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/Bytecode/Reader.h"
18 #include "llvm/Bytecode/WriteBytecodePass.h"
19 #include "llvm/Assembly/PrintModulePass.h"
20 #include "llvm/Analysis/Verifier.h"
21 #include "llvm/Analysis/LoopPass.h"
22 #include "llvm/Target/TargetData.h"
23 #include "llvm/Target/TargetMachine.h"
24 #include "llvm/Support/PassNameParser.h"
25 #include "llvm/System/Signals.h"
26 #include "llvm/Support/ManagedStatic.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 static cl::opt<bool> NoCompress("disable-compression", cl::init(true),
45 cl::desc("Don't compress the generated bytecode"));
47 // Other command line options...
49 static cl::opt<std::string>
50 InputFilename(cl::Positional, cl::desc("<input bytecode file>"),
51 cl::init("-"), cl::value_desc("filename"));
53 static cl::opt<std::string>
54 OutputFilename("o", cl::desc("Override output filename"),
55 cl::value_desc("filename"), cl::init("-"));
58 Force("f", cl::desc("Overwrite output files"));
61 PrintEachXForm("p", cl::desc("Print module after each transformation"));
64 NoOutput("disable-output",
65 cl::desc("Do not write result bytecode file"), cl::Hidden);
68 NoVerify("disable-verify", cl::desc("Do not verify result module"), cl::Hidden);
71 VerifyEach("verify-each", cl::desc("Verify after each transform"));
74 StripDebug("strip-debug",
75 cl::desc("Strip debugger symbol info from translation unit"));
78 DisableInline("disable-inlining", cl::desc("Do not run the inliner pass"));
81 DisableOptimizations("disable-opt",
82 cl::desc("Do not run any optimization passes"));
85 StandardCompileOpts("std-compile-opts",
86 cl::desc("Include the standard compile time optimizations"));
89 Quiet("q", cl::desc("Obsolete option"), cl::Hidden);
92 QuietA("quiet", cl::desc("Alias for -q"), cl::aliasopt(Quiet));
95 AnalyzeOnly("analyze", cl::desc("Only perform analysis, no optimization"));
97 // ---------- Define Printers for module and function passes ------------
100 struct ModulePassPrinter : public ModulePass {
101 const PassInfo *PassToPrint;
102 ModulePassPrinter(const PassInfo *PI) : PassToPrint(PI) {}
104 virtual bool runOnModule(Module &M) {
106 cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
107 getAnalysisID<Pass>(PassToPrint).print(cout, &M);
110 // Get and print pass...
114 virtual const char *getPassName() const { return "'Pass' Printer"; }
116 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
117 AU.addRequiredID(PassToPrint);
118 AU.setPreservesAll();
122 struct FunctionPassPrinter : public FunctionPass {
123 const PassInfo *PassToPrint;
124 FunctionPassPrinter(const PassInfo *PI) : PassToPrint(PI) {}
126 virtual bool runOnFunction(Function &F) {
128 cout << "Printing analysis '" << PassToPrint->getPassName()
129 << "' for function '" << F.getName() << "':\n";
131 // Get and print pass...
132 getAnalysisID<Pass>(PassToPrint).print(cout, F.getParent());
136 virtual const char *getPassName() const { return "FunctionPass Printer"; }
138 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
139 AU.addRequiredID(PassToPrint);
140 AU.setPreservesAll();
144 struct BasicBlockPassPrinter : public BasicBlockPass {
145 const PassInfo *PassToPrint;
146 BasicBlockPassPrinter(const PassInfo *PI) : PassToPrint(PI) {}
148 virtual bool runOnBasicBlock(BasicBlock &BB) {
150 cout << "Printing Analysis info for BasicBlock '" << BB.getName()
151 << "': Pass " << PassToPrint->getPassName() << ":\n";
154 // Get and print pass...
155 getAnalysisID<Pass>(PassToPrint).print(cout, BB.getParent()->getParent());
159 virtual const char *getPassName() const { return "BasicBlockPass Printer"; }
161 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
162 AU.addRequiredID(PassToPrint);
163 AU.setPreservesAll();
167 inline void addPass(PassManager &PM, Pass *P) {
168 // Add the pass to the pass manager...
171 // If we are verifying all of the intermediate steps, add the verifier...
172 if (VerifyEach) PM.add(createVerifierPass());
175 void AddStandardCompilePasses(PassManager &PM) {
176 PM.add(createVerifierPass()); // Verify that input is correct
178 addPass(PM, createLowerSetJmpPass()); // Lower llvm.setjmp/.longjmp
180 // If the -strip-debug command line option was specified, do it.
182 addPass(PM, createStripSymbolsPass(true));
184 if (DisableOptimizations) return;
186 addPass(PM, createRaiseAllocationsPass()); // call %malloc -> malloc inst
187 addPass(PM, createCFGSimplificationPass()); // Clean up disgusting code
188 addPass(PM, createPromoteMemoryToRegisterPass());// Kill useless allocas
189 addPass(PM, createGlobalOptimizerPass()); // Optimize out global vars
190 addPass(PM, createGlobalDCEPass()); // Remove unused fns and globs
191 addPass(PM, createIPConstantPropagationPass());// IP Constant Propagation
192 addPass(PM, createDeadArgEliminationPass()); // Dead argument elimination
193 addPass(PM, createInstructionCombiningPass()); // Clean up after IPCP & DAE
194 addPass(PM, createCFGSimplificationPass()); // Clean up after IPCP & DAE
196 addPass(PM, createPruneEHPass()); // Remove dead EH info
199 addPass(PM, createFunctionInliningPass()); // Inline small functions
200 addPass(PM, createArgumentPromotionPass()); // Scalarize uninlined fn args
202 addPass(PM, createTailDuplicationPass()); // Simplify cfg by copying code
203 addPass(PM, createInstructionCombiningPass()); // Cleanup for scalarrepl.
204 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
205 addPass(PM, createScalarReplAggregatesPass()); // Break up aggregate allocas
206 addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
207 addPass(PM, createCondPropagationPass()); // Propagate conditionals
209 addPass(PM, createTailCallEliminationPass()); // Eliminate tail calls
210 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
211 addPass(PM, createReassociatePass()); // Reassociate expressions
212 addPass(PM, createLoopRotatePass());
213 addPass(PM, createLICMPass()); // Hoist loop invariants
214 addPass(PM, createLoopUnswitchPass()); // Unswitch loops.
215 addPass(PM, createInstructionCombiningPass()); // Clean up after LICM/reassoc
216 addPass(PM, createIndVarSimplifyPass()); // Canonicalize indvars
217 addPass(PM, createLoopUnrollPass()); // Unroll small loops
218 addPass(PM, createInstructionCombiningPass()); // Clean up after the unroller
219 addPass(PM, createLoadValueNumberingPass()); // GVN for load instructions
220 addPass(PM, createGCSEPass()); // Remove common subexprs
221 addPass(PM, createSCCPPass()); // Constant prop with SCCP
223 // Run instcombine after redundancy elimination to exploit opportunities
224 // opened up by them.
225 addPass(PM, createInstructionCombiningPass());
226 addPass(PM, createCondPropagationPass()); // Propagate conditionals
228 addPass(PM, createDeadStoreEliminationPass()); // Delete dead stores
229 addPass(PM, createAggressiveDCEPass()); // SSA based 'Aggressive DCE'
230 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
231 addPass(PM, createSimplifyLibCallsPass()); // Library Call Optimizations
232 addPass(PM, createDeadTypeEliminationPass()); // Eliminate dead types
233 addPass(PM, createConstantMergePass()); // Merge dup global constants
236 } // anonymous namespace
239 //===----------------------------------------------------------------------===//
242 int main(int argc, char **argv) {
243 llvm_shutdown_obj X; // Call llvm_shutdown() on exit.
245 cl::ParseCommandLineOptions(argc, argv,
246 " llvm .bc -> .bc modular optimizer and analysis printer \n");
247 sys::PrintStackTraceOnErrorSignal();
249 // Allocate a full target machine description only if necessary.
250 // FIXME: The choice of target should be controllable on the command line.
251 std::auto_ptr<TargetMachine> target;
253 std::string ErrorMessage;
255 // Load the input module...
256 std::auto_ptr<Module> M(ParseBytecodeFile(InputFilename,
257 Compressor::decompressToNewBuffer, &ErrorMessage));
259 cerr << argv[0] << ": ";
260 if (ErrorMessage.size())
261 cerr << ErrorMessage << "\n";
263 cerr << "bytecode didn't read correctly.\n";
267 // Figure out what stream we are supposed to write to...
268 // FIXME: cout is not binary!
269 std::ostream *Out = &std::cout; // Default to printing to stdout...
270 if (OutputFilename != "-") {
271 if (!Force && std::ifstream(OutputFilename.c_str())) {
272 // If force is not specified, make sure not to overwrite a file!
273 cerr << argv[0] << ": error opening '" << OutputFilename
274 << "': file exists!\n"
275 << "Use -f command line argument to force output\n";
278 std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
280 Out = new std::ofstream(OutputFilename.c_str(), io_mode);
283 cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
287 // Make sure that the Output file gets unlinked from the disk if we get a
289 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
292 // If the output is set to be emitted to standard out, and standard out is a
293 // console, print out a warning message and refuse to do it. We don't
294 // impress anyone by spewing tons of binary goo to a terminal.
295 if (!Force && !NoOutput && CheckBytecodeOutputToConsole(Out,!Quiet)) {
299 // Create a PassManager to hold and optimize the collection of passes we are
304 // Add an appropriate TargetData instance for this module...
305 Passes.add(new TargetData(M.get()));
307 // If -std-compile-opts is given, add in all the standard compilation
308 // optimizations first. This will handle -strip-debug, -disable-inline,
309 // and -disable-opt as well.
310 if (StandardCompileOpts)
311 AddStandardCompilePasses(Passes);
313 // otherwise if the -strip-debug command line option was specified, add it.
315 addPass(Passes, createStripSymbolsPass(true));
317 // Create a new optimization pass for each one specified on the command line
318 for (unsigned i = 0; i < PassList.size(); ++i) {
319 const PassInfo *PassInf = PassList[i];
321 if (PassInf->getNormalCtor())
322 P = PassInf->getNormalCtor()();
324 cerr << argv[0] << ": cannot create pass: "
325 << PassInf->getPassName() << "\n";
330 if (dynamic_cast<BasicBlockPass*>(P))
331 Passes.add(new BasicBlockPassPrinter(PassInf));
332 else if (dynamic_cast<FunctionPass*>(P))
333 Passes.add(new FunctionPassPrinter(PassInf));
335 Passes.add(new ModulePassPrinter(PassInf));
340 Passes.add(new PrintModulePass(&cerr));
343 // Check that the module is well formed on completion of optimization
344 if (!NoVerify && !VerifyEach)
345 Passes.add(createVerifierPass());
347 // Write bytecode out to disk or cout as the last step...
349 if (!NoOutput && !AnalyzeOnly)
350 Passes.add(new WriteBytecodePass(&L, false, !NoCompress));
352 // Now that we have all of the passes ready, run them.
353 Passes.run(*M.get());
357 } catch (const std::string& msg) {
358 cerr << argv[0] << ": " << msg << "\n";
360 cerr << argv[0] << ": Unexpected unknown exception occurred.\n";