_mm_sign_pi16

Microsoft Specific

Emits the Supplemental Streaming SIMD Extensions 3 (SSSE3) instruction psignw. This instruction negates or clears 16-bit signed integers of a 64-bit parameter.

__m64 _mm_sign_pi16( 
   __m64 a,
   __m64 b
);

Parameters

• [in] a
  A 64-bit parameter that contains four 16-bit signed integers.

• [in] b
  A 64-bit parameter that contains four 16-bit signed integers.

Return value

The return value can be expressed with the following equations.

r0 := (b0 < 0) ? -a0 : ((b0 == 0) ? 0 : a0)

r1 := (b1 < 0) ? -a1 : ((b1 == 0) ? 0 : a1)

r2 := (b2 < 0) ? -a2 : ((b2 == 0) ? 0 : a2)

r3 := (b3 < 0) ? -a3 : ((b3 == 0) ? 0 : a3)

Requirements

Header file <tmmintrin.h>

Remarks

r0-r3, a0-a3, and b0-b3 are the sequentially ordered 16-bit components of return value r and parameters a and b. r0, a0, and b0 are the least significant 16 bits.

Before you use this intrinsic, software must ensure that the underlying processor supports the instruction.

Example

#include <stdio.h>
#include <tmmintrin.h>

int main ()
{
    __m64 a, b;

    a.m64_i16[0] = 32000;
    a.m64_i16[1] = -6000;
    a.m64_i16[2] = 5319;
    a.m64_i16[3] = -1753;

    b.m64_i16[0] = 1;
    b.m64_i16[1] = 0;
    b.m64_i16[2] = -1;
    b.m64_i16[3] = -4096;

    __m64 res = _mm_sign_pi16(a, b);

    printf_s("     a\t     b\t   res\n%6d\t%6d\t%6d\n%6d\t%6d\t%6d\n",
                a.m64_i16[0], b.m64_i16[0], res.m64_i16[0],
                a.m64_i16[1], b.m64_i16[1], res.m64_i16[1]);
    printf_s("%6d\t%6d\t%6d\n%6d\t%6d\t%6d\n",
                a.m64_i16[2], b.m64_i16[2], res.m64_i16[2],
                a.m64_i16[3], b.m64_i16[3], res.m64_i16[3]);

    _mm_empty();

    return 0;
}

     a       b     res
 32000       1   32000
 -6000       0       0
  5319      -1   -5319
 -1753   -4096    1753

See Also

Concepts

Compiler Intrinsics