[PATCH] D56011: [x86] lower extracted fadd/fsub to horizontal vector math

[Sanjay Patel via Phabricator via llvm-commits]

spatel created this revision.
spatel added reviewers: andreadb, RKSimon, craig.topper.
Herald added a subscriber: mcrosier.

This would show up if we fix horizontal reductions to narrow as they go along, but it's an improvement for size and/or Jaguar (fast-hops) independent of that.

We need to do this late to not interfere with other pattern matching of larger horizontal sequences.

I'm guessing we would extend this to integer ops too, but I figured I better stop here and get feedback on the initial FP part in case I've missed something.


https://reviews.llvm.org/D56011

Files:
  lib/Target/X86/X86ISelLowering.cpp
  test/CodeGen/X86/haddsub-undef.ll
  test/CodeGen/X86/haddsub.ll

-------------- next part --------------
A non-text attachment was scrubbed...
Name: D56011.179303.patch
Type: text/x-patch
Size: 33399 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20181221/f98a2657/attachment-0001.bin>