Microsoft Specific

Writes 64-bit data to a memory location without polluting the caches.

void _mm_stream_sd(  
   double * Dest,  
   __m128d Source  


[out] Dest
A pointer to the location where the source data will be written.

[in] Source
A 128-bit value containing the double value to be written in its bottom 64 bits..



Header file <intrin.h>

This intrinsic generates the movntsd instruction. To determine hardware support for this instruction, call the __cpuid intrinsic with InfoType=0x80000001 and check bit 6 of CPUInfo[2] (ECX). This bit is 1 if the hardware supports this instruction, and 0 otherwise.

If you run code that uses the _mm_stream_sd intrinsic on hardware that does not support the movntsd instruction, the results are unpredictable.

// Compile this sample with: /EHsc  
#include <iostream>  
#include <intrin.h>  
using namespace std;  
int main()  
    __m128d vals;  
    double d[2];  
    d[0] = -1.;  
    d[1] = -2.;  
    vals.m128d_f64[0] = 0.;  
    vals.m128d_f64[1] = 1.;  
    _mm_stream_sd(&d[1], vals);  
    cout << "d[0] = " << d[0] << ", d[1] = " << d[1] << endl;  

d[0] = -1, d[1] = 1  

Copyright 2007 by Advanced Micro Devices, Inc. All rights reserved. Reproduced with permission from Advanced Micro Devices, Inc.

Streaming SIMD Extensions that Support the Cache
Compiler Intrinsics