llvm-6502/tools/llc/llc.cpp
2010-12-02 23:03:57 +00:00

349 lines
11 KiB
C++

//===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This is the llc code generator driver. It provides a convenient
// command-line interface for generating native assembly-language code
// or C code, given LLVM bitcode.
//
//===----------------------------------------------------------------------===//
#include "llvm/LLVMContext.h"
#include "llvm/Module.h"
#include "llvm/PassManager.h"
#include "llvm/Pass.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Support/IRReader.h"
#include "llvm/CodeGen/LinkAllAsmWriterComponents.h"
#include "llvm/CodeGen/LinkAllCodegenComponents.h"
#include "llvm/Config/config.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/PluginLoader.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/ToolOutputFile.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/Signals.h"
#include "llvm/Target/SubtargetFeature.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetRegistry.h"
#include "llvm/Target/TargetSelect.h"
#include <memory>
using namespace llvm;
// General options for llc. Other pass-specific options are specified
// within the corresponding llc passes, and target-specific options
// and back-end code generation options are specified with the target machine.
//
static cl::opt<std::string>
InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
static cl::opt<std::string>
OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
// Determine optimization level.
static cl::opt<char>
OptLevel("O",
cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
"(default = '-O2')"),
cl::Prefix,
cl::ZeroOrMore,
cl::init(' '));
static cl::opt<std::string>
TargetTriple("mtriple", cl::desc("Override target triple for module"));
static cl::opt<std::string>
MArch("march", cl::desc("Architecture to generate code for (see --version)"));
static cl::opt<std::string>
MCPU("mcpu",
cl::desc("Target a specific cpu type (-mcpu=help for details)"),
cl::value_desc("cpu-name"),
cl::init(""));
static cl::list<std::string>
MAttrs("mattr",
cl::CommaSeparated,
cl::desc("Target specific attributes (-mattr=help for details)"),
cl::value_desc("a1,+a2,-a3,..."));
static cl::opt<bool>
RelaxAll("mc-relax-all",
cl::desc("When used with filetype=obj, "
"relax all fixups in the emitted object file"));
cl::opt<TargetMachine::CodeGenFileType>
FileType("filetype", cl::init(TargetMachine::CGFT_AssemblyFile),
cl::desc("Choose a file type (not all types are supported by all targets):"),
cl::values(
clEnumValN(TargetMachine::CGFT_AssemblyFile, "asm",
"Emit an assembly ('.s') file"),
clEnumValN(TargetMachine::CGFT_ObjectFile, "obj",
"Emit a native object ('.o') file [experimental]"),
clEnumValN(TargetMachine::CGFT_Null, "null",
"Emit nothing, for performance testing"),
clEnumValEnd));
cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
cl::desc("Do not verify input module"));
cl::opt<bool> DisableDotLoc("disable-dot-loc", cl::Hidden,
cl::desc("Do not use .loc entries"));
static cl::opt<bool>
DisableRedZone("disable-red-zone",
cl::desc("Do not emit code that uses the red zone."),
cl::init(false));
static cl::opt<bool>
NoImplicitFloats("no-implicit-float",
cl::desc("Don't generate implicit floating point instructions (x86-only)"),
cl::init(false));
// GetFileNameRoot - Helper function to get the basename of a filename.
static inline std::string
GetFileNameRoot(const std::string &InputFilename) {
std::string IFN = InputFilename;
std::string outputFilename;
int Len = IFN.length();
if ((Len > 2) &&
IFN[Len-3] == '.' &&
((IFN[Len-2] == 'b' && IFN[Len-1] == 'c') ||
(IFN[Len-2] == 'l' && IFN[Len-1] == 'l'))) {
outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
} else {
outputFilename = IFN;
}
return outputFilename;
}
static tool_output_file *GetOutputStream(const char *TargetName,
Triple::OSType OS,
const char *ProgName) {
// If we don't yet have an output filename, make one.
if (OutputFilename.empty()) {
if (InputFilename == "-")
OutputFilename = "-";
else {
OutputFilename = GetFileNameRoot(InputFilename);
switch (FileType) {
default: assert(0 && "Unknown file type");
case TargetMachine::CGFT_AssemblyFile:
if (TargetName[0] == 'c') {
if (TargetName[1] == 0)
OutputFilename += ".cbe.c";
else if (TargetName[1] == 'p' && TargetName[2] == 'p')
OutputFilename += ".cpp";
else
OutputFilename += ".s";
} else
OutputFilename += ".s";
break;
case TargetMachine::CGFT_ObjectFile:
if (OS == Triple::Win32)
OutputFilename += ".obj";
else
OutputFilename += ".o";
break;
case TargetMachine::CGFT_Null:
OutputFilename += ".null";
break;
}
}
}
// Decide if we need "binary" output.
bool Binary = false;
switch (FileType) {
default: assert(0 && "Unknown file type");
case TargetMachine::CGFT_AssemblyFile:
break;
case TargetMachine::CGFT_ObjectFile:
case TargetMachine::CGFT_Null:
Binary = true;
break;
}
// Open the file.
std::string error;
unsigned OpenFlags = 0;
if (Binary) OpenFlags |= raw_fd_ostream::F_Binary;
tool_output_file *FDOut = new tool_output_file(OutputFilename.c_str(), error,
OpenFlags);
if (!error.empty()) {
errs() << error << '\n';
delete FDOut;
return 0;
}
return FDOut;
}
// main - Entry point for the llc compiler.
//
int main(int argc, char **argv) {
sys::PrintStackTraceOnErrorSignal();
PrettyStackTraceProgram X(argc, argv);
// Enable debug stream buffering.
EnableDebugBuffering = true;
LLVMContext &Context = getGlobalContext();
llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
// Initialize targets first, so that --version shows registered targets.
InitializeAllTargets();
InitializeAllAsmPrinters();
InitializeAllAsmParsers();
cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
// Load the module to be compiled...
SMDiagnostic Err;
std::auto_ptr<Module> M;
M.reset(ParseIRFile(InputFilename, Err, Context));
if (M.get() == 0) {
Err.Print(argv[0], errs());
return 1;
}
Module &mod = *M.get();
// If we are supposed to override the target triple, do so now.
if (!TargetTriple.empty())
mod.setTargetTriple(Triple::normalize(TargetTriple));
Triple TheTriple(mod.getTargetTriple());
if (TheTriple.getTriple().empty())
TheTriple.setTriple(sys::getHostTriple());
// Allocate target machine. First, check whether the user has explicitly
// specified an architecture to compile for. If so we have to look it up by
// name, because it might be a backend that has no mapping to a target triple.
const Target *TheTarget = 0;
if (!MArch.empty()) {
for (TargetRegistry::iterator it = TargetRegistry::begin(),
ie = TargetRegistry::end(); it != ie; ++it) {
if (MArch == it->getName()) {
TheTarget = &*it;
break;
}
}
if (!TheTarget) {
errs() << argv[0] << ": error: invalid target '" << MArch << "'.\n";
return 1;
}
// Adjust the triple to match (if known), otherwise stick with the
// module/host triple.
Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch);
if (Type != Triple::UnknownArch)
TheTriple.setArch(Type);
} else {
std::string Err;
TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Err);
if (TheTarget == 0) {
errs() << argv[0] << ": error auto-selecting target for module '"
<< Err << "'. Please use the -march option to explicitly "
<< "pick a target.\n";
return 1;
}
}
// Package up features to be passed to target/subtarget
std::string FeaturesStr;
if (MCPU.size() || MAttrs.size()) {
SubtargetFeatures Features;
Features.setCPU(MCPU);
for (unsigned i = 0; i != MAttrs.size(); ++i)
Features.AddFeature(MAttrs[i]);
FeaturesStr = Features.getString();
}
std::auto_ptr<TargetMachine>
target(TheTarget->createTargetMachine(TheTriple.getTriple(), FeaturesStr));
assert(target.get() && "Could not allocate target machine!");
TargetMachine &Target = *target.get();
if (DisableDotLoc)
Target.setMCUseLoc(false);
if (TheTriple.getOS() == Triple::Darwin) {
switch (TheTriple.getDarwinMajorNumber()) {
case 7:
case 8:
case 9:
// disable .loc support for older darwin OS.
Target.setMCUseLoc(false);
break;
default:
break;
}
}
// Figure out where we are going to send the output...
OwningPtr<tool_output_file> Out
(GetOutputStream(TheTarget->getName(), TheTriple.getOS(), argv[0]));
if (!Out) return 1;
CodeGenOpt::Level OLvl = CodeGenOpt::Default;
switch (OptLevel) {
default:
errs() << argv[0] << ": invalid optimization level.\n";
return 1;
case ' ': break;
case '0': OLvl = CodeGenOpt::None; break;
case '1': OLvl = CodeGenOpt::Less; break;
case '2': OLvl = CodeGenOpt::Default; break;
case '3': OLvl = CodeGenOpt::Aggressive; break;
}
// Build up all of the passes that we want to do to the module.
PassManager PM;
// Add the target data from the target machine, if it exists, or the module.
if (const TargetData *TD = Target.getTargetData())
PM.add(new TargetData(*TD));
else
PM.add(new TargetData(&mod));
// Override default to generate verbose assembly.
Target.setAsmVerbosityDefault(true);
if (RelaxAll) {
if (FileType != TargetMachine::CGFT_ObjectFile)
errs() << argv[0]
<< ": warning: ignoring -mc-relax-all because filetype != obj";
else
Target.setMCRelaxAll(true);
}
{
formatted_raw_ostream FOS(Out->os());
// Ask the target to add backend passes as necessary.
if (Target.addPassesToEmitFile(PM, FOS, FileType, OLvl, NoVerify)) {
errs() << argv[0] << ": target does not support generation of this"
<< " file type!\n";
return 1;
}
PM.run(mod);
}
// Declare success.
Out->keep();
return 0;
}