Make memcpyopt TBAA-aware.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121944 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/MemCpyOptimizer.cpp b/lib/Transforms/Scalar/MemCpyOptimizer.cpp
index 4c487e0..a92e848 100644
--- a/lib/Transforms/Scalar/MemCpyOptimizer.cpp
+++ b/lib/Transforms/Scalar/MemCpyOptimizer.cpp
@@ -688,10 +688,6 @@
ConstantInt *C1 = dyn_cast<ConstantInt>(MDep->getLength());
if (!C1) return false;
- uint64_t DepSize = C1->getValue().getZExtValue();
- if (DepSize < MSize)
- return false;
-
AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
// Verify that the copied-from memory doesn't change in between the two
@@ -716,7 +712,8 @@
// source and dest might overlap. We still want to eliminate the intermediate
// value, but we have to generate a memmove instead of memcpy.
Intrinsic::ID ResultFn = Intrinsic::memcpy;
- if (!AA.isNoAlias(M->getRawDest(), MSize, MDep->getRawSource(), DepSize))
+ if (AA.alias(AA.getLocationForDest(M), AA.getLocationForSource(MDep)) !=
+ AliasAnalysis::NoAlias)
ResultFn = Intrinsic::memmove;
// If all checks passed, then we can transform M.
@@ -795,14 +792,9 @@
bool MemCpyOpt::processMemMove(MemMoveInst *M) {
AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
- // If the memmove is a constant size, use it for the alias query, this allows
- // us to optimize things like: memmove(P, P+64, 64);
- uint64_t MemMoveSize = AliasAnalysis::UnknownSize;
- if (ConstantInt *Len = dyn_cast<ConstantInt>(M->getLength()))
- MemMoveSize = Len->getZExtValue();
-
// See if the pointers alias.
- if (AA.alias(M->getRawDest(), MemMoveSize, M->getRawSource(), MemMoveSize) !=
+ if (AA.alias(AA.getLocationForDest(M),
+ AA.getLocationForSource(M)) !=
AliasAnalysis::NoAlias)
return false;