nevrax.org : docs

00001 
+00007 /* Copyright, 2000, 2001 Nevrax Ltd.
+00008  *
+00009  * This file is part of NEVRAX NEL.
+00010  * NEVRAX NEL is free software; you can redistribute it and/or modify
+00011  * it under the terms of the GNU General Public License as published by
+00012  * the Free Software Foundation; either version 2, or (at your option)
+00013  * any later version.
+00014 
+00015  * NEVRAX NEL is distributed in the hope that it will be useful, but
+00016  * WITHOUT ANY WARRANTY; without even the implied warranty of
+00017  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+00018  * General Public License for more details.
+00019 
+00020  * You should have received a copy of the GNU General Public License
+00021  * along with NEVRAX NEL; see the file COPYING. If not, write to the
+00022  * Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+00023  * MA 02111-1307, USA.
+00024  */
+00025 
+00026 #include "stdmisc.h"
+00027 
+00028 #include "nel/misc/cpu_info.h"
+00029 
+00030 
+00031 namespace NLMISC 
+00032 {
+00033 
+00034 static bool DetectMMX(void)
+00035 {               
+00036         #ifdef NL_OS_WINDOWS            
+00037                 if (!CCpuInfo___::hasCPUID()) return false; // cpuid not supported ...
+00038 
+00039                 uint32 result = 0;
+00040                 __asm
+00041                 {
+00042                          mov  eax,1
+00043                          cpuid
+00044                          test edx,0x800000  // bit 23 = MMX instruction set
+00045                          je   noMMX
+00046                          mov result, 1  
+00047                         noMMX:
+00048                 }
+00049 
+00050                 return result == 1;
+00051  
+00052                 // printf("mmx detected\n");
+00053 
+00054         #else
+00055                 return false;
+00056         #endif
+00057 }
+00058 
+00059 
+00060 static bool DetectSSE(void)
+00061 {       
+00062         #ifdef NL_OS_WINDOWS
+00063                 if (!CCpuInfo___::hasCPUID()) return false; // cpuid not supported ...
+00064 
+00065                 uint32 result = 0;
+00066                 __asm
+00067                 {                       
+00068                         mov eax, 1   // request for feature flags
+00069                         cpuid                                                   
+00070                         test EDX, 002000000h   // bit 25 in feature flags equal to 1
+00071                         je noSSE
+00072                         mov result, 1  // sse detected
+00073                 noSSE:
+00074                 }
+00075 
+00076 
+00077                 if (result)
+00078                 {
+00079                         // check OS support for SSE
+00080                         try 
+00081                         {
+00082                                 __asm
+00083                                 {
+00084                                         xorps xmm0, xmm0  // Streaming SIMD Extension
+00085                                 }
+00086                         }
+00087                         catch(...)
+00088                         {
+00089                                 return false;
+00090                         }
+00091                 
+00092                         // printf("sse detected\n");
+00093 
+00094                         return true;
+00095                 }
+00096                 else
+00097                 {
+00098                         return false;
+00099                 }
+00100         #else
+00101                 return false;
+00102         #endif
+00103 }
+00104 
+00105 bool HasMMX = DetectMMX();
+00106 bool HasSSE = DetectSSE();
+00107 
+00108 bool CCpuInfo___::hasCPUID(void)
+00109 {
+00110         #ifdef NL_OS_WINDOWS
+00111                  uint32 result;
+00112                  __asm
+00113                  {
+00114                          pushad
+00115                          pushfd                                         
+00116                          //      If ID bit of EFLAGS can change, then cpuid is available
+00117                          pushfd
+00118                          pop  eax                                       // Get EFLAG
+00119                          mov  ecx,eax
+00120                          xor  eax,0x200000                      // Flip ID bit
+00121                          push eax
+00122                          popfd                                          // Write EFLAGS
+00123                          pushfd      
+00124                          pop  eax                                       // read back EFLAG
+00125                          xor  eax,ecx                           
+00126                          je   noCpuid                           // no flip -> no CPUID instr.
+00127                          
+00128                          popfd                                          // restore state
+00129                          popad
+00130                          mov  result, 1
+00131                          jmp  CPUIDPresent
+00132                 
+00133                         noCpuid:
+00134                          popfd                                      // restore state
+00135                          popad
+00136                          mov result, 0
+00137                         CPUIDPresent:    
+00138                  }
+00139                  return result == 1;
+00140         #else
+00141                  return false;
+00142         #endif
+00143 }
+00144 bool CCpuInfo___::hasMMX(void) { return HasMMX; }
+00145 bool CCpuInfo___::hasSSE(void) { return HasSSE; }
+00146 
+00147 } // NLMISC
+
cpu_info.cpp
