simd_fmin/fmax: make semantics and name consistent with scalar intrinsics

Author: RalfJung

example/float-minmax-pass.rs

@@ -33,24 +33,24 @@ fn main() {
     let n = f32x4([nan, nan, nan, nan]);
 
     unsafe {
-        let min0 = simd_fmin(x, y);
-        let min1 = simd_fmin(y, x);
+        let min0 = simd_minimum_number_nsz(x, y);
+        let min1 = simd_minimum_number_nsz(y, x);
         assert_eq!(min0.into_array(), min1.into_array());
         let e = f32x4([1.0, 1.0, 3.0, 3.0]);
         assert_eq!(min0.into_array(), e.into_array());
-        let minn = simd_fmin(x, n);
+        let minn = simd_minimum_number_nsz(x, n);
         assert_eq!(minn.into_array(), x.into_array());
-        let minn = simd_fmin(y, n);
+        let minn = simd_minimum_number_nsz(y, n);
         assert_eq!(minn.into_array(), y.into_array());
 
-        let max0 = simd_fmax(x, y);
-        let max1 = simd_fmax(y, x);
+        let max0 = simd_maximum_number_nsz(x, y);
+        let max1 = simd_maximum_number_nsz(y, x);
         assert_eq!(max0.into_array(), max1.into_array());
         let e = f32x4([2.0, 2.0, 4.0, 4.0]);
         assert_eq!(max0.into_array(), e.into_array());
-        let maxn = simd_fmax(x, n);
+        let maxn = simd_maximum_number_nsz(x, n);
         assert_eq!(maxn.into_array(), x.into_array());
-        let maxn = simd_fmax(y, n);
+        let maxn = simd_maximum_number_nsz(y, n);
         assert_eq!(maxn.into_array(), y.into_array());
     }
 }

src/intrinsics/simd.rs

@@ -493,7 +493,7 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
             }
         }
 
-        sym::simd_fmin | sym::simd_fmax => {
+        sym::simd_minimum_number_nsz | sym::simd_maximum_number_nsz => {
             intrinsic_args!(fx, args => (x, y); intrinsic);
 
             if !x.layout().ty.is_simd() {
@@ -508,8 +508,12 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
                     _ => unreachable!("{:?}", lane_ty),
                 }
                 match intrinsic {
-                    sym::simd_fmin => crate::num::codegen_float_min(fx, x_lane, y_lane),
-                    sym::simd_fmax => crate::num::codegen_float_max(fx, x_lane, y_lane),
+                    sym::simd_minimum_number_nsz => {
+                        crate::num::codegen_float_min(fx, x_lane, y_lane)
+                    }
+                    sym::simd_maximum_number_nsz => {
+                        crate::num::codegen_float_max(fx, x_lane, y_lane)
+                    }
                     _ => unreachable!(),
                 }
             });

src/num.rs

@@ -500,8 +500,8 @@ fn codegen_ptr_binop<'tcx>(
 
 // In Rust floating point min and max don't propagate NaN (not even SNaN). In Cranelift they do
 // however. For this reason it is necessary to use `a.is_nan() ? b : (a >= b ? b : a)` for
-// `minnumf*` and `a.is_nan() ? b : (a <= b ? b : a)` for `maxnumf*`. NaN checks are done by
-// comparing a float against itself. Only in case of NaN is it not equal to itself.
+// `minimum_number_nsz` and `a.is_nan() ? b : (a <= b ? b : a)` for `maximum_number_nsz`. NaN checks
+// are done by comparing a float against itself. Only in case of NaN is it not equal to itself.
 pub(crate) fn codegen_float_min(fx: &mut FunctionCx<'_, '_, '_>, a: Value, b: Value) -> Value {
     // FIXME(bytecodealliance/wasmtime#8312): Replace with Cranelift `fcmp` once
     // `f16`/`f128` backend lowerings have been added to Cranelift.