[PATCH] D151710: [X86][BF16] Share FP16 vector ABI with BF16

Tue May 30 23:01:33 PDT 2023

pengfei added inline comments.

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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:642
+  // Have a try for bf16 because some targets share its ABI with fp16.
+  if (ValueEVT == MVT::bf16 && PartEVT == MVT::f16)
+    Val = DAG.getNode(ISD::BITCAST, DL,
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RKSimon wrote:
> Do we need  a TLI callback / legality check for f16?
I think not. The `PartVT` comes from `TLI.getRegisterTypeForCallingConv`. We don't need to add another callback and targets use this way should have already made f16 legal.
I can add an `TLI.isTypeLegal(PartVT)` if you wish.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D151710/new/

https://reviews.llvm.org/D151710