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Diffstat (limited to 'llvm/lib/Analysis/MemoryDependenceAnalysis.cpp')
-rw-r--r--llvm/lib/Analysis/MemoryDependenceAnalysis.cpp166
1 files changed, 95 insertions, 71 deletions
diff --git a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
index 8390ee9..8ae5e4c 100644
--- a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
+++ b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
@@ -19,6 +19,7 @@
#include "llvm/Instructions.h"
#include "llvm/IntrinsicInst.h"
#include "llvm/Function.h"
+#include "llvm/LLVMContext.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/InstructionSimplify.h"
@@ -108,18 +109,19 @@ getCallSiteDependencyFrom(CallSite CS, bool isReadOnlyCall,
Instruction *Inst = --ScanIt;
// If this inst is a memory op, get the pointer it accessed
- Value *Pointer = 0;
- uint64_t PointerSize = 0;
+ AliasAnalysis::Location Loc;
if (StoreInst *S = dyn_cast<StoreInst>(Inst)) {
- Pointer = S->getPointerOperand();
- PointerSize = AA->getTypeStoreSize(S->getOperand(0)->getType());
+ Loc = AliasAnalysis::Location(S->getPointerOperand(),
+ AA->getTypeStoreSize(S->getValueOperand()
+ ->getType()),
+ S->getMetadata(LLVMContext::MD_tbaa));
} else if (VAArgInst *V = dyn_cast<VAArgInst>(Inst)) {
- Pointer = V->getOperand(0);
- PointerSize = AA->getTypeStoreSize(V->getType());
+ Loc = AliasAnalysis::Location(V->getPointerOperand(),
+ AA->getTypeStoreSize(V->getType()),
+ V->getMetadata(LLVMContext::MD_tbaa));
} else if (const CallInst *CI = isFreeCall(Inst)) {
- Pointer = CI->getArgOperand(0);
// calls to free() erase the entire structure
- PointerSize = ~0ULL;
+ Loc = AliasAnalysis::Location(CI->getArgOperand(0));
} else if (CallSite InstCS = cast<Value>(Inst)) {
// Debug intrinsics don't cause dependences.
if (isa<DbgInfoIntrinsic>(Inst)) continue;
@@ -143,7 +145,7 @@ getCallSiteDependencyFrom(CallSite CS, bool isReadOnlyCall,
continue;
}
- if (AA->getModRefInfo(CS, Pointer, PointerSize) != AliasAnalysis::NoModRef)
+ if (AA->getModRefInfo(CS, Loc) != AliasAnalysis::NoModRef)
return MemDepResult::getClobber(Inst);
}
@@ -158,7 +160,7 @@ getCallSiteDependencyFrom(CallSite CS, bool isReadOnlyCall,
/// location depends. If isLoad is true, this routine ignore may-aliases with
/// read-only operations.
MemDepResult MemoryDependenceAnalysis::
-getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad,
+getPointerDependencyFrom(const AliasAnalysis::Location &MemLoc, bool isLoad,
BasicBlock::iterator ScanIt, BasicBlock *BB) {
Value *InvariantTag = 0;
@@ -184,7 +186,8 @@ getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad,
// FIXME: This only considers queries directly on the invariant-tagged
// pointer, not on query pointers that are indexed off of them. It'd
// be nice to handle that at some point.
- AliasAnalysis::AliasResult R = AA->alias(II->getArgOperand(2), MemPtr);
+ AliasAnalysis::AliasResult R =
+ AA->alias(AliasAnalysis::Location(II->getArgOperand(2)), MemLoc);
if (R == AliasAnalysis::MustAlias)
InvariantTag = II->getArgOperand(0);
@@ -197,7 +200,8 @@ getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad,
// FIXME: This only considers queries directly on the invariant-tagged
// pointer, not on query pointers that are indexed off of them. It'd
// be nice to handle that at some point.
- AliasAnalysis::AliasResult R = AA->alias(II->getArgOperand(1), MemPtr);
+ AliasAnalysis::AliasResult R =
+ AA->alias(AliasAnalysis::Location(II->getArgOperand(1)), MemLoc);
if (R == AliasAnalysis::MustAlias)
return MemDepResult::getDef(II);
continue;
@@ -216,10 +220,12 @@ getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad,
if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) {
Value *Pointer = LI->getPointerOperand();
uint64_t PointerSize = AA->getTypeStoreSize(LI->getType());
+ MDNode *TBAATag = LI->getMetadata(LLVMContext::MD_tbaa);
// If we found a pointer, check if it could be the same as our pointer.
AliasAnalysis::AliasResult R =
- AA->alias(Pointer, PointerSize, MemPtr, MemSize);
+ AA->alias(AliasAnalysis::Location(Pointer, PointerSize, TBAATag),
+ MemLoc);
if (R == AliasAnalysis::NoAlias)
continue;
@@ -239,17 +245,19 @@ getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad,
// If alias analysis can tell that this store is guaranteed to not modify
// the query pointer, ignore it. Use getModRefInfo to handle cases where
// the query pointer points to constant memory etc.
- if (AA->getModRefInfo(SI, MemPtr, MemSize) == AliasAnalysis::NoModRef)
+ if (AA->getModRefInfo(SI, MemLoc) == AliasAnalysis::NoModRef)
continue;
// Ok, this store might clobber the query pointer. Check to see if it is
// a must alias: in this case, we want to return this as a def.
Value *Pointer = SI->getPointerOperand();
uint64_t PointerSize = AA->getTypeStoreSize(SI->getOperand(0)->getType());
+ MDNode *TBAATag = SI->getMetadata(LLVMContext::MD_tbaa);
// If we found a pointer, check if it could be the same as our pointer.
AliasAnalysis::AliasResult R =
- AA->alias(Pointer, PointerSize, MemPtr, MemSize);
+ AA->alias(AliasAnalysis::Location(Pointer, PointerSize, TBAATag),
+ MemLoc);
if (R == AliasAnalysis::NoAlias)
continue;
@@ -268,7 +276,7 @@ getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad,
// need to continue scanning until the malloc call.
if (isa<AllocaInst>(Inst) ||
(isa<CallInst>(Inst) && extractMallocCall(Inst))) {
- Value *AccessPtr = MemPtr->getUnderlyingObject();
+ const Value *AccessPtr = MemLoc.Ptr->getUnderlyingObject();
if (AccessPtr == Inst ||
AA->alias(Inst, 1, AccessPtr, 1) == AliasAnalysis::MustAlias)
@@ -277,7 +285,7 @@ getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad,
}
// See if this instruction (e.g. a call or vaarg) mod/ref's the pointer.
- switch (AA->getModRefInfo(Inst, MemPtr, MemSize)) {
+ switch (AA->getModRefInfo(Inst, MemLoc)) {
case AliasAnalysis::NoModRef:
// If the call has no effect on the queried pointer, just ignore it.
continue;
@@ -327,8 +335,7 @@ MemDepResult MemoryDependenceAnalysis::getDependency(Instruction *QueryInst) {
BasicBlock *QueryParent = QueryInst->getParent();
- Value *MemPtr = 0;
- uint64_t MemSize = 0;
+ AliasAnalysis::Location MemLoc;
// Do the scan.
if (BasicBlock::iterator(QueryInst) == QueryParent->begin()) {
@@ -343,23 +350,23 @@ MemDepResult MemoryDependenceAnalysis::getDependency(Instruction *QueryInst) {
// previous instruction as a clobber.
if (SI->isVolatile())
LocalCache = MemDepResult::getClobber(--BasicBlock::iterator(ScanPos));
- else {
- MemPtr = SI->getPointerOperand();
- MemSize = AA->getTypeStoreSize(SI->getOperand(0)->getType());
- }
+ else
+ MemLoc = AliasAnalysis::Location(SI->getPointerOperand(),
+ AA->getTypeStoreSize(SI->getOperand(0)
+ ->getType()),
+ SI->getMetadata(LLVMContext::MD_tbaa));
} else if (LoadInst *LI = dyn_cast<LoadInst>(QueryInst)) {
// If this is a volatile load, don't mess around with it. Just return the
// previous instruction as a clobber.
if (LI->isVolatile())
LocalCache = MemDepResult::getClobber(--BasicBlock::iterator(ScanPos));
- else {
- MemPtr = LI->getPointerOperand();
- MemSize = AA->getTypeStoreSize(LI->getType());
- }
+ else
+ MemLoc = AliasAnalysis::Location(LI->getPointerOperand(),
+ AA->getTypeStoreSize(LI->getType()),
+ LI->getMetadata(LLVMContext::MD_tbaa));
} else if (const CallInst *CI = isFreeCall(QueryInst)) {
- MemPtr = CI->getArgOperand(0);
// calls to free() erase the entire structure, not just a field.
- MemSize = ~0UL;
+ MemLoc = AliasAnalysis::Location(CI->getArgOperand(0));
} else if (isa<CallInst>(QueryInst) || isa<InvokeInst>(QueryInst)) {
int IntrinsicID = 0; // Intrinsic IDs start at 1.
IntrinsicInst *II = dyn_cast<IntrinsicInst>(QueryInst);
@@ -370,12 +377,16 @@ MemDepResult MemoryDependenceAnalysis::getDependency(Instruction *QueryInst) {
case Intrinsic::lifetime_start:
case Intrinsic::lifetime_end:
case Intrinsic::invariant_start:
- MemPtr = II->getArgOperand(1);
- MemSize = cast<ConstantInt>(II->getArgOperand(0))->getZExtValue();
+ MemLoc = AliasAnalysis::Location(II->getArgOperand(1),
+ cast<ConstantInt>(II->getArgOperand(0))
+ ->getZExtValue(),
+ II->getMetadata(LLVMContext::MD_tbaa));
break;
case Intrinsic::invariant_end:
- MemPtr = II->getArgOperand(2);
- MemSize = cast<ConstantInt>(II->getArgOperand(1))->getZExtValue();
+ MemLoc = AliasAnalysis::Location(II->getArgOperand(2),
+ cast<ConstantInt>(II->getArgOperand(1))
+ ->getZExtValue(),
+ II->getMetadata(LLVMContext::MD_tbaa));
break;
default:
CallSite QueryCS(QueryInst);
@@ -390,12 +401,12 @@ MemDepResult MemoryDependenceAnalysis::getDependency(Instruction *QueryInst) {
}
// If we need to do a pointer scan, make it happen.
- if (MemPtr) {
+ if (MemLoc.Ptr) {
bool isLoad = !QueryInst->mayWriteToMemory();
if (IntrinsicInst *II = dyn_cast<MemoryUseIntrinsic>(QueryInst)) {
isLoad |= II->getIntrinsicID() == Intrinsic::lifetime_end;
}
- LocalCache = getPointerDependencyFrom(MemPtr, MemSize, isLoad, ScanPos,
+ LocalCache = getPointerDependencyFrom(MemLoc, isLoad, ScanPos,
QueryParent);
}
@@ -570,31 +581,27 @@ MemoryDependenceAnalysis::getNonLocalCallDependency(CallSite QueryCS) {
/// own block.
///
void MemoryDependenceAnalysis::
-getNonLocalPointerDependency(Value *Pointer, bool isLoad, BasicBlock *FromBB,
+getNonLocalPointerDependency(const AliasAnalysis::Location &Loc, bool isLoad,
+ BasicBlock *FromBB,
SmallVectorImpl<NonLocalDepResult> &Result) {
- assert(Pointer->getType()->isPointerTy() &&
+ assert(Loc.Ptr->getType()->isPointerTy() &&
"Can't get pointer deps of a non-pointer!");
Result.clear();
- // We know that the pointer value is live into FromBB find the def/clobbers
- // from presecessors.
- const Type *EltTy = cast<PointerType>(Pointer->getType())->getElementType();
- uint64_t PointeeSize = AA->getTypeStoreSize(EltTy);
-
- PHITransAddr Address(Pointer, TD);
+ PHITransAddr Address(const_cast<Value *>(Loc.Ptr), TD);
// This is the set of blocks we've inspected, and the pointer we consider in
// each block. Because of critical edges, we currently bail out if querying
// a block with multiple different pointers. This can happen during PHI
// translation.
DenseMap<BasicBlock*, Value*> Visited;
- if (!getNonLocalPointerDepFromBB(Address, PointeeSize, isLoad, FromBB,
+ if (!getNonLocalPointerDepFromBB(Address, Loc, isLoad, FromBB,
Result, Visited, true))
return;
Result.clear();
Result.push_back(NonLocalDepResult(FromBB,
MemDepResult::getClobber(FromBB->begin()),
- Pointer));
+ const_cast<Value *>(Loc.Ptr)));
}
/// GetNonLocalInfoForBlock - Compute the memdep value for BB with
@@ -602,7 +609,7 @@ getNonLocalPointerDependency(Value *Pointer, bool isLoad, BasicBlock *FromBB,
/// lookup (which may use dirty cache info if available). If we do a lookup,
/// add the result to the cache.
MemDepResult MemoryDependenceAnalysis::
-GetNonLocalInfoForBlock(Value *Pointer, uint64_t PointeeSize,
+GetNonLocalInfoForBlock(const AliasAnalysis::Location &Loc,
bool isLoad, BasicBlock *BB,
NonLocalDepInfo *Cache, unsigned NumSortedEntries) {
@@ -636,15 +643,14 @@ GetNonLocalInfoForBlock(Value *Pointer, uint64_t PointeeSize,
ScanPos = ExistingResult->getResult().getInst();
// Eliminating the dirty entry from 'Cache', so update the reverse info.
- ValueIsLoadPair CacheKey(Pointer, isLoad);
+ ValueIsLoadPair CacheKey(Loc.Ptr, isLoad);
RemoveFromReverseMap(ReverseNonLocalPtrDeps, ScanPos, CacheKey);
} else {
++NumUncacheNonLocalPtr;
}
// Scan the block for the dependency.
- MemDepResult Dep = getPointerDependencyFrom(Pointer, PointeeSize, isLoad,
- ScanPos, BB);
+ MemDepResult Dep = getPointerDependencyFrom(Loc, isLoad, ScanPos, BB);
// If we had a dirty entry for the block, update it. Otherwise, just add
// a new entry.
@@ -663,7 +669,7 @@ GetNonLocalInfoForBlock(Value *Pointer, uint64_t PointeeSize,
// update MemDep when we remove instructions.
Instruction *Inst = Dep.getInst();
assert(Inst && "Didn't depend on anything?");
- ValueIsLoadPair CacheKey(Pointer, isLoad);
+ ValueIsLoadPair CacheKey(Loc.Ptr, isLoad);
ReverseNonLocalPtrDeps[Inst].insert(CacheKey);
return Dep;
}
@@ -717,7 +723,8 @@ SortNonLocalDepInfoCache(MemoryDependenceAnalysis::NonLocalDepInfo &Cache,
/// not compute dependence information for some reason. This should be treated
/// as a clobber dependence on the first instruction in the predecessor block.
bool MemoryDependenceAnalysis::
-getNonLocalPointerDepFromBB(const PHITransAddr &Pointer, uint64_t PointeeSize,
+getNonLocalPointerDepFromBB(const PHITransAddr &Pointer,
+ const AliasAnalysis::Location &Loc,
bool isLoad, BasicBlock *StartBB,
SmallVectorImpl<NonLocalDepResult> &Result,
DenseMap<BasicBlock*, Value*> &Visited,
@@ -725,14 +732,23 @@ getNonLocalPointerDepFromBB(const PHITransAddr &Pointer, uint64_t PointeeSize,
// Look up the cached info for Pointer.
ValueIsLoadPair CacheKey(Pointer.getAddr(), isLoad);
-
- std::pair<BBSkipFirstBlockPair, NonLocalDepInfo> *CacheInfo =
- &NonLocalPointerDeps[CacheKey];
- NonLocalDepInfo *Cache = &CacheInfo->second;
+ NonLocalPointerInfo *CacheInfo = &NonLocalPointerDeps[CacheKey];
+
+ // If this query's TBAATag is inconsistent with the cached one, discard the
+ // tag and restart the query.
+ if (CacheInfo->TBAATag != Loc.TBAATag) {
+ CacheInfo->TBAATag = 0;
+ NonLocalPointerDeps.erase(CacheKey);
+ return getNonLocalPointerDepFromBB(Pointer, Loc.getWithoutTBAATag(),
+ isLoad, StartBB, Result, Visited,
+ SkipFirstBlock);
+ }
+
+ NonLocalDepInfo *Cache = &CacheInfo->NonLocalDeps;
// If we have valid cached information for exactly the block we are
// investigating, just return it with no recomputation.
- if (CacheInfo->first == BBSkipFirstBlockPair(StartBB, SkipFirstBlock)) {
+ if (CacheInfo->Pair == BBSkipFirstBlockPair(StartBB, SkipFirstBlock)) {
// We have a fully cached result for this query then we can just return the
// cached results and populate the visited set. However, we have to verify
// that we don't already have conflicting results for these blocks. Check
@@ -768,9 +784,11 @@ getNonLocalPointerDepFromBB(const PHITransAddr &Pointer, uint64_t PointeeSize,
// than its valid cache info. If empty, the result will be valid cache info,
// otherwise it isn't.
if (Cache->empty())
- CacheInfo->first = BBSkipFirstBlockPair(StartBB, SkipFirstBlock);
- else
- CacheInfo->first = BBSkipFirstBlockPair();
+ CacheInfo->Pair = BBSkipFirstBlockPair(StartBB, SkipFirstBlock);
+ else {
+ CacheInfo->Pair = BBSkipFirstBlockPair();
+ CacheInfo->TBAATag = 0;
+ }
SmallVector<BasicBlock*, 32> Worklist;
Worklist.push_back(StartBB);
@@ -795,8 +813,7 @@ getNonLocalPointerDepFromBB(const PHITransAddr &Pointer, uint64_t PointeeSize,
// Get the dependency info for Pointer in BB. If we have cached
// information, we will use it, otherwise we compute it.
DEBUG(AssertSorted(*Cache, NumSortedEntries));
- MemDepResult Dep = GetNonLocalInfoForBlock(Pointer.getAddr(), PointeeSize,
- isLoad, BB, Cache,
+ MemDepResult Dep = GetNonLocalInfoForBlock(Loc, isLoad, BB, Cache,
NumSortedEntries);
// If we got a Def or Clobber, add this to the list of results.
@@ -893,7 +910,9 @@ getNonLocalPointerDepFromBB(const PHITransAddr &Pointer, uint64_t PointeeSize,
// queries. Mark this in NonLocalPointerDeps by setting the
// BBSkipFirstBlockPair pointer to null. This requires reuse of the
// cached value to do more work but not miss the phi trans failure.
- NonLocalPointerDeps[CacheKey].first = BBSkipFirstBlockPair();
+ NonLocalPointerInfo &NLPI = NonLocalPointerDeps[CacheKey];
+ NLPI.Pair = BBSkipFirstBlockPair();
+ NLPI.TBAATag = 0;
continue;
}
@@ -904,21 +923,24 @@ getNonLocalPointerDepFromBB(const PHITransAddr &Pointer, uint64_t PointeeSize,
// If we have a problem phi translating, fall through to the code below
// to handle the failure condition.
- if (getNonLocalPointerDepFromBB(PredPointer, PointeeSize, isLoad, Pred,
+ if (getNonLocalPointerDepFromBB(PredPointer,
+ Loc.getWithNewPtr(PredPointer.getAddr()),
+ isLoad, Pred,
Result, Visited))
goto PredTranslationFailure;
}
// Refresh the CacheInfo/Cache pointer so that it isn't invalidated.
CacheInfo = &NonLocalPointerDeps[CacheKey];
- Cache = &CacheInfo->second;
+ Cache = &CacheInfo->NonLocalDeps;
NumSortedEntries = Cache->size();
// Since we did phi translation, the "Cache" set won't contain all of the
// results for the query. This is ok (we can still use it to accelerate
// specific block queries) but we can't do the fastpath "return all
// results from the set" Clear out the indicator for this.
- CacheInfo->first = BBSkipFirstBlockPair();
+ CacheInfo->Pair = BBSkipFirstBlockPair();
+ CacheInfo->TBAATag = 0;
SkipFirstBlock = false;
continue;
@@ -927,7 +949,7 @@ getNonLocalPointerDepFromBB(const PHITransAddr &Pointer, uint64_t PointeeSize,
if (Cache == 0) {
// Refresh the CacheInfo/Cache pointer if it got invalidated.
CacheInfo = &NonLocalPointerDeps[CacheKey];
- Cache = &CacheInfo->second;
+ Cache = &CacheInfo->NonLocalDeps;
NumSortedEntries = Cache->size();
}
@@ -935,7 +957,8 @@ getNonLocalPointerDepFromBB(const PHITransAddr &Pointer, uint64_t PointeeSize,
// results for the query. This is ok (we can still use it to accelerate
// specific block queries) but we can't do the fastpath "return all
// results from the set". Clear out the indicator for this.
- CacheInfo->first = BBSkipFirstBlockPair();
+ CacheInfo->Pair = BBSkipFirstBlockPair();
+ CacheInfo->TBAATag = 0;
// If *nothing* works, mark the pointer as being clobbered by the first
// instruction in this block.
@@ -977,7 +1000,7 @@ RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair P) {
// Remove all of the entries in the BB->val map. This involves removing
// instructions from the reverse map.
- NonLocalDepInfo &PInfo = It->second.second;
+ NonLocalDepInfo &PInfo = It->second.NonLocalDeps;
for (unsigned i = 0, e = PInfo.size(); i != e; ++i) {
Instruction *Target = PInfo[i].getResult().getInst();
@@ -1148,10 +1171,11 @@ void MemoryDependenceAnalysis::removeInstruction(Instruction *RemInst) {
assert(P.getPointer() != RemInst &&
"Already removed NonLocalPointerDeps info for RemInst");
- NonLocalDepInfo &NLPDI = NonLocalPointerDeps[P].second;
+ NonLocalDepInfo &NLPDI = NonLocalPointerDeps[P].NonLocalDeps;
// The cache is not valid for any specific block anymore.
- NonLocalPointerDeps[P].first = BBSkipFirstBlockPair();
+ NonLocalPointerDeps[P].Pair = BBSkipFirstBlockPair();
+ NonLocalPointerDeps[P].TBAATag = 0;
// Update any entries for RemInst to use the instruction after it.
for (NonLocalDepInfo::iterator DI = NLPDI.begin(), DE = NLPDI.end();
@@ -1197,7 +1221,7 @@ void MemoryDependenceAnalysis::verifyRemoved(Instruction *D) const {
for (CachedNonLocalPointerInfo::const_iterator I =NonLocalPointerDeps.begin(),
E = NonLocalPointerDeps.end(); I != E; ++I) {
assert(I->first.getPointer() != D && "Inst occurs in NLPD map key");
- const NonLocalDepInfo &Val = I->second.second;
+ const NonLocalDepInfo &Val = I->second.NonLocalDeps;
for (NonLocalDepInfo::const_iterator II = Val.begin(), E = Val.end();
II != E; ++II)
assert(II->getResult().getInst() != D && "Inst occurs as NLPD value");
generated by cgit v1.1 at 2025-11-04 01:12:43 +0000