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-rw-r--r--lib/Analysis/BasicAliasAnalysis.cpp155
1 files changed, 58 insertions, 97 deletions
diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index a61faca2e54e..d11a748e4bf9 100644
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -105,7 +105,7 @@ static uint64_t getObjectSize(const Value *V, const DataLayout &DL,
uint64_t Size;
if (getObjectSize(V, Size, DL, &TLI, RoundToAlign))
return Size;
- return AliasAnalysis::UnknownSize;
+ return MemoryLocation::UnknownSize;
}
/// isObjectSmallerThan - Return true if we can prove that the object specified
@@ -146,7 +146,7 @@ static bool isObjectSmallerThan(const Value *V, uint64_t Size,
// reads a bit past the end given sufficient alignment.
uint64_t ObjectSize = getObjectSize(V, DL, TLI, /*RoundToAlign*/true);
- return ObjectSize != AliasAnalysis::UnknownSize && ObjectSize < Size;
+ return ObjectSize != MemoryLocation::UnknownSize && ObjectSize < Size;
}
/// isObjectSize - Return true if we can prove that the object specified
@@ -154,7 +154,7 @@ static bool isObjectSmallerThan(const Value *V, uint64_t Size,
static bool isObjectSize(const Value *V, uint64_t Size,
const DataLayout &DL, const TargetLibraryInfo &TLI) {
uint64_t ObjectSize = getObjectSize(V, DL, TLI);
- return ObjectSize != AliasAnalysis::UnknownSize && ObjectSize == Size;
+ return ObjectSize != MemoryLocation::UnknownSize && ObjectSize == Size;
}
//===----------------------------------------------------------------------===//
@@ -182,7 +182,7 @@ namespace {
return !operator==(Other);
}
};
-}
+} // namespace
/// GetLinearExpression - Analyze the specified value as a linear expression:
@@ -459,7 +459,8 @@ namespace {
AU.addRequired<TargetLibraryInfoWrapperPass>();
}
- AliasResult alias(const Location &LocA, const Location &LocB) override {
+ AliasResult alias(const MemoryLocation &LocA,
+ const MemoryLocation &LocB) override {
assert(AliasCache.empty() && "AliasCache must be cleared after use!");
assert(notDifferentParent(LocA.Ptr, LocB.Ptr) &&
"BasicAliasAnalysis doesn't support interprocedural queries.");
@@ -475,18 +476,19 @@ namespace {
}
ModRefResult getModRefInfo(ImmutableCallSite CS,
- const Location &Loc) override;
+ const MemoryLocation &Loc) override;
ModRefResult getModRefInfo(ImmutableCallSite CS1,
ImmutableCallSite CS2) override;
/// pointsToConstantMemory - Chase pointers until we find a (constant
/// global) or not.
- bool pointsToConstantMemory(const Location &Loc, bool OrLocal) override;
+ bool pointsToConstantMemory(const MemoryLocation &Loc,
+ bool OrLocal) override;
/// Get the location associated with a pointer argument of a callsite.
- Location getArgLocation(ImmutableCallSite CS, unsigned ArgIdx,
- ModRefResult &Mask) override;
+ ModRefResult getArgModRefInfo(ImmutableCallSite CS,
+ unsigned ArgIdx) override;
/// getModRefBehavior - Return the behavior when calling the given
/// call site.
@@ -508,7 +510,7 @@ namespace {
private:
// AliasCache - Track alias queries to guard against recursion.
- typedef std::pair<Location, Location> LocPair;
+ typedef std::pair<MemoryLocation, MemoryLocation> LocPair;
typedef SmallDenseMap<LocPair, AliasResult, 8> AliasCacheTy;
AliasCacheTy AliasCache;
@@ -592,8 +594,8 @@ ImmutablePass *llvm::createBasicAliasAnalysisPass() {
/// pointsToConstantMemory - Returns whether the given pointer value
/// points to memory that is local to the function, with global constants being
/// considered local to all functions.
-bool
-BasicAliasAnalysis::pointsToConstantMemory(const Location &Loc, bool OrLocal) {
+bool BasicAliasAnalysis::pointsToConstantMemory(const MemoryLocation &Loc,
+ bool OrLocal) {
assert(Visited.empty() && "Visited must be cleared after use!");
unsigned MaxLookup = 8;
@@ -652,6 +654,8 @@ BasicAliasAnalysis::pointsToConstantMemory(const Location &Loc, bool OrLocal) {
return Worklist.empty();
}
+// FIXME: This code is duplicated with MemoryLocation and should be hoisted to
+// some common utility location.
static bool isMemsetPattern16(const Function *MS,
const TargetLibraryInfo &TLI) {
if (TLI.has(LibFunc::memset_pattern16) &&
@@ -715,84 +719,33 @@ BasicAliasAnalysis::getModRefBehavior(const Function *F) {
return ModRefBehavior(AliasAnalysis::getModRefBehavior(F) & Min);
}
-AliasAnalysis::Location
-BasicAliasAnalysis::getArgLocation(ImmutableCallSite CS, unsigned ArgIdx,
- ModRefResult &Mask) {
- Location Loc = AliasAnalysis::getArgLocation(CS, ArgIdx, Mask);
- const TargetLibraryInfo &TLI =
- getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
- const IntrinsicInst *II = dyn_cast<IntrinsicInst>(CS.getInstruction());
- if (II != nullptr)
+AliasAnalysis::ModRefResult
+BasicAliasAnalysis::getArgModRefInfo(ImmutableCallSite CS, unsigned ArgIdx) {
+ if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(CS.getInstruction()))
switch (II->getIntrinsicID()) {
- default: break;
+ default:
+ break;
case Intrinsic::memset:
case Intrinsic::memcpy:
- case Intrinsic::memmove: {
+ case Intrinsic::memmove:
assert((ArgIdx == 0 || ArgIdx == 1) &&
"Invalid argument index for memory intrinsic");
- if (ConstantInt *LenCI = dyn_cast<ConstantInt>(II->getArgOperand(2)))
- Loc.Size = LenCI->getZExtValue();
- assert(Loc.Ptr == II->getArgOperand(ArgIdx) &&
- "Memory intrinsic location pointer not argument?");
- Mask = ArgIdx ? Ref : Mod;
- break;
- }
- case Intrinsic::lifetime_start:
- case Intrinsic::lifetime_end:
- case Intrinsic::invariant_start: {
- assert(ArgIdx == 1 && "Invalid argument index");
- assert(Loc.Ptr == II->getArgOperand(ArgIdx) &&
- "Intrinsic location pointer not argument?");
- Loc.Size = cast<ConstantInt>(II->getArgOperand(0))->getZExtValue();
- break;
- }
- case Intrinsic::invariant_end: {
- assert(ArgIdx == 2 && "Invalid argument index");
- assert(Loc.Ptr == II->getArgOperand(ArgIdx) &&
- "Intrinsic location pointer not argument?");
- Loc.Size = cast<ConstantInt>(II->getArgOperand(1))->getZExtValue();
- break;
- }
- case Intrinsic::arm_neon_vld1: {
- assert(ArgIdx == 0 && "Invalid argument index");
- assert(Loc.Ptr == II->getArgOperand(ArgIdx) &&
- "Intrinsic location pointer not argument?");
- // LLVM's vld1 and vst1 intrinsics currently only support a single
- // vector register.
- if (DL)
- Loc.Size = DL->getTypeStoreSize(II->getType());
- break;
- }
- case Intrinsic::arm_neon_vst1: {
- assert(ArgIdx == 0 && "Invalid argument index");
- assert(Loc.Ptr == II->getArgOperand(ArgIdx) &&
- "Intrinsic location pointer not argument?");
- if (DL)
- Loc.Size = DL->getTypeStoreSize(II->getArgOperand(1)->getType());
- break;
- }
+ return ArgIdx ? Ref : Mod;
}
// We can bound the aliasing properties of memset_pattern16 just as we can
// for memcpy/memset. This is particularly important because the
// LoopIdiomRecognizer likes to turn loops into calls to memset_pattern16
// whenever possible.
- else if (CS.getCalledFunction() &&
- isMemsetPattern16(CS.getCalledFunction(), TLI)) {
+ if (CS.getCalledFunction() &&
+ isMemsetPattern16(CS.getCalledFunction(), *TLI)) {
assert((ArgIdx == 0 || ArgIdx == 1) &&
"Invalid argument index for memset_pattern16");
- if (ArgIdx == 1)
- Loc.Size = 16;
- else if (const ConstantInt *LenCI =
- dyn_cast<ConstantInt>(CS.getArgument(2)))
- Loc.Size = LenCI->getZExtValue();
- assert(Loc.Ptr == CS.getArgument(ArgIdx) &&
- "memset_pattern16 location pointer not argument?");
- Mask = ArgIdx ? Ref : Mod;
+ return ArgIdx ? Ref : Mod;
}
// FIXME: Handle memset_pattern4 and memset_pattern8 also.
- return Loc;
+ return AliasAnalysis::getArgModRefInfo(CS, ArgIdx);
}
static bool isAssumeIntrinsic(ImmutableCallSite CS) {
@@ -814,7 +767,7 @@ bool BasicAliasAnalysis::doInitialization(Module &M) {
/// simple "address taken" analysis on local objects.
AliasAnalysis::ModRefResult
BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
- const Location &Loc) {
+ const MemoryLocation &Loc) {
assert(notDifferentParent(CS.getInstruction(), Loc.Ptr) &&
"AliasAnalysis query involving multiple functions!");
@@ -850,7 +803,7 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
// is impossible to alias the pointer we're checking. If not, we have to
// assume that the call could touch the pointer, even though it doesn't
// escape.
- if (!isNoAlias(Location(*CI), Location(Object))) {
+ if (!isNoAlias(MemoryLocation(*CI), MemoryLocation(Object))) {
PassedAsArg = true;
break;
}
@@ -902,8 +855,8 @@ aliasSameBasePointerGEPs(const GEPOperator *GEP1, uint64_t V1Size,
// If we don't know the size of the accesses through both GEPs, we can't
// determine whether the struct fields accessed can't alias.
- if (V1Size == AliasAnalysis::UnknownSize ||
- V2Size == AliasAnalysis::UnknownSize)
+ if (V1Size == MemoryLocation::UnknownSize ||
+ V2Size == MemoryLocation::UnknownSize)
return AliasAnalysis::MayAlias;
ConstantInt *C1 =
@@ -1017,8 +970,9 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
// derived pointer.
if (const GEPOperator *GEP2 = dyn_cast<GEPOperator>(V2)) {
// Do the base pointers alias?
- AliasResult BaseAlias = aliasCheck(UnderlyingV1, UnknownSize, AAMDNodes(),
- UnderlyingV2, UnknownSize, AAMDNodes());
+ AliasResult BaseAlias =
+ aliasCheck(UnderlyingV1, MemoryLocation::UnknownSize, AAMDNodes(),
+ UnderlyingV2, MemoryLocation::UnknownSize, AAMDNodes());
// Check for geps of non-aliasing underlying pointers where the offsets are
// identical.
@@ -1109,11 +1063,12 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
// pointer, we know they cannot alias.
// If both accesses are unknown size, we can't do anything useful here.
- if (V1Size == UnknownSize && V2Size == UnknownSize)
+ if (V1Size == MemoryLocation::UnknownSize &&
+ V2Size == MemoryLocation::UnknownSize)
return MayAlias;
- AliasResult R = aliasCheck(UnderlyingV1, UnknownSize, AAMDNodes(),
- V2, V2Size, V2AAInfo);
+ AliasResult R = aliasCheck(UnderlyingV1, MemoryLocation::UnknownSize,
+ AAMDNodes(), V2, V2Size, V2AAInfo);
if (R != MustAlias)
// If V2 may alias GEP base pointer, conservatively returns MayAlias.
// If V2 is known not to alias GEP base pointer, then the two values
@@ -1153,7 +1108,7 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
// greater, we know they do not overlap.
if (GEP1BaseOffset != 0 && GEP1VariableIndices.empty()) {
if (GEP1BaseOffset >= 0) {
- if (V2Size != UnknownSize) {
+ if (V2Size != MemoryLocation::UnknownSize) {
if ((uint64_t)GEP1BaseOffset < V2Size)
return PartialAlias;
return NoAlias;
@@ -1167,7 +1122,8 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
// GEP1 V2
// We need to know that V2Size is not unknown, otherwise we might have
// stripped a gep with negative index ('gep <ptr>, -1, ...).
- if (V1Size != UnknownSize && V2Size != UnknownSize) {
+ if (V1Size != MemoryLocation::UnknownSize &&
+ V2Size != MemoryLocation::UnknownSize) {
if (-(uint64_t)GEP1BaseOffset < V1Size)
return PartialAlias;
return NoAlias;
@@ -1218,8 +1174,9 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
// mod Modulo. Check whether that difference guarantees that the
// two locations do not alias.
uint64_t ModOffset = (uint64_t)GEP1BaseOffset & (Modulo - 1);
- if (V1Size != UnknownSize && V2Size != UnknownSize &&
- ModOffset >= V2Size && V1Size <= Modulo - ModOffset)
+ if (V1Size != MemoryLocation::UnknownSize &&
+ V2Size != MemoryLocation::UnknownSize && ModOffset >= V2Size &&
+ V1Size <= Modulo - ModOffset)
return NoAlias;
// If we know all the variables are positive, then GEP1 >= GEP1BasePtr.
@@ -1302,8 +1259,8 @@ BasicAliasAnalysis::aliasPHI(const PHINode *PN, uint64_t PNSize,
// on corresponding edges.
if (const PHINode *PN2 = dyn_cast<PHINode>(V2))
if (PN2->getParent() == PN->getParent()) {
- LocPair Locs(Location(PN, PNSize, PNAAInfo),
- Location(V2, V2Size, V2AAInfo));
+ LocPair Locs(MemoryLocation(PN, PNSize, PNAAInfo),
+ MemoryLocation(V2, V2Size, V2AAInfo));
if (PN > V2)
std::swap(Locs.first, Locs.second);
// Analyse the PHIs' inputs under the assumption that the PHIs are
@@ -1457,14 +1414,16 @@ BasicAliasAnalysis::aliasCheck(const Value *V1, uint64_t V1Size,
// If the size of one access is larger than the entire object on the other
// side, then we know such behavior is undefined and can assume no alias.
if (DL)
- if ((V1Size != UnknownSize && isObjectSmallerThan(O2, V1Size, *DL, *TLI)) ||
- (V2Size != UnknownSize && isObjectSmallerThan(O1, V2Size, *DL, *TLI)))
+ if ((V1Size != MemoryLocation::UnknownSize &&
+ isObjectSmallerThan(O2, V1Size, *DL, *TLI)) ||
+ (V2Size != MemoryLocation::UnknownSize &&
+ isObjectSmallerThan(O1, V2Size, *DL, *TLI)))
return NoAlias;
// Check the cache before climbing up use-def chains. This also terminates
// otherwise infinitely recursive queries.
- LocPair Locs(Location(V1, V1Size, V1AAInfo),
- Location(V2, V2Size, V2AAInfo));
+ LocPair Locs(MemoryLocation(V1, V1Size, V1AAInfo),
+ MemoryLocation(V2, V2Size, V2AAInfo));
if (V1 > V2)
std::swap(Locs.first, Locs.second);
std::pair<AliasCacheTy::iterator, bool> Pair =
@@ -1511,13 +1470,15 @@ BasicAliasAnalysis::aliasCheck(const Value *V1, uint64_t V1Size,
// accesses is accessing the entire object, then the accesses must
// overlap in some way.
if (DL && O1 == O2)
- if ((V1Size != UnknownSize && isObjectSize(O1, V1Size, *DL, *TLI)) ||
- (V2Size != UnknownSize && isObjectSize(O2, V2Size, *DL, *TLI)))
+ if ((V1Size != MemoryLocation::UnknownSize &&
+ isObjectSize(O1, V1Size, *DL, *TLI)) ||
+ (V2Size != MemoryLocation::UnknownSize &&
+ isObjectSize(O2, V2Size, *DL, *TLI)))
return AliasCache[Locs] = PartialAlias;
AliasResult Result =
- AliasAnalysis::alias(Location(V1, V1Size, V1AAInfo),
- Location(V2, V2Size, V2AAInfo));
+ AliasAnalysis::alias(MemoryLocation(V1, V1Size, V1AAInfo),
+ MemoryLocation(V2, V2Size, V2AAInfo));
return AliasCache[Locs] = Result;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-08-04 08:08:41 +0000