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 #if (defined(_MSC_VER) && !defined(__clang__)) && !defined(__clang__) 14 #include <intrin.h> // For __cpuidex() 15 #endif 16 #if !defined(__pnacl__) && !defined(__CLR_VER) && \ 17 !defined(__native_client__) && (defined(_M_IX86) || defined(_M_X64)) && \ 18 defined(_MSC_VER) && !defined(__clang__) && (_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) && !defined(__clang__)) && (_MSC_FULL_VER >= 160040219) 40 #define SAFEBUFFERS __declspec(safebuffers) 41 #else 42 #define SAFEBUFFERS 43 #endif 44 45 // Low level cpuid for X86. 46 #if (defined(_M_IX86) || defined(_M_X64) || \ 47 defined(__i386__) || defined(__x86_64__)) && \ 48 !defined(__pnacl__) && !defined(__CLR_VER) 49 LIBYUV_API 50 void CpuId(uint32 info_eax, uint32 info_ecx, uint32* cpu_info) { 51 #if (defined(_MSC_VER) && !defined(__clang__)) && !defined(__clang__) 52 // Visual C version uses intrinsic or inline x86 assembly. 53 #if (_MSC_FULL_VER >= 160040219) 54 __cpuidex((int*)(cpu_info), info_eax, info_ecx); 55 #elif defined(_M_IX86) 56 __asm { 57 mov eax, info_eax 58 mov ecx, info_ecx 59 mov edi, cpu_info 60 cpuid 61 mov [edi], eax 62 mov [edi + 4], ebx 63 mov [edi + 8], ecx 64 mov [edi + 12], edx 65 } 66 #else 67 if (info_ecx == 0) { 68 __cpuid((int*)(cpu_info), info_eax); 69 } else { 70 cpu_info[3] = cpu_info[2] = cpu_info[1] = cpu_info[0] = 0; 71 } 72 #endif 73 // GCC version uses inline x86 assembly. 74 #else // (defined(_MSC_VER) && !defined(__clang__)) && !defined(__clang__) 75 uint32 info_ebx, info_edx; 76 asm volatile ( // NOLINT 77 #if defined( __i386__) && defined(__PIC__) 78 // Preserve ebx for fpic 32 bit. 79 "mov %%ebx, %%edi \n" 80 "cpuid \n" 81 "xchg %%edi, %%ebx \n" 82 : "=D" (info_ebx), 83 #else 84 "cpuid \n" 85 : "=b" (info_ebx), 86 #endif // defined( __i386__) && defined(__PIC__) 87 "+a" (info_eax), "+c" (info_ecx), "=d" (info_edx)); 88 cpu_info[0] = info_eax; 89 cpu_info[1] = info_ebx; 90 cpu_info[2] = info_ecx; 91 cpu_info[3] = info_edx; 92 #endif // (defined(_MSC_VER) && !defined(__clang__)) && !defined(__clang__) 93 } 94 #else // (defined(_M_IX86) || defined(_M_X64) ... 95 LIBYUV_API 96 void CpuId(uint32 eax, uint32 ecx, uint32* cpu_info) { 97 cpu_info[0] = cpu_info[1] = cpu_info[2] = cpu_info[3] = 0; 98 } 99 #endif 100 101 // TODO(fbarchard): Enable xgetbv when validator supports it. 102 #if (defined(_M_IX86) || defined(_M_X64) || \ 103 defined(__i386__) || defined(__x86_64__)) && \ 104 !defined(__pnacl__) && !defined(__CLR_VER) && !defined(__native_client__) 105 #define HAS_XGETBV 106 // X86 CPUs have xgetbv to detect OS saves high parts of ymm registers. 107 int TestOsSaveYmm() { 108 uint32 xcr0 = 0u; 109 #if (defined(_MSC_VER) && !defined(__clang__)) && (_MSC_FULL_VER >= 160040219) 110 xcr0 = (uint32)(_xgetbv(0)); // VS2010 SP1 required. 111 #elif defined(_M_IX86) && defined(_MSC_VER) && !defined(__clang__) 112 __asm { 113 xor ecx, ecx // xcr 0 114 _asm _emit 0x0f _asm _emit 0x01 _asm _emit 0xd0 // For VS2010 and earlier. 115 mov xcr0, eax 116 } 117 #elif defined(__i386__) || defined(__x86_64__) 118 asm(".byte 0x0f, 0x01, 0xd0" : "=a" (xcr0) : "c" (0) : "%edx"); 119 #endif // defined(__i386__) || defined(__x86_64__) 120 return((xcr0 & 6) == 6); // Is ymm saved? 121 } 122 #endif // defined(_M_IX86) || defined(_M_X64) .. 123 124 // based on libvpx arm_cpudetect.c 125 // For Arm, but public to allow testing on any CPU 126 LIBYUV_API SAFEBUFFERS 127 int ArmCpuCaps(const char* cpuinfo_name) { 128 char cpuinfo_line[512]; 129 FILE* f = fopen(cpuinfo_name, "r"); 130 if (!f) { 131 // Assume Neon if /proc/cpuinfo is unavailable. 132 // This will occur for Chrome sandbox for Pepper or Render process. 133 return kCpuHasNEON; 134 } 135 while (fgets(cpuinfo_line, sizeof(cpuinfo_line) - 1, f)) { 136 if (memcmp(cpuinfo_line, "Features", 8) == 0) { 137 char* p = strstr(cpuinfo_line, " neon"); 138 if (p && (p[5] == ' ' || p[5] == '\n')) { 139 fclose(f); 140 return kCpuHasNEON; 141 } 142 // aarch64 uses asimd for Neon. 143 p = strstr(cpuinfo_line, " asimd"); 144 if (p && (p[6] == ' ' || p[6] == '\n')) { 145 fclose(f); 146 return kCpuHasNEON; 147 } 148 } 149 } 150 fclose(f); 151 return 0; 152 } 153 154 #if defined(__mips__) && defined(__linux__) 155 static int MipsCpuCaps(const char* search_string) { 156 char cpuinfo_line[512]; 157 const char* file_name = "/proc/cpuinfo"; 158 FILE* f = fopen(file_name, "r"); 159 if (!f) { 160 // Assume DSP if /proc/cpuinfo is unavailable. 161 // This will occur for Chrome sandbox for Pepper or Render process. 162 return kCpuHasMIPS_DSP; 163 } 164 while (fgets(cpuinfo_line, sizeof(cpuinfo_line) - 1, f) != NULL) { 165 if (strstr(cpuinfo_line, search_string) != NULL) { 166 fclose(f); 167 return kCpuHasMIPS_DSP; 168 } 169 } 170 fclose(f); 171 return 0; 172 } 173 #endif 174 175 // CPU detect function for SIMD instruction sets. 176 LIBYUV_API 177 int cpu_info_ = kCpuInit; // cpu_info is not initialized yet. 178 179 // Test environment variable for disabling CPU features. Any non-zero value 180 // to disable. Zero ignored to make it easy to set the variable on/off. 181 #if !defined(__native_client__) && !defined(_M_ARM) 182 183 static LIBYUV_BOOL TestEnv(const char* name) { 184 const char* var = getenv(name); 185 if (var) { 186 if (var[0] != '0') { 187 return LIBYUV_TRUE; 188 } 189 } 190 return LIBYUV_FALSE; 191 } 192 #else // nacl does not support getenv(). 193 static LIBYUV_BOOL TestEnv(const char*) { 194 return LIBYUV_FALSE; 195 } 196 #endif 197 198 LIBYUV_API SAFEBUFFERS 199 int InitCpuFlags(void) { 200 #if !defined(__pnacl__) && !defined(__CLR_VER) && defined(CPU_X86) 201 202 uint32 cpu_info0[4] = { 0, 0, 0, 0 }; 203 uint32 cpu_info1[4] = { 0, 0, 0, 0 }; 204 uint32 cpu_info7[4] = { 0, 0, 0, 0 }; 205 CpuId(0, 0, cpu_info0); 206 CpuId(1, 0, cpu_info1); 207 if (cpu_info0[0] >= 7) { 208 CpuId(7, 0, cpu_info7); 209 } 210 cpu_info_ = ((cpu_info1[3] & 0x04000000) ? kCpuHasSSE2 : 0) | 211 ((cpu_info1[2] & 0x00000200) ? kCpuHasSSSE3 : 0) | 212 ((cpu_info1[2] & 0x00080000) ? kCpuHasSSE41 : 0) | 213 ((cpu_info1[2] & 0x00100000) ? kCpuHasSSE42 : 0) | 214 ((cpu_info7[1] & 0x00000200) ? kCpuHasERMS : 0) | 215 ((cpu_info1[2] & 0x00001000) ? kCpuHasFMA3 : 0) | 216 kCpuHasX86; 217 218 #ifdef HAS_XGETBV 219 if ((cpu_info1[2] & 0x18000000) == 0x18000000 && // AVX and OSSave 220 TestOsSaveYmm()) { // Saves YMM. 221 cpu_info_ |= ((cpu_info7[1] & 0x00000020) ? kCpuHasAVX2 : 0) | 222 kCpuHasAVX; 223 } 224 #endif 225 // Environment variable overrides for testing. 226 if (TestEnv("LIBYUV_DISABLE_X86")) { 227 cpu_info_ &= ~kCpuHasX86; 228 } 229 if (TestEnv("LIBYUV_DISABLE_SSE2")) { 230 cpu_info_ &= ~kCpuHasSSE2; 231 } 232 if (TestEnv("LIBYUV_DISABLE_SSSE3")) { 233 cpu_info_ &= ~kCpuHasSSSE3; 234 } 235 if (TestEnv("LIBYUV_DISABLE_SSE41")) { 236 cpu_info_ &= ~kCpuHasSSE41; 237 } 238 if (TestEnv("LIBYUV_DISABLE_SSE42")) { 239 cpu_info_ &= ~kCpuHasSSE42; 240 } 241 if (TestEnv("LIBYUV_DISABLE_AVX")) { 242 cpu_info_ &= ~kCpuHasAVX; 243 } 244 if (TestEnv("LIBYUV_DISABLE_AVX2")) { 245 cpu_info_ &= ~kCpuHasAVX2; 246 } 247 if (TestEnv("LIBYUV_DISABLE_ERMS")) { 248 cpu_info_ &= ~kCpuHasERMS; 249 } 250 if (TestEnv("LIBYUV_DISABLE_FMA3")) { 251 cpu_info_ &= ~kCpuHasFMA3; 252 } 253 #endif 254 #if defined(__mips__) && defined(__linux__) 255 // Linux mips parse text file for dsp detect. 256 cpu_info_ = MipsCpuCaps("dsp"); // set kCpuHasMIPS_DSP. 257 #if defined(__mips_dspr2) 258 cpu_info_ |= kCpuHasMIPS_DSPR2; 259 #endif 260 cpu_info_ |= kCpuHasMIPS; 261 262 if (getenv("LIBYUV_DISABLE_MIPS")) { 263 cpu_info_ &= ~kCpuHasMIPS; 264 } 265 if (getenv("LIBYUV_DISABLE_MIPS_DSP")) { 266 cpu_info_ &= ~kCpuHasMIPS_DSP; 267 } 268 if (getenv("LIBYUV_DISABLE_MIPS_DSPR2")) { 269 cpu_info_ &= ~kCpuHasMIPS_DSPR2; 270 } 271 #endif 272 #if defined(__arm__) || defined(__aarch64__) 273 // gcc -mfpu=neon defines __ARM_NEON__ 274 // __ARM_NEON__ generates code that requires Neon. NaCL also requires Neon. 275 // For Linux, /proc/cpuinfo can be tested but without that assume Neon. 276 #if defined(__ARM_NEON__) || defined(__native_client__) || !defined(__linux__) 277 cpu_info_ = kCpuHasNEON; 278 // For aarch64(arm64), /proc/cpuinfo's feature is not complete, e.g. no neon 279 // flag in it. 280 // So for aarch64, neon enabling is hard coded here. 281 #endif 282 #if defined(__aarch64__) 283 cpu_info_ = kCpuHasNEON; 284 #else 285 // Linux arm parse text file for neon detect. 286 cpu_info_ = ArmCpuCaps("/proc/cpuinfo"); 287 #endif 288 cpu_info_ |= kCpuHasARM; 289 if (TestEnv("LIBYUV_DISABLE_NEON")) { 290 cpu_info_ &= ~kCpuHasNEON; 291 } 292 #endif // __arm__ 293 if (TestEnv("LIBYUV_DISABLE_ASM")) { 294 cpu_info_ = 0; 295 } 296 return cpu_info_; 297 } 298 299 LIBYUV_API 300 void MaskCpuFlags(int enable_flags) { 301 cpu_info_ = InitCpuFlags() & enable_flags; 302 } 303 304 #ifdef __cplusplus 305 } // extern "C" 306 } // namespace libyuv 307 #endif 308