[clang] clang: Remove useFP16ConversionIntrinsics target option (PR #207212)

[Matt Arsenault via cfe-commits]

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@@ -1304,18 +1304,10 @@ mlir::Attribute ConstantEmitter::tryEmitPrivate(const APValue &value,
     return cir::IntAttr::get(ty, value.getInt());
   }
   case APValue::Float: {
-    const llvm::APFloat &init = value.getFloat();
-    if (&init.getSemantics() == &llvm::APFloat::IEEEhalf() &&
-        !cgm.getASTContext().getLangOpts().NativeHalfType &&
-        cgm.getASTContext().getTargetInfo().useFP16ConversionIntrinsics()) {
-      cgm.errorNYI("ConstExprEmitter::tryEmitPrivate half");
-      return {};
-    }
-
     mlir::Type ty = cgm.convertType(destType);
     assert(mlir::isa<cir::FPTypeInterface>(ty) &&
            "expected floating-point type");
-    return cir::FPAttr::get(ty, init);
+    return cir::FPAttr::get(ty, value.getFloat());
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arsenm wrote:

That really ought to have been in the patch that ported this code in the first place. I've added some basic testing, but the ABI coercion seems to mostly be missing on the CIR path so I left that alone 

https://github.com/llvm/llvm-project/pull/207212