCasts(); const StringLiteral *Literal = cast(Arg); if (builtin == Builtin::BI__builtin___NSStringMakeConstantString) { return CGM.getObjCRuntime().GenerateConstantString(Literal); } // FIXME: need to deal with UCN conversion issues. return CGM.GetAddrOfConstantCFString(Literal); } case Expr::BlockExprClass: { std::string FunctionName; if (CGF) FunctionName = CGF->CurFn->getName(); else FunctionName = "global"; return CGM.GetAddrOfGlobalBlock(cast(E), FunctionName.c_str()); } case Expr::CXXTypeidExprClass: { CXXTypeidExpr *Typeid = cast(E); QualType T; if (Typeid->isTypeOperand()) T = Typeid->getTypeOperand(CGM.getContext()); else T = Typeid->getExprOperand()->getType(); return CGM.GetAddrOfRTTIDescriptor(T); } case Expr::CXXUuidofExprClass: { return CGM.GetAddrOfUuidDescriptor(cast(E)); } case Expr::MaterializeTemporaryExprClass: { MaterializeTemporaryExpr *MTE = cast(E); assert(MTE->getStorageDuration() == SD_Static); SmallVector CommaLHSs; SmallVector Adjustments; const Expr *Inner = MTE->GetTemporaryExpr() ->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); return CGM.GetAddrOfGlobalTemporary(MTE, Inner); } } return nullptr; } }; } // end anonymous namespace. llvm::Constant *CodeGenModule::EmitConstantInit(const VarDecl &D, CodeGenFunction *CGF) { // Make a quick check if variable can be default NULL initialized // and avoid going through rest of code which may do, for c++11, // initialization of memory to all NULLs. if (!D.hasLocalStorage()) { QualType Ty = D.getType(); if (Ty->isArrayType()) Ty = Context.getBaseElementType(Ty); if (Ty->isRecordType()) if (const CXXConstructExpr *E = dyn_cast_or_null(D.getInit())) { const CXXConstructorDecl *CD = E->getConstructor(); if (CD->isTrivial() && CD->isDefaultConstructor()) return EmitNullConstant(D.getType()); } } if (const APValue *Value = D.evaluateValue()) return EmitConstantValueForMemory(*Value, D.getType(), CGF); // FIXME: Implement C++11 [basic.start.init]p2: if the initializer of a // reference is a constant expression, and the reference binds to a temporary, // then constant initialization is performed. ConstExprEmitter will // incorrectly emit a prvalue constant in this case, and the calling code // interprets that as the (pointer) value of the reference, rather than the // desired value of the referee. if (D.getType()->isReferenceType()) return nullptr; const Expr *E = D.getInit(); assert(E && "No initializer to emit"); llvm::Constant* C = ConstExprEmitter(*this, CGF).Visit(const_cast(E)); if (C && C->getType()->isIntegerTy(1)) { llvm::Type *BoolTy = getTypes().ConvertTypeForMem(E->getType()); C = llvm::ConstantExpr::getZExt(C, BoolTy); } return C; } llvm::Constant *CodeGenModule::EmitConstantExpr(const Expr *E, QualType DestType, CodeGenFunction *CGF) { Expr::EvalResult Result; bool Success = false; if (DestType->isReferenceType()) Success = E->EvaluateAsLValue(Result, Context); else Success = E->EvaluateAsRValue(Result, Context); llvm::Constant *C = nullptr; if (Success && !Result.HasSideEffects) C = EmitConstantValue(Result.Val, DestType, CGF); else C = ConstExprEmitter(*this, CGF).Visit(const_cast(E)); if (C && C->getType()->isIntegerTy(1)) { llvm::Type *BoolTy = getTypes().ConvertTypeForMem(E->getType()); C = llvm::ConstantExpr::getZExt(C, BoolTy); } return C; } llvm::Constant *CodeGenModule::EmitConstantValue(const APValue &Value, QualType DestType, CodeGenFunction *CGF) { // For an _Atomic-qualified constant, we may need to add tail padding. if (auto *AT = DestType->getAs()) { QualType InnerType = AT->getValueType(); auto *Inner = EmitConstantValue(Value, InnerType, CGF); uint64_t InnerSize = Context.getTypeSize(InnerType); uint64_t OuterSize = Context.getTypeSize(DestType); if (InnerSize == OuterSize) return Inner; assert(InnerSize < OuterSize && "emitted over-large constant for atomic"); llvm::Constant *Elts[] = { Inner, llvm::ConstantAggregateZero::get( llvm::ArrayType::get(Int8Ty, (OuterSize - InnerSize) / 8)) }; return llvm::ConstantStruct::getAnon(Elts); } switch (Value.getKind()) { case APValue::Uninitialized: llvm_unreachable("Constant expressions should be initialized."); case APValue::LValue: { llvm::Type *DestTy = getTypes().ConvertTypeForMem(DestType); llvm::Constant *Offset = llvm::ConstantInt::get(Int64Ty, Value.getLValueOffset().getQuantity()); llvm::Constant *C; if (APValue::LValueBase LVBase = Value.getLValueBase()) { // An array can be represented as an lvalue referring to the base. if (isa(DestTy)) { assert(Offset->isNullValue() && "offset on array initializer"); return ConstExprEmitter(*this, CGF).Visit( const_cast(LVBase.get())); } C = ConstExprEmitter(*this, CGF).EmitLValue(LVBase); // Apply offset if necessary. if (!Offset->isNullValue()) { unsigned AS = C->getType()->getPointerAddressSpace(); llvm::Type *CharPtrTy = Int8Ty->getPointerTo(AS); llvm::Constant *Casted = llvm::ConstantExpr::getBitCast(C, CharPtrTy); Casted = llvm::ConstantExpr::getGetElementPtr(Casted, Offset); C = llvm::ConstantExpr::getPointerCast(Casted, C->getType()); } // Convert to the appropriate type; this could be an lvalue for // an integer. if (isa(DestTy)) return llvm::ConstantExpr::getPointerCast(C, DestTy); return llvm::ConstantExpr::getPtrToInt(C, DestTy); } else { C = Offset; // Convert to the appropriate type; this could be an lvalue for // an integer. if (isa(DestTy)) return llvm::ConstantExpr::getIntToPtr(C, DestTy); // If the types don't match this should only be a truncate. if (C->getType() != DestTy) return llvm::ConstantExpr::getTrunc(C, DestTy); return C; } } case APValue::Int: return llvm::ConstantInt::get(VMContext, Value.getInt()); case APValue::ComplexInt: { llvm::Constant *Complex[2]; Complex[0] = llvm::ConstantInt::get(VMContext, Value.getComplexIntReal()); Complex[1] = llvm::ConstantInt::get(VMContext, Value.getComplexIntImag()); // FIXME: the target may want to specify that this is packed. llvm::StructType *STy = llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType(), NULL); return llvm::ConstantStruct::get(STy, Complex); } case APValue::Float: { const llvm::APFloat &Init = Value.getFloat(); if (&Init.getSemantics() == &llvm::APFloat::IEEEhalf && !Context.getLangOpts().NativeHalfType) return llvm::ConstantInt::get(VMContext, Init.bitcastToAPInt()); else return llvm::ConstantFP::get(VMContext, Init); } case APValue::ComplexFloat: { llvm::Constant *Complex[2]; Complex[0] = llvm::ConstantFP::get(VMContext, Value.getComplexFloatReal()); Complex[1] = llvm::ConstantFP::get(VMContext, Value.getComplexFloatImag()); // FIXME: the target may want to specify that this is packed. llvm::StructType *STy = llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType(), NULL); return llvm::ConstantStruct::get(STy, Complex); } case APValue::Vector: { SmallVector Inits; unsigned NumElts = Value.getVectorLength(); for (unsigned i = 0; i != NumElts; ++i) { const APValue &Elt = Value.getVectorElt(i); if (Elt.isInt()) Inits.push_back(llvm::ConstantInt::get(VMContext, Elt.getInt())); else Inits.push_back(llvm::ConstantFP::get(VMContext, Elt.getFloat())); } return llvm::ConstantVector::get(Inits); } case APValue::AddrLabelDiff: { const AddrLabelExpr *LHSExpr = Value.getAddrLabelDiffLHS(); const AddrLabelExpr *RHSExpr = Value.getAddrLabelDiffRHS(); llvm::Constant *LHS = EmitConstantExpr(LHSExpr, LHSExpr->getType(), CGF); llvm::Constant *RHS = EmitConstantExpr(RHSExpr, RHSExpr->getType(), CGF); // Compute difference llvm::Type *ResultType = getTypes().ConvertType(DestType); LHS = llvm::ConstantExpr::getPtrToInt(LHS, IntPtrTy); RHS = llvm::ConstantExpr::getPtrToInt(RHS, IntPtrTy); llvm::Constant *AddrLabelDiff = llvm::ConstantExpr::getSub(LHS, RHS); // LLVM is a bit sensitive about the exact format of the // address-of-label difference; make sure to truncate after // the subtraction. return llvm::ConstantExpr::getTruncOrBitCast(AddrLabelDiff, ResultType); } case APValue::Struct: case APValue::Union: return ConstStructBuilder::BuildStruct(*this, CGF, Value, DestType); case APValue::Array: { const ArrayType *CAT = Context.getAsArrayType(DestType); unsigned NumElements = Value.getArraySize(); unsigned NumInitElts = Value.getArrayInitializedElts(); std::vector Elts; Elts.reserve(NumElements); // Emit array filler, if there is one. llvm::Constant *Filler = nullptr; if (Value.hasArrayFiller()) Filler = EmitConstantValueForMemory(Value.getArrayFiller(), CAT->getElementType(), CGF); // Emit initializer elements. llvm::Type *CommonElementType = nullptr; for (unsigned I = 0; I < NumElements; ++I) { llvm::Constant *C = Filler; if (I < NumInitElts) C = EmitConstantValueForMemory(Value.getArrayInitializedElt(I), CAT->getElementType(), CGF); else assert(Filler && "Missing filler for implicit elements of initializer"); if (I == 0) CommonElementType = C->getType(); else if (C->getType() != CommonElementType) CommonElementType = nullptr; Elts.push_back(C); } if (!CommonElementType) { // FIXME: Try to avoid packing the array std::vector Types; Types.reserve(NumElements); for (unsigned i = 0, e = Elts.size(); i < e; ++i) Types.push_back(Elts[i]->getType()); llvm::StructType *SType = llvm::StructType::get(VMContext, Types, true); return llvm::ConstantStruct::get(SType, Elts); } llvm::ArrayType *AType = llvm::ArrayType::get(CommonElementType, NumElements); return llvm::ConstantArray::get(AType, Elts); } case APValue::MemberPointer: return getCXXABI().EmitMemberPointer(Value, DestType); } llvm_unreachable("Unknown APValue kind"); } llvm::Constant * CodeGenModule::EmitConstantValueForMemory(const APValue &Value, QualType DestType, CodeGenFunction *CGF) { llvm::Constant *C = EmitConstantValue(Value, DestType, CGF); if (C->getType()->isIntegerTy(1)) { llvm::Type *BoolTy = getTypes().ConvertTypeForMem(DestType); C = llvm::ConstantExpr::getZExt(C, BoolTy); } return C; } llvm::Constant * CodeGenModule::GetAddrOfConstantCompoundLiteral(const CompoundLiteralExpr *E) { assert(E->isFileScope() && "not a file-scope compound literal expr"); return ConstExprEmitter(*this, nullptr).EmitLValue(E); } llvm::Constant * CodeGenModule::getMemberPointerConstant(const UnaryOperator *uo) { // Member pointer constants always have a very particular form. const MemberPointerType *type = cast(uo->getType()); const ValueDecl *decl = cast(uo->getSubExpr())->getDecl(); // A member function pointer. if (const CXXMethodDecl *method = dyn_cast(decl)) return getCXXABI().EmitMemberPointer(method); // Otherwise, a member data pointer. uint64_t fieldOffset = getContext().getFieldOffset(decl); CharUnits chars = getContext().toCharUnitsFromBits((int64_t) fieldOffset); return getCXXABI().EmitMemberDataPointer(type, chars); } static void FillInNullDataMemberPointers(CodeGenModule &CGM, QualType T, SmallVectorImpl &Elements, uint64_t StartOffset) { assert(StartOffset % CGM.getContext().getCharWidth() == 0 && "StartOffset not byte aligned!"); if (CGM.getTypes().isZeroInitializable(T)) return; if (const ConstantArrayType *CAT = CGM.getContext().getAsConstantArrayType(T)) { QualType ElementTy = CAT->getElementType(); uint64_t ElementSize = CGM.getContext().getTypeSize(ElementTy); for (uint64_t I = 0, E = CAT->getSize().getZExtValue(); I != E; ++I) { FillInNullDataMemberPointers(CGM, ElementTy, Elements, StartOffset + I * ElementSize); } } else if (const RecordType *RT = T->getAs()) { const CXXRecordDecl *RD = cast(RT->getDecl()); const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); // Go through all bases and fill in any null pointer to data members. for (const auto &I : RD->bases()) { if (I.isVirtual()) { // Ignore virtual bases. continue; } const CXXRecordDecl *BaseDecl = cast(I.getType()->getAs()->getDecl()); // Ignore empty bases. if (BaseDecl->isEmpty()) continue; // Ignore bases that don't have any pointer to data members. if (CGM.getTypes().isZeroInitializable(BaseDecl)) continue; uint64_t BaseOffset = CGM.getContext().toBits(Layout.getBaseClassOffset(BaseDecl)); FillInNullDataMemberPointers(CGM, I.getType(), Elements, StartOffset + BaseOffset); } // Visit all fields. unsigned FieldNo = 0; for (RecordDecl::field_iterator I = RD->field_begin(), E = RD->field_end(); I != E; ++I, ++FieldNo) { QualType FieldType = I->getType(); if (CGM.getTypes().isZeroInitializable(FieldType)) continue; uint64_t FieldOffset = StartOffset + Layout.getFieldOffset(FieldNo); FillInNullDataMemberPointers(CGM, FieldType, Elements, FieldOffset); } } else { assert(T->isMemberPointerType() && "Should only see member pointers here!"); assert(!T->getAs()->getPointeeType()->isFunctionType() && "Should only see pointers to data members here!"); CharUnits StartIndex = CGM.getContext().toCharUnitsFromBits(StartOffset); CharUnits EndIndex = StartIndex + CGM.getContext().getTypeSizeInChars(T); // FIXME: hardcodes Itanium member pointer representation! llvm::Constant *NegativeOne = llvm::ConstantInt::get(CGM.Int8Ty, -1ULL, /*isSigned*/true); // Fill in the null data member pointer. for (CharUnits I = StartIndex; I != EndIndex; ++I) Elements[I.getQuantity()] = NegativeOne; } } static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM, llvm::Type *baseType, const CXXRecordDecl *base); static llvm::Constant *EmitNullConstant(CodeGenModule &CGM, const CXXRecordDecl *record, bool asCompleteObject) { const CGRecordLayout &layout = CGM.getTypes().getCGRecordLayout(record); llvm::StructType *structure = (asCompleteObject ? layout.getLLVMType() : layout.getBaseSubobjectLLVMType()); unsigned numElements = structure->getNumElements(); std::vector elements(numElements); // Fill in all the bases. for (const auto &I : record->bases()) { if (I.isVirtual()) { // Ignore virtual bases; if we're laying out for a complete // object, we'll lay these out later. continue; } const CXXRecordDecl *base = cast(I.getType()->castAs()->getDecl()); // Ignore empty bases. if (base->isEmpty()) continue; unsigned fieldIndex = layout.getNonVirtualBaseLLVMFieldNo(base); llvm::Type *baseType = structure->getElementType(fieldIndex); elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base); } // Fill in all the fields. for (const auto *Field : record->fields()) { // Fill in non-bitfields. (Bitfields always use a zero pattern, which we // will fill in later.) if (!Field->isBitField()) { unsigned fieldIndex = layout.getLLVMFieldNo(Field); elements[fieldIndex] = CGM.EmitNullConstant(Field->getType()); } // For unions, stop after the first named field. if (record->isUnion() && Field->getDeclName()) break; } // Fill in the virtual bases, if we're working with the complete object. if (asCompleteObject) { for (const auto &I : record->vbases()) { const CXXRecordDecl *base = cast(I.getType()->castAs()->getDecl()); // Ignore empty bases. if (base->isEmpty()) continue; unsigned fieldIndex = layout.getVirtualBaseIndex(base); // We might have already laid this field out. if (elements[fieldIndex]) continue; llvm::Type *baseType = structure->getElementType(fieldIndex); elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base); } } // Now go through all other fields and zero them out. for (unsigned i = 0; i != numElements; ++i) { if (!elements[i]) elements[i] = llvm::Constant::getNullValue(structure->getElementType(i)); } return llvm::ConstantStruct::get(structure, elements); } /// Emit the null constant for a base subobject. static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM, llvm::Type *baseType, const CXXRecordDecl *base) { const CGRecordLayout &baseLayout = CGM.getTypes().getCGRecordLayout(base); // Just zero out bases that don't have any pointer to data members. if (baseLayout.isZeroInitializableAsBase()) return llvm::Constant::getNullValue(baseType); // If the base type is a struct, we can just use its null constant. if (isa(baseType)) { return EmitNullConstant(CGM, base, /*complete*/ false); } // Otherwise, some bases are represented as arrays of i8 if the size // of the base is smaller than its corresponding LLVM type. Figure // out how many elements this base array has. llvm::ArrayType *baseArrayType = cast(baseType); unsigned numBaseElements = baseArrayType->getNumElements(); // Fill in null data member pointers. SmallVector baseElements(numBaseElements); FillInNullDataMemberPointers(CGM, CGM.getContext().getTypeDeclType(base), baseElements, 0); // Now go through all other elements and zero them out. if (numBaseElements) { llvm::Constant *i8_zero = llvm::Constant::getNullValue(CGM.Int8Ty); for (unsigned i = 0; i != numBaseElements; ++i) { if (!baseElements[i]) baseElements[i] = i8_zero; } } return llvm::ConstantArray::get(baseArrayType, baseElements); } llvm::Constant *CodeGenModule::EmitNullConstant(QualType T) { if (getTypes().isZeroInitializable(T)) return llvm::Constant::getNullValue(getTypes().ConvertTypeForMem(T)); if (const ConstantArrayType *CAT = Context.getAsConstantArrayType(T)) { llvm::ArrayType *ATy = cast(getTypes().ConvertTypeForMem(T)); QualType ElementTy = CAT->getElementType(); llvm::Constant *Element = EmitNullConstant(ElementTy); unsigned NumElements = CAT->getSize().getZExtValue(); if (Element->isNullValue()) return llvm::ConstantAggregateZero::get(ATy); SmallVector Array(NumElements, Element); return llvm::ConstantArray::get(ATy, Array); } if (const RecordType *RT = T->getAs()) { const CXXRecordDecl *RD = cast(RT->getDecl()); return ::EmitNullConstant(*this, RD, /*complete object*/ true); } assert(T->isMemberPointerType() && "Should only see member pointers here!"); assert(!T->getAs()->getPointeeType()->isFunctionType() && "Should only see pointers to data members here!"); // Itanium C++ ABI 2.3: // A NULL pointer is represented as -1. return getCXXABI().EmitNullMemberPointer(T->castAs()); } llvm::Constant * CodeGenModule::EmitNullConstantForBase(const CXXRecordDecl *Record) { return ::EmitNullConstant(*this, Record, false); } @ 1.1.1.2.4.1 log @file CGExprConstant.cpp was added on branch yamt-pagecache on 2014-05-22 16:18:26 +0000 @ text @d1 1483 @ 1.1.1.2.4.2 log @sync with head. for a reference, the tree before this commit was tagged as yamt-pagecache-tag8. this commit was splitted into small chunks to avoid a limitation of cvs. ("Protocol error: too many arguments") @ text @a0 1483 //===--- CGExprConstant.cpp - Emit LLVM Code from Constant Expressions ----===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This contains code to emit Constant Expr nodes as LLVM code. // //===----------------------------------------------------------------------===// #include "CodeGenFunction.h" #include "CGCXXABI.h" #include "CGObjCRuntime.h" #include "CGRecordLayout.h" #include "CodeGenModule.h" #include "clang/AST/APValue.h" #include "clang/AST/ASTContext.h" #include "clang/AST/RecordLayout.h" #include "clang/AST/StmtVisitor.h" #include "clang/Basic/Builtins.h" #include "llvm/IR/Constants.h" #include "llvm/IR/DataLayout.h" #include "llvm/IR/Function.h" #include "llvm/IR/GlobalVariable.h" using namespace clang; using namespace CodeGen; //===----------------------------------------------------------------------===// // ConstStructBuilder //===----------------------------------------------------------------------===// namespace { class ConstStructBuilder { CodeGenModule &CGM; CodeGenFunction *CGF; bool Packed; CharUnits NextFieldOffsetInChars; CharUnits LLVMStructAlignment; SmallVector Elements; public: static llvm::Constant *BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, InitListExpr *ILE); static llvm::Constant *BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, const APValue &Value, QualType ValTy); private: ConstStructBuilder(CodeGenModule &CGM, CodeGenFunction *CGF) : CGM(CGM), CGF(CGF), Packed(false), NextFieldOffsetInChars(CharUnits::Zero()), LLVMStructAlignment(CharUnits::One()) { } void AppendField(const FieldDecl *Field, uint64_t FieldOffset, llvm::Constant *InitExpr); void AppendBytes(CharUnits FieldOffsetInChars, llvm::Constant *InitCst); void AppendBitField(const FieldDecl *Field, uint64_t FieldOffset, llvm::ConstantInt *InitExpr); void AppendPadding(CharUnits PadSize); void AppendTailPadding(CharUnits RecordSize); void ConvertStructToPacked(); bool Build(InitListExpr *ILE); void Build(const APValue &Val, const RecordDecl *RD, bool IsPrimaryBase, const CXXRecordDecl *VTableClass, CharUnits BaseOffset); llvm::Constant *Finalize(QualType Ty); CharUnits getAlignment(const llvm::Constant *C) const { if (Packed) return CharUnits::One(); return CharUnits::fromQuantity( CGM.getDataLayout().getABITypeAlignment(C->getType())); } CharUnits getSizeInChars(const llvm::Constant *C) const { return CharUnits::fromQuantity( CGM.getDataLayout().getTypeAllocSize(C->getType())); } }; void ConstStructBuilder:: AppendField(const FieldDecl *Field, uint64_t FieldOffset, llvm::Constant *InitCst) { const ASTContext &Context = CGM.getContext(); CharUnits FieldOffsetInChars = Context.toCharUnitsFromBits(FieldOffset); AppendBytes(FieldOffsetInChars, InitCst); } void ConstStructBuilder:: AppendBytes(CharUnits FieldOffsetInChars, llvm::Constant *InitCst) { assert(NextFieldOffsetInChars <= FieldOffsetInChars && "Field offset mismatch!"); CharUnits FieldAlignment = getAlignment(InitCst); // Round up the field offset to the alignment of the field type. CharUnits AlignedNextFieldOffsetInChars = NextFieldOffsetInChars.RoundUpToAlignment(FieldAlignment); if (AlignedNextFieldOffsetInChars > FieldOffsetInChars) { assert(!Packed && "Alignment is wrong even with a packed struct!"); // Convert the struct to a packed struct. ConvertStructToPacked(); AlignedNextFieldOffsetInChars = NextFieldOffsetInChars; } if (AlignedNextFieldOffsetInChars < FieldOffsetInChars) { // We need to append padding. AppendPadding(FieldOffsetInChars - NextFieldOffsetInChars); assert(NextFieldOffsetInChars == FieldOffsetInChars && "Did not add enough padding!"); AlignedNextFieldOffsetInChars = NextFieldOffsetInChars; } // Add the field. Elements.push_back(InitCst); NextFieldOffsetInChars = AlignedNextFieldOffsetInChars + getSizeInChars(InitCst); if (Packed) assert(LLVMStructAlignment == CharUnits::One() && "Packed struct not byte-aligned!"); else LLVMStructAlignment = std::max(LLVMStructAlignment, FieldAlignment); } void ConstStructBuilder::AppendBitField(const FieldDecl *Field, uint64_t FieldOffset, llvm::ConstantInt *CI) { const ASTContext &Context = CGM.getContext(); const uint64_t CharWidth = Context.getCharWidth(); uint64_t NextFieldOffsetInBits = Context.toBits(NextFieldOffsetInChars); if (FieldOffset > NextFieldOffsetInBits) { // We need to add padding. CharUnits PadSize = Context.toCharUnitsFromBits( llvm::RoundUpToAlignment(FieldOffset - NextFieldOffsetInBits, Context.getTargetInfo().getCharAlign())); AppendPadding(PadSize); } uint64_t FieldSize = Field->getBitWidthValue(Context); llvm::APInt FieldValue = CI->getValue(); // Promote the size of FieldValue if necessary // FIXME: This should never occur, but currently it can because initializer // constants are cast to bool, and because clang is not enforcing bitfield // width limits. if (FieldSize > FieldValue.getBitWidth()) FieldValue = FieldValue.zext(FieldSize); // Truncate the size of FieldValue to the bit field size. if (FieldSize < FieldValue.getBitWidth()) FieldValue = FieldValue.trunc(FieldSize); NextFieldOffsetInBits = Context.toBits(NextFieldOffsetInChars); if (FieldOffset < NextFieldOffsetInBits) { // Either part of the field or the entire field can go into the previous // byte. assert(!Elements.empty() && "Elements can't be empty!"); unsigned BitsInPreviousByte = NextFieldOffsetInBits - FieldOffset; bool FitsCompletelyInPreviousByte = BitsInPreviousByte >= FieldValue.getBitWidth(); llvm::APInt Tmp = FieldValue; if (!FitsCompletelyInPreviousByte) { unsigned NewFieldWidth = FieldSize - BitsInPreviousByte; if (CGM.getDataLayout().isBigEndian()) { Tmp = Tmp.lshr(NewFieldWidth); Tmp = Tmp.trunc(BitsInPreviousByte); // We want the remaining high bits. FieldValue = FieldValue.trunc(NewFieldWidth); } else { Tmp = Tmp.trunc(BitsInPreviousByte); // We want the remaining low bits. FieldValue = FieldValue.lshr(BitsInPreviousByte); FieldValue = FieldValue.trunc(NewFieldWidth); } } Tmp = Tmp.zext(CharWidth); if (CGM.getDataLayout().isBigEndian()) { if (FitsCompletelyInPreviousByte) Tmp = Tmp.shl(BitsInPreviousByte - FieldValue.getBitWidth()); } else { Tmp = Tmp.shl(CharWidth - BitsInPreviousByte); } // 'or' in the bits that go into the previous byte. llvm::Value *LastElt = Elements.back(); if (llvm::ConstantInt *Val = dyn_cast(LastElt)) Tmp |= Val->getValue(); else { assert(isa(LastElt)); // If there is an undef field that we're adding to, it can either be a // scalar undef (in which case, we just replace it with our field) or it // is an array. If it is an array, we have to pull one byte off the // array so that the other undef bytes stay around. if (!isa(LastElt->getType())) { // The undef padding will be a multibyte array, create a new smaller // padding and then an hole for our i8 to get plopped into. assert(isa(LastElt->getType()) && "Expected array padding of undefs"); llvm::ArrayType *AT = cast(LastElt->getType()); assert(AT->getElementType()->isIntegerTy(CharWidth) && AT->getNumElements() != 0 && "Expected non-empty array padding of undefs"); // Remove the padding array. NextFieldOffsetInChars -= CharUnits::fromQuantity(AT->getNumElements()); Elements.pop_back(); // Add the padding back in two chunks. AppendPadding(CharUnits::fromQuantity(AT->getNumElements()-1)); AppendPadding(CharUnits::One()); assert(isa(Elements.back()) && Elements.back()->getType()->isIntegerTy(CharWidth) && "Padding addition didn't work right"); } } Elements.back() = llvm::ConstantInt::get(CGM.getLLVMContext(), Tmp); if (FitsCompletelyInPreviousByte) return; } while (FieldValue.getBitWidth() > CharWidth) { llvm::APInt Tmp; if (CGM.getDataLayout().isBigEndian()) { // We want the high bits. Tmp = FieldValue.lshr(FieldValue.getBitWidth() - CharWidth).trunc(CharWidth); } else { // We want the low bits. Tmp = FieldValue.trunc(CharWidth); FieldValue = FieldValue.lshr(CharWidth); } Elements.push_back(llvm::ConstantInt::get(CGM.getLLVMContext(), Tmp)); ++NextFieldOffsetInChars; FieldValue = FieldValue.trunc(FieldValue.getBitWidth() - CharWidth); } assert(FieldValue.getBitWidth() > 0 && "Should have at least one bit left!"); assert(FieldValue.getBitWidth() <= CharWidth && "Should not have more than a byte left!"); if (FieldValue.getBitWidth() < CharWidth) { if (CGM.getDataLayout().isBigEndian()) { unsigned BitWidth = FieldValue.getBitWidth(); FieldValue = FieldValue.zext(CharWidth) << (CharWidth - BitWidth); } else FieldValue = FieldValue.zext(CharWidth); } // Append the last element. Elements.push_back(llvm::ConstantInt::get(CGM.getLLVMContext(), FieldValue)); ++NextFieldOffsetInChars; } void ConstStructBuilder::AppendPadding(CharUnits PadSize) { if (PadSize.isZero()) return; llvm::Type *Ty = CGM.Int8Ty; if (PadSize > CharUnits::One()) Ty = llvm::ArrayType::get(Ty, PadSize.getQuantity()); llvm::Constant *C = llvm::UndefValue::get(Ty); Elements.push_back(C); assert(getAlignment(C) == CharUnits::One() && "Padding must have 1 byte alignment!"); NextFieldOffsetInChars += getSizeInChars(C); } void ConstStructBuilder::AppendTailPadding(CharUnits RecordSize) { assert(NextFieldOffsetInChars <= RecordSize && "Size mismatch!"); AppendPadding(RecordSize - NextFieldOffsetInChars); } void ConstStructBuilder::ConvertStructToPacked() { SmallVector PackedElements; CharUnits ElementOffsetInChars = CharUnits::Zero(); for (unsigned i = 0, e = Elements.size(); i != e; ++i) { llvm::Constant *C = Elements[i]; CharUnits ElementAlign = CharUnits::fromQuantity( CGM.getDataLayout().getABITypeAlignment(C->getType())); CharUnits AlignedElementOffsetInChars = ElementOffsetInChars.RoundUpToAlignment(ElementAlign); if (AlignedElementOffsetInChars > ElementOffsetInChars) { // We need some padding. CharUnits NumChars = AlignedElementOffsetInChars - ElementOffsetInChars; llvm::Type *Ty = CGM.Int8Ty; if (NumChars > CharUnits::One()) Ty = llvm::ArrayType::get(Ty, NumChars.getQuantity()); llvm::Constant *Padding = llvm::UndefValue::get(Ty); PackedElements.push_back(Padding); ElementOffsetInChars += getSizeInChars(Padding); } PackedElements.push_back(C); ElementOffsetInChars += getSizeInChars(C); } assert(ElementOffsetInChars == NextFieldOffsetInChars && "Packing the struct changed its size!"); Elements.swap(PackedElements); LLVMStructAlignment = CharUnits::One(); Packed = true; } bool ConstStructBuilder::Build(InitListExpr *ILE) { RecordDecl *RD = ILE->getType()->getAs()->getDecl(); const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); unsigned FieldNo = 0; unsigned ElementNo = 0; for (RecordDecl::field_iterator Field = RD->field_begin(), FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) { // If this is a union, skip all the fields that aren't being initialized. if (RD->isUnion() && ILE->getInitializedFieldInUnion() != *Field) continue; // Don't emit anonymous bitfields, they just affect layout. if (Field->isUnnamedBitfield()) continue; // Get the initializer. A struct can include fields without initializers, // we just use explicit null values for them. llvm::Constant *EltInit; if (ElementNo < ILE->getNumInits()) EltInit = CGM.EmitConstantExpr(ILE->getInit(ElementNo++), Field->getType(), CGF); else EltInit = CGM.EmitNullConstant(Field->getType()); if (!EltInit) return false; if (!Field->isBitField()) { // Handle non-bitfield members. AppendField(*Field, Layout.getFieldOffset(FieldNo), EltInit); } else { // Otherwise we have a bitfield. AppendBitField(*Field, Layout.getFieldOffset(FieldNo), cast(EltInit)); } } return true; } namespace { struct BaseInfo { BaseInfo(const CXXRecordDecl *Decl, CharUnits Offset, unsigned Index) : Decl(Decl), Offset(Offset), Index(Index) { } const CXXRecordDecl *Decl; CharUnits Offset; unsigned Index; bool operator<(const BaseInfo &O) const { return Offset < O.Offset; } }; } void ConstStructBuilder::Build(const APValue &Val, const RecordDecl *RD, bool IsPrimaryBase, const CXXRecordDecl *VTableClass, CharUnits Offset) { const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); if (const CXXRecordDecl *CD = dyn_cast(RD)) { // Add a vtable pointer, if we need one and it hasn't already been added. if (CD->isDynamicClass() && !IsPrimaryBase) { llvm::Constant *VTableAddressPoint = CGM.getCXXABI().getVTableAddressPointForConstExpr( BaseSubobject(CD, Offset), VTableClass); AppendBytes(Offset, VTableAddressPoint); } // Accumulate and sort bases, in order to visit them in address order, which // may not be the same as declaration order. SmallVector Bases; Bases.reserve(CD->getNumBases()); unsigned BaseNo = 0; for (CXXRecordDecl::base_class_const_iterator Base = CD->bases_begin(), BaseEnd = CD->bases_end(); Base != BaseEnd; ++Base, ++BaseNo) { assert(!Base->isVirtual() && "should not have virtual bases here"); const CXXRecordDecl *BD = Base->getType()->getAsCXXRecordDecl(); CharUnits BaseOffset = Layout.getBaseClassOffset(BD); Bases.push_back(BaseInfo(BD, BaseOffset, BaseNo)); } std::stable_sort(Bases.begin(), Bases.end()); for (unsigned I = 0, N = Bases.size(); I != N; ++I) { BaseInfo &Base = Bases[I]; bool IsPrimaryBase = Layout.getPrimaryBase() == Base.Decl; Build(Val.getStructBase(Base.Index), Base.Decl, IsPrimaryBase, VTableClass, Offset + Base.Offset); } } unsigned FieldNo = 0; uint64_t OffsetBits = CGM.getContext().toBits(Offset); for (RecordDecl::field_iterator Field = RD->field_begin(), FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) { // If this is a union, skip all the fields that aren't being initialized. if (RD->isUnion() && Val.getUnionField() != *Field) continue; // Don't emit anonymous bitfields, they just affect layout. if (Field->isUnnamedBitfield()) continue; // Emit the value of the initializer. const APValue &FieldValue = RD->isUnion() ? Val.getUnionValue() : Val.getStructField(FieldNo); llvm::Constant *EltInit = CGM.EmitConstantValueForMemory(FieldValue, Field->getType(), CGF); assert(EltInit && "EmitConstantValue can't fail"); if (!Field->isBitField()) { // Handle non-bitfield members. AppendField(*Field, Layout.getFieldOffset(FieldNo) + OffsetBits, EltInit); } else { // Otherwise we have a bitfield. AppendBitField(*Field, Layout.getFieldOffset(FieldNo) + OffsetBits, cast(EltInit)); } } } llvm::Constant *ConstStructBuilder::Finalize(QualType Ty) { RecordDecl *RD = Ty->getAs()->getDecl(); const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); CharUnits LayoutSizeInChars = Layout.getSize(); if (NextFieldOffsetInChars > LayoutSizeInChars) { // If the struct is bigger than the size of the record type, // we must have a flexible array member at the end. assert(RD->hasFlexibleArrayMember() && "Must have flexible array member if struct is bigger than type!"); // No tail padding is necessary. } else { // Append tail padding if necessary. AppendTailPadding(LayoutSizeInChars); CharUnits LLVMSizeInChars = NextFieldOffsetInChars.RoundUpToAlignment(LLVMStructAlignment); // Check if we need to convert the struct to a packed struct. if (NextFieldOffsetInChars <= LayoutSizeInChars && LLVMSizeInChars > LayoutSizeInChars) { assert(!Packed && "Size mismatch!"); ConvertStructToPacked(); assert(NextFieldOffsetInChars <= LayoutSizeInChars && "Converting to packed did not help!"); } assert(LayoutSizeInChars == NextFieldOffsetInChars && "Tail padding mismatch!"); } // Pick the type to use. If the type is layout identical to the ConvertType // type then use it, otherwise use whatever the builder produced for us. llvm::StructType *STy = llvm::ConstantStruct::getTypeForElements(CGM.getLLVMContext(), Elements, Packed); llvm::Type *ValTy = CGM.getTypes().ConvertType(Ty); if (llvm::StructType *ValSTy = dyn_cast(ValTy)) { if (ValSTy->isLayoutIdentical(STy)) STy = ValSTy; } llvm::Constant *Result = llvm::ConstantStruct::get(STy, Elements); assert(NextFieldOffsetInChars.RoundUpToAlignment(getAlignment(Result)) == getSizeInChars(Result) && "Size mismatch!"); return Result; } llvm::Constant *ConstStructBuilder::BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, InitListExpr *ILE) { ConstStructBuilder Builder(CGM, CGF); if (!Builder.Build(ILE)) return 0; return Builder.Finalize(ILE->getType()); } llvm::Constant *ConstStructBuilder::BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF, const APValue &Val, QualType ValTy) { ConstStructBuilder Builder(CGM, CGF); const RecordDecl *RD = ValTy->castAs()->getDecl(); const CXXRecordDecl *CD = dyn_cast(RD); Builder.Build(Val, RD, false, CD, CharUnits::Zero()); return Builder.Finalize(ValTy); } //===----------------------------------------------------------------------===// // ConstExprEmitter //===----------------------------------------------------------------------===// /// This class only needs to handle two cases: /// 1) Literals (this is used by APValue emission to emit literals). /// 2) Arrays, structs and unions (outside C++11 mode, we don't currently /// constant fold these types). class ConstExprEmitter : public StmtVisitor { CodeGenModule &CGM; CodeGenFunction *CGF; llvm::LLVMContext &VMContext; public: ConstExprEmitter(CodeGenModule &cgm, CodeGenFunction *cgf) : CGM(cgm), CGF(cgf), VMContext(cgm.getLLVMContext()) { } //===--------------------------------------------------------------------===// // Visitor Methods //===--------------------------------------------------------------------===// llvm::Constant *VisitStmt(Stmt *S) { return 0; } llvm::Constant *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } llvm::Constant * VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE) { return Visit(PE->getReplacement()); } llvm::Constant *VisitGenericSelectionExpr(GenericSelectionExpr *GE) { return Visit(GE->getResultExpr()); } llvm::Constant *VisitChooseExpr(ChooseExpr *CE) { return Visit(CE->getChosenSubExpr()); } llvm::Constant *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { return Visit(E->getInitializer()); } llvm::Constant *VisitCastExpr(CastExpr* E) { Expr *subExpr = E->getSubExpr(); llvm::Constant *C = CGM.EmitConstantExpr(subExpr, subExpr->getType(), CGF); if (!C) return 0; llvm::Type *destType = ConvertType(E->getType()); switch (E->getCastKind()) { case CK_ToUnion: { // GCC cast to union extension assert(E->getType()->isUnionType() && "Destination type is not union type!"); // Build a struct with the union sub-element as the first member, // and padded to the appropriate size SmallVector Elts; SmallVector Types; Elts.push_back(C); Types.push_back(C->getType()); unsigned CurSize = CGM.getDataLayout().getTypeAllocSize(C->getType()); unsigned TotalSize = CGM.getDataLayout().getTypeAllocSize(destType); assert(CurSize <= TotalSize && "Union size mismatch!"); if (unsigned NumPadBytes = TotalSize - CurSize) { llvm::Type *Ty = CGM.Int8Ty; if (NumPadBytes > 1) Ty = llvm::ArrayType::get(Ty, NumPadBytes); Elts.push_back(llvm::UndefValue::get(Ty)); Types.push_back(Ty); } llvm::StructType* STy = llvm::StructType::get(C->getType()->getContext(), Types, false); return llvm::ConstantStruct::get(STy, Elts); } case CK_AddressSpaceConversion: return llvm::ConstantExpr::getAddrSpaceCast(C, destType); case CK_LValueToRValue: case CK_AtomicToNonAtomic: case CK_NonAtomicToAtomic: case CK_NoOp: case CK_ConstructorConversion: return C; case CK_Dependent: llvm_unreachable("saw dependent cast!"); case CK_BuiltinFnToFnPtr: llvm_unreachable("builtin functions are handled elsewhere"); case CK_ReinterpretMemberPointer: case CK_DerivedToBaseMemberPointer: case CK_BaseToDerivedMemberPointer: return CGM.getCXXABI().EmitMemberPointerConversion(E, C); // These will never be supported. case CK_ObjCObjectLValueCast: case CK_ARCProduceObject: case CK_ARCConsumeObject: case CK_ARCReclaimReturnedObject: case CK_ARCExtendBlockObject: case CK_CopyAndAutoreleaseBlockObject: return 0; // These don't need to be handled here because Evaluate knows how to // evaluate them in the cases where they can be folded. case CK_BitCast: case CK_ToVoid: case CK_Dynamic: case CK_LValueBitCast: case CK_NullToMemberPointer: case CK_UserDefinedConversion: case CK_CPointerToObjCPointerCast: case CK_BlockPointerToObjCPointerCast: case CK_AnyPointerToBlockPointerCast: case CK_ArrayToPointerDecay: case CK_FunctionToPointerDecay: case CK_BaseToDerived: case CK_DerivedToBase: case CK_UncheckedDerivedToBase: case CK_MemberPointerToBoolean: case CK_VectorSplat: case CK_FloatingRealToComplex: case CK_FloatingComplexToReal: case CK_FloatingComplexToBoolean: case CK_FloatingComplexCast: case CK_FloatingComplexToIntegralComplex: case CK_IntegralRealToComplex: case CK_IntegralComplexToReal: case CK_IntegralComplexToBoolean: case CK_IntegralComplexCast: case CK_IntegralComplexToFloatingComplex: case CK_PointerToIntegral: case CK_PointerToBoolean: case CK_NullToPointer: case CK_IntegralCast: case CK_IntegralToPointer: case CK_IntegralToBoolean: case CK_IntegralToFloating: case CK_FloatingToIntegral: case CK_FloatingToBoolean: case CK_FloatingCast: case CK_ZeroToOCLEvent: return 0; } llvm_unreachable("Invalid CastKind"); } llvm::Constant *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { return Visit(DAE->getExpr()); } llvm::Constant *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) { // No need for a DefaultInitExprScope: we don't handle 'this' in a // constant expression. return Visit(DIE->getExpr()); } llvm::Constant *VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E) { return Visit(E->GetTemporaryExpr()); } llvm::Constant *EmitArrayInitialization(InitListExpr *ILE) { if (ILE->isStringLiteralInit()) return Visit(ILE->getInit(0)); llvm::ArrayType *AType = cast(ConvertType(ILE->getType())); llvm::Type *ElemTy = AType->getElementType(); unsigned NumInitElements = ILE->getNumInits(); unsigned NumElements = AType->getNumElements(); // Initialising an array requires us to automatically // initialise any elements that have not been initialised explicitly unsigned NumInitableElts = std::min(NumInitElements, NumElements); // Copy initializer elements. std::vector Elts; Elts.reserve(NumInitableElts + NumElements); bool RewriteType = false; for (unsigned i = 0; i < NumInitableElts; ++i) { Expr *Init = ILE->getInit(i); llvm::Constant *C = CGM.EmitConstantExpr(Init, Init->getType(), CGF); if (!C) return 0; RewriteType |= (C->getType() != ElemTy); Elts.push_back(C); } // Initialize remaining array elements. // FIXME: This doesn't handle member pointers correctly! llvm::Constant *fillC; if (Expr *filler = ILE->getArrayFiller()) fillC = CGM.EmitConstantExpr(filler, filler->getType(), CGF); else fillC = llvm::Constant::getNullValue(ElemTy); if (!fillC) return 0; RewriteType |= (fillC->getType() != ElemTy); Elts.resize(NumElements, fillC); if (RewriteType) { // FIXME: Try to avoid packing the array std::vector Types; Types.reserve(NumInitableElts + NumElements); for (unsigned i = 0, e = Elts.size(); i < e; ++i) Types.push_back(Elts[i]->getType()); llvm::StructType *SType = llvm::StructType::get(AType->getContext(), Types, true); return llvm::ConstantStruct::get(SType, Elts); } return llvm::ConstantArray::get(AType, Elts); } llvm::Constant *EmitRecordInitialization(InitListExpr *ILE) { return ConstStructBuilder::BuildStruct(CGM, CGF, ILE); } llvm::Constant *VisitImplicitValueInitExpr(ImplicitValueInitExpr* E) { return CGM.EmitNullConstant(E->getType()); } llvm::Constant *VisitInitListExpr(InitListExpr *ILE) { if (ILE->getType()->isArrayType()) return EmitArrayInitialization(ILE); if (ILE->getType()->isRecordType()) return EmitRecordInitialization(ILE); return 0; } llvm::Constant *VisitCXXConstructExpr(CXXConstructExpr *E) { if (!E->getConstructor()->isTrivial()) return 0; QualType Ty = E->getType(); // FIXME: We should not have to call getBaseElementType here. const RecordType *RT = CGM.getContext().getBaseElementType(Ty)->getAs(); const CXXRecordDecl *RD = cast(RT->getDecl()); // If the class doesn't have a trivial destructor, we can't emit it as a // constant expr. if (!RD->hasTrivialDestructor()) return 0; // Only copy and default constructors can be trivial. if (E->getNumArgs()) { assert(E->getNumArgs() == 1 && "trivial ctor with > 1 argument"); assert(E->getConstructor()->isCopyOrMoveConstructor() && "trivial ctor has argument but isn't a copy/move ctor"); Expr *Arg = E->getArg(0); assert(CGM.getContext().hasSameUnqualifiedType(Ty, Arg->getType()) && "argument to copy ctor is of wrong type"); return Visit(Arg); } return CGM.EmitNullConstant(Ty); } llvm::Constant *VisitStringLiteral(StringLiteral *E) { return CGM.GetConstantArrayFromStringLiteral(E); } llvm::Constant *VisitObjCEncodeExpr(ObjCEncodeExpr *E) { // This must be an @@encode initializing an array in a static initializer. // Don't emit it as the address of the string, emit the string data itself // as an inline array. std::string Str; CGM.getContext().getObjCEncodingForType(E->getEncodedType(), Str); const ConstantArrayType *CAT = cast(E->getType()); // Resize the string to the right size, adding zeros at the end, or // truncating as needed. Str.resize(CAT->getSize().getZExtValue(), '\0'); return llvm::ConstantDataArray::getString(VMContext, Str, false); } llvm::Constant *VisitUnaryExtension(const UnaryOperator *E) { return Visit(E->getSubExpr()); } // Utility methods llvm::Type *ConvertType(QualType T) { return CGM.getTypes().ConvertType(T); } public: llvm::Constant *EmitLValue(APValue::LValueBase LVBase) { if (const ValueDecl *Decl = LVBase.dyn_cast()) { if (Decl->hasAttr()) return CGM.GetWeakRefReference(Decl); if (const FunctionDecl *FD = dyn_cast(Decl)) return CGM.GetAddrOfFunction(FD); if (const VarDecl* VD = dyn_cast(Decl)) { // We can never refer to a variable with local storage. if (!VD->hasLocalStorage()) { if (VD->isFileVarDecl() || VD->hasExternalStorage()) return CGM.GetAddrOfGlobalVar(VD); else if (VD->isLocalVarDecl()) return CGM.getStaticLocalDeclAddress(VD); } } return 0; } Expr *E = const_cast(LVBase.get()); switch (E->getStmtClass()) { default: break; case Expr::CompoundLiteralExprClass: { // Note that due to the nature of compound literals, this is guaranteed // to be the only use of the variable, so we just generate it here. CompoundLiteralExpr *CLE = cast(E); llvm::Constant* C = CGM.EmitConstantExpr(CLE->getInitializer(), CLE->getType(), CGF); // FIXME: "Leaked" on failure. if (C) C = new llvm::GlobalVariable(CGM.getModule(), C->getType(), E->getType().isConstant(CGM.getContext()), llvm::GlobalValue::InternalLinkage, C, ".compoundliteral", 0, llvm::GlobalVariable::NotThreadLocal, CGM.getContext().getTargetAddressSpace(E->getType())); return C; } case Expr::StringLiteralClass: return CGM.GetAddrOfConstantStringFromLiteral(cast(E)); case Expr::ObjCEncodeExprClass: return CGM.GetAddrOfConstantStringFromObjCEncode(cast(E)); case Expr::ObjCStringLiteralClass: { ObjCStringLiteral* SL = cast(E); llvm::Constant *C = CGM.getObjCRuntime().GenerateConstantString(SL->getString()); return llvm::ConstantExpr::getBitCast(C, ConvertType(E->getType())); } case Expr::PredefinedExprClass: { unsigned Type = cast(E)->getIdentType(); if (CGF) { LValue Res = CGF->EmitPredefinedLValue(cast(E)); return cast(Res.getAddress()); } else if (Type == PredefinedExpr::PrettyFunction) { return CGM.GetAddrOfConstantCString("top level", ".tmp"); } return CGM.GetAddrOfConstantCString("", ".tmp"); } case Expr::AddrLabelExprClass: { assert(CGF && "Invalid address of label expression outside function."); llvm::Constant *Ptr = CGF->GetAddrOfLabel(cast(E)->getLabel()); return llvm::ConstantExpr::getBitCast(Ptr, ConvertType(E->getType())); } case Expr::CallExprClass: { CallExpr* CE = cast(E); unsigned builtin = CE->getBuiltinCallee(); if (builtin != Builtin::BI__builtin___CFStringMakeConstantString && builtin != Builtin::BI__builtin___NSStringMakeConstantString) break; const Expr *Arg = CE->getArg(0)->IgnoreParenCasts(); const StringLiteral *Literal = cast(Arg); if (builtin == Builtin::BI__builtin___NSStringMakeConstantString) { return CGM.getObjCRuntime().GenerateConstantString(Literal); } // FIXME: need to deal with UCN conversion issues. return CGM.GetAddrOfConstantCFString(Literal); } case Expr::BlockExprClass: { std::string FunctionName; if (CGF) FunctionName = CGF->CurFn->getName(); else FunctionName = "global"; return CGM.GetAddrOfGlobalBlock(cast(E), FunctionName.c_str()); } case Expr::CXXTypeidExprClass: { CXXTypeidExpr *Typeid = cast(E); QualType T; if (Typeid->isTypeOperand()) T = Typeid->getTypeOperand(CGM.getContext()); else T = Typeid->getExprOperand()->getType(); return CGM.GetAddrOfRTTIDescriptor(T); } case Expr::CXXUuidofExprClass: { return CGM.GetAddrOfUuidDescriptor(cast(E)); } case Expr::MaterializeTemporaryExprClass: { MaterializeTemporaryExpr *MTE = cast(E); assert(MTE->getStorageDuration() == SD_Static); SmallVector CommaLHSs; SmallVector Adjustments; const Expr *Inner = MTE->GetTemporaryExpr() ->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); return CGM.GetAddrOfGlobalTemporary(MTE, Inner); } } return 0; } }; } // end anonymous namespace. llvm::Constant *CodeGenModule::EmitConstantInit(const VarDecl &D, CodeGenFunction *CGF) { // Make a quick check if variable can be default NULL initialized // and avoid going through rest of code which may do, for c++11, // initialization of memory to all NULLs. if (!D.hasLocalStorage()) { QualType Ty = D.getType(); if (Ty->isArrayType()) Ty = Context.getBaseElementType(Ty); if (Ty->isRecordType()) if (const CXXConstructExpr *E = dyn_cast_or_null(D.getInit())) { const CXXConstructorDecl *CD = E->getConstructor(); if (CD->isTrivial() && CD->isDefaultConstructor()) return EmitNullConstant(D.getType()); } } if (const APValue *Value = D.evaluateValue()) return EmitConstantValueForMemory(*Value, D.getType(), CGF); // FIXME: Implement C++11 [basic.start.init]p2: if the initializer of a // reference is a constant expression, and the reference binds to a temporary, // then constant initialization is performed. ConstExprEmitter will // incorrectly emit a prvalue constant in this case, and the calling code // interprets that as the (pointer) value of the reference, rather than the // desired value of the referee. if (D.getType()->isReferenceType()) return 0; const Expr *E = D.getInit(); assert(E && "No initializer to emit"); llvm::Constant* C = ConstExprEmitter(*this, CGF).Visit(const_cast(E)); if (C && C->getType()->isIntegerTy(1)) { llvm::Type *BoolTy = getTypes().ConvertTypeForMem(E->getType()); C = llvm::ConstantExpr::getZExt(C, BoolTy); } return C; } llvm::Constant *CodeGenModule::EmitConstantExpr(const Expr *E, QualType DestType, CodeGenFunction *CGF) { Expr::EvalResult Result; bool Success = false; if (DestType->isReferenceType()) Success = E->EvaluateAsLValue(Result, Context); else Success = E->EvaluateAsRValue(Result, Context); llvm::Constant *C = 0; if (Success && !Result.HasSideEffects) C = EmitConstantValue(Result.Val, DestType, CGF); else C = ConstExprEmitter(*this, CGF).Visit(const_cast(E)); if (C && C->getType()->isIntegerTy(1)) { llvm::Type *BoolTy = getTypes().ConvertTypeForMem(E->getType()); C = llvm::ConstantExpr::getZExt(C, BoolTy); } return C; } llvm::Constant *CodeGenModule::EmitConstantValue(const APValue &Value, QualType DestType, CodeGenFunction *CGF) { switch (Value.getKind()) { case APValue::Uninitialized: llvm_unreachable("Constant expressions should be initialized."); case APValue::LValue: { llvm::Type *DestTy = getTypes().ConvertTypeForMem(DestType); llvm::Constant *Offset = llvm::ConstantInt::get(Int64Ty, Value.getLValueOffset().getQuantity()); llvm::Constant *C; if (APValue::LValueBase LVBase = Value.getLValueBase()) { // An array can be represented as an lvalue referring to the base. if (isa(DestTy)) { assert(Offset->isNullValue() && "offset on array initializer"); return ConstExprEmitter(*this, CGF).Visit( const_cast(LVBase.get())); } C = ConstExprEmitter(*this, CGF).EmitLValue(LVBase); // Apply offset if necessary. if (!Offset->isNullValue()) { llvm::Constant *Casted = llvm::ConstantExpr::getBitCast(C, Int8PtrTy); Casted = llvm::ConstantExpr::getGetElementPtr(Casted, Offset); C = llvm::ConstantExpr::getPointerCast(Casted, C->getType()); } // Convert to the appropriate type; this could be an lvalue for // an integer. if (isa(DestTy)) return llvm::ConstantExpr::getPointerCast(C, DestTy); return llvm::ConstantExpr::getPtrToInt(C, DestTy); } else { C = Offset; // Convert to the appropriate type; this could be an lvalue for // an integer. if (isa(DestTy)) return llvm::ConstantExpr::getIntToPtr(C, DestTy); // If the types don't match this should only be a truncate. if (C->getType() != DestTy) return llvm::ConstantExpr::getTrunc(C, DestTy); return C; } } case APValue::Int: return llvm::ConstantInt::get(VMContext, Value.getInt()); case APValue::ComplexInt: { llvm::Constant *Complex[2]; Complex[0] = llvm::ConstantInt::get(VMContext, Value.getComplexIntReal()); Complex[1] = llvm::ConstantInt::get(VMContext, Value.getComplexIntImag()); // FIXME: the target may want to specify that this is packed. llvm::StructType *STy = llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType(), NULL); return llvm::ConstantStruct::get(STy, Complex); } case APValue::Float: { const llvm::APFloat &Init = Value.getFloat(); if (&Init.getSemantics() == &llvm::APFloat::IEEEhalf && !Context.getLangOpts().NativeHalfType) return llvm::ConstantInt::get(VMContext, Init.bitcastToAPInt()); else return llvm::ConstantFP::get(VMContext, Init); } case APValue::ComplexFloat: { llvm::Constant *Complex[2]; Complex[0] = llvm::ConstantFP::get(VMContext, Value.getComplexFloatReal()); Complex[1] = llvm::ConstantFP::get(VMContext, Value.getComplexFloatImag()); // FIXME: the target may want to specify that this is packed. llvm::StructType *STy = llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType(), NULL); return llvm::ConstantStruct::get(STy, Complex); } case APValue::Vector: { SmallVector Inits; unsigned NumElts = Value.getVectorLength(); for (unsigned i = 0; i != NumElts; ++i) { const APValue &Elt = Value.getVectorElt(i); if (Elt.isInt()) Inits.push_back(llvm::ConstantInt::get(VMContext, Elt.getInt())); else Inits.push_back(llvm::ConstantFP::get(VMContext, Elt.getFloat())); } return llvm::ConstantVector::get(Inits); } case APValue::AddrLabelDiff: { const AddrLabelExpr *LHSExpr = Value.getAddrLabelDiffLHS(); const AddrLabelExpr *RHSExpr = Value.getAddrLabelDiffRHS(); llvm::Constant *LHS = EmitConstantExpr(LHSExpr, LHSExpr->getType(), CGF); llvm::Constant *RHS = EmitConstantExpr(RHSExpr, RHSExpr->getType(), CGF); // Compute difference llvm::Type *ResultType = getTypes().ConvertType(DestType); LHS = llvm::ConstantExpr::getPtrToInt(LHS, IntPtrTy); RHS = llvm::ConstantExpr::getPtrToInt(RHS, IntPtrTy); llvm::Constant *AddrLabelDiff = llvm::ConstantExpr::getSub(LHS, RHS); // LLVM is a bit sensitive about the exact format of the // address-of-label difference; make sure to truncate after // the subtraction. return llvm::ConstantExpr::getTruncOrBitCast(AddrLabelDiff, ResultType); } case APValue::Struct: case APValue::Union: return ConstStructBuilder::BuildStruct(*this, CGF, Value, DestType); case APValue::Array: { const ArrayType *CAT = Context.getAsArrayType(DestType); unsigned NumElements = Value.getArraySize(); unsigned NumInitElts = Value.getArrayInitializedElts(); std::vector Elts; Elts.reserve(NumElements); // Emit array filler, if there is one. llvm::Constant *Filler = 0; if (Value.hasArrayFiller()) Filler = EmitConstantValueForMemory(Value.getArrayFiller(), CAT->getElementType(), CGF); // Emit initializer elements. llvm::Type *CommonElementType = 0; for (unsigned I = 0; I < NumElements; ++I) { llvm::Constant *C = Filler; if (I < NumInitElts) C = EmitConstantValueForMemory(Value.getArrayInitializedElt(I), CAT->getElementType(), CGF); else assert(Filler && "Missing filler for implicit elements of initializer"); if (I == 0) CommonElementType = C->getType(); else if (C->getType() != CommonElementType) CommonElementType = 0; Elts.push_back(C); } if (!CommonElementType) { // FIXME: Try to avoid packing the array std::vector Types; Types.reserve(NumElements); for (unsigned i = 0, e = Elts.size(); i < e; ++i) Types.push_back(Elts[i]->getType()); llvm::StructType *SType = llvm::StructType::get(VMContext, Types, true); return llvm::ConstantStruct::get(SType, Elts); } llvm::ArrayType *AType = llvm::ArrayType::get(CommonElementType, NumElements); return llvm::ConstantArray::get(AType, Elts); } case APValue::MemberPointer: return getCXXABI().EmitMemberPointer(Value, DestType); } llvm_unreachable("Unknown APValue kind"); } llvm::Constant * CodeGenModule::EmitConstantValueForMemory(const APValue &Value, QualType DestType, CodeGenFunction *CGF) { llvm::Constant *C = EmitConstantValue(Value, DestType, CGF); if (C->getType()->isIntegerTy(1)) { llvm::Type *BoolTy = getTypes().ConvertTypeForMem(DestType); C = llvm::ConstantExpr::getZExt(C, BoolTy); } return C; } llvm::Constant * CodeGenModule::GetAddrOfConstantCompoundLiteral(const CompoundLiteralExpr *E) { assert(E->isFileScope() && "not a file-scope compound literal expr"); return ConstExprEmitter(*this, 0).EmitLValue(E); } llvm::Constant * CodeGenModule::getMemberPointerConstant(const UnaryOperator *uo) { // Member pointer constants always have a very particular form. const MemberPointerType *type = cast(uo->getType()); const ValueDecl *decl = cast(uo->getSubExpr())->getDecl(); // A member function pointer. if (const CXXMethodDecl *method = dyn_cast(decl)) return getCXXABI().EmitMemberPointer(method); // Otherwise, a member data pointer. uint64_t fieldOffset = getContext().getFieldOffset(decl); CharUnits chars = getContext().toCharUnitsFromBits((int64_t) fieldOffset); return getCXXABI().EmitMemberDataPointer(type, chars); } static void FillInNullDataMemberPointers(CodeGenModule &CGM, QualType T, SmallVectorImpl &Elements, uint64_t StartOffset) { assert(StartOffset % CGM.getContext().getCharWidth() == 0 && "StartOffset not byte aligned!"); if (CGM.getTypes().isZeroInitializable(T)) return; if (const ConstantArrayType *CAT = CGM.getContext().getAsConstantArrayType(T)) { QualType ElementTy = CAT->getElementType(); uint64_t ElementSize = CGM.getContext().getTypeSize(ElementTy); for (uint64_t I = 0, E = CAT->getSize().getZExtValue(); I != E; ++I) { FillInNullDataMemberPointers(CGM, ElementTy, Elements, StartOffset + I * ElementSize); } } else if (const RecordType *RT = T->getAs()) { const CXXRecordDecl *RD = cast(RT->getDecl()); const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); // Go through all bases and fill in any null pointer to data members. for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(), E = RD->bases_end(); I != E; ++I) { if (I->isVirtual()) { // Ignore virtual bases. continue; } const CXXRecordDecl *BaseDecl = cast(I->getType()->getAs()->getDecl()); // Ignore empty bases. if (BaseDecl->isEmpty()) continue; // Ignore bases that don't have any pointer to data members. if (CGM.getTypes().isZeroInitializable(BaseDecl)) continue; uint64_t BaseOffset = CGM.getContext().toBits(Layout.getBaseClassOffset(BaseDecl)); FillInNullDataMemberPointers(CGM, I->getType(), Elements, StartOffset + BaseOffset); } // Visit all fields. unsigned FieldNo = 0; for (RecordDecl::field_iterator I = RD->field_begin(), E = RD->field_end(); I != E; ++I, ++FieldNo) { QualType FieldType = I->getType(); if (CGM.getTypes().isZeroInitializable(FieldType)) continue; uint64_t FieldOffset = StartOffset + Layout.getFieldOffset(FieldNo); FillInNullDataMemberPointers(CGM, FieldType, Elements, FieldOffset); } } else { assert(T->isMemberPointerType() && "Should only see member pointers here!"); assert(!T->getAs()->getPointeeType()->isFunctionType() && "Should only see pointers to data members here!"); CharUnits StartIndex = CGM.getContext().toCharUnitsFromBits(StartOffset); CharUnits EndIndex = StartIndex + CGM.getContext().getTypeSizeInChars(T); // FIXME: hardcodes Itanium member pointer representation! llvm::Constant *NegativeOne = llvm::ConstantInt::get(CGM.Int8Ty, -1ULL, /*isSigned*/true); // Fill in the null data member pointer. for (CharUnits I = StartIndex; I != EndIndex; ++I) Elements[I.getQuantity()] = NegativeOne; } } static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM, llvm::Type *baseType, const CXXRecordDecl *base); static llvm::Constant *EmitNullConstant(CodeGenModule &CGM, const CXXRecordDecl *record, bool asCompleteObject) { const CGRecordLayout &layout = CGM.getTypes().getCGRecordLayout(record); llvm::StructType *structure = (asCompleteObject ? layout.getLLVMType() : layout.getBaseSubobjectLLVMType()); unsigned numElements = structure->getNumElements(); std::vector elements(numElements); // Fill in all the bases. for (CXXRecordDecl::base_class_const_iterator I = record->bases_begin(), E = record->bases_end(); I != E; ++I) { if (I->isVirtual()) { // Ignore virtual bases; if we're laying out for a complete // object, we'll lay these out later. continue; } const CXXRecordDecl *base = cast(I->getType()->castAs()->getDecl()); // Ignore empty bases. if (base->isEmpty()) continue; unsigned fieldIndex = layout.getNonVirtualBaseLLVMFieldNo(base); llvm::Type *baseType = structure->getElementType(fieldIndex); elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base); } // Fill in all the fields. for (RecordDecl::field_iterator I = record->field_begin(), E = record->field_end(); I != E; ++I) { const FieldDecl *field = *I; // Fill in non-bitfields. (Bitfields always use a zero pattern, which we // will fill in later.) if (!field->isBitField()) { unsigned fieldIndex = layout.getLLVMFieldNo(field); elements[fieldIndex] = CGM.EmitNullConstant(field->getType()); } // For unions, stop after the first named field. if (record->isUnion() && field->getDeclName()) break; } // Fill in the virtual bases, if we're working with the complete object. if (asCompleteObject) { for (CXXRecordDecl::base_class_const_iterator I = record->vbases_begin(), E = record->vbases_end(); I != E; ++I) { const CXXRecordDecl *base = cast(I->getType()->castAs()->getDecl()); // Ignore empty bases. if (base->isEmpty()) continue; unsigned fieldIndex = layout.getVirtualBaseIndex(base); // We might have already laid this field out. if (elements[fieldIndex]) continue; llvm::Type *baseType = structure->getElementType(fieldIndex); elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base); } } // Now go through all other fields and zero them out. for (unsigned i = 0; i != numElements; ++i) { if (!elements[i]) elements[i] = llvm::Constant::getNullValue(structure->getElementType(i)); } return llvm::ConstantStruct::get(structure, elements); } /// Emit the null constant for a base subobject. static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM, llvm::Type *baseType, const CXXRecordDecl *base) { const CGRecordLayout &baseLayout = CGM.getTypes().getCGRecordLayout(base); // Just zero out bases that don't have any pointer to data members. if (baseLayout.isZeroInitializableAsBase()) return llvm::Constant::getNullValue(baseType); // If the base type is a struct, we can just use its null constant. if (isa(baseType)) { return EmitNullConstant(CGM, base, /*complete*/ false); } // Otherwise, some bases are represented as arrays of i8 if the size // of the base is smaller than its corresponding LLVM type. Figure // out how many elements this base array has. llvm::ArrayType *baseArrayType = cast(baseType); unsigned numBaseElements = baseArrayType->getNumElements(); // Fill in null data member pointers. SmallVector baseElements(numBaseElements); FillInNullDataMemberPointers(CGM, CGM.getContext().getTypeDeclType(base), baseElements, 0); // Now go through all other elements and zero them out. if (numBaseElements) { llvm::Constant *i8_zero = llvm::Constant::getNullValue(CGM.Int8Ty); for (unsigned i = 0; i != numBaseElements; ++i) { if (!baseElements[i]) baseElements[i] = i8_zero; } } return llvm::ConstantArray::get(baseArrayType, baseElements); } llvm::Constant *CodeGenModule::EmitNullConstant(QualType T) { if (getTypes().isZeroInitializable(T)) return llvm::Constant::getNullValue(getTypes().ConvertTypeForMem(T)); if (const ConstantArrayType *CAT = Context.getAsConstantArrayType(T)) { llvm::ArrayType *ATy = cast(getTypes().ConvertTypeForMem(T)); QualType ElementTy = CAT->getElementType(); llvm::Constant *Element = EmitNullConstant(ElementTy); unsigned NumElements = CAT->getSize().getZExtValue(); if (Element->isNullValue()) return llvm::ConstantAggregateZero::get(ATy); SmallVector Array(NumElements, Element); return llvm::ConstantArray::get(ATy, Array); } if (const RecordType *RT = T->getAs()) { const CXXRecordDecl *RD = cast(RT->getDecl()); return ::EmitNullConstant(*this, RD, /*complete object*/ true); } assert(T->isMemberPointerType() && "Should only see member pointers here!"); assert(!T->getAs()->getPointeeType()->isFunctionType() && "Should only see pointers to data members here!"); // Itanium C++ ABI 2.3: // A NULL pointer is represented as -1. return getCXXABI().EmitNullMemberPointer(T->castAs()); } llvm::Constant * CodeGenModule::EmitNullConstantForBase(const CXXRecordDecl *Record) { return ::EmitNullConstant(*this, Record, false); } @