[PATCH] D87502: [DAGCombiner] Use known bits to fold extract_vector_elt with const index

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:17887
+    APInt DemandedElts = APInt::getOneBitSet(NumElts, IndexC->getZExtValue());
+    KnownBits Known = DAG.computeKnownBits(VecOp, DemandedElts);
+    if (Known.isConstant()) {
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Would this be better handled by SimplifyDemandedBits?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D87502/new/

https://reviews.llvm.org/D87502