[PATCH] D23920: [StatepointsForGC] Identify values for rematerialization in presence of PHI

[Philip Reames via llvm-commits]

reames accepted this revision.
reames added a comment.

LGTM w/minor comment


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Comment at: lib/Transforms/Scalar/RewriteStatepointsForGC.cpp:1802
@@ +1801,3 @@
+  // PHI nodes that have the same incoming values, and belonging to the same
+  // basic blocks are essentially the same SSA value.
+  if (PHINode *CurrentPhi = dyn_cast<PHINode>(CurrentValue))
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I think it's important to call out in the comment that this is a workaround for deficiency in the base pointer rewriting code.  That's not immediately obvious to everyone reading.  :)

We really need to rewrite that code at some point.  My initial prototype version has lived far longer than it should have.  


https://reviews.llvm.org/D23920