[all-commits] [llvm/llvm-project] 2a1716: [LegalizeTypes][VP] Widen load/store of fixed leng...

[Luke Lau via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 2a1716dec57e8b3dd668df17ecbedfc77a4112e5
      https://github.com/llvm/llvm-project/commit/2a1716dec57e8b3dd668df17ecbedfc77a4112e5
  Author: Luke Lau <luke at igalia.com>
  Date:   2023-06-12 (Mon, 12 Jun 2023)

  Changed paths:
    M llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-abs.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-extract.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-fp.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.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int-buildvec.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int-splat.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-interleaved-access.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-load.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-store.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-strided-load-combine.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-vselect.ll

  Log Message:
  -----------
  [LegalizeTypes][VP] Widen load/store of fixed length vectors to VP ops

If we have a load/store with an illegal fixed length vector result type that
needs widened, e.g. `x:v6i32 = load p`
Instead of just widening it to: `x:v8i32 = load p`
We can widen it to the equivalent VP operation and set the EVL to the
exact number of elements needed: `x:v8i32 = vp_load a, b, mask=true, evl=6`
Provided that the target supports vp_load/vp_store on the widened type.

Scalable vectors are already widened this way where possible, so this
largely reuses the same logic.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D148713