_mm_haddd_epi8

[Note: This document describes a pre-release version of Visual Studio 2010 SP1 and may be revised in any later version.]

Visual Studio 2010 SP1 is required.

Microsoft Specific

Generates the XOP instruction vphaddbd to perform an integer horizontal add of its source.

__m128i _mm_haddd_epi8 (
   __m128i src
);

Parameters

• [in] src
  A 128-bit parameter that contains sixteen 8-bit signed integers.

Return value

A 128-bit result r that contains four 32-bit signed integers.

r[i] := src[4*i] + src[4*i+1] + src[4*i+2] + src[4*i+3];

Requirements

Header file <intrin.h>

Remarks

Each of the four groups of four consecutive 8-bit signed integer values in src is added to produce a 32-bit signed integer result that is stored as the corresponding value in the destination. No overflow is possible in this instruction.

The vphaddbd instruction is part of the XOP family of instructions. Before you use this intrinsic, you must ensure that the processor supports this instruction. To determine hardware support for this instruction, call the __cpuid intrinsic with InfoType = 0x80000001 and check bit 11 of CPUInfo[2] (ECX). This bit is 1 when the instruction is supported, and 0 otherwise.

Example

#include <stdio.h>
#include <intrin.h>
int main()
{
    __m128i a, d;
    int i;
    for (i = 0; i < 4; i++) {
        a.m128i_i8[i] = -128;
        a.m128i_i8[i+4] = i-128;
        a.m128i_i8[i+8] = 10*i;
        a.m128i_i8[i+12] = 127;
    }
    d = _mm_haddd_epi8(a);
    for (i = 0; i < 4; i++) printf_s(" %d", d.m128i_i32[i]);
    printf_s("\n");
}

-512 -506 60 508

See Also

Reference

_mm_haddw_epi8

_mm_haddq_epi8

_mm_haddd_epi16

_mm_haddd_epu8

__cpuid, __cpuidex

XOP Intrinsics Added for Visual Studio 2010 SP1

Change History