[PATCH] D25862: X86: Improve BT instruction selection for 64-bit values.

[Simon Pilgrim via llvm-commits]

RKSimon added inline comments.


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Comment at: llvm/lib/Target/X86/X86ISelLowering.cpp:15317
+    DAG.computeKnownBits(BitNo, Zeros, Ones);
+    if (Zeros[5])
+      Src = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, Src);
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Would this be cleaner with DAG.MaskedValueIsZero()?


https://reviews.llvm.org/D25862