Fix i586 detection

Author: calebzulawski

crates/core_simd/src/reduction.rs

@@ -55,11 +55,12 @@ macro_rules! impl_float_reductions {
         where
             Self: crate::LanesAtMost64
         {
+
             /// Produces the sum of the lanes of the vector.
             #[inline]
             pub fn sum(self) -> $scalar {
                 // f32 SIMD sum is inaccurate on i586
-                if cfg!(target_arch = "i586") && core::mem::size_of::<$scalar>() == 4 {
+                if cfg!(all(target_arch = "x86", not(target_feature = "sse2"))) && core::mem::size_of::<$scalar>() == 4 {
                     self.as_slice().iter().sum()
                 } else {
                     unsafe { crate::intrinsics::simd_reduce_add_ordered(self, 0.) }
@@ -70,7 +71,7 @@ macro_rules! impl_float_reductions {
             #[inline]
             pub fn product(self) -> $scalar {
                 // f32 SIMD product is inaccurate on i586
-                if cfg!(target_arch = "i586") && core::mem::size_of::<$scalar>() == 4 {
+                if cfg!(all(target_arch = "x86", not(target_feature = "sse2"))) && core::mem::size_of::<$scalar>() == 4 {
                     self.as_slice().iter().product()
                 } else {
                     unsafe { crate::intrinsics::simd_reduce_mul_ordered(self, 1.) }