LoopIdiom: Add checks to avoid turning memmove into an infinite loop.
I don't think this is possible with the current implementation but that may change eventually.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166877 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/LoopIdiomRecognize.cpp b/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
index 495d403..bc8ae66 100644
--- a/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
+++ b/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
@@ -178,7 +178,7 @@
// Disable loop idiom recognition if the function's name is a common idiom.
StringRef Name = L->getHeader()->getParent()->getName();
- if (Name == "memset" || Name == "memcpy")
+ if (Name == "memset" || Name == "memcpy" || Name == "memmove")
return false;
// The trip count of the loop must be analyzable.
@@ -524,7 +524,7 @@
const SCEVAddRecExpr *LoadEv,
const SCEV *BECount) {
// If we're not allowed to form memcpy, we fail.
- if (!TLI->has(LibFunc::memcpy))
+ if (!TLI->has(LibFunc::memcpy) || !TLI->has(LibFunc::memmove))
return false;
LoadInst *LI = cast<LoadInst>(SI->getValueOperand());