1 //===- MemoryDependenceAnalysis.cpp - Mem Deps Implementation --*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements an analysis that determines, for a given memory
11 // operation, what preceding memory operations it depends on. It builds on
12 // alias analysis information, and tries to provide a lazy, caching interface to
13 // a common kind of alias information query.
15 //===----------------------------------------------------------------------===//
17 #define DEBUG_TYPE "memdep"
18 #include "llvm/Analysis/MemoryDependenceAnalysis.h"
19 #include "llvm/Instructions.h"
20 #include "llvm/IntrinsicInst.h"
21 #include "llvm/Function.h"
22 #include "llvm/Analysis/AliasAnalysis.h"
23 #include "llvm/Analysis/Dominators.h"
24 #include "llvm/Analysis/InstructionSimplify.h"
25 #include "llvm/Analysis/MemoryBuiltins.h"
26 #include "llvm/Analysis/PHITransAddr.h"
27 #include "llvm/ADT/Statistic.h"
28 #include "llvm/ADT/STLExtras.h"
29 #include "llvm/Support/PredIteratorCache.h"
30 #include "llvm/Support/Debug.h"
33 STATISTIC(NumCacheNonLocal, "Number of fully cached non-local responses");
34 STATISTIC(NumCacheDirtyNonLocal, "Number of dirty cached non-local responses");
35 STATISTIC(NumUncacheNonLocal, "Number of uncached non-local responses");
37 STATISTIC(NumCacheNonLocalPtr,
38 "Number of fully cached non-local ptr responses");
39 STATISTIC(NumCacheDirtyNonLocalPtr,
40 "Number of cached, but dirty, non-local ptr responses");
41 STATISTIC(NumUncacheNonLocalPtr,
42 "Number of uncached non-local ptr responses");
43 STATISTIC(NumCacheCompleteNonLocalPtr,
44 "Number of block queries that were completely cached");
46 char MemoryDependenceAnalysis::ID = 0;
48 // Register this pass...
49 static RegisterPass<MemoryDependenceAnalysis> X("memdep",
50 "Memory Dependence Analysis", false, true);
52 MemoryDependenceAnalysis::MemoryDependenceAnalysis()
53 : FunctionPass(&ID), PredCache(0) {
55 MemoryDependenceAnalysis::~MemoryDependenceAnalysis() {
58 /// Clean up memory in between runs
59 void MemoryDependenceAnalysis::releaseMemory() {
62 NonLocalPointerDeps.clear();
63 ReverseLocalDeps.clear();
64 ReverseNonLocalDeps.clear();
65 ReverseNonLocalPtrDeps.clear();
71 /// getAnalysisUsage - Does not modify anything. It uses Alias Analysis.
73 void MemoryDependenceAnalysis::getAnalysisUsage(AnalysisUsage &AU) const {
75 AU.addRequiredTransitive<AliasAnalysis>();
78 bool MemoryDependenceAnalysis::runOnFunction(Function &) {
79 AA = &getAnalysis<AliasAnalysis>();
81 PredCache.reset(new PredIteratorCache());
85 /// RemoveFromReverseMap - This is a helper function that removes Val from
86 /// 'Inst's set in ReverseMap. If the set becomes empty, remove Inst's entry.
87 template <typename KeyTy>
88 static void RemoveFromReverseMap(DenseMap<Instruction*,
89 SmallPtrSet<KeyTy, 4> > &ReverseMap,
90 Instruction *Inst, KeyTy Val) {
91 typename DenseMap<Instruction*, SmallPtrSet<KeyTy, 4> >::iterator
92 InstIt = ReverseMap.find(Inst);
93 assert(InstIt != ReverseMap.end() && "Reverse map out of sync?");
94 bool Found = InstIt->second.erase(Val);
95 assert(Found && "Invalid reverse map!"); Found=Found;
96 if (InstIt->second.empty())
97 ReverseMap.erase(InstIt);
101 /// getCallSiteDependencyFrom - Private helper for finding the local
102 /// dependencies of a call site.
103 MemDepResult MemoryDependenceAnalysis::
104 getCallSiteDependencyFrom(CallSite CS, bool isReadOnlyCall,
105 BasicBlock::iterator ScanIt, BasicBlock *BB) {
106 // Walk backwards through the block, looking for dependencies
107 while (ScanIt != BB->begin()) {
108 Instruction *Inst = --ScanIt;
110 // If this inst is a memory op, get the pointer it accessed
112 uint64_t PointerSize = 0;
113 if (StoreInst *S = dyn_cast<StoreInst>(Inst)) {
114 Pointer = S->getPointerOperand();
115 PointerSize = AA->getTypeStoreSize(S->getOperand(0)->getType());
116 } else if (VAArgInst *V = dyn_cast<VAArgInst>(Inst)) {
117 Pointer = V->getOperand(0);
118 PointerSize = AA->getTypeStoreSize(V->getType());
119 } else if (isFreeCall(Inst)) {
120 Pointer = Inst->getOperand(1);
121 // calls to free() erase the entire structure
123 } else if (isa<CallInst>(Inst) || isa<InvokeInst>(Inst)) {
124 // Debug intrinsics don't cause dependences.
125 if (isa<DbgInfoIntrinsic>(Inst)) continue;
126 CallSite InstCS = CallSite::get(Inst);
127 // If these two calls do not interfere, look past it.
128 switch (AA->getModRefInfo(CS, InstCS)) {
129 case AliasAnalysis::NoModRef:
130 // If the two calls don't interact (e.g. InstCS is readnone) keep
133 case AliasAnalysis::Ref:
134 // If the two calls read the same memory locations and CS is a readonly
135 // function, then we have two cases: 1) the calls may not interfere with
136 // each other at all. 2) the calls may produce the same value. In case
137 // #1 we want to ignore the values, in case #2, we want to return Inst
138 // as a Def dependence. This allows us to CSE in cases like:
141 // Y = strlen(P); // Y = X
142 if (isReadOnlyCall) {
143 if (CS.getCalledFunction() != 0 &&
144 CS.getCalledFunction() == InstCS.getCalledFunction())
145 return MemDepResult::getDef(Inst);
146 // Ignore unrelated read/read call dependences.
151 return MemDepResult::getClobber(Inst);
154 // Non-memory instruction.
158 if (AA->getModRefInfo(CS, Pointer, PointerSize) != AliasAnalysis::NoModRef)
159 return MemDepResult::getClobber(Inst);
162 // No dependence found. If this is the entry block of the function, it is a
163 // clobber, otherwise it is non-local.
164 if (BB != &BB->getParent()->getEntryBlock())
165 return MemDepResult::getNonLocal();
166 return MemDepResult::getClobber(ScanIt);
169 /// getPointerDependencyFrom - Return the instruction on which a memory
170 /// location depends. If isLoad is true, this routine ignore may-aliases with
171 /// read-only operations.
172 MemDepResult MemoryDependenceAnalysis::
173 getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad,
174 BasicBlock::iterator ScanIt, BasicBlock *BB) {
176 Value *InvariantTag = 0;
178 // Walk backwards through the basic block, looking for dependencies.
179 while (ScanIt != BB->begin()) {
180 Instruction *Inst = --ScanIt;
182 // If we're in an invariant region, no dependencies can be found before
183 // we pass an invariant-begin marker.
184 if (InvariantTag == Inst) {
189 if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(Inst)) {
190 // Debug intrinsics don't cause dependences.
191 if (isa<DbgInfoIntrinsic>(Inst)) continue;
193 // If we pass an invariant-end marker, then we've just entered an
194 // invariant region and can start ignoring dependencies.
195 if (II->getIntrinsicID() == Intrinsic::invariant_end) {
196 // FIXME: This only considers queries directly on the invariant-tagged
197 // pointer, not on query pointers that are indexed off of them. It'd
198 // be nice to handle that at some point.
199 AliasAnalysis::AliasResult R =
200 AA->alias(II->getOperand(3), ~0U, MemPtr, ~0U);
201 if (R == AliasAnalysis::MustAlias) {
202 InvariantTag = II->getOperand(1);
206 // If we reach a lifetime begin or end marker, then the query ends here
207 // because the value is undefined.
208 } else if (II->getIntrinsicID() == Intrinsic::lifetime_start) {
209 // FIXME: This only considers queries directly on the invariant-tagged
210 // pointer, not on query pointers that are indexed off of them. It'd
211 // be nice to handle that at some point.
212 AliasAnalysis::AliasResult R =
213 AA->alias(II->getOperand(2), ~0U, MemPtr, ~0U);
214 if (R == AliasAnalysis::MustAlias)
215 return MemDepResult::getDef(II);
219 // If we're querying on a load and we're in an invariant region, we're done
220 // at this point. Nothing a load depends on can live in an invariant region.
221 if (isLoad && InvariantTag) continue;
223 // Values depend on loads if the pointers are must aliased. This means that
224 // a load depends on another must aliased load from the same value.
225 if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) {
226 Value *Pointer = LI->getPointerOperand();
227 uint64_t PointerSize = AA->getTypeStoreSize(LI->getType());
229 // If we found a pointer, check if it could be the same as our pointer.
230 AliasAnalysis::AliasResult R =
231 AA->alias(Pointer, PointerSize, MemPtr, MemSize);
232 if (R == AliasAnalysis::NoAlias)
235 // May-alias loads don't depend on each other without a dependence.
236 if (isLoad && R == AliasAnalysis::MayAlias)
238 // Stores depend on may and must aliased loads, loads depend on must-alias
240 return MemDepResult::getDef(Inst);
243 if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
244 // There can't be stores to the value we care about inside an
246 if (InvariantTag) continue;
248 // If alias analysis can tell that this store is guaranteed to not modify
249 // the query pointer, ignore it. Use getModRefInfo to handle cases where
250 // the query pointer points to constant memory etc.
251 if (AA->getModRefInfo(SI, MemPtr, MemSize) == AliasAnalysis::NoModRef)
254 // Ok, this store might clobber the query pointer. Check to see if it is
255 // a must alias: in this case, we want to return this as a def.
256 Value *Pointer = SI->getPointerOperand();
257 uint64_t PointerSize = AA->getTypeStoreSize(SI->getOperand(0)->getType());
259 // If we found a pointer, check if it could be the same as our pointer.
260 AliasAnalysis::AliasResult R =
261 AA->alias(Pointer, PointerSize, MemPtr, MemSize);
263 if (R == AliasAnalysis::NoAlias)
265 if (R == AliasAnalysis::MayAlias)
266 return MemDepResult::getClobber(Inst);
267 return MemDepResult::getDef(Inst);
270 // If this is an allocation, and if we know that the accessed pointer is to
271 // the allocation, return Def. This means that there is no dependence and
272 // the access can be optimized based on that. For example, a load could
274 // Note: Only determine this to be a malloc if Inst is the malloc call, not
275 // a subsequent bitcast of the malloc call result. There can be stores to
276 // the malloced memory between the malloc call and its bitcast uses, and we
277 // need to continue scanning until the malloc call.
278 if (isa<AllocaInst>(Inst) || extractMallocCall(Inst)) {
279 Value *AccessPtr = MemPtr->getUnderlyingObject();
281 if (AccessPtr == Inst ||
282 AA->alias(Inst, 1, AccessPtr, 1) == AliasAnalysis::MustAlias)
283 return MemDepResult::getDef(Inst);
287 // See if this instruction (e.g. a call or vaarg) mod/ref's the pointer.
288 switch (AA->getModRefInfo(Inst, MemPtr, MemSize)) {
289 case AliasAnalysis::NoModRef:
290 // If the call has no effect on the queried pointer, just ignore it.
292 case AliasAnalysis::Mod:
293 // If we're in an invariant region, we can ignore calls that ONLY
294 // modify the pointer.
295 if (InvariantTag) continue;
296 return MemDepResult::getClobber(Inst);
297 case AliasAnalysis::Ref:
298 // If the call is known to never store to the pointer, and if this is a
299 // load query, we can safely ignore it (scan past it).
303 // Otherwise, there is a potential dependence. Return a clobber.
304 return MemDepResult::getClobber(Inst);
308 // No dependence found. If this is the entry block of the function, it is a
309 // clobber, otherwise it is non-local.
310 if (BB != &BB->getParent()->getEntryBlock())
311 return MemDepResult::getNonLocal();
312 return MemDepResult::getClobber(ScanIt);
315 /// getDependency - Return the instruction on which a memory operation
317 MemDepResult MemoryDependenceAnalysis::getDependency(Instruction *QueryInst) {
318 Instruction *ScanPos = QueryInst;
320 // Check for a cached result
321 MemDepResult &LocalCache = LocalDeps[QueryInst];
323 // If the cached entry is non-dirty, just return it. Note that this depends
324 // on MemDepResult's default constructing to 'dirty'.
325 if (!LocalCache.isDirty())
328 // Otherwise, if we have a dirty entry, we know we can start the scan at that
329 // instruction, which may save us some work.
330 if (Instruction *Inst = LocalCache.getInst()) {
333 RemoveFromReverseMap(ReverseLocalDeps, Inst, QueryInst);
336 BasicBlock *QueryParent = QueryInst->getParent();
339 uint64_t MemSize = 0;
342 if (BasicBlock::iterator(QueryInst) == QueryParent->begin()) {
343 // No dependence found. If this is the entry block of the function, it is a
344 // clobber, otherwise it is non-local.
345 if (QueryParent != &QueryParent->getParent()->getEntryBlock())
346 LocalCache = MemDepResult::getNonLocal();
348 LocalCache = MemDepResult::getClobber(QueryInst);
349 } else if (StoreInst *SI = dyn_cast<StoreInst>(QueryInst)) {
350 // If this is a volatile store, don't mess around with it. Just return the
351 // previous instruction as a clobber.
352 if (SI->isVolatile())
353 LocalCache = MemDepResult::getClobber(--BasicBlock::iterator(ScanPos));
355 MemPtr = SI->getPointerOperand();
356 MemSize = AA->getTypeStoreSize(SI->getOperand(0)->getType());
358 } else if (LoadInst *LI = dyn_cast<LoadInst>(QueryInst)) {
359 // If this is a volatile load, don't mess around with it. Just return the
360 // previous instruction as a clobber.
361 if (LI->isVolatile())
362 LocalCache = MemDepResult::getClobber(--BasicBlock::iterator(ScanPos));
364 MemPtr = LI->getPointerOperand();
365 MemSize = AA->getTypeStoreSize(LI->getType());
367 } else if (isFreeCall(QueryInst)) {
368 MemPtr = QueryInst->getOperand(1);
369 // calls to free() erase the entire structure, not just a field.
371 } else if (isa<CallInst>(QueryInst) || isa<InvokeInst>(QueryInst)) {
372 int IntrinsicID = 0; // Intrinsic IDs start at 1.
373 if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(QueryInst))
374 IntrinsicID = II->getIntrinsicID();
376 switch (IntrinsicID) {
377 case Intrinsic::lifetime_start:
378 case Intrinsic::lifetime_end:
379 case Intrinsic::invariant_start:
380 MemPtr = QueryInst->getOperand(2);
381 MemSize = cast<ConstantInt>(QueryInst->getOperand(1))->getZExtValue();
383 case Intrinsic::invariant_end:
384 MemPtr = QueryInst->getOperand(3);
385 MemSize = cast<ConstantInt>(QueryInst->getOperand(2))->getZExtValue();
388 CallSite QueryCS = CallSite::get(QueryInst);
389 bool isReadOnly = AA->onlyReadsMemory(QueryCS);
390 LocalCache = getCallSiteDependencyFrom(QueryCS, isReadOnly, ScanPos,
395 // Non-memory instruction.
396 LocalCache = MemDepResult::getClobber(--BasicBlock::iterator(ScanPos));
399 // If we need to do a pointer scan, make it happen.
401 bool isLoad = !QueryInst->mayWriteToMemory();
402 if (IntrinsicInst *II = dyn_cast<MemoryUseIntrinsic>(QueryInst)) {
403 isLoad |= II->getIntrinsicID() == Intrinsic::lifetime_end;
405 LocalCache = getPointerDependencyFrom(MemPtr, MemSize, isLoad, ScanPos,
409 // Remember the result!
410 if (Instruction *I = LocalCache.getInst())
411 ReverseLocalDeps[I].insert(QueryInst);
417 /// AssertSorted - This method is used when -debug is specified to verify that
418 /// cache arrays are properly kept sorted.
419 static void AssertSorted(MemoryDependenceAnalysis::NonLocalDepInfo &Cache,
421 if (Count == -1) Count = Cache.size();
422 if (Count == 0) return;
424 for (unsigned i = 1; i != unsigned(Count); ++i)
425 assert(!(Cache[i] < Cache[i-1]) && "Cache isn't sorted!");
429 /// getNonLocalCallDependency - Perform a full dependency query for the
430 /// specified call, returning the set of blocks that the value is
431 /// potentially live across. The returned set of results will include a
432 /// "NonLocal" result for all blocks where the value is live across.
434 /// This method assumes the instruction returns a "NonLocal" dependency
435 /// within its own block.
437 /// This returns a reference to an internal data structure that may be
438 /// invalidated on the next non-local query or when an instruction is
439 /// removed. Clients must copy this data if they want it around longer than
441 const MemoryDependenceAnalysis::NonLocalDepInfo &
442 MemoryDependenceAnalysis::getNonLocalCallDependency(CallSite QueryCS) {
443 assert(getDependency(QueryCS.getInstruction()).isNonLocal() &&
444 "getNonLocalCallDependency should only be used on calls with non-local deps!");
445 PerInstNLInfo &CacheP = NonLocalDeps[QueryCS.getInstruction()];
446 NonLocalDepInfo &Cache = CacheP.first;
448 /// DirtyBlocks - This is the set of blocks that need to be recomputed. In
449 /// the cached case, this can happen due to instructions being deleted etc. In
450 /// the uncached case, this starts out as the set of predecessors we care
452 SmallVector<BasicBlock*, 32> DirtyBlocks;
454 if (!Cache.empty()) {
455 // Okay, we have a cache entry. If we know it is not dirty, just return it
456 // with no computation.
457 if (!CacheP.second) {
462 // If we already have a partially computed set of results, scan them to
463 // determine what is dirty, seeding our initial DirtyBlocks worklist.
464 for (NonLocalDepInfo::iterator I = Cache.begin(), E = Cache.end();
466 if (I->getResult().isDirty())
467 DirtyBlocks.push_back(I->getBB());
469 // Sort the cache so that we can do fast binary search lookups below.
470 std::sort(Cache.begin(), Cache.end());
472 ++NumCacheDirtyNonLocal;
473 //cerr << "CACHED CASE: " << DirtyBlocks.size() << " dirty: "
474 // << Cache.size() << " cached: " << *QueryInst;
476 // Seed DirtyBlocks with each of the preds of QueryInst's block.
477 BasicBlock *QueryBB = QueryCS.getInstruction()->getParent();
478 for (BasicBlock **PI = PredCache->GetPreds(QueryBB); *PI; ++PI)
479 DirtyBlocks.push_back(*PI);
480 NumUncacheNonLocal++;
483 // isReadonlyCall - If this is a read-only call, we can be more aggressive.
484 bool isReadonlyCall = AA->onlyReadsMemory(QueryCS);
486 SmallPtrSet<BasicBlock*, 64> Visited;
488 unsigned NumSortedEntries = Cache.size();
489 DEBUG(AssertSorted(Cache));
491 // Iterate while we still have blocks to update.
492 while (!DirtyBlocks.empty()) {
493 BasicBlock *DirtyBB = DirtyBlocks.back();
494 DirtyBlocks.pop_back();
496 // Already processed this block?
497 if (!Visited.insert(DirtyBB))
500 // Do a binary search to see if we already have an entry for this block in
501 // the cache set. If so, find it.
502 DEBUG(AssertSorted(Cache, NumSortedEntries));
503 NonLocalDepInfo::iterator Entry =
504 std::upper_bound(Cache.begin(), Cache.begin()+NumSortedEntries,
505 NonLocalDepEntry(DirtyBB));
506 if (Entry != Cache.begin() && prior(Entry)->getBB() == DirtyBB)
509 NonLocalDepEntry *ExistingResult = 0;
510 if (Entry != Cache.begin()+NumSortedEntries &&
511 Entry->getBB() == DirtyBB) {
512 // If we already have an entry, and if it isn't already dirty, the block
514 if (!Entry->getResult().isDirty())
517 // Otherwise, remember this slot so we can update the value.
518 ExistingResult = &*Entry;
521 // If the dirty entry has a pointer, start scanning from it so we don't have
522 // to rescan the entire block.
523 BasicBlock::iterator ScanPos = DirtyBB->end();
524 if (ExistingResult) {
525 if (Instruction *Inst = ExistingResult->getResult().getInst()) {
527 // We're removing QueryInst's use of Inst.
528 RemoveFromReverseMap(ReverseNonLocalDeps, Inst,
529 QueryCS.getInstruction());
533 // Find out if this block has a local dependency for QueryInst.
536 if (ScanPos != DirtyBB->begin()) {
537 Dep = getCallSiteDependencyFrom(QueryCS, isReadonlyCall,ScanPos, DirtyBB);
538 } else if (DirtyBB != &DirtyBB->getParent()->getEntryBlock()) {
539 // No dependence found. If this is the entry block of the function, it is
540 // a clobber, otherwise it is non-local.
541 Dep = MemDepResult::getNonLocal();
543 Dep = MemDepResult::getClobber(ScanPos);
546 // If we had a dirty entry for the block, update it. Otherwise, just add
549 ExistingResult->setResult(Dep, 0);
551 Cache.push_back(NonLocalDepEntry(DirtyBB, Dep, 0));
553 // If the block has a dependency (i.e. it isn't completely transparent to
554 // the value), remember the association!
555 if (!Dep.isNonLocal()) {
556 // Keep the ReverseNonLocalDeps map up to date so we can efficiently
557 // update this when we remove instructions.
558 if (Instruction *Inst = Dep.getInst())
559 ReverseNonLocalDeps[Inst].insert(QueryCS.getInstruction());
562 // If the block *is* completely transparent to the load, we need to check
563 // the predecessors of this block. Add them to our worklist.
564 for (BasicBlock **PI = PredCache->GetPreds(DirtyBB); *PI; ++PI)
565 DirtyBlocks.push_back(*PI);
572 /// getNonLocalPointerDependency - Perform a full dependency query for an
573 /// access to the specified (non-volatile) memory location, returning the
574 /// set of instructions that either define or clobber the value.
576 /// This method assumes the pointer has a "NonLocal" dependency within its
579 void MemoryDependenceAnalysis::
580 getNonLocalPointerDependency(Value *Pointer, bool isLoad, BasicBlock *FromBB,
581 SmallVectorImpl<NonLocalDepEntry> &Result) {
582 assert(isa<PointerType>(Pointer->getType()) &&
583 "Can't get pointer deps of a non-pointer!");
586 // We know that the pointer value is live into FromBB find the def/clobbers
587 // from presecessors.
588 const Type *EltTy = cast<PointerType>(Pointer->getType())->getElementType();
589 uint64_t PointeeSize = AA->getTypeStoreSize(EltTy);
591 PHITransAddr Address(Pointer, TD);
593 // This is the set of blocks we've inspected, and the pointer we consider in
594 // each block. Because of critical edges, we currently bail out if querying
595 // a block with multiple different pointers. This can happen during PHI
597 DenseMap<BasicBlock*, Value*> Visited;
598 if (!getNonLocalPointerDepFromBB(Address, PointeeSize, isLoad, FromBB,
599 Result, Visited, true))
602 Result.push_back(NonLocalDepEntry(FromBB,
603 MemDepResult::getClobber(FromBB->begin()),
607 /// GetNonLocalInfoForBlock - Compute the memdep value for BB with
608 /// Pointer/PointeeSize using either cached information in Cache or by doing a
609 /// lookup (which may use dirty cache info if available). If we do a lookup,
610 /// add the result to the cache.
611 MemDepResult MemoryDependenceAnalysis::
612 GetNonLocalInfoForBlock(Value *Pointer, uint64_t PointeeSize,
613 bool isLoad, BasicBlock *BB,
614 NonLocalDepInfo *Cache, unsigned NumSortedEntries) {
616 // Do a binary search to see if we already have an entry for this block in
617 // the cache set. If so, find it.
618 NonLocalDepInfo::iterator Entry =
619 std::upper_bound(Cache->begin(), Cache->begin()+NumSortedEntries,
620 NonLocalDepEntry(BB));
621 if (Entry != Cache->begin() && (Entry-1)->getBB() == BB)
624 NonLocalDepEntry *ExistingResult = 0;
625 if (Entry != Cache->begin()+NumSortedEntries && Entry->getBB() == BB)
626 ExistingResult = &*Entry;
628 // If we have a cached entry, and it is non-dirty, use it as the value for
630 if (ExistingResult && !ExistingResult->getResult().isDirty()) {
631 ++NumCacheNonLocalPtr;
632 return ExistingResult->getResult();
635 // Otherwise, we have to scan for the value. If we have a dirty cache
636 // entry, start scanning from its position, otherwise we scan from the end
638 BasicBlock::iterator ScanPos = BB->end();
639 if (ExistingResult && ExistingResult->getResult().getInst()) {
640 assert(ExistingResult->getResult().getInst()->getParent() == BB &&
641 "Instruction invalidated?");
642 ++NumCacheDirtyNonLocalPtr;
643 ScanPos = ExistingResult->getResult().getInst();
645 // Eliminating the dirty entry from 'Cache', so update the reverse info.
646 ValueIsLoadPair CacheKey(Pointer, isLoad);
647 RemoveFromReverseMap(ReverseNonLocalPtrDeps, ScanPos, CacheKey);
649 ++NumUncacheNonLocalPtr;
652 // Scan the block for the dependency.
653 MemDepResult Dep = getPointerDependencyFrom(Pointer, PointeeSize, isLoad,
656 // If we had a dirty entry for the block, update it. Otherwise, just add
659 ExistingResult->setResult(Dep, Pointer);
661 Cache->push_back(NonLocalDepEntry(BB, Dep, Pointer));
663 // If the block has a dependency (i.e. it isn't completely transparent to
664 // the value), remember the reverse association because we just added it
666 if (Dep.isNonLocal())
669 // Keep the ReverseNonLocalPtrDeps map up to date so we can efficiently
670 // update MemDep when we remove instructions.
671 Instruction *Inst = Dep.getInst();
672 assert(Inst && "Didn't depend on anything?");
673 ValueIsLoadPair CacheKey(Pointer, isLoad);
674 ReverseNonLocalPtrDeps[Inst].insert(CacheKey);
678 /// SortNonLocalDepInfoCache - Sort the a NonLocalDepInfo cache, given a certain
679 /// number of elements in the array that are already properly ordered. This is
680 /// optimized for the case when only a few entries are added.
682 SortNonLocalDepInfoCache(MemoryDependenceAnalysis::NonLocalDepInfo &Cache,
683 unsigned NumSortedEntries) {
684 switch (Cache.size() - NumSortedEntries) {
686 // done, no new entries.
689 // Two new entries, insert the last one into place.
690 NonLocalDepEntry Val = Cache.back();
692 MemoryDependenceAnalysis::NonLocalDepInfo::iterator Entry =
693 std::upper_bound(Cache.begin(), Cache.end()-1, Val);
694 Cache.insert(Entry, Val);
698 // One new entry, Just insert the new value at the appropriate position.
699 if (Cache.size() != 1) {
700 NonLocalDepEntry Val = Cache.back();
702 MemoryDependenceAnalysis::NonLocalDepInfo::iterator Entry =
703 std::upper_bound(Cache.begin(), Cache.end(), Val);
704 Cache.insert(Entry, Val);
708 // Added many values, do a full scale sort.
709 std::sort(Cache.begin(), Cache.end());
714 /// getNonLocalPointerDepFromBB - Perform a dependency query based on
715 /// pointer/pointeesize starting at the end of StartBB. Add any clobber/def
716 /// results to the results vector and keep track of which blocks are visited in
719 /// This has special behavior for the first block queries (when SkipFirstBlock
720 /// is true). In this special case, it ignores the contents of the specified
721 /// block and starts returning dependence info for its predecessors.
723 /// This function returns false on success, or true to indicate that it could
724 /// not compute dependence information for some reason. This should be treated
725 /// as a clobber dependence on the first instruction in the predecessor block.
726 bool MemoryDependenceAnalysis::
727 getNonLocalPointerDepFromBB(const PHITransAddr &Pointer, uint64_t PointeeSize,
728 bool isLoad, BasicBlock *StartBB,
729 SmallVectorImpl<NonLocalDepEntry> &Result,
730 DenseMap<BasicBlock*, Value*> &Visited,
731 bool SkipFirstBlock) {
733 // Look up the cached info for Pointer.
734 ValueIsLoadPair CacheKey(Pointer.getAddr(), isLoad);
736 std::pair<BBSkipFirstBlockPair, NonLocalDepInfo> *CacheInfo =
737 &NonLocalPointerDeps[CacheKey];
738 NonLocalDepInfo *Cache = &CacheInfo->second;
740 // If we have valid cached information for exactly the block we are
741 // investigating, just return it with no recomputation.
742 if (CacheInfo->first == BBSkipFirstBlockPair(StartBB, SkipFirstBlock)) {
743 // We have a fully cached result for this query then we can just return the
744 // cached results and populate the visited set. However, we have to verify
745 // that we don't already have conflicting results for these blocks. Check
746 // to ensure that if a block in the results set is in the visited set that
747 // it was for the same pointer query.
748 if (!Visited.empty()) {
749 for (NonLocalDepInfo::iterator I = Cache->begin(), E = Cache->end();
751 DenseMap<BasicBlock*, Value*>::iterator VI = Visited.find(I->getBB());
752 if (VI == Visited.end() || VI->second == Pointer.getAddr())
755 // We have a pointer mismatch in a block. Just return clobber, saying
756 // that something was clobbered in this result. We could also do a
757 // non-fully cached query, but there is little point in doing this.
762 for (NonLocalDepInfo::iterator I = Cache->begin(), E = Cache->end();
764 Visited.insert(std::make_pair(I->getBB(), Pointer.getAddr()));
765 if (!I->getResult().isNonLocal())
766 Result.push_back(*I);
768 ++NumCacheCompleteNonLocalPtr;
772 // Otherwise, either this is a new block, a block with an invalid cache
773 // pointer or one that we're about to invalidate by putting more info into it
774 // than its valid cache info. If empty, the result will be valid cache info,
775 // otherwise it isn't.
777 CacheInfo->first = BBSkipFirstBlockPair(StartBB, SkipFirstBlock);
779 CacheInfo->first = BBSkipFirstBlockPair();
781 SmallVector<BasicBlock*, 32> Worklist;
782 Worklist.push_back(StartBB);
784 // Keep track of the entries that we know are sorted. Previously cached
785 // entries will all be sorted. The entries we add we only sort on demand (we
786 // don't insert every element into its sorted position). We know that we
787 // won't get any reuse from currently inserted values, because we don't
788 // revisit blocks after we insert info for them.
789 unsigned NumSortedEntries = Cache->size();
790 DEBUG(AssertSorted(*Cache));
792 while (!Worklist.empty()) {
793 BasicBlock *BB = Worklist.pop_back_val();
795 // Skip the first block if we have it.
796 if (!SkipFirstBlock) {
797 // Analyze the dependency of *Pointer in FromBB. See if we already have
799 assert(Visited.count(BB) && "Should check 'visited' before adding to WL");
801 // Get the dependency info for Pointer in BB. If we have cached
802 // information, we will use it, otherwise we compute it.
803 DEBUG(AssertSorted(*Cache, NumSortedEntries));
804 MemDepResult Dep = GetNonLocalInfoForBlock(Pointer.getAddr(), PointeeSize,
808 // If we got a Def or Clobber, add this to the list of results.
809 if (!Dep.isNonLocal()) {
810 Result.push_back(NonLocalDepEntry(BB, Dep, Pointer.getAddr()));
815 // If 'Pointer' is an instruction defined in this block, then we need to do
816 // phi translation to change it into a value live in the predecessor block.
817 // If not, we just add the predecessors to the worklist and scan them with
819 if (!Pointer.NeedsPHITranslationFromBlock(BB)) {
820 SkipFirstBlock = false;
821 for (BasicBlock **PI = PredCache->GetPreds(BB); *PI; ++PI) {
822 // Verify that we haven't looked at this block yet.
823 std::pair<DenseMap<BasicBlock*,Value*>::iterator, bool>
824 InsertRes = Visited.insert(std::make_pair(*PI, Pointer.getAddr()));
825 if (InsertRes.second) {
826 // First time we've looked at *PI.
827 Worklist.push_back(*PI);
831 // If we have seen this block before, but it was with a different
832 // pointer then we have a phi translation failure and we have to treat
833 // this as a clobber.
834 if (InsertRes.first->second != Pointer.getAddr())
835 goto PredTranslationFailure;
840 // We do need to do phi translation, if we know ahead of time we can't phi
841 // translate this value, don't even try.
842 if (!Pointer.IsPotentiallyPHITranslatable())
843 goto PredTranslationFailure;
845 // We may have added values to the cache list before this PHI translation.
846 // If so, we haven't done anything to ensure that the cache remains sorted.
847 // Sort it now (if needed) so that recursive invocations of
848 // getNonLocalPointerDepFromBB and other routines that could reuse the cache
849 // value will only see properly sorted cache arrays.
850 if (Cache && NumSortedEntries != Cache->size()) {
851 SortNonLocalDepInfoCache(*Cache, NumSortedEntries);
852 NumSortedEntries = Cache->size();
856 for (BasicBlock **PI = PredCache->GetPreds(BB); *PI; ++PI) {
857 BasicBlock *Pred = *PI;
859 // Get the PHI translated pointer in this predecessor. This can fail if
860 // not translatable, in which case the getAddr() returns null.
861 PHITransAddr PredPointer(Pointer);
862 PredPointer.PHITranslateValue(BB, Pred);
864 Value *PredPtrVal = PredPointer.getAddr();
866 // Check to see if we have already visited this pred block with another
867 // pointer. If so, we can't do this lookup. This failure can occur
868 // with PHI translation when a critical edge exists and the PHI node in
869 // the successor translates to a pointer value different than the
870 // pointer the block was first analyzed with.
871 std::pair<DenseMap<BasicBlock*,Value*>::iterator, bool>
872 InsertRes = Visited.insert(std::make_pair(Pred, PredPtrVal));
874 if (!InsertRes.second) {
875 // If the predecessor was visited with PredPtr, then we already did
876 // the analysis and can ignore it.
877 if (InsertRes.first->second == PredPtrVal)
880 // Otherwise, the block was previously analyzed with a different
881 // pointer. We can't represent the result of this case, so we just
882 // treat this as a phi translation failure.
883 goto PredTranslationFailure;
886 // If PHI translation was unable to find an available pointer in this
887 // predecessor, then we have to assume that the pointer is clobbered in
888 // that predecessor. We can still do PRE of the load, which would insert
889 // a computation of the pointer in this predecessor.
890 if (PredPtrVal == 0) {
891 // Add the entry to the Result list.
892 NonLocalDepEntry Entry(Pred,
893 MemDepResult::getClobber(Pred->getTerminator()),
895 Result.push_back(Entry);
897 // Add it to the cache for this CacheKey so that subsequent queries get
899 Cache = &NonLocalPointerDeps[CacheKey].second;
900 MemoryDependenceAnalysis::NonLocalDepInfo::iterator It =
901 std::upper_bound(Cache->begin(), Cache->end(), Entry);
903 if (It != Cache->begin() && (It-1)->getBB() == Pred)
906 if (It == Cache->end() || It->getBB() != Pred) {
907 Cache->insert(It, Entry);
908 // Add it to the reverse map.
909 ReverseNonLocalPtrDeps[Pred->getTerminator()].insert(CacheKey);
910 } else if (!It->getResult().isDirty()) {
912 } else if (It->getResult().getInst() == Pred->getTerminator()) {
913 // Same instruction, clear the dirty marker.
914 It->setResult(Entry.getResult(), PredPtrVal);
915 } else if (It->getResult().getInst() == 0) {
916 // Dirty, with no instruction, just add this.
917 It->setResult(Entry.getResult(), PredPtrVal);
918 ReverseNonLocalPtrDeps[Pred->getTerminator()].insert(CacheKey);
920 // Otherwise, dirty with a different instruction.
921 RemoveFromReverseMap(ReverseNonLocalPtrDeps,
922 It->getResult().getInst(), CacheKey);
923 It->setResult(Entry.getResult(),PredPtrVal);
924 ReverseNonLocalPtrDeps[Pred->getTerminator()].insert(CacheKey);
930 // FIXME: it is entirely possible that PHI translating will end up with
931 // the same value. Consider PHI translating something like:
932 // X = phi [x, bb1], [y, bb2]. PHI translating for bb1 doesn't *need*
933 // to recurse here, pedantically speaking.
935 // If we have a problem phi translating, fall through to the code below
936 // to handle the failure condition.
937 if (getNonLocalPointerDepFromBB(PredPointer, PointeeSize, isLoad, Pred,
939 goto PredTranslationFailure;
942 // Refresh the CacheInfo/Cache pointer so that it isn't invalidated.
943 CacheInfo = &NonLocalPointerDeps[CacheKey];
944 Cache = &CacheInfo->second;
945 NumSortedEntries = Cache->size();
947 // Since we did phi translation, the "Cache" set won't contain all of the
948 // results for the query. This is ok (we can still use it to accelerate
949 // specific block queries) but we can't do the fastpath "return all
950 // results from the set" Clear out the indicator for this.
951 CacheInfo->first = BBSkipFirstBlockPair();
952 SkipFirstBlock = false;
955 PredTranslationFailure:
958 // Refresh the CacheInfo/Cache pointer if it got invalidated.
959 CacheInfo = &NonLocalPointerDeps[CacheKey];
960 Cache = &CacheInfo->second;
961 NumSortedEntries = Cache->size();
964 // Since we did phi translation, the "Cache" set won't contain all of the
965 // results for the query. This is ok (we can still use it to accelerate
966 // specific block queries) but we can't do the fastpath "return all
967 // results from the set" Clear out the indicator for this.
968 CacheInfo->first = BBSkipFirstBlockPair();
970 // If *nothing* works, mark the pointer as being clobbered by the first
971 // instruction in this block.
973 // If this is the magic first block, return this as a clobber of the whole
974 // incoming value. Since we can't phi translate to one of the predecessors,
975 // we have to bail out.
979 for (NonLocalDepInfo::reverse_iterator I = Cache->rbegin(); ; ++I) {
980 assert(I != Cache->rend() && "Didn't find current block??");
981 if (I->getBB() != BB)
984 assert(I->getResult().isNonLocal() &&
985 "Should only be here with transparent block");
986 I->setResult(MemDepResult::getClobber(BB->begin()), Pointer.getAddr());
987 ReverseNonLocalPtrDeps[BB->begin()].insert(CacheKey);
988 Result.push_back(*I);
993 // Okay, we're done now. If we added new values to the cache, re-sort it.
994 SortNonLocalDepInfoCache(*Cache, NumSortedEntries);
995 DEBUG(AssertSorted(*Cache));
999 /// RemoveCachedNonLocalPointerDependencies - If P exists in
1000 /// CachedNonLocalPointerInfo, remove it.
1001 void MemoryDependenceAnalysis::
1002 RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair P) {
1003 CachedNonLocalPointerInfo::iterator It =
1004 NonLocalPointerDeps.find(P);
1005 if (It == NonLocalPointerDeps.end()) return;
1007 // Remove all of the entries in the BB->val map. This involves removing
1008 // instructions from the reverse map.
1009 NonLocalDepInfo &PInfo = It->second.second;
1011 for (unsigned i = 0, e = PInfo.size(); i != e; ++i) {
1012 Instruction *Target = PInfo[i].getResult().getInst();
1013 if (Target == 0) continue; // Ignore non-local dep results.
1014 assert(Target->getParent() == PInfo[i].getBB());
1016 // Eliminating the dirty entry from 'Cache', so update the reverse info.
1017 RemoveFromReverseMap(ReverseNonLocalPtrDeps, Target, P);
1020 // Remove P from NonLocalPointerDeps (which deletes NonLocalDepInfo).
1021 NonLocalPointerDeps.erase(It);
1025 /// invalidateCachedPointerInfo - This method is used to invalidate cached
1026 /// information about the specified pointer, because it may be too
1027 /// conservative in memdep. This is an optional call that can be used when
1028 /// the client detects an equivalence between the pointer and some other
1029 /// value and replaces the other value with ptr. This can make Ptr available
1030 /// in more places that cached info does not necessarily keep.
1031 void MemoryDependenceAnalysis::invalidateCachedPointerInfo(Value *Ptr) {
1032 // If Ptr isn't really a pointer, just ignore it.
1033 if (!isa<PointerType>(Ptr->getType())) return;
1034 // Flush store info for the pointer.
1035 RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(Ptr, false));
1036 // Flush load info for the pointer.
1037 RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(Ptr, true));
1040 /// removeInstruction - Remove an instruction from the dependence analysis,
1041 /// updating the dependence of instructions that previously depended on it.
1042 /// This method attempts to keep the cache coherent using the reverse map.
1043 void MemoryDependenceAnalysis::removeInstruction(Instruction *RemInst) {
1044 // Walk through the Non-local dependencies, removing this one as the value
1045 // for any cached queries.
1046 NonLocalDepMapType::iterator NLDI = NonLocalDeps.find(RemInst);
1047 if (NLDI != NonLocalDeps.end()) {
1048 NonLocalDepInfo &BlockMap = NLDI->second.first;
1049 for (NonLocalDepInfo::iterator DI = BlockMap.begin(), DE = BlockMap.end();
1051 if (Instruction *Inst = DI->getResult().getInst())
1052 RemoveFromReverseMap(ReverseNonLocalDeps, Inst, RemInst);
1053 NonLocalDeps.erase(NLDI);
1056 // If we have a cached local dependence query for this instruction, remove it.
1058 LocalDepMapType::iterator LocalDepEntry = LocalDeps.find(RemInst);
1059 if (LocalDepEntry != LocalDeps.end()) {
1060 // Remove us from DepInst's reverse set now that the local dep info is gone.
1061 if (Instruction *Inst = LocalDepEntry->second.getInst())
1062 RemoveFromReverseMap(ReverseLocalDeps, Inst, RemInst);
1064 // Remove this local dependency info.
1065 LocalDeps.erase(LocalDepEntry);
1068 // If we have any cached pointer dependencies on this instruction, remove
1069 // them. If the instruction has non-pointer type, then it can't be a pointer
1072 // Remove it from both the load info and the store info. The instruction
1073 // can't be in either of these maps if it is non-pointer.
1074 if (isa<PointerType>(RemInst->getType())) {
1075 RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(RemInst, false));
1076 RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(RemInst, true));
1079 // Loop over all of the things that depend on the instruction we're removing.
1081 SmallVector<std::pair<Instruction*, Instruction*>, 8> ReverseDepsToAdd;
1083 // If we find RemInst as a clobber or Def in any of the maps for other values,
1084 // we need to replace its entry with a dirty version of the instruction after
1085 // it. If RemInst is a terminator, we use a null dirty value.
1087 // Using a dirty version of the instruction after RemInst saves having to scan
1088 // the entire block to get to this point.
1089 MemDepResult NewDirtyVal;
1090 if (!RemInst->isTerminator())
1091 NewDirtyVal = MemDepResult::getDirty(++BasicBlock::iterator(RemInst));
1093 ReverseDepMapType::iterator ReverseDepIt = ReverseLocalDeps.find(RemInst);
1094 if (ReverseDepIt != ReverseLocalDeps.end()) {
1095 SmallPtrSet<Instruction*, 4> &ReverseDeps = ReverseDepIt->second;
1096 // RemInst can't be the terminator if it has local stuff depending on it.
1097 assert(!ReverseDeps.empty() && !isa<TerminatorInst>(RemInst) &&
1098 "Nothing can locally depend on a terminator");
1100 for (SmallPtrSet<Instruction*, 4>::iterator I = ReverseDeps.begin(),
1101 E = ReverseDeps.end(); I != E; ++I) {
1102 Instruction *InstDependingOnRemInst = *I;
1103 assert(InstDependingOnRemInst != RemInst &&
1104 "Already removed our local dep info");
1106 LocalDeps[InstDependingOnRemInst] = NewDirtyVal;
1108 // Make sure to remember that new things depend on NewDepInst.
1109 assert(NewDirtyVal.getInst() && "There is no way something else can have "
1110 "a local dep on this if it is a terminator!");
1111 ReverseDepsToAdd.push_back(std::make_pair(NewDirtyVal.getInst(),
1112 InstDependingOnRemInst));
1115 ReverseLocalDeps.erase(ReverseDepIt);
1117 // Add new reverse deps after scanning the set, to avoid invalidating the
1118 // 'ReverseDeps' reference.
1119 while (!ReverseDepsToAdd.empty()) {
1120 ReverseLocalDeps[ReverseDepsToAdd.back().first]
1121 .insert(ReverseDepsToAdd.back().second);
1122 ReverseDepsToAdd.pop_back();
1126 ReverseDepIt = ReverseNonLocalDeps.find(RemInst);
1127 if (ReverseDepIt != ReverseNonLocalDeps.end()) {
1128 SmallPtrSet<Instruction*, 4> &Set = ReverseDepIt->second;
1129 for (SmallPtrSet<Instruction*, 4>::iterator I = Set.begin(), E = Set.end();
1131 assert(*I != RemInst && "Already removed NonLocalDep info for RemInst");
1133 PerInstNLInfo &INLD = NonLocalDeps[*I];
1134 // The information is now dirty!
1137 for (NonLocalDepInfo::iterator DI = INLD.first.begin(),
1138 DE = INLD.first.end(); DI != DE; ++DI) {
1139 if (DI->getResult().getInst() != RemInst) continue;
1141 // Convert to a dirty entry for the subsequent instruction.
1142 DI->setResult(NewDirtyVal, DI->getAddress());
1144 if (Instruction *NextI = NewDirtyVal.getInst())
1145 ReverseDepsToAdd.push_back(std::make_pair(NextI, *I));
1149 ReverseNonLocalDeps.erase(ReverseDepIt);
1151 // Add new reverse deps after scanning the set, to avoid invalidating 'Set'
1152 while (!ReverseDepsToAdd.empty()) {
1153 ReverseNonLocalDeps[ReverseDepsToAdd.back().first]
1154 .insert(ReverseDepsToAdd.back().second);
1155 ReverseDepsToAdd.pop_back();
1159 // If the instruction is in ReverseNonLocalPtrDeps then it appears as a
1160 // value in the NonLocalPointerDeps info.
1161 ReverseNonLocalPtrDepTy::iterator ReversePtrDepIt =
1162 ReverseNonLocalPtrDeps.find(RemInst);
1163 if (ReversePtrDepIt != ReverseNonLocalPtrDeps.end()) {
1164 SmallPtrSet<ValueIsLoadPair, 4> &Set = ReversePtrDepIt->second;
1165 SmallVector<std::pair<Instruction*, ValueIsLoadPair>,8> ReversePtrDepsToAdd;
1167 for (SmallPtrSet<ValueIsLoadPair, 4>::iterator I = Set.begin(),
1168 E = Set.end(); I != E; ++I) {
1169 ValueIsLoadPair P = *I;
1170 assert(P.getPointer() != RemInst &&
1171 "Already removed NonLocalPointerDeps info for RemInst");
1173 NonLocalDepInfo &NLPDI = NonLocalPointerDeps[P].second;
1175 // The cache is not valid for any specific block anymore.
1176 NonLocalPointerDeps[P].first = BBSkipFirstBlockPair();
1178 // Update any entries for RemInst to use the instruction after it.
1179 for (NonLocalDepInfo::iterator DI = NLPDI.begin(), DE = NLPDI.end();
1181 if (DI->getResult().getInst() != RemInst) continue;
1183 // Convert to a dirty entry for the subsequent instruction.
1184 DI->setResult(NewDirtyVal, DI->getAddress());
1186 if (Instruction *NewDirtyInst = NewDirtyVal.getInst())
1187 ReversePtrDepsToAdd.push_back(std::make_pair(NewDirtyInst, P));
1190 // Re-sort the NonLocalDepInfo. Changing the dirty entry to its
1191 // subsequent value may invalidate the sortedness.
1192 std::sort(NLPDI.begin(), NLPDI.end());
1195 ReverseNonLocalPtrDeps.erase(ReversePtrDepIt);
1197 while (!ReversePtrDepsToAdd.empty()) {
1198 ReverseNonLocalPtrDeps[ReversePtrDepsToAdd.back().first]
1199 .insert(ReversePtrDepsToAdd.back().second);
1200 ReversePtrDepsToAdd.pop_back();
1205 assert(!NonLocalDeps.count(RemInst) && "RemInst got reinserted?");
1206 AA->deleteValue(RemInst);
1207 DEBUG(verifyRemoved(RemInst));
1209 /// verifyRemoved - Verify that the specified instruction does not occur
1210 /// in our internal data structures.
1211 void MemoryDependenceAnalysis::verifyRemoved(Instruction *D) const {
1212 for (LocalDepMapType::const_iterator I = LocalDeps.begin(),
1213 E = LocalDeps.end(); I != E; ++I) {
1214 assert(I->first != D && "Inst occurs in data structures");
1215 assert(I->second.getInst() != D &&
1216 "Inst occurs in data structures");
1219 for (CachedNonLocalPointerInfo::const_iterator I =NonLocalPointerDeps.begin(),
1220 E = NonLocalPointerDeps.end(); I != E; ++I) {
1221 assert(I->first.getPointer() != D && "Inst occurs in NLPD map key");
1222 const NonLocalDepInfo &Val = I->second.second;
1223 for (NonLocalDepInfo::const_iterator II = Val.begin(), E = Val.end();
1225 assert(II->getResult().getInst() != D && "Inst occurs as NLPD value");
1228 for (NonLocalDepMapType::const_iterator I = NonLocalDeps.begin(),
1229 E = NonLocalDeps.end(); I != E; ++I) {
1230 assert(I->first != D && "Inst occurs in data structures");
1231 const PerInstNLInfo &INLD = I->second;
1232 for (NonLocalDepInfo::const_iterator II = INLD.first.begin(),
1233 EE = INLD.first.end(); II != EE; ++II)
1234 assert(II->getResult().getInst() != D && "Inst occurs in data structures");
1237 for (ReverseDepMapType::const_iterator I = ReverseLocalDeps.begin(),
1238 E = ReverseLocalDeps.end(); I != E; ++I) {
1239 assert(I->first != D && "Inst occurs in data structures");
1240 for (SmallPtrSet<Instruction*, 4>::const_iterator II = I->second.begin(),
1241 EE = I->second.end(); II != EE; ++II)
1242 assert(*II != D && "Inst occurs in data structures");
1245 for (ReverseDepMapType::const_iterator I = ReverseNonLocalDeps.begin(),
1246 E = ReverseNonLocalDeps.end();
1248 assert(I->first != D && "Inst occurs in data structures");
1249 for (SmallPtrSet<Instruction*, 4>::const_iterator II = I->second.begin(),
1250 EE = I->second.end(); II != EE; ++II)
1251 assert(*II != D && "Inst occurs in data structures");
1254 for (ReverseNonLocalPtrDepTy::const_iterator
1255 I = ReverseNonLocalPtrDeps.begin(),
1256 E = ReverseNonLocalPtrDeps.end(); I != E; ++I) {
1257 assert(I->first != D && "Inst occurs in rev NLPD map");
1259 for (SmallPtrSet<ValueIsLoadPair, 4>::const_iterator II = I->second.begin(),
1260 E = I->second.end(); II != E; ++II)
1261 assert(*II != ValueIsLoadPair(D, false) &&
1262 *II != ValueIsLoadPair(D, true) &&
1263 "Inst occurs in ReverseNonLocalPtrDeps map");