/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2004 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This library 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 Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Sam Lantinga slouken@libsdl.org */ #ifdef SAVE_RCSID static char rcsid = "@(#) $Id$"; #endif /* CPU feature detection for SDL */ #include "SDL.h" #include "SDL_cpuinfo.h" #ifdef MACOSX #include /* For AltiVec check */ #endif #define CPU_HAS_RDTSC 0x00000001 #define CPU_HAS_MMX 0x00000002 #define CPU_HAS_3DNOW 0x00000004 #define CPU_HAS_SSE 0x00000008 #define CPU_HAS_ALTIVEC 0x00000010 static __inline__ int CPU_haveCPUID() { int has_CPUID = 0; #if defined(__GNUC__) && defined(i386) __asm__ ( "push %%ecx\n" " pushfl # Get original EFLAGS \n" " popl %%eax \n" " movl %%eax,%%ecx \n" " xorl $0x200000,%%eax # Flip ID bit in EFLAGS \n" " pushl %%eax # Save new EFLAGS value on stack \n" " popfl # Replace current EFLAGS value \n" " pushfl # Get new EFLAGS \n" " popl %%eax # Store new EFLAGS in EAX \n" " xorl %%ecx,%%eax # Can not toggle ID bit, \n" " jz 1f # Processor=80486 \n" " movl $1,%0 # We have CPUID support \n" "1: \n" "pop %%ecx\n" : "=r" (has_CPUID) : : "%eax", "%ecx" ); #elif defined(_MSC_VER) __asm { pushfd ; Get original EFLAGS pop eax mov ecx, eax xor eax, 200000h ; Flip ID bit in EFLAGS push eax ; Save new EFLAGS value on stack popfd ; Replace current EFLAGS value pushfd ; Get new EFLAGS pop eax ; Store new EFLAGS in EAX xor eax, ecx ; Can not toggle ID bit, jz done ; Processor=80486 mov has_CPUID,1 ; We have CPUID support done: } #endif return has_CPUID; } static __inline__ int CPU_getCPUIDFeatures() { int features = 0; #if defined(__GNUC__) && defined(i386) __asm__ ( "push %%ebx\n" "push %%ecx\n" "push %%edx\n" " xorl %%eax,%%eax # Set up for CPUID instruction \n" " cpuid # Get and save vendor ID \n" " cmpl $1,%%eax # Make sure 1 is valid input for CPUID\n" " jl 1f # We dont have the CPUID instruction\n" " xorl %%eax,%%eax \n" " incl %%eax \n" " cpuid # Get family/model/stepping/features\n" " movl %%edx,%0 \n" "1: \n" "pop %%edx\n" "pop %%ecx\n" "pop %%ebx\n" : "=r" (features) : : "%eax", "%ebx", "%ecx", "%edx" ); #elif defined(_MSC_VER) __asm { xor eax, eax ; Set up for CPUID instruction cpuid ; Get and save vendor ID cmp eax, 1 ; Make sure 1 is valid input for CPUID jl done ; We dont have the CPUID instruction xor eax, eax inc eax cpuid ; Get family/model/stepping/features mov features, edx done: } #endif return features; } static __inline__ int CPU_haveRDTSC() { if ( CPU_haveCPUID() ) { return (CPU_getCPUIDFeatures() & 0x00000010); } return 0; } static __inline__ int CPU_haveMMX() { if ( CPU_haveCPUID() ) { return (CPU_getCPUIDFeatures() & 0x00800000); } return 0; } static __inline__ int CPU_have3DNow() { int has_3DNow = 0; if ( !CPU_haveCPUID() ) { return 0; } #if defined(__GNUC__) && defined(i386) __asm__ ( "push %%ebx\n" "push %%ecx\n" "push %%edx\n" " movl $0x80000000,%%eax # Query for extended functions \n" " cpuid # Get extended function limit \n" " cmpl $0x80000001,%%eax \n" " jbe 1f # Nope, we dont have function 800000001h\n" " movl $0x80000001,%%eax # Setup extended function 800000001h\n" " cpuid # and get the information \n" " testl $0x80000000,%%edx # Bit 31 is set if 3DNow! present \n" " jz 1f # Nope, we dont have 3DNow support\n" " movl $1,%0 # Yep, we have 3DNow! support! \n" "1: \n" "pop %%edx\n" "pop %%ecx\n" "pop %%ebx\n" : "=r" (has_3DNow) : : "%eax", "%ebx", "%ecx", "%edx" ); #elif defined(_MSC_VER) __asm { mov eax,80000000h ; Query for extended functions cpuid ; Get extended function limit cmp eax,80000001h jbe done ; Nope, we dont have function 800000001h mov eax,80000001h ; Setup extended function 800000001h cpuid ; and get the information test edx,80000000h ; Bit 31 is set if 3DNow! present jz done ; Nope, we dont have 3DNow support mov has_3DNow,1 ; Yep, we have 3DNow! support! done: } #endif return has_3DNow; } static __inline__ int CPU_haveSSE() { if ( CPU_haveCPUID() ) { return (CPU_getCPUIDFeatures() & 0x02000000); } return 0; } static __inline__ int CPU_haveAltiVec() { #ifdef MACOSX /* TODO: This check works on OS X. It would be nice to detect AltiVec properly on for example Linux/PPC, too. But I don't know how that is done in Linux (or FreeBSD, or whatever other OS you run PPC :-) */ int selectors[2] = { CTL_HW, HW_VECTORUNIT }; int hasVectorUnit = 0; size_t length = sizeof(hasVectorUnit); int error = sysctl(selectors, 2, &hasVectorUnit, &length, NULL, 0); if( 0 == error ) return hasVectorUnit != 0; #endif return 0; } static Uint32 SDL_CPUFeatures = 0xFFFFFFFF; static Uint32 SDL_GetCPUFeatures() { if ( SDL_CPUFeatures == 0xFFFFFFFF ) { SDL_CPUFeatures = 0; if ( CPU_haveRDTSC() ) { SDL_CPUFeatures |= CPU_HAS_RDTSC; } if ( CPU_haveMMX() ) { SDL_CPUFeatures |= CPU_HAS_MMX; } if ( CPU_have3DNow() ) { SDL_CPUFeatures |= CPU_HAS_3DNOW; } if ( CPU_haveSSE() ) { SDL_CPUFeatures |= CPU_HAS_SSE; } if ( CPU_haveAltiVec() ) { SDL_CPUFeatures |= CPU_HAS_ALTIVEC; } } return SDL_CPUFeatures; } SDL_bool SDL_HasRDTSC() { if ( SDL_GetCPUFeatures() & CPU_HAS_RDTSC ) { return SDL_TRUE; } return SDL_FALSE; } SDL_bool SDL_HasMMX() { if ( SDL_GetCPUFeatures() & CPU_HAS_MMX ) { return SDL_TRUE; } return SDL_FALSE; } SDL_bool SDL_Has3DNow() { if ( SDL_GetCPUFeatures() & CPU_HAS_3DNOW ) { return SDL_TRUE; } return SDL_FALSE; } SDL_bool SDL_HasSSE() { if ( SDL_GetCPUFeatures() & CPU_HAS_SSE ) { return SDL_TRUE; } return SDL_FALSE; } SDL_bool SDL_HasAltiVec() { if ( SDL_GetCPUFeatures() & CPU_HAS_ALTIVEC ) { return SDL_TRUE; } return SDL_FALSE; } #ifdef TEST_MAIN #include int main() { printf("RDTSC: %d\n", SDL_HasRDTSC()); printf("MMX: %d\n", SDL_HasMMX()); printf("3DNow: %d\n", SDL_Has3DNow()); printf("SSE: %d\n", SDL_HasSSE()); printf("AltiVec: %d\n", SDL_HasAltiVec()); return 0; } #endif /* TEST_MAIN */