[PATCH] D65023: [MS] Pass S_HEAPALLOCSITE metadata through SelectionDAG

[Reid Kleckner via Phabricator via llvm-commits]

rnk added a comment.

We discussed this offline, and after looking at rL364516 <https://reviews.llvm.org/rL364516>, it seems like the side table might be a better way to go.



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Comment at: llvm/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp:789-790
+                                MachineFunction &MF) {
+  // Assume that a MDNodeSDNode operand associated with a call instruction is
+  // heapallocsite metadata.
+  if (NewInsn && NewInsn->isCall()) {
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I don't think we should assume that any metadata node on a call is a heap alloc site.


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:3390-3391
 
       // This is hot code, so optimize the two most common cases of 1 and 2
       // results.
       SDVTList VTList;
----------------
Given that this is hot code, I think we want to avoid scanning operands if possible. Can we only do this for variadic instructions, like calls?


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  https://reviews.llvm.org/D65023/new/

https://reviews.llvm.org/D65023