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/Support/Timer.h"
31 #include "llvm/LinkAllPasses.h"
32 #include "llvm/LinkAllVMCore.h"
39 // The OptimizationList is automatically populated with registered Passes by the
42 static cl::list<const PassInfo*, bool, PassNameParser>
43 PassList(cl::desc("Optimizations available:"));
45 static cl::opt<bool> NoCompress("disable-compression", cl::init(true),
46 cl::desc("Don't compress the generated bytecode"));
48 // Other command line options...
50 static cl::opt<std::string>
51 InputFilename(cl::Positional, cl::desc("<input bytecode 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 bytecode 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 Timer BytecodeLoadTimer("Bytecode Loader");
100 // ---------- Define Printers for module and function passes ------------
103 struct ModulePassPrinter : public ModulePass {
104 const PassInfo *PassToPrint;
105 ModulePassPrinter(const PassInfo *PI) : PassToPrint(PI) {}
107 virtual bool runOnModule(Module &M) {
109 cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
110 getAnalysisID<Pass>(PassToPrint).print(cout, &M);
113 // Get and print pass...
117 virtual const char *getPassName() const { return "'Pass' Printer"; }
119 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
120 AU.addRequiredID(PassToPrint);
121 AU.setPreservesAll();
125 struct FunctionPassPrinter : public FunctionPass {
126 const PassInfo *PassToPrint;
127 FunctionPassPrinter(const PassInfo *PI) : PassToPrint(PI) {}
129 virtual bool runOnFunction(Function &F) {
131 cout << "Printing analysis '" << PassToPrint->getPassName()
132 << "' for function '" << F.getName() << "':\n";
134 // Get and print pass...
135 getAnalysisID<Pass>(PassToPrint).print(cout, F.getParent());
139 virtual const char *getPassName() const { return "FunctionPass Printer"; }
141 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
142 AU.addRequiredID(PassToPrint);
143 AU.setPreservesAll();
147 struct BasicBlockPassPrinter : public BasicBlockPass {
148 const PassInfo *PassToPrint;
149 BasicBlockPassPrinter(const PassInfo *PI) : PassToPrint(PI) {}
151 virtual bool runOnBasicBlock(BasicBlock &BB) {
153 cout << "Printing Analysis info for BasicBlock '" << BB.getName()
154 << "': Pass " << PassToPrint->getPassName() << ":\n";
157 // Get and print pass...
158 getAnalysisID<Pass>(PassToPrint).print(cout, BB.getParent()->getParent());
162 virtual const char *getPassName() const { return "BasicBlockPass Printer"; }
164 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
165 AU.addRequiredID(PassToPrint);
166 AU.setPreservesAll();
170 inline void addPass(PassManager &PM, Pass *P) {
171 // Add the pass to the pass manager...
174 // If we are verifying all of the intermediate steps, add the verifier...
175 if (VerifyEach) PM.add(createVerifierPass());
178 void AddStandardCompilePasses(PassManager &PM) {
179 PM.add(createVerifierPass()); // Verify that input is correct
181 addPass(PM, createLowerSetJmpPass()); // Lower llvm.setjmp/.longjmp
183 // If the -strip-debug command line option was specified, do it.
185 addPass(PM, createStripSymbolsPass(true));
187 if (DisableOptimizations) return;
189 addPass(PM, createRaiseAllocationsPass()); // call %malloc -> malloc inst
190 addPass(PM, createCFGSimplificationPass()); // Clean up disgusting code
191 addPass(PM, createPromoteMemoryToRegisterPass());// Kill useless allocas
192 addPass(PM, createGlobalOptimizerPass()); // Optimize out global vars
193 addPass(PM, createGlobalDCEPass()); // Remove unused fns and globs
194 addPass(PM, createIPConstantPropagationPass());// IP Constant Propagation
195 addPass(PM, createDeadArgEliminationPass()); // Dead argument elimination
196 addPass(PM, createInstructionCombiningPass()); // Clean up after IPCP & DAE
197 addPass(PM, createCFGSimplificationPass()); // Clean up after IPCP & DAE
199 addPass(PM, createPruneEHPass()); // Remove dead EH info
202 addPass(PM, createFunctionInliningPass()); // Inline small functions
203 addPass(PM, createArgumentPromotionPass()); // Scalarize uninlined fn args
205 addPass(PM, createTailDuplicationPass()); // Simplify cfg by copying code
206 addPass(PM, createInstructionCombiningPass()); // Cleanup for scalarrepl.
207 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
208 addPass(PM, createScalarReplAggregatesPass()); // Break up aggregate allocas
209 addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
210 addPass(PM, createCondPropagationPass()); // Propagate conditionals
212 addPass(PM, createTailCallEliminationPass()); // Eliminate tail calls
213 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
214 addPass(PM, createReassociatePass()); // Reassociate expressions
215 addPass(PM, createLoopRotatePass());
216 addPass(PM, createLICMPass()); // Hoist loop invariants
217 addPass(PM, createLoopUnswitchPass()); // Unswitch loops.
218 addPass(PM, createInstructionCombiningPass()); // Clean up after LICM/reassoc
219 addPass(PM, createIndVarSimplifyPass()); // Canonicalize indvars
220 addPass(PM, createLoopUnrollPass()); // Unroll small loops
221 addPass(PM, createInstructionCombiningPass()); // Clean up after the unroller
222 addPass(PM, createLoadValueNumberingPass()); // GVN for load instructions
223 addPass(PM, createGCSEPass()); // Remove common subexprs
224 addPass(PM, createSCCPPass()); // Constant prop with SCCP
226 // Run instcombine after redundancy elimination to exploit opportunities
227 // opened up by them.
228 addPass(PM, createInstructionCombiningPass());
229 addPass(PM, createCondPropagationPass()); // Propagate conditionals
231 addPass(PM, createDeadStoreEliminationPass()); // Delete dead stores
232 addPass(PM, createAggressiveDCEPass()); // SSA based 'Aggressive DCE'
233 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
234 addPass(PM, createSimplifyLibCallsPass()); // Library Call Optimizations
235 addPass(PM, createDeadTypeEliminationPass()); // Eliminate dead types
236 addPass(PM, createConstantMergePass()); // Merge dup global constants
239 } // anonymous namespace
242 //===----------------------------------------------------------------------===//
245 int main(int argc, char **argv) {
246 llvm_shutdown_obj X; // Call llvm_shutdown() on exit.
248 cl::ParseCommandLineOptions(argc, argv,
249 " llvm .bc -> .bc modular optimizer and analysis printer \n");
250 sys::PrintStackTraceOnErrorSignal();
252 // Allocate a full target machine description only if necessary.
253 // FIXME: The choice of target should be controllable on the command line.
254 std::auto_ptr<TargetMachine> target;
256 std::string ErrorMessage;
258 // Load the input module...
259 std::auto_ptr<Module> M(ParseBytecodeFile(InputFilename,
260 Compressor::decompressToNewBuffer, &ErrorMessage));
262 cerr << argv[0] << ": ";
263 if (ErrorMessage.size())
264 cerr << ErrorMessage << "\n";
266 cerr << "bytecode didn't read correctly.\n";
270 // Figure out what stream we are supposed to write to...
271 // FIXME: cout is not binary!
272 std::ostream *Out = &std::cout; // Default to printing to stdout...
273 if (OutputFilename != "-") {
274 if (!Force && std::ifstream(OutputFilename.c_str())) {
275 // If force is not specified, make sure not to overwrite a file!
276 cerr << argv[0] << ": error opening '" << OutputFilename
277 << "': file exists!\n"
278 << "Use -f command line argument to force output\n";
281 std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
283 Out = new std::ofstream(OutputFilename.c_str(), io_mode);
286 cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
290 // Make sure that the Output file gets unlinked from the disk if we get a
292 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
295 // If the output is set to be emitted to standard out, and standard out is a
296 // console, print out a warning message and refuse to do it. We don't
297 // impress anyone by spewing tons of binary goo to a terminal.
298 if (!Force && !NoOutput && CheckBytecodeOutputToConsole(Out,!Quiet)) {
302 // Create a PassManager to hold and optimize the collection of passes we are
307 // Add an appropriate TargetData instance for this module...
308 Passes.add(new TargetData(M.get()));
310 // If -std-compile-opts is given, add in all the standard compilation
311 // optimizations first. This will handle -strip-debug, -disable-inline,
312 // and -disable-opt as well.
313 if (StandardCompileOpts)
314 AddStandardCompilePasses(Passes);
316 // otherwise if the -strip-debug command line option was specified, add it.
318 addPass(Passes, createStripSymbolsPass(true));
320 // Create a new optimization pass for each one specified on the command line
321 for (unsigned i = 0; i < PassList.size(); ++i) {
322 const PassInfo *PassInf = PassList[i];
324 if (PassInf->getNormalCtor())
325 P = PassInf->getNormalCtor()();
327 cerr << argv[0] << ": cannot create pass: "
328 << PassInf->getPassName() << "\n";
333 if (dynamic_cast<BasicBlockPass*>(P))
334 Passes.add(new BasicBlockPassPrinter(PassInf));
335 else if (dynamic_cast<FunctionPass*>(P))
336 Passes.add(new FunctionPassPrinter(PassInf));
338 Passes.add(new ModulePassPrinter(PassInf));
343 Passes.add(new PrintModulePass(&cerr));
346 // Check that the module is well formed on completion of optimization
347 if (!NoVerify && !VerifyEach)
348 Passes.add(createVerifierPass());
350 // Write bytecode out to disk or cout as the last step...
352 if (!NoOutput && !AnalyzeOnly)
353 Passes.add(new WriteBytecodePass(&L, false, !NoCompress));
355 // Now that we have all of the passes ready, run them.
356 Passes.run(*M.get());
360 } catch (const std::string& msg) {
361 cerr << argv[0] << ": " << msg << "\n";
363 cerr << argv[0] << ": Unexpected unknown exception occurred.\n";