[all-commits] [llvm/llvm-project] 6c607c: [RISCV] Preserve tail agnostic policy in foldVMV_V...

[Luke Lau via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 6c607cfb2c2d8acd2b92d7ed8106ab1e4fc0d79d
      https://github.com/llvm/llvm-project/commit/6c607cfb2c2d8acd2b92d7ed8106ab1e4fc0d79d
  Author: Luke Lau <luke at igalia.com>
  Date:   2024-09-04 (Wed, 04 Sep 2024)

  Changed paths:
    M llvm/lib/Target/RISCV/RISCVVectorPeephole.cpp
    M llvm/test/CodeGen/RISCV/rvv/vmv.v.v-peephole.mir

  Log Message:
  -----------
  [RISCV] Preserve tail agnostic policy in foldVMV_V_V (#105788)

This patch helps avoid regressions in an upcoming patch by making sure
we don't accidentally lose a tail agnostic policy when folding a vmv.v.v
into its source.

The previous comment about RISCVInsertVSETVLI relaxing the policy didn't
take into account the fact that there's a policy operand on vmv.v.v,
which can be tail agnostic.

If the tail is agnostic (via either the policy operand or the passthru
being undef) and vmv.v.v's VL <= Src's VL, then Src's tail can be made
agnostic.



To unsubscribe from these emails, change your notification settings at https://github.com/llvm/llvm-project/settings/notifications