1 //===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This is the llc code generator driver. It provides a convenient
11 // command-line interface for generating native assembly-language code
12 // or C code, given LLVM bitcode.
14 //===----------------------------------------------------------------------===//
16 #include "llvm/Bitcode/ReaderWriter.h"
17 #include "llvm/CodeGen/FileWriters.h"
18 #include "llvm/CodeGen/LinkAllCodegenComponents.h"
19 #include "llvm/CodeGen/LinkAllAsmWriterComponents.h"
20 #include "llvm/CodeGen/ObjectCodeEmitter.h"
21 #include "llvm/Target/SubtargetFeature.h"
22 #include "llvm/Target/TargetData.h"
23 #include "llvm/Target/TargetMachine.h"
24 #include "llvm/Target/TargetRegistry.h"
25 #include "llvm/Transforms/Scalar.h"
26 #include "llvm/LLVMContext.h"
27 #include "llvm/Module.h"
28 #include "llvm/ModuleProvider.h"
29 #include "llvm/PassManager.h"
30 #include "llvm/Pass.h"
31 #include "llvm/Support/CommandLine.h"
32 #include "llvm/Support/FileUtilities.h"
33 #include "llvm/Support/FormattedStream.h"
34 #include "llvm/Support/ManagedStatic.h"
35 #include "llvm/Support/MemoryBuffer.h"
36 #include "llvm/Support/PluginLoader.h"
37 #include "llvm/Support/PrettyStackTrace.h"
38 #include "llvm/Analysis/Verifier.h"
39 #include "llvm/System/Signals.h"
40 #include "llvm/Config/config.h"
41 #include "llvm/LinkAllVMCore.h"
42 #include "llvm/Target/TargetSelect.h"
46 // General options for llc. Other pass-specific options are specified
47 // within the corresponding llc passes, and target-specific options
48 // and back-end code generation options are specified with the target machine.
50 static cl::opt<std::string>
51 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
53 static cl::opt<std::string>
54 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
56 static cl::opt<bool> Force("f", cl::desc("Overwrite output files"));
58 // Determine optimization level.
61 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
67 static cl::opt<std::string>
68 TargetTriple("mtriple", cl::desc("Override target triple for module"));
70 static cl::opt<std::string>
71 MArch("march", cl::desc("Architecture to generate code for (see --version)"));
73 static cl::opt<std::string>
75 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
76 cl::value_desc("cpu-name"),
79 static cl::list<std::string>
82 cl::desc("Target specific attributes (-mattr=help for details)"),
83 cl::value_desc("a1,+a2,-a3,..."));
85 cl::opt<TargetMachine::CodeGenFileType>
86 FileType("filetype", cl::init(TargetMachine::AssemblyFile),
87 cl::desc("Choose a file type (not all types are supported by all targets):"),
89 clEnumValN(TargetMachine::AssemblyFile, "asm",
90 "Emit an assembly ('.s') file"),
91 clEnumValN(TargetMachine::ObjectFile, "obj",
92 "Emit a native object ('.o') file [experimental]"),
93 clEnumValN(TargetMachine::DynamicLibrary, "dynlib",
94 "Emit a native dynamic library ('.so') file"
98 cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
99 cl::desc("Do not verify input module"));
103 DisableRedZone("disable-red-zone",
104 cl::desc("Do not emit code that uses the red zone."),
108 NoImplicitFloats("no-implicit-float",
109 cl::desc("Don't generate implicit floating point instructions (x86-only)"),
112 // GetFileNameRoot - Helper function to get the basename of a filename.
113 static inline std::string
114 GetFileNameRoot(const std::string &InputFilename) {
115 std::string IFN = InputFilename;
116 std::string outputFilename;
117 int Len = IFN.length();
119 IFN[Len-3] == '.' && IFN[Len-2] == 'b' && IFN[Len-1] == 'c') {
120 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
122 outputFilename = IFN;
124 return outputFilename;
127 static formatted_raw_ostream *GetOutputStream(const char *TargetName,
128 const char *ProgName) {
129 if (OutputFilename != "") {
130 if (OutputFilename == "-")
133 // Make sure that the Out file gets unlinked from the disk if we get a
135 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
138 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(),
139 /*Binary=*/true, Force, error);
140 if (!error.empty()) {
141 errs() << error << '\n';
143 errs() << "Use -f command line argument to force output\n";
147 formatted_raw_ostream *Out =
148 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
153 if (InputFilename == "-") {
154 OutputFilename = "-";
158 OutputFilename = GetFileNameRoot(InputFilename);
162 case TargetMachine::AssemblyFile:
163 if (TargetName[0] == 'c') {
164 if (TargetName[1] == 0)
165 OutputFilename += ".cbe.c";
166 else if (TargetName[1] == 'p' && TargetName[2] == 'p')
167 OutputFilename += ".cpp";
169 OutputFilename += ".s";
171 OutputFilename += ".s";
173 case TargetMachine::ObjectFile:
174 OutputFilename += ".o";
177 case TargetMachine::DynamicLibrary:
178 OutputFilename += LTDL_SHLIB_EXT;
183 // Make sure that the Out file gets unlinked from the disk if we get a
185 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
188 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(),
189 Binary, Force, error);
190 if (!error.empty()) {
191 errs() << error << '\n';
193 errs() << "Use -f command line argument to force output\n";
198 formatted_raw_ostream *Out =
199 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
204 // main - Entry point for the llc compiler.
206 int main(int argc, char **argv) {
207 sys::PrintStackTraceOnErrorSignal();
208 PrettyStackTraceProgram X(argc, argv);
209 LLVMContext &Context = getGlobalContext();
210 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
212 // Initialize targets first.
213 InitializeAllTargets();
214 InitializeAllAsmPrinters();
216 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
218 // Load the module to be compiled...
219 std::string ErrorMessage;
220 std::auto_ptr<Module> M;
222 std::auto_ptr<MemoryBuffer> Buffer(
223 MemoryBuffer::getFileOrSTDIN(InputFilename, &ErrorMessage));
225 M.reset(ParseBitcodeFile(Buffer.get(), Context, &ErrorMessage));
227 errs() << argv[0] << ": bitcode didn't read correctly.\n";
228 errs() << "Reason: " << ErrorMessage << "\n";
231 Module &mod = *M.get();
233 // If we are supposed to override the target triple, do so now.
234 if (!TargetTriple.empty())
235 mod.setTargetTriple(TargetTriple);
237 // Allocate target machine. First, check whether the user has
238 // explicitly specified an architecture to compile for.
239 const Target *TheTarget = 0;
240 if (!MArch.empty()) {
241 for (TargetRegistry::iterator it = TargetRegistry::begin(),
242 ie = TargetRegistry::end(); it != ie; ++it) {
243 if (MArch == it->getName()) {
250 errs() << argv[0] << ": error: invalid target '" << MArch << "'.\n";
255 TheTarget = TargetRegistry::lookupTarget(mod.getTargetTriple(),
256 /*FallbackToHost=*/true,
257 /*RequireJIT=*/false,
259 if (TheTarget == 0) {
260 errs() << argv[0] << ": error auto-selecting target for module '"
261 << Err << "'. Please use the -march option to explicitly "
262 << "pick a target.\n";
267 // Package up features to be passed to target/subtarget
268 std::string FeaturesStr;
269 if (MCPU.size() || MAttrs.size()) {
270 SubtargetFeatures Features;
271 Features.setCPU(MCPU);
272 for (unsigned i = 0; i != MAttrs.size(); ++i)
273 Features.AddFeature(MAttrs[i]);
274 FeaturesStr = Features.getString();
277 std::auto_ptr<TargetMachine>
278 target(TheTarget->createTargetMachine(mod, FeaturesStr));
279 assert(target.get() && "Could not allocate target machine!");
280 TargetMachine &Target = *target.get();
282 // Figure out where we are going to send the output...
283 formatted_raw_ostream *Out = GetOutputStream(TheTarget->getName(), argv[0]);
284 if (Out == 0) return 1;
286 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
289 errs() << argv[0] << ": invalid optimization level.\n";
292 case '0': OLvl = CodeGenOpt::None; break;
294 case '2': OLvl = CodeGenOpt::Default; break;
295 case '3': OLvl = CodeGenOpt::Aggressive; break;
298 // If this target requires addPassesToEmitWholeFile, do it now. This is
299 // used by strange things like the C backend.
300 if (Target.WantsWholeFile()) {
302 PM.add(new TargetData(*Target.getTargetData()));
304 PM.add(createVerifierPass());
306 // Ask the target to add backend passes as necessary.
307 if (Target.addPassesToEmitWholeFile(PM, *Out, FileType, OLvl)) {
308 errs() << argv[0] << ": target does not support generation of this"
310 if (Out != &fouts()) delete Out;
311 // And the Out file is empty and useless, so remove it now.
312 sys::Path(OutputFilename).eraseFromDisk();
317 // Build up all of the passes that we want to do to the module.
318 ExistingModuleProvider Provider(M.release());
319 FunctionPassManager Passes(&Provider);
320 Passes.add(new TargetData(*Target.getTargetData()));
324 Passes.add(createVerifierPass());
327 // Ask the target to add backend passes as necessary.
328 ObjectCodeEmitter *OCE = 0;
330 // Override default to generate verbose assembly.
331 Target.setAsmVerbosityDefault(true);
333 switch (Target.addPassesToEmitFile(Passes, *Out, FileType, OLvl)) {
335 assert(0 && "Invalid file model!");
337 case FileModel::Error:
338 errs() << argv[0] << ": target does not support generation of this"
340 if (Out != &fouts()) delete Out;
341 // And the Out file is empty and useless, so remove it now.
342 sys::Path(OutputFilename).eraseFromDisk();
344 case FileModel::AsmFile:
346 case FileModel::MachOFile:
347 OCE = AddMachOWriter(Passes, *Out, Target);
349 case FileModel::ElfFile:
350 OCE = AddELFWriter(Passes, *Out, Target);
354 if (Target.addPassesToEmitFileFinish(Passes, OCE, OLvl)) {
355 errs() << argv[0] << ": target does not support generation of this"
357 if (Out != &fouts()) delete Out;
358 // And the Out file is empty and useless, so remove it now.
359 sys::Path(OutputFilename).eraseFromDisk();
363 Passes.doInitialization();
365 // Run our queue of passes all at once now, efficiently.
366 // TODO: this could lazily stream functions out of the module.
367 for (Module::iterator I = mod.begin(), E = mod.end(); I != E; ++I)
368 if (!I->isDeclaration()) {
370 I->addFnAttr(Attribute::NoRedZone);
371 if (NoImplicitFloats)
372 I->addFnAttr(Attribute::NoImplicitFloat);
376 Passes.doFinalization();
381 // Delete the ostream if it's not a stdout stream
382 if (Out != &fouts()) delete Out;