[PATCH] D97667: [loop-idiom] Hoist loop memcpys to loop preheader

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added inline comments.


================
Comment at: llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp:868-870
+  // Check if the load stride matches the store stride.
+  if (StrIntStride != LoadIntStride && StrIntStride != -LoadIntStride)
+    return false;
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lebedev.ri wrote:
> This doesn't make sense. Strides of load and store must match exactly.
> Doesn't this miscompile the case where load goes forward and store backward or vice verse?
Also, i would like to see better test coverage:
1. negative stride
2. load/store stride sign mismatch 


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D97667/new/

https://reviews.llvm.org/D97667