[all-commits] [llvm/llvm-project] 433897: [InstCombine][X86] simplifyX86immShift - convert v...

[Simon Pilgrim via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 433897da4abd103a3b72f6c505a2807ab148665a
      https://github.com/llvm/llvm-project/commit/433897da4abd103a3b72f6c505a2807ab148665a
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2020-03-19 (Thu, 19 Mar 2020)

  Changed paths:
    M llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
    M llvm/test/Transforms/InstCombine/X86/x86-vector-shifts.ll

  Log Message:
  -----------
  [InstCombine][X86] simplifyX86immShift - convert variable in-range vector shift by immediate amounts to generic shifts (PR40391)

The slli/srli/srai 'immediate' vector shifts (although its not immediate anymore to match gcc) can be replaced with generic shifts if the shift amount is known to be in range.