[all-commits] [llvm/llvm-project] 146dad: [ARM] MVE FP16 cost adjustments

[David Green via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 146dad0077b46a0fb8e158c10490c1774db5a762
      https://github.com/llvm/llvm-project/commit/146dad0077b46a0fb8e158c10490c1774db5a762
  Author: David Green <david.green at arm.com>
  Date:   2020-07-06 (Mon, 06 Jul 2020)

  Changed paths:
    M llvm/lib/Target/ARM/ARMTargetTransformInfo.cpp
    M llvm/test/Analysis/CostModel/ARM/cast_ldst.ll
    M llvm/test/Transforms/LoopVectorize/ARM/prefer-tail-loop-folding.ll

  Log Message:
  -----------
  [ARM] MVE FP16 cost adjustments

This adjusts the MVE fp16 cost model, similar to how we already do for
integer casts. It uses the base cost of 1 per cvt for most fp extend /
truncates, but adjusts it for loads and stores where we know that a
extending load has been used to get the load into the correct lane, and
only an MVE VCVTB is then needed.

Differential Revision: https://reviews.llvm.org/D81813