[PATCH] D100618: [RISCV] Pad v4i1/v2i1/v1i1 stores with 0s to make a full byte.

[Craig Topper via Phabricator via llvm-commits]

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As noted in the FIXME there's a sort of agreement that the any
extra bits stored will be 0.

The generated code is pretty terrible. I was really hoping we
could use a tail undisturbed trick, but tail undisturbed no
longer applies to masked destinations in the current draft
spec.

Fingers crossed that it isn't common to do this. I doubt IR
from clang or the vectorizer would ever create this kind of store.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D100618

Files:
  llvm/lib/Target/RISCV/RISCVISelLowering.cpp
  llvm/test/CodeGen/RISCV/rvv/fixed-vectors-extload-truncstore.ll
  llvm/test/CodeGen/RISCV/rvv/fixed-vectors-extract-subvector.ll
  llvm/test/CodeGen/RISCV/rvv/fixed-vectors-fp-setcc.ll
  llvm/test/CodeGen/RISCV/rvv/fixed-vectors-mask-load-store.ll
  llvm/test/CodeGen/RISCV/rvv/fixed-vectors-mask-splat.ll

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