1 files changed, 416 insertions, 0 deletions
diff --git a/contrib/llvm/tools/lto/LTOCodeGenerator.cpp b/contrib/llvm/tools/lto/LTOCodeGenerator.cpp
new file mode 100644
index 0000000..59e8405
--- /dev/null
+++ b/contrib/llvm/tools/lto/LTOCodeGenerator.cpp
@@ -0,0 +1,416 @@
+//===-LTOCodeGenerator.cpp - LLVM Link Time Optimizer ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+// This file implements the Link Time Optimization library. This library is 
+// intended to be used by linker to optimize code at link time.
+//
+//===----------------------------------------------------------------------===//
+
+#include "LTOModule.h"
+#include "LTOCodeGenerator.h"
+
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Linker.h"
+#include "llvm/LLVMContext.h"
+#include "llvm/Module.h"
+#include "llvm/PassManager.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/Analysis/Passes.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/Target/Mangler.h"
+#include "llvm/Target/SubtargetFeature.h"
+#include "llvm/Target/TargetOptions.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetRegistry.h"
+#include "llvm/Target/TargetSelect.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/FormattedStream.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/StandardPasses.h"
+#include "llvm/Support/SystemUtils.h"
+#include "llvm/System/Host.h"
+#include "llvm/System/Program.h"
+#include "llvm/System/Signals.h"
+#include "llvm/Config/config.h"
+#include <cstdlib>
+#include <unistd.h>
+#include <fcntl.h>
+
+
+using namespace llvm;
+
+static cl::opt<bool> DisableInline("disable-inlining",
+  cl::desc("Do not run the inliner pass"));
+
+
+const char* LTOCodeGenerator::getVersionString()
+{
+#ifdef LLVM_VERSION_INFO
+    return PACKAGE_NAME " version " PACKAGE_VERSION ", " LLVM_VERSION_INFO;
+#else
+    return PACKAGE_NAME " version " PACKAGE_VERSION;
+#endif
+}
+
+
+LTOCodeGenerator::LTOCodeGenerator() 
+    : _context(getGlobalContext()),
+      _linker("LinkTimeOptimizer", "ld-temp.o", _context), _target(NULL),
+      _emitDwarfDebugInfo(false), _scopeRestrictionsDone(false),
+      _codeModel(LTO_CODEGEN_PIC_MODEL_DYNAMIC),
+      _nativeObjectFile(NULL), _assemblerPath(NULL)
+{
+    InitializeAllTargets();
+    InitializeAllAsmPrinters();
+}
+
+LTOCodeGenerator::~LTOCodeGenerator()
+{
+    delete _target;
+    delete _nativeObjectFile;
+}
+
+
+
+bool LTOCodeGenerator::addModule(LTOModule* mod, std::string& errMsg)
+{
+    return _linker.LinkInModule(mod->getLLVVMModule(), &errMsg);
+}
+    
+
+bool LTOCodeGenerator::setDebugInfo(lto_debug_model debug, std::string& errMsg)
+{
+    switch (debug) {
+        case LTO_DEBUG_MODEL_NONE:
+            _emitDwarfDebugInfo = false;
+            return false;
+            
+        case LTO_DEBUG_MODEL_DWARF:
+            _emitDwarfDebugInfo = true;
+            return false;
+    }
+    errMsg = "unknown debug format";
+    return true;
+}
+
+
+bool LTOCodeGenerator::setCodePICModel(lto_codegen_model model, 
+                                       std::string& errMsg)
+{
+    switch (model) {
+        case LTO_CODEGEN_PIC_MODEL_STATIC:
+        case LTO_CODEGEN_PIC_MODEL_DYNAMIC:
+        case LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC:
+            _codeModel = model;
+            return false;
+    }
+    errMsg = "unknown pic model";
+    return true;
+}
+
+void LTOCodeGenerator::setAssemblerPath(const char* path)
+{
+    if ( _assemblerPath )
+        delete _assemblerPath;
+    _assemblerPath = new sys::Path(path);
+}
+
+void LTOCodeGenerator::addMustPreserveSymbol(const char* sym)
+{
+    _mustPreserveSymbols[sym] = 1;
+}
+
+
+bool LTOCodeGenerator::writeMergedModules(const char *path,
+                                          std::string &errMsg) {
+  if (determineTarget(errMsg))
+    return true;
+
+  // mark which symbols can not be internalized 
+  applyScopeRestrictions();
+
+  // create output file
+  std::string ErrInfo;
+  raw_fd_ostream Out(path, ErrInfo,
+                     raw_fd_ostream::F_Binary);
+  if (!ErrInfo.empty()) {
+    errMsg = "could not open bitcode file for writing: ";
+    errMsg += path;
+    return true;
+  }
+    
+  // write bitcode to it
+  WriteBitcodeToFile(_linker.getModule(), Out);
+  
+  if (Out.has_error()) {
+    errMsg = "could not write bitcode file: ";
+    errMsg += path;
+    return true;
+  }
+  
+  return false;
+}
+
+
+const void* LTOCodeGenerator::compile(size_t* length, std::string& errMsg)
+{
+    // make unique temp .s file to put generated assembly code
+    sys::Path uniqueAsmPath("lto-llvm.s");
+    if ( uniqueAsmPath.createTemporaryFileOnDisk(true, &errMsg) )
+        return NULL;
+    sys::RemoveFileOnSignal(uniqueAsmPath);
+       
+    // generate assembly code
+    bool genResult = false;
+    {
+      raw_fd_ostream asmFD(uniqueAsmPath.c_str(), errMsg);
+      formatted_raw_ostream asmFile(asmFD);
+      if (!errMsg.empty())
+        return NULL;
+      genResult = this->generateAssemblyCode(asmFile, errMsg);
+    }
+    if ( genResult ) {
+        if ( uniqueAsmPath.exists() )
+            uniqueAsmPath.eraseFromDisk();
+        return NULL;
+    }
+    
+    // make unique temp .o file to put generated object file
+    sys::PathWithStatus uniqueObjPath("lto-llvm.o");
+    if ( uniqueObjPath.createTemporaryFileOnDisk(true, &errMsg) ) {
+        if ( uniqueAsmPath.exists() )
+            uniqueAsmPath.eraseFromDisk();
+        return NULL;
+    }
+    sys::RemoveFileOnSignal(uniqueObjPath);
+
+    // assemble the assembly code
+    const std::string& uniqueObjStr = uniqueObjPath.str();
+    bool asmResult = this->assemble(uniqueAsmPath.str(), uniqueObjStr, errMsg);
+    if ( !asmResult ) {
+        // remove old buffer if compile() called twice
+        delete _nativeObjectFile;
+        
+        // read .o file into memory buffer
+        _nativeObjectFile = MemoryBuffer::getFile(uniqueObjStr.c_str(),&errMsg);
+    }
+
+    // remove temp files
+    uniqueAsmPath.eraseFromDisk();
+    uniqueObjPath.eraseFromDisk();
+
+    // return buffer, unless error
+    if ( _nativeObjectFile == NULL )
+        return NULL;
+    *length = _nativeObjectFile->getBufferSize();
+    return _nativeObjectFile->getBufferStart();
+}
+
+
+bool LTOCodeGenerator::assemble(const std::string& asmPath, 
+                                const std::string& objPath, std::string& errMsg)
+{
+    sys::Path tool;
+    bool needsCompilerOptions = true;
+    if ( _assemblerPath ) {
+        tool = *_assemblerPath;
+        needsCompilerOptions = false;
+    } else {
+        // find compiler driver
+        tool = sys::Program::FindProgramByName("gcc");
+        if ( tool.isEmpty() ) {
+            errMsg = "can't locate gcc";
+            return true;
+        }
+    }
+
+    // build argument list
+    std::vector<const char*> args;
+    llvm::Triple targetTriple(_linker.getModule()->getTargetTriple());
+    const char *arch = targetTriple.getArchNameForAssembler();
+
+    args.push_back(tool.c_str());
+
+    if (targetTriple.getOS() == Triple::Darwin) {
+        // darwin specific command line options
+        if (arch != NULL) {
+            args.push_back("-arch");
+            args.push_back(arch);
+        }
+        // add -static to assembler command line when code model requires
+        if ( (_assemblerPath != NULL) &&
+            (_codeModel == LTO_CODEGEN_PIC_MODEL_STATIC) )
+            args.push_back("-static");
+    }
+    if ( needsCompilerOptions ) {
+        args.push_back("-c");
+        args.push_back("-x");
+        args.push_back("assembler");
+    }
+    args.push_back("-o");
+    args.push_back(objPath.c_str());
+    args.push_back(asmPath.c_str());
+    args.push_back(0);
+
+    // invoke assembler
+    if ( sys::Program::ExecuteAndWait(tool, &args[0], 0, 0, 0, 0, &errMsg) ) {
+        errMsg = "error in assembly";    
+        return true;
+    }
+    return false; // success
+}
+
+
+
+bool LTOCodeGenerator::determineTarget(std::string& errMsg)
+{
+    if ( _target == NULL ) {
+        std::string Triple = _linker.getModule()->getTargetTriple();
+        if (Triple.empty())
+          Triple = sys::getHostTriple();
+
+        // create target machine from info for merged modules
+        const Target *march = TargetRegistry::lookupTarget(Triple, errMsg);
+        if ( march == NULL )
+            return true;
+
+        // The relocation model is actually a static member of TargetMachine
+        // and needs to be set before the TargetMachine is instantiated.
+        switch( _codeModel ) {
+        case LTO_CODEGEN_PIC_MODEL_STATIC:
+            TargetMachine::setRelocationModel(Reloc::Static);
+            break;
+        case LTO_CODEGEN_PIC_MODEL_DYNAMIC:
+            TargetMachine::setRelocationModel(Reloc::PIC_);
+            break;
+        case LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC:
+            TargetMachine::setRelocationModel(Reloc::DynamicNoPIC);
+            break;
+        }
+
+        // construct LTModule, hand over ownership of module and target
+        SubtargetFeatures Features;
+        Features.getDefaultSubtargetFeatures("" /* cpu */, llvm::Triple(Triple));
+        std::string FeatureStr = Features.getString();
+        _target = march->createTargetMachine(Triple, FeatureStr);
+    }
+    return false;
+}
+
+void LTOCodeGenerator::applyScopeRestrictions() {
+  if (_scopeRestrictionsDone) return;
+  Module *mergedModule = _linker.getModule();
+
+  // Start off with a verification pass.
+  PassManager passes;
+  passes.add(createVerifierPass());
+
+  // mark which symbols can not be internalized 
+  if (!_mustPreserveSymbols.empty()) {
+    MCContext Context(*_target->getMCAsmInfo());
+    Mangler mangler(Context, *_target->getTargetData());
+    std::vector<const char*> mustPreserveList;
+    for (Module::iterator f = mergedModule->begin(),
+         e = mergedModule->end(); f != e; ++f) {
+      if (!f->isDeclaration() &&
+          _mustPreserveSymbols.count(mangler.getNameWithPrefix(f)))
+        mustPreserveList.push_back(::strdup(f->getNameStr().c_str()));
+    }
+    for (Module::global_iterator v = mergedModule->global_begin(), 
+         e = mergedModule->global_end(); v !=  e; ++v) {
+      if (!v->isDeclaration() &&
+          _mustPreserveSymbols.count(mangler.getNameWithPrefix(v)))
+        mustPreserveList.push_back(::strdup(v->getNameStr().c_str()));
+    }
+    passes.add(createInternalizePass(mustPreserveList));
+  }
+  
+  // apply scope restrictions
+  passes.run(*mergedModule);
+  
+  _scopeRestrictionsDone = true;
+}
+
+/// Optimize merged modules using various IPO passes
+bool LTOCodeGenerator::generateAssemblyCode(formatted_raw_ostream& out,
+                                            std::string& errMsg)
+{
+    if ( this->determineTarget(errMsg) ) 
+        return true;
+
+    // mark which symbols can not be internalized 
+    this->applyScopeRestrictions();
+
+    Module* mergedModule = _linker.getModule();
+
+    // if options were requested, set them
+    if ( !_codegenOptions.empty() )
+        cl::ParseCommandLineOptions(_codegenOptions.size(), 
+                                    const_cast<char **>(&_codegenOptions[0]));
+
+    // Instantiate the pass manager to organize the passes.
+    PassManager passes;
+
+    // Start off with a verification pass.
+    passes.add(createVerifierPass());
+
+    // Add an appropriate TargetData instance for this module...
+    passes.add(new TargetData(*_target->getTargetData()));
+    
+    createStandardLTOPasses(&passes, /*Internalize=*/ false, !DisableInline,
+                            /*VerifyEach=*/ false);
+
+    // Make sure everything is still good.
+    passes.add(createVerifierPass());
+
+    FunctionPassManager* codeGenPasses = new FunctionPassManager(mergedModule);
+
+    codeGenPasses->add(new TargetData(*_target->getTargetData()));
+
+    if (_target->addPassesToEmitFile(*codeGenPasses, out,
+                                     TargetMachine::CGFT_AssemblyFile,
+                                     CodeGenOpt::Aggressive)) {
+      errMsg = "target file type not supported";
+      return true;
+    }
+
+    // Run our queue of passes all at once now, efficiently.
+    passes.run(*mergedModule);
+
+    // Run the code generator, and write assembly file
+    codeGenPasses->doInitialization();
+
+    for (Module::iterator
+           it = mergedModule->begin(), e = mergedModule->end(); it != e; ++it)
+      if (!it->isDeclaration())
+        codeGenPasses->run(*it);
+
+    codeGenPasses->doFinalization();
+
+    return false; // success
+}
+
+
+/// Optimize merged modules using various IPO passes
+void LTOCodeGenerator::setCodeGenDebugOptions(const char* options)
+{
+    for (std::pair<StringRef, StringRef> o = getToken(options);
+         !o.first.empty(); o = getToken(o.second)) {
+        // ParseCommandLineOptions() expects argv[0] to be program name.
+        // Lazily add that.
+        if ( _codegenOptions.empty() ) 
+            _codegenOptions.push_back("libLTO");
+        _codegenOptions.push_back(strdup(o.first.str().c_str()));
+    }
+}