[all-commits] [llvm/llvm-project] 992113: [RISCV] Optimize select-like vector shuffles

[Fraser Cormack via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 99211352c1ac4b31160ca2381e6c5f87c205b699
      https://github.com/llvm/llvm-project/commit/99211352c1ac4b31160ca2381e6c5f87c205b699
  Author: Fraser Cormack <fraser at codeplay.com>
  Date:   2021-03-25 (Thu, 25 Mar 2021)

  Changed paths:
    M llvm/lib/Target/RISCV/RISCVISelLowering.cpp
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-fp-shuffles.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int-shuffles.ll

  Log Message:
  -----------
  [RISCV] Optimize select-like vector shuffles

This patch adds a small optimization for vector shuffle lowering,
detecting shuffles which can be re-expressed as vector selects.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D99270