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