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/Target/SubtargetFeature.h"
21 #include "llvm/Target/TargetData.h"
22 #include "llvm/Target/TargetMachine.h"
23 #include "llvm/Target/TargetMachineRegistry.h"
24 #include "llvm/Transforms/Scalar.h"
25 #include "llvm/Module.h"
26 #include "llvm/ModuleProvider.h"
27 #include "llvm/PassManager.h"
28 #include "llvm/Pass.h"
29 #include "llvm/Support/CommandLine.h"
30 #include "llvm/Support/FileUtilities.h"
31 #include "llvm/Support/ManagedStatic.h"
32 #include "llvm/Support/MemoryBuffer.h"
33 #include "llvm/Support/PluginLoader.h"
34 #include "llvm/Support/PrettyStackTrace.h"
35 #include "llvm/Support/RegistryParser.h"
36 #include "llvm/Support/raw_ostream.h"
37 #include "llvm/Analysis/Verifier.h"
38 #include "llvm/System/Signals.h"
39 #include "llvm/Config/config.h"
40 #include "llvm/LinkAllVMCore.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 static cl::opt<bool> Fast("fast",
59 cl::desc("Generate code quickly, potentially sacrificing code quality"));
61 static cl::opt<std::string>
62 TargetTriple("mtriple", cl::desc("Override target triple for module"));
64 static cl::opt<const TargetMachineRegistry::entry*, false,
65 RegistryParser<TargetMachine> >
66 MArch("march", cl::desc("Architecture to generate code for:"));
68 static cl::opt<std::string>
70 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
71 cl::value_desc("cpu-name"),
74 static cl::list<std::string>
77 cl::desc("Target specific attributes (-mattr=help for details)"),
78 cl::value_desc("a1,+a2,-a3,..."));
80 cl::opt<TargetMachine::CodeGenFileType>
81 FileType("filetype", cl::init(TargetMachine::AssemblyFile),
82 cl::desc("Choose a file type (not all types are supported by all targets):"),
84 clEnumValN(TargetMachine::AssemblyFile, "asm",
85 "Emit an assembly ('.s') file"),
86 clEnumValN(TargetMachine::ObjectFile, "obj",
87 "Emit a native object ('.o') file [experimental]"),
88 clEnumValN(TargetMachine::DynamicLibrary, "dynlib",
89 "Emit a native dynamic library ('.so') file"
93 cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
94 cl::desc("Do not verify input module"));
97 // GetFileNameRoot - Helper function to get the basename of a filename.
98 static inline std::string
99 GetFileNameRoot(const std::string &InputFilename) {
100 std::string IFN = InputFilename;
101 std::string outputFilename;
102 int Len = IFN.length();
104 IFN[Len-3] == '.' && IFN[Len-2] == 'b' && IFN[Len-1] == 'c') {
105 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
107 outputFilename = IFN;
109 return outputFilename;
112 static raw_ostream *GetOutputStream(const char *ProgName) {
113 if (OutputFilename != "") {
114 if (OutputFilename == "-")
117 // Specified an output filename?
118 if (!Force && std::ifstream(OutputFilename.c_str())) {
119 // If force is not specified, make sure not to overwrite a file!
120 std::cerr << ProgName << ": error opening '" << OutputFilename
121 << "': file exists!\n"
122 << "Use -f command line argument to force output\n";
125 // Make sure that the Out file gets unlinked from the disk if we get a
127 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
130 raw_ostream *Out = new raw_fd_ostream(OutputFilename.c_str(), true, error);
131 if (!error.empty()) {
132 std::cerr << error << '\n';
140 if (InputFilename == "-") {
141 OutputFilename = "-";
145 OutputFilename = GetFileNameRoot(InputFilename);
149 case TargetMachine::AssemblyFile:
150 if (MArch->Name[0] == 'c') {
151 if (MArch->Name[1] == 0)
152 OutputFilename += ".cbe.c";
153 else if (MArch->Name[1] == 'p' && MArch->Name[2] == 'p')
154 OutputFilename += ".cpp";
156 OutputFilename += ".s";
158 OutputFilename += ".s";
160 case TargetMachine::ObjectFile:
161 OutputFilename += ".o";
164 case TargetMachine::DynamicLibrary:
165 OutputFilename += LTDL_SHLIB_EXT;
170 if (!Force && std::ifstream(OutputFilename.c_str())) {
171 // If force is not specified, make sure not to overwrite a file!
172 std::cerr << ProgName << ": error opening '" << OutputFilename
173 << "': file exists!\n"
174 << "Use -f command line argument to force output\n";
178 // Make sure that the Out file gets unlinked from the disk if we get a
180 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
183 raw_ostream *Out = new raw_fd_ostream(OutputFilename.c_str(), Binary, error);
184 if (!error.empty()) {
185 std::cerr << error << '\n';
193 // main - Entry point for the llc compiler.
195 int main(int argc, char **argv) {
196 sys::PrintStackTraceOnErrorSignal();
197 PrettyStackTraceProgram X(argc, argv);
198 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
199 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
201 // Load the module to be compiled...
202 std::string ErrorMessage;
203 std::auto_ptr<Module> M;
205 std::auto_ptr<MemoryBuffer> Buffer(
206 MemoryBuffer::getFileOrSTDIN(InputFilename, &ErrorMessage));
208 M.reset(ParseBitcodeFile(Buffer.get(), &ErrorMessage));
210 std::cerr << argv[0] << ": bitcode didn't read correctly.\n";
211 std::cerr << "Reason: " << ErrorMessage << "\n";
214 Module &mod = *M.get();
216 // If we are supposed to override the target triple, do so now.
217 if (!TargetTriple.empty())
218 mod.setTargetTriple(TargetTriple);
220 // Allocate target machine. First, check whether the user has
221 // explicitly specified an architecture to compile for.
224 MArch = TargetMachineRegistry::getClosestStaticTargetForModule(mod, Err);
226 std::cerr << argv[0] << ": error auto-selecting target for module '"
227 << Err << "'. Please use the -march option to explicitly "
228 << "pick a target.\n";
233 // Package up features to be passed to target/subtarget
234 std::string FeaturesStr;
235 if (MCPU.size() || MAttrs.size()) {
236 SubtargetFeatures Features;
237 Features.setCPU(MCPU);
238 for (unsigned i = 0; i != MAttrs.size(); ++i)
239 Features.AddFeature(MAttrs[i]);
240 FeaturesStr = Features.getString();
243 std::auto_ptr<TargetMachine> target(MArch->CtorFn(mod, FeaturesStr));
244 assert(target.get() && "Could not allocate target machine!");
245 TargetMachine &Target = *target.get();
247 // Figure out where we are going to send the output...
248 raw_ostream *Out = GetOutputStream(argv[0]);
249 if (Out == 0) return 1;
251 // If this target requires addPassesToEmitWholeFile, do it now. This is
252 // used by strange things like the C backend.
253 if (Target.WantsWholeFile()) {
255 PM.add(new TargetData(*Target.getTargetData()));
257 PM.add(createVerifierPass());
259 // Ask the target to add backend passes as necessary.
260 if (Target.addPassesToEmitWholeFile(PM, *Out, FileType, Fast)) {
261 std::cerr << argv[0] << ": target does not support generation of this"
263 if (Out != &outs()) delete Out;
264 // And the Out file is empty and useless, so remove it now.
265 sys::Path(OutputFilename).eraseFromDisk();
270 // Build up all of the passes that we want to do to the module.
271 ExistingModuleProvider Provider(M.release());
272 FunctionPassManager Passes(&Provider);
273 Passes.add(new TargetData(*Target.getTargetData()));
277 Passes.add(createVerifierPass());
280 // Ask the target to add backend passes as necessary.
281 MachineCodeEmitter *MCE = 0;
283 // Override default to generate verbose assembly.
284 Target.setAsmVerbosityDefault(true);
286 switch (Target.addPassesToEmitFile(Passes, *Out, FileType, Fast)) {
288 assert(0 && "Invalid file model!");
290 case FileModel::Error:
291 std::cerr << argv[0] << ": target does not support generation of this"
293 if (Out != &outs()) delete Out;
294 // And the Out file is empty and useless, so remove it now.
295 sys::Path(OutputFilename).eraseFromDisk();
297 case FileModel::AsmFile:
299 case FileModel::MachOFile:
300 MCE = AddMachOWriter(Passes, *Out, Target);
302 case FileModel::ElfFile:
303 MCE = AddELFWriter(Passes, *Out, Target);
307 if (Target.addPassesToEmitFileFinish(Passes, MCE, Fast)) {
308 std::cerr << argv[0] << ": target does not support generation of this"
310 if (Out != &outs()) delete Out;
311 // And the Out file is empty and useless, so remove it now.
312 sys::Path(OutputFilename).eraseFromDisk();
316 Passes.doInitialization();
318 // Run our queue of passes all at once now, efficiently.
319 // TODO: this could lazily stream functions out of the module.
320 for (Module::iterator I = mod.begin(), E = mod.end(); I != E; ++I)
321 if (!I->isDeclaration())
324 Passes.doFinalization();
327 // Delete the ostream if it's not a stdout stream
328 if (Out != &outs()) delete Out;