[PATCH] D20965: [X86][SSE] Add general lowering of nontemporal vector loads

[Simon Pilgrim via llvm-commits]

RKSimon created this revision.
RKSimon added reviewers: mkuper, craig.topper, spatel, andreadb.
RKSimon added a subscriber: llvm-commits.
RKSimon set the repository for this revision to rL LLVM.

Currently the only way to use the (V)MOVNTDQA nontemporal vector loads instructions is through the int_x86_sse41_movntdqa style builtins.

This patch adds support for lowering nontemporal loads from general IR, allowing us to remove the movntdqa builtins in a future patch.

We currently still fold nontemporal loads into suitable instructions, we should probably look at removing this (and nontemporal stores as well) or at least make the target's folding implementation aware that its dealing with a nontemporal memory transaction.

There is also an issue that VMOVNTDQA only acts on 128-bit vectors on pre-AVX2 hardware - so currently a normal ymm load is still used on AVX1 targets.

Repository:
  rL LLVM

http://reviews.llvm.org/D20965

Files:
  include/llvm/Target/TargetSelectionDAG.td
  lib/Target/X86/X86FastISel.cpp
  lib/Target/X86/X86InstrAVX512.td
  lib/Target/X86/X86InstrSSE.td
  test/CodeGen/X86/fast-isel-nontemporal.ll
  test/CodeGen/X86/nontemporal-loads.ll

-------------- next part --------------
A non-text attachment was scrubbed...
Name: D20965.59559.patch
Type: text/x-patch
Size: 53274 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20160603/f680e863/attachment.bin>