1 /* Copyright (c) 2010 Xiph.Org Foundation
2  * Copyright (c) 2013 Parrot */
3 /*
4    Redistribution and use in source and binary forms, with or without
5    modification, are permitted provided that the following conditions
6    are met:
7 
8    - Redistributions of source code must retain the above copyright
9    notice, this list of conditions and the following disclaimer.
10 
11    - Redistributions in binary form must reproduce the above copyright
12    notice, this list of conditions and the following disclaimer in the
13    documentation and/or other materials provided with the distribution.
14 
15    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
19    OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
22    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
23    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
24    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27 
28 /* Original code from libtheora modified to suit to Opus */
29 
30 #ifdef HAVE_CONFIG_H
31 #include "config.h"
32 #endif
33 
34 #ifdef OPUS_HAVE_RTCD
35 
36 #include "armcpu.h"
37 #include "cpu_support.h"
38 #include "os_support.h"
39 #include "opus_types.h"
40 #include "arch.h"
41 
42 #define OPUS_CPU_ARM_V4_FLAG    (1<<OPUS_ARCH_ARM_V4)
43 #define OPUS_CPU_ARM_EDSP_FLAG  (1<<OPUS_ARCH_ARM_EDSP)
44 #define OPUS_CPU_ARM_MEDIA_FLAG (1<<OPUS_ARCH_ARM_MEDIA)
45 #define OPUS_CPU_ARM_NEON_FLAG  (1<<OPUS_ARCH_ARM_NEON)
46 
47 #if defined(_MSC_VER)
48 /*For GetExceptionCode() and EXCEPTION_ILLEGAL_INSTRUCTION.*/
49 # define WIN32_LEAN_AND_MEAN
50 # define WIN32_EXTRA_LEAN
51 # include <windows.h>
52 
opus_cpu_capabilities(void)53 static OPUS_INLINE opus_uint32 opus_cpu_capabilities(void){
54   opus_uint32 flags;
55   flags=0;
56   /* MSVC has no OPUS_INLINE __asm support for ARM, but it does let you __emit
57    * instructions via their assembled hex code.
58    * All of these instructions should be essentially nops. */
59 # if defined(OPUS_ARM_MAY_HAVE_EDSP) || defined(OPUS_ARM_MAY_HAVE_MEDIA) \
60  || defined(OPUS_ARM_MAY_HAVE_NEON) || defined(OPUS_ARM_MAY_HAVE_NEON_INTR)
61   __try{
62     /*PLD [r13]*/
63     __emit(0xF5DDF000);
64     flags|=OPUS_CPU_ARM_EDSP_FLAG;
65   }
66   __except(GetExceptionCode()==EXCEPTION_ILLEGAL_INSTRUCTION){
67     /*Ignore exception.*/
68   }
69 #  if defined(OPUS_ARM_MAY_HAVE_MEDIA) \
70  || defined(OPUS_ARM_MAY_HAVE_NEON) || defined(OPUS_ARM_MAY_HAVE_NEON_INTR)
71   __try{
72     /*SHADD8 r3,r3,r3*/
73     __emit(0xE6333F93);
74     flags|=OPUS_CPU_ARM_MEDIA_FLAG;
75   }
76   __except(GetExceptionCode()==EXCEPTION_ILLEGAL_INSTRUCTION){
77     /*Ignore exception.*/
78   }
79 #   if defined(OPUS_ARM_MAY_HAVE_NEON) || defined(OPUS_ARM_MAY_HAVE_NEON_INTR)
80   __try{
81     /*VORR q0,q0,q0*/
82     __emit(0xF2200150);
83     flags|=OPUS_CPU_ARM_NEON_FLAG;
84   }
85   __except(GetExceptionCode()==EXCEPTION_ILLEGAL_INSTRUCTION){
86     /*Ignore exception.*/
87   }
88 #   endif
89 #  endif
90 # endif
91   return flags;
92 }
93 
94 #elif defined(__linux__)
95 /* Linux based */
96 #include <stdio.h>
97 
opus_cpu_capabilities(void)98 opus_uint32 opus_cpu_capabilities(void)
99 {
100   opus_uint32 flags = 0;
101   FILE *cpuinfo;
102 
103   /* Reading /proc/self/auxv would be easier, but that doesn't work reliably on
104    * Android */
105   cpuinfo = fopen("/proc/cpuinfo", "r");
106 
107   if(cpuinfo != NULL)
108   {
109     /* 512 should be enough for anybody (it's even enough for all the flags that
110      * x86 has accumulated... so far). */
111     char buf[512];
112 
113     while(fgets(buf, 512, cpuinfo) != NULL)
114     {
115 # if defined(OPUS_ARM_MAY_HAVE_EDSP) || defined(OPUS_ARM_MAY_HAVE_MEDIA) \
116  || defined(OPUS_ARM_MAY_HAVE_NEON) || defined(OPUS_ARM_MAY_HAVE_NEON_INTR)
117       /* Search for edsp and neon flag */
118       if(memcmp(buf, "Features", 8) == 0)
119       {
120         char *p;
121         p = strstr(buf, " edsp");
122         if(p != NULL && (p[5] == ' ' || p[5] == '\n'))
123           flags |= OPUS_CPU_ARM_EDSP_FLAG;
124 
125 #  if defined(OPUS_ARM_MAY_HAVE_NEON) || defined(OPUS_ARM_MAY_HAVE_NEON_INTR)
126         p = strstr(buf, " neon");
127         if(p != NULL && (p[5] == ' ' || p[5] == '\n'))
128           flags |= OPUS_CPU_ARM_NEON_FLAG;
129 #  endif
130       }
131 # endif
132 
133 # if defined(OPUS_ARM_MAY_HAVE_MEDIA) \
134  || defined(OPUS_ARM_MAY_HAVE_NEON) || defined(OPUS_ARM_MAY_HAVE_NEON_INTR)
135       /* Search for media capabilities (>= ARMv6) */
136       if(memcmp(buf, "CPU architecture:", 17) == 0)
137       {
138         int version;
139         version = atoi(buf+17);
140 
141         if(version >= 6)
142           flags |= OPUS_CPU_ARM_MEDIA_FLAG;
143       }
144 # endif
145     }
146 
147     fclose(cpuinfo);
148   }
149   return flags;
150 }
151 #else
152 /* The feature registers which can tell us what the processor supports are
153  * accessible in priveleged modes only, so we can't have a general user-space
154  * detection method like on x86.*/
155 # error "Configured to use ARM asm but no CPU detection method available for " \
156    "your platform.  Reconfigure with --disable-rtcd (or send patches)."
157 #endif
158 
opus_select_arch(void)159 int opus_select_arch(void)
160 {
161   opus_uint32 flags = opus_cpu_capabilities();
162   int arch = 0;
163 
164   if(!(flags & OPUS_CPU_ARM_EDSP_FLAG)) {
165     /* Asserts ensure arch values are sequential */
166     celt_assert(arch == OPUS_ARCH_ARM_V4);
167     return arch;
168   }
169   arch++;
170 
171   if(!(flags & OPUS_CPU_ARM_MEDIA_FLAG)) {
172     celt_assert(arch == OPUS_ARCH_ARM_EDSP);
173     return arch;
174   }
175   arch++;
176 
177   if(!(flags & OPUS_CPU_ARM_NEON_FLAG)) {
178     celt_assert(arch == OPUS_ARCH_ARM_MEDIA);
179     return arch;
180   }
181   arch++;
182 
183   celt_assert(arch == OPUS_ARCH_ARM_NEON);
184   return arch;
185 }
186 
187 #endif
188