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_mm_cvtepu8_epi64

Microsoft Specific

Emits the Streaming SIMD Extensions 4 (SSE4) instruction pmovzxbq. This instruction performs a conversion of unsigned integers from 8-bit to 64-bit.

__m128i _mm_cvtepu8_epi64( 
   __m128i a
);

Parameters

  • [in] a
    A 128-bit parameter that contains two unsigned 8-bit integers in the lower 16 bits.

Return value

A 128-bit parameter that contains two 64-bit integers. These integers are zero-extended representations of the 8-bit integers that are supplied by a.

The result can be defined with the following equations:

r0 := a0
r1 := 0
r2 := 0
r3 := 0
r4 := 0
r5 := 0
r6 := 0
r7 := 0

r8 := a1
r9 := 0
r10 := 0
r11 := 0
r12 := 0
r13 := 0
r14 := 0
r15 := 0

Requirements

Intrinsic

Architecture

_mm_cvtepu8_epi64

x86, x64

Header file <smmintrin.h>

Remarks

r0-r15 and a0-a15 are the sequentially ordered 8-bit components of return value r and parameter a, respectively. r0 and a0 are the least significant 8 bits.

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

Example

#include <stdio.h>
#include <smmintrin.h>

int main ()
{
    __m128i a;

    a.m128i_u8[0] = 0;
    a.m128i_u8[1] = 254;

    __m128i res = _mm_cvtepu8_epi64(a);

    printf_s("Original lowest 8 bit integers:\n%u,\t%u\n\n",
        a.m128i_u8[1], a.m128i_u8[0]);

    printf_s("Resulting 64 bit integers:\n%I64i,\t%I64i\n",
        res.m128i_i64[1], res.m128i_i64[0]);

    return 0;
}

Original lowest 8 bit integers:
254,    0

Resulting 64 bit integers:
254,    0

See Also

Concepts

Compiler Intrinsics