[all-commits] [llvm/llvm-project] d042f2: [InstSimplify] Fold call null/undef to poison

[Nikita Popov via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: d042f2db5bf0a852bdbef53ab0310d363031f56f
      https://github.com/llvm/llvm-project/commit/d042f2db5bf0a852bdbef53ab0310d363031f56f
  Author: Nikita Popov <nikita.ppv at gmail.com>
  Date:   2021-01-06 (Wed, 06 Jan 2021)

  Changed paths:
    M llvm/lib/Analysis/InstructionSimplify.cpp
    M llvm/test/Transforms/GVN/PRE/volatile.ll
    M llvm/test/Transforms/InstSimplify/call.ll
    M llvm/test/Transforms/InstSimplify/undef.ll

  Log Message:
  -----------
  [InstSimplify] Fold call null/undef to poison

Calling null or undef results in immediate undefined behavior.
Return poison instead of undef in this case, similar to what
we do for immediate UB due to division by zero.