i5-2500k上的cpuid指令:未设置MMX,SSE,SSE2位

Question

这是预期的吗？我希望我的Sandy Bridge CPU报告它可以处理MMX,SSE和SSE2指令.这些位是否未设置,因为这些"旧"指令集已被某些较新的指令集"取代"？

我在这里使用此代码将CPU检测放入我的代码中.

#include "CPUID.h"
int main(int argc, char *argv[]) {
    CPUID cpuid;
    cpuid.load(0);
    printf("CPU: %.4s%.4s%.4s", 
        (const char*)&cpuid.EBX(),
        (const char*)&cpuid.EDX(),
        (const char*)&cpuid.ECX()
    );
    char brand[0x30];
    cpuid.load(0x80000002); memcpy(brand,&cpuid.EAX(),16);
    cpuid.load(0x80000003); memcpy(brand+16,&cpuid.EAX(),16);
    cpuid.load(0x80000004); memcpy(brand+32,&cpuid.EAX(),16);
    printf("%.48s\n",brand);
    cpuid.load(1);
    // tests bit 23 of ECX for popcnt instruction support
    printf("MMX - %s\n", cpuid.EAX() & (1 << 23) ? "yes" : "no");
    printf("SSE - %s\n", cpuid.EAX() & (1 << 25) ? "yes" : "no"); 
    printf("SSE2 - %s\n", cpuid.EAX() & (1 << 26) ? "yes" : "no"); 
    printf("SSE3 - %s\n", cpuid.ECX() & (1 << 0) ? "yes" : "no"); 
    printf("SSSE3 - %s\n", cpuid.ECX() & (1 << 9) ? "yes" : "no"); 
    printf("SSE4.1 - %s\n", cpuid.ECX() & (1 << 19) ? "yes" : "no"); 
    printf("SSE4.2 - %s\n", cpuid.ECX() & (1 << 20) ? "yes" : "no"); 
    printf("AES - %s\n", cpuid.ECX() & (1 << 25) ? "yes" : "no"); 
    printf("AVX - %s\n", cpuid.ECX() & (1 << 28) ? "yes" : "no"); 
    printf("HT - %s\n", cpuid.EAX() & (1 << 28) ? "yes" : "no"); 
    printf("IA64 (emulating x86) - %s\n", cpuid.EAX() & (1 << 30) ? "yes" : "no"); 
    printf("Hypervisor? - %s\n", cpuid.ECX() & (1 << 31) ? "yes" : "no"); 
    printf("popcnt - %s\n", cpuid.ECX() & (1 << 23) ? "yes" : "no");
    return 0;
}

输出:

CPU: GenuineIntel       Intel(R) Core(TM) i5-2500K CPU @ 3.30GHz
MMX - no
SSE - no
SSE2 - no
SSE3 - yes
SSSE3 - yes
SSE4.1 - yes
SSE4.2 - yes
AES - yes
AVX - yes
HT - no
IA64 (emulating x86) - no
Hypervisor? - no
popcnt - yes

Answer 1

愚蠢的错误.我假设表中的第一行是针对EAX的,但它适用于EDX.

产生了正确的结果.好吧,这个芯片不支持HT,但可能总是设置.

更新:结果"HT"表示包装上的> 1个逻辑线程(该芯片有4个).

CPU: GenuineIntel       Intel(R) Core(TM) i5-2500K CPU @ 3.30GHz
MMX - yes
SSE - yes
SSE2 - yes
SSE3 - yes
SSSE3 - yes
SSE4.1 - yes
SSE4.2 - yes
AES - yes
AVX - yes
HT - yes
IA64 (emulating x86) - no
Hypervisor? - no
popcnt - yes