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//===--- BackendUtil.cpp - LLVM Backend Utilities -------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "clang/CodeGen/BackendUtil.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/LangOptions.h"
#include "clang/Basic/TargetOptions.h"
#include "clang/Frontend/CodeGenOptions.h"
#include "clang/Frontend/FrontendDiagnostic.h"
#include "clang/Frontend/Utils.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/Bitcode/BitcodeWriterPass.h"
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/CodeGen/RegAllocRegistry.h"
#include "llvm/CodeGen/SchedulerRegistry.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/ModuleSummaryIndex.h"
#include "llvm/IR/IRPrintingPasses.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Verifier.h"
#include "llvm/MC/SubtargetFeature.h"
#include "llvm/Object/ModuleSummaryIndexObjectFile.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/Timer.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Target/TargetSubtargetInfo.h"
#include "llvm/Transforms/IPO.h"
#include "llvm/Transforms/IPO/PassManagerBuilder.h"
#include "llvm/Transforms/Instrumentation.h"
#include "llvm/Transforms/ObjCARC.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Scalar/GVN.h"
#include "llvm/Transforms/Utils/SymbolRewriter.h"
#include <memory>
using namespace clang;
using namespace llvm;
namespace {
class EmitAssemblyHelper {
DiagnosticsEngine &Diags;
const CodeGenOptions &CodeGenOpts;
const clang::TargetOptions &TargetOpts;
const LangOptions &LangOpts;
Module *TheModule;
Timer CodeGenerationTime;
mutable legacy::PassManager *CodeGenPasses;
mutable legacy::PassManager *PerModulePasses;
mutable legacy::FunctionPassManager *PerFunctionPasses;
private:
TargetIRAnalysis getTargetIRAnalysis() const {
if (TM)
return TM->getTargetIRAnalysis();
return TargetIRAnalysis();
}
legacy::PassManager *getCodeGenPasses() const {
if (!CodeGenPasses) {
CodeGenPasses = new legacy::PassManager();
CodeGenPasses->add(
createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
}
return CodeGenPasses;
}
legacy::PassManager *getPerModulePasses() const {
if (!PerModulePasses) {
PerModulePasses = new legacy::PassManager();
PerModulePasses->add(
createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
}
return PerModulePasses;
}
legacy::FunctionPassManager *getPerFunctionPasses() const {
if (!PerFunctionPasses) {
PerFunctionPasses = new legacy::FunctionPassManager(TheModule);
PerFunctionPasses->add(
createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
}
return PerFunctionPasses;
}
/// Set LLVM command line options passed through -backend-option.
void setCommandLineOpts();
void CreatePasses(ModuleSummaryIndex *ModuleSummary);
/// Generates the TargetMachine.
/// Returns Null if it is unable to create the target machine.
/// Some of our clang tests specify triples which are not built
/// into clang. This is okay because these tests check the generated
/// IR, and they require DataLayout which depends on the triple.
/// In this case, we allow this method to fail and not report an error.
/// When MustCreateTM is used, we print an error if we are unable to load
/// the requested target.
TargetMachine *CreateTargetMachine(bool MustCreateTM);
/// Add passes necessary to emit assembly or LLVM IR.
///
/// \return True on success.
bool AddEmitPasses(BackendAction Action, raw_pwrite_stream &OS);
public:
EmitAssemblyHelper(DiagnosticsEngine &_Diags, const CodeGenOptions &CGOpts,
const clang::TargetOptions &TOpts,
const LangOptions &LOpts, Module *M)
: Diags(_Diags), CodeGenOpts(CGOpts), TargetOpts(TOpts), LangOpts(LOpts),
TheModule(M), CodeGenerationTime("Code Generation Time"),
CodeGenPasses(nullptr), PerModulePasses(nullptr),
PerFunctionPasses(nullptr) {}
~EmitAssemblyHelper() {
delete CodeGenPasses;
delete PerModulePasses;
delete PerFunctionPasses;
if (CodeGenOpts.DisableFree)
BuryPointer(std::move(TM));
}
std::unique_ptr<TargetMachine> TM;
void EmitAssembly(BackendAction Action, raw_pwrite_stream *OS);
};
// We need this wrapper to access LangOpts and CGOpts from extension functions
// that we add to the PassManagerBuilder.
class PassManagerBuilderWrapper : public PassManagerBuilder {
public:
PassManagerBuilderWrapper(const CodeGenOptions &CGOpts,
const LangOptions &LangOpts)
: PassManagerBuilder(), CGOpts(CGOpts), LangOpts(LangOpts) {}
const CodeGenOptions &getCGOpts() const { return CGOpts; }
const LangOptions &getLangOpts() const { return LangOpts; }
private:
const CodeGenOptions &CGOpts;
const LangOptions &LangOpts;
};
}
static void addObjCARCAPElimPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
if (Builder.OptLevel > 0)
PM.add(createObjCARCAPElimPass());
}
static void addObjCARCExpandPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
if (Builder.OptLevel > 0)
PM.add(createObjCARCExpandPass());
}
static void addObjCARCOptPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
if (Builder.OptLevel > 0)
PM.add(createObjCARCOptPass());
}
static void addAddDiscriminatorsPass(const PassManagerBuilder &Builder,
legacy::PassManagerBase &PM) {
PM.add(createAddDiscriminatorsPass());
}
static void addCleanupPassesForSampleProfiler(
const PassManagerBuilder &Builder, legacy::PassManagerBase &PM) {
// instcombine is needed before sample profile annotation because it converts
// certain function calls to be inlinable. simplifycfg and sroa are needed
// before instcombine for necessary preparation. E.g. load store is eliminated
// properly so that instcombine will not introduce unecessary liverange.
PM.add(createCFGSimplificationPass());
PM.add(createSROAPass());
PM.add(createInstructionCombiningPass());
}
static void addBoundsCheckingPass(const PassManagerBuilder &Builder,
legacy::PassManagerBase &PM) {
PM.add(createBoundsCheckingPass());
}
static void addSanitizerCoveragePass(const PassManagerBuilder &Builder,
legacy::PassManagerBase &PM) {
const PassManagerBuilderWrapper &BuilderWrapper =
static_cast<const PassManagerBuilderWrapper&>(Builder);
const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
SanitizerCoverageOptions Opts;
Opts.CoverageType =
static_cast<SanitizerCoverageOptions::Type>(CGOpts.SanitizeCoverageType);
Opts.IndirectCalls = CGOpts.SanitizeCoverageIndirectCalls;
Opts.TraceBB = CGOpts.SanitizeCoverageTraceBB;
Opts.TraceCmp = CGOpts.SanitizeCoverageTraceCmp;
Opts.Use8bitCounters = CGOpts.SanitizeCoverage8bitCounters;
Opts.TracePC = CGOpts.SanitizeCoverageTracePC;
PM.add(createSanitizerCoverageModulePass(Opts));
}
static void addAddressSanitizerPasses(const PassManagerBuilder &Builder,
legacy::PassManagerBase &PM) {
const PassManagerBuilderWrapper &BuilderWrapper =
static_cast<const PassManagerBuilderWrapper&>(Builder);
const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::Address);
bool UseAfterScope = CGOpts.SanitizeAddressUseAfterScope;
PM.add(createAddressSanitizerFunctionPass(/*CompileKernel*/ false, Recover,
UseAfterScope));
PM.add(createAddressSanitizerModulePass(/*CompileKernel*/false, Recover));
}
static void addKernelAddressSanitizerPasses(const PassManagerBuilder &Builder,
legacy::PassManagerBase &PM) {
PM.add(createAddressSanitizerFunctionPass(
/*CompileKernel*/ true,
/*Recover*/ true, /*UseAfterScope*/ false));
PM.add(createAddressSanitizerModulePass(/*CompileKernel*/true,
/*Recover*/true));
}
static void addMemorySanitizerPass(const PassManagerBuilder &Builder,
legacy::PassManagerBase &PM) {
const PassManagerBuilderWrapper &BuilderWrapper =
static_cast<const PassManagerBuilderWrapper&>(Builder);
const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
PM.add(createMemorySanitizerPass(CGOpts.SanitizeMemoryTrackOrigins));
// MemorySanitizer inserts complex instrumentation that mostly follows
// the logic of the original code, but operates on "shadow" values.
// It can benefit from re-running some general purpose optimization passes.
if (Builder.OptLevel > 0) {
PM.add(createEarlyCSEPass());
PM.add(createReassociatePass());
PM.add(createLICMPass());
PM.add(createGVNPass());
PM.add(createInstructionCombiningPass());
PM.add(createDeadStoreEliminationPass());
}
}
static void addThreadSanitizerPass(const PassManagerBuilder &Builder,
legacy::PassManagerBase &PM) {
PM.add(createThreadSanitizerPass());
}
static void addDataFlowSanitizerPass(const PassManagerBuilder &Builder,
legacy::PassManagerBase &PM) {
const PassManagerBuilderWrapper &BuilderWrapper =
static_cast<const PassManagerBuilderWrapper&>(Builder);
const LangOptions &LangOpts = BuilderWrapper.getLangOpts();
PM.add(createDataFlowSanitizerPass(LangOpts.SanitizerBlacklistFiles));
}
static void addEfficiencySanitizerPass(const PassManagerBuilder &Builder,
legacy::PassManagerBase &PM) {
const PassManagerBuilderWrapper &BuilderWrapper =
static_cast<const PassManagerBuilderWrapper&>(Builder);
const LangOptions &LangOpts = BuilderWrapper.getLangOpts();
EfficiencySanitizerOptions Opts;
if (LangOpts.Sanitize.has(SanitizerKind::EfficiencyCacheFrag))
Opts.ToolType = EfficiencySanitizerOptions::ESAN_CacheFrag;
else if (LangOpts.Sanitize.has(SanitizerKind::EfficiencyWorkingSet))
Opts.ToolType = EfficiencySanitizerOptions::ESAN_WorkingSet;
PM.add(createEfficiencySanitizerPass(Opts));
}
static TargetLibraryInfoImpl *createTLII(llvm::Triple &TargetTriple,
const CodeGenOptions &CodeGenOpts) {
TargetLibraryInfoImpl *TLII = new TargetLibraryInfoImpl(TargetTriple);
if (!CodeGenOpts.SimplifyLibCalls)
TLII->disableAllFunctions();
else {
// Disable individual libc/libm calls in TargetLibraryInfo.
LibFunc::Func F;
for (auto &FuncName : CodeGenOpts.getNoBuiltinFuncs())
if (TLII->getLibFunc(FuncName, F))
TLII->setUnavailable(F);
}
switch (CodeGenOpts.getVecLib()) {
case CodeGenOptions::Accelerate:
TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::Accelerate);
break;
default:
break;
}
return TLII;
}
static void addSymbolRewriterPass(const CodeGenOptions &Opts,
legacy::PassManager *MPM) {
llvm::SymbolRewriter::RewriteDescriptorList DL;
llvm::SymbolRewriter::RewriteMapParser MapParser;
for (const auto &MapFile : Opts.RewriteMapFiles)
MapParser.parse(MapFile, &DL);
MPM->add(createRewriteSymbolsPass(DL));
}
void EmitAssemblyHelper::CreatePasses(ModuleSummaryIndex *ModuleSummary) {
if (CodeGenOpts.DisableLLVMPasses)
return;
unsigned OptLevel = CodeGenOpts.OptimizationLevel;
CodeGenOptions::InliningMethod Inlining = CodeGenOpts.getInlining();
// Handle disabling of LLVM optimization, where we want to preserve the
// internal module before any optimization.
if (CodeGenOpts.DisableLLVMOpts) {
OptLevel = 0;
Inlining = CodeGenOpts.NoInlining;
}
PassManagerBuilderWrapper PMBuilder(CodeGenOpts, LangOpts);
// Figure out TargetLibraryInfo.
Triple TargetTriple(TheModule->getTargetTriple());
PMBuilder.LibraryInfo = createTLII(TargetTriple, CodeGenOpts);
switch (Inlining) {
case CodeGenOptions::NoInlining:
break;
case CodeGenOptions::NormalInlining:
case CodeGenOptions::OnlyHintInlining: {
PMBuilder.Inliner =
createFunctionInliningPass(OptLevel, CodeGenOpts.OptimizeSize);
break;
}
case CodeGenOptions::OnlyAlwaysInlining:
// Respect always_inline.
if (OptLevel == 0)
// Do not insert lifetime intrinsics at -O0.
PMBuilder.Inliner = createAlwaysInlinerPass(false);
else
PMBuilder.Inliner = createAlwaysInlinerPass();
break;
}
PMBuilder.OptLevel = OptLevel;
PMBuilder.SizeLevel = CodeGenOpts.OptimizeSize;
PMBuilder.BBVectorize = CodeGenOpts.VectorizeBB;
PMBuilder.SLPVectorize = CodeGenOpts.VectorizeSLP;
PMBuilder.LoopVectorize = CodeGenOpts.VectorizeLoop;
PMBuilder.DisableUnrollLoops = !CodeGenOpts.UnrollLoops;
PMBuilder.MergeFunctions = CodeGenOpts.MergeFunctions;
PMBuilder.PrepareForThinLTO = CodeGenOpts.EmitSummaryIndex;
PMBuilder.PrepareForLTO = CodeGenOpts.PrepareForLTO;
PMBuilder.RerollLoops = CodeGenOpts.RerollLoops;
legacy::PassManager *MPM = getPerModulePasses();
// If we are performing a ThinLTO importing compile, invoke the LTO
// pipeline and pass down the in-memory module summary index.
if (ModuleSummary) {
PMBuilder.ModuleSummary = ModuleSummary;
PMBuilder.populateThinLTOPassManager(*MPM);
return;
}
// Add target-specific passes that need to run as early as possible.
if (TM)
PMBuilder.addExtension(
PassManagerBuilder::EP_EarlyAsPossible,
[&](const PassManagerBuilder &, legacy::PassManagerBase &PM) {
TM->addEarlyAsPossiblePasses(PM);
});
PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
addAddDiscriminatorsPass);
// In ObjC ARC mode, add the main ARC optimization passes.
if (LangOpts.ObjCAutoRefCount) {
PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
addObjCARCExpandPass);
PMBuilder.addExtension(PassManagerBuilder::EP_ModuleOptimizerEarly,
addObjCARCAPElimPass);
PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
addObjCARCOptPass);
}
if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds)) {
PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
addBoundsCheckingPass);
PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
addBoundsCheckingPass);
}
if (CodeGenOpts.SanitizeCoverageType ||
CodeGenOpts.SanitizeCoverageIndirectCalls ||
CodeGenOpts.SanitizeCoverageTraceCmp) {
PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
addSanitizerCoveragePass);
PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
addSanitizerCoveragePass);
}
if (LangOpts.Sanitize.has(SanitizerKind::Address)) {
PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
addAddressSanitizerPasses);
PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
addAddressSanitizerPasses);
}
if (LangOpts.Sanitize.has(SanitizerKind::KernelAddress)) {
PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
addKernelAddressSanitizerPasses);
PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
addKernelAddressSanitizerPasses);
}
if (LangOpts.Sanitize.has(SanitizerKind::Memory)) {
PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
addMemorySanitizerPass);
PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
addMemorySanitizerPass);
}
if (LangOpts.Sanitize.has(SanitizerKind::Thread)) {
PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
addThreadSanitizerPass);
PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
addThreadSanitizerPass);
}
if (LangOpts.Sanitize.has(SanitizerKind::DataFlow)) {
PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
addDataFlowSanitizerPass);
PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
addDataFlowSanitizerPass);
}
if (LangOpts.Sanitize.hasOneOf(SanitizerKind::Efficiency)) {
PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
addEfficiencySanitizerPass);
PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
addEfficiencySanitizerPass);
}
// Set up the per-function pass manager.
legacy::FunctionPassManager *FPM = getPerFunctionPasses();
if (CodeGenOpts.VerifyModule)
FPM->add(createVerifierPass());
// Set up the per-module pass manager.
if (!CodeGenOpts.RewriteMapFiles.empty())
addSymbolRewriterPass(CodeGenOpts, MPM);
if (!CodeGenOpts.DisableGCov &&
(CodeGenOpts.EmitGcovArcs || CodeGenOpts.EmitGcovNotes)) {
// Not using 'GCOVOptions::getDefault' allows us to avoid exiting if
// LLVM's -default-gcov-version flag is set to something invalid.
GCOVOptions Options;
Options.EmitNotes = CodeGenOpts.EmitGcovNotes;
Options.EmitData = CodeGenOpts.EmitGcovArcs;
memcpy(Options.Version, CodeGenOpts.CoverageVersion, 4);
Options.UseCfgChecksum = CodeGenOpts.CoverageExtraChecksum;
Options.NoRedZone = CodeGenOpts.DisableRedZone;
Options.FunctionNamesInData =
!CodeGenOpts.CoverageNoFunctionNamesInData;
Options.ExitBlockBeforeBody = CodeGenOpts.CoverageExitBlockBeforeBody;
MPM->add(createGCOVProfilerPass(Options));
if (CodeGenOpts.getDebugInfo() == codegenoptions::NoDebugInfo)
MPM->add(createStripSymbolsPass(true));
}
if (CodeGenOpts.hasProfileClangInstr()) {
InstrProfOptions Options;
Options.NoRedZone = CodeGenOpts.DisableRedZone;
Options.InstrProfileOutput = CodeGenOpts.InstrProfileOutput;
MPM->add(createInstrProfilingLegacyPass(Options));
}
if (CodeGenOpts.hasProfileIRInstr()) {
if (!CodeGenOpts.InstrProfileOutput.empty())
PMBuilder.PGOInstrGen = CodeGenOpts.InstrProfileOutput;
else
PMBuilder.PGOInstrGen = "default.profraw";
}
if (CodeGenOpts.hasProfileIRUse())
PMBuilder.PGOInstrUse = CodeGenOpts.ProfileInstrumentUsePath;
if (!CodeGenOpts.SampleProfileFile.empty()) {
MPM->add(createPruneEHPass());
MPM->add(createSampleProfileLoaderPass(CodeGenOpts.SampleProfileFile));
PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
addCleanupPassesForSampleProfiler);
}
PMBuilder.populateFunctionPassManager(*FPM);
PMBuilder.populateModulePassManager(*MPM);
}
void EmitAssemblyHelper::setCommandLineOpts() {
SmallVector<const char *, 16> BackendArgs;
BackendArgs.push_back("clang"); // Fake program name.
if (!CodeGenOpts.DebugPass.empty()) {
BackendArgs.push_back("-debug-pass");
BackendArgs.push_back(CodeGenOpts.DebugPass.c_str());
}
if (!CodeGenOpts.LimitFloatPrecision.empty()) {
BackendArgs.push_back("-limit-float-precision");
BackendArgs.push_back(CodeGenOpts.LimitFloatPrecision.c_str());
}
for (const std::string &BackendOption : CodeGenOpts.BackendOptions)
BackendArgs.push_back(BackendOption.c_str());
BackendArgs.push_back(nullptr);
llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1,
BackendArgs.data());
}
TargetMachine *EmitAssemblyHelper::CreateTargetMachine(bool MustCreateTM) {
// Create the TargetMachine for generating code.
std::string Error;
std::string Triple = TheModule->getTargetTriple();
const llvm::Target *TheTarget = TargetRegistry::lookupTarget(Triple, Error);
if (!TheTarget) {
if (MustCreateTM)
Diags.Report(diag::err_fe_unable_to_create_target) << Error;
return nullptr;
}
unsigned CodeModel =
llvm::StringSwitch<unsigned>(CodeGenOpts.CodeModel)
.Case("small", llvm::CodeModel::Small)
.Case("kernel", llvm::CodeModel::Kernel)
.Case("medium", llvm::CodeModel::Medium)
.Case("large", llvm::CodeModel::Large)
.Case("default", llvm::CodeModel::Default)
.Default(~0u);
assert(CodeModel != ~0u && "invalid code model!");
llvm::CodeModel::Model CM = static_cast<llvm::CodeModel::Model>(CodeModel);
std::string FeaturesStr =
llvm::join(TargetOpts.Features.begin(), TargetOpts.Features.end(), ",");
// Keep this synced with the equivalent code in tools/driver/cc1as_main.cpp.
llvm::Optional<llvm::Reloc::Model> RM;
if (CodeGenOpts.RelocationModel == "static") {
RM = llvm::Reloc::Static;
} else if (CodeGenOpts.RelocationModel == "pic") {
RM = llvm::Reloc::PIC_;
} else {
assert(CodeGenOpts.RelocationModel == "dynamic-no-pic" &&
"Invalid PIC model!");
RM = llvm::Reloc::DynamicNoPIC;
}
CodeGenOpt::Level OptLevel = CodeGenOpt::Default;
switch (CodeGenOpts.OptimizationLevel) {
default: break;
case 0: OptLevel = CodeGenOpt::None; break;
case 3: OptLevel = CodeGenOpt::Aggressive; break;
}
llvm::TargetOptions Options;
if (!TargetOpts.Reciprocals.empty())
Options.Reciprocals = TargetRecip(TargetOpts.Reciprocals);
Options.ThreadModel =
llvm::StringSwitch<llvm::ThreadModel::Model>(CodeGenOpts.ThreadModel)
.Case("posix", llvm::ThreadModel::POSIX)
.Case("single", llvm::ThreadModel::Single);
// Set float ABI type.
assert((CodeGenOpts.FloatABI == "soft" || CodeGenOpts.FloatABI == "softfp" ||
CodeGenOpts.FloatABI == "hard" || CodeGenOpts.FloatABI.empty()) &&
"Invalid Floating Point ABI!");
Options.FloatABIType =
llvm::StringSwitch<llvm::FloatABI::ABIType>(CodeGenOpts.FloatABI)
.Case("soft", llvm::FloatABI::Soft)
.Case("softfp", llvm::FloatABI::Soft)
.Case("hard", llvm::FloatABI::Hard)
.Default(llvm::FloatABI::Default);
// Set FP fusion mode.
switch (CodeGenOpts.getFPContractMode()) {
case CodeGenOptions::FPC_Off:
Options.AllowFPOpFusion = llvm::FPOpFusion::Strict;
break;
case CodeGenOptions::FPC_On:
Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
break;
case CodeGenOptions::FPC_Fast:
Options.AllowFPOpFusion = llvm::FPOpFusion::Fast;
break;
}
Options.UseInitArray = CodeGenOpts.UseInitArray;
Options.DisableIntegratedAS = CodeGenOpts.DisableIntegratedAS;
Options.CompressDebugSections = CodeGenOpts.CompressDebugSections;
Options.RelaxELFRelocations = CodeGenOpts.RelaxELFRelocations;
// Set EABI version.
Options.EABIVersion = llvm::StringSwitch<llvm::EABI>(TargetOpts.EABIVersion)
.Case("4", llvm::EABI::EABI4)
.Case("5", llvm::EABI::EABI5)
.Case("gnu", llvm::EABI::GNU)
.Default(llvm::EABI::Default);
if (LangOpts.SjLjExceptions)
Options.ExceptionModel = llvm::ExceptionHandling::SjLj;
Options.LessPreciseFPMADOption = CodeGenOpts.LessPreciseFPMAD;
Options.NoInfsFPMath = CodeGenOpts.NoInfsFPMath;
Options.NoNaNsFPMath = CodeGenOpts.NoNaNsFPMath;
Options.NoZerosInBSS = CodeGenOpts.NoZeroInitializedInBSS;
Options.UnsafeFPMath = CodeGenOpts.UnsafeFPMath;
Options.StackAlignmentOverride = CodeGenOpts.StackAlignment;
Options.FunctionSections = CodeGenOpts.FunctionSections;
Options.DataSections = CodeGenOpts.DataSections;
Options.UniqueSectionNames = CodeGenOpts.UniqueSectionNames;
Options.EmulatedTLS = CodeGenOpts.EmulatedTLS;
Options.DebuggerTuning = CodeGenOpts.getDebuggerTuning();
Options.MCOptions.MCRelaxAll = CodeGenOpts.RelaxAll;
Options.MCOptions.MCSaveTempLabels = CodeGenOpts.SaveTempLabels;
Options.MCOptions.MCUseDwarfDirectory = !CodeGenOpts.NoDwarfDirectoryAsm;
Options.MCOptions.MCNoExecStack = CodeGenOpts.NoExecStack;
Options.MCOptions.MCIncrementalLinkerCompatible =
CodeGenOpts.IncrementalLinkerCompatible;
Options.MCOptions.MCFatalWarnings = CodeGenOpts.FatalWarnings;
Options.MCOptions.AsmVerbose = CodeGenOpts.AsmVerbose;
Options.MCOptions.ABIName = TargetOpts.ABI;
TargetMachine *TM = TheTarget->createTargetMachine(Triple, TargetOpts.CPU,
FeaturesStr, Options,
RM, CM, OptLevel);
return TM;
}
bool EmitAssemblyHelper::AddEmitPasses(BackendAction Action,
raw_pwrite_stream &OS) {
// Create the code generator passes.
legacy::PassManager *PM = getCodeGenPasses();
// Add LibraryInfo.
llvm::Triple TargetTriple(TheModule->getTargetTriple());
std::unique_ptr<TargetLibraryInfoImpl> TLII(
createTLII(TargetTriple, CodeGenOpts));
PM->add(new TargetLibraryInfoWrapperPass(*TLII));
// Normal mode, emit a .s or .o file by running the code generator. Note,
// this also adds codegenerator level optimization passes.
TargetMachine::CodeGenFileType CGFT = TargetMachine::CGFT_AssemblyFile;
if (Action == Backend_EmitObj)
CGFT = TargetMachine::CGFT_ObjectFile;
else if (Action == Backend_EmitMCNull)
CGFT = TargetMachine::CGFT_Null;
else
assert(Action == Backend_EmitAssembly && "Invalid action!");
// Add ObjC ARC final-cleanup optimizations. This is done as part of the
// "codegen" passes so that it isn't run multiple times when there is
// inlining happening.
if (CodeGenOpts.OptimizationLevel > 0)
PM->add(createObjCARCContractPass());
if (TM->addPassesToEmitFile(*PM, OS, CGFT,
/*DisableVerify=*/!CodeGenOpts.VerifyModule)) {
Diags.Report(diag::err_fe_unable_to_interface_with_target);
return false;
}
return true;
}
void EmitAssemblyHelper::EmitAssembly(BackendAction Action,
raw_pwrite_stream *OS) {
TimeRegion Region(llvm::TimePassesIsEnabled ? &CodeGenerationTime : nullptr);
setCommandLineOpts();
bool UsesCodeGen = (Action != Backend_EmitNothing &&
Action != Backend_EmitBC &&
Action != Backend_EmitLL);
if (!TM)
TM.reset(CreateTargetMachine(UsesCodeGen));
if (UsesCodeGen && !TM)
return;
if (TM)
TheModule->setDataLayout(TM->createDataLayout());
// If we are performing a ThinLTO importing compile, load the function
// index into memory and pass it into CreatePasses, which will add it
// to the PassManagerBuilder and invoke LTO passes.
std::unique_ptr<ModuleSummaryIndex> ModuleSummary;
if (!CodeGenOpts.ThinLTOIndexFile.empty()) {
ErrorOr<std::unique_ptr<ModuleSummaryIndex>> IndexOrErr =
llvm::getModuleSummaryIndexForFile(
CodeGenOpts.ThinLTOIndexFile, [&](const DiagnosticInfo &DI) {
TheModule->getContext().diagnose(DI);
});
if (std::error_code EC = IndexOrErr.getError()) {
std::string Error = EC.message();
errs() << "Error loading index file '" << CodeGenOpts.ThinLTOIndexFile
<< "': " << Error << "\n";
return;
}
ModuleSummary = std::move(IndexOrErr.get());
assert(ModuleSummary && "Expected non-empty module summary index");
}
CreatePasses(ModuleSummary.get());
switch (Action) {
case Backend_EmitNothing:
break;
case Backend_EmitBC:
getPerModulePasses()->add(createBitcodeWriterPass(
*OS, CodeGenOpts.EmitLLVMUseLists, CodeGenOpts.EmitSummaryIndex,
CodeGenOpts.EmitSummaryIndex));
break;
case Backend_EmitLL:
getPerModulePasses()->add(
createPrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists));
break;
default:
if (!AddEmitPasses(Action, *OS))
return;
}
// Before executing passes, print the final values of the LLVM options.
cl::PrintOptionValues();
// Run passes. For now we do all passes at once, but eventually we
// would like to have the option of streaming code generation.
if (PerFunctionPasses) {
PrettyStackTraceString CrashInfo("Per-function optimization");
PerFunctionPasses->doInitialization();
for (Function &F : *TheModule)
if (!F.isDeclaration())
PerFunctionPasses->run(F);
PerFunctionPasses->doFinalization();
}
if (PerModulePasses) {
PrettyStackTraceString CrashInfo("Per-module optimization passes");
PerModulePasses->run(*TheModule);
}
if (CodeGenPasses) {
PrettyStackTraceString CrashInfo("Code generation");
CodeGenPasses->run(*TheModule);
}
}
void clang::EmitBackendOutput(DiagnosticsEngine &Diags,
const CodeGenOptions &CGOpts,
const clang::TargetOptions &TOpts,
const LangOptions &LOpts, const llvm::DataLayout &TDesc,
Module *M, BackendAction Action,
raw_pwrite_stream *OS) {
EmitAssemblyHelper AsmHelper(Diags, CGOpts, TOpts, LOpts, M);
AsmHelper.EmitAssembly(Action, OS);
// Verify clang's TargetInfo DataLayout against the LLVM TargetMachine's
// DataLayout.
if (AsmHelper.TM) {
std::string DLDesc = M->getDataLayout().getStringRepresentation();
if (DLDesc != TDesc.getStringRepresentation()) {
unsigned DiagID = Diags.getCustomDiagID(
DiagnosticsEngine::Error, "backend data layout '%0' does not match "
"expected target description '%1'");
Diags.Report(DiagID) << DLDesc << TDesc.getStringRepresentation();
}
}
}
static const char* getSectionNameForBitcode(const Triple &T) {
switch (T.getObjectFormat()) {
case Triple::MachO:
return "__LLVM,__bitcode";
case Triple::COFF:
case Triple::ELF:
case Triple::UnknownObjectFormat:
return ".llvmbc";
}
llvm_unreachable("Unimplemented ObjectFormatType");
}
static const char* getSectionNameForCommandline(const Triple &T) {
switch (T.getObjectFormat()) {
case Triple::MachO:
return "__LLVM,__cmdline";
case Triple::COFF:
case Triple::ELF:
case Triple::UnknownObjectFormat:
return ".llvmcmd";
}
llvm_unreachable("Unimplemented ObjectFormatType");
}
// With -fembed-bitcode, save a copy of the llvm IR as data in the
// __LLVM,__bitcode section.
void clang::EmbedBitcode(llvm::Module *M, const CodeGenOptions &CGOpts,
llvm::MemoryBufferRef Buf) {
if (CGOpts.getEmbedBitcode() == CodeGenOptions::Embed_Off)
return;
// Save llvm.compiler.used and remote it.
SmallVector<Constant*, 2> UsedArray;
SmallSet<GlobalValue*, 4> UsedGlobals;
Type *UsedElementType = Type::getInt8Ty(M->getContext())->getPointerTo(0);
GlobalVariable *Used = collectUsedGlobalVariables(*M, UsedGlobals, true);
for (auto *GV : UsedGlobals) {
if (GV->getName() != "llvm.embedded.module" &&
GV->getName() != "llvm.cmdline")
UsedArray.push_back(
ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
}
if (Used)
Used->eraseFromParent();
// Embed the bitcode for the llvm module.
std::string Data;
ArrayRef<uint8_t> ModuleData;
Triple T(M->getTargetTriple());
// Create a constant that contains the bitcode.
// In case of embedding a marker, ignore the input Buf and use the empty
// ArrayRef. It is also legal to create a bitcode marker even Buf is empty.
if (CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Marker) {
if (!isBitcode((const unsigned char *)Buf.getBufferStart(),
(const unsigned char *)Buf.getBufferEnd())) {
// If the input is LLVM Assembly, bitcode is produced by serializing
// the module. Use-lists order need to be perserved in this case.
llvm::raw_string_ostream OS(Data);
llvm::WriteBitcodeToFile(M, OS, /* ShouldPreserveUseListOrder */ true);
ModuleData =
ArrayRef<uint8_t>((const uint8_t *)OS.str().data(), OS.str().size());
} else
// If the input is LLVM bitcode, write the input byte stream directly.
ModuleData = ArrayRef<uint8_t>((const uint8_t *)Buf.getBufferStart(),
Buf.getBufferSize());
}
llvm::Constant *ModuleConstant =
llvm::ConstantDataArray::get(M->getContext(), ModuleData);
llvm::GlobalVariable *GV = new llvm::GlobalVariable(
*M, ModuleConstant->getType(), true, llvm::GlobalValue::PrivateLinkage,
ModuleConstant);
GV->setSection(getSectionNameForBitcode(T));
UsedArray.push_back(
ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
if (llvm::GlobalVariable *Old =
M->getGlobalVariable("llvm.embedded.module", true)) {
assert(Old->hasOneUse() &&
"llvm.embedded.module can only be used once in llvm.compiler.used");
GV->takeName(Old);
Old->eraseFromParent();
} else {
GV->setName("llvm.embedded.module");
}
// Skip if only bitcode needs to be embedded.
if (CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Bitcode) {
// Embed command-line options.
ArrayRef<uint8_t> CmdData(const_cast<uint8_t *>(CGOpts.CmdArgs.data()),
CGOpts.CmdArgs.size());
llvm::Constant *CmdConstant =
llvm::ConstantDataArray::get(M->getContext(), CmdData);
GV = new llvm::GlobalVariable(*M, CmdConstant->getType(), true,
llvm::GlobalValue::PrivateLinkage,
CmdConstant);
GV->setSection(getSectionNameForCommandline(T));
UsedArray.push_back(
ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
if (llvm::GlobalVariable *Old =
M->getGlobalVariable("llvm.cmdline", true)) {
assert(Old->hasOneUse() &&
"llvm.cmdline can only be used once in llvm.compiler.used");
GV->takeName(Old);
Old->eraseFromParent();
} else {
GV->setName("llvm.cmdline");
}
}
if (UsedArray.empty())
return;
// Recreate llvm.compiler.used.
ArrayType *ATy = ArrayType::get(UsedElementType, UsedArray.size());
auto *NewUsed = new GlobalVariable(
*M, ATy, false, llvm::GlobalValue::AppendingLinkage,
llvm::ConstantArray::get(ATy, UsedArray), "llvm.compiler.used");
NewUsed->setSection("llvm.metadata");
}