Merge pull request rust-lang#224 from rust-lang/feature/min-max-intrinsic

Use intrinsic for min/max

Author: calebzulawski

crates/core_simd/src/intrinsics.rs

@@ -46,6 +46,10 @@ extern "platform-intrinsic" {
     /// fabs
     pub(crate) fn simd_fabs<T>(x: T) -> T;
 
+    // minnum/maxnum
+    pub(crate) fn simd_fmin<T>(x: T, y: T) -> T;
+    pub(crate) fn simd_fmax<T>(x: T, y: T) -> T;
+
     pub(crate) fn simd_eq<T, U>(x: T, y: T) -> U;
     pub(crate) fn simd_ne<T, U>(x: T, y: T) -> U;
     pub(crate) fn simd_lt<T, U>(x: T, y: T) -> U;

crates/core_simd/src/vector/float.rs

@@ -141,11 +141,7 @@ macro_rules! impl_float_vector {
             #[inline]
             #[must_use = "method returns a new vector and does not mutate the original value"]
             pub fn min(self, other: Self) -> Self {
-                // TODO consider using an intrinsic
-                self.is_nan().select(
-                    other,
-                    self.lanes_ge(other).select(other, self)
-                )
+                unsafe { intrinsics::simd_fmin(self, other) }
             }
 
             /// Returns the maximum of each lane.
@@ -154,11 +150,7 @@ macro_rules! impl_float_vector {
             #[inline]
             #[must_use = "method returns a new vector and does not mutate the original value"]
             pub fn max(self, other: Self) -> Self {
-                // TODO consider using an intrinsic
-                self.is_nan().select(
-                    other,
-                    self.lanes_le(other).select(other, self)
-                )
+                unsafe { intrinsics::simd_fmax(self, other) }
             }
 
             /// Restrict each lane to a certain interval unless it is NaN.