[PATCH] D153432: [SDAGBuilder] Handle multi-part arguments in argument copy elision (PR63430)

[Phoebe Wang via Phabricator via llvm-commits]

pengfei added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:10928
+      for (EVT VT : ValueVTs)
+        NumParts += TLI->getNumRegistersForCallingConv(*CurDAG->getContext(),
+                                                       F.getCallingConv(), VT);
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nikic wrote:
> arsenm wrote:
> > For some reason this is split into two hooks for the register type and the number of registers. Wouldn't you need to account for the split and promoted / demoted case?
> Not sure which case you have in mind here, but this is doing the same as the code below (line 10954).
IIUC, we cannot assume all `ValueVTs` are the same VT. So it doesn't look correct to sum them together.
How about iterate Ins[i] and check for `isSplitEnd`?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D153432/new/

https://reviews.llvm.org/D153432