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
diff --git a/lib/Analysis/MemoryDependenceAnalysis.cpp b/lib/Analysis/MemoryDependenceAnalysis.cpp
index f4531e0..60fe15f 100644
--- a/lib/Analysis/MemoryDependenceAnalysis.cpp
+++ b/lib/Analysis/MemoryDependenceAnalysis.cpp
@@ -186,15 +186,17 @@
}
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 @@
// 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 @@
// 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)) {
diff --git a/lib/Transforms/Scalar/GVN.cpp b/lib/Transforms/Scalar/GVN.cpp
index 1b42c6b..ceb57f8 100644
--- a/lib/Transforms/Scalar/GVN.cpp
+++ b/lib/Transforms/Scalar/GVN.cpp
@@ -1187,10 +1187,9 @@
return V;
}
-static bool isLifetimeStartOrEnd(Instruction *Inst) {
+static bool isLifetimeStart(Instruction *Inst) {
if (IntrinsicInst* II = dyn_cast<IntrinsicInst>(Inst))
- return II->getIntrinsicID() == Intrinsic::lifetime_start ||
- II->getIntrinsicID() == Intrinsic::lifetime_end;
+ return II->getIntrinsicID() == Intrinsic::lifetime_start;
return false;
}
@@ -1262,8 +1261,8 @@
// Loading the allocation -> undef.
if (isa<AllocaInst>(DepInst) || isMalloc(DepInst) ||
- // Loading immediately after lifetime begin or end -> undef.
- isLifetimeStartOrEnd(DepInst)) {
+ // Loading immediately after lifetime begin -> undef.
+ isLifetimeStart(DepInst)) {
ValuesPerBlock.push_back(AvailableValueInBlock::get(DepBB,
UndefValue::get(LI->getType())));
continue;
@@ -1635,11 +1634,10 @@
return true;
}
- // If this load occurs either right after a lifetime begin or a lifetime end,
+ // If this load occurs either right after a lifetime begin,
// then the loaded value is undefined.
if (IntrinsicInst* II = dyn_cast<IntrinsicInst>(DepInst)) {
- if (II->getIntrinsicID() == Intrinsic::lifetime_start ||
- II->getIntrinsicID() == Intrinsic::lifetime_end) {
+ if (II->getIntrinsicID() == Intrinsic::lifetime_start) {
L->replaceAllUsesWith(UndefValue::get(L->getType()));
toErase.push_back(L);
NumGVNLoad++;