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Microsoft Specific

Generates a store string instruction (rep stosw).

void __stosw( 
   unsigned short* Dest, 
   unsigned short Data, 
   size_t Count 


[out] Dest

The destination of the operation.

[in] Data

The data to store.

[in] Count

The length of the block of words to write.

Intrinsic Architecture


x86, x64

Header file <intrin.h>

The result is that the word Data is written into a block of Count words in the Dest string.

This routine is only available as an intrinsic.

// stosw.c
// processor: x86, x64
#include <stdio.h>
#include <intrin.h>

#pragma intrinsic(__stosw)

int main()
    unsigned short val = 128;
    unsigned short a[100];
    memset(a, 0, sizeof(a));
    __stosw(a+10, val, 2);
    printf_s("%u %u %u %u", a[9], a[10], a[11], a[12]);   


0 128 128 0

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