#include #include unsigned int a,b,c,d; // EAX, EBX, ECX, EDX unsigned int maxFn = 0; // Using this as reference: https://en.m.wikipedia.org/wiki/CPUID // 2018-04-12 bugfix: model/family masks (Python showed me difference). rdrnd changed to rdrand (I think this was intended) void cpuVendorID(){ char str[13]="-={[(<>)]}=-"; // 12 spaces + null __get_cpuid(0x0, &maxFn, (unsigned int*)&str[0], (unsigned int*)&str[8], (unsigned int *)&str[4]); printf("[%d] Highest BASIC function supported\n[\"%s\"] CPU string\n", maxFn, str); } void cpuSignature(){ a=0; b=0; c=0; d=0; /******** EAX processing ********/ /* 0000 00000000 ..000000 00001111 stepping * 0000 00000000 ..000000 11110000 model * 0000 00000000 ..001111 00000000 family * 0000 00000000 ..110000 00000000 processor type * 0000 00001111 ..000000 00000000 extended model * 1111 11110000 ..000000 00000000 extended family */ unsigned int maskS = 8+4+2+1; // stepping unsigned int maskM = 128+64+32+16; // model unsigned int maskF = 15 << 8; // family unsigned int maskP = 3 << 12; // processor type unsigned int maskEM = (16-1)<<16; // ext.model unsigned int maskEF = (256-1)<<20; // ext.family __get_cpuid(0x1, &a, &b, &c, &d); // EAX: using masks above // EBX, ECX, EDX : extended feature information int stepping = a & maskS; int model = (a & maskM) >> 4; int family = (a & maskF) >> 8; int type = (a & maskP) >> 12; switch(family) { case 15: family += (a & maskEF) >> 20; // only 15 adds to family case 6: // 15 and 6 add to model model += (a & maskEM) >> 12; // 4-bit left shift break; default: break; } printf("[%d] Stepping [%d] Model [%d] Family [%d] Type\n", stepping, model, family, type); /******** EBX processing ********/ unsigned int brandIndex = (256-1); // bits 7-0 unsigned int clFlushSz = (256-1) << 8; // bits 15-8 unsigned int maxIDs = (256-1) << 16; // bits 23-16 unsigned int apicID = (256-1) << 24; // bits 31-24 unsigned int isCLFLUSHSet = d&(1<<18); // bit 19 unsigned int isHyperTSet = d&(1<<27); // bit 28 printf("[%d] brand index [%d] CLFLUSH line size (%svalid) [%d] logical processors (%svalid) [%d] current logical CPU (running this code; 0-based)\n", b&brandIndex, (b&clFlushSz)>>8, (isCLFLUSHSet?"in":"is "), // only valid if CLFLUSH feature flag set (b&maxIDs)>>16, (isHyperTSet?"in":"is "), // only valid if hyperthreading feature flag set (b&apicID)>>24 ); /********* ECX + EDX processing ********/ const char* cx[32]; cx[0]="sse3"; cx[1]="pclmulqdq"; cx[2]="dtes64"; cx[3]="monitor"; cx[4]="ds-cpl"; cx[5]="vmx"; cx[6]="smx"; cx[7]="est"; cx[8]="tm2"; cx[9]="ssse3"; cx[10]="cnxt-id"; cx[11]="sdbg"; cx[12]="*fma"; cx[13]="*cx16"; cx[14]="*xtpr"; cx[15]="*pdcm"; cx[16]="reserved(bit 17)"; cx[17]="pcid"; cx[18]="dca"; cx[19]="sse4.1"; cx[20]="sse4.2"; cx[21]="x2apic"; cx[22]="movbe"; cx[23]="popcnt"; cx[24]="tsc-deadline"; cx[25]="aes"; cx[26]="xsave"; cx[27]="osxsave"; cx[28]="*avx"; cx[29]="*f16c"; cx[30]="*rdrand"; cx[31]="*hypervisor"; const char* dx[32]; dx[0]="fpu"; dx[1]="vme"; dx[2]="de"; dx[3]="pse"; dx[4]="tsc"; dx[5]="msr"; dx[6]="pae"; dx[7]="mce"; dx[8]="cx8"; dx[9]="apic"; dx[10]="reserved(bit 11)"; dx[11]="sep"; dx[12]="*mtrr"; dx[13]="*pge"; dx[14]="*mca"; dx[15]="*cmov"; dx[16]="pat"; dx[17]="pse-36"; dx[18]="psn"; dx[19]="clfsh"; dx[20]="reserved(bit 21)"; dx[21]="ds"; dx[22]="acpi"; dx[23]="mmx"; dx[24]="fxsr"; dx[25]="sse"; dx[26]="sse2"; dx[27]="ss"; dx[28]="*htt"; dx[29]="*tm"; dx[30]="*ia64"; dx[31]="*pbe"; printf("--> CPU flags (* listed as reserved):\n"); for(int ci=0; ci<32; ci++) if(c & (1<> 16) & 0xffff, c & 0xff, (c>>12) & 0xf); } //if (!__get_cpuid (0x1, &a, &b, &c, &d)) // EAX, EBX, ECX, EDX // fprintf (stderr, "Warning: CPUID request unsupported!\n"); int main() { printf("--> Some basic functions:\n"); cpuVendorID(); // function 0 cpuSignature(); // function 1 printf("\n--> Some extended functions:\n"); highestExtendedFn(); // function 0x80000000 (0 + MSB) getProcesserBrandString(); // extended fn 2+3+4 getL1CacheSize(); // extended function 5 getL2CacheSize(); // extended function 6 printf("\n--> Skipping...(this is just a demo; see link)\n"); printf("** Basic 2: Cache and TLB Descriptor info\n** Basic 3: Processor Serial Number\n** Basic 7: extended features\n"); printf("** Extended 80000001h: Extended Processor Info and Feature Bits...\n** other functions not documented at link."); // ext fn 1 return 0; }

CPU-ID : let's query CPU info [bugfix: model/family]