mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-15 04:30:12 +00:00
988fdc5f28
materialise them in LTO. I observed a ~0.5-1% speedup for an LTO link of opt. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143784 91177308-0d34-0410-b5e6-96231b3b80d8
432 lines
13 KiB
C++
432 lines
13 KiB
C++
//===-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/Analysis/Verifier.h"
|
|
#include "llvm/Bitcode/ReaderWriter.h"
|
|
#include "llvm/MC/MCAsmInfo.h"
|
|
#include "llvm/MC/MCContext.h"
|
|
#include "llvm/MC/SubtargetFeature.h"
|
|
#include "llvm/Target/Mangler.h"
|
|
#include "llvm/Target/TargetOptions.h"
|
|
#include "llvm/Target/TargetData.h"
|
|
#include "llvm/Target/TargetMachine.h"
|
|
#include "llvm/Target/TargetRegisterInfo.h"
|
|
#include "llvm/Support/CommandLine.h"
|
|
#include "llvm/Support/FormattedStream.h"
|
|
#include "llvm/Support/MemoryBuffer.h"
|
|
#include "llvm/Support/SystemUtils.h"
|
|
#include "llvm/Support/ToolOutputFile.h"
|
|
#include "llvm/Support/Host.h"
|
|
#include "llvm/Support/Program.h"
|
|
#include "llvm/Support/Signals.h"
|
|
#include "llvm/Support/TargetRegistry.h"
|
|
#include "llvm/Support/TargetSelect.h"
|
|
#include "llvm/Support/system_error.h"
|
|
#include "llvm/Config/config.h"
|
|
#include "llvm/Transforms/IPO.h"
|
|
#include "llvm/Transforms/IPO/PassManagerBuilder.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)
|
|
{
|
|
InitializeAllTargets();
|
|
InitializeAllTargetMCs();
|
|
InitializeAllAsmPrinters();
|
|
}
|
|
|
|
LTOCodeGenerator::~LTOCodeGenerator()
|
|
{
|
|
delete _target;
|
|
delete _nativeObjectFile;
|
|
}
|
|
|
|
|
|
|
|
bool LTOCodeGenerator::addModule(LTOModule* mod, std::string& errMsg)
|
|
{
|
|
bool ret = _linker.LinkInModule(mod->getLLVVMModule(), &errMsg);
|
|
|
|
const std::vector<const char*> &undefs = mod->getAsmUndefinedRefs();
|
|
for (int i = 0, e = undefs.size(); i != e; ++i)
|
|
_asmUndefinedRefs[undefs[i]] = 1;
|
|
|
|
return ret;
|
|
}
|
|
|
|
|
|
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::setCpu(const char* mCpu)
|
|
{
|
|
_mCpu = mCpu;
|
|
}
|
|
|
|
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;
|
|
tool_output_file 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.os());
|
|
Out.os().close();
|
|
|
|
if (Out.os().has_error()) {
|
|
errMsg = "could not write bitcode file: ";
|
|
errMsg += path;
|
|
Out.os().clear_error();
|
|
return true;
|
|
}
|
|
|
|
Out.keep();
|
|
return false;
|
|
}
|
|
|
|
|
|
bool LTOCodeGenerator::compile_to_file(const char** name, std::string& errMsg)
|
|
{
|
|
// make unique temp .o file to put generated object file
|
|
sys::PathWithStatus uniqueObjPath("lto-llvm.o");
|
|
if ( uniqueObjPath.createTemporaryFileOnDisk(false, &errMsg) ) {
|
|
uniqueObjPath.eraseFromDisk();
|
|
return true;
|
|
}
|
|
sys::RemoveFileOnSignal(uniqueObjPath);
|
|
|
|
// generate object file
|
|
bool genResult = false;
|
|
tool_output_file objFile(uniqueObjPath.c_str(), errMsg);
|
|
if (!errMsg.empty())
|
|
return true;
|
|
genResult = this->generateObjectFile(objFile.os(), errMsg);
|
|
objFile.os().close();
|
|
if (objFile.os().has_error()) {
|
|
objFile.os().clear_error();
|
|
return true;
|
|
}
|
|
objFile.keep();
|
|
if ( genResult ) {
|
|
uniqueObjPath.eraseFromDisk();
|
|
return true;
|
|
}
|
|
|
|
_nativeObjectPath = uniqueObjPath.str();
|
|
*name = _nativeObjectPath.c_str();
|
|
return false;
|
|
}
|
|
|
|
const void* LTOCodeGenerator::compile(size_t* length, std::string& errMsg)
|
|
{
|
|
const char *name;
|
|
if (compile_to_file(&name, errMsg))
|
|
return NULL;
|
|
|
|
// remove old buffer if compile() called twice
|
|
delete _nativeObjectFile;
|
|
|
|
// read .o file into memory buffer
|
|
OwningPtr<MemoryBuffer> BuffPtr;
|
|
if (error_code ec = MemoryBuffer::getFile(name, BuffPtr, -1, false)) {
|
|
errMsg = ec.message();
|
|
return NULL;
|
|
}
|
|
_nativeObjectFile = BuffPtr.take();
|
|
|
|
// remove temp files
|
|
sys::Path(_nativeObjectPath).eraseFromDisk();
|
|
|
|
// return buffer, unless error
|
|
if ( _nativeObjectFile == NULL )
|
|
return NULL;
|
|
*length = _nativeObjectFile->getBufferSize();
|
|
return _nativeObjectFile->getBufferStart();
|
|
}
|
|
|
|
bool LTOCodeGenerator::determineTarget(std::string& errMsg)
|
|
{
|
|
if ( _target == NULL ) {
|
|
std::string Triple = _linker.getModule()->getTargetTriple();
|
|
if (Triple.empty())
|
|
Triple = sys::getDefaultTargetTriple();
|
|
|
|
// 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.
|
|
Reloc::Model RelocModel = Reloc::Default;
|
|
switch( _codeModel ) {
|
|
case LTO_CODEGEN_PIC_MODEL_STATIC:
|
|
RelocModel = Reloc::Static;
|
|
break;
|
|
case LTO_CODEGEN_PIC_MODEL_DYNAMIC:
|
|
RelocModel = Reloc::PIC_;
|
|
break;
|
|
case LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC:
|
|
RelocModel = Reloc::DynamicNoPIC;
|
|
break;
|
|
}
|
|
|
|
// construct LTOModule, hand over ownership of module and target
|
|
SubtargetFeatures Features;
|
|
Features.getDefaultSubtargetFeatures(llvm::Triple(Triple));
|
|
std::string FeatureStr = Features.getString();
|
|
_target = march->createTargetMachine(Triple, _mCpu, FeatureStr,
|
|
RelocModel);
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void LTOCodeGenerator::applyRestriction(GlobalValue &GV,
|
|
std::vector<const char*> &mustPreserveList,
|
|
SmallPtrSet<GlobalValue*, 8> &asmUsed,
|
|
Mangler &mangler) {
|
|
SmallString<64> Buffer;
|
|
mangler.getNameWithPrefix(Buffer, &GV, false);
|
|
|
|
if (GV.isDeclaration())
|
|
return;
|
|
if (_mustPreserveSymbols.count(Buffer))
|
|
mustPreserveList.push_back(GV.getName().data());
|
|
if (_asmUndefinedRefs.count(Buffer))
|
|
asmUsed.insert(&GV);
|
|
}
|
|
|
|
static void findUsedValues(GlobalVariable *LLVMUsed,
|
|
SmallPtrSet<GlobalValue*, 8> &UsedValues) {
|
|
if (LLVMUsed == 0) return;
|
|
|
|
ConstantArray *Inits = dyn_cast<ConstantArray>(LLVMUsed->getInitializer());
|
|
if (Inits == 0) return;
|
|
|
|
for (unsigned i = 0, e = Inits->getNumOperands(); i != e; ++i)
|
|
if (GlobalValue *GV =
|
|
dyn_cast<GlobalValue>(Inits->getOperand(i)->stripPointerCasts()))
|
|
UsedValues.insert(GV);
|
|
}
|
|
|
|
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
|
|
MCContext Context(*_target->getMCAsmInfo(), *_target->getRegisterInfo(), NULL);
|
|
Mangler mangler(Context, *_target->getTargetData());
|
|
std::vector<const char*> mustPreserveList;
|
|
SmallPtrSet<GlobalValue*, 8> asmUsed;
|
|
|
|
for (Module::iterator f = mergedModule->begin(),
|
|
e = mergedModule->end(); f != e; ++f)
|
|
applyRestriction(*f, mustPreserveList, asmUsed, mangler);
|
|
for (Module::global_iterator v = mergedModule->global_begin(),
|
|
e = mergedModule->global_end(); v != e; ++v)
|
|
applyRestriction(*v, mustPreserveList, asmUsed, mangler);
|
|
for (Module::alias_iterator a = mergedModule->alias_begin(),
|
|
e = mergedModule->alias_end(); a != e; ++a)
|
|
applyRestriction(*a, mustPreserveList, asmUsed, mangler);
|
|
|
|
GlobalVariable *LLVMCompilerUsed =
|
|
mergedModule->getGlobalVariable("llvm.compiler.used");
|
|
findUsedValues(LLVMCompilerUsed, asmUsed);
|
|
if (LLVMCompilerUsed)
|
|
LLVMCompilerUsed->eraseFromParent();
|
|
|
|
llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(_context);
|
|
std::vector<Constant*> asmUsed2;
|
|
for (SmallPtrSet<GlobalValue*, 16>::const_iterator i = asmUsed.begin(),
|
|
e = asmUsed.end(); i !=e; ++i) {
|
|
GlobalValue *GV = *i;
|
|
Constant *c = ConstantExpr::getBitCast(GV, i8PTy);
|
|
asmUsed2.push_back(c);
|
|
}
|
|
|
|
llvm::ArrayType *ATy = llvm::ArrayType::get(i8PTy, asmUsed2.size());
|
|
LLVMCompilerUsed =
|
|
new llvm::GlobalVariable(*mergedModule, ATy, false,
|
|
llvm::GlobalValue::AppendingLinkage,
|
|
llvm::ConstantArray::get(ATy, asmUsed2),
|
|
"llvm.compiler.used");
|
|
|
|
LLVMCompilerUsed->setSection("llvm.metadata");
|
|
|
|
passes.add(createInternalizePass(mustPreserveList));
|
|
|
|
// apply scope restrictions
|
|
passes.run(*mergedModule);
|
|
|
|
_scopeRestrictionsDone = true;
|
|
}
|
|
|
|
/// Optimize merged modules using various IPO passes
|
|
bool LTOCodeGenerator::generateObjectFile(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()));
|
|
|
|
PassManagerBuilder().populateLTOPassManager(passes, /*Internalize=*/ false,
|
|
!DisableInline);
|
|
|
|
// Make sure everything is still good.
|
|
passes.add(createVerifierPass());
|
|
|
|
FunctionPassManager *codeGenPasses = new FunctionPassManager(mergedModule);
|
|
|
|
codeGenPasses->add(new TargetData(*_target->getTargetData()));
|
|
|
|
formatted_raw_ostream Out(out);
|
|
|
|
if (_target->addPassesToEmitFile(*codeGenPasses, Out,
|
|
TargetMachine::CGFT_ObjectFile,
|
|
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();
|
|
delete codeGenPasses;
|
|
|
|
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()));
|
|
}
|
|
}
|