__stosq

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The latest version of this topic can be found at __stosq.

Microsoft Specific**

Generates a store string instruction (rep stosq).

void __stosb(   
   unsigned __int64* Dest,   
   unsigned __int64 Data,   
   size_t Count   
);  

Parameters

[out] Dest
The destination of the operation.

[in] Data
The data to store.

[in] Count
The length of the block of quadwords to write.

Header file <intrin.h>

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

This routine is only available as an intrinsic.

// stosq.c  
// processor: x64  
#include <stdio.h>  
#include <intrin.h>  
  
#pragma intrinsic(__stosq)  
  
int main()  
{  
   unsigned __int64 val = 0xFFFFFFFFFFFFI64;  
   unsigned __int64 a[10];  
   memset(a, 0, sizeof(a));  
   __stosq(a+1, val, 2);  
   printf("%I64x %I64x %I64x %I64x", a[0], a[1], a[2], a[3]);   
}  

0 ffffffffffff ffffffffffff 0  

END Microsoft Specific

Compiler Intrinsics