[PATCH] D140048: [RISCV][InsertVSETVLI] Mutate prior vsetvli AVL if doing so allows us to remove a toggle

[Philip Reames via Phabricator via llvm-commits]

reames created this revision.
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This extends the backwards walk to allow mutating the previous vsetvl's AVL value if it was not used by any instructions in between.  In practice, this mostly benefits vmv.x.s and fvmv.f.s patterns since vector instructions which ignore VL are rare.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D140048

Files:
  llvm/lib/Target/RISCV/RISCVInsertVSETVLI.cpp
  llvm/test/CodeGen/RISCV/rvv/fixed-vector-shuffle-reverse.ll
  llvm/test/CodeGen/RISCV/rvv/fixed-vectors-masked-gather.ll
  llvm/test/CodeGen/RISCV/rvv/fixed-vectors-reduction-fp.ll
  llvm/test/CodeGen/RISCV/rvv/fixed-vectors-reduction-int.ll
  llvm/test/CodeGen/RISCV/rvv/vreductions-int-vp.ll
  llvm/test/CodeGen/RISCV/rvv/vreductions-int.ll

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