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Documentation                       Search   cpu_info.cpp Go to the documentation of this file. /* Copyright, 2000, 2001 Nevrax Ltd. * * This file is part of NEVRAX NEL. * NEVRAX NEL is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * NEVRAX NEL is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * You should have received a copy of the GNU General Public License * along with NEVRAX NEL; see the file COPYING. If not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, * MA 02111-1307, USA. */ #include "stdmisc.h" #include "nel/misc/cpu_info.h" namespace NLMISC { static bool DetectMMX(void) { #ifdef NL_OS_WINDOWS if (!CCpuInfo___::hasCPUID()) return false; // cpuid not supported ... uint32 result = 0; __asm { mov eax,1 cpuid test edx,0x800000 // bit 23 = MMX instruction set je noMMX mov result, 1 noMMX: } return result == 1; // printf("mmx detected\n"); #else return false; #endif } static bool DetectSSE(void) { #ifdef NL_OS_WINDOWS if (!CCpuInfo___::hasCPUID()) return false; // cpuid not supported ... uint32 result = 0; __asm { mov eax, 1 // request for feature flags cpuid test EDX, 002000000h // bit 25 in feature flags equal to 1 je noSSE mov result, 1 // sse detected noSSE: } if (result) { // check OS support for SSE try { __asm { xorps xmm0, xmm0 // Streaming SIMD Extension } } catch(...) { return false; } // printf("sse detected\n"); return true; } else { return false; } #else return false; #endif } bool HasMMX = DetectMMX(); bool HasSSE = DetectSSE(); bool CCpuInfo___::hasCPUID(void) { #ifdef NL_OS_WINDOWS uint32 result; __asm { pushad pushfd // If ID bit of EFLAGS can change, then cpuid is available pushfd pop eax // Get EFLAG mov ecx,eax xor eax,0x200000 // Flip ID bit push eax popfd // Write EFLAGS pushfd pop eax // read back EFLAG xor eax,ecx je noCpuid // no flip -> no CPUID instr. popfd // restore state popad mov result, 1 jmp CPUIDPresent noCpuid: popfd // restore state popad mov result, 0 CPUIDPresent: } return result == 1; #else return false; #endif } bool CCpuInfo___::hasMMX(void) { return HasMMX; } bool CCpuInfo___::hasSSE(void) { return HasSSE; } } // NLMISC