1 /*****************************************************************************
2 * cpu.c: CPU detection code
3 *****************************************************************************
4 * Copyright (C) 1998-2004 the VideoLAN team
7 * Authors: Samuel Hocevar <sam@zoy.org>
8 * Christophe Massiot <massiot@via.ecp.fr>
9 * Eugenio Jarosiewicz <ej0@cise.ufl.eduEujenio>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
24 *****************************************************************************/
26 /*****************************************************************************
28 *****************************************************************************/
32 # include <signal.h> /* SIGHUP, SIGINT, SIGKILL */
33 # include <setjmp.h> /* longjmp, setjmp */
37 #include <sys/sysctl.h>
42 /*****************************************************************************
44 *****************************************************************************/
46 static void SigHandler ( int );
49 /*****************************************************************************
50 * Global variables - they're needed for signal handling
51 *****************************************************************************/
55 #if defined( __i386__ ) || defined( __x86_64__ )
56 static char *psz_capability;
60 /*****************************************************************************
61 * CPUCapabilities: get the CPU capabilities
62 *****************************************************************************
63 * This function is called to list extensions the CPU may have.
64 *****************************************************************************/
65 uint32_t CPUCapabilities( void )
67 volatile uint32_t i_capabilities = CPU_CAPABILITY_NONE;
69 #if defined( SYS_DARWIN )
70 int selectors[2] = { CTL_HW, HW_VECTORUNIT };
71 int i_has_altivec = 0;
72 size_t i_length = sizeof( i_has_altivec );
73 int i_error = sysctl( selectors, 2, &i_has_altivec, &i_length, NULL, 0);
75 i_capabilities |= CPU_CAPABILITY_FPU;
77 if( i_error == 0 && i_has_altivec != 0 )
78 i_capabilities |= CPU_CAPABILITY_ALTIVEC;
80 return i_capabilities;
82 #elif defined( __i386__ ) || defined( __x86_64__ )
83 volatile unsigned int i_eax, i_ebx, i_ecx, i_edx;
84 volatile vlc_bool_t b_amd;
86 /* Needed for x86 CPU capabilities detection */
87 # if defined( __x86_64__ )
88 # define cpuid( reg ) \
89 asm volatile ( "cpuid\n\t" \
98 # define cpuid( reg ) \
99 asm volatile ( "push %%ebx\n\t" \
101 "movl %%ebx,%1\n\t" \
111 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
112 && defined( HAVE_SIGNAL_H )
113 void (*pf_sigill) (int) = signal( SIGILL, SigHandler );
116 i_capabilities |= CPU_CAPABILITY_FPU;
118 # if defined( __i386__ )
119 /* check if cpuid instruction is supported */
120 asm volatile ( "push %%ebx\n\t"
123 "movl %%eax, %%ebx\n\t"
124 "xorl $0x200000, %%eax\n\t"
138 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
139 && defined( HAVE_SIGNAL_H )
140 signal( SIGILL, pf_sigill );
142 return i_capabilities;
145 /* x86_64 supports cpuid instruction, so we dont need to check it */
148 i_capabilities |= CPU_CAPABILITY_486;
150 /* the CPU supports the CPUID instruction - get its level */
155 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
156 && defined( HAVE_SIGNAL_H )
157 signal( SIGILL, pf_sigill );
159 return i_capabilities;
162 /* FIXME: this isn't correct, since some 486s have cpuid */
163 i_capabilities |= CPU_CAPABILITY_586;
165 /* borrowed from mpeg2dec */
166 b_amd = ( i_ebx == 0x68747541 ) && ( i_ecx == 0x444d4163 )
167 && ( i_edx == 0x69746e65 );
169 /* test for the MMX flag */
172 if( ! (i_edx & 0x00800000) )
174 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
175 && defined( HAVE_SIGNAL_H )
176 signal( SIGILL, pf_sigill );
178 return i_capabilities;
181 i_capabilities |= CPU_CAPABILITY_MMX;
183 if( i_edx & 0x02000000 )
185 i_capabilities |= CPU_CAPABILITY_MMXEXT;
187 # ifdef CAN_COMPILE_SSE
188 /* We test if OS supports the SSE instructions */
189 psz_capability = "SSE";
192 if( setjmp( env ) == 0 )
194 /* Test a SSE instruction */
195 __asm__ __volatile__ ( "xorps %%xmm0,%%xmm0\n" : : );
200 i_capabilities |= CPU_CAPABILITY_SSE;
205 if( i_edx & 0x04000000 )
207 # if defined(CAN_COMPILE_SSE)
208 /* We test if OS supports the SSE instructions */
209 psz_capability = "SSE2";
212 if( setjmp( env ) == 0 )
214 /* Test a SSE2 instruction */
215 __asm__ __volatile__ ( "movupd %%xmm0, %%xmm0\n" : : );
220 i_capabilities |= CPU_CAPABILITY_SSE2;
225 /* test for additional capabilities */
228 if( i_eax < 0x80000001 )
230 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
231 && defined( HAVE_SIGNAL_H )
232 signal( SIGILL, pf_sigill );
234 return i_capabilities;
237 /* list these additional capabilities */
240 # ifdef CAN_COMPILE_3DNOW
241 if( i_edx & 0x80000000 )
243 psz_capability = "3D Now!";
246 if( setjmp( env ) == 0 )
248 /* Test a 3D Now! instruction */
249 __asm__ __volatile__ ( "pfadd %%mm0,%%mm0\n" "femms\n" : : );
254 i_capabilities |= CPU_CAPABILITY_3DNOW;
259 if( b_amd && ( i_edx & 0x00400000 ) )
261 i_capabilities |= CPU_CAPABILITY_MMXEXT;
264 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
265 && defined( HAVE_SIGNAL_H )
266 signal( SIGILL, pf_sigill );
268 return i_capabilities;
270 #elif defined( __powerpc__ )
272 # ifdef CAN_COMPILE_ALTIVEC && defined( HAVE_SIGNAL_H )
273 void (*pf_sigill) (int) = signal( SIGILL, SigHandler );
275 i_capabilities |= CPU_CAPABILITY_FPU;
279 if( setjmp( env ) == 0 )
281 asm volatile ("mtspr 256, %0\n\t"
282 "vand %%v0, %%v0, %%v0"
289 i_capabilities |= CPU_CAPABILITY_ALTIVEC;
292 signal( SIGILL, pf_sigill );
295 return i_capabilities;
297 #elif defined( __sparc__ )
299 i_capabilities |= CPU_CAPABILITY_FPU;
300 return i_capabilities;
302 #elif defined( _MSC_VER ) && !defined( UNDER_CE )
303 i_capabilities |= CPU_CAPABILITY_FPU;
304 return i_capabilities;
307 /* default behaviour */
308 return i_capabilities;
313 /*****************************************************************************
314 * SigHandler: system signal handler
315 *****************************************************************************
316 * This function is called when an illegal instruction signal is received by
317 * the program. We use this function to test OS and CPU capabilities
318 *****************************************************************************/
319 #if defined( HAVE_SIGNAL_H )
320 static void SigHandler( int i_signal )
322 /* Acknowledge the signal received */
326 sigrelse( i_signal );
329 #if defined( __i386__ )
330 fprintf( stderr, "warning: your CPU has %s instructions, but not your "
331 "operating system.\n", psz_capability );
332 fprintf( stderr, " some optimizations will be disabled unless "
333 "you upgrade your OS\n" );
334 # if defined( SYS_LINUX )
335 fprintf( stderr, " (for instance Linux kernel 2.4.x or later)\n" );