[PATCH] D115392: [SLP] Don't vectorize div/rem with undef denominators

Simon Pilgrim via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Sat Dec 11 04:52:03 PST 2021


RKSimon added inline comments.


================
Comment at: llvm/test/Transforms/SLPVectorizer/X86/arith-div-undef.ll:16
   %a7 = extractelement <8 x i32> %a, i32 7
   %ab0 = sdiv i32 %a0, undef
   %ab1 = sdiv i32 %a1, 4
----------------
lebedev.ri wrote:
> lebedev.ri wrote:
> > This is an immediate UB https://alive2.llvm.org/ce/z/uKOdmW
> (better link: https://alive2.llvm.org/ce/z/oD8gjC)
Although https://alive2.llvm.org/ce/z/ma3VyM shows that this patch isn't incorrect either


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D115392/new/

https://reviews.llvm.org/D115392



More information about the llvm-commits mailing list