X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTarget%2FTargetLoweringObjectFile.cpp;h=19b5e2a0f978bd4095be39f9e17402f949798cd3;hb=4aad126e378dba040c793d735e802e3be6aeccbe;hp=421f1e8fa838dbe13695e57233858752a2e704ab;hpb=98cdab53c302a2d6686fa428c0e896b1fb195311;p=oota-llvm.git diff --git a/lib/Target/TargetLoweringObjectFile.cpp b/lib/Target/TargetLoweringObjectFile.cpp index 421f1e8fa83..19b5e2a0f97 100644 --- a/lib/Target/TargetLoweringObjectFile.cpp +++ b/lib/Target/TargetLoweringObjectFile.cpp @@ -13,56 +13,46 @@ //===----------------------------------------------------------------------===// #include "llvm/Target/TargetLoweringObjectFile.h" -#include "llvm/Constants.h" -#include "llvm/DerivedTypes.h" -#include "llvm/Function.h" -#include "llvm/GlobalVariable.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/DataLayout.h" +#include "llvm/IR/DerivedTypes.h" +#include "llvm/IR/Function.h" +#include "llvm/IR/GlobalVariable.h" +#include "llvm/IR/Mangler.h" +#include "llvm/MC/MCAsmInfo.h" #include "llvm/MC/MCContext.h" #include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCStreamer.h" #include "llvm/MC/MCSymbol.h" -#include "llvm/Target/Mangler.h" -#include "llvm/Target/TargetData.h" -#include "llvm/Target/TargetMachine.h" -#include "llvm/Target/TargetOptions.h" #include "llvm/Support/Dwarf.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/raw_ostream.h" -#include "llvm/ADT/SmallString.h" +#include "llvm/Target/TargetLowering.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetOptions.h" +#include "llvm/Target/TargetSubtargetInfo.h" using namespace llvm; //===----------------------------------------------------------------------===// // Generic Code //===----------------------------------------------------------------------===// -TargetLoweringObjectFile::TargetLoweringObjectFile() : Ctx(0) { - TextSection = 0; - DataSection = 0; - BSSSection = 0; - ReadOnlySection = 0; - StaticCtorSection = 0; - StaticDtorSection = 0; - LSDASection = 0; - EHFrameSection = 0; - - DwarfAbbrevSection = 0; - DwarfInfoSection = 0; - DwarfLineSection = 0; - DwarfFrameSection = 0; - DwarfPubNamesSection = 0; - DwarfPubTypesSection = 0; - DwarfDebugInlineSection = 0; - DwarfStrSection = 0; - DwarfLocSection = 0; - DwarfARangesSection = 0; - DwarfRangesSection = 0; - DwarfMacroInfoSection = 0; +/// Initialize - this method must be called before any actual lowering is +/// done. This specifies the current context for codegen, and gives the +/// lowering implementations a chance to set up their default sections. +void TargetLoweringObjectFile::Initialize(MCContext &ctx, + const TargetMachine &TM) { + Ctx = &ctx; + DL = TM.getDataLayout(); + InitMCObjectFileInfo(TM.getTargetTriple(), TM.getRelocationModel(), + TM.getCodeModel(), *Ctx); } TargetLoweringObjectFile::~TargetLoweringObjectFile() { } -static bool isSuitableForBSS(const GlobalVariable *GV) { - Constant *C = GV->getInitializer(); +static bool isSuitableForBSS(const GlobalVariable *GV, bool NoZerosInBSS) { + const Constant *C = GV->getInitializer(); // Must have zero initializer. if (!C->isNullValue()) @@ -73,7 +63,7 @@ static bool isSuitableForBSS(const GlobalVariable *GV) { return false; // If the global has an explicit section specified, don't put it in BSS. - if (!GV->getSection().empty()) + if (GV->hasSection()) return false; // If -nozero-initialized-in-bss is specified, don't ever use BSS. @@ -86,35 +76,55 @@ static bool isSuitableForBSS(const GlobalVariable *GV) { /// IsNullTerminatedString - Return true if the specified constant (which is /// known to have a type that is an array of 1/2/4 byte elements) ends with a -/// nul value and contains no other nuls in it. +/// nul value and contains no other nuls in it. Note that this is more general +/// than ConstantDataSequential::isString because we allow 2 & 4 byte strings. static bool IsNullTerminatedString(const Constant *C) { - const ArrayType *ATy = cast(C->getType()); - - // First check: is we have constant array of i8 terminated with zero - if (const ConstantArray *CVA = dyn_cast(C)) { - if (ATy->getNumElements() == 0) return false; - - ConstantInt *Null = - dyn_cast(CVA->getOperand(ATy->getNumElements()-1)); - if (Null == 0 || Null->getZExtValue() != 0) + // First check: is we have constant array terminated with zero + if (const ConstantDataSequential *CDS = dyn_cast(C)) { + unsigned NumElts = CDS->getNumElements(); + assert(NumElts != 0 && "Can't have an empty CDS"); + + if (CDS->getElementAsInteger(NumElts-1) != 0) return false; // Not null terminated. - + // Verify that the null doesn't occur anywhere else in the string. - for (unsigned i = 0, e = ATy->getNumElements()-1; i != e; ++i) - // Reject constantexpr elements etc. - if (!isa(CVA->getOperand(i)) || - CVA->getOperand(i) == Null) + for (unsigned i = 0; i != NumElts-1; ++i) + if (CDS->getElementAsInteger(i) == 0) return false; return true; } // Another possibility: [1 x i8] zeroinitializer if (isa(C)) - return ATy->getNumElements() == 1; + return cast(C->getType())->getNumElements() == 1; return false; } +MCSymbol *TargetLoweringObjectFile::getSymbolWithGlobalValueBase( + const GlobalValue *GV, StringRef Suffix, Mangler &Mang, + const TargetMachine &TM) const { + assert(!Suffix.empty()); + + SmallString<60> NameStr; + NameStr += DL->getPrivateGlobalPrefix(); + TM.getNameWithPrefix(NameStr, GV, Mang); + NameStr.append(Suffix.begin(), Suffix.end()); + return Ctx->getOrCreateSymbol(NameStr); +} + +MCSymbol *TargetLoweringObjectFile::getCFIPersonalitySymbol( + const GlobalValue *GV, Mangler &Mang, const TargetMachine &TM, + MachineModuleInfo *MMI) const { + return TM.getSymbol(GV, Mang); +} + +void TargetLoweringObjectFile::emitPersonalityValue(MCStreamer &Streamer, + const TargetMachine &TM, + const MCSymbol *Sym) const { +} + + /// getKindForGlobal - This is a top-level target-independent classifier for /// a global variable. Given an global variable and information from TM, it /// classifies the global in a variety of ways that make various target @@ -129,12 +139,12 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, // Early exit - functions should be always in text sections. const GlobalVariable *GVar = dyn_cast(GV); - if (GVar == 0) + if (!GVar) return SectionKind::getText(); // Handle thread-local data first. if (GVar->isThreadLocal()) { - if (isSuitableForBSS(GVar)) + if (isSuitableForBSS(GVar, TM.Options.NoZerosInBSS)) return SectionKind::getThreadBSS(); return SectionKind::getThreadData(); } @@ -144,7 +154,7 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, return SectionKind::getCommon(); // Variable can be easily put to BSS section. - if (isSuitableForBSS(GVar)) { + if (isSuitableForBSS(GVar, TM.Options.NoZerosInBSS)) { if (GVar->hasLocalLinkage()) return SectionKind::getBSSLocal(); else if (GVar->hasExternalLinkage()) @@ -152,21 +162,26 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, return SectionKind::getBSS(); } - Constant *C = GVar->getInitializer(); + const Constant *C = GVar->getInitializer(); // If the global is marked constant, we can put it into a mergable section, // a mergable string section, or general .data if it contains relocations. if (GVar->isConstant()) { // If the initializer for the global contains something that requires a - // relocation, then we may have to drop this into a wriable data section + // relocation, then we may have to drop this into a writable data section // even though it is marked const. switch (C->getRelocationInfo()) { - default: assert(0 && "unknown relocation info kind"); case Constant::NoRelocation: + // If the global is required to have a unique address, it can't be put + // into a mergable section: just drop it into the general read-only + // section instead. + if (!GVar->hasUnnamedAddr()) + return SectionKind::getReadOnly(); + // If initializer is a null-terminated string, put it in a "cstring" // section of the right width. - if (const ArrayType *ATy = dyn_cast(C->getType())) { - if (const IntegerType *ITy = + if (ArrayType *ATy = dyn_cast(C->getType())) { + if (IntegerType *ITy = dyn_cast(ATy->getElementType())) { if ((ITy->getBitWidth() == 8 || ITy->getBitWidth() == 16 || ITy->getBitWidth() == 32) && @@ -185,11 +200,12 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, // Otherwise, just drop it into a mergable constant section. If we have // a section for this size, use it, otherwise use the arbitrary sized // mergable section. - switch (TM.getTargetData()->getTypeAllocSize(C->getType())) { + switch (TM.getDataLayout()->getTypeAllocSize(C->getType())) { case 4: return SectionKind::getMergeableConst4(); case 8: return SectionKind::getMergeableConst8(); case 16: return SectionKind::getMergeableConst16(); - default: return SectionKind::getMergeableConst(); + default: + return SectionKind::getReadOnly(); } case Constant::LocalRelocation: @@ -229,7 +245,6 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, return SectionKind::getDataNoRel(); switch (C->getRelocationInfo()) { - default: assert(0 && "unknown relocation info kind"); case Constant::NoRelocation: return SectionKind::getDataNoRel(); case Constant::LocalRelocation: @@ -237,14 +252,16 @@ SectionKind TargetLoweringObjectFile::getKindForGlobal(const GlobalValue *GV, case Constant::GlobalRelocations: return SectionKind::getDataRel(); } + llvm_unreachable("Invalid relocation"); } -/// SectionForGlobal - This method computes the appropriate section to emit -/// the specified global variable or function definition. This should not -/// be passed external (or available externally) globals. -const MCSection *TargetLoweringObjectFile:: -SectionForGlobal(const GlobalValue *GV, SectionKind Kind, Mangler *Mang, - const TargetMachine &TM) const { +/// This method computes the appropriate section to emit the specified global +/// variable or function definition. This should not be passed external (or +/// available externally) globals. +MCSection * +TargetLoweringObjectFile::SectionForGlobal(const GlobalValue *GV, + SectionKind Kind, Mangler &Mang, + const TargetMachine &TM) const { // Select section name. if (GV->hasSection()) return getExplicitSectionGlobal(GV, Kind, Mang, TM); @@ -254,92 +271,81 @@ SectionForGlobal(const GlobalValue *GV, SectionKind Kind, Mangler *Mang, return SelectSectionForGlobal(GV, Kind, Mang, TM); } +MCSection *TargetLoweringObjectFile::getSectionForJumpTable( + const Function &F, Mangler &Mang, const TargetMachine &TM) const { + return getSectionForConstant(SectionKind::getReadOnly(), /*C=*/nullptr); +} -// Lame default implementation. Calculate the section name for global. -const MCSection * -TargetLoweringObjectFile::SelectSectionForGlobal(const GlobalValue *GV, - SectionKind Kind, - Mangler *Mang, - const TargetMachine &TM) const{ - assert(!Kind.isThreadLocal() && "Doesn't support TLS"); - - if (Kind.isText()) - return getTextSection(); - - if (Kind.isBSS() && BSSSection != 0) - return BSSSection; +bool TargetLoweringObjectFile::shouldPutJumpTableInFunctionSection( + bool UsesLabelDifference, const Function &F) const { + // In PIC mode, we need to emit the jump table to the same section as the + // function body itself, otherwise the label differences won't make sense. + // FIXME: Need a better predicate for this: what about custom entries? + if (UsesLabelDifference) + return true; - if (Kind.isReadOnly() && ReadOnlySection != 0) - return ReadOnlySection; + // We should also do if the section name is NULL or function is declared + // in discardable section + // FIXME: this isn't the right predicate, should be based on the MCSection + // for the function. + if (F.isWeakForLinker()) + return true; - return getDataSection(); + return false; } -/// getSectionForConstant - Given a mergable constant with the -/// specified size and relocation information, return a section that it -/// should be placed in. -const MCSection * -TargetLoweringObjectFile::getSectionForConstant(SectionKind Kind) const { - if (Kind.isReadOnly() && ReadOnlySection != 0) +/// Given a mergable constant with the specified size and relocation +/// information, return a section that it should be placed in. +MCSection * +TargetLoweringObjectFile::getSectionForConstant(SectionKind Kind, + const Constant *C) const { + if (Kind.isReadOnly() && ReadOnlySection != nullptr) return ReadOnlySection; return DataSection; } -/// getSymbolForDwarfGlobalReference - Return an MCExpr to use for a +/// getTTypeGlobalReference - Return an MCExpr to use for a /// reference to the specified global variable from exception /// handling information. -const MCExpr *TargetLoweringObjectFile:: -getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang, - MachineModuleInfo *MMI, unsigned Encoding) const { - // FIXME: Use GetGlobalValueSymbol. - SmallString<128> Name; - Mang->getNameWithPrefix(Name, GV, false); - const MCSymbol *Sym; - - if (GV->hasPrivateLinkage()) - Sym = getContext().GetOrCreateTemporarySymbol(Name.str()); - else - Sym = getContext().GetOrCreateSymbol(Name.str()); - - return getSymbolForDwarfReference(Sym, MMI, Encoding); +const MCExpr *TargetLoweringObjectFile::getTTypeGlobalReference( + const GlobalValue *GV, unsigned Encoding, Mangler &Mang, + const TargetMachine &TM, MachineModuleInfo *MMI, + MCStreamer &Streamer) const { + const MCSymbolRefExpr *Ref = + MCSymbolRefExpr::create(TM.getSymbol(GV, Mang), getContext()); + + return getTTypeReference(Ref, Encoding, Streamer); } const MCExpr *TargetLoweringObjectFile:: -getSymbolForDwarfReference(const MCSymbol *Sym, MachineModuleInfo *MMI, - unsigned Encoding) const { - const MCExpr *Res = MCSymbolRefExpr::Create(Sym, getContext()); - - switch (Encoding & 0xF0) { +getTTypeReference(const MCSymbolRefExpr *Sym, unsigned Encoding, + MCStreamer &Streamer) const { + switch (Encoding & 0x70) { default: - llvm_report_error("We do not support this DWARF encoding yet!"); - break; + report_fatal_error("We do not support this DWARF encoding yet!"); case dwarf::DW_EH_PE_absptr: // Do nothing special - break; - case dwarf::DW_EH_PE_pcrel: - // FIXME: PCSymbol - const MCExpr *PC = MCSymbolRefExpr::Create(".", getContext()); - Res = MCBinaryExpr::CreateSub(Res, PC, getContext()); - break; + return Sym; + case dwarf::DW_EH_PE_pcrel: { + // Emit a label to the streamer for the current position. This gives us + // .-foo addressing. + MCSymbol *PCSym = getContext().createTempSymbol(); + Streamer.EmitLabel(PCSym); + const MCExpr *PC = MCSymbolRefExpr::create(PCSym, getContext()); + return MCBinaryExpr::createSub(Sym, PC, getContext()); + } } - - return Res; -} - -unsigned TargetLoweringObjectFile::getPersonalityEncoding() const { - return dwarf::DW_EH_PE_absptr; -} - -unsigned TargetLoweringObjectFile::getLSDAEncoding() const { - return dwarf::DW_EH_PE_absptr; } -unsigned TargetLoweringObjectFile::getFDEEncoding() const { - return dwarf::DW_EH_PE_absptr; +const MCExpr *TargetLoweringObjectFile::getDebugThreadLocalSymbol(const MCSymbol *Sym) const { + // FIXME: It's not clear what, if any, default this should have - perhaps a + // null return could mean 'no location' & we should just do that here. + return MCSymbolRefExpr::create(Sym, *Ctx); } -unsigned TargetLoweringObjectFile::getTTypeEncoding() const { - return dwarf::DW_EH_PE_absptr; +void TargetLoweringObjectFile::getNameWithPrefix( + SmallVectorImpl &OutName, const GlobalValue *GV, + bool CannotUsePrivateLabel, Mangler &Mang, const TargetMachine &TM) const { + Mang.getNameWithPrefix(OutName, GV, CannotUsePrivateLabel); } -