Rollup merge of rust-lang#153884 - folkertdev:f16-classify-runtime-const, r=tgross35

test `classify-runtime-const` for `f16`

tracking issue: rust-lang#116909

r? tgross35

Author: Zalathar

tests/assembly-llvm/asm/aarch64-types.rs

@@ -98,8 +98,8 @@ pub unsafe fn issue_75761() {
 
 macro_rules! check {
     ($func:ident $ty:ident $class:ident $mov:literal $modifier:literal) => {
-        // FIXME(f16_f128): Change back to `$func(x: $ty) -> $ty` once arm64ec can pass and return
-        // `f16` and `f128` without LLVM erroring.
+        // FIXME(f128): Change back to `$func(x: $ty) -> $ty` once arm64ec can pass and return
+        // `f128` without LLVM erroring.
         // LLVM issue: <https://github.com/llvm/llvm-project/issues/94434>
         #[no_mangle]
         pub unsafe fn $func(inp: &$ty, out: &mut $ty) {
@@ -117,7 +117,7 @@ macro_rules! check {
 
 macro_rules! check_reg {
     ($func:ident $ty:ident $reg:tt $mov:literal) => {
-        // FIXME(f16_f128): See FIXME in `check!`
+        // FIXME(f128): See FIXME in `check!`
         #[no_mangle]
         pub unsafe fn $func(inp: &$ty, out: &mut $ty) {
             let x = *inp;

tests/ui/float/classify-runtime-const.rs

@@ -2,7 +2,11 @@
 //@ revisions: opt noopt ctfe
 //@[opt] compile-flags: -O
 //@[noopt] compile-flags: -Zmir-opt-level=0
+//@ min-llvm-version: 22
+//@ compile-flags: --check-cfg=cfg(target_has_reliable_f16)
 // ignore-tidy-linelength
+#![feature(cfg_target_has_reliable_f16_f128)]
+#![cfg_attr(target_has_reliable_f16, feature(f16))]
 
 // This tests the float classification functions, for regular runtime code and for const evaluation.
 
@@ -50,6 +54,13 @@ macro_rules! assert_test {
 
 macro_rules! suite {
     ( $tyname:ident => $( $tt:tt )* ) => {
+        #[cfg(target_has_reliable_f16)]
+        fn f16() {
+            #[allow(unused)]
+            type $tyname = f16;
+            suite_inner!(f16 => $($tt)*);
+        }
+
         fn f32() {
             #[allow(unused)]
             type $tyname = f32;
@@ -121,7 +132,9 @@ suite! { T => // type alias for the type we are testing
 }
 
 fn main() {
+    #[cfg(target_has_reliable_f16)]
+    f16();
     f32();
     f64();
-    // FIXME(f16_f128): also test f16 and f128
+    // FIXME(f128): also test f128
 }