[all-commits] [llvm/llvm-project] 46b9f1: [AArch64][SVE] Add intrinsics for non-temporal sca...

[Andrzej Warzyński via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 46b9f14d712d47fa0bebd72edd8cfe58cae11f53
      https://github.com/llvm/llvm-project/commit/46b9f14d712d47fa0bebd72edd8cfe58cae11f53
  Author: Andrzej Warzynski <andrzej.warzynski at arm.com>
  Date:   2020-03-12 (Thu, 12 Mar 2020)

  Changed paths:
    M llvm/include/llvm/IR/IntrinsicsAArch64.td
    M llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
    M llvm/lib/Target/AArch64/AArch64ISelDAGToDAG.cpp
    M llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
    M llvm/lib/Target/AArch64/AArch64ISelLowering.h
    M llvm/lib/Target/AArch64/AArch64SVEInstrInfo.td
    M llvm/lib/Target/AArch64/SVEInstrFormats.td
    A llvm/test/CodeGen/AArch64/sve2-intrinsics-nt-gather-loads-64bit-scaled-offset.ll
    A llvm/test/CodeGen/AArch64/sve2-intrinsics-nt-scatter-stores-64bit-scaled-offset.ll

  Log Message:
  -----------
  [AArch64][SVE] Add intrinsics for non-temporal scatters/gathers

Summary:
This patch adds the following intrinsics for non-temporal gather loads
and scatter stores:
  * aarch64_sve_ldnt1_gather_index
  * aarch64_sve_stnt1_scatter_index
These intrinsics implement the "scalar + vector of indices" addressing
mode.

As opposed to regular and first-faulting gathers/scatters, there's no
instruction that would take indices and then scale them. Instead, the
indices for non-temporal gathers/scatters are scaled before the
intrinsics are lowered to `ldnt1` instructions.

The new ISD nodes, GLDNT1_INDEX and SSTNT1_INDEX, are only used as
placeholders so that we can easily identify the cases implemented in
this patch in performGatherLoadCombine and performScatterStoreCombined.
Once encountered, they are replaced with:
  * GLDNT1_INDEX -> SPLAT_VECTOR + SHL + GLDNT1
  * SSTNT1_INDEX -> SPLAT_VECTOR + SHL + SSTNT1

The patterns for lowering ISD::SHL for scalable vectors (required by
this patch) were missing, so these are added too.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D75601