[PATCH] D75169: [ARM] Supporting lowering of half-precision FP arguments and returns in AArch32's backend

[Eli Friedman via Phabricator via cfe-commits]

efriedma added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:524
+                                      CallConv))
+    return;
   EVT ValueVT = Val.getValueType();
----------------
I'm not sure I understand why the standard getCopyFromParts/getCopyToParts codepath doesn't work. Is the issue that it uses FP_ROUND/FP_EXTEND to promote from f16 to f32?


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Comment at: llvm/lib/Target/ARM/ARMCallingConv.cpp:296
+
+static bool CC_ARM_AAPCS_Custom_f16(unsigned ValNo, MVT ValVT, MVT LocVT,
+                                    CCValAssign::LocInfo LocInfo,
----------------
It isn't obvious to me why you need this; can you not use CCBitConvertToType/CCAssignToReg?


Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D75169/new/

https://reviews.llvm.org/D75169