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Microsoft Specific

Generates a store string instruction (rep stosd).

void __stosd( 
   unsigned long* Dest, 
   unsigned long 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 doublewords to write.

Intrinsic Architecture


x86, x64

Header file <intrin.h>

The result is that the doubleword Data is written into a block of Count doublewords at the memory location pointed to by Dest.

This routine is only available as an intrinsic.

// stosd.c
// processor: x86, x64

#include <stdio.h>
#include <memory.h>
#include <intrin.h>

#pragma intrinsic(__stosd)

int main()
    unsigned long val = 99999;
    unsigned long a[10];

    memset(a, 0, sizeof(a));
    __stosd(a+1, val, 2);

printf_s( "%u %u %u %u",
              a[0], a[1], a[2], a[3]); 


0 99999 99999 0

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