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/TargetMachineRegistry.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/Support/RegistryParser.h"
39 #include "llvm/Analysis/Verifier.h"
40 #include "llvm/System/Signals.h"
41 #include "llvm/Config/config.h"
42 #include "llvm/LinkAllVMCore.h"
43 #include "llvm/Target/TargetSelect.h"
47 // General options for llc. Other pass-specific options are specified
48 // within the corresponding llc passes, and target-specific options
49 // and back-end code generation options are specified with the target machine.
51 static cl::opt<std::string>
52 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
54 static cl::opt<std::string>
55 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
57 static cl::opt<bool> Force("f", cl::desc("Overwrite output files"));
59 // Determine optimization level.
62 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
68 static cl::opt<std::string>
69 TargetTriple("mtriple", cl::desc("Override target triple for module"));
71 static cl::opt<const TargetMachineRegistry::entry*, false,
72 RegistryParser<TargetMachine> >
73 MArch("march", cl::desc("Architecture to generate code for:"));
75 static cl::opt<std::string>
77 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
78 cl::value_desc("cpu-name"),
81 static cl::list<std::string>
84 cl::desc("Target specific attributes (-mattr=help for details)"),
85 cl::value_desc("a1,+a2,-a3,..."));
87 cl::opt<TargetMachine::CodeGenFileType>
88 FileType("filetype", cl::init(TargetMachine::AssemblyFile),
89 cl::desc("Choose a file type (not all types are supported by all targets):"),
91 clEnumValN(TargetMachine::AssemblyFile, "asm",
92 "Emit an assembly ('.s') file"),
93 clEnumValN(TargetMachine::ObjectFile, "obj",
94 "Emit a native object ('.o') file [experimental]"),
95 clEnumValN(TargetMachine::DynamicLibrary, "dynlib",
96 "Emit a native dynamic library ('.so') file"
100 cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
101 cl::desc("Do not verify input module"));
105 DisableRedZone("disable-red-zone",
106 cl::desc("Do not emit code that uses the red zone."),
110 NoImplicitFloats("no-implicit-float",
111 cl::desc("Don't generate implicit floating point instructions (x86-only)"),
114 // GetFileNameRoot - Helper function to get the basename of a filename.
115 static inline std::string
116 GetFileNameRoot(const std::string &InputFilename) {
117 std::string IFN = InputFilename;
118 std::string outputFilename;
119 int Len = IFN.length();
121 IFN[Len-3] == '.' && IFN[Len-2] == 'b' && IFN[Len-1] == 'c') {
122 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
124 outputFilename = IFN;
126 return outputFilename;
129 static formatted_raw_ostream *GetOutputStream(const char *TargetName,
130 const char *ProgName) {
131 if (OutputFilename != "") {
132 if (OutputFilename == "-")
135 // Make sure that the Out file gets unlinked from the disk if we get a
137 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
140 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(),
141 /*Binary=*/true, Force, error);
142 if (!error.empty()) {
143 errs() << error << '\n';
145 errs() << "Use -f command line argument to force output\n";
149 formatted_raw_ostream *Out =
150 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
155 if (InputFilename == "-") {
156 OutputFilename = "-";
160 OutputFilename = GetFileNameRoot(InputFilename);
164 case TargetMachine::AssemblyFile:
165 if (TargetName[0] == 'c') {
166 if (TargetName[1] == 0)
167 OutputFilename += ".cbe.c";
168 else if (TargetName[1] == 'p' && TargetName[2] == 'p')
169 OutputFilename += ".cpp";
171 OutputFilename += ".s";
173 OutputFilename += ".s";
175 case TargetMachine::ObjectFile:
176 OutputFilename += ".o";
179 case TargetMachine::DynamicLibrary:
180 OutputFilename += LTDL_SHLIB_EXT;
185 // Make sure that the Out file gets unlinked from the disk if we get a
187 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
190 raw_fd_ostream *FDOut = new raw_fd_ostream(OutputFilename.c_str(),
191 Binary, Force, error);
192 if (!error.empty()) {
193 errs() << error << '\n';
195 errs() << "Use -f command line argument to force output\n";
200 formatted_raw_ostream *Out =
201 new formatted_raw_ostream(*FDOut, formatted_raw_ostream::DELETE_STREAM);
206 // main - Entry point for the llc compiler.
208 int main(int argc, char **argv) {
209 sys::PrintStackTraceOnErrorSignal();
210 PrettyStackTraceProgram X(argc, argv);
211 LLVMContext &Context = getGlobalContext();
212 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
213 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
215 InitializeAllTargets();
216 InitializeAllAsmPrinters();
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;
241 TheTarget = &MArch->TheTarget;
244 TheTarget = TargetRegistry::getClosestStaticTargetForModule(mod, Err);
245 if (TheTarget == 0) {
246 errs() << argv[0] << ": error auto-selecting target for module '"
247 << Err << "'. Please use the -march option to explicitly "
248 << "pick a target.\n";
253 // Package up features to be passed to target/subtarget
254 std::string FeaturesStr;
255 if (MCPU.size() || MAttrs.size()) {
256 SubtargetFeatures Features;
257 Features.setCPU(MCPU);
258 for (unsigned i = 0; i != MAttrs.size(); ++i)
259 Features.AddFeature(MAttrs[i]);
260 FeaturesStr = Features.getString();
263 std::auto_ptr<TargetMachine>
264 target(TheTarget->createTargetMachine(mod, FeaturesStr));
265 assert(target.get() && "Could not allocate target machine!");
266 TargetMachine &Target = *target.get();
268 // Figure out where we are going to send the output...
269 formatted_raw_ostream *Out = GetOutputStream(TheTarget->getName(), argv[0]);
270 if (Out == 0) return 1;
272 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
275 errs() << argv[0] << ": invalid optimization level.\n";
278 case '0': OLvl = CodeGenOpt::None; break;
280 case '2': OLvl = CodeGenOpt::Default; break;
281 case '3': OLvl = CodeGenOpt::Aggressive; break;
284 // If this target requires addPassesToEmitWholeFile, do it now. This is
285 // used by strange things like the C backend.
286 if (Target.WantsWholeFile()) {
288 PM.add(new TargetData(*Target.getTargetData()));
290 PM.add(createVerifierPass());
292 // Ask the target to add backend passes as necessary.
293 if (Target.addPassesToEmitWholeFile(PM, *Out, FileType, OLvl)) {
294 errs() << argv[0] << ": target does not support generation of this"
296 if (Out != &fouts()) delete Out;
297 // And the Out file is empty and useless, so remove it now.
298 sys::Path(OutputFilename).eraseFromDisk();
303 // Build up all of the passes that we want to do to the module.
304 ExistingModuleProvider Provider(M.release());
305 FunctionPassManager Passes(&Provider);
306 Passes.add(new TargetData(*Target.getTargetData()));
310 Passes.add(createVerifierPass());
313 // Ask the target to add backend passes as necessary.
314 ObjectCodeEmitter *OCE = 0;
316 // Override default to generate verbose assembly.
317 Target.setAsmVerbosityDefault(true);
319 switch (Target.addPassesToEmitFile(Passes, *Out, FileType, OLvl)) {
321 assert(0 && "Invalid file model!");
323 case FileModel::Error:
324 errs() << argv[0] << ": target does not support generation of this"
326 if (Out != &fouts()) delete Out;
327 // And the Out file is empty and useless, so remove it now.
328 sys::Path(OutputFilename).eraseFromDisk();
330 case FileModel::AsmFile:
332 case FileModel::MachOFile:
333 OCE = AddMachOWriter(Passes, *Out, Target);
335 case FileModel::ElfFile:
336 OCE = AddELFWriter(Passes, *Out, Target);
340 if (Target.addPassesToEmitFileFinish(Passes, OCE, OLvl)) {
341 errs() << argv[0] << ": target does not support generation of this"
343 if (Out != &fouts()) delete Out;
344 // And the Out file is empty and useless, so remove it now.
345 sys::Path(OutputFilename).eraseFromDisk();
349 Passes.doInitialization();
351 // Run our queue of passes all at once now, efficiently.
352 // TODO: this could lazily stream functions out of the module.
353 for (Module::iterator I = mod.begin(), E = mod.end(); I != E; ++I)
354 if (!I->isDeclaration()) {
356 I->addFnAttr(Attribute::NoRedZone);
357 if (NoImplicitFloats)
358 I->addFnAttr(Attribute::NoImplicitFloat);
362 Passes.doFinalization();
367 // Delete the ostream if it's not a stdout stream
368 if (Out != &fouts()) delete Out;