Cleanup/remove some parts of the lifetime region handling code in memdep and GVN,

per Chris' comments.  Adjust testcases to match.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90304 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson
2009-12-02 07:35:19 +00:00
parent 720e790480
commit 9ff5a23186
4 changed files with 21 additions and 44 deletions
+13 -16
View File
@@ -186,15 +186,17 @@ getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad,
}
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(Inst)) {
// Debug intrinsics don't cause dependences.
if (isa<DbgInfoIntrinsic>(Inst)) continue;
// If we pass an invariant-end marker, then we've just entered an
// invariant region and can start ignoring dependencies.
if (II->getIntrinsicID() == Intrinsic::invariant_end) {
uint64_t InvariantSize = ~0ULL;
if (ConstantInt *CI = dyn_cast<ConstantInt>(II->getOperand(2)))
InvariantSize = CI->getZExtValue();
AliasAnalysis::AliasResult R =
AA->alias(II->getOperand(3), InvariantSize, MemPtr, MemSize);
// 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->getOperand(3), ~0ULL, MemPtr, ~0ULL);
if (R == AliasAnalysis::MustAlias) {
InvariantTag = II->getOperand(1);
continue;
@@ -202,14 +204,12 @@ getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad,
// If we reach a lifetime begin or end marker, then the query ends here
// because the value is undefined.
} else if (II->getIntrinsicID() == Intrinsic::lifetime_start ||
II->getIntrinsicID() == Intrinsic::lifetime_end) {
uint64_t InvariantSize = ~0ULL;
if (ConstantInt *CI = dyn_cast<ConstantInt>(II->getOperand(1)))
InvariantSize = CI->getZExtValue();
} else if (II->getIntrinsicID() == Intrinsic::lifetime_start) {
// 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->getOperand(2), InvariantSize, MemPtr, MemSize);
AA->alias(II->getOperand(2), ~0ULL, MemPtr, ~0ULL);
if (R == AliasAnalysis::MustAlias)
return MemDepResult::getDef(II);
}
@@ -219,9 +219,6 @@ getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad,
// at this point. Nothing a load depends on can live in an invariant region.
if (isLoad && InvariantTag) continue;
// Debug intrinsics don't cause dependences.
if (isa<DbgInfoIntrinsic>(Inst)) continue;
// Values depend on loads if the pointers are must aliased. This means that
// a load depends on another must aliased load from the same value.
if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) {