[PATCH] D58009: [DAGCombine] Simplify funnel shifts with undef/zero args to bitshifts

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon updated this revision to Diff 186153.
RKSimon retitled this revision from "[DAGCombine] Simplify funnel shifts with undef args to bitshifts" to "[DAGCombine] Simplify funnel shifts with undef/zero args to bitshifts".
RKSimon edited the summary of this revision.
RKSimon added a comment.

Add support for folding cases with zero arguments.

Limited the variable cases to where we know the shift is in range

I'd prefer to deal with the undef shift amounts in a separate patch as that's mostly separate from this fold logic.


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D58009/new/

https://reviews.llvm.org/D58009

Files:
  lib/CodeGen/SelectionDAG/DAGCombiner.cpp
  test/CodeGen/X86/funnel-shift.ll

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