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/LLVMContext.h"
23 #include "llvm/Analysis/AliasAnalysis.h"
24 #include "llvm/Analysis/Dominators.h"
25 #include "llvm/Analysis/InstructionSimplify.h"
26 #include "llvm/Analysis/MemoryBuiltins.h"
27 #include "llvm/Analysis/PHITransAddr.h"
28 #include "llvm/ADT/Statistic.h"
29 #include "llvm/ADT/STLExtras.h"
30 #include "llvm/Support/PredIteratorCache.h"
31 #include "llvm/Support/Debug.h"
34 STATISTIC(NumCacheNonLocal, "Number of fully cached non-local responses");
35 STATISTIC(NumCacheDirtyNonLocal, "Number of dirty cached non-local responses");
36 STATISTIC(NumUncacheNonLocal, "Number of uncached non-local responses");
38 STATISTIC(NumCacheNonLocalPtr,
39 "Number of fully cached non-local ptr responses");
40 STATISTIC(NumCacheDirtyNonLocalPtr,
41 "Number of cached, but dirty, non-local ptr responses");
42 STATISTIC(NumUncacheNonLocalPtr,
43 "Number of uncached non-local ptr responses");
44 STATISTIC(NumCacheCompleteNonLocalPtr,
45 "Number of block queries that were completely cached");
47 char MemoryDependenceAnalysis::ID = 0;
49 // Register this pass...
50 INITIALIZE_PASS(MemoryDependenceAnalysis, "memdep",
51 "Memory Dependence Analysis", false, true);
53 MemoryDependenceAnalysis::MemoryDependenceAnalysis()
54 : FunctionPass(ID), PredCache(0) {
56 MemoryDependenceAnalysis::~MemoryDependenceAnalysis() {
59 /// Clean up memory in between runs
60 void MemoryDependenceAnalysis::releaseMemory() {
63 NonLocalPointerDeps.clear();
64 ReverseLocalDeps.clear();
65 ReverseNonLocalDeps.clear();
66 ReverseNonLocalPtrDeps.clear();
72 /// getAnalysisUsage - Does not modify anything. It uses Alias Analysis.
74 void MemoryDependenceAnalysis::getAnalysisUsage(AnalysisUsage &AU) const {
76 AU.addRequiredTransitive<AliasAnalysis>();
79 bool MemoryDependenceAnalysis::runOnFunction(Function &) {
80 AA = &getAnalysis<AliasAnalysis>();
82 PredCache.reset(new PredIteratorCache());
86 /// RemoveFromReverseMap - This is a helper function that removes Val from
87 /// 'Inst's set in ReverseMap. If the set becomes empty, remove Inst's entry.
88 template <typename KeyTy>
89 static void RemoveFromReverseMap(DenseMap<Instruction*,
90 SmallPtrSet<KeyTy, 4> > &ReverseMap,
91 Instruction *Inst, KeyTy Val) {
92 typename DenseMap<Instruction*, SmallPtrSet<KeyTy, 4> >::iterator
93 InstIt = ReverseMap.find(Inst);
94 assert(InstIt != ReverseMap.end() && "Reverse map out of sync?");
95 bool Found = InstIt->second.erase(Val);
96 assert(Found && "Invalid reverse map!"); Found=Found;
97 if (InstIt->second.empty())
98 ReverseMap.erase(InstIt);
102 /// getCallSiteDependencyFrom - Private helper for finding the local
103 /// dependencies of a call site.
104 MemDepResult MemoryDependenceAnalysis::
105 getCallSiteDependencyFrom(CallSite CS, bool isReadOnlyCall,
106 BasicBlock::iterator ScanIt, BasicBlock *BB) {
107 // Walk backwards through the block, looking for dependencies
108 while (ScanIt != BB->begin()) {
109 Instruction *Inst = --ScanIt;
111 // If this inst is a memory op, get the pointer it accessed
112 AliasAnalysis::Location Loc;
113 if (StoreInst *S = dyn_cast<StoreInst>(Inst)) {
114 Loc = AliasAnalysis::Location(S->getPointerOperand(),
115 AA->getTypeStoreSize(S->getValueOperand()
117 S->getMetadata(LLVMContext::MD_tbaa));
118 } else if (VAArgInst *V = dyn_cast<VAArgInst>(Inst)) {
119 Loc = AliasAnalysis::Location(V->getPointerOperand(),
120 AA->getTypeStoreSize(V->getType()),
121 V->getMetadata(LLVMContext::MD_tbaa));
122 } else if (const CallInst *CI = isFreeCall(Inst)) {
123 // calls to free() erase the entire structure
124 Loc = AliasAnalysis::Location(CI->getArgOperand(0));
125 } else if (CallSite InstCS = cast<Value>(Inst)) {
126 // Debug intrinsics don't cause dependences.
127 if (isa<DbgInfoIntrinsic>(Inst)) continue;
128 // If these two calls do not interfere, look past it.
129 switch (AA->getModRefInfo(CS, InstCS)) {
130 case AliasAnalysis::NoModRef:
131 // If the two calls are the same, return InstCS as a Def, so that
132 // CS can be found redundant and eliminated.
133 if (isReadOnlyCall && InstCS.onlyReadsMemory() &&
134 CS.getInstruction()->isIdenticalToWhenDefined(Inst))
135 return MemDepResult::getDef(Inst);
137 // Otherwise if the two calls don't interact (e.g. InstCS is readnone)
141 return MemDepResult::getClobber(Inst);
144 // Non-memory instruction.
148 if (AA->getModRefInfo(CS, Loc) != AliasAnalysis::NoModRef)
149 return MemDepResult::getClobber(Inst);
152 // No dependence found. If this is the entry block of the function, it is a
153 // clobber, otherwise it is non-local.
154 if (BB != &BB->getParent()->getEntryBlock())
155 return MemDepResult::getNonLocal();
156 return MemDepResult::getClobber(ScanIt);
159 /// getPointerDependencyFrom - Return the instruction on which a memory
160 /// location depends. If isLoad is true, this routine ignore may-aliases with
161 /// read-only operations.
162 MemDepResult MemoryDependenceAnalysis::
163 getPointerDependencyFrom(const AliasAnalysis::Location &MemLoc, bool isLoad,
164 BasicBlock::iterator ScanIt, BasicBlock *BB) {
166 Value *InvariantTag = 0;
168 // Walk backwards through the basic block, looking for dependencies.
169 while (ScanIt != BB->begin()) {
170 Instruction *Inst = --ScanIt;
172 // If we're in an invariant region, no dependencies can be found before
173 // we pass an invariant-begin marker.
174 if (InvariantTag == Inst) {
179 if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(Inst)) {
180 // Debug intrinsics don't (and can't) cause dependences.
181 if (isa<DbgInfoIntrinsic>(II)) continue;
183 // If we pass an invariant-end marker, then we've just entered an
184 // invariant region and can start ignoring dependencies.
185 if (II->getIntrinsicID() == Intrinsic::invariant_end) {
186 // FIXME: This only considers queries directly on the invariant-tagged
187 // pointer, not on query pointers that are indexed off of them. It'd
188 // be nice to handle that at some point.
189 AliasAnalysis::AliasResult R =
190 AA->alias(AliasAnalysis::Location(II->getArgOperand(2)), MemLoc);
191 if (R == AliasAnalysis::MustAlias)
192 InvariantTag = II->getArgOperand(0);
197 // If we reach a lifetime begin or end marker, then the query ends here
198 // because the value is undefined.
199 if (II->getIntrinsicID() == Intrinsic::lifetime_start) {
200 // FIXME: This only considers queries directly on the invariant-tagged
201 // pointer, not on query pointers that are indexed off of them. It'd
202 // be nice to handle that at some point.
203 AliasAnalysis::AliasResult R =
204 AA->alias(AliasAnalysis::Location(II->getArgOperand(1)), MemLoc);
205 if (R == AliasAnalysis::MustAlias)
206 return MemDepResult::getDef(II);
211 // If we're querying on a load and we're in an invariant region, we're done
212 // at this point. Nothing a load depends on can live in an invariant region.
214 // FIXME: this will prevent us from returning load/load must-aliases, so GVN
215 // won't remove redundant loads.
216 if (isLoad && InvariantTag) continue;
218 // Values depend on loads if the pointers are must aliased. This means that
219 // a load depends on another must aliased load from the same value.
220 if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) {
221 Value *Pointer = LI->getPointerOperand();
222 uint64_t PointerSize = AA->getTypeStoreSize(LI->getType());
223 MDNode *TBAATag = LI->getMetadata(LLVMContext::MD_tbaa);
225 // If we found a pointer, check if it could be the same as our pointer.
226 AliasAnalysis::AliasResult R =
227 AA->alias(AliasAnalysis::Location(Pointer, PointerSize, TBAATag),
229 if (R == AliasAnalysis::NoAlias)
232 // May-alias loads don't depend on each other without a dependence.
233 if (isLoad && R == AliasAnalysis::MayAlias)
235 // Stores depend on may and must aliased loads, loads depend on must-alias
237 return MemDepResult::getDef(Inst);
240 if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
241 // There can't be stores to the value we care about inside an
243 if (InvariantTag) continue;
245 // If alias analysis can tell that this store is guaranteed to not modify
246 // the query pointer, ignore it. Use getModRefInfo to handle cases where
247 // the query pointer points to constant memory etc.
248 if (AA->getModRefInfo(SI, MemLoc) == AliasAnalysis::NoModRef)
251 // Ok, this store might clobber the query pointer. Check to see if it is
252 // a must alias: in this case, we want to return this as a def.
253 Value *Pointer = SI->getPointerOperand();
254 uint64_t PointerSize = AA->getTypeStoreSize(SI->getOperand(0)->getType());
255 MDNode *TBAATag = SI->getMetadata(LLVMContext::MD_tbaa);
257 // If we found a pointer, check if it could be the same as our pointer.
258 AliasAnalysis::AliasResult R =
259 AA->alias(AliasAnalysis::Location(Pointer, PointerSize, TBAATag),
262 if (R == AliasAnalysis::NoAlias)
264 if (R == AliasAnalysis::MayAlias)
265 return MemDepResult::getClobber(Inst);
266 return MemDepResult::getDef(Inst);
269 // If this is an allocation, and if we know that the accessed pointer is to
270 // the allocation, return Def. This means that there is no dependence and
271 // the access can be optimized based on that. For example, a load could
273 // Note: Only determine this to be a malloc if Inst is the malloc call, not
274 // a subsequent bitcast of the malloc call result. There can be stores to
275 // the malloced memory between the malloc call and its bitcast uses, and we
276 // need to continue scanning until the malloc call.
277 if (isa<AllocaInst>(Inst) ||
278 (isa<CallInst>(Inst) && extractMallocCall(Inst))) {
279 const Value *AccessPtr = MemLoc.Ptr->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, MemLoc)) {
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();
338 AliasAnalysis::Location MemLoc;
341 if (BasicBlock::iterator(QueryInst) == QueryParent->begin()) {
342 // No dependence found. If this is the entry block of the function, it is a
343 // clobber, otherwise it is non-local.
344 if (QueryParent != &QueryParent->getParent()->getEntryBlock())
345 LocalCache = MemDepResult::getNonLocal();
347 LocalCache = MemDepResult::getClobber(QueryInst);
348 } else if (StoreInst *SI = dyn_cast<StoreInst>(QueryInst)) {
349 // If this is a volatile store, don't mess around with it. Just return the
350 // previous instruction as a clobber.
351 if (SI->isVolatile())
352 LocalCache = MemDepResult::getClobber(--BasicBlock::iterator(ScanPos));
354 MemLoc = AliasAnalysis::Location(SI->getPointerOperand(),
355 AA->getTypeStoreSize(SI->getOperand(0)
357 SI->getMetadata(LLVMContext::MD_tbaa));
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 MemLoc = AliasAnalysis::Location(LI->getPointerOperand(),
365 AA->getTypeStoreSize(LI->getType()),
366 LI->getMetadata(LLVMContext::MD_tbaa));
367 } else if (const CallInst *CI = isFreeCall(QueryInst)) {
368 // calls to free() erase the entire structure, not just a field.
369 MemLoc = AliasAnalysis::Location(CI->getArgOperand(0));
370 } else if (isa<CallInst>(QueryInst) || isa<InvokeInst>(QueryInst)) {
371 int IntrinsicID = 0; // Intrinsic IDs start at 1.
372 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 MemLoc = AliasAnalysis::Location(II->getArgOperand(1),
381 cast<ConstantInt>(II->getArgOperand(0))
383 II->getMetadata(LLVMContext::MD_tbaa));
385 case Intrinsic::invariant_end:
386 MemLoc = AliasAnalysis::Location(II->getArgOperand(2),
387 cast<ConstantInt>(II->getArgOperand(1))
389 II->getMetadata(LLVMContext::MD_tbaa));
392 CallSite QueryCS(QueryInst);
393 bool isReadOnly = AA->onlyReadsMemory(QueryCS);
394 LocalCache = getCallSiteDependencyFrom(QueryCS, isReadOnly, ScanPos,
399 // Non-memory instruction.
400 LocalCache = MemDepResult::getClobber(--BasicBlock::iterator(ScanPos));
403 // If we need to do a pointer scan, make it happen.
405 bool isLoad = !QueryInst->mayWriteToMemory();
406 if (IntrinsicInst *II = dyn_cast<MemoryUseIntrinsic>(QueryInst)) {
407 isLoad |= II->getIntrinsicID() == Intrinsic::lifetime_end;
409 LocalCache = getPointerDependencyFrom(MemLoc, isLoad, ScanPos,
413 // Remember the result!
414 if (Instruction *I = LocalCache.getInst())
415 ReverseLocalDeps[I].insert(QueryInst);
421 /// AssertSorted - This method is used when -debug is specified to verify that
422 /// cache arrays are properly kept sorted.
423 static void AssertSorted(MemoryDependenceAnalysis::NonLocalDepInfo &Cache,
425 if (Count == -1) Count = Cache.size();
426 if (Count == 0) return;
428 for (unsigned i = 1; i != unsigned(Count); ++i)
429 assert(!(Cache[i] < Cache[i-1]) && "Cache isn't sorted!");
433 /// getNonLocalCallDependency - Perform a full dependency query for the
434 /// specified call, returning the set of blocks that the value is
435 /// potentially live across. The returned set of results will include a
436 /// "NonLocal" result for all blocks where the value is live across.
438 /// This method assumes the instruction returns a "NonLocal" dependency
439 /// within its own block.
441 /// This returns a reference to an internal data structure that may be
442 /// invalidated on the next non-local query or when an instruction is
443 /// removed. Clients must copy this data if they want it around longer than
445 const MemoryDependenceAnalysis::NonLocalDepInfo &
446 MemoryDependenceAnalysis::getNonLocalCallDependency(CallSite QueryCS) {
447 assert(getDependency(QueryCS.getInstruction()).isNonLocal() &&
448 "getNonLocalCallDependency should only be used on calls with non-local deps!");
449 PerInstNLInfo &CacheP = NonLocalDeps[QueryCS.getInstruction()];
450 NonLocalDepInfo &Cache = CacheP.first;
452 /// DirtyBlocks - This is the set of blocks that need to be recomputed. In
453 /// the cached case, this can happen due to instructions being deleted etc. In
454 /// the uncached case, this starts out as the set of predecessors we care
456 SmallVector<BasicBlock*, 32> DirtyBlocks;
458 if (!Cache.empty()) {
459 // Okay, we have a cache entry. If we know it is not dirty, just return it
460 // with no computation.
461 if (!CacheP.second) {
466 // If we already have a partially computed set of results, scan them to
467 // determine what is dirty, seeding our initial DirtyBlocks worklist.
468 for (NonLocalDepInfo::iterator I = Cache.begin(), E = Cache.end();
470 if (I->getResult().isDirty())
471 DirtyBlocks.push_back(I->getBB());
473 // Sort the cache so that we can do fast binary search lookups below.
474 std::sort(Cache.begin(), Cache.end());
476 ++NumCacheDirtyNonLocal;
477 //cerr << "CACHED CASE: " << DirtyBlocks.size() << " dirty: "
478 // << Cache.size() << " cached: " << *QueryInst;
480 // Seed DirtyBlocks with each of the preds of QueryInst's block.
481 BasicBlock *QueryBB = QueryCS.getInstruction()->getParent();
482 for (BasicBlock **PI = PredCache->GetPreds(QueryBB); *PI; ++PI)
483 DirtyBlocks.push_back(*PI);
484 ++NumUncacheNonLocal;
487 // isReadonlyCall - If this is a read-only call, we can be more aggressive.
488 bool isReadonlyCall = AA->onlyReadsMemory(QueryCS);
490 SmallPtrSet<BasicBlock*, 64> Visited;
492 unsigned NumSortedEntries = Cache.size();
493 DEBUG(AssertSorted(Cache));
495 // Iterate while we still have blocks to update.
496 while (!DirtyBlocks.empty()) {
497 BasicBlock *DirtyBB = DirtyBlocks.back();
498 DirtyBlocks.pop_back();
500 // Already processed this block?
501 if (!Visited.insert(DirtyBB))
504 // Do a binary search to see if we already have an entry for this block in
505 // the cache set. If so, find it.
506 DEBUG(AssertSorted(Cache, NumSortedEntries));
507 NonLocalDepInfo::iterator Entry =
508 std::upper_bound(Cache.begin(), Cache.begin()+NumSortedEntries,
509 NonLocalDepEntry(DirtyBB));
510 if (Entry != Cache.begin() && prior(Entry)->getBB() == DirtyBB)
513 NonLocalDepEntry *ExistingResult = 0;
514 if (Entry != Cache.begin()+NumSortedEntries &&
515 Entry->getBB() == DirtyBB) {
516 // If we already have an entry, and if it isn't already dirty, the block
518 if (!Entry->getResult().isDirty())
521 // Otherwise, remember this slot so we can update the value.
522 ExistingResult = &*Entry;
525 // If the dirty entry has a pointer, start scanning from it so we don't have
526 // to rescan the entire block.
527 BasicBlock::iterator ScanPos = DirtyBB->end();
528 if (ExistingResult) {
529 if (Instruction *Inst = ExistingResult->getResult().getInst()) {
531 // We're removing QueryInst's use of Inst.
532 RemoveFromReverseMap(ReverseNonLocalDeps, Inst,
533 QueryCS.getInstruction());
537 // Find out if this block has a local dependency for QueryInst.
540 if (ScanPos != DirtyBB->begin()) {
541 Dep = getCallSiteDependencyFrom(QueryCS, isReadonlyCall,ScanPos, DirtyBB);
542 } else if (DirtyBB != &DirtyBB->getParent()->getEntryBlock()) {
543 // No dependence found. If this is the entry block of the function, it is
544 // a clobber, otherwise it is non-local.
545 Dep = MemDepResult::getNonLocal();
547 Dep = MemDepResult::getClobber(ScanPos);
550 // If we had a dirty entry for the block, update it. Otherwise, just add
553 ExistingResult->setResult(Dep);
555 Cache.push_back(NonLocalDepEntry(DirtyBB, Dep));
557 // If the block has a dependency (i.e. it isn't completely transparent to
558 // the value), remember the association!
559 if (!Dep.isNonLocal()) {
560 // Keep the ReverseNonLocalDeps map up to date so we can efficiently
561 // update this when we remove instructions.
562 if (Instruction *Inst = Dep.getInst())
563 ReverseNonLocalDeps[Inst].insert(QueryCS.getInstruction());
566 // If the block *is* completely transparent to the load, we need to check
567 // the predecessors of this block. Add them to our worklist.
568 for (BasicBlock **PI = PredCache->GetPreds(DirtyBB); *PI; ++PI)
569 DirtyBlocks.push_back(*PI);
576 /// getNonLocalPointerDependency - Perform a full dependency query for an
577 /// access to the specified (non-volatile) memory location, returning the
578 /// set of instructions that either define or clobber the value.
580 /// This method assumes the pointer has a "NonLocal" dependency within its
583 void MemoryDependenceAnalysis::
584 getNonLocalPointerDependency(const AliasAnalysis::Location &Loc, bool isLoad,
586 SmallVectorImpl<NonLocalDepResult> &Result) {
587 assert(Loc.Ptr->getType()->isPointerTy() &&
588 "Can't get pointer deps of a non-pointer!");
591 PHITransAddr Address(const_cast<Value *>(Loc.Ptr), 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, Loc, isLoad, FromBB,
599 Result, Visited, true))
602 Result.push_back(NonLocalDepResult(FromBB,
603 MemDepResult::getClobber(FromBB->begin()),
604 const_cast<Value *>(Loc.Ptr)));
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(const AliasAnalysis::Location &Loc,
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(Loc.Ptr, isLoad);
647 RemoveFromReverseMap(ReverseNonLocalPtrDeps, ScanPos, CacheKey);
649 ++NumUncacheNonLocalPtr;
652 // Scan the block for the dependency.
653 MemDepResult Dep = getPointerDependencyFrom(Loc, isLoad, ScanPos, BB);
655 // If we had a dirty entry for the block, update it. Otherwise, just add
658 ExistingResult->setResult(Dep);
660 Cache->push_back(NonLocalDepEntry(BB, Dep));
662 // If the block has a dependency (i.e. it isn't completely transparent to
663 // the value), remember the reverse association because we just added it
665 if (Dep.isNonLocal())
668 // Keep the ReverseNonLocalPtrDeps map up to date so we can efficiently
669 // update MemDep when we remove instructions.
670 Instruction *Inst = Dep.getInst();
671 assert(Inst && "Didn't depend on anything?");
672 ValueIsLoadPair CacheKey(Loc.Ptr, isLoad);
673 ReverseNonLocalPtrDeps[Inst].insert(CacheKey);
677 /// SortNonLocalDepInfoCache - Sort the a NonLocalDepInfo cache, given a certain
678 /// number of elements in the array that are already properly ordered. This is
679 /// optimized for the case when only a few entries are added.
681 SortNonLocalDepInfoCache(MemoryDependenceAnalysis::NonLocalDepInfo &Cache,
682 unsigned NumSortedEntries) {
683 switch (Cache.size() - NumSortedEntries) {
685 // done, no new entries.
688 // Two new entries, insert the last one into place.
689 NonLocalDepEntry Val = Cache.back();
691 MemoryDependenceAnalysis::NonLocalDepInfo::iterator Entry =
692 std::upper_bound(Cache.begin(), Cache.end()-1, Val);
693 Cache.insert(Entry, Val);
697 // One new entry, Just insert the new value at the appropriate position.
698 if (Cache.size() != 1) {
699 NonLocalDepEntry Val = Cache.back();
701 MemoryDependenceAnalysis::NonLocalDepInfo::iterator Entry =
702 std::upper_bound(Cache.begin(), Cache.end(), Val);
703 Cache.insert(Entry, Val);
707 // Added many values, do a full scale sort.
708 std::sort(Cache.begin(), Cache.end());
713 /// getNonLocalPointerDepFromBB - Perform a dependency query based on
714 /// pointer/pointeesize starting at the end of StartBB. Add any clobber/def
715 /// results to the results vector and keep track of which blocks are visited in
718 /// This has special behavior for the first block queries (when SkipFirstBlock
719 /// is true). In this special case, it ignores the contents of the specified
720 /// block and starts returning dependence info for its predecessors.
722 /// This function returns false on success, or true to indicate that it could
723 /// not compute dependence information for some reason. This should be treated
724 /// as a clobber dependence on the first instruction in the predecessor block.
725 bool MemoryDependenceAnalysis::
726 getNonLocalPointerDepFromBB(const PHITransAddr &Pointer,
727 const AliasAnalysis::Location &Loc,
728 bool isLoad, BasicBlock *StartBB,
729 SmallVectorImpl<NonLocalDepResult> &Result,
730 DenseMap<BasicBlock*, Value*> &Visited,
731 bool SkipFirstBlock) {
733 // Look up the cached info for Pointer.
734 ValueIsLoadPair CacheKey(Pointer.getAddr(), isLoad);
735 NonLocalPointerInfo *CacheInfo = &NonLocalPointerDeps[CacheKey];
737 // If this query's TBAATag is inconsistent with the cached one, discard the
738 // tag and restart the query.
739 if (CacheInfo->TBAATag != Loc.TBAATag) {
740 CacheInfo->TBAATag = 0;
741 NonLocalPointerDeps.erase(CacheKey);
742 return getNonLocalPointerDepFromBB(Pointer, Loc.getWithoutTBAATag(),
743 isLoad, StartBB, Result, Visited,
747 NonLocalDepInfo *Cache = &CacheInfo->NonLocalDeps;
749 // If we have valid cached information for exactly the block we are
750 // investigating, just return it with no recomputation.
751 if (CacheInfo->Pair == BBSkipFirstBlockPair(StartBB, SkipFirstBlock)) {
752 // We have a fully cached result for this query then we can just return the
753 // cached results and populate the visited set. However, we have to verify
754 // that we don't already have conflicting results for these blocks. Check
755 // to ensure that if a block in the results set is in the visited set that
756 // it was for the same pointer query.
757 if (!Visited.empty()) {
758 for (NonLocalDepInfo::iterator I = Cache->begin(), E = Cache->end();
760 DenseMap<BasicBlock*, Value*>::iterator VI = Visited.find(I->getBB());
761 if (VI == Visited.end() || VI->second == Pointer.getAddr())
764 // We have a pointer mismatch in a block. Just return clobber, saying
765 // that something was clobbered in this result. We could also do a
766 // non-fully cached query, but there is little point in doing this.
771 Value *Addr = Pointer.getAddr();
772 for (NonLocalDepInfo::iterator I = Cache->begin(), E = Cache->end();
774 Visited.insert(std::make_pair(I->getBB(), Addr));
775 if (!I->getResult().isNonLocal())
776 Result.push_back(NonLocalDepResult(I->getBB(), I->getResult(), Addr));
778 ++NumCacheCompleteNonLocalPtr;
782 // Otherwise, either this is a new block, a block with an invalid cache
783 // pointer or one that we're about to invalidate by putting more info into it
784 // than its valid cache info. If empty, the result will be valid cache info,
785 // otherwise it isn't.
787 CacheInfo->Pair = BBSkipFirstBlockPair(StartBB, SkipFirstBlock);
789 CacheInfo->Pair = BBSkipFirstBlockPair();
790 CacheInfo->TBAATag = 0;
793 SmallVector<BasicBlock*, 32> Worklist;
794 Worklist.push_back(StartBB);
796 // Keep track of the entries that we know are sorted. Previously cached
797 // entries will all be sorted. The entries we add we only sort on demand (we
798 // don't insert every element into its sorted position). We know that we
799 // won't get any reuse from currently inserted values, because we don't
800 // revisit blocks after we insert info for them.
801 unsigned NumSortedEntries = Cache->size();
802 DEBUG(AssertSorted(*Cache));
804 while (!Worklist.empty()) {
805 BasicBlock *BB = Worklist.pop_back_val();
807 // Skip the first block if we have it.
808 if (!SkipFirstBlock) {
809 // Analyze the dependency of *Pointer in FromBB. See if we already have
811 assert(Visited.count(BB) && "Should check 'visited' before adding to WL");
813 // Get the dependency info for Pointer in BB. If we have cached
814 // information, we will use it, otherwise we compute it.
815 DEBUG(AssertSorted(*Cache, NumSortedEntries));
816 MemDepResult Dep = GetNonLocalInfoForBlock(Loc, isLoad, BB, Cache,
819 // If we got a Def or Clobber, add this to the list of results.
820 if (!Dep.isNonLocal()) {
821 Result.push_back(NonLocalDepResult(BB, Dep, Pointer.getAddr()));
826 // If 'Pointer' is an instruction defined in this block, then we need to do
827 // phi translation to change it into a value live in the predecessor block.
828 // If not, we just add the predecessors to the worklist and scan them with
830 if (!Pointer.NeedsPHITranslationFromBlock(BB)) {
831 SkipFirstBlock = false;
832 for (BasicBlock **PI = PredCache->GetPreds(BB); *PI; ++PI) {
833 // Verify that we haven't looked at this block yet.
834 std::pair<DenseMap<BasicBlock*,Value*>::iterator, bool>
835 InsertRes = Visited.insert(std::make_pair(*PI, Pointer.getAddr()));
836 if (InsertRes.second) {
837 // First time we've looked at *PI.
838 Worklist.push_back(*PI);
842 // If we have seen this block before, but it was with a different
843 // pointer then we have a phi translation failure and we have to treat
844 // this as a clobber.
845 if (InsertRes.first->second != Pointer.getAddr())
846 goto PredTranslationFailure;
851 // We do need to do phi translation, if we know ahead of time we can't phi
852 // translate this value, don't even try.
853 if (!Pointer.IsPotentiallyPHITranslatable())
854 goto PredTranslationFailure;
856 // We may have added values to the cache list before this PHI translation.
857 // If so, we haven't done anything to ensure that the cache remains sorted.
858 // Sort it now (if needed) so that recursive invocations of
859 // getNonLocalPointerDepFromBB and other routines that could reuse the cache
860 // value will only see properly sorted cache arrays.
861 if (Cache && NumSortedEntries != Cache->size()) {
862 SortNonLocalDepInfoCache(*Cache, NumSortedEntries);
863 NumSortedEntries = Cache->size();
867 for (BasicBlock **PI = PredCache->GetPreds(BB); *PI; ++PI) {
868 BasicBlock *Pred = *PI;
870 // Get the PHI translated pointer in this predecessor. This can fail if
871 // not translatable, in which case the getAddr() returns null.
872 PHITransAddr PredPointer(Pointer);
873 PredPointer.PHITranslateValue(BB, Pred, 0);
875 Value *PredPtrVal = PredPointer.getAddr();
877 // Check to see if we have already visited this pred block with another
878 // pointer. If so, we can't do this lookup. This failure can occur
879 // with PHI translation when a critical edge exists and the PHI node in
880 // the successor translates to a pointer value different than the
881 // pointer the block was first analyzed with.
882 std::pair<DenseMap<BasicBlock*,Value*>::iterator, bool>
883 InsertRes = Visited.insert(std::make_pair(Pred, PredPtrVal));
885 if (!InsertRes.second) {
886 // If the predecessor was visited with PredPtr, then we already did
887 // the analysis and can ignore it.
888 if (InsertRes.first->second == PredPtrVal)
891 // Otherwise, the block was previously analyzed with a different
892 // pointer. We can't represent the result of this case, so we just
893 // treat this as a phi translation failure.
894 goto PredTranslationFailure;
897 // If PHI translation was unable to find an available pointer in this
898 // predecessor, then we have to assume that the pointer is clobbered in
899 // that predecessor. We can still do PRE of the load, which would insert
900 // a computation of the pointer in this predecessor.
901 if (PredPtrVal == 0) {
902 // Add the entry to the Result list.
903 NonLocalDepResult Entry(Pred,
904 MemDepResult::getClobber(Pred->getTerminator()),
906 Result.push_back(Entry);
908 // Since we had a phi translation failure, the cache for CacheKey won't
909 // include all of the entries that we need to immediately satisfy future
910 // queries. Mark this in NonLocalPointerDeps by setting the
911 // BBSkipFirstBlockPair pointer to null. This requires reuse of the
912 // cached value to do more work but not miss the phi trans failure.
913 NonLocalPointerInfo &NLPI = NonLocalPointerDeps[CacheKey];
914 NLPI.Pair = BBSkipFirstBlockPair();
919 // FIXME: it is entirely possible that PHI translating will end up with
920 // the same value. Consider PHI translating something like:
921 // X = phi [x, bb1], [y, bb2]. PHI translating for bb1 doesn't *need*
922 // to recurse here, pedantically speaking.
924 // If we have a problem phi translating, fall through to the code below
925 // to handle the failure condition.
926 if (getNonLocalPointerDepFromBB(PredPointer,
927 Loc.getWithNewPtr(PredPointer.getAddr()),
930 goto PredTranslationFailure;
933 // Refresh the CacheInfo/Cache pointer so that it isn't invalidated.
934 CacheInfo = &NonLocalPointerDeps[CacheKey];
935 Cache = &CacheInfo->NonLocalDeps;
936 NumSortedEntries = Cache->size();
938 // Since we did phi translation, the "Cache" set won't contain all of the
939 // results for the query. This is ok (we can still use it to accelerate
940 // specific block queries) but we can't do the fastpath "return all
941 // results from the set" Clear out the indicator for this.
942 CacheInfo->Pair = BBSkipFirstBlockPair();
943 CacheInfo->TBAATag = 0;
944 SkipFirstBlock = false;
947 PredTranslationFailure:
950 // Refresh the CacheInfo/Cache pointer if it got invalidated.
951 CacheInfo = &NonLocalPointerDeps[CacheKey];
952 Cache = &CacheInfo->NonLocalDeps;
953 NumSortedEntries = Cache->size();
956 // Since we failed phi translation, the "Cache" set won't contain all of the
957 // results for the query. This is ok (we can still use it to accelerate
958 // specific block queries) but we can't do the fastpath "return all
959 // results from the set". Clear out the indicator for this.
960 CacheInfo->Pair = BBSkipFirstBlockPair();
961 CacheInfo->TBAATag = 0;
963 // If *nothing* works, mark the pointer as being clobbered by the first
964 // instruction in this block.
966 // If this is the magic first block, return this as a clobber of the whole
967 // incoming value. Since we can't phi translate to one of the predecessors,
968 // we have to bail out.
972 for (NonLocalDepInfo::reverse_iterator I = Cache->rbegin(); ; ++I) {
973 assert(I != Cache->rend() && "Didn't find current block??");
974 if (I->getBB() != BB)
977 assert(I->getResult().isNonLocal() &&
978 "Should only be here with transparent block");
979 I->setResult(MemDepResult::getClobber(BB->begin()));
980 ReverseNonLocalPtrDeps[BB->begin()].insert(CacheKey);
981 Result.push_back(NonLocalDepResult(I->getBB(), I->getResult(),
987 // Okay, we're done now. If we added new values to the cache, re-sort it.
988 SortNonLocalDepInfoCache(*Cache, NumSortedEntries);
989 DEBUG(AssertSorted(*Cache));
993 /// RemoveCachedNonLocalPointerDependencies - If P exists in
994 /// CachedNonLocalPointerInfo, remove it.
995 void MemoryDependenceAnalysis::
996 RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair P) {
997 CachedNonLocalPointerInfo::iterator It =
998 NonLocalPointerDeps.find(P);
999 if (It == NonLocalPointerDeps.end()) return;
1001 // Remove all of the entries in the BB->val map. This involves removing
1002 // instructions from the reverse map.
1003 NonLocalDepInfo &PInfo = It->second.NonLocalDeps;
1005 for (unsigned i = 0, e = PInfo.size(); i != e; ++i) {
1006 Instruction *Target = PInfo[i].getResult().getInst();
1007 if (Target == 0) continue; // Ignore non-local dep results.
1008 assert(Target->getParent() == PInfo[i].getBB());
1010 // Eliminating the dirty entry from 'Cache', so update the reverse info.
1011 RemoveFromReverseMap(ReverseNonLocalPtrDeps, Target, P);
1014 // Remove P from NonLocalPointerDeps (which deletes NonLocalDepInfo).
1015 NonLocalPointerDeps.erase(It);
1019 /// invalidateCachedPointerInfo - This method is used to invalidate cached
1020 /// information about the specified pointer, because it may be too
1021 /// conservative in memdep. This is an optional call that can be used when
1022 /// the client detects an equivalence between the pointer and some other
1023 /// value and replaces the other value with ptr. This can make Ptr available
1024 /// in more places that cached info does not necessarily keep.
1025 void MemoryDependenceAnalysis::invalidateCachedPointerInfo(Value *Ptr) {
1026 // If Ptr isn't really a pointer, just ignore it.
1027 if (!Ptr->getType()->isPointerTy()) return;
1028 // Flush store info for the pointer.
1029 RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(Ptr, false));
1030 // Flush load info for the pointer.
1031 RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(Ptr, true));
1034 /// invalidateCachedPredecessors - Clear the PredIteratorCache info.
1035 /// This needs to be done when the CFG changes, e.g., due to splitting
1037 void MemoryDependenceAnalysis::invalidateCachedPredecessors() {
1041 /// removeInstruction - Remove an instruction from the dependence analysis,
1042 /// updating the dependence of instructions that previously depended on it.
1043 /// This method attempts to keep the cache coherent using the reverse map.
1044 void MemoryDependenceAnalysis::removeInstruction(Instruction *RemInst) {
1045 // Walk through the Non-local dependencies, removing this one as the value
1046 // for any cached queries.
1047 NonLocalDepMapType::iterator NLDI = NonLocalDeps.find(RemInst);
1048 if (NLDI != NonLocalDeps.end()) {
1049 NonLocalDepInfo &BlockMap = NLDI->second.first;
1050 for (NonLocalDepInfo::iterator DI = BlockMap.begin(), DE = BlockMap.end();
1052 if (Instruction *Inst = DI->getResult().getInst())
1053 RemoveFromReverseMap(ReverseNonLocalDeps, Inst, RemInst);
1054 NonLocalDeps.erase(NLDI);
1057 // If we have a cached local dependence query for this instruction, remove it.
1059 LocalDepMapType::iterator LocalDepEntry = LocalDeps.find(RemInst);
1060 if (LocalDepEntry != LocalDeps.end()) {
1061 // Remove us from DepInst's reverse set now that the local dep info is gone.
1062 if (Instruction *Inst = LocalDepEntry->second.getInst())
1063 RemoveFromReverseMap(ReverseLocalDeps, Inst, RemInst);
1065 // Remove this local dependency info.
1066 LocalDeps.erase(LocalDepEntry);
1069 // If we have any cached pointer dependencies on this instruction, remove
1070 // them. If the instruction has non-pointer type, then it can't be a pointer
1073 // Remove it from both the load info and the store info. The instruction
1074 // can't be in either of these maps if it is non-pointer.
1075 if (RemInst->getType()->isPointerTy()) {
1076 RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(RemInst, false));
1077 RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(RemInst, true));
1080 // Loop over all of the things that depend on the instruction we're removing.
1082 SmallVector<std::pair<Instruction*, Instruction*>, 8> ReverseDepsToAdd;
1084 // If we find RemInst as a clobber or Def in any of the maps for other values,
1085 // we need to replace its entry with a dirty version of the instruction after
1086 // it. If RemInst is a terminator, we use a null dirty value.
1088 // Using a dirty version of the instruction after RemInst saves having to scan
1089 // the entire block to get to this point.
1090 MemDepResult NewDirtyVal;
1091 if (!RemInst->isTerminator())
1092 NewDirtyVal = MemDepResult::getDirty(++BasicBlock::iterator(RemInst));
1094 ReverseDepMapType::iterator ReverseDepIt = ReverseLocalDeps.find(RemInst);
1095 if (ReverseDepIt != ReverseLocalDeps.end()) {
1096 SmallPtrSet<Instruction*, 4> &ReverseDeps = ReverseDepIt->second;
1097 // RemInst can't be the terminator if it has local stuff depending on it.
1098 assert(!ReverseDeps.empty() && !isa<TerminatorInst>(RemInst) &&
1099 "Nothing can locally depend on a terminator");
1101 for (SmallPtrSet<Instruction*, 4>::iterator I = ReverseDeps.begin(),
1102 E = ReverseDeps.end(); I != E; ++I) {
1103 Instruction *InstDependingOnRemInst = *I;
1104 assert(InstDependingOnRemInst != RemInst &&
1105 "Already removed our local dep info");
1107 LocalDeps[InstDependingOnRemInst] = NewDirtyVal;
1109 // Make sure to remember that new things depend on NewDepInst.
1110 assert(NewDirtyVal.getInst() && "There is no way something else can have "
1111 "a local dep on this if it is a terminator!");
1112 ReverseDepsToAdd.push_back(std::make_pair(NewDirtyVal.getInst(),
1113 InstDependingOnRemInst));
1116 ReverseLocalDeps.erase(ReverseDepIt);
1118 // Add new reverse deps after scanning the set, to avoid invalidating the
1119 // 'ReverseDeps' reference.
1120 while (!ReverseDepsToAdd.empty()) {
1121 ReverseLocalDeps[ReverseDepsToAdd.back().first]
1122 .insert(ReverseDepsToAdd.back().second);
1123 ReverseDepsToAdd.pop_back();
1127 ReverseDepIt = ReverseNonLocalDeps.find(RemInst);
1128 if (ReverseDepIt != ReverseNonLocalDeps.end()) {
1129 SmallPtrSet<Instruction*, 4> &Set = ReverseDepIt->second;
1130 for (SmallPtrSet<Instruction*, 4>::iterator I = Set.begin(), E = Set.end();
1132 assert(*I != RemInst && "Already removed NonLocalDep info for RemInst");
1134 PerInstNLInfo &INLD = NonLocalDeps[*I];
1135 // The information is now dirty!
1138 for (NonLocalDepInfo::iterator DI = INLD.first.begin(),
1139 DE = INLD.first.end(); DI != DE; ++DI) {
1140 if (DI->getResult().getInst() != RemInst) continue;
1142 // Convert to a dirty entry for the subsequent instruction.
1143 DI->setResult(NewDirtyVal);
1145 if (Instruction *NextI = NewDirtyVal.getInst())
1146 ReverseDepsToAdd.push_back(std::make_pair(NextI, *I));
1150 ReverseNonLocalDeps.erase(ReverseDepIt);
1152 // Add new reverse deps after scanning the set, to avoid invalidating 'Set'
1153 while (!ReverseDepsToAdd.empty()) {
1154 ReverseNonLocalDeps[ReverseDepsToAdd.back().first]
1155 .insert(ReverseDepsToAdd.back().second);
1156 ReverseDepsToAdd.pop_back();
1160 // If the instruction is in ReverseNonLocalPtrDeps then it appears as a
1161 // value in the NonLocalPointerDeps info.
1162 ReverseNonLocalPtrDepTy::iterator ReversePtrDepIt =
1163 ReverseNonLocalPtrDeps.find(RemInst);
1164 if (ReversePtrDepIt != ReverseNonLocalPtrDeps.end()) {
1165 SmallPtrSet<ValueIsLoadPair, 4> &Set = ReversePtrDepIt->second;
1166 SmallVector<std::pair<Instruction*, ValueIsLoadPair>,8> ReversePtrDepsToAdd;
1168 for (SmallPtrSet<ValueIsLoadPair, 4>::iterator I = Set.begin(),
1169 E = Set.end(); I != E; ++I) {
1170 ValueIsLoadPair P = *I;
1171 assert(P.getPointer() != RemInst &&
1172 "Already removed NonLocalPointerDeps info for RemInst");
1174 NonLocalDepInfo &NLPDI = NonLocalPointerDeps[P].NonLocalDeps;
1176 // The cache is not valid for any specific block anymore.
1177 NonLocalPointerDeps[P].Pair = BBSkipFirstBlockPair();
1178 NonLocalPointerDeps[P].TBAATag = 0;
1180 // Update any entries for RemInst to use the instruction after it.
1181 for (NonLocalDepInfo::iterator DI = NLPDI.begin(), DE = NLPDI.end();
1183 if (DI->getResult().getInst() != RemInst) continue;
1185 // Convert to a dirty entry for the subsequent instruction.
1186 DI->setResult(NewDirtyVal);
1188 if (Instruction *NewDirtyInst = NewDirtyVal.getInst())
1189 ReversePtrDepsToAdd.push_back(std::make_pair(NewDirtyInst, P));
1192 // Re-sort the NonLocalDepInfo. Changing the dirty entry to its
1193 // subsequent value may invalidate the sortedness.
1194 std::sort(NLPDI.begin(), NLPDI.end());
1197 ReverseNonLocalPtrDeps.erase(ReversePtrDepIt);
1199 while (!ReversePtrDepsToAdd.empty()) {
1200 ReverseNonLocalPtrDeps[ReversePtrDepsToAdd.back().first]
1201 .insert(ReversePtrDepsToAdd.back().second);
1202 ReversePtrDepsToAdd.pop_back();
1207 assert(!NonLocalDeps.count(RemInst) && "RemInst got reinserted?");
1208 AA->deleteValue(RemInst);
1209 DEBUG(verifyRemoved(RemInst));
1211 /// verifyRemoved - Verify that the specified instruction does not occur
1212 /// in our internal data structures.
1213 void MemoryDependenceAnalysis::verifyRemoved(Instruction *D) const {
1214 for (LocalDepMapType::const_iterator I = LocalDeps.begin(),
1215 E = LocalDeps.end(); I != E; ++I) {
1216 assert(I->first != D && "Inst occurs in data structures");
1217 assert(I->second.getInst() != D &&
1218 "Inst occurs in data structures");
1221 for (CachedNonLocalPointerInfo::const_iterator I =NonLocalPointerDeps.begin(),
1222 E = NonLocalPointerDeps.end(); I != E; ++I) {
1223 assert(I->first.getPointer() != D && "Inst occurs in NLPD map key");
1224 const NonLocalDepInfo &Val = I->second.NonLocalDeps;
1225 for (NonLocalDepInfo::const_iterator II = Val.begin(), E = Val.end();
1227 assert(II->getResult().getInst() != D && "Inst occurs as NLPD value");
1230 for (NonLocalDepMapType::const_iterator I = NonLocalDeps.begin(),
1231 E = NonLocalDeps.end(); I != E; ++I) {
1232 assert(I->first != D && "Inst occurs in data structures");
1233 const PerInstNLInfo &INLD = I->second;
1234 for (NonLocalDepInfo::const_iterator II = INLD.first.begin(),
1235 EE = INLD.first.end(); II != EE; ++II)
1236 assert(II->getResult().getInst() != D && "Inst occurs in data structures");
1239 for (ReverseDepMapType::const_iterator I = ReverseLocalDeps.begin(),
1240 E = ReverseLocalDeps.end(); I != E; ++I) {
1241 assert(I->first != D && "Inst occurs in data structures");
1242 for (SmallPtrSet<Instruction*, 4>::const_iterator II = I->second.begin(),
1243 EE = I->second.end(); II != EE; ++II)
1244 assert(*II != D && "Inst occurs in data structures");
1247 for (ReverseDepMapType::const_iterator I = ReverseNonLocalDeps.begin(),
1248 E = ReverseNonLocalDeps.end();
1250 assert(I->first != D && "Inst occurs in data structures");
1251 for (SmallPtrSet<Instruction*, 4>::const_iterator II = I->second.begin(),
1252 EE = I->second.end(); II != EE; ++II)
1253 assert(*II != D && "Inst occurs in data structures");
1256 for (ReverseNonLocalPtrDepTy::const_iterator
1257 I = ReverseNonLocalPtrDeps.begin(),
1258 E = ReverseNonLocalPtrDeps.end(); I != E; ++I) {
1259 assert(I->first != D && "Inst occurs in rev NLPD map");
1261 for (SmallPtrSet<ValueIsLoadPair, 4>::const_iterator II = I->second.begin(),
1262 E = I->second.end(); II != E; ++II)
1263 assert(*II != ValueIsLoadPair(D, false) &&
1264 *II != ValueIsLoadPair(D, true) &&
1265 "Inst occurs in ReverseNonLocalPtrDeps map");