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
arm_cpu_env_flags(int * flags)23 static 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
arm_cpu_env_mask(void)34 static 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
arm_cpu_caps(void)42 int 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_MEDIA
53 flags |= HAS_MEDIA;
54 #endif /* HAVE_MEDIA */
55 #if HAVE_NEON || HAVE_NEON_ASM
56 flags |= HAS_NEON;
57 #endif /* HAVE_NEON || HAVE_NEON_ASM */
58 return flags & mask;
59 }
60
61 #elif defined(_MSC_VER) /* end !CONFIG_RUNTIME_CPU_DETECT */
62 /*For GetExceptionCode() and EXCEPTION_ILLEGAL_INSTRUCTION.*/
63 #define WIN32_LEAN_AND_MEAN
64 #define WIN32_EXTRA_LEAN
65 #include <windows.h>
66
arm_cpu_caps(void)67 int arm_cpu_caps(void) {
68 int flags;
69 int mask;
70 if (!arm_cpu_env_flags(&flags)) {
71 return flags;
72 }
73 mask = arm_cpu_env_mask();
74 /* MSVC has no inline __asm support for ARM, but it does let you __emit
75 * instructions via their assembled hex code.
76 * All of these instructions should be essentially nops.
77 */
78 #if HAVE_MEDIA
79 if (mask & HAS_MEDIA)
80 __try {
81 /*SHADD8 r3,r3,r3*/
82 __emit(0xE6333F93);
83 flags |= HAS_MEDIA;
84 } __except (GetExceptionCode() == EXCEPTION_ILLEGAL_INSTRUCTION) {
85 /*Ignore exception.*/
86 }
87 }
88 #endif /* HAVE_MEDIA */
89 #if HAVE_NEON || HAVE_NEON_ASM
90 if (mask &HAS_NEON) {
91 __try {
92 /*VORR q0,q0,q0*/
93 __emit(0xF2200150);
94 flags |= HAS_NEON;
GetExceptionCode()95 } __except (GetExceptionCode() == EXCEPTION_ILLEGAL_INSTRUCTION) {
96 /*Ignore exception.*/
97 }
98 }
99 #endif /* HAVE_NEON || HAVE_NEON_ASM */
100 return flags & mask;
101 }
102
103 #elif defined(__ANDROID__) /* end _MSC_VER */
104 #include <cpu-features.h>
105
106 int arm_cpu_caps(void) {
107 int flags;
108 int mask;
109 uint64_t features;
110 if (!arm_cpu_env_flags(&flags)) {
111 return flags;
112 }
113 mask = arm_cpu_env_mask();
114 features = android_getCpuFeatures();
115
116 #if HAVE_MEDIA
117 flags |= HAS_MEDIA;
118 #endif /* HAVE_MEDIA */
119 #if HAVE_NEON || HAVE_NEON_ASM
120 if (features & ANDROID_CPU_ARM_FEATURE_NEON)
121 flags |= HAS_NEON;
122 #endif /* HAVE_NEON || HAVE_NEON_ASM */
123 return flags & mask;
124 }
125
126 #elif defined(__linux__) /* end __ANDROID__ */
127
128 #include <stdio.h>
129
130 int arm_cpu_caps(void) {
131 FILE *fin;
132 int flags;
133 int mask;
134 if (!arm_cpu_env_flags(&flags)) {
135 return flags;
136 }
137 mask = arm_cpu_env_mask();
138 /* Reading /proc/self/auxv would be easier, but that doesn't work reliably
139 * on Android.
140 * This also means that detection will fail in Scratchbox.
141 */
142 fin = fopen("/proc/cpuinfo", "r");
143 if (fin != NULL) {
144 /* 512 should be enough for anybody (it's even enough for all the flags
145 * that x86 has accumulated... so far).
146 */
147 char buf[512];
148 while (fgets(buf, 511, fin) != NULL) {
149 #if HAVE_NEON || HAVE_NEON_ASM
150 if (memcmp(buf, "Features", 8) == 0) {
151 char *p;
152 p = strstr(buf, " neon");
153 if (p != NULL && (p[5] == ' ' || p[5] == '\n')) {
154 flags |= HAS_NEON;
155 }
156 }
157 #endif /* HAVE_NEON || HAVE_NEON_ASM */
158 #if HAVE_MEDIA
159 if (memcmp(buf, "CPU architecture:", 17) == 0) {
160 int version;
161 version = atoi(buf + 17);
162 if (version >= 6) {
163 flags |= HAS_MEDIA;
164 }
165 }
166 #endif /* HAVE_MEDIA */
167 }
168 fclose(fin);
169 }
170 return flags & mask;
171 }
172 #else /* end __linux__ */
173 #error "--enable-runtime-cpu-detect selected, but no CPU detection method " \
174 "available for your platform. Reconfigure with --disable-runtime-cpu-detect."
175 #endif
176