在为
Windows编写新代码时,我偶然发现了Windows API中的_cpuinfo().因为我主要处理
Linux环境(GCC),所以我希望能够访问cpuInfo.
我尝试过以下方法：
#include <iostream>
int main()
{
int a,b;
for (a = 0; a < 5; a++)
{
__asm ( "mov %1,%%eax; " // a into eax
"cpuid;"
"mov %%eax,%0;" // eax into b
:"=r"(b) // output
:"r"(a) // input
:"%eax","%ebx","%ecx","%edx" // clobbered register
);
std::cout << "The code " << a << " gives " << b << std::endl;
}
return 0;
}
这使用组件,但我不想重新发明轮子.有没有其他方法可以在没有汇编的情况下实现cpuInfo？
编译器错误：
lewis@lewis-desktop:~/Desktop/prog$g++ -Wall cpuInfo.cpp cpuInfo.cpp: In function ‘int main()’: cpuInfo.cpp:10:22: error: expected ‘)’ before ‘;’ token cpuInfo.cpp:10:23: error: expected primary-expression before ‘)’ token cpuInfo.cpp:10:23: error: expected ‘;’ before ‘)’ token cpuInfo.cpp:8:8: warning: unused variable ‘b’ [-Wunused-variable] cpuInfo.cpp:12:8: error: expected ‘}’ at end of input
解决方法
由于您正在使用GCC进行编译,因此您可以包含声明这些函数的cpuid.h：
/* Return highest supported input value for cpuid instruction. ext can be either 0x0 or 0x8000000 to return highest supported value for basic or extended cpuid information. Function returns 0 if cpuid is not supported or whatever cpuid returns in eax register. If sig pointer is non-null,then first four bytes of the signature (as found in ebx register) are returned in location pointed by sig. */ unsigned int __get_cpuid_max (unsigned int __ext,unsigned int *__sig) /* Return cpuid data for requested cpuid level,as found in returned eax,ebx,ecx and edx registers. The function checks if cpuid is supported and returns 1 for valid cpuid information or 0 for unsupported cpuid level. All pointers are required to be non-null. */ int __get_cpuid (unsigned int __level,unsigned int *__eax,unsigned int *__ebx,unsigned int *__ecx,unsigned int *__edx)
您不需要也不应该重新实现此功能.
