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/PassManager.h"
17 #include "llvm/CallGraphSCCPass.h"
18 #include "llvm/Bitcode/ReaderWriter.h"
19 #include "llvm/Assembly/PrintModulePass.h"
20 #include "llvm/Analysis/Verifier.h"
21 #include "llvm/Analysis/LoopPass.h"
22 #include "llvm/Analysis/CallGraph.h"
23 #include "llvm/Target/TargetData.h"
24 #include "llvm/Target/TargetMachine.h"
25 #include "llvm/Target/TargetMachineRegistry.h"
26 #include "llvm/Target/SubtargetFeature.h"
27 #include "llvm/Support/PassNameParser.h"
28 #include "llvm/System/Signals.h"
29 #include "llvm/Support/ManagedStatic.h"
30 #include "llvm/Support/MemoryBuffer.h"
31 #include "llvm/Support/PluginLoader.h"
32 #include "llvm/Support/Streams.h"
33 #include "llvm/Support/SystemUtils.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"));
90 Quiet("q", cl::desc("Obsolete option"), cl::Hidden);
93 QuietA("quiet", cl::desc("Alias for -q"), cl::aliasopt(Quiet));
96 AnalyzeOnly("analyze", cl::desc("Only perform analysis, no optimization"));
98 static cl::opt<const TargetMachineRegistry::entry*, false,
99 TargetMachineRegistry::Parser>
100 MArch("march", cl::desc("Architecture to generate code for:"));
102 static cl::opt<std::string>
104 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
105 cl::value_desc("cpu-name"),
108 static cl::list<std::string>
111 cl::desc("Target specific attributes (-mattr=help for details)"),
112 cl::value_desc("a1,+a2,-a3,..."));
114 // ---------- Define Printers for module and function passes ------------
117 struct CallGraphSCCPassPrinter : public CallGraphSCCPass {
119 const PassInfo *PassToPrint;
120 CallGraphSCCPassPrinter(const PassInfo *PI) :
121 CallGraphSCCPass((intptr_t)&ID), PassToPrint(PI) {}
123 virtual bool runOnSCC(const std::vector<CallGraphNode *>&SCC) {
125 cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
127 for (unsigned i = 0, e = SCC.size(); i != e; ++i) {
128 Function *F = SCC[i]->getFunction();
130 getAnalysisID<Pass>(PassToPrint).print(cout, F->getParent());
133 // Get and print pass...
137 virtual const char *getPassName() const { return "'Pass' Printer"; }
139 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
140 AU.addRequiredID(PassToPrint);
141 AU.setPreservesAll();
145 char CallGraphSCCPassPrinter::ID = 0;
147 struct ModulePassPrinter : public ModulePass {
149 const PassInfo *PassToPrint;
150 ModulePassPrinter(const PassInfo *PI) : ModulePass((intptr_t)&ID),
153 virtual bool runOnModule(Module &M) {
155 cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
156 getAnalysisID<Pass>(PassToPrint).print(cout, &M);
159 // Get and print pass...
163 virtual const char *getPassName() const { return "'Pass' Printer"; }
165 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
166 AU.addRequiredID(PassToPrint);
167 AU.setPreservesAll();
171 char ModulePassPrinter::ID = 0;
172 struct FunctionPassPrinter : public FunctionPass {
173 const PassInfo *PassToPrint;
175 FunctionPassPrinter(const PassInfo *PI) : FunctionPass((intptr_t)&ID),
178 virtual bool runOnFunction(Function &F) {
180 cout << "Printing analysis '" << PassToPrint->getPassName()
181 << "' for function '" << F.getName() << "':\n";
183 // Get and print pass...
184 getAnalysisID<Pass>(PassToPrint).print(cout, F.getParent());
188 virtual const char *getPassName() const { return "FunctionPass Printer"; }
190 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
191 AU.addRequiredID(PassToPrint);
192 AU.setPreservesAll();
196 char FunctionPassPrinter::ID = 0;
198 struct LoopPassPrinter : public LoopPass {
200 const PassInfo *PassToPrint;
201 LoopPassPrinter(const PassInfo *PI) :
202 LoopPass((intptr_t)&ID), PassToPrint(PI) {}
204 virtual bool runOnLoop(Loop *L, LPPassManager &LPM) {
206 cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
207 getAnalysisID<Pass>(PassToPrint).print(cout,
208 L->getHeader()->getParent()->getParent());
210 // Get and print pass...
214 virtual const char *getPassName() const { return "'Pass' Printer"; }
216 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
217 AU.addRequiredID(PassToPrint);
218 AU.setPreservesAll();
222 char LoopPassPrinter::ID = 0;
224 struct BasicBlockPassPrinter : public BasicBlockPass {
225 const PassInfo *PassToPrint;
227 BasicBlockPassPrinter(const PassInfo *PI)
228 : BasicBlockPass((intptr_t)&ID), PassToPrint(PI) {}
230 virtual bool runOnBasicBlock(BasicBlock &BB) {
232 cout << "Printing Analysis info for BasicBlock '" << BB.getName()
233 << "': Pass " << PassToPrint->getPassName() << ":\n";
236 // Get and print pass...
237 getAnalysisID<Pass>(PassToPrint).print(cout, BB.getParent()->getParent());
241 virtual const char *getPassName() const { return "BasicBlockPass Printer"; }
243 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
244 AU.addRequiredID(PassToPrint);
245 AU.setPreservesAll();
249 char BasicBlockPassPrinter::ID = 0;
250 inline void addPass(PassManager &PM, Pass *P) {
251 // Add the pass to the pass manager...
254 // If we are verifying all of the intermediate steps, add the verifier...
255 if (VerifyEach) PM.add(createVerifierPass());
258 void AddStandardCompilePasses(PassManager &PM) {
259 PM.add(createVerifierPass()); // Verify that input is correct
261 addPass(PM, createLowerSetJmpPass()); // Lower llvm.setjmp/.longjmp
263 // If the -strip-debug command line option was specified, do it.
265 addPass(PM, createStripSymbolsPass(true));
267 if (DisableOptimizations) return;
269 addPass(PM, createRaiseAllocationsPass()); // call %malloc -> malloc inst
270 addPass(PM, createCFGSimplificationPass()); // Clean up disgusting code
271 addPass(PM, createPromoteMemoryToRegisterPass());// Kill useless allocas
272 addPass(PM, createGlobalOptimizerPass()); // Optimize out global vars
273 addPass(PM, createGlobalDCEPass()); // Remove unused fns and globs
274 addPass(PM, createIPConstantPropagationPass());// IP Constant Propagation
275 addPass(PM, createDeadArgEliminationPass()); // Dead argument elimination
276 addPass(PM, createInstructionCombiningPass()); // Clean up after IPCP & DAE
277 addPass(PM, createCFGSimplificationPass()); // Clean up after IPCP & DAE
279 addPass(PM, createPruneEHPass()); // Remove dead EH info
282 addPass(PM, createFunctionInliningPass()); // Inline small functions
283 addPass(PM, createArgumentPromotionPass()); // Scalarize uninlined fn args
285 addPass(PM, createSimplifyLibCallsPass()); // Library Call Optimizations
286 addPass(PM, createInstructionCombiningPass()); // Cleanup for scalarrepl.
287 addPass(PM, createJumpThreadingPass()); // Thread jumps.
288 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
289 addPass(PM, createScalarReplAggregatesPass()); // Break up aggregate allocas
290 addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
291 addPass(PM, createCondPropagationPass()); // Propagate conditionals
293 addPass(PM, createTailCallEliminationPass()); // Eliminate tail calls
294 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
295 addPass(PM, createReassociatePass()); // Reassociate expressions
296 addPass(PM, createLoopRotatePass());
297 addPass(PM, createLICMPass()); // Hoist loop invariants
298 addPass(PM, createLoopUnswitchPass()); // Unswitch loops.
299 addPass(PM, createLoopIndexSplitPass()); // Index split loops.
300 // FIXME : Removing instcombine causes nestedloop regression.
301 addPass(PM, createInstructionCombiningPass());
302 addPass(PM, createIndVarSimplifyPass()); // Canonicalize indvars
303 addPass(PM, createLoopDeletionPass()); // Delete dead loops
304 addPass(PM, createLoopUnrollPass()); // Unroll small loops
305 addPass(PM, createInstructionCombiningPass()); // Clean up after the unroller
306 addPass(PM, createGVNPass()); // Remove redundancies
307 addPass(PM, createMemCpyOptPass()); // Remove memcpy / form memset
308 addPass(PM, createSCCPPass()); // Constant prop with SCCP
310 // Run instcombine after redundancy elimination to exploit opportunities
311 // opened up by them.
312 addPass(PM, createInstructionCombiningPass());
313 addPass(PM, createCondPropagationPass()); // Propagate conditionals
315 addPass(PM, createDeadStoreEliminationPass()); // Delete dead stores
316 addPass(PM, createAggressiveDCEPass()); // Delete dead instructions
317 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
318 addPass(PM, createStripDeadPrototypesPass()); // Get rid of dead prototypes
319 addPass(PM, createDeadTypeEliminationPass()); // Eliminate dead types
320 addPass(PM, createConstantMergePass()); // Merge dup global constants
323 } // anonymous namespace
326 //===----------------------------------------------------------------------===//
330 TargetMachine *getTargetMachine(Module &Mod) {
335 TargetMachineRegistry::getClosestStaticTargetForModule(Mod, Err);
337 std::cerr << "Error auto-selecting target for module '"
338 << Err << "'. Please use the -march option to explicitly "
339 << "pick a target.\n";
344 // Package up features to be passed to target/subtarget
345 std::string FeaturesStr;
346 if (MCPU.size() || MAttrs.size()) {
347 SubtargetFeatures Features;
348 Features.setCPU(MCPU);
349 for (unsigned i = 0; i != MAttrs.size(); ++i)
350 Features.AddFeature(MAttrs[i]);
351 FeaturesStr = Features.getString();
354 TargetMachine *Target = MArch->CtorFn(Mod, FeaturesStr);
355 assert(Target && "Could not allocate target machine!");
359 int main(int argc, char **argv) {
360 llvm_shutdown_obj X; // Call llvm_shutdown() on exit.
362 cl::ParseCommandLineOptions(argc, argv,
363 "llvm .bc -> .bc modular optimizer and analysis printer\n");
364 sys::PrintStackTraceOnErrorSignal();
366 std::string ErrorMessage;
368 // Load the input module...
369 std::auto_ptr<Module> M;
370 if (MemoryBuffer *Buffer
371 = MemoryBuffer::getFileOrSTDIN(InputFilename, &ErrorMessage)) {
372 M.reset(ParseBitcodeFile(Buffer, &ErrorMessage));
377 cerr << argv[0] << ": ";
378 if (ErrorMessage.size())
379 cerr << ErrorMessage << "\n";
381 cerr << "bitcode didn't read correctly.\n";
385 // Figure out what stream we are supposed to write to...
386 // FIXME: cout is not binary!
387 std::ostream *Out = &std::cout; // Default to printing to stdout...
388 if (OutputFilename != "-") {
389 if (!Force && std::ifstream(OutputFilename.c_str())) {
390 // If force is not specified, make sure not to overwrite a file!
391 cerr << argv[0] << ": error opening '" << OutputFilename
392 << "': file exists!\n"
393 << "Use -f command line argument to force output\n";
396 std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
398 Out = new std::ofstream(OutputFilename.c_str(), io_mode);
401 cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
405 // Make sure that the Output file gets unlinked from the disk if we get a
407 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
410 // If the output is set to be emitted to standard out, and standard out is a
411 // console, print out a warning message and refuse to do it. We don't
412 // impress anyone by spewing tons of binary goo to a terminal.
413 if (!Force && !NoOutput && CheckBitcodeOutputToConsole(Out,!Quiet)) {
417 // Create a PassManager to hold and optimize the collection of passes we are
422 // Add an appropriate TargetData instance for this module...
423 Passes.add(new TargetData(M.get()));
425 // If the -strip-debug command line option was specified, add it. If
426 // -std-compile-opts was also specified, it will handle StripDebug.
427 if (StripDebug && !StandardCompileOpts)
428 addPass(Passes, createStripSymbolsPass(true));
430 // Create a new optimization pass for each one specified on the command line
431 for (unsigned i = 0; i < PassList.size(); ++i) {
432 // Check to see if -std-compile-opts was specified before this option. If
434 if (StandardCompileOpts &&
435 StandardCompileOpts.getPosition() < PassList.getPosition(i)) {
436 AddStandardCompilePasses(Passes);
437 StandardCompileOpts = false;
440 const PassInfo *PassInf = PassList[i];
442 if (PassInf->getNormalCtor())
443 P = PassInf->getNormalCtor()();
445 cerr << argv[0] << ": cannot create pass: "
446 << PassInf->getPassName() << "\n";
451 if (dynamic_cast<BasicBlockPass*>(P))
452 Passes.add(new BasicBlockPassPrinter(PassInf));
453 else if (dynamic_cast<LoopPass*>(P))
454 Passes.add(new LoopPassPrinter(PassInf));
455 else if (dynamic_cast<FunctionPass*>(P))
456 Passes.add(new FunctionPassPrinter(PassInf));
457 else if (dynamic_cast<CallGraphSCCPass*>(P))
458 Passes.add(new CallGraphSCCPassPrinter(PassInf));
460 Passes.add(new ModulePassPrinter(PassInf));
465 Passes.add(new PrintModulePass(&cerr));
468 // If -std-compile-opts was specified at the end of the pass list, add them.
469 if (StandardCompileOpts) {
470 AddStandardCompilePasses(Passes);
471 StandardCompileOpts = false;
474 // Check that the module is well formed on completion of optimization
475 if (!NoVerify && !VerifyEach)
476 Passes.add(createVerifierPass());
478 // Write bitcode out to disk or cout as the last step...
479 if (!NoOutput && !AnalyzeOnly)
480 Passes.add(CreateBitcodeWriterPass(*Out));
482 // Now that we have all of the passes ready, run them.
483 Passes.run(*M.get());
485 // Delete the ofstream.
486 if (Out != &std::cout)
490 } catch (const std::string& msg) {
491 cerr << argv[0] << ": " << msg << "\n";
493 cerr << argv[0] << ": Unexpected unknown exception occurred.\n";