[PATCH] D93995: [InstSimplify] Fold division by zero to poison

[Nikita Popov via Phabricator via llvm-commits]

nikic created this revision.
nikic added reviewers: aqjune, spatel, lebedev.ri.
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Div/rem by zero is immediate undefined behavior and anything goes. Currently we fold it to undef, this patch changes it to fold to poison instead, which is slightly stronger.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D93995

Files:
  llvm/lib/Analysis/InstructionSimplify.cpp
  llvm/test/Transforms/InstCombine/add-shl-sdiv-to-srem.ll
  llvm/test/Transforms/InstCombine/div.ll
  llvm/test/Transforms/InstCombine/icmp-div-constant.ll
  llvm/test/Transforms/InstCombine/inselt-binop-inseltpoison.ll
  llvm/test/Transforms/InstCombine/inselt-binop.ll
  llvm/test/Transforms/InstCombine/rem.ll
  llvm/test/Transforms/InstCombine/sdiv-exact-by-negative-power-of-two.ll
  llvm/test/Transforms/InstCombine/sdiv-exact-by-power-of-two.ll
  llvm/test/Transforms/InstCombine/shift.ll
  llvm/test/Transforms/InstCombine/vector-udiv.ll
  llvm/test/Transforms/InstCombine/vector-urem.ll
  llvm/test/Transforms/InstSimplify/div.ll
  llvm/test/Transforms/InstSimplify/rem.ll
  llvm/test/Transforms/InstSimplify/undef.ll
  llvm/test/Transforms/SLPVectorizer/X86/alternate-int-inseltpoison.ll

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