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