[PATCH] D58597: [X86] Merge ISD::ADD/SUB nodes into X86ISD::ADD/SUB equivalents (PR40483)

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon created this revision.
RKSimon added reviewers: craig.topper, spatel, niravd.
Herald added a project: LLVM.

Avoid ADD/SUB instruction duplication by reusing the X86ISD::ADD/SUB results.

Includes ADD commutation - I tried to include NEG+SUB SUB commutation as well but this causes regressions as we don't have good combine coverage to simplify X86ISD::SUB.


Repository:
  rL LLVM

https://reviews.llvm.org/D58597

Files:
  lib/Target/X86/X86ISelLowering.cpp
  test/CodeGen/X86/combine-adc.ll
  test/CodeGen/X86/combine-sbb.ll

-------------- next part --------------
A non-text attachment was scrubbed...
Name: D58597.188091.patch
Type: text/x-patch
Size: 7881 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20190224/d4cfab55/attachment.bin>