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Diffstat (limited to 'clang/lib/CodeGen/BackendUtil.cpp')
| -rw-r--r-- | clang/lib/CodeGen/BackendUtil.cpp | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp new file mode 100644 index 0000000..2f44711 --- /dev/null +++ b/clang/lib/CodeGen/BackendUtil.cpp @@ -0,0 +1,460 @@ +//===--- 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/TargetOptions.h" +#include "clang/Basic/LangOptions.h" +#include "clang/Frontend/CodeGenOptions.h" +#include "clang/Frontend/FrontendDiagnostic.h" +#include "llvm/Module.h" +#include "llvm/PassManager.h" +#include "llvm/Analysis/Verifier.h" +#include "llvm/Assembly/PrintModulePass.h" +#include "llvm/Bitcode/ReaderWriter.h" +#include "llvm/CodeGen/RegAllocRegistry.h" +#include "llvm/CodeGen/SchedulerRegistry.h" +#include "llvm/MC/SubtargetFeature.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/FormattedStream.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/TargetData.h" +#include "llvm/Target/TargetLibraryInfo.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetOptions.h" +#include "llvm/Transforms/Instrumentation.h" +#include "llvm/Transforms/IPO.h" +#include "llvm/Transforms/IPO/PassManagerBuilder.h" +#include "llvm/Transforms/Scalar.h" +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 PassManager *CodeGenPasses; + mutable PassManager *PerModulePasses; + mutable FunctionPassManager *PerFunctionPasses; + +private: + PassManager *getCodeGenPasses() const { + if (!CodeGenPasses) { + CodeGenPasses = new PassManager(); + CodeGenPasses->add(new TargetData(TheModule)); + } + return CodeGenPasses; + } + + PassManager *getPerModulePasses() const { + if (!PerModulePasses) { + PerModulePasses = new PassManager(); + PerModulePasses->add(new TargetData(TheModule)); + } + return PerModulePasses; + } + + FunctionPassManager *getPerFunctionPasses() const { + if (!PerFunctionPasses) { + PerFunctionPasses = new FunctionPassManager(TheModule); + PerFunctionPasses->add(new TargetData(TheModule)); + } + return PerFunctionPasses; + } + + void CreatePasses(); + + /// AddEmitPasses - Add passes necessary to emit assembly or LLVM IR. + /// + /// \return True on success. + bool AddEmitPasses(BackendAction Action, formatted_raw_ostream &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(0), PerModulePasses(0), PerFunctionPasses(0) {} + + ~EmitAssemblyHelper() { + delete CodeGenPasses; + delete PerModulePasses; + delete PerFunctionPasses; + } + + void EmitAssembly(BackendAction Action, raw_ostream *OS); +}; + +} + +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 addAddressSanitizerPass(const PassManagerBuilder &Builder, + PassManagerBase &PM) { + PM.add(createAddressSanitizerPass()); +} + +static void addThreadSanitizerPass(const PassManagerBuilder &Builder, + PassManagerBase &PM) { + PM.add(createThreadSanitizerPass()); +} + +void EmitAssemblyHelper::CreatePasses() { + unsigned OptLevel = CodeGenOpts.OptimizationLevel; + CodeGenOptions::InliningMethod Inlining = CodeGenOpts.Inlining; + + // Handle disabling of LLVM optimization, where we want to preserve the + // internal module before any optimization. + if (CodeGenOpts.DisableLLVMOpts) { + OptLevel = 0; + Inlining = CodeGenOpts.NoInlining; + } + + PassManagerBuilder PMBuilder; + PMBuilder.OptLevel = OptLevel; + PMBuilder.SizeLevel = CodeGenOpts.OptimizeSize; + + PMBuilder.DisableSimplifyLibCalls = !CodeGenOpts.SimplifyLibCalls; + PMBuilder.DisableUnitAtATime = !CodeGenOpts.UnitAtATime; + PMBuilder.DisableUnrollLoops = !CodeGenOpts.UnrollLoops; + + // 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.AddressSanitizer) { + PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate, + addAddressSanitizerPass); + PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0, + addAddressSanitizerPass); + } + + if (LangOpts.ThreadSanitizer) { + PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast, + addThreadSanitizerPass); + PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0, + addThreadSanitizerPass); + } + + // Figure out TargetLibraryInfo. + Triple TargetTriple(TheModule->getTargetTriple()); + PMBuilder.LibraryInfo = new TargetLibraryInfo(TargetTriple); + if (!CodeGenOpts.SimplifyLibCalls) + PMBuilder.LibraryInfo->disableAllFunctions(); + + switch (Inlining) { + case CodeGenOptions::NoInlining: break; + case CodeGenOptions::NormalInlining: { + // FIXME: Derive these constants in a principled fashion. + unsigned Threshold = 225; + if (CodeGenOpts.OptimizeSize == 1) // -Os + Threshold = 75; + else if (CodeGenOpts.OptimizeSize == 2) // -Oz + Threshold = 25; + else if (OptLevel > 2) + Threshold = 275; + PMBuilder.Inliner = createFunctionInliningPass(Threshold); + 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; + } + + + // Set up the per-function pass manager. + FunctionPassManager *FPM = getPerFunctionPasses(); + if (CodeGenOpts.VerifyModule) + FPM->add(createVerifierPass()); + PMBuilder.populateFunctionPassManager(*FPM); + + // Set up the per-module pass manager. + PassManager *MPM = getPerModulePasses(); + + if (CodeGenOpts.EmitGcovArcs || CodeGenOpts.EmitGcovNotes) { + MPM->add(createGCOVProfilerPass(CodeGenOpts.EmitGcovNotes, + CodeGenOpts.EmitGcovArcs, + TargetTriple.isMacOSX())); + + if (!CodeGenOpts.DebugInfo) + MPM->add(createStripSymbolsPass(true)); + } + + + PMBuilder.populateModulePassManager(*MPM); +} + +bool EmitAssemblyHelper::AddEmitPasses(BackendAction Action, + formatted_raw_ostream &OS) { + // Create the TargetMachine for generating code. + std::string Error; + std::string Triple = TheModule->getTargetTriple(); + const llvm::Target *TheTarget = TargetRegistry::lookupTarget(Triple, Error); + if (!TheTarget) { + Diags.Report(diag::err_fe_unable_to_create_target) << Error; + return false; + } + + // FIXME: Expose these capabilities via actual APIs!!!! Aside from just + // being gross, this is also totally broken if we ever care about + // concurrency. + + TargetMachine::setAsmVerbosityDefault(CodeGenOpts.AsmVerbose); + + TargetMachine::setFunctionSections(CodeGenOpts.FunctionSections); + TargetMachine::setDataSections (CodeGenOpts.DataSections); + + // FIXME: Parse this earlier. + llvm::CodeModel::Model CM; + if (CodeGenOpts.CodeModel == "small") { + CM = llvm::CodeModel::Small; + } else if (CodeGenOpts.CodeModel == "kernel") { + CM = llvm::CodeModel::Kernel; + } else if (CodeGenOpts.CodeModel == "medium") { + CM = llvm::CodeModel::Medium; + } else if (CodeGenOpts.CodeModel == "large") { + CM = llvm::CodeModel::Large; + } else { + assert(CodeGenOpts.CodeModel.empty() && "Invalid code model!"); + CM = llvm::CodeModel::Default; + } + + 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()); + } + if (llvm::TimePassesIsEnabled) + BackendArgs.push_back("-time-passes"); + for (unsigned i = 0, e = CodeGenOpts.BackendOptions.size(); i != e; ++i) + BackendArgs.push_back(CodeGenOpts.BackendOptions[i].c_str()); + if (CodeGenOpts.NoGlobalMerge) + BackendArgs.push_back("-global-merge=false"); + BackendArgs.push_back(0); + llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1, + BackendArgs.data()); + + std::string FeaturesStr; + if (TargetOpts.Features.size()) { + SubtargetFeatures Features; + for (std::vector<std::string>::const_iterator + it = TargetOpts.Features.begin(), + ie = TargetOpts.Features.end(); it != ie; ++it) + Features.AddFeature(*it); + FeaturesStr = Features.getString(); + } + + llvm::Reloc::Model RM = llvm::Reloc::Default; + 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; + + // Set frame pointer elimination mode. + if (!CodeGenOpts.DisableFPElim) { + Options.NoFramePointerElim = false; + Options.NoFramePointerElimNonLeaf = false; + } else if (CodeGenOpts.OmitLeafFramePointer) { + Options.NoFramePointerElim = false; + Options.NoFramePointerElimNonLeaf = true; + } else { + Options.NoFramePointerElim = true; + Options.NoFramePointerElimNonLeaf = true; + } + + // Set float ABI type. + if (CodeGenOpts.FloatABI == "soft" || CodeGenOpts.FloatABI == "softfp") + Options.FloatABIType = llvm::FloatABI::Soft; + else if (CodeGenOpts.FloatABI == "hard") + Options.FloatABIType = llvm::FloatABI::Hard; + else { + assert(CodeGenOpts.FloatABI.empty() && "Invalid float abi!"); + Options.FloatABIType = llvm::FloatABI::Default; + } + + Options.LessPreciseFPMADOption = CodeGenOpts.LessPreciseFPMAD; + Options.NoInfsFPMath = CodeGenOpts.NoInfsFPMath; + Options.NoNaNsFPMath = CodeGenOpts.NoNaNsFPMath; + Options.NoZerosInBSS = CodeGenOpts.NoZeroInitializedInBSS; + Options.UnsafeFPMath = CodeGenOpts.UnsafeFPMath; + Options.UseSoftFloat = CodeGenOpts.SoftFloat; + Options.StackAlignmentOverride = CodeGenOpts.StackAlignment; + Options.RealignStack = CodeGenOpts.StackRealignment; + Options.DisableTailCalls = CodeGenOpts.DisableTailCalls; + Options.TrapFuncName = CodeGenOpts.TrapFuncName; + Options.PositionIndependentExecutable = LangOpts.PIELevel != 0; + + TargetMachine *TM = TheTarget->createTargetMachine(Triple, TargetOpts.CPU, + FeaturesStr, Options, + RM, CM, OptLevel); + + if (CodeGenOpts.RelaxAll) + TM->setMCRelaxAll(true); + if (CodeGenOpts.SaveTempLabels) + TM->setMCSaveTempLabels(true); + if (CodeGenOpts.NoDwarf2CFIAsm) + TM->setMCUseCFI(false); + if (!CodeGenOpts.NoDwarfDirectoryAsm) + TM->setMCUseDwarfDirectory(true); + if (CodeGenOpts.NoExecStack) + TM->setMCNoExecStack(true); + + // Create the code generator passes. + PassManager *PM = getCodeGenPasses(); + + // Add LibraryInfo. + TargetLibraryInfo *TLI = new TargetLibraryInfo(); + if (!CodeGenOpts.SimplifyLibCalls) + TLI->disableAllFunctions(); + PM->add(TLI); + + // 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 (LangOpts.ObjCAutoRefCount && + 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_ostream *OS) { + TimeRegion Region(llvm::TimePassesIsEnabled ? &CodeGenerationTime : 0); + llvm::formatted_raw_ostream FormattedOS; + + CreatePasses(); + switch (Action) { + case Backend_EmitNothing: + break; + + case Backend_EmitBC: + getPerModulePasses()->add(createBitcodeWriterPass(*OS)); + break; + + case Backend_EmitLL: + FormattedOS.setStream(*OS, formatted_raw_ostream::PRESERVE_STREAM); + getPerModulePasses()->add(createPrintModulePass(&FormattedOS)); + break; + + default: + FormattedOS.setStream(*OS, formatted_raw_ostream::PRESERVE_STREAM); + if (!AddEmitPasses(Action, FormattedOS)) + 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 (Module::iterator I = TheModule->begin(), + E = TheModule->end(); I != E; ++I) + if (!I->isDeclaration()) + PerFunctionPasses->run(*I); + 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, + Module *M, + BackendAction Action, raw_ostream *OS) { + EmitAssemblyHelper AsmHelper(Diags, CGOpts, TOpts, LOpts, M); + + AsmHelper.EmitAssembly(Action, OS); +} |