[all-commits] [llvm/llvm-project] 5886f0: [RISCV] Allow larger offset when matching build_ve...

[Philip Reames via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 5886f0a18342457f142871ef73f40fc27f936d9b
      https://github.com/llvm/llvm-project/commit/5886f0a18342457f142871ef73f40fc27f936d9b
  Author: Philip Reames <preames at rivosinc.com>
  Date:   2025-06-20 (Fri, 20 Jun 2025)

  Changed paths:
    M llvm/lib/Target/RISCV/RISCVISelLowering.cpp
    M llvm/test/CodeGen/RISCV/rvv/active_lane_mask.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-fp-buildvec-bf16.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-fp-buildvec.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int-buildvec.ll
    M llvm/test/CodeGen/RISCV/rvv/fixed-vectors-reduction-int-vp.ll
    M llvm/test/CodeGen/RISCV/rvv/vle_vid-vfcvt.ll

  Log Message:
  -----------
  [RISCV] Allow larger offset when matching build_vector as vid sequence (#144756)

I happened to notice that when legalizing get.active.lane.mask with
large vectors we were materializing via constant pool instead of just
shifting by a constant.

We should probably be doing a full cost comparison for the different
lowering strategies as opposed to our current adhoc heuristics, but the
few cases this regresses seem pretty minor. (Given the reduction in vset
toggles, they might not be regressions at all.)

---------

Co-authored-by: Craig Topper <craig.topper at sifive.com>



To unsubscribe from these emails, change your notification settings at https://github.com/llvm/llvm-project/settings/notifications