[PATCH] D98130: [RISCV] Fold (select_cc (xor X, Y), 0, eq/ne, trueV, falseV) -> (select_cc X, Y, eq/ne, trueV, falseV)

[Craig Topper via Phabricator via llvm-commits]

craig.topper created this revision.
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This pattern occurs when lowering for overflow operations
introduce an xor after select_cc has already been formed.

I had to rework another combine that looked for select_cc of an xor
with 1. That xor will now get combined away so we just need to
look for the RHS of the select_cc being 1.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D98130

Files:
  llvm/lib/Target/RISCV/RISCVISelLowering.cpp
  llvm/test/CodeGen/RISCV/sadd_sat.ll
  llvm/test/CodeGen/RISCV/sadd_sat_plus.ll
  llvm/test/CodeGen/RISCV/ssub_sat.ll
  llvm/test/CodeGen/RISCV/ssub_sat_plus.ll
  llvm/test/CodeGen/RISCV/xaluo.ll

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