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diff --git a/llvm/lib/Target/TargetMachine.cpp b/llvm/lib/Target/TargetMachine.cpp
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+//===-- TargetMachine.cpp - General Target Information ---------------------==//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file describes the general parts of a Target machine.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/GlobalAlias.h"
+#include "llvm/IR/GlobalValue.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/LegacyPassManager.h"
+#include "llvm/IR/Mangler.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCInstrInfo.h"
+#include "llvm/MC/MCSectionMachO.h"
+#include "llvm/MC/MCTargetOptions.h"
+#include "llvm/MC/SectionKind.h"
+#include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
+using namespace llvm;
+
+//---------------------------------------------------------------------------
+// TargetMachine Class
+//
+
+TargetMachine::TargetMachine(const Target &T, StringRef DataLayoutString,
+ const Triple &TT, StringRef CPU, StringRef FS,
+ const TargetOptions &Options)
+ : TheTarget(T), DL(DataLayoutString), TargetTriple(TT), TargetCPU(CPU),
+ TargetFS(FS), AsmInfo(nullptr), MRI(nullptr), MII(nullptr), STI(nullptr),
+ RequireStructuredCFG(false), DefaultOptions(Options), Options(Options) {
+}
+
+TargetMachine::~TargetMachine() {
+ delete AsmInfo;
+ delete MRI;
+ delete MII;
+ delete STI;
+}
+
+bool TargetMachine::isPositionIndependent() const {
+ return getRelocationModel() == Reloc::PIC_;
+}
+
+/// \brief Reset the target options based on the function's attributes.
+// FIXME: This function needs to go away for a number of reasons:
+// a) global state on the TargetMachine is terrible in general,
+// b) these target options should be passed only on the function
+// and not on the TargetMachine (via TargetOptions) at all.
+void TargetMachine::resetTargetOptions(const Function &F) const {
+#define RESET_OPTION(X, Y) \
+ do { \
+ if (F.hasFnAttribute(Y)) \
+ Options.X = (F.getFnAttribute(Y).getValueAsString() == "true"); \
+ else \
+ Options.X = DefaultOptions.X; \
+ } while (0)
+
+ RESET_OPTION(UnsafeFPMath, "unsafe-fp-math");
+ RESET_OPTION(NoInfsFPMath, "no-infs-fp-math");
+ RESET_OPTION(NoNaNsFPMath, "no-nans-fp-math");
+ RESET_OPTION(NoSignedZerosFPMath, "no-signed-zeros-fp-math");
+ RESET_OPTION(NoTrappingFPMath, "no-trapping-math");
+
+ StringRef Denormal =
+ F.getFnAttribute("denormal-fp-math").getValueAsString();
+ if (Denormal == "ieee")
+ Options.FPDenormalMode = FPDenormal::IEEE;
+ else if (Denormal == "preserve-sign")
+ Options.FPDenormalMode = FPDenormal::PreserveSign;
+ else if (Denormal == "positive-zero")
+ Options.FPDenormalMode = FPDenormal::PositiveZero;
+ else
+ Options.FPDenormalMode = DefaultOptions.FPDenormalMode;
+}
+
+/// Returns the code generation relocation model. The choices are static, PIC,
+/// and dynamic-no-pic.
+Reloc::Model TargetMachine::getRelocationModel() const { return RM; }
+
+/// Returns the code model. The choices are small, kernel, medium, large, and
+/// target default.
+CodeModel::Model TargetMachine::getCodeModel() const { return CMModel; }
+
+/// Get the IR-specified TLS model for Var.
+static TLSModel::Model getSelectedTLSModel(const GlobalValue *GV) {
+ switch (GV->getThreadLocalMode()) {
+ case GlobalVariable::NotThreadLocal:
+ llvm_unreachable("getSelectedTLSModel for non-TLS variable");
+ break;
+ case GlobalVariable::GeneralDynamicTLSModel:
+ return TLSModel::GeneralDynamic;
+ case GlobalVariable::LocalDynamicTLSModel:
+ return TLSModel::LocalDynamic;
+ case GlobalVariable::InitialExecTLSModel:
+ return TLSModel::InitialExec;
+ case GlobalVariable::LocalExecTLSModel:
+ return TLSModel::LocalExec;
+ }
+ llvm_unreachable("invalid TLS model");
+}
+
+bool TargetMachine::shouldAssumeDSOLocal(const Module &M,
+ const GlobalValue *GV) const {
+ Reloc::Model RM = getRelocationModel();
+ const Triple &TT = getTargetTriple();
+
+ // DLLImport explicitly marks the GV as external.
+ if (GV && GV->hasDLLImportStorageClass())
+ return false;
+
+ // Every other GV is local on COFF.
+ // Make an exception for windows OS in the triple: Some firmwares builds use
+ // *-win32-macho triples. This (accidentally?) produced windows relocations
+ // without GOT tables in older clang versions; Keep this behaviour.
+ if (TT.isOSBinFormatCOFF() || (TT.isOSWindows() && TT.isOSBinFormatMachO()))
+ return true;
+
+ if (GV && (GV->hasLocalLinkage() || !GV->hasDefaultVisibility()))
+ return true;
+
+ if (TT.isOSBinFormatMachO()) {
+ if (RM == Reloc::Static)
+ return true;
+ return GV && GV->isStrongDefinitionForLinker();
+ }
+
+ assert(TT.isOSBinFormatELF());
+ assert(RM != Reloc::DynamicNoPIC);
+
+ bool IsExecutable =
+ RM == Reloc::Static || M.getPIELevel() != PIELevel::Default;
+ if (IsExecutable) {
+ // If the symbol is defined, it cannot be preempted.
+ if (GV && !GV->isDeclarationForLinker())
+ return true;
+
+ bool IsTLS = GV && GV->isThreadLocal();
+ bool IsAccessViaCopyRelocs = Options.MCOptions.MCPIECopyRelocations && GV &&
+ isa<GlobalVariable>(GV) &&
+ !GV->hasExternalWeakLinkage();
+ Triple::ArchType Arch = TT.getArch();
+ bool IsPPC =
+ Arch == Triple::ppc || Arch == Triple::ppc64 || Arch == Triple::ppc64le;
+ // Check if we can use copy relocations. PowerPC has no copy relocations.
+ if (!IsTLS && !IsPPC && (RM == Reloc::Static || IsAccessViaCopyRelocs))
+ return true;
+ }
+
+ // ELF supports preemption of other symbols.
+ return false;
+}
+
+TLSModel::Model TargetMachine::getTLSModel(const GlobalValue *GV) const {
+ bool IsPIE = GV->getParent()->getPIELevel() != PIELevel::Default;
+ Reloc::Model RM = getRelocationModel();
+ bool IsSharedLibrary = RM == Reloc::PIC_ && !IsPIE;
+ bool IsLocal = shouldAssumeDSOLocal(*GV->getParent(), GV);
+
+ TLSModel::Model Model;
+ if (IsSharedLibrary) {
+ if (IsLocal)
+ Model = TLSModel::LocalDynamic;
+ else
+ Model = TLSModel::GeneralDynamic;
+ } else {
+ if (IsLocal)
+ Model = TLSModel::LocalExec;
+ else
+ Model = TLSModel::InitialExec;
+ }
+
+ // If the user specified a more specific model, use that.
+ TLSModel::Model SelectedModel = getSelectedTLSModel(GV);
+ if (SelectedModel > Model)
+ return SelectedModel;
+
+ return Model;
+}
+
+/// Returns the optimization level: None, Less, Default, or Aggressive.
+CodeGenOpt::Level TargetMachine::getOptLevel() const { return OptLevel; }
+
+void TargetMachine::setOptLevel(CodeGenOpt::Level Level) { OptLevel = Level; }
+
+TargetIRAnalysis TargetMachine::getTargetIRAnalysis() {
+ return TargetIRAnalysis([](const Function &F) {
+ return TargetTransformInfo(F.getParent()->getDataLayout());
+ });
+}
+
+void TargetMachine::getNameWithPrefix(SmallVectorImpl<char> &Name,
+ const GlobalValue *GV, Mangler &Mang,
+ bool MayAlwaysUsePrivate) const {
+ if (MayAlwaysUsePrivate || !GV->hasPrivateLinkage()) {
+ // Simple case: If GV is not private, it is not important to find out if
+ // private labels are legal in this case or not.
+ Mang.getNameWithPrefix(Name, GV, false);
+ return;
+ }
+ const TargetLoweringObjectFile *TLOF = getObjFileLowering();
+ TLOF->getNameWithPrefix(Name, GV, *this);
+}
+
+MCSymbol *TargetMachine::getSymbol(const GlobalValue *GV) const {
+ const TargetLoweringObjectFile *TLOF = getObjFileLowering();
+ SmallString<128> NameStr;
+ getNameWithPrefix(NameStr, GV, TLOF->getMangler());
+ return TLOF->getContext().getOrCreateSymbol(NameStr);
+}
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