[all-commits] [llvm/llvm-project] 974f00: [AArch64][SVE] Fold constant multiply of element c...

[Cullen Rhodes via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 974f00a4369371fae9d25477753c0f68f331e05a
      https://github.com/llvm/llvm-project/commit/974f00a4369371fae9d25477753c0f68f331e05a
  Author: Cullen Rhodes <cullen.rhodes at arm.com>
  Date:   2019-12-20 (Fri, 20 Dec 2019)

  Changed paths:
    M llvm/lib/Target/AArch64/AArch64ISelDAGToDAG.cpp
    M llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
    M llvm/lib/Target/AArch64/SVEInstrFormats.td
    M llvm/test/CodeGen/AArch64/sve-intrinsics-counting-elems.ll

  Log Message:
  -----------
  [AArch64][SVE] Fold constant multiply of element count

Summary:
E.g.

  %0 = tail call i64 @llvm.aarch64.sve.cntw(i32 31)
  %mul = mul i64 %0, <const>

Should emit:

  cntw    x0, all, mul #<const>

For <const> in the range 1-16.

Patch by Kerry McLaughlin

Reviewers: sdesmalen, huntergr, dancgr, rengolin, efriedma

Reviewed By: sdesmalen

Subscribers: tschuett, kristof.beyls, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71014