Mercurial > sdl-ios-xcode
diff src/cpuinfo/SDL_cpuinfo.c @ 2915:deb377097225
Fixed CPU feature detection on x86_64 platform
(registers were being corrupted, causing crashes)
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Wed, 24 Dec 2008 13:13:38 +0000 |
| parents | 99210400e8b9 |
| children | 0b160c970b7e |
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--- a/src/cpuinfo/SDL_cpuinfo.c Wed Dec 24 13:04:18 2008 +0000 +++ b/src/cpuinfo/SDL_cpuinfo.c Wed Dec 24 13:13:38 2008 +0000 @@ -152,7 +152,7 @@ { int features = 0; /* *INDENT-OFF* */ -#if defined(__GNUC__) && ( defined(i386) || defined(__x86_64__) ) +#if defined(__GNUC__) && defined(i386) __asm__ ( " movl %%ebx,%%edi\n" " xorl %%eax,%%eax # Set up for CPUID instruction \n" @@ -169,6 +169,23 @@ : : "%eax", "%ecx", "%edx", "%edi" ); +#elif defined(__GNUC__) && defined(__x86_64__) + __asm__ ( +" movq %%rbx,%%rdi\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" +" movq %%rdi,%%rbx\n" + : "=m" (features) + : + : "%rax", "%rcx", "%rdx", "%rdi" + ); #elif (defined(_MSC_VER) && defined(_M_IX86)) || defined(__WATCOMC__) __asm { xor eax, eax ; Set up for CPUID instruction @@ -208,7 +225,7 @@ { int features = 0; /* *INDENT-OFF* */ -#if defined(__GNUC__) && (defined(i386) || defined (__x86_64__) ) +#if defined(__GNUC__) && defined(i386) __asm__ ( " movl %%ebx,%%edi\n" " movl $0x80000000,%%eax # Query for extended functions \n" @@ -224,6 +241,22 @@ : : "%eax", "%ecx", "%edx", "%edi" ); +#elif defined(__GNUC__) && defined (__x86_64__) + __asm__ ( +" movq %%rbx,%%rdi\n" +" movl $0x80000000,%%eax # Query for extended functions \n" +" cpuid # Get extended function limit \n" +" cmpl $0x80000001,%%eax \n" +" jl 1f # Nope, we dont have function 800000001h\n" +" movl $0x80000001,%%eax # Setup extended function 800000001h\n" +" cpuid # and get the information \n" +" movl %%edx,%0 \n" +"1: \n" +" movq %%rdi,%%rbx\n" + : "=m" (features) + : + : "%rax", "%rcx", "%rdx", "%rdi" + ); #elif (defined(_MSC_VER) && defined(_M_IX86)) || defined(__WATCOMC__) __asm { mov eax,80000000h ; Query for extended functions