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
52static 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 */
93opus_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
154int 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