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//===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and 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 bytecode.
//
//===----------------------------------------------------------------------===//
#include "llvm/Bytecode/Reader.h"
#include "llvm/Target/TargetMachineImpls.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Module.h"
#include "llvm/PassManager.h"
#include "llvm/Pass.h"
#include "Support/CommandLine.h"
#include "Support/Signals.h"
#include <memory>
#include <fstream>
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 bytecode>"), cl::init("-"));
static cl::opt<std::string>
OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
static cl::opt<bool> Force("f", cl::desc("Overwrite output files"));
enum ArchName { noarch, X86, SparcV9, PowerPC, CBackend };
static cl::opt<ArchName>
Arch("march", cl::desc("Architecture to generate assembly for:"), cl::Prefix,
cl::values(clEnumValN(X86, "x86", " IA-32 (Pentium and above)"),
clEnumValN(SparcV9, "sparcv9", " SPARC V9"),
clEnumValN(PowerPC, "powerpc", " PowerPC (experimental)"),
clEnumValN(CBackend, "c", " C backend"),
0),
cl::init(noarch));
// 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') {
outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
} else {
outputFilename = IFN;
}
return outputFilename;
}
// main - Entry point for the llc compiler.
//
int main(int argc, char **argv) {
cl::ParseCommandLineOptions(argc, argv, " llvm system compiler\n");
PrintStackTraceOnErrorSignal();
// Load the module to be compiled...
std::auto_ptr<Module> M(ParseBytecodeFile(InputFilename));
if (M.get() == 0) {
std::cerr << argv[0] << ": bytecode didn't read correctly.\n";
return 1;
}
Module &mod = *M.get();
// Allocate target machine. First, check whether the user has
// explicitly specified an architecture to compile for.
TargetMachine* (*TargetMachineAllocator)(const Module&,
IntrinsicLowering *) = 0;
switch (Arch) {
case CBackend:
TargetMachineAllocator = allocateCTargetMachine;
break;
case X86:
TargetMachineAllocator = allocateX86TargetMachine;
break;
case SparcV9:
TargetMachineAllocator = allocateSparcV9TargetMachine;
break;
case PowerPC:
TargetMachineAllocator = allocatePowerPCTargetMachine;
break;
default:
// Decide what the default target machine should be, by looking at
// the module. This heuristic (ILP32, LE -> IA32; LP64, BE ->
// SPARCV9) is kind of gross, but it will work until we have more
// sophisticated target information to work from.
if (mod.getEndianness() == Module::LittleEndian &&
mod.getPointerSize() == Module::Pointer32) {
TargetMachineAllocator = allocateX86TargetMachine;
} else if (mod.getEndianness() == Module::BigEndian &&
mod.getPointerSize() == Module::Pointer32) {
TargetMachineAllocator = allocatePowerPCTargetMachine;
} else if (mod.getEndianness() == Module::BigEndian &&
mod.getPointerSize() == Module::Pointer64) {
TargetMachineAllocator = allocateSparcV9TargetMachine;
} else {
// If the module is target independent, favor a target which matches the
// current build system.
#if defined(i386) || defined(__i386__) || defined(__x86__)
TargetMachineAllocator = allocateX86TargetMachine;
#elif defined(sparc) || defined(__sparc__) || defined(__sparcv9)
TargetMachineAllocator = allocateSparcV9TargetMachine;
#elif defined(__POWERPC__) || defined(__ppc__) || defined(__APPLE__)
TargetMachineAllocator = allocatePowerPCTargetMachine;
#else
std::cerr << argv[0] << ": module does not specify a target to use. "
<< "You must use the -march option. If no native target is "
<< "available, use -march=c to emit C code.\n";
return 1;
#endif
}
break;
}
std::auto_ptr<TargetMachine> target(TargetMachineAllocator(mod, 0));
assert(target.get() && "Could not allocate target machine!");
TargetMachine &Target = *target.get();
const TargetData &TD = Target.getTargetData();
// Build up all of the passes that we want to do to the module...
PassManager Passes;
Passes.add(new TargetData("llc", TD.isLittleEndian(), TD.getPointerSize(),
TD.getPointerAlignment(), TD.getDoubleAlignment()));
// Figure out where we are going to send the output...
std::ostream *Out = 0;
if (OutputFilename != "") {
if (OutputFilename != "-") {
// Specified an output filename?
if (!Force && std::ifstream(OutputFilename.c_str())) {
// If force is not specified, make sure not to overwrite a file!
std::cerr << argv[0] << ": error opening '" << OutputFilename
<< "': file exists!\n"
<< "Use -f command line argument to force output\n";
return 1;
}
Out = new std::ofstream(OutputFilename.c_str());
// Make sure that the Out file gets unlinked from the disk if we get a
// SIGINT
RemoveFileOnSignal(OutputFilename);
} else {
Out = &std::cout;
}
} else {
if (InputFilename == "-") {
OutputFilename = "-";
Out = &std::cout;
} else {
OutputFilename = GetFileNameRoot(InputFilename);
if (Arch != CBackend)
OutputFilename += ".s";
else
OutputFilename += ".cbe.c";
if (!Force && std::ifstream(OutputFilename.c_str())) {
// If force is not specified, make sure not to overwrite a file!
std::cerr << argv[0] << ": error opening '" << OutputFilename
<< "': file exists!\n"
<< "Use -f command line argument to force output\n";
return 1;
}
Out = new std::ofstream(OutputFilename.c_str());
if (!Out->good()) {
std::cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
delete Out;
return 1;
}
// Make sure that the Out file gets unlinked from the disk if we get a
// SIGINT
RemoveFileOnSignal(OutputFilename);
}
}
// Ask the target to add backend passes as necessary
if (Target.addPassesToEmitAssembly(Passes, *Out)) {
std::cerr << argv[0] << ": target '" << Target.getName()
<< "' does not support static compilation!\n";
if (Out != &std::cout) delete Out;
// And the Out file is empty and useless, so remove it now.
std::remove(OutputFilename.c_str());
return 1;
} else {
// Run our queue of passes all at once now, efficiently.
Passes.run(*M.get());
}
// Delete the ostream if it's not a stdout stream
if (Out != &std::cout) delete Out;
return 0;
}
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