1 //===- opt.cpp - The LLVM Modular Optimizer -------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Optimizations may be specified an arbitrary number of times on the command
11 // line, They are run in the order specified.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/Module.h"
16 #include "llvm/PassManager.h"
17 #include "llvm/Bitcode/ReaderWriter.h"
18 #include "llvm/Assembly/PrintModulePass.h"
19 #include "llvm/Analysis/Verifier.h"
20 #include "llvm/Analysis/LoopPass.h"
21 #include "llvm/Target/TargetData.h"
22 #include "llvm/Target/TargetMachine.h"
23 #include "llvm/Support/PassNameParser.h"
24 #include "llvm/System/Signals.h"
25 #include "llvm/Support/ManagedStatic.h"
26 #include "llvm/Support/MemoryBuffer.h"
27 #include "llvm/Support/PluginLoader.h"
28 #include "llvm/Support/Streams.h"
29 #include "llvm/Support/SystemUtils.h"
30 #include "llvm/LinkAllPasses.h"
31 #include "llvm/LinkAllVMCore.h"
38 // The OptimizationList is automatically populated with registered Passes by the
41 static cl::list<const PassInfo*, bool, PassNameParser>
42 PassList(cl::desc("Optimizations available:"));
44 // Other command line options...
46 static cl::opt<std::string>
47 InputFilename(cl::Positional, cl::desc("<input bytecode file>"),
48 cl::init("-"), cl::value_desc("filename"));
50 static cl::opt<std::string>
51 OutputFilename("o", cl::desc("Override output filename"),
52 cl::value_desc("filename"), cl::init("-"));
55 Force("f", cl::desc("Overwrite output files"));
58 PrintEachXForm("p", cl::desc("Print module after each transformation"));
61 NoOutput("disable-output",
62 cl::desc("Do not write result bytecode file"), cl::Hidden);
65 NoVerify("disable-verify", cl::desc("Do not verify result module"), cl::Hidden);
68 VerifyEach("verify-each", cl::desc("Verify after each transform"));
71 StripDebug("strip-debug",
72 cl::desc("Strip debugger symbol info from translation unit"));
75 DisableInline("disable-inlining", cl::desc("Do not run the inliner pass"));
78 DisableOptimizations("disable-opt",
79 cl::desc("Do not run any optimization passes"));
82 StandardCompileOpts("std-compile-opts",
83 cl::desc("Include the standard compile time optimizations"));
86 Quiet("q", cl::desc("Obsolete option"), cl::Hidden);
89 QuietA("quiet", cl::desc("Alias for -q"), cl::aliasopt(Quiet));
92 AnalyzeOnly("analyze", cl::desc("Only perform analysis, no optimization"));
94 // ---------- Define Printers for module and function passes ------------
97 struct ModulePassPrinter : public ModulePass {
99 const PassInfo *PassToPrint;
100 ModulePassPrinter(const PassInfo *PI) : ModulePass((intptr_t)&ID),
103 virtual bool runOnModule(Module &M) {
105 cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
106 getAnalysisID<Pass>(PassToPrint).print(cout, &M);
109 // Get and print pass...
113 virtual const char *getPassName() const { return "'Pass' Printer"; }
115 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
116 AU.addRequiredID(PassToPrint);
117 AU.setPreservesAll();
121 char ModulePassPrinter::ID = 0;
122 struct FunctionPassPrinter : public FunctionPass {
123 const PassInfo *PassToPrint;
125 FunctionPassPrinter(const PassInfo *PI) : FunctionPass((intptr_t)&ID),
128 virtual bool runOnFunction(Function &F) {
130 cout << "Printing analysis '" << PassToPrint->getPassName()
131 << "' for function '" << F.getName() << "':\n";
133 // Get and print pass...
134 getAnalysisID<Pass>(PassToPrint).print(cout, F.getParent());
138 virtual const char *getPassName() const { return "FunctionPass Printer"; }
140 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
141 AU.addRequiredID(PassToPrint);
142 AU.setPreservesAll();
146 char FunctionPassPrinter::ID = 0;
147 struct BasicBlockPassPrinter : public BasicBlockPass {
148 const PassInfo *PassToPrint;
150 BasicBlockPassPrinter(const PassInfo *PI)
151 : BasicBlockPass((intptr_t)&ID), PassToPrint(PI) {}
153 virtual bool runOnBasicBlock(BasicBlock &BB) {
155 cout << "Printing Analysis info for BasicBlock '" << BB.getName()
156 << "': Pass " << PassToPrint->getPassName() << ":\n";
159 // Get and print pass...
160 getAnalysisID<Pass>(PassToPrint).print(cout, BB.getParent()->getParent());
164 virtual const char *getPassName() const { return "BasicBlockPass Printer"; }
166 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
167 AU.addRequiredID(PassToPrint);
168 AU.setPreservesAll();
172 char BasicBlockPassPrinter::ID = 0;
173 inline void addPass(PassManager &PM, Pass *P) {
174 // Add the pass to the pass manager...
177 // If we are verifying all of the intermediate steps, add the verifier...
178 if (VerifyEach) PM.add(createVerifierPass());
181 void AddStandardCompilePasses(PassManager &PM) {
182 PM.add(createVerifierPass()); // Verify that input is correct
184 addPass(PM, createLowerSetJmpPass()); // Lower llvm.setjmp/.longjmp
186 // If the -strip-debug command line option was specified, do it.
188 addPass(PM, createStripSymbolsPass(true));
190 if (DisableOptimizations) return;
192 addPass(PM, createRaiseAllocationsPass()); // call %malloc -> malloc inst
193 addPass(PM, createCFGSimplificationPass()); // Clean up disgusting code
194 addPass(PM, createPromoteMemoryToRegisterPass());// Kill useless allocas
195 addPass(PM, createGlobalOptimizerPass()); // Optimize out global vars
196 addPass(PM, createGlobalDCEPass()); // Remove unused fns and globs
197 addPass(PM, createIPConstantPropagationPass());// IP Constant Propagation
198 addPass(PM, createDeadArgEliminationPass()); // Dead argument elimination
199 addPass(PM, createInstructionCombiningPass()); // Clean up after IPCP & DAE
200 addPass(PM, createCFGSimplificationPass()); // Clean up after IPCP & DAE
202 addPass(PM, createPruneEHPass()); // Remove dead EH info
205 addPass(PM, createFunctionInliningPass()); // Inline small functions
206 addPass(PM, createArgumentPromotionPass()); // Scalarize uninlined fn args
208 addPass(PM, createTailDuplicationPass()); // Simplify cfg by copying code
209 addPass(PM, createInstructionCombiningPass()); // Cleanup for scalarrepl.
210 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
211 addPass(PM, createScalarReplAggregatesPass()); // Break up aggregate allocas
212 addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
213 addPass(PM, createCondPropagationPass()); // Propagate conditionals
215 addPass(PM, createTailCallEliminationPass()); // Eliminate tail calls
216 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
217 addPass(PM, createReassociatePass()); // Reassociate expressions
218 addPass(PM, createLoopRotatePass());
219 addPass(PM, createLICMPass()); // Hoist loop invariants
220 addPass(PM, createLoopUnswitchPass()); // Unswitch loops.
221 addPass(PM, createInstructionCombiningPass()); // Clean up after LICM/reassoc
222 addPass(PM, createIndVarSimplifyPass()); // Canonicalize indvars
223 addPass(PM, createLoopUnrollPass()); // Unroll small loops
224 addPass(PM, createInstructionCombiningPass()); // Clean up after the unroller
225 addPass(PM, createLoadValueNumberingPass()); // GVN for load instructions
226 addPass(PM, createGCSEPass()); // Remove common subexprs
227 addPass(PM, createSCCPPass()); // Constant prop with SCCP
229 // Run instcombine after redundancy elimination to exploit opportunities
230 // opened up by them.
231 addPass(PM, createInstructionCombiningPass());
232 addPass(PM, createCondPropagationPass()); // Propagate conditionals
234 addPass(PM, createDeadStoreEliminationPass()); // Delete dead stores
235 addPass(PM, createAggressiveDCEPass()); // SSA based 'Aggressive DCE'
236 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
237 addPass(PM, createSimplifyLibCallsPass()); // Library Call Optimizations
238 addPass(PM, createDeadTypeEliminationPass()); // Eliminate dead types
239 addPass(PM, createConstantMergePass()); // Merge dup global constants
242 } // anonymous namespace
245 //===----------------------------------------------------------------------===//
248 int main(int argc, char **argv) {
249 llvm_shutdown_obj X; // Call llvm_shutdown() on exit.
251 cl::ParseCommandLineOptions(argc, argv,
252 " llvm .bc -> .bc modular optimizer and analysis printer \n");
253 sys::PrintStackTraceOnErrorSignal();
255 // Allocate a full target machine description only if necessary.
256 // FIXME: The choice of target should be controllable on the command line.
257 std::auto_ptr<TargetMachine> target;
259 std::string ErrorMessage;
261 // Load the input module...
262 std::auto_ptr<Module> M;
264 = MemoryBuffer::getFileOrSTDIN(&InputFilename[0], InputFilename.size());
267 ErrorMessage = "Error reading file '" + InputFilename + "'";
269 M.reset(ParseBitcodeFile(Buffer, &ErrorMessage));
273 cerr << argv[0] << ": ";
274 if (ErrorMessage.size())
275 cerr << ErrorMessage << "\n";
277 cerr << "bytecode didn't read correctly.\n";
281 // Figure out what stream we are supposed to write to...
282 // FIXME: cout is not binary!
283 std::ostream *Out = &std::cout; // Default to printing to stdout...
284 if (OutputFilename != "-") {
285 if (!Force && std::ifstream(OutputFilename.c_str())) {
286 // If force is not specified, make sure not to overwrite a file!
287 cerr << argv[0] << ": error opening '" << OutputFilename
288 << "': file exists!\n"
289 << "Use -f command line argument to force output\n";
292 std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
294 Out = new std::ofstream(OutputFilename.c_str(), io_mode);
297 cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
301 // Make sure that the Output file gets unlinked from the disk if we get a
303 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
306 // If the output is set to be emitted to standard out, and standard out is a
307 // console, print out a warning message and refuse to do it. We don't
308 // impress anyone by spewing tons of binary goo to a terminal.
309 if (!Force && !NoOutput && CheckBytecodeOutputToConsole(Out,!Quiet)) {
313 // Create a PassManager to hold and optimize the collection of passes we are
318 // Add an appropriate TargetData instance for this module...
319 Passes.add(new TargetData(M.get()));
321 // If -std-compile-opts is given, add in all the standard compilation
322 // optimizations first. This will handle -strip-debug, -disable-inline,
323 // and -disable-opt as well.
324 if (StandardCompileOpts)
325 AddStandardCompilePasses(Passes);
327 // otherwise if the -strip-debug command line option was specified, add it.
329 addPass(Passes, createStripSymbolsPass(true));
331 // Create a new optimization pass for each one specified on the command line
332 for (unsigned i = 0; i < PassList.size(); ++i) {
333 const PassInfo *PassInf = PassList[i];
335 if (PassInf->getNormalCtor())
336 P = PassInf->getNormalCtor()();
338 cerr << argv[0] << ": cannot create pass: "
339 << PassInf->getPassName() << "\n";
344 if (dynamic_cast<BasicBlockPass*>(P))
345 Passes.add(new BasicBlockPassPrinter(PassInf));
346 else if (dynamic_cast<FunctionPass*>(P))
347 Passes.add(new FunctionPassPrinter(PassInf));
349 Passes.add(new ModulePassPrinter(PassInf));
354 Passes.add(new PrintModulePass(&cerr));
357 // Check that the module is well formed on completion of optimization
358 if (!NoVerify && !VerifyEach)
359 Passes.add(createVerifierPass());
361 // Write bytecode out to disk or cout as the last step...
362 if (!NoOutput && !AnalyzeOnly)
363 Passes.add(CreateBitcodeWriterPass(*Out));
365 // Now that we have all of the passes ready, run them.
366 Passes.run(*M.get());
370 } catch (const std::string& msg) {
371 cerr << argv[0] << ": " << msg << "\n";
373 cerr << argv[0] << ": Unexpected unknown exception occurred.\n";