[Diffusion] rG13ec913bdf50: [InstCombine] Recognize `((x * y) s/ x) !=/== y` as an signed multiplication…

[Craig Topper via Phabricator via llvm-commits]

craig.topper added a comment.

In rG13ec913bdf500e2354cc55bf29e2f5d99e0c709e#1023123 <https://reviews.llvm.org/rG13ec913bdf500e2354cc55bf29e2f5d99e0c709e#1023123>, @rnk wrote:

> In rG13ec913bdf500e2354cc55bf29e2f5d99e0c709e#1022850 <https://reviews.llvm.org/rG13ec913bdf500e2354cc55bf29e2f5d99e0c709e#1022850>, @nickdesaulniers wrote:
>
>> Does D108928 <https://reviews.llvm.org/D108928> help this get re-landed?
>
> Sure, go for it.

I think we would need to remove the MULO libcall support completely by removing the associated code from LegalizeIntegerTypes.cpp and LegalizeDAG.cpp to ensure that there was no way to ever generate the libcall. All we've done so far is fix the cases that @nickdesaulniers and others have found.


BRANCHES
  main, release/13.x

TAGS
  llvmorg-13.0.0-rc1, llvmorg-13.0.0-rc2, llvmorg-14-init

Users:
  lebedev.ri (Author)

https://reviews.llvm.org/rG13ec913bdf50