[clang] [RISCV][sema] Correct the requirement of `vf[|n|w]cvt.f.*` intrinsics (PR #101608)

[Brandon Wu via cfe-commits]

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@@ -2011,9 +2021,15 @@ let ManualCodegen = [{
           RVVConvBuiltinSet<"vfncvt_xu_f_w", "csi", [["Uv", "UvFwu"]]>;
       let OverloadedName = "vfncvt_f" in {
         defm :
-          RVVConvBuiltinSet<"vfncvt_f_x_w", "csi", [["Fv", "Fvwu"]]>;
+          RVVConvBuiltinSet<"vfncvt_f_x_w", "ci", [["Fv", "Fvwu"]]>;
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4vtomat wrote:

I'm a bit confused, the [spec](https://github.com/riscv/riscv-v-spec/blob/master/v-spec.adoc#184-zvfhmin-vector-extension-for-minimal-half-precision-floating-point) says `When the Zvfhmin extension is implemented, the vfwcvt.f.f.v and vfncvt.f.f.w instructions become defined when SEW=16. `. Does it mean we `zvfhmin` only supports those 2 version of conversion, or it means those 2 version are included?

https://github.com/llvm/llvm-project/pull/101608