/*

    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 */

#ifdef unix /* FIXME: Better setjmp detection? */

#define USE_SETJMP

#include <signal.h>

#include <setjmp.h>

#endif

#include "SDL.h"

#include "SDL_cpuinfo.h"

#ifdef MACOSX

#include <sys/sysctl.h> /* For AltiVec check */

#endif

#define CPU_HAS_RDTSC	0x00000001

#define CPU_HAS_MMX	0x00000002

#define CPU_HAS_MMXEXT	0x00000004

#define CPU_HAS_3DNOW	0x00000010

#define CPU_HAS_3DNOWEXT 0x00000020

#define CPU_HAS_SSE	0x00000040

#define CPU_HAS_SSE2	0x00000080

#define CPU_HAS_ALTIVEC	0x00000100

#ifdef USE_SETJMP

/* This is the brute force way of detecting instruction sets...

   the idea is borrowed from the libmpeg2 library - thanks!

 */

static jmp_buf jmpbuf;

static void illegal_instruction(int sig)

{

	longjmp(jmpbuf, 1);

}

#endif // USE_SETJMP

static __inline__ int CPU_haveCPUID()

{

	int has_CPUID = 0;

#if defined(__GNUC__) && defined(i386)

	__asm__ (

"        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"

	: "=m" (has_CPUID)

	:

	: "%eax", "%ecx"

	);

#elif defined(__GNUC__) && defined(__x86_64__)

/* Technically, if this is being compiled under __x86_64__ then it has 

CPUid by definition.  But it's nice to be able to prove it.  :)      */

	__asm__ (

"        pushfq                      # Get original EFLAGS             \n"

"        popq    %%rax                                                 \n"

"        movq    %%rax,%%rcx                                           \n"

"        xorl    $0x200000,%%eax     # Flip ID bit in EFLAGS           \n"

"        pushq   %%rax               # Save new EFLAGS value on stack  \n"

"        popfq                       # Replace current EFLAGS value    \n"

"        pushfq                      # Get new EFLAGS                  \n"

"        popq    %%rax               # 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"

	: "=m" (has_CPUID)

	:

	: "%rax", "%rcx"

	);

#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) || defined(__x86_64__) )

	__asm__ (

"        movl    %%ebx,%%edi\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"

"        movl    %%edi,%%ebx\n"

	: "=m" (features)

	:

	: "%eax", "%ebx", "%ecx", "%edx", "%edi"

	);

#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_getCPUIDFeaturesExt()

{

	int features = 0;

#if defined(__GNUC__) && (defined(i386) || defined (__x86_64__) )

	__asm__ (

"        movl    %%ebx,%%edi\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"

"        movl    %%edi,%%ebx\n"

	: "=m" (features)

	:

	: "%eax", "%ebx", "%ecx", "%edx", "%edi"

	);

#elif defined(_MSC_VER)

	__asm {

        mov     eax,80000000h       ; Query for extended functions

        cpuid                       ; Get extended function limit

        cmp     eax,80000001h

        jl      done                ; Nope, we dont have function 800000001h

        mov     eax,80000001h       ; Setup extended function 800000001h

        cpuid                       ; and get the information

        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_haveMMXExt()

{

	if ( CPU_haveCPUID() ) {

		return (CPU_getCPUIDFeaturesExt() & 0x00400000);

	}

	return 0;

}

static __inline__ int CPU_have3DNow()

{

	if ( CPU_haveCPUID() ) {

		return (CPU_getCPUIDFeaturesExt() & 0x80000000);

	}

	return 0;

}

static __inline__ int CPU_have3DNowExt()

{

	if ( CPU_haveCPUID() ) {

		return (CPU_getCPUIDFeaturesExt() & 0x40000000);

	}

	return 0;

}

static __inline__ int CPU_haveSSE()

{

	if ( CPU_haveCPUID() ) {

		return (CPU_getCPUIDFeatures() & 0x02000000);

	}

	return 0;

}

static __inline__ int CPU_haveSSE2()

{

	if ( CPU_haveCPUID() ) {

		return (CPU_getCPUIDFeatures() & 0x04000000);

	}

	return 0;

}

static __inline__ int CPU_haveAltiVec()

{

	volatile int altivec = 0;

#ifdef MACOSX

	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 )

		altivec = (hasVectorUnit != 0); 

#elif defined(USE_SETJMP) && defined(GCC_ALTIVEC)

	void (*handler)(int sig);

	handler = signal(SIGILL, illegal_instruction);

	if ( setjmp(jmpbuf) == 0 ) {

		asm volatile ("mtspr 256, %0\n\t"

			      "vand %%v0, %%v0, %%v0"

			      :

			      : "r" (-1));

		altivec = 1;

	}

	signal(SIGILL, handler);

#endif

	return altivec; 

}

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_haveMMXExt() ) {

			SDL_CPUFeatures |= CPU_HAS_MMXEXT;

		}

		if ( CPU_have3DNow() ) {

			SDL_CPUFeatures |= CPU_HAS_3DNOW;

		}

		if ( CPU_have3DNowExt() ) {

			SDL_CPUFeatures |= CPU_HAS_3DNOWEXT;

		}

		if ( CPU_haveSSE() ) {

			SDL_CPUFeatures |= CPU_HAS_SSE;

		}

		if ( CPU_haveSSE2() ) {

			SDL_CPUFeatures |= CPU_HAS_SSE2;

		}

		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_HasMMXExt()

{

	if ( SDL_GetCPUFeatures() & CPU_HAS_MMXEXT ) {

		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_Has3DNowExt()

{

	if ( SDL_GetCPUFeatures() & CPU_HAS_3DNOWEXT ) {

		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_HasSSE2()

{

	if ( SDL_GetCPUFeatures() & CPU_HAS_SSE2 ) {

		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 <stdio.h>

int main()

{

	printf("RDTSC: %d\n", SDL_HasRDTSC());

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

	printf("MMXExt: %d\n", SDL_HasMMXExt());

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

	printf("3DNowExt: %d\n", SDL_Has3DNowExt());

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

	printf("SSE2: %d\n", SDL_HasSSE2());

	printf("AltiVec: %d\n", SDL_HasAltiVec());

	return 0;

}

#endif /* TEST_MAIN */