[PATCH] D86383: [GlobalISel] Fold xor(cmp(pred, _, _), 1) -> cmp(inverse(pred), _, _)

Matt Arsenault via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Wed Aug 26 16:47:42 PDT 2020


arsenm added inline comments.


================
Comment at: llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp:1994
+  // For i1, Cst will always be -1 regardless of boolean contents.
+  if (!isConstTrueVal(TLI, Cst) && !(Ty == LLT::scalar(1) && Cst == -1))
+    return false;
----------------
Swap the order of these checks?


================
Comment at: llvm/test/CodeGen/AArch64/GlobalISel/prelegalizercombiner-invert-cmp.mir:136
+    RET_ReallyLR implicit $w0
+...
----------------
Test with vectors?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D86383/new/

https://reviews.llvm.org/D86383



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