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Diffstat (limited to 'contrib/llvm/tools/clang/lib/CodeGen/BackendUtil.cpp')
| -rw-r--r-- | contrib/llvm/tools/clang/lib/CodeGen/BackendUtil.cpp | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/contrib/llvm/tools/clang/lib/CodeGen/BackendUtil.cpp b/contrib/llvm/tools/clang/lib/CodeGen/BackendUtil.cpp new file mode 100644 index 0000000..69efe43 --- /dev/null +++ b/contrib/llvm/tools/clang/lib/CodeGen/BackendUtil.cpp @@ -0,0 +1,339 @@ +//===--- 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/Frontend/CodeGenOptions.h" +#include "clang/Frontend/FrontendDiagnostic.h" +#include "llvm/Module.h" +#include "llvm/PassManager.h" +#include "llvm/Assembly/PrintModulePass.h" +#include "llvm/Bitcode/ReaderWriter.h" +#include "llvm/CodeGen/RegAllocRegistry.h" +#include "llvm/CodeGen/SchedulerRegistry.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/FormattedStream.h" +#include "llvm/Support/PrettyStackTrace.h" +#include "llvm/Support/StandardPasses.h" +#include "llvm/Support/Timer.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/Target/SubtargetFeature.h" +#include "llvm/Target/TargetData.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetOptions.h" +#include "llvm/Target/TargetRegistry.h" +using namespace clang; +using namespace llvm; + +namespace { + +class EmitAssemblyHelper { + Diagnostic &Diags; + const CodeGenOptions &CodeGenOpts; + const TargetOptions &TargetOpts; + Module *TheModule; + + Timer CodeGenerationTime; + + mutable FunctionPassManager *CodeGenPasses; + mutable PassManager *PerModulePasses; + mutable FunctionPassManager *PerFunctionPasses; + +private: + FunctionPassManager *getCodeGenPasses() const { + if (!CodeGenPasses) { + CodeGenPasses = new FunctionPassManager(TheModule); + 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(Diagnostic &_Diags, + const CodeGenOptions &CGOpts, const TargetOptions &TOpts, + Module *M) + : Diags(_Diags), CodeGenOpts(CGOpts), TargetOpts(TOpts), + 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); +}; + +} + +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; + } + + // In -O0 if checking is disabled, we don't even have per-function passes. + if (CodeGenOpts.VerifyModule) + getPerFunctionPasses()->add(createVerifierPass()); + + // Assume that standard function passes aren't run for -O0. + if (OptLevel > 0) + llvm::createStandardFunctionPasses(getPerFunctionPasses(), OptLevel); + + llvm::Pass *InliningPass = 0; + switch (Inlining) { + case CodeGenOptions::NoInlining: break; + case CodeGenOptions::NormalInlining: { + // Set the inline threshold following llvm-gcc. + // + // FIXME: Derive these constants in a principled fashion. + unsigned Threshold = 225; + if (CodeGenOpts.OptimizeSize) + Threshold = 75; + else if (OptLevel > 2) + Threshold = 275; + InliningPass = createFunctionInliningPass(Threshold); + break; + } + case CodeGenOptions::OnlyAlwaysInlining: + InliningPass = createAlwaysInlinerPass(); // Respect always_inline + break; + } + + // For now we always create per module passes. + llvm::createStandardModulePasses(getPerModulePasses(), OptLevel, + CodeGenOpts.OptimizeSize, + CodeGenOpts.UnitAtATime, + CodeGenOpts.UnrollLoops, + CodeGenOpts.SimplifyLibCalls, + /*HaveExceptions=*/true, + InliningPass); +} + +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. + + // Set frame pointer elimination mode. + if (!CodeGenOpts.DisableFPElim) { + llvm::NoFramePointerElim = false; + llvm::NoFramePointerElimNonLeaf = false; + } else if (CodeGenOpts.OmitLeafFramePointer) { + llvm::NoFramePointerElim = false; + llvm::NoFramePointerElimNonLeaf = true; + } else { + llvm::NoFramePointerElim = true; + llvm::NoFramePointerElimNonLeaf = true; + } + + // Set float ABI type. + if (CodeGenOpts.FloatABI == "soft") + llvm::FloatABIType = llvm::FloatABI::Soft; + else if (CodeGenOpts.FloatABI == "hard") + llvm::FloatABIType = llvm::FloatABI::Hard; + else { + assert(CodeGenOpts.FloatABI.empty() && "Invalid float abi!"); + llvm::FloatABIType = llvm::FloatABI::Default; + } + + NoZerosInBSS = CodeGenOpts.NoZeroInitializedInBSS; + llvm::UseSoftFloat = CodeGenOpts.SoftFloat; + UnwindTablesMandatory = CodeGenOpts.UnwindTables; + + TargetMachine::setAsmVerbosityDefault(CodeGenOpts.AsmVerbose); + + TargetMachine::setFunctionSections(CodeGenOpts.FunctionSections); + TargetMachine::setDataSections (CodeGenOpts.DataSections); + + // FIXME: Parse this earlier. + if (CodeGenOpts.RelocationModel == "static") { + TargetMachine::setRelocationModel(llvm::Reloc::Static); + } else if (CodeGenOpts.RelocationModel == "pic") { + TargetMachine::setRelocationModel(llvm::Reloc::PIC_); + } else { + assert(CodeGenOpts.RelocationModel == "dynamic-no-pic" && + "Invalid PIC model!"); + TargetMachine::setRelocationModel(llvm::Reloc::DynamicNoPIC); + } + // FIXME: Parse this earlier. + if (CodeGenOpts.CodeModel == "small") { + TargetMachine::setCodeModel(llvm::CodeModel::Small); + } else if (CodeGenOpts.CodeModel == "kernel") { + TargetMachine::setCodeModel(llvm::CodeModel::Kernel); + } else if (CodeGenOpts.CodeModel == "medium") { + TargetMachine::setCodeModel(llvm::CodeModel::Medium); + } else if (CodeGenOpts.CodeModel == "large") { + TargetMachine::setCodeModel(llvm::CodeModel::Large); + } else { + assert(CodeGenOpts.CodeModel.empty() && "Invalid code model!"); + TargetMachine::setCodeModel(llvm::CodeModel::Default); + } + + std::vector<const char *> 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"); + BackendArgs.push_back(0); + llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1, + const_cast<char **>(&BackendArgs[0])); + + std::string FeaturesStr; + if (TargetOpts.CPU.size() || TargetOpts.Features.size()) { + SubtargetFeatures Features; + Features.setCPU(TargetOpts.CPU); + for (std::vector<std::string>::const_iterator + it = TargetOpts.Features.begin(), + ie = TargetOpts.Features.end(); it != ie; ++it) + Features.AddFeature(*it); + FeaturesStr = Features.getString(); + } + TargetMachine *TM = TheTarget->createTargetMachine(Triple, FeaturesStr); + + if (CodeGenOpts.RelaxAll) + TM->setMCRelaxAll(true); + + // Create the code generator passes. + FunctionPassManager *PM = getCodeGenPasses(); + CodeGenOpt::Level OptLevel = CodeGenOpt::Default; + + switch (CodeGenOpts.OptimizationLevel) { + default: break; + case 0: OptLevel = CodeGenOpt::None; break; + case 3: OptLevel = CodeGenOpt::Aggressive; break; + } + + // 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!"); + if (TM->addPassesToEmitFile(*PM, OS, CGFT, OptLevel, + /*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; + } + + // 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->doInitialization(); + for (Module::iterator I = TheModule->begin(), + E = TheModule->end(); I != E; ++I) + if (!I->isDeclaration()) + CodeGenPasses->run(*I); + CodeGenPasses->doFinalization(); + } +} + +void clang::EmitBackendOutput(Diagnostic &Diags, const CodeGenOptions &CGOpts, + const TargetOptions &TOpts, Module *M, + BackendAction Action, raw_ostream *OS) { + EmitAssemblyHelper AsmHelper(Diags, CGOpts, TOpts, M); + + AsmHelper.EmitAssembly(Action, OS); +} |
