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 {
102 const PassInfo *PassToPrint;
103 ModulePassPrinter(const PassInfo *PI) : ModulePass((intptr_t)&ID),
106 virtual bool runOnModule(Module &M) {
108 cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
109 getAnalysisID<Pass>(PassToPrint).print(cout, &M);
112 // Get and print pass...
116 virtual const char *getPassName() const { return "'Pass' Printer"; }
118 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
119 AU.addRequiredID(PassToPrint);
120 AU.setPreservesAll();
124 char ModulePassPrinter::ID = 0;
125 struct FunctionPassPrinter : public FunctionPass {
126 const PassInfo *PassToPrint;
128 FunctionPassPrinter(const PassInfo *PI) : FunctionPass((intptr_t)&ID),
131 virtual bool runOnFunction(Function &F) {
133 cout << "Printing analysis '" << PassToPrint->getPassName()
134 << "' for function '" << F.getName() << "':\n";
136 // Get and print pass...
137 getAnalysisID<Pass>(PassToPrint).print(cout, F.getParent());
141 virtual const char *getPassName() const { return "FunctionPass Printer"; }
143 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
144 AU.addRequiredID(PassToPrint);
145 AU.setPreservesAll();
149 char FunctionPassPrinter::ID = 0;
150 struct BasicBlockPassPrinter : public BasicBlockPass {
151 const PassInfo *PassToPrint;
153 BasicBlockPassPrinter(const PassInfo *PI)
154 : BasicBlockPass((intptr_t)&ID), PassToPrint(PI) {}
156 virtual bool runOnBasicBlock(BasicBlock &BB) {
158 cout << "Printing Analysis info for BasicBlock '" << BB.getName()
159 << "': Pass " << PassToPrint->getPassName() << ":\n";
162 // Get and print pass...
163 getAnalysisID<Pass>(PassToPrint).print(cout, BB.getParent()->getParent());
167 virtual const char *getPassName() const { return "BasicBlockPass Printer"; }
169 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
170 AU.addRequiredID(PassToPrint);
171 AU.setPreservesAll();
175 char BasicBlockPassPrinter::ID = 0;
176 inline void addPass(PassManager &PM, Pass *P) {
177 // Add the pass to the pass manager...
180 // If we are verifying all of the intermediate steps, add the verifier...
181 if (VerifyEach) PM.add(createVerifierPass());
184 void AddStandardCompilePasses(PassManager &PM) {
185 PM.add(createVerifierPass()); // Verify that input is correct
187 addPass(PM, createLowerSetJmpPass()); // Lower llvm.setjmp/.longjmp
189 // If the -strip-debug command line option was specified, do it.
191 addPass(PM, createStripSymbolsPass(true));
193 if (DisableOptimizations) return;
195 addPass(PM, createRaiseAllocationsPass()); // call %malloc -> malloc inst
196 addPass(PM, createCFGSimplificationPass()); // Clean up disgusting code
197 addPass(PM, createPromoteMemoryToRegisterPass());// Kill useless allocas
198 addPass(PM, createGlobalOptimizerPass()); // Optimize out global vars
199 addPass(PM, createGlobalDCEPass()); // Remove unused fns and globs
200 addPass(PM, createIPConstantPropagationPass());// IP Constant Propagation
201 addPass(PM, createDeadArgEliminationPass()); // Dead argument elimination
202 addPass(PM, createInstructionCombiningPass()); // Clean up after IPCP & DAE
203 addPass(PM, createCFGSimplificationPass()); // Clean up after IPCP & DAE
205 addPass(PM, createPruneEHPass()); // Remove dead EH info
208 addPass(PM, createFunctionInliningPass()); // Inline small functions
209 addPass(PM, createArgumentPromotionPass()); // Scalarize uninlined fn args
211 addPass(PM, createTailDuplicationPass()); // Simplify cfg by copying code
212 addPass(PM, createInstructionCombiningPass()); // Cleanup for scalarrepl.
213 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
214 addPass(PM, createScalarReplAggregatesPass()); // Break up aggregate allocas
215 addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
216 addPass(PM, createCondPropagationPass()); // Propagate conditionals
218 addPass(PM, createTailCallEliminationPass()); // Eliminate tail calls
219 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
220 addPass(PM, createReassociatePass()); // Reassociate expressions
221 addPass(PM, createLoopRotatePass());
222 addPass(PM, createLICMPass()); // Hoist loop invariants
223 addPass(PM, createLoopUnswitchPass()); // Unswitch loops.
224 addPass(PM, createInstructionCombiningPass()); // Clean up after LICM/reassoc
225 addPass(PM, createIndVarSimplifyPass()); // Canonicalize indvars
226 addPass(PM, createLoopUnrollPass()); // Unroll small loops
227 addPass(PM, createInstructionCombiningPass()); // Clean up after the unroller
228 addPass(PM, createLoadValueNumberingPass()); // GVN for load instructions
229 addPass(PM, createGCSEPass()); // Remove common subexprs
230 addPass(PM, createSCCPPass()); // Constant prop with SCCP
232 // Run instcombine after redundancy elimination to exploit opportunities
233 // opened up by them.
234 addPass(PM, createInstructionCombiningPass());
235 addPass(PM, createCondPropagationPass()); // Propagate conditionals
237 addPass(PM, createDeadStoreEliminationPass()); // Delete dead stores
238 addPass(PM, createAggressiveDCEPass()); // SSA based 'Aggressive DCE'
239 addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
240 addPass(PM, createSimplifyLibCallsPass()); // Library Call Optimizations
241 addPass(PM, createDeadTypeEliminationPass()); // Eliminate dead types
242 addPass(PM, createConstantMergePass()); // Merge dup global constants
245 } // anonymous namespace
248 //===----------------------------------------------------------------------===//
251 int main(int argc, char **argv) {
252 llvm_shutdown_obj X; // Call llvm_shutdown() on exit.
254 cl::ParseCommandLineOptions(argc, argv,
255 " llvm .bc -> .bc modular optimizer and analysis printer \n");
256 sys::PrintStackTraceOnErrorSignal();
258 // Allocate a full target machine description only if necessary.
259 // FIXME: The choice of target should be controllable on the command line.
260 std::auto_ptr<TargetMachine> target;
262 std::string ErrorMessage;
264 // Load the input module...
265 std::auto_ptr<Module> M(ParseBytecodeFile(InputFilename,
266 Compressor::decompressToNewBuffer, &ErrorMessage));
268 cerr << argv[0] << ": ";
269 if (ErrorMessage.size())
270 cerr << ErrorMessage << "\n";
272 cerr << "bytecode didn't read correctly.\n";
276 // Figure out what stream we are supposed to write to...
277 // FIXME: cout is not binary!
278 std::ostream *Out = &std::cout; // Default to printing to stdout...
279 if (OutputFilename != "-") {
280 if (!Force && std::ifstream(OutputFilename.c_str())) {
281 // If force is not specified, make sure not to overwrite a file!
282 cerr << argv[0] << ": error opening '" << OutputFilename
283 << "': file exists!\n"
284 << "Use -f command line argument to force output\n";
287 std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
289 Out = new std::ofstream(OutputFilename.c_str(), io_mode);
292 cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
296 // Make sure that the Output file gets unlinked from the disk if we get a
298 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
301 // If the output is set to be emitted to standard out, and standard out is a
302 // console, print out a warning message and refuse to do it. We don't
303 // impress anyone by spewing tons of binary goo to a terminal.
304 if (!Force && !NoOutput && CheckBytecodeOutputToConsole(Out,!Quiet)) {
308 // Create a PassManager to hold and optimize the collection of passes we are
313 // Add an appropriate TargetData instance for this module...
314 Passes.add(new TargetData(M.get()));
316 // If -std-compile-opts is given, add in all the standard compilation
317 // optimizations first. This will handle -strip-debug, -disable-inline,
318 // and -disable-opt as well.
319 if (StandardCompileOpts)
320 AddStandardCompilePasses(Passes);
322 // otherwise if the -strip-debug command line option was specified, add it.
324 addPass(Passes, createStripSymbolsPass(true));
326 // Create a new optimization pass for each one specified on the command line
327 for (unsigned i = 0; i < PassList.size(); ++i) {
328 const PassInfo *PassInf = PassList[i];
330 if (PassInf->getNormalCtor())
331 P = PassInf->getNormalCtor()();
333 cerr << argv[0] << ": cannot create pass: "
334 << PassInf->getPassName() << "\n";
339 if (dynamic_cast<BasicBlockPass*>(P))
340 Passes.add(new BasicBlockPassPrinter(PassInf));
341 else if (dynamic_cast<FunctionPass*>(P))
342 Passes.add(new FunctionPassPrinter(PassInf));
344 Passes.add(new ModulePassPrinter(PassInf));
349 Passes.add(new PrintModulePass(&cerr));
352 // Check that the module is well formed on completion of optimization
353 if (!NoVerify && !VerifyEach)
354 Passes.add(createVerifierPass());
356 // Write bytecode out to disk or cout as the last step...
358 if (!NoOutput && !AnalyzeOnly)
359 Passes.add(new WriteBytecodePass(&L, false, !NoCompress));
361 // Now that we have all of the passes ready, run them.
362 Passes.run(*M.get());
366 } catch (const std::string& msg) {
367 cerr << argv[0] << ": " << msg << "\n";
369 cerr << argv[0] << ": Unexpected unknown exception occurred.\n";