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 ( "push %%rbx\n\t" \
100 # define cpuid( reg ) \
101 asm volatile ( "push %%ebx\n\t" \
103 "movl %%ebx,%1\n\t" \
113 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
114 && defined( HAVE_SIGNAL_H )
115 void (*pf_sigill) (int) = signal( SIGILL, SigHandler );
118 i_capabilities |= CPU_CAPABILITY_FPU;
120 # if defined( __i386__ )
121 /* check if cpuid instruction is supported */
122 asm volatile ( "push %%ebx\n\t"
125 "movl %%eax, %%ebx\n\t"
126 "xorl $0x200000, %%eax\n\t"
140 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
141 && defined( HAVE_SIGNAL_H )
142 signal( SIGILL, pf_sigill );
144 return i_capabilities;
147 /* x86_64 supports cpuid instruction, so we dont need to check it */
150 i_capabilities |= CPU_CAPABILITY_486;
152 /* the CPU supports the CPUID instruction - get its level */
157 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
158 && defined( HAVE_SIGNAL_H )
159 signal( SIGILL, pf_sigill );
161 return i_capabilities;
164 /* FIXME: this isn't correct, since some 486s have cpuid */
165 i_capabilities |= CPU_CAPABILITY_586;
167 /* borrowed from mpeg2dec */
168 b_amd = ( i_ebx == 0x68747541 ) && ( i_ecx == 0x444d4163 )
169 && ( i_edx == 0x69746e65 );
171 /* test for the MMX flag */
174 if( ! (i_edx & 0x00800000) )
176 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
177 && defined( HAVE_SIGNAL_H )
178 signal( SIGILL, pf_sigill );
180 return i_capabilities;
183 i_capabilities |= CPU_CAPABILITY_MMX;
185 if( i_edx & 0x02000000 )
187 i_capabilities |= CPU_CAPABILITY_MMXEXT;
189 # ifdef CAN_COMPILE_SSE
190 /* We test if OS supports the SSE instructions */
191 psz_capability = "SSE";
194 if( setjmp( env ) == 0 )
196 /* Test a SSE instruction */
197 __asm__ __volatile__ ( "xorps %%xmm0,%%xmm0\n" : : );
202 i_capabilities |= CPU_CAPABILITY_SSE;
207 if( i_edx & 0x04000000 )
209 # if defined(CAN_COMPILE_SSE)
210 /* We test if OS supports the SSE instructions */
211 psz_capability = "SSE2";
214 if( setjmp( env ) == 0 )
216 /* Test a SSE2 instruction */
217 __asm__ __volatile__ ( "movupd %%xmm0, %%xmm0\n" : : );
222 i_capabilities |= CPU_CAPABILITY_SSE2;
227 /* test for additional capabilities */
230 if( i_eax < 0x80000001 )
232 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
233 && defined( HAVE_SIGNAL_H )
234 signal( SIGILL, pf_sigill );
236 return i_capabilities;
239 /* list these additional capabilities */
242 # ifdef CAN_COMPILE_3DNOW
243 if( i_edx & 0x80000000 )
245 psz_capability = "3D Now!";
248 if( setjmp( env ) == 0 )
250 /* Test a 3D Now! instruction */
251 __asm__ __volatile__ ( "pfadd %%mm0,%%mm0\n" "femms\n" : : );
256 i_capabilities |= CPU_CAPABILITY_3DNOW;
261 if( b_amd && ( i_edx & 0x00400000 ) )
263 i_capabilities |= CPU_CAPABILITY_MMXEXT;
266 # if defined( CAN_COMPILE_SSE ) || defined ( CAN_COMPILE_3DNOW ) \
267 && defined( HAVE_SIGNAL_H )
268 signal( SIGILL, pf_sigill );
270 return i_capabilities;
272 #elif defined( __powerpc__ )
274 # ifdef CAN_COMPILE_ALTIVEC && defined( HAVE_SIGNAL_H )
275 void (*pf_sigill) (int) = signal( SIGILL, SigHandler );
277 i_capabilities |= CPU_CAPABILITY_FPU;
281 if( setjmp( env ) == 0 )
283 asm volatile ("mtspr 256, %0\n\t"
284 "vand %%v0, %%v0, %%v0"
291 i_capabilities |= CPU_CAPABILITY_ALTIVEC;
294 signal( SIGILL, pf_sigill );
297 return i_capabilities;
299 #elif defined( __sparc__ )
301 i_capabilities |= CPU_CAPABILITY_FPU;
302 return i_capabilities;
304 #elif defined( _MSC_VER ) && !defined( UNDER_CE )
305 i_capabilities |= CPU_CAPABILITY_FPU;
306 return i_capabilities;
309 /* default behaviour */
310 return i_capabilities;
315 /*****************************************************************************
316 * SigHandler: system signal handler
317 *****************************************************************************
318 * This function is called when an illegal instruction signal is received by
319 * the program. We use this function to test OS and CPU capabilities
320 *****************************************************************************/
321 #if defined( HAVE_SIGNAL_H )
322 static void SigHandler( int i_signal )
324 /* Acknowledge the signal received */
328 sigrelse( i_signal );
331 #if defined( __i386__ )
332 fprintf( stderr, "warning: your CPU has %s instructions, but not your "
333 "operating system.\n", psz_capability );
334 fprintf( stderr, " some optimizations will be disabled unless "
335 "you upgrade your OS\n" );
336 # if defined( SYS_LINUX )
337 fprintf( stderr, " (for instance Linux kernel 2.4.x or later)\n" );