1 //===- PassManagerBuilder.cpp - Build Standard Pass -----------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file defines the PassManagerBuilder class, which is used to set up a 11 // "standard" optimization sequence suitable for languages like C and C++. 12 // 13 //===----------------------------------------------------------------------===// 14 15 16 #include "llvm/Transforms/IPO/PassManagerBuilder.h" 17 18 #include "llvm-c/Transforms/PassManagerBuilder.h" 19 20 #include "llvm/PassManager.h" 21 #include "llvm/DefaultPasses.h" 22 #include "llvm/PassManager.h" 23 #include "llvm/Analysis/Passes.h" 24 #include "llvm/Analysis/Verifier.h" 25 #include "llvm/Target/TargetLibraryInfo.h" 26 #include "llvm/Transforms/Scalar.h" 27 #include "llvm/Transforms/IPO.h" 28 #include "llvm/ADT/SmallVector.h" 29 #include "llvm/Support/ManagedStatic.h" 30 31 using namespace llvm; 32 33 PassManagerBuilder::PassManagerBuilder() { 34 OptLevel = 2; 35 SizeLevel = 0; 36 LibraryInfo = 0; 37 Inliner = 0; 38 DisableSimplifyLibCalls = false; 39 DisableUnitAtATime = false; 40 DisableUnrollLoops = false; 41 } 42 43 PassManagerBuilder::~PassManagerBuilder() { 44 delete LibraryInfo; 45 delete Inliner; 46 } 47 48 /// Set of global extensions, automatically added as part of the standard set. 49 static ManagedStatic<SmallVector<std::pair<PassManagerBuilder::ExtensionPointTy, 50 PassManagerBuilder::ExtensionFn>, 8> > GlobalExtensions; 51 52 void PassManagerBuilder::addGlobalExtension( 53 PassManagerBuilder::ExtensionPointTy Ty, 54 PassManagerBuilder::ExtensionFn Fn) { 55 GlobalExtensions->push_back(std::make_pair(Ty, Fn)); 56 } 57 58 void PassManagerBuilder::addExtension(ExtensionPointTy Ty, ExtensionFn Fn) { 59 Extensions.push_back(std::make_pair(Ty, Fn)); 60 } 61 62 void PassManagerBuilder::addExtensionsToPM(ExtensionPointTy ETy, 63 PassManagerBase &PM) const { 64 for (unsigned i = 0, e = GlobalExtensions->size(); i != e; ++i) 65 if ((*GlobalExtensions)[i].first == ETy) 66 (*GlobalExtensions)[i].second(*this, PM); 67 for (unsigned i = 0, e = Extensions.size(); i != e; ++i) 68 if (Extensions[i].first == ETy) 69 Extensions[i].second(*this, PM); 70 } 71 72 void 73 PassManagerBuilder::addInitialAliasAnalysisPasses(PassManagerBase &PM) const { 74 // Add TypeBasedAliasAnalysis before BasicAliasAnalysis so that 75 // BasicAliasAnalysis wins if they disagree. This is intended to help 76 // support "obvious" type-punning idioms. 77 PM.add(createTypeBasedAliasAnalysisPass()); 78 PM.add(createBasicAliasAnalysisPass()); 79 } 80 81 void PassManagerBuilder::populateFunctionPassManager(FunctionPassManager &FPM) { 82 addExtensionsToPM(EP_EarlyAsPossible, FPM); 83 84 // Add LibraryInfo if we have some. 85 if (LibraryInfo) FPM.add(new TargetLibraryInfo(*LibraryInfo)); 86 87 if (OptLevel == 0) return; 88 89 addInitialAliasAnalysisPasses(FPM); 90 91 FPM.add(createCFGSimplificationPass()); 92 FPM.add(createScalarReplAggregatesPass()); 93 FPM.add(createEarlyCSEPass()); 94 FPM.add(createLowerExpectIntrinsicPass()); 95 } 96 97 void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) { 98 // If all optimizations are disabled, just run the always-inline pass. 99 if (OptLevel == 0) { 100 if (Inliner) { 101 MPM.add(Inliner); 102 Inliner = 0; 103 } 104 return; 105 } 106 107 // Add LibraryInfo if we have some. 108 if (LibraryInfo) MPM.add(new TargetLibraryInfo(*LibraryInfo)); 109 110 addInitialAliasAnalysisPasses(MPM); 111 112 if (!DisableUnitAtATime) { 113 MPM.add(createGlobalOptimizerPass()); // Optimize out global vars 114 115 MPM.add(createIPSCCPPass()); // IP SCCP 116 MPM.add(createDeadArgEliminationPass()); // Dead argument elimination 117 118 MPM.add(createInstructionCombiningPass());// Clean up after IPCP & DAE 119 MPM.add(createCFGSimplificationPass()); // Clean up after IPCP & DAE 120 } 121 122 // Start of CallGraph SCC passes. 123 if (!DisableUnitAtATime) 124 MPM.add(createPruneEHPass()); // Remove dead EH info 125 if (Inliner) { 126 MPM.add(Inliner); 127 Inliner = 0; 128 } 129 if (!DisableUnitAtATime) 130 MPM.add(createFunctionAttrsPass()); // Set readonly/readnone attrs 131 if (OptLevel > 2) 132 MPM.add(createArgumentPromotionPass()); // Scalarize uninlined fn args 133 134 // Start of function pass. 135 // Break up aggregate allocas, using SSAUpdater. 136 MPM.add(createScalarReplAggregatesPass(-1, false)); 137 MPM.add(createEarlyCSEPass()); // Catch trivial redundancies 138 if (!DisableSimplifyLibCalls) 139 MPM.add(createSimplifyLibCallsPass()); // Library Call Optimizations 140 MPM.add(createJumpThreadingPass()); // Thread jumps. 141 MPM.add(createCorrelatedValuePropagationPass()); // Propagate conditionals 142 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs 143 MPM.add(createInstructionCombiningPass()); // Combine silly seq's 144 145 MPM.add(createTailCallEliminationPass()); // Eliminate tail calls 146 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs 147 MPM.add(createReassociatePass()); // Reassociate expressions 148 MPM.add(createLoopRotatePass()); // Rotate Loop 149 MPM.add(createLICMPass()); // Hoist loop invariants 150 MPM.add(createLoopUnswitchPass(SizeLevel || OptLevel < 3)); 151 MPM.add(createInstructionCombiningPass()); 152 MPM.add(createIndVarSimplifyPass()); // Canonicalize indvars 153 MPM.add(createLoopIdiomPass()); // Recognize idioms like memset. 154 MPM.add(createLoopDeletionPass()); // Delete dead loops 155 if (!DisableUnrollLoops) 156 MPM.add(createLoopUnrollPass()); // Unroll small loops 157 addExtensionsToPM(EP_LoopOptimizerEnd, MPM); 158 159 if (OptLevel > 1) 160 MPM.add(createGVNPass()); // Remove redundancies 161 MPM.add(createMemCpyOptPass()); // Remove memcpy / form memset 162 MPM.add(createSCCPPass()); // Constant prop with SCCP 163 164 // Run instcombine after redundancy elimination to exploit opportunities 165 // opened up by them. 166 MPM.add(createInstructionCombiningPass()); 167 MPM.add(createJumpThreadingPass()); // Thread jumps 168 MPM.add(createCorrelatedValuePropagationPass()); 169 MPM.add(createDeadStoreEliminationPass()); // Delete dead stores 170 171 addExtensionsToPM(EP_ScalarOptimizerLate, MPM); 172 173 MPM.add(createAggressiveDCEPass()); // Delete dead instructions 174 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs 175 MPM.add(createInstructionCombiningPass()); // Clean up after everything. 176 177 if (!DisableUnitAtATime) { 178 // FIXME: We shouldn't bother with this anymore. 179 MPM.add(createStripDeadPrototypesPass()); // Get rid of dead prototypes 180 181 // GlobalOpt already deletes dead functions and globals, at -O3 try a 182 // late pass of GlobalDCE. It is capable of deleting dead cycles. 183 if (OptLevel > 2) 184 MPM.add(createGlobalDCEPass()); // Remove dead fns and globals. 185 186 if (OptLevel > 1) 187 MPM.add(createConstantMergePass()); // Merge dup global constants 188 } 189 } 190 191 void PassManagerBuilder::populateLTOPassManager(PassManagerBase &PM, 192 bool Internalize, 193 bool RunInliner) { 194 // Provide AliasAnalysis services for optimizations. 195 addInitialAliasAnalysisPasses(PM); 196 197 // Now that composite has been compiled, scan through the module, looking 198 // for a main function. If main is defined, mark all other functions 199 // internal. 200 if (Internalize) 201 PM.add(createInternalizePass(true)); 202 203 // Propagate constants at call sites into the functions they call. This 204 // opens opportunities for globalopt (and inlining) by substituting function 205 // pointers passed as arguments to direct uses of functions. 206 PM.add(createIPSCCPPass()); 207 208 // Now that we internalized some globals, see if we can hack on them! 209 PM.add(createGlobalOptimizerPass()); 210 211 // Linking modules together can lead to duplicated global constants, only 212 // keep one copy of each constant. 213 PM.add(createConstantMergePass()); 214 215 // Remove unused arguments from functions. 216 PM.add(createDeadArgEliminationPass()); 217 218 // Reduce the code after globalopt and ipsccp. Both can open up significant 219 // simplification opportunities, and both can propagate functions through 220 // function pointers. When this happens, we often have to resolve varargs 221 // calls, etc, so let instcombine do this. 222 PM.add(createInstructionCombiningPass()); 223 224 // Inline small functions 225 if (RunInliner) 226 PM.add(createFunctionInliningPass()); 227 228 PM.add(createPruneEHPass()); // Remove dead EH info. 229 230 // Optimize globals again if we ran the inliner. 231 if (RunInliner) 232 PM.add(createGlobalOptimizerPass()); 233 PM.add(createGlobalDCEPass()); // Remove dead functions. 234 235 // If we didn't decide to inline a function, check to see if we can 236 // transform it to pass arguments by value instead of by reference. 237 PM.add(createArgumentPromotionPass()); 238 239 // The IPO passes may leave cruft around. Clean up after them. 240 PM.add(createInstructionCombiningPass()); 241 PM.add(createJumpThreadingPass()); 242 // Break up allocas 243 PM.add(createScalarReplAggregatesPass()); 244 245 // Run a few AA driven optimizations here and now, to cleanup the code. 246 PM.add(createFunctionAttrsPass()); // Add nocapture. 247 PM.add(createGlobalsModRefPass()); // IP alias analysis. 248 249 PM.add(createLICMPass()); // Hoist loop invariants. 250 PM.add(createGVNPass()); // Remove redundancies. 251 PM.add(createMemCpyOptPass()); // Remove dead memcpys. 252 // Nuke dead stores. 253 PM.add(createDeadStoreEliminationPass()); 254 255 // Cleanup and simplify the code after the scalar optimizations. 256 PM.add(createInstructionCombiningPass()); 257 258 PM.add(createJumpThreadingPass()); 259 260 // Delete basic blocks, which optimization passes may have killed. 261 PM.add(createCFGSimplificationPass()); 262 263 // Now that we have optimized the program, discard unreachable functions. 264 PM.add(createGlobalDCEPass()); 265 } 266 267 LLVMPassManagerBuilderRef LLVMPassManagerBuilderCreate(void) { 268 PassManagerBuilder *PMB = new PassManagerBuilder(); 269 return wrap(PMB); 270 } 271 272 void LLVMPassManagerBuilderDispose(LLVMPassManagerBuilderRef PMB) { 273 PassManagerBuilder *Builder = unwrap(PMB); 274 delete Builder; 275 } 276 277 void 278 LLVMPassManagerBuilderSetOptLevel(LLVMPassManagerBuilderRef PMB, 279 unsigned OptLevel) { 280 PassManagerBuilder *Builder = unwrap(PMB); 281 Builder->OptLevel = OptLevel; 282 } 283 284 void 285 LLVMPassManagerBuilderSetSizeLevel(LLVMPassManagerBuilderRef PMB, 286 unsigned SizeLevel) { 287 PassManagerBuilder *Builder = unwrap(PMB); 288 Builder->SizeLevel = SizeLevel; 289 } 290 291 void 292 LLVMPassManagerBuilderSetDisableUnitAtATime(LLVMPassManagerBuilderRef PMB, 293 LLVMBool Value) { 294 PassManagerBuilder *Builder = unwrap(PMB); 295 Builder->DisableUnitAtATime = Value; 296 } 297 298 void 299 LLVMPassManagerBuilderSetDisableUnrollLoops(LLVMPassManagerBuilderRef PMB, 300 LLVMBool Value) { 301 PassManagerBuilder *Builder = unwrap(PMB); 302 Builder->DisableUnrollLoops = Value; 303 } 304 305 void 306 LLVMPassManagerBuilderSetDisableSimplifyLibCalls(LLVMPassManagerBuilderRef PMB, 307 LLVMBool Value) { 308 PassManagerBuilder *Builder = unwrap(PMB); 309 Builder->DisableSimplifyLibCalls = Value; 310 } 311 312 void 313 LLVMPassManagerBuilderUseInlinerWithThreshold(LLVMPassManagerBuilderRef PMB, 314 unsigned Threshold) { 315 PassManagerBuilder *Builder = unwrap(PMB); 316 Builder->Inliner = createFunctionInliningPass(Threshold); 317 } 318 319 void 320 LLVMPassManagerBuilderPopulateFunctionPassManager(LLVMPassManagerBuilderRef PMB, 321 LLVMPassManagerRef PM) { 322 PassManagerBuilder *Builder = unwrap(PMB); 323 FunctionPassManager *FPM = unwrap<FunctionPassManager>(PM); 324 Builder->populateFunctionPassManager(*FPM); 325 } 326 327 void 328 LLVMPassManagerBuilderPopulateModulePassManager(LLVMPassManagerBuilderRef PMB, 329 LLVMPassManagerRef PM) { 330 PassManagerBuilder *Builder = unwrap(PMB); 331 PassManagerBase *MPM = unwrap(PM); 332 Builder->populateModulePassManager(*MPM); 333 } 334 335 void LLVMPassManagerBuilderPopulateLTOPassManager(LLVMPassManagerBuilderRef PMB, 336 LLVMPassManagerRef PM, 337 bool Internalize, 338 bool RunInliner) { 339 PassManagerBuilder *Builder = unwrap(PMB); 340 PassManagerBase *LPM = unwrap(PM); 341 Builder->populateLTOPassManager(*LPM, Internalize, RunInliner); 342 } 343 344