[all-commits] [llvm/llvm-project] 26e742: [x86][CGP] improve sinking of splatted vector shif...

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  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 26e742fd848b27ff925eab23e4d2a5675b418721
      https://github.com/llvm/llvm-project/commit/26e742fd848b27ff925eab23e4d2a5675b418721
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2020-05-14 (Thu, 14 May 2020)

  Changed paths:
    M llvm/lib/CodeGen/CodeGenPrepare.cpp
    M llvm/lib/Target/X86/X86ISelLowering.cpp
    M llvm/test/CodeGen/X86/vector-shift-by-select-loop.ll
    M llvm/test/Transforms/CodeGenPrepare/X86/vec-shift.ll

  Log Message:
  -----------
  [x86][CGP] improve sinking of splatted vector shift amount operand

Expands on the enablement of the shouldSinkOperands() TLI hook in:
D79718

The last codegen/IR test diff shows what I suspected could happen - we were
sinking all splat shift operands into a loop. But that's not what we want in
general; we only want to sink the *shift amount* operand if it is a splat.

Differential Revision: https://reviews.llvm.org/D79827