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_mm_sign_epi32

Microsoft Specific

Emits the Supplemental Streaming SIMD Extensions 3 (SSSE3) instruction psignd. This instruction negates or clears 32-bit signed integers of a 128-bit parameter.

__m128i _mm_sign_epi32( 
   __m128i a,
   __m128i b
);

Parameters

  • [in] a
    A 128-bit parameter that contains four 32-bit signed integers.

  • [in] b
    A 128-bit parameter that contains four 32-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

Intrinsic

Architecture

_mm_sign_epi32

x86, x64

Header file <tmmintrin.h>

Remarks

r0-r3, a0-a3, and b0-b3 are the sequentially ordered 32-bit components of return value r and parameters a and b. r0, a0, and b0 are the least significant 32 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 ()
{
    __m128i a, b;

    a.m128i_i32[0] = 32000;
    a.m128i_i32[1] = -6;
    a.m128i_i32[2] = 3141259;
    a.m128i_i32[3] = -42;

    b.m128i_i32[0] = 1;
    b.m128i_i32[1] = 0;
    b.m128i_i32[2] = -1;
    b.m128i_i32[3] = -75000;

    __m128i res = _mm_sign_epi32(a, b);

    printf_s("       a\t       b\t     res\n%8d\t%8d\t%8d\n%8d\t%8d\t%8d\n",
                a.m128i_i32[0], b.m128i_i32[0], res.m128i_i32[0],
                a.m128i_i32[1], b.m128i_i32[1], res.m128i_i32[1]);
    printf_s("%8d\t%8d\t%8d\n%8d\t%8d\t%8d\n",
                a.m128i_i32[2], b.m128i_i32[2], res.m128i_i32[2],
                a.m128i_i32[3], b.m128i_i32[3], res.m128i_i32[3]);

    return 0;
}
       a               b             res
   32000               1           32000
      -6               0               0
 3141259              -1        -3141259
     -42          -75000              42

See Also

Concepts

Compiler Intrinsics