1 //===- opt.cpp - The LLVM Modular Optimizer -------------------------------===//
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 // 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/ModuleProvider.h"
17 #include "llvm/PassManager.h"
18 #include "llvm/CallGraphSCCPass.h"
19 #include "llvm/Bitcode/ReaderWriter.h"
20 #include "llvm/Assembly/PrintModulePass.h"
21 #include "llvm/Analysis/Verifier.h"
22 #include "llvm/Analysis/LoopPass.h"
23 #include "llvm/Analysis/CallGraph.h"
24 #include "llvm/Target/TargetData.h"
25 #include "llvm/Target/TargetMachine.h"
26 #include "llvm/Support/PassNameParser.h"
27 #include "llvm/System/Signals.h"
28 #include "llvm/Support/ManagedStatic.h"
29 #include "llvm/Support/MemoryBuffer.h"
30 #include "llvm/Support/PluginLoader.h"
31 #include "llvm/Support/Streams.h"
32 #include "llvm/Support/SystemUtils.h"
33 #include "llvm/Support/raw_ostream.h"
34 #include "llvm/LinkAllPasses.h"
35 #include "llvm/LinkAllVMCore.h"
42 // The OptimizationList is automatically populated with registered Passes by the
45 static cl::list<const PassInfo*, bool, PassNameParser>
46 PassList(cl::desc("Optimizations available:"));
48 // Other command line options...
50 static cl::opt<std::string>
51 InputFilename(cl::Positional, cl::desc("<input bitcode file>"),
52 cl::init("-"), cl::value_desc("filename"));
54 static cl::opt<std::string>
55 OutputFilename("o", cl::desc("Override output filename"),
56 cl::value_desc("filename"), cl::init("-"));
59 Force("f", cl::desc("Overwrite output files"));
62 PrintEachXForm("p", cl::desc("Print module after each transformation"));
65 NoOutput("disable-output",
66 cl::desc("Do not write result bitcode file"), cl::Hidden);
69 NoVerify("disable-verify", cl::desc("Do not verify result module"), cl::Hidden);
72 VerifyEach("verify-each", cl::desc("Verify after each transform"));
75 StripDebug("strip-debug",
76 cl::desc("Strip debugger symbol info from translation unit"));
79 DisableInline("disable-inlining", cl::desc("Do not run the inliner pass"));
82 DisableOptimizations("disable-opt",
83 cl::desc("Do not run any optimization passes"));
86 StandardCompileOpts("std-compile-opts",
87 cl::desc("Include the standard compile time optimizations"));
91 cl::desc("Optimization level 1. Similar to llvm-gcc -O1"));
95 cl::desc("Optimization level 2. Similar to llvm-gcc -O2"));
99 cl::desc("Optimization level 3. Similar to llvm-gcc -O3"));
102 UnitAtATime("funit-at-a-time",
103 cl::desc("Enable IPO. This is same as llvm-gcc's -funit-at-a-time"));
106 DisableSimplifyLibCalls("disable-simplify-libcalls",
107 cl::desc("Disable simplify-libcalls"));
110 Quiet("q", cl::desc("Obsolete option"), cl::Hidden);
113 QuietA("quiet", cl::desc("Alias for -q"), cl::aliasopt(Quiet));
116 AnalyzeOnly("analyze", cl::desc("Only perform analysis, no optimization"));
118 // ---------- Define Printers for module and function passes ------------
121 struct CallGraphSCCPassPrinter : public CallGraphSCCPass {
123 const PassInfo *PassToPrint;
124 CallGraphSCCPassPrinter(const PassInfo *PI) :
125 CallGraphSCCPass((intptr_t)&ID), PassToPrint(PI) {}
127 virtual bool runOnSCC(const std::vector<CallGraphNode *>&SCC) {
129 cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
131 for (unsigned i = 0, e = SCC.size(); i != e; ++i) {
132 Function *F = SCC[i]->getFunction();
134 getAnalysisID<Pass>(PassToPrint).print(cout, F->getParent());
137 // Get and print pass...
141 virtual const char *getPassName() const { return "'Pass' Printer"; }
143 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
144 AU.addRequiredID(PassToPrint);
145 AU.setPreservesAll();
149 char CallGraphSCCPassPrinter::ID = 0;
151 struct ModulePassPrinter : public ModulePass {
153 const PassInfo *PassToPrint;
154 ModulePassPrinter(const PassInfo *PI) : ModulePass((intptr_t)&ID),
157 virtual bool runOnModule(Module &M) {
159 cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
160 getAnalysisID<Pass>(PassToPrint).print(cout, &M);
163 // Get and print pass...
167 virtual const char *getPassName() const { return "'Pass' Printer"; }
169 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
170 AU.addRequiredID(PassToPrint);
171 AU.setPreservesAll();
175 char ModulePassPrinter::ID = 0;
176 struct FunctionPassPrinter : public FunctionPass {
177 const PassInfo *PassToPrint;
179 FunctionPassPrinter(const PassInfo *PI) : FunctionPass((intptr_t)&ID),
182 virtual bool runOnFunction(Function &F) {
184 cout << "Printing analysis '" << PassToPrint->getPassName()
185 << "' for function '" << F.getName() << "':\n";
187 // Get and print pass...
188 getAnalysisID<Pass>(PassToPrint).print(cout, F.getParent());
192 virtual const char *getPassName() const { return "FunctionPass Printer"; }
194 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
195 AU.addRequiredID(PassToPrint);
196 AU.setPreservesAll();
200 char FunctionPassPrinter::ID = 0;
202 struct LoopPassPrinter : public LoopPass {
204 const PassInfo *PassToPrint;
205 LoopPassPrinter(const PassInfo *PI) :
206 LoopPass((intptr_t)&ID), PassToPrint(PI) {}
208 virtual bool runOnLoop(Loop *L, LPPassManager &LPM) {
210 cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
211 getAnalysisID<Pass>(PassToPrint).print(cout,
212 L->getHeader()->getParent()->getParent());
214 // Get and print pass...
218 virtual const char *getPassName() const { return "'Pass' Printer"; }
220 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
221 AU.addRequiredID(PassToPrint);
222 AU.setPreservesAll();
226 char LoopPassPrinter::ID = 0;
228 struct BasicBlockPassPrinter : public BasicBlockPass {
229 const PassInfo *PassToPrint;
231 BasicBlockPassPrinter(const PassInfo *PI)
232 : BasicBlockPass((intptr_t)&ID), PassToPrint(PI) {}
234 virtual bool runOnBasicBlock(BasicBlock &BB) {
236 cout << "Printing Analysis info for BasicBlock '" << BB.getName()
237 << "': Pass " << PassToPrint->getPassName() << ":\n";
240 // Get and print pass...
241 getAnalysisID<Pass>(PassToPrint).print(cout, BB.getParent()->getParent());
245 virtual const char *getPassName() const { return "BasicBlockPass Printer"; }
247 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
248 AU.addRequiredID(PassToPrint);
249 AU.setPreservesAll();
253 char BasicBlockPassPrinter::ID = 0;
254 inline void addPass(PassManager &PM, Pass *P) {
255 // Add the pass to the pass manager...
258 // If we are verifying all of the intermediate steps, add the verifier...
259 if (VerifyEach) PM.add(createVerifierPass());
262 /// AddOptimizationPasses - This routine adds optimization passes
263 /// based on selected optimization level, OptLevel. This routine
264 /// duplicates llvm-gcc behaviour.
266 /// OptLevel - Optimization Level
267 void AddOptimizationPasses(PassManager &MPM, FunctionPassManager &FPM,
273 FPM.add(createCFGSimplificationPass());
275 FPM.add(createPromoteMemoryToRegisterPass());
277 FPM.add(createScalarReplAggregatesPass());
278 FPM.add(createInstructionCombiningPass());
281 MPM.add(createRaiseAllocationsPass()); // call %malloc -> malloc inst
282 MPM.add(createCFGSimplificationPass()); // Clean up disgusting code
283 MPM.add(createPromoteMemoryToRegisterPass()); // Kill useless allocas
285 MPM.add(createGlobalOptimizerPass()); // OptLevel out global vars
286 MPM.add(createGlobalDCEPass()); // Remove unused fns and globs
287 MPM.add(createIPConstantPropagationPass()); // IP Constant Propagation
288 MPM.add(createDeadArgEliminationPass()); // Dead argument elimination
290 MPM.add(createInstructionCombiningPass()); // Clean up after IPCP & DAE
291 MPM.add(createCFGSimplificationPass()); // Clean up after IPCP & DAE
293 MPM.add(createPruneEHPass()); // Remove dead EH info
294 MPM.add(createAddReadAttrsPass()); // Set readonly/readnone attrs
297 MPM.add(createFunctionInliningPass()); // Inline small functions
299 MPM.add(createArgumentPromotionPass()); // Scalarize uninlined fn args
300 if (!DisableSimplifyLibCalls)
301 MPM.add(createSimplifyLibCallsPass()); // Library Call Optimizations
302 MPM.add(createInstructionCombiningPass()); // Cleanup for scalarrepl.
303 MPM.add(createJumpThreadingPass()); // Thread jumps.
304 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
305 MPM.add(createScalarReplAggregatesPass()); // Break up aggregate allocas
306 MPM.add(createInstructionCombiningPass()); // Combine silly seq's
307 MPM.add(createCondPropagationPass()); // Propagate conditionals
308 MPM.add(createTailCallEliminationPass()); // Eliminate tail calls
309 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
310 MPM.add(createReassociatePass()); // Reassociate expressions
311 MPM.add(createLoopRotatePass()); // Rotate Loop
312 MPM.add(createLICMPass()); // Hoist loop invariants
313 MPM.add(createLoopUnswitchPass());
314 MPM.add(createLoopIndexSplitPass()); // Split loop index
315 MPM.add(createInstructionCombiningPass());
316 MPM.add(createIndVarSimplifyPass()); // Canonicalize indvars
317 MPM.add(createLoopDeletionPass()); // Delete dead loops
319 MPM.add(createLoopUnrollPass()); // Unroll small loops
320 MPM.add(createInstructionCombiningPass()); // Clean up after the unroller
321 MPM.add(createGVNPass()); // Remove redundancies
322 MPM.add(createMemCpyOptPass()); // Remove memcpy / form memset
323 MPM.add(createSCCPPass()); // Constant prop with SCCP
325 // Run instcombine after redundancy elimination to exploit opportunities
326 // opened up by them.
327 MPM.add(createInstructionCombiningPass());
328 MPM.add(createCondPropagationPass()); // Propagate conditionals
329 MPM.add(createDeadStoreEliminationPass()); // Delete dead stores
330 MPM.add(createAggressiveDCEPass()); // Delete dead instructions
331 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
334 MPM.add(createStripDeadPrototypesPass()); // Get rid of dead prototypes
335 MPM.add(createDeadTypeEliminationPass()); // Eliminate dead types
338 if (OptLevel > 1 && UnitAtATime)
339 MPM.add(createConstantMergePass()); // Merge dup global constants
344 void AddStandardCompilePasses(PassManager &PM) {
345 PM.add(createVerifierPass()); // Verify that input is correct
347 addPass(PM, createLowerSetJmpPass()); // Lower llvm.setjmp/.longjmp
349 // If the -strip-debug command line option was specified, do it.
351 addPass(PM, createStripSymbolsPass(true));
353 if (DisableOptimizations) return;
355 addPass(PM, createRaiseAllocationsPass()); // call %malloc -> malloc inst
356 addPass(PM, createCFGSimplificationPass()); // Clean up disgusting code
357 addPass(PM, createPromoteMemoryToRegisterPass());// Kill useless allocas
358 addPass(PM, createGlobalOptimizerPass()); // Optimize out global vars
359 addPass(PM, createGlobalDCEPass()); // Remove unused fns and globs
360 addPass(PM, createIPConstantPropagationPass());// IP Constant Propagation
361 addPass(PM, createDeadArgEliminationPass()); // Dead argument elimination
362 addPass(PM, createInstructionCombiningPass()); // Clean up after IPCP & DAE
363 addPass(PM, createCFGSimplificationPass()); // Clean up after IPCP & DAE
365 addPass(PM, createPruneEHPass()); // Remove dead EH info
366 addPass(PM, createAddReadAttrsPass()); // Set readonly/readnone attrs
369 addPass(PM, createFunctionInliningPass()); // Inline small functions
370 addPass(PM, createArgumentPromotionPass()); // Scalarize uninlined fn args
372 addPass(PM, createSimplifyLibCallsPass()); // Library Call Optimizations
373 addPass(PM, createInstructionCombiningPass()); // Cleanup for scalarrepl.
374 addPass(PM, createJumpThreadingPass()); // Thread jumps.
375 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
376 addPass(PM, createScalarReplAggregatesPass()); // Break up aggregate allocas
377 addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
378 addPass(PM, createCondPropagationPass()); // Propagate conditionals
380 addPass(PM, createTailCallEliminationPass()); // Eliminate tail calls
381 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
382 addPass(PM, createReassociatePass()); // Reassociate expressions
383 addPass(PM, createLoopRotatePass());
384 addPass(PM, createLICMPass()); // Hoist loop invariants
385 addPass(PM, createLoopUnswitchPass()); // Unswitch loops.
386 addPass(PM, createLoopIndexSplitPass()); // Index split loops.
387 // FIXME : Removing instcombine causes nestedloop regression.
388 addPass(PM, createInstructionCombiningPass());
389 addPass(PM, createIndVarSimplifyPass()); // Canonicalize indvars
390 addPass(PM, createLoopDeletionPass()); // Delete dead loops
391 addPass(PM, createLoopUnrollPass()); // Unroll small loops
392 addPass(PM, createInstructionCombiningPass()); // Clean up after the unroller
393 addPass(PM, createGVNPass()); // Remove redundancies
394 addPass(PM, createMemCpyOptPass()); // Remove memcpy / form memset
395 addPass(PM, createSCCPPass()); // Constant prop with SCCP
397 // Run instcombine after redundancy elimination to exploit opportunities
398 // opened up by them.
399 addPass(PM, createInstructionCombiningPass());
400 addPass(PM, createCondPropagationPass()); // Propagate conditionals
402 addPass(PM, createDeadStoreEliminationPass()); // Delete dead stores
403 addPass(PM, createAggressiveDCEPass()); // Delete dead instructions
404 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
405 addPass(PM, createStripDeadPrototypesPass()); // Get rid of dead prototypes
406 addPass(PM, createDeadTypeEliminationPass()); // Eliminate dead types
407 addPass(PM, createConstantMergePass()); // Merge dup global constants
410 } // anonymous namespace
413 //===----------------------------------------------------------------------===//
416 int main(int argc, char **argv) {
417 llvm_shutdown_obj X; // Call llvm_shutdown() on exit.
419 cl::ParseCommandLineOptions(argc, argv,
420 "llvm .bc -> .bc modular optimizer and analysis printer\n");
421 sys::PrintStackTraceOnErrorSignal();
423 // Allocate a full target machine description only if necessary.
424 // FIXME: The choice of target should be controllable on the command line.
425 std::auto_ptr<TargetMachine> target;
427 std::string ErrorMessage;
429 // Load the input module...
430 std::auto_ptr<Module> M;
431 if (MemoryBuffer *Buffer
432 = MemoryBuffer::getFileOrSTDIN(InputFilename, &ErrorMessage)) {
433 M.reset(ParseBitcodeFile(Buffer, &ErrorMessage));
438 cerr << argv[0] << ": ";
439 if (ErrorMessage.size())
440 cerr << ErrorMessage << "\n";
442 cerr << "bitcode didn't read correctly.\n";
446 // Figure out what stream we are supposed to write to...
447 // FIXME: cout is not binary!
448 std::ostream *Out = &std::cout; // Default to printing to stdout...
449 if (OutputFilename != "-") {
450 if (!Force && std::ifstream(OutputFilename.c_str())) {
451 // If force is not specified, make sure not to overwrite a file!
452 cerr << argv[0] << ": error opening '" << OutputFilename
453 << "': file exists!\n"
454 << "Use -f command line argument to force output\n";
457 std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
459 Out = new std::ofstream(OutputFilename.c_str(), io_mode);
462 cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
466 // Make sure that the Output file gets unlinked from the disk if we get a
468 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
471 // If the output is set to be emitted to standard out, and standard out is a
472 // console, print out a warning message and refuse to do it. We don't
473 // impress anyone by spewing tons of binary goo to a terminal.
474 if (!Force && !NoOutput && CheckBitcodeOutputToConsole(Out,!Quiet)) {
478 // Create a PassManager to hold and optimize the collection of passes we are
483 // Add an appropriate TargetData instance for this module...
484 Passes.add(new TargetData(M.get()));
486 FunctionPassManager *FPasses = NULL;
487 if (OptLevelO1 || OptLevelO2 || OptLevelO3) {
488 FPasses = new FunctionPassManager(new ExistingModuleProvider(M.get()));
489 FPasses->add(new TargetData(M.get()));
492 // If the -strip-debug command line option was specified, add it. If
493 // -std-compile-opts was also specified, it will handle StripDebug.
494 if (StripDebug && !StandardCompileOpts)
495 addPass(Passes, createStripSymbolsPass(true));
497 // Create a new optimization pass for each one specified on the command line
498 for (unsigned i = 0; i < PassList.size(); ++i) {
499 // Check to see if -std-compile-opts was specified before this option. If
501 if (StandardCompileOpts &&
502 StandardCompileOpts.getPosition() < PassList.getPosition(i)) {
503 AddStandardCompilePasses(Passes);
504 StandardCompileOpts = false;
507 if (OptLevelO1 && OptLevelO1.getPosition() < PassList.getPosition(i)) {
508 AddOptimizationPasses(Passes, *FPasses, 1);
512 if (OptLevelO2 && OptLevelO2.getPosition() < PassList.getPosition(i)) {
513 AddOptimizationPasses(Passes, *FPasses, 2);
517 if (OptLevelO3 && OptLevelO3.getPosition() < PassList.getPosition(i)) {
518 AddOptimizationPasses(Passes, *FPasses, 3);
522 const PassInfo *PassInf = PassList[i];
524 if (PassInf->getNormalCtor())
525 P = PassInf->getNormalCtor()();
527 cerr << argv[0] << ": cannot create pass: "
528 << PassInf->getPassName() << "\n";
533 if (dynamic_cast<BasicBlockPass*>(P))
534 Passes.add(new BasicBlockPassPrinter(PassInf));
535 else if (dynamic_cast<LoopPass*>(P))
536 Passes.add(new LoopPassPrinter(PassInf));
537 else if (dynamic_cast<FunctionPass*>(P))
538 Passes.add(new FunctionPassPrinter(PassInf));
539 else if (dynamic_cast<CallGraphSCCPass*>(P))
540 Passes.add(new CallGraphSCCPassPrinter(PassInf));
542 Passes.add(new ModulePassPrinter(PassInf));
547 Passes.add(createPrintModulePass(&errs()));
550 // If -std-compile-opts was specified at the end of the pass list, add them.
551 if (StandardCompileOpts) {
552 AddStandardCompilePasses(Passes);
553 StandardCompileOpts = false;
557 AddOptimizationPasses(Passes, *FPasses, 1);
561 AddOptimizationPasses(Passes, *FPasses, 2);
565 AddOptimizationPasses(Passes, *FPasses, 3);
568 if (OptLevelO1 || OptLevelO2 || OptLevelO3) {
569 for (Module::iterator I = M.get()->begin(), E = M.get()->end();
574 // Check that the module is well formed on completion of optimization
575 if (!NoVerify && !VerifyEach)
576 Passes.add(createVerifierPass());
578 // Write bitcode out to disk or cout as the last step...
579 if (!NoOutput && !AnalyzeOnly)
580 Passes.add(CreateBitcodeWriterPass(*Out));
582 // Now that we have all of the passes ready, run them.
583 Passes.run(*M.get());
585 // Delete the ofstream.
586 if (Out != &std::cout)
590 } catch (const std::string& msg) {
591 cerr << argv[0] << ": " << msg << "\n";
593 cerr << argv[0] << ": Unexpected unknown exception occurred.\n";