[clang] [llvm] [HLSL][DirectX][SPIRV] Implement the `fma` API (PR #185304)

[via cfe-commits]

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@@ -2192,9 +2195,8 @@ checkMathBuiltinElementType(Sema &S, SourceLocation Loc, QualType ArgTy,
     break;
   case Sema::EltwiseBuiltinArgTyRestriction::FloatTy:
     if (!EltTy->isRealFloatingType()) {
-      return S.Diag(Loc, diag::err_builtin_invalid_arg_type)
-             << ArgOrdinal << /* scalar or vector */ 5 << /* no int */ 0
-             << /* floating-point */ 1 << ArgTy;
+      return S.Diag(Loc, diag::err_builtin_requires_any_fp_type)
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NeKon69 wrote:

This is so much more hassle than i expected.. especially the "type/types" in `err_builtin_invalid_arg_type` it uses very weird detection on whether you are supposed to have it "types" as in multiple types, or just "type". ill talk about this later in the future PR i guess..

https://github.com/llvm/llvm-project/pull/185304