Inliner.cpp revision 243830
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/Module.h" 18#include "llvm/Instructions.h" 19#include "llvm/IntrinsicInst.h" 20#include "llvm/Analysis/CallGraph.h" 21#include "llvm/Analysis/InlineCost.h" 22#include "llvm/DataLayout.h" 23#include "llvm/Target/TargetLibraryInfo.h" 24#include "llvm/Transforms/IPO/InlinerPass.h" 25#include "llvm/Transforms/Utils/Cloning.h" 26#include "llvm/Transforms/Utils/Local.h" 27#include "llvm/Support/CallSite.h" 28#include "llvm/Support/CommandLine.h" 29#include "llvm/Support/Debug.h" 30#include "llvm/Support/raw_ostream.h" 31#include "llvm/ADT/SmallPtrSet.h" 32#include "llvm/ADT/Statistic.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(Attributes::StackProtectReq)) 97 Caller->addFnAttr(Attributes::StackProtectReq); 98 else if (Callee->getFnAttributes().hasAttribute(Attributes::StackProtect) && 99 !Caller->getFnAttributes().hasAttribute(Attributes::StackProtectReq)) 100 Caller->addFnAttr(Attributes::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(Attributes::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 Function *Callee = CS.getCalledFunction(); 219 bool InlineHint = Callee && !Callee->isDeclaration() && 220 Callee->getFnAttributes().hasAttribute(Attributes::InlineHint); 221 if (InlineHint && HintThreshold > thres) 222 thres = HintThreshold; 223 224 return thres; 225} 226 227/// shouldInline - Return true if the inliner should attempt to inline 228/// at the given CallSite. 229bool Inliner::shouldInline(CallSite CS) { 230 InlineCost IC = getInlineCost(CS); 231 232 if (IC.isAlways()) { 233 DEBUG(dbgs() << " Inlining: cost=always" 234 << ", Call: " << *CS.getInstruction() << "\n"); 235 return true; 236 } 237 238 if (IC.isNever()) { 239 DEBUG(dbgs() << " NOT Inlining: cost=never" 240 << ", Call: " << *CS.getInstruction() << "\n"); 241 return false; 242 } 243 244 Function *Caller = CS.getCaller(); 245 if (!IC) { 246 DEBUG(dbgs() << " NOT Inlining: cost=" << IC.getCost() 247 << ", thres=" << (IC.getCostDelta() + IC.getCost()) 248 << ", Call: " << *CS.getInstruction() << "\n"); 249 return false; 250 } 251 252 // Try to detect the case where the current inlining candidate caller (call 253 // it B) is a static or linkonce-ODR function and is an inlining candidate 254 // elsewhere, and the current candidate callee (call it C) is large enough 255 // that inlining it into B would make B too big to inline later. In these 256 // circumstances it may be best not to inline C into B, but to inline B into 257 // its callers. 258 // 259 // This only applies to static and linkonce-ODR functions because those are 260 // expected to be available for inlining in the translation units where they 261 // are used. Thus we will always have the opportunity to make local inlining 262 // decisions. Importantly the linkonce-ODR linkage covers inline functions 263 // and templates in C++. 264 // 265 // FIXME: All of this logic should be sunk into getInlineCost. It relies on 266 // the internal implementation of the inline cost metrics rather than 267 // treating them as truly abstract units etc. 268 if (Caller->hasLocalLinkage() || 269 Caller->getLinkage() == GlobalValue::LinkOnceODRLinkage) { 270 int TotalSecondaryCost = 0; 271 // The candidate cost to be imposed upon the current function. 272 int CandidateCost = IC.getCost() - (InlineConstants::CallPenalty + 1); 273 // This bool tracks what happens if we do NOT inline C into B. 274 bool callerWillBeRemoved = Caller->hasLocalLinkage(); 275 // This bool tracks what happens if we DO inline C into B. 276 bool inliningPreventsSomeOuterInline = false; 277 for (Value::use_iterator I = Caller->use_begin(), E =Caller->use_end(); 278 I != E; ++I) { 279 CallSite CS2(*I); 280 281 // If this isn't a call to Caller (it could be some other sort 282 // of reference) skip it. Such references will prevent the caller 283 // from being removed. 284 if (!CS2 || CS2.getCalledFunction() != Caller) { 285 callerWillBeRemoved = false; 286 continue; 287 } 288 289 InlineCost IC2 = getInlineCost(CS2); 290 ++NumCallerCallersAnalyzed; 291 if (!IC2) { 292 callerWillBeRemoved = false; 293 continue; 294 } 295 if (IC2.isAlways()) 296 continue; 297 298 // See if inlining or original callsite would erase the cost delta of 299 // this callsite. We subtract off the penalty for the call instruction, 300 // which we would be deleting. 301 if (IC2.getCostDelta() <= CandidateCost) { 302 inliningPreventsSomeOuterInline = true; 303 TotalSecondaryCost += IC2.getCost(); 304 } 305 } 306 // If all outer calls to Caller would get inlined, the cost for the last 307 // one is set very low by getInlineCost, in anticipation that Caller will 308 // be removed entirely. We did not account for this above unless there 309 // is only one caller of Caller. 310 if (callerWillBeRemoved && Caller->use_begin() != Caller->use_end()) 311 TotalSecondaryCost += InlineConstants::LastCallToStaticBonus; 312 313 if (inliningPreventsSomeOuterInline && TotalSecondaryCost < IC.getCost()) { 314 DEBUG(dbgs() << " NOT Inlining: " << *CS.getInstruction() << 315 " Cost = " << IC.getCost() << 316 ", outer Cost = " << TotalSecondaryCost << '\n'); 317 return false; 318 } 319 } 320 321 DEBUG(dbgs() << " Inlining: cost=" << IC.getCost() 322 << ", thres=" << (IC.getCostDelta() + IC.getCost()) 323 << ", Call: " << *CS.getInstruction() << '\n'); 324 return true; 325} 326 327/// InlineHistoryIncludes - Return true if the specified inline history ID 328/// indicates an inline history that includes the specified function. 329static bool InlineHistoryIncludes(Function *F, int InlineHistoryID, 330 const SmallVectorImpl<std::pair<Function*, int> > &InlineHistory) { 331 while (InlineHistoryID != -1) { 332 assert(unsigned(InlineHistoryID) < InlineHistory.size() && 333 "Invalid inline history ID"); 334 if (InlineHistory[InlineHistoryID].first == F) 335 return true; 336 InlineHistoryID = InlineHistory[InlineHistoryID].second; 337 } 338 return false; 339} 340 341bool Inliner::runOnSCC(CallGraphSCC &SCC) { 342 CallGraph &CG = getAnalysis<CallGraph>(); 343 const DataLayout *TD = getAnalysisIfAvailable<DataLayout>(); 344 const TargetLibraryInfo *TLI = getAnalysisIfAvailable<TargetLibraryInfo>(); 345 346 SmallPtrSet<Function*, 8> SCCFunctions; 347 DEBUG(dbgs() << "Inliner visiting SCC:"); 348 for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) { 349 Function *F = (*I)->getFunction(); 350 if (F) SCCFunctions.insert(F); 351 DEBUG(dbgs() << " " << (F ? F->getName() : "INDIRECTNODE")); 352 } 353 354 // Scan through and identify all call sites ahead of time so that we only 355 // inline call sites in the original functions, not call sites that result 356 // from inlining other functions. 357 SmallVector<std::pair<CallSite, int>, 16> CallSites; 358 359 // When inlining a callee produces new call sites, we want to keep track of 360 // the fact that they were inlined from the callee. This allows us to avoid 361 // infinite inlining in some obscure cases. To represent this, we use an 362 // index into the InlineHistory vector. 363 SmallVector<std::pair<Function*, int>, 8> InlineHistory; 364 365 for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) { 366 Function *F = (*I)->getFunction(); 367 if (!F) continue; 368 369 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) 370 for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) { 371 CallSite CS(cast<Value>(I)); 372 // If this isn't a call, or it is a call to an intrinsic, it can 373 // never be inlined. 374 if (!CS || isa<IntrinsicInst>(I)) 375 continue; 376 377 // If this is a direct call to an external function, we can never inline 378 // it. If it is an indirect call, inlining may resolve it to be a 379 // direct call, so we keep it. 380 if (CS.getCalledFunction() && CS.getCalledFunction()->isDeclaration()) 381 continue; 382 383 CallSites.push_back(std::make_pair(CS, -1)); 384 } 385 } 386 387 DEBUG(dbgs() << ": " << CallSites.size() << " call sites.\n"); 388 389 // If there are no calls in this function, exit early. 390 if (CallSites.empty()) 391 return false; 392 393 // Now that we have all of the call sites, move the ones to functions in the 394 // current SCC to the end of the list. 395 unsigned FirstCallInSCC = CallSites.size(); 396 for (unsigned i = 0; i < FirstCallInSCC; ++i) 397 if (Function *F = CallSites[i].first.getCalledFunction()) 398 if (SCCFunctions.count(F)) 399 std::swap(CallSites[i--], CallSites[--FirstCallInSCC]); 400 401 402 InlinedArrayAllocasTy InlinedArrayAllocas; 403 InlineFunctionInfo InlineInfo(&CG, TD); 404 405 // Now that we have all of the call sites, loop over them and inline them if 406 // it looks profitable to do so. 407 bool Changed = false; 408 bool LocalChange; 409 do { 410 LocalChange = false; 411 // Iterate over the outer loop because inlining functions can cause indirect 412 // calls to become direct calls. 413 for (unsigned CSi = 0; CSi != CallSites.size(); ++CSi) { 414 CallSite CS = CallSites[CSi].first; 415 416 Function *Caller = CS.getCaller(); 417 Function *Callee = CS.getCalledFunction(); 418 419 // If this call site is dead and it is to a readonly function, we should 420 // just delete the call instead of trying to inline it, regardless of 421 // size. This happens because IPSCCP propagates the result out of the 422 // call and then we're left with the dead call. 423 if (isInstructionTriviallyDead(CS.getInstruction(), TLI)) { 424 DEBUG(dbgs() << " -> Deleting dead call: " 425 << *CS.getInstruction() << "\n"); 426 // Update the call graph by deleting the edge from Callee to Caller. 427 CG[Caller]->removeCallEdgeFor(CS); 428 CS.getInstruction()->eraseFromParent(); 429 ++NumCallsDeleted; 430 } else { 431 // We can only inline direct calls to non-declarations. 432 if (Callee == 0 || Callee->isDeclaration()) continue; 433 434 // If this call site was obtained by inlining another function, verify 435 // that the include path for the function did not include the callee 436 // itself. If so, we'd be recursively inlining the same function, 437 // which would provide the same callsites, which would cause us to 438 // infinitely inline. 439 int InlineHistoryID = CallSites[CSi].second; 440 if (InlineHistoryID != -1 && 441 InlineHistoryIncludes(Callee, InlineHistoryID, InlineHistory)) 442 continue; 443 444 445 // If the policy determines that we should inline this function, 446 // try to do so. 447 if (!shouldInline(CS)) 448 continue; 449 450 // Attempt to inline the function. 451 if (!InlineCallIfPossible(CS, InlineInfo, InlinedArrayAllocas, 452 InlineHistoryID, InsertLifetime)) 453 continue; 454 ++NumInlined; 455 456 // If inlining this function gave us any new call sites, throw them 457 // onto our worklist to process. They are useful inline candidates. 458 if (!InlineInfo.InlinedCalls.empty()) { 459 // Create a new inline history entry for this, so that we remember 460 // that these new callsites came about due to inlining Callee. 461 int NewHistoryID = InlineHistory.size(); 462 InlineHistory.push_back(std::make_pair(Callee, InlineHistoryID)); 463 464 for (unsigned i = 0, e = InlineInfo.InlinedCalls.size(); 465 i != e; ++i) { 466 Value *Ptr = InlineInfo.InlinedCalls[i]; 467 CallSites.push_back(std::make_pair(CallSite(Ptr), NewHistoryID)); 468 } 469 } 470 } 471 472 // If we inlined or deleted the last possible call site to the function, 473 // delete the function body now. 474 if (Callee && Callee->use_empty() && Callee->hasLocalLinkage() && 475 // TODO: Can remove if in SCC now. 476 !SCCFunctions.count(Callee) && 477 478 // The function may be apparently dead, but if there are indirect 479 // callgraph references to the node, we cannot delete it yet, this 480 // could invalidate the CGSCC iterator. 481 CG[Callee]->getNumReferences() == 0) { 482 DEBUG(dbgs() << " -> Deleting dead function: " 483 << Callee->getName() << "\n"); 484 CallGraphNode *CalleeNode = CG[Callee]; 485 486 // Remove any call graph edges from the callee to its callees. 487 CalleeNode->removeAllCalledFunctions(); 488 489 // Removing the node for callee from the call graph and delete it. 490 delete CG.removeFunctionFromModule(CalleeNode); 491 ++NumDeleted; 492 } 493 494 // Remove this call site from the list. If possible, use 495 // swap/pop_back for efficiency, but do not use it if doing so would 496 // move a call site to a function in this SCC before the 497 // 'FirstCallInSCC' barrier. 498 if (SCC.isSingular()) { 499 CallSites[CSi] = CallSites.back(); 500 CallSites.pop_back(); 501 } else { 502 CallSites.erase(CallSites.begin()+CSi); 503 } 504 --CSi; 505 506 Changed = true; 507 LocalChange = true; 508 } 509 } while (LocalChange); 510 511 return Changed; 512} 513 514// doFinalization - Remove now-dead linkonce functions at the end of 515// processing to avoid breaking the SCC traversal. 516bool Inliner::doFinalization(CallGraph &CG) { 517 return removeDeadFunctions(CG); 518} 519 520/// removeDeadFunctions - Remove dead functions that are not included in 521/// DNR (Do Not Remove) list. 522bool Inliner::removeDeadFunctions(CallGraph &CG, bool AlwaysInlineOnly) { 523 SmallVector<CallGraphNode*, 16> FunctionsToRemove; 524 525 // Scan for all of the functions, looking for ones that should now be removed 526 // from the program. Insert the dead ones in the FunctionsToRemove set. 527 for (CallGraph::iterator I = CG.begin(), E = CG.end(); I != E; ++I) { 528 CallGraphNode *CGN = I->second; 529 Function *F = CGN->getFunction(); 530 if (!F || F->isDeclaration()) 531 continue; 532 533 // Handle the case when this function is called and we only want to care 534 // about always-inline functions. This is a bit of a hack to share code 535 // between here and the InlineAlways pass. 536 if (AlwaysInlineOnly && 537 !F->getFnAttributes().hasAttribute(Attributes::AlwaysInline)) 538 continue; 539 540 // If the only remaining users of the function are dead constants, remove 541 // them. 542 F->removeDeadConstantUsers(); 543 544 if (!F->isDefTriviallyDead()) 545 continue; 546 547 // Remove any call graph edges from the function to its callees. 548 CGN->removeAllCalledFunctions(); 549 550 // Remove any edges from the external node to the function's call graph 551 // node. These edges might have been made irrelegant due to 552 // optimization of the program. 553 CG.getExternalCallingNode()->removeAnyCallEdgeTo(CGN); 554 555 // Removing the node for callee from the call graph and delete it. 556 FunctionsToRemove.push_back(CGN); 557 } 558 if (FunctionsToRemove.empty()) 559 return false; 560 561 // Now that we know which functions to delete, do so. We didn't want to do 562 // this inline, because that would invalidate our CallGraph::iterator 563 // objects. :( 564 // 565 // Note that it doesn't matter that we are iterating over a non-stable order 566 // here to do this, it doesn't matter which order the functions are deleted 567 // in. 568 array_pod_sort(FunctionsToRemove.begin(), FunctionsToRemove.end()); 569 FunctionsToRemove.erase(std::unique(FunctionsToRemove.begin(), 570 FunctionsToRemove.end()), 571 FunctionsToRemove.end()); 572 for (SmallVectorImpl<CallGraphNode *>::iterator I = FunctionsToRemove.begin(), 573 E = FunctionsToRemove.end(); 574 I != E; ++I) { 575 delete CG.removeFunctionFromModule(*I); 576 ++NumDeleted; 577 } 578 return true; 579} 580