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diff --git a/lib/Frontend/Backend.cpp b/lib/Frontend/Backend.cpp
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+//===--- Backend.cpp - Interface to LLVM backend technologies -------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Frontend/ASTConsumers.h"
+#include "clang/CodeGen/ModuleBuilder.h"
+#include "clang/Frontend/CompileOptions.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/ASTConsumer.h"
+#include "clang/AST/DeclGroup.h"
+#include "clang/Basic/TargetInfo.h"
+#include "llvm/Module.h"
+#include "llvm/ModuleProvider.h"
+#include "llvm/PassManager.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/Assembly/PrintModulePass.h"
+#include "llvm/Analysis/CallGraph.h"
+#include "llvm/Analysis/Verifier.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/CodeGen/RegAllocRegistry.h"
+#include "llvm/CodeGen/SchedulerRegistry.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/Timer.h"
+#include "llvm/System/Path.h"
+#include "llvm/System/Program.h"
+#include "llvm/Target/SubtargetFeature.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetMachineRegistry.h"
+#include "llvm/Transforms/Scalar.h"
+#include "llvm/Transforms/IPO.h"
+using namespace clang;
+using namespace llvm;
+
+namespace {
+ class VISIBILITY_HIDDEN BackendConsumer : public ASTConsumer {
+ BackendAction Action;
+ CompileOptions CompileOpts;
+ llvm::raw_ostream *AsmOutStream;
+ ASTContext *Context;
+
+ Timer LLVMIRGeneration;
+ Timer CodeGenerationTime;
+
+ llvm::OwningPtr<CodeGenerator> Gen;
+
+ llvm::Module *TheModule;
+ llvm::TargetData *TheTargetData;
+
+ mutable llvm::ModuleProvider *ModuleProvider;
+ mutable FunctionPassManager *CodeGenPasses;
+ mutable PassManager *PerModulePasses;
+ mutable FunctionPassManager *PerFunctionPasses;
+
+ FunctionPassManager *getCodeGenPasses() const;
+ PassManager *getPerModulePasses() const;
+ FunctionPassManager *getPerFunctionPasses() const;
+
+ void CreatePasses();
+
+ /// AddEmitPasses - Add passes necessary to emit assembly or LLVM
+ /// IR.
+ ///
+ /// \return True on success. On failure \arg Error will be set to
+ /// a user readable error message.
+ bool AddEmitPasses(std::string &Error);
+
+ void EmitAssembly();
+
+ public:
+ BackendConsumer(BackendAction action, Diagnostic &Diags,
+ const LangOptions &langopts, const CompileOptions &compopts,
+ const std::string &infile, llvm::raw_ostream* OS) :
+ Action(action),
+ CompileOpts(compopts),
+ AsmOutStream(OS),
+ LLVMIRGeneration("LLVM IR Generation Time"),
+ CodeGenerationTime("Code Generation Time"),
+ Gen(CreateLLVMCodeGen(Diags, infile, compopts)),
+ TheModule(0), TheTargetData(0), ModuleProvider(0),
+ CodeGenPasses(0), PerModulePasses(0), PerFunctionPasses(0) {
+
+ // Enable -time-passes if -ftime-report is enabled.
+ llvm::TimePassesIsEnabled = CompileOpts.TimePasses;
+ }
+
+ ~BackendConsumer() {
+ delete TheTargetData;
+ delete ModuleProvider;
+ delete CodeGenPasses;
+ delete PerModulePasses;
+ delete PerFunctionPasses;
+ }
+
+ virtual void Initialize(ASTContext &Ctx) {
+ Context = &Ctx;
+
+ if (CompileOpts.TimePasses)
+ LLVMIRGeneration.startTimer();
+
+ Gen->Initialize(Ctx);
+
+ TheModule = Gen->GetModule();
+ ModuleProvider = new ExistingModuleProvider(TheModule);
+ TheTargetData = new llvm::TargetData(Ctx.Target.getTargetDescription());
+
+ if (CompileOpts.TimePasses)
+ LLVMIRGeneration.stopTimer();
+ }
+
+ virtual void HandleTopLevelDecl(DeclGroupRef D) {
+ PrettyStackTraceDecl CrashInfo(*D.begin(), SourceLocation(),
+ Context->getSourceManager(),
+ "LLVM IR generation of declaration");
+
+ if (CompileOpts.TimePasses)
+ LLVMIRGeneration.startTimer();
+
+ Gen->HandleTopLevelDecl(D);
+
+ if (CompileOpts.TimePasses)
+ LLVMIRGeneration.stopTimer();
+ }
+
+ virtual void HandleTranslationUnit(ASTContext &C) {
+ {
+ PrettyStackTraceString CrashInfo("Per-file LLVM IR generation");
+ if (CompileOpts.TimePasses)
+ LLVMIRGeneration.startTimer();
+
+ Gen->HandleTranslationUnit(C);
+
+ if (CompileOpts.TimePasses)
+ LLVMIRGeneration.stopTimer();
+ }
+
+ // EmitAssembly times and registers crash info itself.
+ EmitAssembly();
+
+ // Force a flush here in case we never get released.
+ if (AsmOutStream)
+ AsmOutStream->flush();
+ }
+
+ virtual void HandleTagDeclDefinition(TagDecl *D) {
+ PrettyStackTraceDecl CrashInfo(D, SourceLocation(),
+ Context->getSourceManager(),
+ "LLVM IR generation of declaration");
+ Gen->HandleTagDeclDefinition(D);
+ }
+
+ virtual void CompleteTentativeDefinition(VarDecl *D) {
+ Gen->CompleteTentativeDefinition(D);
+ }
+ };
+}
+
+FunctionPassManager *BackendConsumer::getCodeGenPasses() const {
+ if (!CodeGenPasses) {
+ CodeGenPasses = new FunctionPassManager(ModuleProvider);
+ CodeGenPasses->add(new TargetData(*TheTargetData));
+ }
+
+ return CodeGenPasses;
+}
+
+PassManager *BackendConsumer::getPerModulePasses() const {
+ if (!PerModulePasses) {
+ PerModulePasses = new PassManager();
+ PerModulePasses->add(new TargetData(*TheTargetData));
+ }
+
+ return PerModulePasses;
+}
+
+FunctionPassManager *BackendConsumer::getPerFunctionPasses() const {
+ if (!PerFunctionPasses) {
+ PerFunctionPasses = new FunctionPassManager(ModuleProvider);
+ PerFunctionPasses->add(new TargetData(*TheTargetData));
+ }
+
+ return PerFunctionPasses;
+}
+
+bool BackendConsumer::AddEmitPasses(std::string &Error) {
+ if (Action == Backend_EmitNothing)
+ return true;
+
+ if (Action == Backend_EmitBC) {
+ getPerModulePasses()->add(createBitcodeWriterPass(*AsmOutStream));
+ } else if (Action == Backend_EmitLL) {
+ getPerModulePasses()->add(createPrintModulePass(AsmOutStream));
+ } else {
+ bool Fast = CompileOpts.OptimizationLevel == 0;
+
+ // Create the TargetMachine for generating code.
+ const TargetMachineRegistry::entry *TME =
+ TargetMachineRegistry::getClosestStaticTargetForModule(*TheModule, Error);
+ if (!TME) {
+ Error = std::string("Unable to get target machine: ") + Error;
+ return false;
+ }
+
+ std::string FeaturesStr;
+ if (CompileOpts.CPU.size() || CompileOpts.Features.size()) {
+ SubtargetFeatures Features;
+ Features.setCPU(CompileOpts.CPU);
+ for (std::vector<std::string>::iterator
+ it = CompileOpts.Features.begin(),
+ ie = CompileOpts.Features.end(); it != ie; ++it)
+ Features.AddFeature(*it);
+ FeaturesStr = Features.getString();
+ }
+ TargetMachine *TM = TME->CtorFn(*TheModule, FeaturesStr);
+
+ // Set register scheduler & allocation policy.
+ RegisterScheduler::setDefault(createDefaultScheduler);
+ RegisterRegAlloc::setDefault(Fast ? createLocalRegisterAllocator :
+ createLinearScanRegisterAllocator);
+
+ // From llvm-gcc:
+ // If there are passes we have to run on the entire module, we do codegen
+ // as a separate "pass" after that happens.
+ // FIXME: This is disabled right now until bugs can be worked out. Reenable
+ // this for fast -O0 compiles!
+ FunctionPassManager *PM = getCodeGenPasses();
+ CodeGenOpt::Level OptLevel = CodeGenOpt::Default;
+
+ switch (CompileOpts.OptimizationLevel) {
+ default: break;
+ case 0: OptLevel = CodeGenOpt::None; break;
+ case 3: OptLevel = CodeGenOpt::Aggressive; break;
+ }
+
+ // Normal mode, emit a .s file by running the code generator.
+ // Note, this also adds codegenerator level optimization passes.
+ switch (TM->addPassesToEmitFile(*PM, *AsmOutStream,
+ TargetMachine::AssemblyFile, OptLevel)) {
+ default:
+ case FileModel::Error:
+ Error = "Unable to interface with target machine!\n";
+ return false;
+ case FileModel::AsmFile:
+ break;
+ }
+
+ if (TM->addPassesToEmitFileFinish(*CodeGenPasses, (MachineCodeEmitter *)0,
+ OptLevel)) {
+ Error = "Unable to interface with target machine!\n";
+ return false;
+ }
+ }
+
+ return true;
+}
+
+void BackendConsumer::CreatePasses() {
+ // In -O0 if checking is disabled, we don't even have per-function passes.
+ if (CompileOpts.VerifyModule)
+ getPerFunctionPasses()->add(createVerifierPass());
+
+ if (CompileOpts.OptimizationLevel > 0) {
+ FunctionPassManager *PM = getPerFunctionPasses();
+ PM->add(createCFGSimplificationPass());
+ if (CompileOpts.OptimizationLevel == 1)
+ PM->add(createPromoteMemoryToRegisterPass());
+ else
+ PM->add(createScalarReplAggregatesPass());
+ PM->add(createInstructionCombiningPass());
+ }
+
+ // For now we always create per module passes.
+ PassManager *PM = getPerModulePasses();
+ if (CompileOpts.OptimizationLevel > 0) {
+ if (CompileOpts.UnitAtATime)
+ PM->add(createRaiseAllocationsPass()); // call %malloc -> malloc inst
+ PM->add(createCFGSimplificationPass()); // Clean up disgusting code
+ PM->add(createPromoteMemoryToRegisterPass()); // Kill useless allocas
+ if (CompileOpts.UnitAtATime) {
+ PM->add(createGlobalOptimizerPass()); // Optimize out global vars
+ PM->add(createGlobalDCEPass()); // Remove unused fns and globs
+ PM->add(createIPConstantPropagationPass()); // IP Constant Propagation
+ PM->add(createDeadArgEliminationPass()); // Dead argument elimination
+ }
+ PM->add(createInstructionCombiningPass()); // Clean up after IPCP & DAE
+ PM->add(createCFGSimplificationPass()); // Clean up after IPCP & DAE
+ if (CompileOpts.UnitAtATime) {
+ PM->add(createPruneEHPass()); // Remove dead EH info
+ PM->add(createFunctionAttrsPass()); // Set readonly/readnone attrs
+ }
+ if (CompileOpts.InlineFunctions)
+ PM->add(createFunctionInliningPass()); // Inline small functions
+ else
+ PM->add(createAlwaysInlinerPass()); // Respect always_inline
+ if (CompileOpts.OptimizationLevel > 2)
+ PM->add(createArgumentPromotionPass()); // Scalarize uninlined fn args
+ if (CompileOpts.SimplifyLibCalls)
+ PM->add(createSimplifyLibCallsPass()); // Library Call Optimizations
+ PM->add(createInstructionCombiningPass()); // Cleanup for scalarrepl.
+ PM->add(createJumpThreadingPass()); // Thread jumps.
+ PM->add(createCFGSimplificationPass()); // Merge & remove BBs
+ PM->add(createScalarReplAggregatesPass()); // Break up aggregate allocas
+ PM->add(createInstructionCombiningPass()); // Combine silly seq's
+ PM->add(createCondPropagationPass()); // Propagate conditionals
+ PM->add(createTailCallEliminationPass()); // Eliminate tail calls
+ PM->add(createCFGSimplificationPass()); // Merge & remove BBs
+ PM->add(createReassociatePass()); // Reassociate expressions
+ PM->add(createLoopRotatePass()); // Rotate Loop
+ PM->add(createLICMPass()); // Hoist loop invariants
+ PM->add(createLoopUnswitchPass(CompileOpts.OptimizeSize ? true : false));
+// PM->add(createLoopIndexSplitPass()); // Split loop index
+ PM->add(createInstructionCombiningPass());
+ PM->add(createIndVarSimplifyPass()); // Canonicalize indvars
+ PM->add(createLoopDeletionPass()); // Delete dead loops
+ if (CompileOpts.UnrollLoops)
+ PM->add(createLoopUnrollPass()); // Unroll small loops
+ PM->add(createInstructionCombiningPass()); // Clean up after the unroller
+ PM->add(createGVNPass()); // Remove redundancies
+ PM->add(createMemCpyOptPass()); // Remove memcpy / form memset
+ PM->add(createSCCPPass()); // Constant prop with SCCP
+
+ // Run instcombine after redundancy elimination to exploit opportunities
+ // opened up by them.
+ PM->add(createInstructionCombiningPass());
+ PM->add(createCondPropagationPass()); // Propagate conditionals
+ PM->add(createDeadStoreEliminationPass()); // Delete dead stores
+ PM->add(createAggressiveDCEPass()); // Delete dead instructions
+ PM->add(createCFGSimplificationPass()); // Merge & remove BBs
+
+ if (CompileOpts.UnitAtATime) {
+ PM->add(createStripDeadPrototypesPass()); // Get rid of dead prototypes
+ PM->add(createDeadTypeEliminationPass()); // Eliminate dead types
+ }
+
+ if (CompileOpts.OptimizationLevel > 1 && CompileOpts.UnitAtATime)
+ PM->add(createConstantMergePass()); // Merge dup global constants
+ } else {
+ PM->add(createAlwaysInlinerPass());
+ }
+}
+
+/// EmitAssembly - Handle interaction with LLVM backend to generate
+/// actual machine code.
+void BackendConsumer::EmitAssembly() {
+ // Silently ignore if we weren't initialized for some reason.
+ if (!TheModule || !TheTargetData)
+ return;
+
+
+ TimeRegion Region(CompileOpts.TimePasses ? &CodeGenerationTime : 0);
+
+ // Make sure IR generation is happy with the module. This is
+ // released by the module provider.
+ Module *M = Gen->ReleaseModule();
+ if (!M) {
+ // The module has been released by IR gen on failures, do not
+ // double free.
+ ModuleProvider->releaseModule();
+ TheModule = 0;
+ return;
+ }
+
+ assert(TheModule == M && "Unexpected module change during IR generation");
+
+ CreatePasses();
+
+ std::string Error;
+ if (!AddEmitPasses(Error)) {
+ // FIXME: Don't fail this way.
+ llvm::cerr << "ERROR: " << Error << "\n";
+ ::exit(1);
+ }
+
+ // 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 = M->begin(), E = M->end(); I != E; ++I)
+ if (!I->isDeclaration())
+ PerFunctionPasses->run(*I);
+ PerFunctionPasses->doFinalization();
+ }
+
+ if (PerModulePasses) {
+ PrettyStackTraceString CrashInfo("Per-module optimization passes");
+ PerModulePasses->run(*M);
+ }
+
+ if (CodeGenPasses) {
+ PrettyStackTraceString CrashInfo("Code generation");
+ CodeGenPasses->doInitialization();
+ for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
+ if (!I->isDeclaration())
+ CodeGenPasses->run(*I);
+ CodeGenPasses->doFinalization();
+ }
+}
+
+ASTConsumer *clang::CreateBackendConsumer(BackendAction Action,
+ Diagnostic &Diags,
+ const LangOptions &LangOpts,
+ const CompileOptions &CompileOpts,
+ const std::string& InFile,
+ llvm::raw_ostream* OS) {
+ return new BackendConsumer(Action, Diags, LangOpts, CompileOpts, InFile, OS);
+}
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