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 
41 #define OPUS_CPU_ARM_V4    (1)
42 #define OPUS_CPU_ARM_EDSP  (1<<1)
43 #define OPUS_CPU_ARM_MEDIA (1<<2)
44 #define OPUS_CPU_ARM_NEON  (1<<3)
45 
46 #if defined(_MSC_VER)
47 /*For GetExceptionCode() and EXCEPTION_ILLEGAL_INSTRUCTION.*/
48 # define WIN32_LEAN_AND_MEAN
49 # define WIN32_EXTRA_LEAN
50 # include <windows.h>
51 
opus_cpu_capabilities(void)52 static OPUS_INLINE opus_uint32 opus_cpu_capabilities(void){
53   opus_uint32 flags;
54   flags=0;
55   /* MSVC has no OPUS_INLINE __asm support for ARM, but it does let you __emit
56    * instructions via their assembled hex code.
57    * All of these instructions should be essentially nops. */
58 # if defined(OPUS_ARM_MAY_HAVE_EDSP)
59   __try{
60     /*PLD [r13]*/
61     __emit(0xF5DDF000);
62     flags|=OPUS_CPU_ARM_EDSP;
63   }
64   __except(GetExceptionCode()==EXCEPTION_ILLEGAL_INSTRUCTION){
65     /*Ignore exception.*/
66   }
67 #  if defined(OPUS_ARM_MAY_HAVE_MEDIA)
68   __try{
69     /*SHADD8 r3,r3,r3*/
70     __emit(0xE6333F93);
71     flags|=OPUS_CPU_ARM_MEDIA;
72   }
73   __except(GetExceptionCode()==EXCEPTION_ILLEGAL_INSTRUCTION){
74     /*Ignore exception.*/
75   }
76 #   if defined(OPUS_ARM_MAY_HAVE_NEON)
77   __try{
78     /*VORR q0,q0,q0*/
79     __emit(0xF2200150);
80     flags|=OPUS_CPU_ARM_NEON;
81   }
82   __except(GetExceptionCode()==EXCEPTION_ILLEGAL_INSTRUCTION){
83     /*Ignore exception.*/
84   }
85 #   endif
86 #  endif
87 # endif
88   return flags;
89 }
90 
91 #elif defined(__linux__)
92 /* Linux based */
opus_cpu_capabilities(void)93 opus_uint32 opus_cpu_capabilities(void)
94 {
95   opus_uint32 flags = 0;
96   FILE *cpuinfo;
97 
98   /* Reading /proc/self/auxv would be easier, but that doesn't work reliably on
99    * Android */
100   cpuinfo = fopen("/proc/cpuinfo", "r");
101 
102   if(cpuinfo != NULL)
103   {
104     /* 512 should be enough for anybody (it's even enough for all the flags that
105      * x86 has accumulated... so far). */
106     char buf[512];
107 
108     while(fgets(buf, 512, cpuinfo) != NULL)
109     {
110 # if defined(OPUS_ARM_MAY_HAVE_EDSP) || defined(OPUS_ARM_MAY_HAVE_NEON)
111       /* Search for edsp and neon flag */
112       if(memcmp(buf, "Features", 8) == 0)
113       {
114         char *p;
115 #  if defined(OPUS_ARM_MAY_HAVE_EDSP)
116         p = strstr(buf, " edsp");
117         if(p != NULL && (p[5] == ' ' || p[5] == '\n'))
118           flags |= OPUS_CPU_ARM_EDSP;
119 #  endif
120 
121 #  if defined(OPUS_ARM_MAY_HAVE_NEON)
122         p = strstr(buf, " neon");
123         if(p != NULL && (p[5] == ' ' || p[5] == '\n'))
124           flags |= OPUS_CPU_ARM_NEON;
125 #  endif
126       }
127 # endif
128 
129 # if defined(OPUS_ARM_MAY_HAVE_MEDIA)
130       /* Search for media capabilities (>= ARMv6) */
131       if(memcmp(buf, "CPU architecture:", 17) == 0)
132       {
133         int version;
134         version = atoi(buf+17);
135 
136         if(version >= 6)
137           flags |= OPUS_CPU_ARM_MEDIA;
138       }
139 # endif
140     }
141 
142     fclose(cpuinfo);
143   }
144   return flags;
145 }
146 #else
147 /* The feature registers which can tell us what the processor supports are
148  * accessible in priveleged modes only, so we can't have a general user-space
149  * detection method like on x86.*/
150 # error "Configured to use ARM asm but no CPU detection method available for " \
151    "your platform.  Reconfigure with --disable-rtcd (or send patches)."
152 #endif
153 
opus_select_arch(void)154 int opus_select_arch(void)
155 {
156   opus_uint32 flags = opus_cpu_capabilities();
157   int arch = 0;
158 
159   if(!(flags & OPUS_CPU_ARM_EDSP))
160     return arch;
161   arch++;
162 
163   if(!(flags & OPUS_CPU_ARM_MEDIA))
164     return arch;
165   arch++;
166 
167   if(!(flags & OPUS_CPU_ARM_NEON))
168     return arch;
169   arch++;
170 
171   return arch;
172 }
173 
174 #endif
175