readtimestampcounter函数在msdn上没找到,是不是windows api ? 作用是什么?
在winnt.h头文件中有宏定义#define ReadTimeStampCounter() __rdtsc() _rdtsc函数什么功能?
在msdn上有:
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.
好像是生成了一个rdtsc指令 对指令不太懂(是汇编语言中的吗?)