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 14 #include "./vpx_config.h" 15 #include "vpx_ports/arm.h" 16 17 #ifdef WINAPI_FAMILY 18 #include <winapifamily.h> 19 #if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP) 20 #define getenv(x) NULL 21 #endif 22 #endif 23 24 static int arm_cpu_env_flags(int *flags) { 25 char *env; 26 env = getenv("VPX_SIMD_CAPS"); 27 if (env && *env) { 28 *flags = (int)strtol(env, NULL, 0); 29 return 0; 30 } 31 *flags = 0; 32 return -1; 33 } 34 35 static int arm_cpu_env_mask(void) { 36 char *env; 37 env = getenv("VPX_SIMD_CAPS_MASK"); 38 return env && *env ? (int)strtol(env, NULL, 0) : ~0; 39 } 40 41 #if !CONFIG_RUNTIME_CPU_DETECT 42 43 int arm_cpu_caps(void) { 44 /* This function should actually be a no-op. There is no way to adjust any of 45 * these because the RTCD tables do not exist: the functions are called 46 * statically */ 47 int flags; 48 int mask; 49 if (!arm_cpu_env_flags(&flags)) { 50 return flags; 51 } 52 mask = arm_cpu_env_mask(); 53 #if HAVE_NEON || HAVE_NEON_ASM 54 flags |= HAS_NEON; 55 #endif /* HAVE_NEON || HAVE_NEON_ASM */ 56 return flags & mask; 57 } 58 59 #elif defined(_MSC_VER) /* end !CONFIG_RUNTIME_CPU_DETECT */ 60 /*For GetExceptionCode() and EXCEPTION_ILLEGAL_INSTRUCTION.*/ 61 #ifndef WIN32_LEAN_AND_MEAN 62 #define WIN32_LEAN_AND_MEAN 63 #endif 64 #ifndef WIN32_EXTRA_LEAN 65 #define WIN32_EXTRA_LEAN 66 #endif 67 #include <windows.h> 68 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_NEON || HAVE_NEON_ASM 81 if (mask & HAS_NEON) { 82 __try { 83 /*VORR q0,q0,q0*/ 84 __emit(0xF2200150); 85 flags |= HAS_NEON; 86 } __except (GetExceptionCode() == EXCEPTION_ILLEGAL_INSTRUCTION) { 87 /*Ignore exception.*/ 88 } 89 } 90 #endif /* HAVE_NEON || HAVE_NEON_ASM */ 91 return flags & mask; 92 } 93 94 #elif defined(__ANDROID__) /* end _MSC_VER */ 95 #include <cpu-features.h> 96 97 int arm_cpu_caps(void) { 98 int flags; 99 int mask; 100 uint64_t features; 101 if (!arm_cpu_env_flags(&flags)) { 102 return flags; 103 } 104 mask = arm_cpu_env_mask(); 105 features = android_getCpuFeatures(); 106 107 #if HAVE_NEON || HAVE_NEON_ASM 108 if (features & ANDROID_CPU_ARM_FEATURE_NEON) flags |= HAS_NEON; 109 #endif /* HAVE_NEON || HAVE_NEON_ASM */ 110 return flags & mask; 111 } 112 113 #elif defined(__linux__) /* end __ANDROID__ */ 114 115 #include <stdio.h> 116 117 int arm_cpu_caps(void) { 118 FILE *fin; 119 int flags; 120 int mask; 121 if (!arm_cpu_env_flags(&flags)) { 122 return flags; 123 } 124 mask = arm_cpu_env_mask(); 125 /* Reading /proc/self/auxv would be easier, but that doesn't work reliably 126 * on Android. 127 * This also means that detection will fail in Scratchbox. 128 */ 129 fin = fopen("/proc/cpuinfo", "r"); 130 if (fin != NULL) { 131 /* 512 should be enough for anybody (it's even enough for all the flags 132 * that x86 has accumulated... so far). 133 */ 134 char buf[512]; 135 while (fgets(buf, 511, fin) != NULL) { 136 #if HAVE_NEON || HAVE_NEON_ASM 137 if (memcmp(buf, "Features", 8) == 0) { 138 char *p; 139 p = strstr(buf, " neon"); 140 if (p != NULL && (p[5] == ' ' || p[5] == '\n')) { 141 flags |= HAS_NEON; 142 } 143 } 144 #endif /* HAVE_NEON || HAVE_NEON_ASM */ 145 } 146 fclose(fin); 147 } 148 return flags & mask; 149 } 150 #else /* end __linux__ */ 151 #error \ 152 "--enable-runtime-cpu-detect selected, but no CPU detection method " \ 153 "available for your platform. Reconfigure with --disable-runtime-cpu-detect." 154 #endif 155