__rdtsc

Microsoft Specific

Generates the rdtsc instruction, which returns the processor time stamp. The processor time stamp records the number of clock cycles since the last reset.

Syntax

unsigned __int64 __rdtsc();  

Return Value

A 64-bit unsigned integer representing a tick count.

Requirements

Intrinsic Architecture
__rdtsc x86, x64

Header file <intrin.h>

Remarks

This routine is available only as an intrinsic.

The interpretation of the TSC value in this generation of hardware differs from that in earlier versions of x64. See hardware manuals for more information.

Example

// rdtsc.cpp  
// processor: x86, x64  
#include <stdio.h>  
#include <intrin.h>  

#pragma intrinsic(__rdtsc)  

int main()  
{  
    unsigned __int64 i;  
    i = __rdtsc();  
    printf_s("%I64d ticks\n", i);  
}  
3363423610155519 ticks  

END Microsoft Specific

See Also

Compiler Intrinsics