_mm_hsub_pd

Microsoft Specific

Generates the hsubpd instruction.

__m128d _mm_hsub_pd(
   __m128d a,
   __m128d b,
);

Parameters

• [in] a
  The first operand.

• [in] b
  The second operand.

Requirements

Header file <intrin.h>

Remarks

The hsubpd instruction performs a horizontal subtract, meaning that adjacent elements in the same operand are subtracted. Each 128-bit argument is considered as two 64-bit floating-point elements, numbered from 0 to 1, with 1 being the high-order element. The result of the operation on operand a {A0, A1} and operand b {B0, B1} is { A0 - A1, B0 - B1 }.

This routine is only available as an intrinsic.

Example

// processor: x86 with SSE3
// Execute the hsub_pd instruction using the intrinsic
// _mm_hsub_pd 

#include <stdio.h>
#include <intrin.h>

#pragma intrinsic ( _mm_hsub_pd )

int main( )
{
    __m128d u, v, w;
    __declspec(align(16)) double a[2] = { 0.5, 0.3 };
    __declspec(align(16)) double b[2] = { 0.005, 0.003 };

    printf_s("Loading double values %e %e into XMM register.\n",
             a[0], a[1] );
    u = _mm_load_pd(a);
    printf_s("Loading double values %e %e into XMM register.\n",
             b[0], b[1] );
    v = _mm_load_pd(b);

    printf_s("Calling _mm_hsub_pd to modify these values.\n");
    w = _mm_hsub_pd ( u , v);

    printf_s("Result: %e %e \n", w.m128d_f64[0], w.m128d_f64[1]);
}

Loading double values 5.000000e-001 3.000000e-001 into XMM register.
Loading double values 5.000000e-003 3.000000e-003 into XMM register.
Calling _mm_hsub_pd to modify these values.
Result: 2.000000e-001 2.000000e-003

See Also

Reference

Compiler Intrinsics