[PATCH] D137140: [SDAG] Allow scalable vectors in ComputeKnownBits

[Philip Reames via Phabricator via llvm-commits]

reames added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:2956
   case ISD::BUILD_VECTOR:
+    if (Op.getValueType().isScalableVector())
+      break;
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frasercrmck wrote:
> Is this possible? A BUILD_VECTOR with scalable-vector value type?
I vaguely think I've seen this in debug output before, but converting it into an assert didn't catch any failures, and I don't remember the case.  Let's make it an assert and see if anything falls out.  


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:3645
     // computeKnownBits not yet implemented for scalable vectors.
-    if (VecVT.isScalableVector())
+    if (Op.getValueType().isScalableVector() || VecVT.isScalableVector())
       break;
----------------
frasercrmck wrote:
> Can EXTRACT_VECTOR_ELT produce a scalable vector? I'd have thought the existing check was sufficient.
Good catch


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D137140/new/

https://reviews.llvm.org/D137140