[llvm] [PowerPC] Implement llvm.set.rounding intrinsic (PR #67302)

[Justin Hibbits via llvm-commits]

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@@ -426,6 +426,7 @@ PPCTargetLowering::PPCTargetLowering(const PPCTargetMachine &TM,
     setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f32, Expand);
 
   setOperationAction(ISD::GET_ROUNDING, MVT::i32, Custom);
+  setOperationAction(ISD::SET_ROUNDING, MVT::Other, Custom);
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chmeeedalf wrote:

This won't work for SPE, since SPE doesn't have standard floating point registers.  The equivalent is a move to the SPEFSCR SPR.

https://github.com/llvm/llvm-project/pull/67302