[llvm] [PowerPC] Support conversion between f16 and f128 (PR #130158)

[Lei Huang via llvm-commits]

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@@ -223,13 +223,19 @@ PPCTargetLowering::PPCTargetLowering(const PPCTargetMachine &TM,
     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i8, Expand);
   }
 
+  setTruncStoreAction(MVT::f128, MVT::f16, Expand);
+  setOperationAction(ISD::FP_TO_FP16, MVT::f128, Expand);
+
   if (Subtarget.isISA3_0()) {
+    setLoadExtAction(ISD::EXTLOAD, MVT::f128, MVT::f16, Legal);
     setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f16, Legal);
     setLoadExtAction(ISD::EXTLOAD, MVT::f32, MVT::f16, Legal);
     setTruncStoreAction(MVT::f64, MVT::f16, Legal);
     setTruncStoreAction(MVT::f32, MVT::f16, Legal);
   } else {
     // No extending loads from f16 or HW conversions back and forth.
+    setLoadExtAction(ISD::EXTLOAD, MVT::f128, MVT::f16, Expand);
+    setOperationAction(ISD::FP16_TO_FP, MVT::f128, Expand);
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lei137 wrote:

This sets the action for `ISD::FP16_TO_FP`, the one above is for `ISD::FP_TO_FP16`.

https://github.com/llvm/llvm-project/pull/130158