/*****************************************************************************
 * cpu.c: h264 encoder library
 *****************************************************************************
 * Copyright (C) 2003 Laurent Aimar
 * $Id: cpu.c,v 1.1 2004/06/03 19:27:06 fenrir Exp $
 *
 * Authors: Laurent Aimar <fenrir@via.ecp.fr>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
 *****************************************************************************/

#if defined(HAVE_PTHREAD) && defined(SYS_LINUX)
#define _GNU_SOURCE
#include <sched.h>
#endif
#ifdef SYS_BEOS
#include <kernel/OS.h>
#endif
#ifdef SYS_MACOSX
#include <sys/types.h>
#include <sys/sysctl.h>
#endif

#include <string.h>

#include "common.h"

#if ( defined(ARCH_X86) || defined(ARCH_X86_64) ) && defined(HAVE_MMX)
extern int  x264_cpu_cpuid_test( void );
extern uint32_t  x264_cpu_cpuid( uint32_t op, uint32_t *eax, uint32_t *ebx, uint32_t *ecx, uint32_t *edx );
extern void x264_emms( void );

uint32_t x264_cpu_detect( void )
{
    uint32_t cpu = 0;

    uint32_t eax, ebx, ecx, edx;
    int      b_amd;

    if( !x264_cpu_cpuid_test() )
    {
        /* No cpuid */
        return 0;
    }

    x264_cpu_cpuid( 0, &eax, &ebx, &ecx, &edx);
    if( eax == 0 )
    {
        return 0;
    }
    b_amd   = (ebx == 0x68747541) && (ecx == 0x444d4163) && (edx == 0x69746e65);

    x264_cpu_cpuid( 1, &eax, &ebx, &ecx, &edx );
    if( (edx&0x00800000) == 0 )
    {
        /* No MMX */
        return 0;
    }
    cpu = X264_CPU_MMX;
    if( (edx&0x02000000) )
    {
        /* SSE - identical to AMD MMX extensions */
        cpu |= X264_CPU_MMXEXT|X264_CPU_SSE;
    }
    if( (edx&0x04000000) )
    {
        /* Is it OK ? */
        cpu |= X264_CPU_SSE2;
    }
#ifdef HAVE_SSE3
    if( (ecx&0x00000001) )
    {
        cpu |= X264_CPU_SSE3;
    }
    if( (ecx&0x00000200) )
    {
        cpu |= X264_CPU_SSSE3;
    }
#endif

    x264_cpu_cpuid( 0x80000000, &eax, &ebx, &ecx, &edx );
    if( eax < 0x80000001 )
    {
        /* no extended capabilities */
        return cpu;
    }

    x264_cpu_cpuid( 0x80000001, &eax, &ebx, &ecx, &edx );
    if( edx&0x80000000 )
    {
        cpu |= X264_CPU_3DNOW;
    }
    if( b_amd && (edx&0x00400000) )
    {
        /* AMD MMX extensions */
        cpu |= X264_CPU_MMXEXT;
    }

    return cpu;
}

void     x264_cpu_restore( uint32_t cpu )
{
    if( cpu&(X264_CPU_MMX|X264_CPU_MMXEXT|X264_CPU_3DNOW|X264_CPU_3DNOWEXT) )
    {
        x264_emms();
    }
}

#elif defined( ARCH_PPC )

#ifdef SYS_MACOSX
#include <sys/sysctl.h>
uint32_t x264_cpu_detect( void )
{
    /* Thank you VLC */
    uint32_t cpu = 0;
    int      selectors[2] = { CTL_HW, HW_VECTORUNIT };
    int      has_altivec = 0;
    size_t   length = sizeof( has_altivec );
    int      error = sysctl( selectors, 2, &has_altivec, &length, NULL, 0 );

    if( error == 0 && has_altivec != 0 )
    {
        cpu |= X264_CPU_ALTIVEC;
    }

    return cpu;
}

#elif defined( SYS_LINUX )
#include <signal.h>
#include <setjmp.h>
static sigjmp_buf jmpbuf;
static volatile sig_atomic_t canjump = 0;

static void sigill_handler( int sig )
{
    if( !canjump )
    {
        signal( sig, SIG_DFL );
        raise( sig );
    }

    canjump = 0;
    siglongjmp( jmpbuf, 1 );
}

uint32_t x264_cpu_detect( void )
{
    static void (* oldsig)( int );

    oldsig = signal( SIGILL, sigill_handler );
    if( sigsetjmp( jmpbuf, 1 ) )
    {
        signal( SIGILL, oldsig );
        return 0;
    }

    canjump = 1;
    asm volatile( "mtspr 256, %0\n\t"
                  "vand 0, 0, 0\n\t"
                  :
                  : "r"(-1) );
    canjump = 0;

    signal( SIGILL, oldsig );

    return X264_CPU_ALTIVEC;
}
#endif

void     x264_cpu_restore( uint32_t cpu )
{
}

#else

uint32_t x264_cpu_detect( void )
{
    return 0;
}

void     x264_cpu_restore( uint32_t cpu )
{
}

#endif


int x264_cpu_num_processors( void )
{
#if !defined(HAVE_PTHREAD)
    return 1;

#elif defined(WIN32)
    return pthread_num_processors_np();

#elif defined(SYS_LINUX)
    unsigned int bit;
    int np;
    cpu_set_t p_aff;
    memset( &p_aff, 0, sizeof(p_aff) );
    sched_getaffinity( 0, sizeof(p_aff), &p_aff );
    for( np = 0, bit = 0; bit < sizeof(p_aff); bit++ )
        np += (((uint8_t *)&p_aff)[bit / 8] >> (bit % 8)) & 1;
    return np;

#elif defined(SYS_BEOS)
    system_info info;
    get_system_info( &info );
    return info.cpu_count;

#elif defined(SYS_MACOSX)
    int numberOfCPUs;
    size_t length = sizeof( numberOfCPUs );
    if( sysctlbyname("hw.ncpu", &numberOfCPUs, &length, NULL, 0) )
    {
        numberOfCPUs = 1;
    }
    return numberOfCPUs;

#else
    return 1;
#endif
}