[all-commits] [llvm/llvm-project] 2b24e7: [RISCV] Use tail agnostic policy more often when l...

[Luke Lau via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 2b24e7b5f7bb316317ae4f92347516087348aceb
      https://github.com/llvm/llvm-project/commit/2b24e7b5f7bb316317ae4f92347516087348aceb
  Author: Luke Lau <luke at igalia.com>
  Date:   2023-04-06 (Thu, 06 Apr 2023)

  Changed paths:
    M llvm/lib/Target/RISCV/RISCVISelLowering.cpp
    M llvm/test/CodeGen/RISCV/rvv/active_lane_mask.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vector-fptrunc-vp.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vector-trunc-vp.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-extload-truncstore.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-fp-conv.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-fp2i.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-i2fp.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-insert-subvector.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-insert.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int-exttrunc.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-masked-gather.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-reduction-int-vp.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-setcc-fp-vp.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-setcc-int-vp.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-vpgather.ll
    M llvm/test/CodeGen/RISCV/rvv/shuffle-reverse.ll
    M llvm/test/CodeGen/RISCV/rvv/vector-interleave-fixed.ll

  Log Message:
  -----------
  [RISCV] Use tail agnostic policy more often when lowering insert_subvector

If we're inserting a fixed length subvector into a fixed length vector,
then we can use a tail agnostic policy as long as we're inserting up to
or past the end of the main vector.
I.e., because we're overwriting all of the main vector's tail elements,
and we don't care what the elements after that are.
As noted by Philip in https://reviews.llvm.org/D146711#4220341

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D147347