Update clang to r108243.

1 files changed, 339 insertions, 0 deletions

diff --git a/lib/CodeGen/BackendUtil.cpp b/lib/CodeGen/BackendUtil.cpp
new file mode 100644
index 0000000..69efe43
--- /dev/null
+++ b/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);
+}