[clang] [llvm] [NVPTX] Add ex2.approx bf16 support and cleanup intrinsic definition (PR #165446)

[Alex MacLean via cfe-commits]

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@@ -375,28 +375,28 @@ static Value *MakeCpAsync(unsigned IntrinsicID, unsigned IntrinsicIDS,
                                        CGF.EmitScalarExpr(E->getArg(1))});
 }
 
-static Value *MakeHalfType(unsigned IntrinsicID, unsigned BuiltinID,
-                           const CallExpr *E, CodeGenFunction &CGF) {
+static bool EnsureNativeHalfSupport(unsigned BuiltinID, const CallExpr *E,
+                                    CodeGenFunction &CGF) {
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AlexMaclean wrote:

I think "Ensure" is more accurate here. The main action this function performs is emitting an error message when f16 support is not present. It's not purely checking support, such that it would make sense to call at a point where f16 support is not already expected. I think "Ensure" conveys side-effects while "Is" implies a simple pure predicate. 

https://github.com/llvm/llvm-project/pull/165446