Inliner.cpp revision 034b94b17006f51722886b0f2283fb6fb19aca1f
1//===- Inliner.cpp - Code common to all inliners --------------------------===// 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 implements the mechanics required to implement inlining without 11// missing any calls and updating the call graph. The decisions of which calls 12// are profitable to inline are implemented elsewhere. 13// 14//===----------------------------------------------------------------------===// 15 16#define DEBUG_TYPE "inline" 17#include "llvm/Transforms/IPO/InlinerPass.h" 18#include "llvm/ADT/SmallPtrSet.h" 19#include "llvm/ADT/Statistic.h" 20#include "llvm/Analysis/CallGraph.h" 21#include "llvm/Analysis/InlineCost.h" 22#include "llvm/DataLayout.h" 23#include "llvm/Instructions.h" 24#include "llvm/IntrinsicInst.h" 25#include "llvm/Module.h" 26#include "llvm/Support/CallSite.h" 27#include "llvm/Support/CommandLine.h" 28#include "llvm/Support/Debug.h" 29#include "llvm/Support/raw_ostream.h" 30#include "llvm/Target/TargetLibraryInfo.h" 31#include "llvm/Transforms/Utils/Cloning.h" 32#include "llvm/Transforms/Utils/Local.h" 33using namespace llvm; 34 35STATISTIC(NumInlined, "Number of functions inlined"); 36STATISTIC(NumCallsDeleted, "Number of call sites deleted, not inlined"); 37STATISTIC(NumDeleted, "Number of functions deleted because all callers found"); 38STATISTIC(NumMergedAllocas, "Number of allocas merged together"); 39 40// This weirdly named statistic tracks the number of times that, when attempting 41// to inline a function A into B, we analyze the callers of B in order to see 42// if those would be more profitable and blocked inline steps. 43STATISTIC(NumCallerCallersAnalyzed, "Number of caller-callers analyzed"); 44 45static cl::opt<int> 46InlineLimit("inline-threshold", cl::Hidden, cl::init(225), cl::ZeroOrMore, 47 cl::desc("Control the amount of inlining to perform (default = 225)")); 48 49static cl::opt<int> 50HintThreshold("inlinehint-threshold", cl::Hidden, cl::init(325), 51 cl::desc("Threshold for inlining functions with inline hint")); 52 53// Threshold to use when optsize is specified (and there is no -inline-limit). 54const int OptSizeThreshold = 75; 55 56Inliner::Inliner(char &ID) 57 : CallGraphSCCPass(ID), InlineThreshold(InlineLimit), InsertLifetime(true) {} 58 59Inliner::Inliner(char &ID, int Threshold, bool InsertLifetime) 60 : CallGraphSCCPass(ID), InlineThreshold(InlineLimit.getNumOccurrences() > 0 ? 61 InlineLimit : Threshold), 62 InsertLifetime(InsertLifetime) {} 63 64/// getAnalysisUsage - For this class, we declare that we require and preserve 65/// the call graph. If the derived class implements this method, it should 66/// always explicitly call the implementation here. 67void Inliner::getAnalysisUsage(AnalysisUsage &Info) const { 68 CallGraphSCCPass::getAnalysisUsage(Info); 69} 70 71 72typedef DenseMap<ArrayType*, std::vector<AllocaInst*> > 73InlinedArrayAllocasTy; 74 75/// InlineCallIfPossible - If it is possible to inline the specified call site, 76/// do so and update the CallGraph for this operation. 77/// 78/// This function also does some basic book-keeping to update the IR. The 79/// InlinedArrayAllocas map keeps track of any allocas that are already 80/// available from other functions inlined into the caller. If we are able to 81/// inline this call site we attempt to reuse already available allocas or add 82/// any new allocas to the set if not possible. 83static bool InlineCallIfPossible(CallSite CS, InlineFunctionInfo &IFI, 84 InlinedArrayAllocasTy &InlinedArrayAllocas, 85 int InlineHistory, bool InsertLifetime) { 86 Function *Callee = CS.getCalledFunction(); 87 Function *Caller = CS.getCaller(); 88 89 // Try to inline the function. Get the list of static allocas that were 90 // inlined. 91 if (!InlineFunction(CS, IFI, InsertLifetime)) 92 return false; 93 94 // If the inlined function had a higher stack protection level than the 95 // calling function, then bump up the caller's stack protection level. 96 if (Callee->getFnAttributes().hasAttribute(Attribute::StackProtectReq)) 97 Caller->addFnAttr(Attribute::StackProtectReq); 98 else if (Callee->getFnAttributes().hasAttribute(Attribute::StackProtect) && 99 !Caller->getFnAttributes().hasAttribute(Attribute::StackProtectReq)) 100 Caller->addFnAttr(Attribute::StackProtect); 101 102 // Look at all of the allocas that we inlined through this call site. If we 103 // have already inlined other allocas through other calls into this function, 104 // then we know that they have disjoint lifetimes and that we can merge them. 105 // 106 // There are many heuristics possible for merging these allocas, and the 107 // different options have different tradeoffs. One thing that we *really* 108 // don't want to hurt is SRoA: once inlining happens, often allocas are no 109 // longer address taken and so they can be promoted. 110 // 111 // Our "solution" for that is to only merge allocas whose outermost type is an 112 // array type. These are usually not promoted because someone is using a 113 // variable index into them. These are also often the most important ones to 114 // merge. 115 // 116 // A better solution would be to have real memory lifetime markers in the IR 117 // and not have the inliner do any merging of allocas at all. This would 118 // allow the backend to do proper stack slot coloring of all allocas that 119 // *actually make it to the backend*, which is really what we want. 120 // 121 // Because we don't have this information, we do this simple and useful hack. 122 // 123 SmallPtrSet<AllocaInst*, 16> UsedAllocas; 124 125 // When processing our SCC, check to see if CS was inlined from some other 126 // call site. For example, if we're processing "A" in this code: 127 // A() { B() } 128 // B() { x = alloca ... C() } 129 // C() { y = alloca ... } 130 // Assume that C was not inlined into B initially, and so we're processing A 131 // and decide to inline B into A. Doing this makes an alloca available for 132 // reuse and makes a callsite (C) available for inlining. When we process 133 // the C call site we don't want to do any alloca merging between X and Y 134 // because their scopes are not disjoint. We could make this smarter by 135 // keeping track of the inline history for each alloca in the 136 // InlinedArrayAllocas but this isn't likely to be a significant win. 137 if (InlineHistory != -1) // Only do merging for top-level call sites in SCC. 138 return true; 139 140 // Loop over all the allocas we have so far and see if they can be merged with 141 // a previously inlined alloca. If not, remember that we had it. 142 for (unsigned AllocaNo = 0, e = IFI.StaticAllocas.size(); 143 AllocaNo != e; ++AllocaNo) { 144 AllocaInst *AI = IFI.StaticAllocas[AllocaNo]; 145 146 // Don't bother trying to merge array allocations (they will usually be 147 // canonicalized to be an allocation *of* an array), or allocations whose 148 // type is not itself an array (because we're afraid of pessimizing SRoA). 149 ArrayType *ATy = dyn_cast<ArrayType>(AI->getAllocatedType()); 150 if (ATy == 0 || AI->isArrayAllocation()) 151 continue; 152 153 // Get the list of all available allocas for this array type. 154 std::vector<AllocaInst*> &AllocasForType = InlinedArrayAllocas[ATy]; 155 156 // Loop over the allocas in AllocasForType to see if we can reuse one. Note 157 // that we have to be careful not to reuse the same "available" alloca for 158 // multiple different allocas that we just inlined, we use the 'UsedAllocas' 159 // set to keep track of which "available" allocas are being used by this 160 // function. Also, AllocasForType can be empty of course! 161 bool MergedAwayAlloca = false; 162 for (unsigned i = 0, e = AllocasForType.size(); i != e; ++i) { 163 AllocaInst *AvailableAlloca = AllocasForType[i]; 164 165 // The available alloca has to be in the right function, not in some other 166 // function in this SCC. 167 if (AvailableAlloca->getParent() != AI->getParent()) 168 continue; 169 170 // If the inlined function already uses this alloca then we can't reuse 171 // it. 172 if (!UsedAllocas.insert(AvailableAlloca)) 173 continue; 174 175 // Otherwise, we *can* reuse it, RAUW AI into AvailableAlloca and declare 176 // success! 177 DEBUG(dbgs() << " ***MERGED ALLOCA: " << *AI << "\n\t\tINTO: " 178 << *AvailableAlloca << '\n'); 179 180 AI->replaceAllUsesWith(AvailableAlloca); 181 AI->eraseFromParent(); 182 MergedAwayAlloca = true; 183 ++NumMergedAllocas; 184 IFI.StaticAllocas[AllocaNo] = 0; 185 break; 186 } 187 188 // If we already nuked the alloca, we're done with it. 189 if (MergedAwayAlloca) 190 continue; 191 192 // If we were unable to merge away the alloca either because there are no 193 // allocas of the right type available or because we reused them all 194 // already, remember that this alloca came from an inlined function and mark 195 // it used so we don't reuse it for other allocas from this inline 196 // operation. 197 AllocasForType.push_back(AI); 198 UsedAllocas.insert(AI); 199 } 200 201 return true; 202} 203 204unsigned Inliner::getInlineThreshold(CallSite CS) const { 205 int thres = InlineThreshold; // -inline-threshold or else selected by 206 // overall opt level 207 208 // If -inline-threshold is not given, listen to the optsize attribute when it 209 // would decrease the threshold. 210 Function *Caller = CS.getCaller(); 211 bool OptSize = Caller && !Caller->isDeclaration() && 212 Caller->getFnAttributes().hasAttribute(Attribute::OptimizeForSize); 213 if (!(InlineLimit.getNumOccurrences() > 0) && OptSize && 214 OptSizeThreshold < thres) 215 thres = OptSizeThreshold; 216 217 // Listen to the inlinehint attribute when it would increase the threshold 218 // and the caller does not need to minimize its size. 219 Function *Callee = CS.getCalledFunction(); 220 bool InlineHint = Callee && !Callee->isDeclaration() && 221 Callee->getFnAttributes().hasAttribute(Attribute::InlineHint); 222 if (InlineHint && HintThreshold > thres 223 && !Caller->getFnAttributes().hasAttribute(Attribute::MinSize)) 224 thres = HintThreshold; 225 226 return thres; 227} 228 229/// shouldInline - Return true if the inliner should attempt to inline 230/// at the given CallSite. 231bool Inliner::shouldInline(CallSite CS) { 232 InlineCost IC = getInlineCost(CS); 233 234 if (IC.isAlways()) { 235 DEBUG(dbgs() << " Inlining: cost=always" 236 << ", Call: " << *CS.getInstruction() << "\n"); 237 return true; 238 } 239 240 if (IC.isNever()) { 241 DEBUG(dbgs() << " NOT Inlining: cost=never" 242 << ", Call: " << *CS.getInstruction() << "\n"); 243 return false; 244 } 245 246 Function *Caller = CS.getCaller(); 247 if (!IC) { 248 DEBUG(dbgs() << " NOT Inlining: cost=" << IC.getCost() 249 << ", thres=" << (IC.getCostDelta() + IC.getCost()) 250 << ", Call: " << *CS.getInstruction() << "\n"); 251 return false; 252 } 253 254 // Try to detect the case where the current inlining candidate caller (call 255 // it B) is a static or linkonce-ODR function and is an inlining candidate 256 // elsewhere, and the current candidate callee (call it C) is large enough 257 // that inlining it into B would make B too big to inline later. In these 258 // circumstances it may be best not to inline C into B, but to inline B into 259 // its callers. 260 // 261 // This only applies to static and linkonce-ODR functions because those are 262 // expected to be available for inlining in the translation units where they 263 // are used. Thus we will always have the opportunity to make local inlining 264 // decisions. Importantly the linkonce-ODR linkage covers inline functions 265 // and templates in C++. 266 // 267 // FIXME: All of this logic should be sunk into getInlineCost. It relies on 268 // the internal implementation of the inline cost metrics rather than 269 // treating them as truly abstract units etc. 270 if (Caller->hasLocalLinkage() || 271 Caller->getLinkage() == GlobalValue::LinkOnceODRLinkage) { 272 int TotalSecondaryCost = 0; 273 // The candidate cost to be imposed upon the current function. 274 int CandidateCost = IC.getCost() - (InlineConstants::CallPenalty + 1); 275 // This bool tracks what happens if we do NOT inline C into B. 276 bool callerWillBeRemoved = Caller->hasLocalLinkage(); 277 // This bool tracks what happens if we DO inline C into B. 278 bool inliningPreventsSomeOuterInline = false; 279 for (Value::use_iterator I = Caller->use_begin(), E =Caller->use_end(); 280 I != E; ++I) { 281 CallSite CS2(*I); 282 283 // If this isn't a call to Caller (it could be some other sort 284 // of reference) skip it. Such references will prevent the caller 285 // from being removed. 286 if (!CS2 || CS2.getCalledFunction() != Caller) { 287 callerWillBeRemoved = false; 288 continue; 289 } 290 291 InlineCost IC2 = getInlineCost(CS2); 292 ++NumCallerCallersAnalyzed; 293 if (!IC2) { 294 callerWillBeRemoved = false; 295 continue; 296 } 297 if (IC2.isAlways()) 298 continue; 299 300 // See if inlining or original callsite would erase the cost delta of 301 // this callsite. We subtract off the penalty for the call instruction, 302 // which we would be deleting. 303 if (IC2.getCostDelta() <= CandidateCost) { 304 inliningPreventsSomeOuterInline = true; 305 TotalSecondaryCost += IC2.getCost(); 306 } 307 } 308 // If all outer calls to Caller would get inlined, the cost for the last 309 // one is set very low by getInlineCost, in anticipation that Caller will 310 // be removed entirely. We did not account for this above unless there 311 // is only one caller of Caller. 312 if (callerWillBeRemoved && Caller->use_begin() != Caller->use_end()) 313 TotalSecondaryCost += InlineConstants::LastCallToStaticBonus; 314 315 if (inliningPreventsSomeOuterInline && TotalSecondaryCost < IC.getCost()) { 316 DEBUG(dbgs() << " NOT Inlining: " << *CS.getInstruction() << 317 " Cost = " << IC.getCost() << 318 ", outer Cost = " << TotalSecondaryCost << '\n'); 319 return false; 320 } 321 } 322 323 DEBUG(dbgs() << " Inlining: cost=" << IC.getCost() 324 << ", thres=" << (IC.getCostDelta() + IC.getCost()) 325 << ", Call: " << *CS.getInstruction() << '\n'); 326 return true; 327} 328 329/// InlineHistoryIncludes - Return true if the specified inline history ID 330/// indicates an inline history that includes the specified function. 331static bool InlineHistoryIncludes(Function *F, int InlineHistoryID, 332 const SmallVectorImpl<std::pair<Function*, int> > &InlineHistory) { 333 while (InlineHistoryID != -1) { 334 assert(unsigned(InlineHistoryID) < InlineHistory.size() && 335 "Invalid inline history ID"); 336 if (InlineHistory[InlineHistoryID].first == F) 337 return true; 338 InlineHistoryID = InlineHistory[InlineHistoryID].second; 339 } 340 return false; 341} 342 343bool Inliner::runOnSCC(CallGraphSCC &SCC) { 344 CallGraph &CG = getAnalysis<CallGraph>(); 345 const DataLayout *TD = getAnalysisIfAvailable<DataLayout>(); 346 const TargetLibraryInfo *TLI = getAnalysisIfAvailable<TargetLibraryInfo>(); 347 348 SmallPtrSet<Function*, 8> SCCFunctions; 349 DEBUG(dbgs() << "Inliner visiting SCC:"); 350 for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) { 351 Function *F = (*I)->getFunction(); 352 if (F) SCCFunctions.insert(F); 353 DEBUG(dbgs() << " " << (F ? F->getName() : "INDIRECTNODE")); 354 } 355 356 // Scan through and identify all call sites ahead of time so that we only 357 // inline call sites in the original functions, not call sites that result 358 // from inlining other functions. 359 SmallVector<std::pair<CallSite, int>, 16> CallSites; 360 361 // When inlining a callee produces new call sites, we want to keep track of 362 // the fact that they were inlined from the callee. This allows us to avoid 363 // infinite inlining in some obscure cases. To represent this, we use an 364 // index into the InlineHistory vector. 365 SmallVector<std::pair<Function*, int>, 8> InlineHistory; 366 367 for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) { 368 Function *F = (*I)->getFunction(); 369 if (!F) continue; 370 371 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) 372 for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) { 373 CallSite CS(cast<Value>(I)); 374 // If this isn't a call, or it is a call to an intrinsic, it can 375 // never be inlined. 376 if (!CS || isa<IntrinsicInst>(I)) 377 continue; 378 379 // If this is a direct call to an external function, we can never inline 380 // it. If it is an indirect call, inlining may resolve it to be a 381 // direct call, so we keep it. 382 if (CS.getCalledFunction() && CS.getCalledFunction()->isDeclaration()) 383 continue; 384 385 CallSites.push_back(std::make_pair(CS, -1)); 386 } 387 } 388 389 DEBUG(dbgs() << ": " << CallSites.size() << " call sites.\n"); 390 391 // If there are no calls in this function, exit early. 392 if (CallSites.empty()) 393 return false; 394 395 // Now that we have all of the call sites, move the ones to functions in the 396 // current SCC to the end of the list. 397 unsigned FirstCallInSCC = CallSites.size(); 398 for (unsigned i = 0; i < FirstCallInSCC; ++i) 399 if (Function *F = CallSites[i].first.getCalledFunction()) 400 if (SCCFunctions.count(F)) 401 std::swap(CallSites[i--], CallSites[--FirstCallInSCC]); 402 403 404 InlinedArrayAllocasTy InlinedArrayAllocas; 405 InlineFunctionInfo InlineInfo(&CG, TD); 406 407 // Now that we have all of the call sites, loop over them and inline them if 408 // it looks profitable to do so. 409 bool Changed = false; 410 bool LocalChange; 411 do { 412 LocalChange = false; 413 // Iterate over the outer loop because inlining functions can cause indirect 414 // calls to become direct calls. 415 for (unsigned CSi = 0; CSi != CallSites.size(); ++CSi) { 416 CallSite CS = CallSites[CSi].first; 417 418 Function *Caller = CS.getCaller(); 419 Function *Callee = CS.getCalledFunction(); 420 421 // If this call site is dead and it is to a readonly function, we should 422 // just delete the call instead of trying to inline it, regardless of 423 // size. This happens because IPSCCP propagates the result out of the 424 // call and then we're left with the dead call. 425 if (isInstructionTriviallyDead(CS.getInstruction(), TLI)) { 426 DEBUG(dbgs() << " -> Deleting dead call: " 427 << *CS.getInstruction() << "\n"); 428 // Update the call graph by deleting the edge from Callee to Caller. 429 CG[Caller]->removeCallEdgeFor(CS); 430 CS.getInstruction()->eraseFromParent(); 431 ++NumCallsDeleted; 432 } else { 433 // We can only inline direct calls to non-declarations. 434 if (Callee == 0 || Callee->isDeclaration()) continue; 435 436 // If this call site was obtained by inlining another function, verify 437 // that the include path for the function did not include the callee 438 // itself. If so, we'd be recursively inlining the same function, 439 // which would provide the same callsites, which would cause us to 440 // infinitely inline. 441 int InlineHistoryID = CallSites[CSi].second; 442 if (InlineHistoryID != -1 && 443 InlineHistoryIncludes(Callee, InlineHistoryID, InlineHistory)) 444 continue; 445 446 447 // If the policy determines that we should inline this function, 448 // try to do so. 449 if (!shouldInline(CS)) 450 continue; 451 452 // Attempt to inline the function. 453 if (!InlineCallIfPossible(CS, InlineInfo, InlinedArrayAllocas, 454 InlineHistoryID, InsertLifetime)) 455 continue; 456 ++NumInlined; 457 458 // If inlining this function gave us any new call sites, throw them 459 // onto our worklist to process. They are useful inline candidates. 460 if (!InlineInfo.InlinedCalls.empty()) { 461 // Create a new inline history entry for this, so that we remember 462 // that these new callsites came about due to inlining Callee. 463 int NewHistoryID = InlineHistory.size(); 464 InlineHistory.push_back(std::make_pair(Callee, InlineHistoryID)); 465 466 for (unsigned i = 0, e = InlineInfo.InlinedCalls.size(); 467 i != e; ++i) { 468 Value *Ptr = InlineInfo.InlinedCalls[i]; 469 CallSites.push_back(std::make_pair(CallSite(Ptr), NewHistoryID)); 470 } 471 } 472 } 473 474 // If we inlined or deleted the last possible call site to the function, 475 // delete the function body now. 476 if (Callee && Callee->use_empty() && Callee->hasLocalLinkage() && 477 // TODO: Can remove if in SCC now. 478 !SCCFunctions.count(Callee) && 479 480 // The function may be apparently dead, but if there are indirect 481 // callgraph references to the node, we cannot delete it yet, this 482 // could invalidate the CGSCC iterator. 483 CG[Callee]->getNumReferences() == 0) { 484 DEBUG(dbgs() << " -> Deleting dead function: " 485 << Callee->getName() << "\n"); 486 CallGraphNode *CalleeNode = CG[Callee]; 487 488 // Remove any call graph edges from the callee to its callees. 489 CalleeNode->removeAllCalledFunctions(); 490 491 // Removing the node for callee from the call graph and delete it. 492 delete CG.removeFunctionFromModule(CalleeNode); 493 ++NumDeleted; 494 } 495 496 // Remove this call site from the list. If possible, use 497 // swap/pop_back for efficiency, but do not use it if doing so would 498 // move a call site to a function in this SCC before the 499 // 'FirstCallInSCC' barrier. 500 if (SCC.isSingular()) { 501 CallSites[CSi] = CallSites.back(); 502 CallSites.pop_back(); 503 } else { 504 CallSites.erase(CallSites.begin()+CSi); 505 } 506 --CSi; 507 508 Changed = true; 509 LocalChange = true; 510 } 511 } while (LocalChange); 512 513 return Changed; 514} 515 516// doFinalization - Remove now-dead linkonce functions at the end of 517// processing to avoid breaking the SCC traversal. 518bool Inliner::doFinalization(CallGraph &CG) { 519 return removeDeadFunctions(CG); 520} 521 522/// removeDeadFunctions - Remove dead functions that are not included in 523/// DNR (Do Not Remove) list. 524bool Inliner::removeDeadFunctions(CallGraph &CG, bool AlwaysInlineOnly) { 525 SmallVector<CallGraphNode*, 16> FunctionsToRemove; 526 527 // Scan for all of the functions, looking for ones that should now be removed 528 // from the program. Insert the dead ones in the FunctionsToRemove set. 529 for (CallGraph::iterator I = CG.begin(), E = CG.end(); I != E; ++I) { 530 CallGraphNode *CGN = I->second; 531 Function *F = CGN->getFunction(); 532 if (!F || F->isDeclaration()) 533 continue; 534 535 // Handle the case when this function is called and we only want to care 536 // about always-inline functions. This is a bit of a hack to share code 537 // between here and the InlineAlways pass. 538 if (AlwaysInlineOnly && 539 !F->getFnAttributes().hasAttribute(Attribute::AlwaysInline)) 540 continue; 541 542 // If the only remaining users of the function are dead constants, remove 543 // them. 544 F->removeDeadConstantUsers(); 545 546 if (!F->isDefTriviallyDead()) 547 continue; 548 549 // Remove any call graph edges from the function to its callees. 550 CGN->removeAllCalledFunctions(); 551 552 // Remove any edges from the external node to the function's call graph 553 // node. These edges might have been made irrelegant due to 554 // optimization of the program. 555 CG.getExternalCallingNode()->removeAnyCallEdgeTo(CGN); 556 557 // Removing the node for callee from the call graph and delete it. 558 FunctionsToRemove.push_back(CGN); 559 } 560 if (FunctionsToRemove.empty()) 561 return false; 562 563 // Now that we know which functions to delete, do so. We didn't want to do 564 // this inline, because that would invalidate our CallGraph::iterator 565 // objects. :( 566 // 567 // Note that it doesn't matter that we are iterating over a non-stable order 568 // here to do this, it doesn't matter which order the functions are deleted 569 // in. 570 array_pod_sort(FunctionsToRemove.begin(), FunctionsToRemove.end()); 571 FunctionsToRemove.erase(std::unique(FunctionsToRemove.begin(), 572 FunctionsToRemove.end()), 573 FunctionsToRemove.end()); 574 for (SmallVectorImpl<CallGraphNode *>::iterator I = FunctionsToRemove.begin(), 575 E = FunctionsToRemove.end(); 576 I != E; ++I) { 577 delete CG.removeFunctionFromModule(*I); 578 ++NumDeleted; 579 } 580 return true; 581} 582