Microsoft Specific

Emits the Streaming SIMD Extensions 4 (SSE4) instruction pmovzxwq. This instruction performs a conversion of unsigned integers from 16-bit to 64-bit.

__m128i _mm_cvtepu16_epi64( 
   __m128i a

[in] a

A 128-bit parameter that contains two unsigned 16-bit integers in the lower 32 bits.

A 128-bit parameter that contains two 64-bit integers. These integers are zero-extended representations of the 16-bit integers that are supplied by a.




x86, x64

Header file <smmintrin.h>

The result is defined as follows:

r0 := a0
r1 := 0
r2 := 0
r3 := 0

r4 := a1
r5 := 0
r6 := 0
r7 := 0

r0-r7 and a0-a7 are the sequentially ordered 16-bit components of return value r and parameter a, respectively. r0 and a0 are the least significant 16 bits.

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

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

int main ()
    __m128i a;

    a.m128i_u16[0] = 0;
    a.m128i_u16[1] = 65535;

    __m128i res = _mm_cvtepu16_epi64(a);

    printf_s("Original lowest 16 bit integers:\n%u,\t%u\n\n",
        a.m128i_u16[1], a.m128i_u16[0]);

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

    return 0;
Original lowest 16 bit integers: 65535, 0 Resulting 64 bit integers: 65535, 0

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