[all-commits] [llvm/llvm-project] 027516: [RISCV] Verify that policy operands only exist on ...

[Philip Reames via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 027516553da4d380a9a7ea673342dba61318cc47
      https://github.com/llvm/llvm-project/commit/027516553da4d380a9a7ea673342dba61318cc47
  Author: Philip Reames <preames at rivosinc.com>
  Date:   2022-10-06 (Thu, 06 Oct 2022)

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

  Log Message:
  -----------
  [RISCV] Verify that policy operands only exist on instructions with tied passthru operands

This is a non-trivial property relied upon by D135396. I wrote this to convince myself it was true.

Differential Revision: https://reviews.llvm.org/D135403


  Commit: 79f0413e5e3cc775d0c116b66e3ff7fb82f1ee54
      https://github.com/llvm/llvm-project/commit/79f0413e5e3cc775d0c116b66e3ff7fb82f1ee54
  Author: Philip Reames <preames at rivosinc.com>
  Date:   2022-10-06 (Thu, 06 Oct 2022)

  Changed paths:
    M llvm/lib/Target/RISCV/RISCVISelLowering.cpp
    M llvm/test/CodeGen/RISCV/double-convert.ll
    M llvm/test/CodeGen/RISCV/double-round-conv-sat.ll
    M llvm/test/CodeGen/RISCV/float-convert.ll
    M llvm/test/CodeGen/RISCV/float-round-conv-sat.ll
    M llvm/test/CodeGen/RISCV/fpclamptosat.ll
    M llvm/test/CodeGen/RISCV/half-convert.ll
    M llvm/test/CodeGen/RISCV/half-round-conv-sat.ll
    M llvm/test/CodeGen/RISCV/min-max.ll
    M llvm/test/CodeGen/RISCV/rv32zbb-zbkb.ll
    M llvm/test/CodeGen/RISCV/rv64zbb.ll
    M llvm/test/CodeGen/RISCV/uadd_sat.ll
    M llvm/test/CodeGen/RISCV/uadd_sat_plus.ll

  Log Message:
  -----------
  [RISCV] Use branchless form for selects with -1 in either arm

We can lower these as an or with the negative of the condition value. This appears to result in significantly less branch-y code on multiple common idioms (as seen in tests).

Differential Revision: https://reviews.llvm.org/D135316


Compare: https://github.com/llvm/llvm-project/compare/76ac3b89173e...79f0413e5e3c