[llvm] [X86] Enable bfloat type support in inline assembly constraints (PR #68469)

[Simon Pilgrim via llvm-commits]

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@@ -56904,6 +56904,10 @@ X86TargetLowering::getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
         if (!Subtarget.hasFP16())
           break;
         [[fallthrough]];
+      case MVT::v8bf16:
+        if (!Subtarget.hasBF16())
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RKSimon wrote:

Are multiple fallthroughs going to work? What happens for a subtarget that supports FP16 but not BF16?

https://github.com/llvm/llvm-project/pull/68469