[PATCH] D104868: [ARM] Fix crash in chained BFI combine due to incorrectly RAUW'ing a node.

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: llvm/lib/Target/ARM/ARMISelLowering.cpp:14049
+          DCI.DAG.getConstant(NewFromMask.countTrailingZeros(), dl, VT));
+    return DCI.DAG.getNode(ARMISD::BFI, dl, VT, CombineBFI.getOperand(0), From1,
                            DCI.DAG.getConstant(~NewToMask, dl, VT));
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Hang on, I'm not sure this is right.  At least, it's not obviously equivalent.  FindBFIToCombineWith can look through multiple BFI operations.  Not sure if we have proper test coverage for this.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D104868/new/

https://reviews.llvm.org/D104868