//! SSE2 arithmetic operations (add, sub, mul, div).

#[cfg(target_arch = "x86_64")]

use std::arch::x86_64::*;

/// SSE2 vector addition.

#[inline]

#[target_feature(enable = "sse2")]

pub unsafe fn add(a: &[f32], b: &[f32], result: &mut [f32]) {

    let len = a.len();

    let mut i = 0;

    while i + 4 <= len {

        let va = _mm_loadu_ps(a.as_ptr().add(i));

        let vb = _mm_loadu_ps(b.as_ptr().add(i));

        _mm_storeu_ps(result.as_mut_ptr().add(i), _mm_add_ps(va, vb));

        i += 4;

    }

    for j in i..len { result[j] = a[j] + b[j]; }

}

/// SSE2 vector subtraction.

#[inline]

#[target_feature(enable = "sse2")]

pub unsafe fn sub(a: &[f32], b: &[f32], result: &mut [f32]) {

    let len = a.len();

    let mut i = 0;

    while i + 4 <= len {

        let va = _mm_loadu_ps(a.as_ptr().add(i));

        let vb = _mm_loadu_ps(b.as_ptr().add(i));

        _mm_storeu_ps(result.as_mut_ptr().add(i), _mm_sub_ps(va, vb));

        i += 4;

    }

    for j in i..len { result[j] = a[j] - b[j]; }

}

/// SSE2 vector multiplication.

#[inline]

#[target_feature(enable = "sse2")]

pub unsafe fn mul(a: &[f32], b: &[f32], result: &mut [f32]) {

    let len = a.len();

    let mut i = 0;

    while i + 4 <= len {

        let va = _mm_loadu_ps(a.as_ptr().add(i));

        let vb = _mm_loadu_ps(b.as_ptr().add(i));

        _mm_storeu_ps(result.as_mut_ptr().add(i), _mm_mul_ps(va, vb));

        i += 4;

    }

    for j in i..len { result[j] = a[j] * b[j]; }

}

/// SSE2 vector division.

#[inline]

#[target_feature(enable = "sse2")]

pub unsafe fn div(a: &[f32], b: &[f32], result: &mut [f32]) {

    let len = a.len();

    let mut i = 0;

    while i + 4 <= len {

        let va = _mm_loadu_ps(a.as_ptr().add(i));

        let vb = _mm_loadu_ps(b.as_ptr().add(i));

        _mm_storeu_ps(result.as_mut_ptr().add(i), _mm_div_ps(va, vb));

        i += 4;

    }

    for j in i..len { result[j] = a[j] / b[j]; }

}