[PATCH] D57302: [DAGCombine] More diamong carry pattern optimization.

[Amaury SECHET via Phabricator via llvm-commits]

deadalnix created this revision.
deadalnix added reviewers: hfinkel, RKSimon, craig.topper.

This diff improve the capability of DAGCOmbine to generate linear carries propagation in presence of a diamond pattern. It is now able to match a large variety of different patterns rather than some hardcoded one.

Arguably, the codegen in test cases is not better, but this is to be expected. The goal of this transformation is more about canonicalisation than actual optimisation.


Repository:
  rL LLVM

https://reviews.llvm.org/D57302

Files:
  lib/CodeGen/SelectionDAG/DAGCombiner.cpp
  test/CodeGen/X86/subcarry.ll

-------------- next part --------------
A non-text attachment was scrubbed...
Name: D57302.183757.patch
Type: text/x-patch
Size: 6507 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20190127/f93f023a/attachment.bin>