[PATCH] D150967: [MemCpyOpt] precommit test for memcpy removal for immutable arguments from attributes (NFC)

[Kohei Asano via Phabricator via llvm-commits]

khei4 added a comment.

> In this case, the original pointer (%val1) is dereferenceable to 4 bytes, but the new one (%val) is only known dereferenceable to 1 byte, so we are replacing dereferencable(bigger) with dereferenceable(smaller), no? That wouldn't be valid.

Yeah. As you said not only memcpy length and alloca size, but the new pointer's dereferenceability matters. Yeah, if %val1's dereferenceablity is shown in someway(although I'm not sure alloca can be ensured dereferenceable without initializer), that'll be a problem! Thanks! But anyway currently these case seem a little far from a practical case!


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D150967/new/

https://reviews.llvm.org/D150967