Add test infrastructure for f16 and f128

Update test traits to support `f16` and `f128`, as applicable. Add the
new routines (`fabs` and `copysign` for `f16` and `f128`) to the list of
all operations.

library/compiler-builtins/libm/crates/libm-macros/src/shared.rs

@@ -4,6 +4,13 @@ use std::fmt;
 use std::sync::LazyLock;
 
 const ALL_OPERATIONS_NESTED: &[(FloatTy, Signature, Option<Signature>, &[&str])] = &[
+    (
+        // `fn(f16) -> f16`
+        FloatTy::F16,
+        Signature { args: &[Ty::F16], returns: &[Ty::F16] },
+        None,
+        &["fabsf16"],
+    ),
     (
         // `fn(f32) -> f32`
         FloatTy::F32,
@@ -28,6 +35,20 @@ const ALL_OPERATIONS_NESTED: &[(FloatTy, Signature, Option<Signature>, &[&str])]
             "tgamma", "trunc", "y0", "y1",
         ],
     ),
+    (
+        // `fn(f128) -> f128`
+        FloatTy::F128,
+        Signature { args: &[Ty::F128], returns: &[Ty::F128] },
+        None,
+        &["fabsf128"],
+    ),
+    (
+        // `(f16, f16) -> f16`
+        FloatTy::F16,
+        Signature { args: &[Ty::F16, Ty::F16], returns: &[Ty::F16] },
+        None,
+        &["copysignf16"],
+    ),
     (
         // `(f32, f32) -> f32`
         FloatTy::F32,
@@ -64,6 +85,13 @@ const ALL_OPERATIONS_NESTED: &[(FloatTy, Signature, Option<Signature>, &[&str])]
             "remainder",
         ],
     ),
+    (
+        // `(f128, f128) -> f128`
+        FloatTy::F128,
+        Signature { args: &[Ty::F128, Ty::F128], returns: &[Ty::F128] },
+        None,
+        &["copysignf128"],
+    ),
     (
         // `(f32, f32, f32) -> f32`
         FloatTy::F32,