[PATCH] D86260: [CodeGen] Postprocess PHI nodes for callbr

[James Y Knight via Phabricator via llvm-commits]

jyknight added inline comments.
Herald added a subscriber: danielkiss.


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:10075
+
+    if (CI) {
+      if (Preprocess) {
----------------
This seems a bit confusing.

I think it would probably be clearer to make the body of this loop into a separate function which handles a single successor BasicBlock. Call that function directly on the default successor from visitCallBr, and move the loop over successors with the callbr default-successor-exclusion into visit().



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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:10150
 
   ConstantsOut.clear();
 }
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This is problematical if we're calling this function multiple times now. A constant will be emitted redundantly, if it's present both in indirect and default successor phi branches. Oddly enough, this is a member variable instead of a local, even though it's only used in this function. I think you can just move this call to clear() to the end of visit(), and that solves the problem.


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  https://reviews.llvm.org/D86260/new/

https://reviews.llvm.org/D86260