1 /* 2 * Copyright 2011 The LibYuv 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 "libyuv/cpu_id.h" 12 13 #ifdef _MSC_VER 14 #include <intrin.h> // For __cpuidex() 15 #endif 16 #if !defined(__pnacl__) && !defined(__CLR_VER) && \ 17 !defined(__native_client__) && defined(_M_X64) && \ 18 defined(_MSC_VER) && (_MSC_FULL_VER >= 160040219) 19 #include <immintrin.h> // For _xgetbv() 20 #endif 21 22 #if !defined(__native_client__) 23 #include <stdlib.h> // For getenv() 24 #endif 25 26 // For ArmCpuCaps() but unittested on all platforms 27 #include <stdio.h> 28 #include <string.h> 29 30 #include "libyuv/basic_types.h" // For CPU_X86 31 32 #ifdef __cplusplus 33 namespace libyuv { 34 extern "C" { 35 #endif 36 37 // For functions that use the stack and have runtime checks for overflow, 38 // use SAFEBUFFERS to avoid additional check. 39 #if defined(_MSC_VER) && (_MSC_FULL_VER >= 160040219) 40 #define SAFEBUFFERS __declspec(safebuffers) 41 #else 42 #define SAFEBUFFERS 43 #endif 44 45 // Low level cpuid for X86. Returns zeros on other CPUs. 46 #if !defined(__pnacl__) && !defined(__CLR_VER) && \ 47 (defined(_M_IX86) || defined(_M_X64) || \ 48 defined(__i386__) || defined(__x86_64__)) 49 LIBYUV_API 50 void CpuId(uint32 info_eax, uint32 info_ecx, uint32* cpu_info) { 51 #if defined(_MSC_VER) 52 #if (_MSC_FULL_VER >= 160040219) 53 __cpuidex((int*)(cpu_info), info_eax, info_ecx); 54 #elif defined(_M_IX86) 55 __asm { 56 mov eax, info_eax 57 mov ecx, info_ecx 58 mov edi, cpu_info 59 cpuid 60 mov [edi], eax 61 mov [edi + 4], ebx 62 mov [edi + 8], ecx 63 mov [edi + 12], edx 64 } 65 #else 66 if (info_ecx == 0) { 67 __cpuid((int*)(cpu_info), info_eax); 68 } else { 69 cpu_info[3] = cpu_info[2] = cpu_info[1] = cpu_info[0] = 0; 70 } 71 #endif 72 #else // defined(_MSC_VER) 73 uint32 info_ebx, info_edx; 74 asm volatile ( // NOLINT 75 #if defined( __i386__) && defined(__PIC__) 76 // Preserve ebx for fpic 32 bit. 77 "mov %%ebx, %%edi \n" 78 "cpuid \n" 79 "xchg %%edi, %%ebx \n" 80 : "=D" (info_ebx), 81 #else 82 "cpuid \n" 83 : "=b" (info_ebx), 84 #endif // defined( __i386__) && defined(__PIC__) 85 "+a" (info_eax), "+c" (info_ecx), "=d" (info_edx)); 86 cpu_info[0] = info_eax; 87 cpu_info[1] = info_ebx; 88 cpu_info[2] = info_ecx; 89 cpu_info[3] = info_edx; 90 #endif // defined(_MSC_VER) 91 } 92 93 #if !defined(__native_client__) 94 #define HAS_XGETBV 95 // X86 CPUs have xgetbv to detect OS saves high parts of ymm registers. 96 int TestOsSaveYmm() { 97 uint32 xcr0 = 0u; 98 #if defined(_MSC_VER) && (_MSC_FULL_VER >= 160040219) 99 xcr0 = (uint32)(_xgetbv(0)); // VS2010 SP1 required. 100 #elif defined(_M_IX86) 101 __asm { 102 xor ecx, ecx // xcr 0 103 _asm _emit 0x0f _asm _emit 0x01 _asm _emit 0xd0 // For VS2010 and earlier. 104 mov xcr0, eax 105 } 106 #elif defined(__i386__) || defined(__x86_64__) 107 asm(".byte 0x0f, 0x01, 0xd0" : "=a" (xcr0) : "c" (0) : "%edx"); 108 #endif // defined(_MSC_VER) 109 return((xcr0 & 6) == 6); // Is ymm saved? 110 } 111 #endif // !defined(__native_client__) 112 #else 113 LIBYUV_API 114 void CpuId(uint32 eax, uint32 ecx, uint32* cpu_info) { 115 cpu_info[0] = cpu_info[1] = cpu_info[2] = cpu_info[3] = 0; 116 } 117 #endif 118 119 // based on libvpx arm_cpudetect.c 120 // For Arm, but public to allow testing on any CPU 121 LIBYUV_API SAFEBUFFERS 122 int ArmCpuCaps(const char* cpuinfo_name) { 123 char cpuinfo_line[512]; 124 FILE* f = fopen(cpuinfo_name, "r"); 125 if (!f) { 126 // Assume Neon if /proc/cpuinfo is unavailable. 127 // This will occur for Chrome sandbox for Pepper or Render process. 128 return kCpuHasNEON; 129 } 130 while (fgets(cpuinfo_line, sizeof(cpuinfo_line) - 1, f)) { 131 if (memcmp(cpuinfo_line, "Features", 8) == 0) { 132 char* p = strstr(cpuinfo_line, " neon"); 133 if (p && (p[5] == ' ' || p[5] == '\n')) { 134 fclose(f); 135 return kCpuHasNEON; 136 } 137 } 138 } 139 fclose(f); 140 return 0; 141 } 142 143 #if defined(__mips__) && defined(__linux__) 144 static int MipsCpuCaps(const char* search_string) { 145 char cpuinfo_line[512]; 146 const char* file_name = "/proc/cpuinfo"; 147 FILE* f = fopen(file_name, "r"); 148 if (!f) { 149 // Assume DSP if /proc/cpuinfo is unavailable. 150 // This will occur for Chrome sandbox for Pepper or Render process. 151 return kCpuHasMIPS_DSP; 152 } 153 while (fgets(cpuinfo_line, sizeof(cpuinfo_line) - 1, f) != NULL) { 154 if (strstr(cpuinfo_line, search_string) != NULL) { 155 fclose(f); 156 return kCpuHasMIPS_DSP; 157 } 158 } 159 fclose(f); 160 return 0; 161 } 162 #endif 163 164 // CPU detect function for SIMD instruction sets. 165 LIBYUV_API 166 int cpu_info_ = kCpuInit; // cpu_info is not initialized yet. 167 168 // Test environment variable for disabling CPU features. Any non-zero value 169 // to disable. Zero ignored to make it easy to set the variable on/off. 170 #if !defined(__native_client__) && !defined(_M_ARM) 171 172 static LIBYUV_BOOL TestEnv(const char* name) { 173 const char* var = getenv(name); 174 if (var) { 175 if (var[0] != '0') { 176 return LIBYUV_TRUE; 177 } 178 } 179 return LIBYUV_FALSE; 180 } 181 #else // nacl does not support getenv(). 182 static LIBYUV_BOOL TestEnv(const char*) { 183 return LIBYUV_FALSE; 184 } 185 #endif 186 187 LIBYUV_API SAFEBUFFERS 188 int InitCpuFlags(void) { 189 #if !defined(__pnacl__) && !defined(__CLR_VER) && defined(CPU_X86) 190 191 uint32 cpu_info1[4] = { 0, 0, 0, 0 }; 192 uint32 cpu_info7[4] = { 0, 0, 0, 0 }; 193 CpuId(1, 0, cpu_info1); 194 CpuId(7, 0, cpu_info7); 195 cpu_info_ = ((cpu_info1[3] & 0x04000000) ? kCpuHasSSE2 : 0) | 196 ((cpu_info1[2] & 0x00000200) ? kCpuHasSSSE3 : 0) | 197 ((cpu_info1[2] & 0x00080000) ? kCpuHasSSE41 : 0) | 198 ((cpu_info1[2] & 0x00100000) ? kCpuHasSSE42 : 0) | 199 ((cpu_info7[1] & 0x00000200) ? kCpuHasERMS : 0) | 200 ((cpu_info1[2] & 0x00001000) ? kCpuHasFMA3 : 0) | 201 kCpuHasX86; 202 #ifdef HAS_XGETBV 203 if ((cpu_info1[2] & 0x18000000) == 0x18000000 && // AVX and OSSave 204 TestOsSaveYmm()) { // Saves YMM. 205 cpu_info_ |= ((cpu_info7[1] & 0x00000020) ? kCpuHasAVX2 : 0) | 206 kCpuHasAVX; 207 } 208 #endif 209 // Environment variable overrides for testing. 210 if (TestEnv("LIBYUV_DISABLE_X86")) { 211 cpu_info_ &= ~kCpuHasX86; 212 } 213 if (TestEnv("LIBYUV_DISABLE_SSE2")) { 214 cpu_info_ &= ~kCpuHasSSE2; 215 } 216 if (TestEnv("LIBYUV_DISABLE_SSSE3")) { 217 cpu_info_ &= ~kCpuHasSSSE3; 218 } 219 if (TestEnv("LIBYUV_DISABLE_SSE41")) { 220 cpu_info_ &= ~kCpuHasSSE41; 221 } 222 if (TestEnv("LIBYUV_DISABLE_SSE42")) { 223 cpu_info_ &= ~kCpuHasSSE42; 224 } 225 if (TestEnv("LIBYUV_DISABLE_AVX")) { 226 cpu_info_ &= ~kCpuHasAVX; 227 } 228 if (TestEnv("LIBYUV_DISABLE_AVX2")) { 229 cpu_info_ &= ~kCpuHasAVX2; 230 } 231 if (TestEnv("LIBYUV_DISABLE_ERMS")) { 232 cpu_info_ &= ~kCpuHasERMS; 233 } 234 if (TestEnv("LIBYUV_DISABLE_FMA3")) { 235 cpu_info_ &= ~kCpuHasFMA3; 236 } 237 #elif defined(__mips__) && defined(__linux__) 238 // Linux mips parse text file for dsp detect. 239 cpu_info_ = MipsCpuCaps("dsp"); // set kCpuHasMIPS_DSP. 240 #if defined(__mips_dspr2) 241 cpu_info_ |= kCpuHasMIPS_DSPR2; 242 #endif 243 cpu_info_ |= kCpuHasMIPS; 244 245 if (getenv("LIBYUV_DISABLE_MIPS")) { 246 cpu_info_ &= ~kCpuHasMIPS; 247 } 248 if (getenv("LIBYUV_DISABLE_MIPS_DSP")) { 249 cpu_info_ &= ~kCpuHasMIPS_DSP; 250 } 251 if (getenv("LIBYUV_DISABLE_MIPS_DSPR2")) { 252 cpu_info_ &= ~kCpuHasMIPS_DSPR2; 253 } 254 #elif defined(__arm__) 255 // gcc -mfpu=neon defines __ARM_NEON__ 256 // __ARM_NEON__ generates code that requires Neon. NaCL also requires Neon. 257 // For Linux, /proc/cpuinfo can be tested but without that assume Neon. 258 #if defined(__ARM_NEON__) || defined(__native_client__) || !defined(__linux__) 259 cpu_info_ = kCpuHasNEON; 260 #else 261 // Linux arm parse text file for neon detect. 262 cpu_info_ = ArmCpuCaps("/proc/cpuinfo"); 263 #endif 264 cpu_info_ |= kCpuHasARM; 265 if (TestEnv("LIBYUV_DISABLE_NEON")) { 266 cpu_info_ &= ~kCpuHasNEON; 267 } 268 #endif // __arm__ 269 if (TestEnv("LIBYUV_DISABLE_ASM")) { 270 cpu_info_ = 0; 271 } 272 return cpu_info_; 273 } 274 275 LIBYUV_API 276 void MaskCpuFlags(int enable_flags) { 277 cpu_info_ = InitCpuFlags() & enable_flags; 278 } 279 280 #ifdef __cplusplus 281 } // extern "C" 282 } // namespace libyuv 283 #endif 284
