1/*
2 *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3 *
4 *  Use of this source code is governed by a BSD-style license
5 *  that can be found in the LICENSE file in the root of the source
6 *  tree. An additional intellectual property rights grant can be found
7 *  in the file PATENTS.  All contributing project authors may
8 *  be found in the AUTHORS file in the root of the source tree.
9 */
10
11#include <stdlib.h>
12#include <string.h>
13#include "vpx_ports/arm.h"
14#include "./vpx_config.h"
15
16#ifdef WINAPI_FAMILY
17#include <winapifamily.h>
18#if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
19#define getenv(x) NULL
20#endif
21#endif
22
23static int arm_cpu_env_flags(int *flags) {
24  char *env;
25  env = getenv("VPX_SIMD_CAPS");
26  if (env && *env) {
27    *flags = (int)strtol(env, NULL, 0);
28    return 0;
29  }
30  *flags = 0;
31  return -1;
32}
33
34static int arm_cpu_env_mask(void) {
35  char *env;
36  env = getenv("VPX_SIMD_CAPS_MASK");
37  return env && *env ? (int)strtol(env, NULL, 0) : ~0;
38}
39
40#if !CONFIG_RUNTIME_CPU_DETECT
41
42int arm_cpu_caps(void) {
43  /* This function should actually be a no-op. There is no way to adjust any of
44   * these because the RTCD tables do not exist: the functions are called
45   * statically */
46  int flags;
47  int mask;
48  if (!arm_cpu_env_flags(&flags)) {
49    return flags;
50  }
51  mask = arm_cpu_env_mask();
52#if HAVE_EDSP
53  flags |= HAS_EDSP;
54#endif /* HAVE_EDSP */
55#if HAVE_MEDIA
56  flags |= HAS_MEDIA;
57#endif /* HAVE_MEDIA */
58#if HAVE_NEON || HAVE_NEON_ASM
59  flags |= HAS_NEON;
60#endif /* HAVE_NEON  || HAVE_NEON_ASM */
61  return flags & mask;
62}
63
64#elif defined(_MSC_VER) /* end !CONFIG_RUNTIME_CPU_DETECT */
65/*For GetExceptionCode() and EXCEPTION_ILLEGAL_INSTRUCTION.*/
66#define WIN32_LEAN_AND_MEAN
67#define WIN32_EXTRA_LEAN
68#include <windows.h>
69
70int arm_cpu_caps(void) {
71  int flags;
72  int mask;
73  if (!arm_cpu_env_flags(&flags)) {
74    return flags;
75  }
76  mask = arm_cpu_env_mask();
77  /* MSVC has no inline __asm support for ARM, but it does let you __emit
78   *  instructions via their assembled hex code.
79   * All of these instructions should be essentially nops.
80   */
81#if HAVE_EDSP
82  if (mask & HAS_EDSP) {
83    __try {
84      /*PLD [r13]*/
85      __emit(0xF5DDF000);
86      flags |= HAS_EDSP;
87    } __except (GetExceptionCode() == EXCEPTION_ILLEGAL_INSTRUCTION) {
88      /*Ignore exception.*/
89    }
90  }
91#endif /* HAVE_EDSP */
92#if HAVE_MEDIA
93  if (mask & HAS_MEDIA)
94    __try {
95      /*SHADD8 r3,r3,r3*/
96      __emit(0xE6333F93);
97      flags |= HAS_MEDIA;
98    } __except (GetExceptionCode() == EXCEPTION_ILLEGAL_INSTRUCTION) {
99    /*Ignore exception.*/
100  }
101}
102#endif /* HAVE_MEDIA */
103#if HAVE_NEON || HAVE_NEON_ASM
104if (mask &HAS_NEON) {
105  __try {
106    /*VORR q0,q0,q0*/
107    __emit(0xF2200150);
108    flags |= HAS_NEON;
109  } __except (GetExceptionCode() == EXCEPTION_ILLEGAL_INSTRUCTION) {
110    /*Ignore exception.*/
111  }
112}
113#endif /* HAVE_NEON || HAVE_NEON_ASM */
114return flags & mask;
115}
116
117#elif defined(__ANDROID__) /* end _MSC_VER */
118#include <cpu-features.h>
119
120int arm_cpu_caps(void) {
121  int flags;
122  int mask;
123  uint64_t features;
124  if (!arm_cpu_env_flags(&flags)) {
125    return flags;
126  }
127  mask = arm_cpu_env_mask();
128  features = android_getCpuFeatures();
129
130#if HAVE_EDSP
131  flags |= HAS_EDSP;
132#endif /* HAVE_EDSP */
133#if HAVE_MEDIA
134  flags |= HAS_MEDIA;
135#endif /* HAVE_MEDIA */
136#if HAVE_NEON || HAVE_NEON_ASM
137  if (features & ANDROID_CPU_ARM_FEATURE_NEON)
138    flags |= HAS_NEON;
139#endif /* HAVE_NEON || HAVE_NEON_ASM */
140  return flags & mask;
141}
142
143#elif defined(__linux__) /* end __ANDROID__ */
144
145#include <stdio.h>
146
147int arm_cpu_caps(void) {
148  FILE *fin;
149  int flags;
150  int mask;
151  if (!arm_cpu_env_flags(&flags)) {
152    return flags;
153  }
154  mask = arm_cpu_env_mask();
155  /* Reading /proc/self/auxv would be easier, but that doesn't work reliably
156   *  on Android.
157   * This also means that detection will fail in Scratchbox.
158   */
159  fin = fopen("/proc/cpuinfo", "r");
160  if (fin != NULL) {
161    /* 512 should be enough for anybody (it's even enough for all the flags
162     * that x86 has accumulated... so far).
163     */
164    char buf[512];
165    while (fgets(buf, 511, fin) != NULL) {
166#if HAVE_EDSP || HAVE_NEON || HAVE_NEON_ASM
167      if (memcmp(buf, "Features", 8) == 0) {
168        char *p;
169#if HAVE_EDSP
170        p = strstr(buf, " edsp");
171        if (p != NULL && (p[5] == ' ' || p[5] == '\n')) {
172          flags |= HAS_EDSP;
173        }
174#endif /* HAVE_EDSP */
175#if HAVE_NEON || HAVE_NEON_ASM
176        p = strstr(buf, " neon");
177        if (p != NULL && (p[5] == ' ' || p[5] == '\n')) {
178          flags |= HAS_NEON;
179        }
180#endif /* HAVE_NEON || HAVE_NEON_ASM */
181      }
182#endif /* HAVE_EDSP || HAVE_NEON || HAVE_NEON_ASM */
183#if HAVE_MEDIA
184      if (memcmp(buf, "CPU architecture:", 17) == 0) {
185        int version;
186        version = atoi(buf + 17);
187        if (version >= 6) {
188          flags |= HAS_MEDIA;
189        }
190      }
191#endif /* HAVE_MEDIA */
192    }
193    fclose(fin);
194  }
195  return flags & mask;
196}
197#else /* end __linux__ */
198#error "--enable-runtime-cpu-detect selected, but no CPU detection method " \
199"available for your platform. Reconfigure with --disable-runtime-cpu-detect."
200#endif
201