[all-commits] [llvm/llvm-project] 280044: [RISCV] Refine cost on Min/Max reduction (#79402)

[Shih-Po Hung via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 2800448f88cbc83f688f7848d6ebce247962bd19
      https://github.com/llvm/llvm-project/commit/2800448f88cbc83f688f7848d6ebce247962bd19
  Author: Shih-Po Hung <shihpo.hung at sifive.com>
  Date:   2024-01-30 (Tue, 30 Jan 2024)

  Changed paths:
    M llvm/lib/Target/RISCV/RISCVTargetTransformInfo.cpp
    M llvm/test/Analysis/CostModel/RISCV/reduce-max.ll
    M llvm/test/Analysis/CostModel/RISCV/reduce-min.ll
    M llvm/test/Analysis/CostModel/RISCV/reduce-scalable-fp.ll
    M llvm/test/Analysis/CostModel/RISCV/reduce-scalable-int.ll

  Log Message:
  -----------
  [RISCV] Refine cost on Min/Max reduction (#79402)

This patch is split off from #77342, and follows #79103

- Correct for CodeSize cost that 1 instruction is not included. 3 is
from {VMV.S, ReductionOp, VMV.X}
- Add SplitCost which chains a series of VMAX/VMIN/... which scales with
LMUL.
- Use MVT to estimate VL.