[all-commits] [llvm/llvm-project] a1e897: [RISCV] Strengthen INSERT_SUBVECTOR check in combi...

[Craig Topper via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: a1e89710d9fb8d4eb90083d476bd5d77215a960e
      https://github.com/llvm/llvm-project/commit/a1e89710d9fb8d4eb90083d476bd5d77215a960e
  Author: Craig Topper <craig.topper at sifive.com>
  Date:   2023-04-24 (Mon, 24 Apr 2023)

  Changed paths:
    M llvm/lib/Target/RISCV/RISCVISelLowering.cpp

  Log Message:
  -----------
  [RISCV] Strengthen INSERT_SUBVECTOR check in combineBinOpToReduce.

It's not enough for the vector we're inserting into to be undef.
We also need to be inserting into the lowest subvector.

Spotted by inspection while trying to figure out why this doesn't
work for vp.reduce.fadd.