Add core_simd/tests/cast.rs

Author: workingjubilee

crates/core_simd/tests/cast.rs

@@ -0,0 +1,37 @@
+#![feature(portable_simd)]
+macro_rules! cast_types {
+    ($start:ident, $($target:ident),*) => {
+        mod $start {
+            use core_simd::simd::Simd;
+            type Vector<const N: usize> = Simd<$start, N>;
+            $(
+                mod $target {
+                    use super::*;
+                    test_helpers::test_lanes! {
+                        fn cast_as<const N: usize>() {
+                            test_helpers::test_unary_elementwise(
+                                &Vector::<N>::cast::<$target>,
+                                &|x| x as $target,
+                                &|_| true,
+                            )
+                        }
+                    }
+                }
+            )*
+        }
+    };
+}
+
+// The hypothesis is that widening conversions aren't terribly interesting.
+cast_types!(f32, f64, i8, u8, usize, isize);
+cast_types!(f64, f32, i8, u8, usize, isize);
+cast_types!(i8, u8, f32);
+cast_types!(u8, i8, f32);
+cast_types!(i16, u16, i8, u8, f32);
+cast_types!(u16, i16, i8, u8, f32);
+cast_types!(i32, u32, i8, u8, f32, f64);
+cast_types!(u32, i32, i8, u8, f32, f64);
+cast_types!(i64, u64, i8, u8, isize, usize, f32, f64);
+cast_types!(u64, i64, i8, u8, isize, usize, f32, f64);
+cast_types!(isize, usize, i8, u8, f32, f64);
+cast_types!(usize, isize, i8, u8, f32, f64);