/*

SDL - Simple DirectMedia Layer

Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 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"

#define CPU_HAS_RDTSC 0x00000001

#define CPU_HAS_MMX 0x00000002

#define CPU_HAS_3DNOW 0x00000004

#define CPU_HAS_SSE 0x00000008

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 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;

}

}

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;

}

#ifdef TEST_MAIN

#include <stdio.h>

int main()

{

printf("MMX: %d\n", SDL_HasMMX());

printf("3DNow: %d\n", SDL_Has3DNow());

printf("SSE: %d\n", SDL_HasSSE());

}

#endif /* TEST_MAIN */