[PATCH] D54583: PowerPC: Optimize SPE double parameter calling setup

Tue Apr 2 13:13:00 PDT 2019

jhibbits marked 7 inline comments as done.
jhibbits added inline comments.

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Comment at: lib/Target/PowerPC/PPCISelLowering.cpp:3215
+  // Try to get the first register.
+  unsigned Reg = State.AllocateReg(HiRegList, LoRegList);
+  if (!Reg)
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nemanjai wrote:
> I don't really understand why this is handled differently than the parameters in terms of how the allocation is done. It is perhaps a good indicator that a comment explaining the difference would be useful.
Yeah, they're identical, but on second look they shouldn't be.  Return values can only be in R3 and R4, so they should be identical in every way except the register list.

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Comment at: lib/Target/PowerPC/PPCISelLowering.h:1114
     SDValue LowerBITCAST(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerEXTRACT_ELEMENT(SDValue Op, SelectionDAG &DAG) const;

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nemanjai wrote:
> This does not appear to be used. Perhaps an artifact remaining from a previous revision?
Yes, it's an artifact.

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D54583/new/

https://reviews.llvm.org/D54583