1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libyuv/source/cpu_id.cc Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,279 @@
1.4 +/*
1.5 + * Copyright 2011 The LibYuv Project Authors. All rights reserved.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license
1.8 + * that can be found in the LICENSE file in the root of the source
1.9 + * tree. An additional intellectual property rights grant can be found
1.10 + * in the file PATENTS. All contributing project authors may
1.11 + * be found in the AUTHORS file in the root of the source tree.
1.12 + */
1.13 +
1.14 +#include "libyuv/cpu_id.h"
1.15 +
1.16 +#ifdef _MSC_VER
1.17 +#include <intrin.h> // For __cpuidex()
1.18 +#endif
1.19 +#if !defined(__pnacl__) && !defined(__CLR_VER) && \
1.20 + !defined(__native_client__) && defined(_M_X64) && \
1.21 + defined(_MSC_VER) && (_MSC_FULL_VER >= 160040219)
1.22 +#include <immintrin.h> // For _xgetbv()
1.23 +#endif
1.24 +
1.25 +#if !defined(__native_client__)
1.26 +#include <stdlib.h> // For getenv()
1.27 +#endif
1.28 +
1.29 +// For ArmCpuCaps() but unittested on all platforms
1.30 +#include <stdio.h>
1.31 +#include <string.h>
1.32 +
1.33 +#include "libyuv/basic_types.h" // For CPU_X86
1.34 +
1.35 +#ifdef __cplusplus
1.36 +namespace libyuv {
1.37 +extern "C" {
1.38 +#endif
1.39 +
1.40 +// For functions that use the stack and have runtime checks for overflow,
1.41 +// use SAFEBUFFERS to avoid additional check.
1.42 +#if defined(_MSC_VER) && (_MSC_FULL_VER >= 160040219)
1.43 +#define SAFEBUFFERS __declspec(safebuffers)
1.44 +#else
1.45 +#define SAFEBUFFERS
1.46 +#endif
1.47 +
1.48 +// Low level cpuid for X86. Returns zeros on other CPUs.
1.49 +#if !defined(__pnacl__) && !defined(__CLR_VER) && \
1.50 + (defined(_M_IX86) || defined(_M_X64) || \
1.51 + defined(__i386__) || defined(__x86_64__))
1.52 +LIBYUV_API
1.53 +void CpuId(uint32 info_eax, uint32 info_ecx, uint32* cpu_info) {
1.54 +#if defined(_MSC_VER)
1.55 +#if (_MSC_FULL_VER >= 160040219)
1.56 + __cpuidex((int*)(cpu_info), info_eax, info_ecx);
1.57 +#elif defined(_M_IX86)
1.58 + __asm {
1.59 + mov eax, info_eax
1.60 + mov ecx, info_ecx
1.61 + mov edi, cpu_info
1.62 + cpuid
1.63 + mov [edi], eax
1.64 + mov [edi + 4], ebx
1.65 + mov [edi + 8], ecx
1.66 + mov [edi + 12], edx
1.67 + }
1.68 +#else
1.69 + if (info_ecx == 0) {
1.70 + __cpuid((int*)(cpu_info), info_eax);
1.71 + } else {
1.72 + cpu_info[3] = cpu_info[2] = cpu_info[1] = cpu_info[0] = 0;
1.73 + }
1.74 +#endif
1.75 +#else // defined(_MSC_VER)
1.76 + uint32 info_ebx, info_edx;
1.77 + asm volatile ( // NOLINT
1.78 +#if defined( __i386__) && defined(__PIC__)
1.79 + // Preserve ebx for fpic 32 bit.
1.80 + "mov %%ebx, %%edi \n"
1.81 + "cpuid \n"
1.82 + "xchg %%edi, %%ebx \n"
1.83 + : "=D" (info_ebx),
1.84 +#else
1.85 + "cpuid \n"
1.86 + : "=b" (info_ebx),
1.87 +#endif // defined( __i386__) && defined(__PIC__)
1.88 + "+a" (info_eax), "+c" (info_ecx), "=d" (info_edx));
1.89 + cpu_info[0] = info_eax;
1.90 + cpu_info[1] = info_ebx;
1.91 + cpu_info[2] = info_ecx;
1.92 + cpu_info[3] = info_edx;
1.93 +#endif // defined(_MSC_VER)
1.94 +}
1.95 +
1.96 +#if !defined(__native_client__)
1.97 +#define HAS_XGETBV
1.98 +// X86 CPUs have xgetbv to detect OS saves high parts of ymm registers.
1.99 +int TestOsSaveYmm() {
1.100 + uint32 xcr0 = 0u;
1.101 +#if defined(_MSC_VER) && defined(_XCR_XFEATURE_ENABLED_MASK)
1.102 + xcr0 = (uint32)(_xgetbv(_XCR_XFEATURE_ENABLED_MASK));
1.103 +#elif defined(_MSC_VER) && defined(_M_IX86)
1.104 + __asm {
1.105 + xor ecx, ecx // xcr 0
1.106 + _asm _emit 0x0f _asm _emit 0x01 _asm _emit 0xd0 // For VS2010 and earlier.
1.107 + mov xcr0, eax
1.108 + }
1.109 +#elif defined(__i386__) || defined(__x86_64__)
1.110 + asm(".byte 0x0f, 0x01, 0xd0" : "=a" (xcr0) : "c" (0) : "%edx");
1.111 +#endif // defined(_MSC_VER)
1.112 + return((xcr0 & 6) == 6); // Is ymm saved?
1.113 +}
1.114 +#endif // !defined(__native_client__)
1.115 +#else
1.116 +LIBYUV_API
1.117 +void CpuId(uint32 eax, uint32 ecx, uint32* cpu_info) {
1.118 + cpu_info[0] = cpu_info[1] = cpu_info[2] = cpu_info[3] = 0;
1.119 +}
1.120 +#endif
1.121 +
1.122 +// based on libvpx arm_cpudetect.c
1.123 +// For Arm, but public to allow testing on any CPU
1.124 +LIBYUV_API SAFEBUFFERS
1.125 +int ArmCpuCaps(const char* cpuinfo_name) {
1.126 + FILE* f = fopen(cpuinfo_name, "r");
1.127 + if (f) {
1.128 + char cpuinfo_line[512];
1.129 + while (fgets(cpuinfo_line, sizeof(cpuinfo_line) - 1, f)) {
1.130 + if (memcmp(cpuinfo_line, "Features", 8) == 0) {
1.131 + char* p = strstr(cpuinfo_line, " neon");
1.132 + if (p && (p[5] == ' ' || p[5] == '\n')) {
1.133 + fclose(f);
1.134 + return kCpuHasNEON;
1.135 + }
1.136 + }
1.137 + }
1.138 + fclose(f);
1.139 + }
1.140 + return 0;
1.141 +}
1.142 +
1.143 +#if defined(__mips__) && defined(__linux__)
1.144 +static int MipsCpuCaps(const char* search_string) {
1.145 + const char* file_name = "/proc/cpuinfo";
1.146 + char cpuinfo_line[256];
1.147 + FILE* f = NULL;
1.148 + if ((f = fopen(file_name, "r")) != NULL) {
1.149 + while (fgets(cpuinfo_line, sizeof(cpuinfo_line) - 1, f) != NULL) {
1.150 + if (strstr(cpuinfo_line, search_string) != NULL) {
1.151 + fclose(f);
1.152 + return kCpuHasMIPS_DSP;
1.153 + }
1.154 + }
1.155 + fclose(f);
1.156 + }
1.157 + /* Did not find string in the proc file, or not Linux ELF. */
1.158 + return 0;
1.159 +}
1.160 +#endif
1.161 +
1.162 +// CPU detect function for SIMD instruction sets.
1.163 +LIBYUV_API
1.164 +int cpu_info_ = kCpuInit; // cpu_info is not initialized yet.
1.165 +
1.166 +// Test environment variable for disabling CPU features. Any non-zero value
1.167 +// to disable. Zero ignored to make it easy to set the variable on/off.
1.168 +#if !defined(__native_client__) && !defined(_M_ARM)
1.169 +
1.170 +static LIBYUV_BOOL TestEnv(const char* name) {
1.171 + const char* var = getenv(name);
1.172 + if (var) {
1.173 + if (var[0] != '0') {
1.174 + return LIBYUV_TRUE;
1.175 + }
1.176 + }
1.177 + return LIBYUV_FALSE;
1.178 +}
1.179 +#else // nacl does not support getenv().
1.180 +static LIBYUV_BOOL TestEnv(const char*) {
1.181 + return LIBYUV_FALSE;
1.182 +}
1.183 +#endif
1.184 +
1.185 +LIBYUV_API SAFEBUFFERS
1.186 +int InitCpuFlags(void) {
1.187 +#if !defined(__pnacl__) && !defined(__CLR_VER) && defined(CPU_X86)
1.188 +
1.189 + uint32 cpu_info1[4] = { 0, 0, 0, 0 };
1.190 + uint32 cpu_info7[4] = { 0, 0, 0, 0 };
1.191 + CpuId(1, 0, cpu_info1);
1.192 + CpuId(7, 0, cpu_info7);
1.193 + cpu_info_ = ((cpu_info1[3] & 0x04000000) ? kCpuHasSSE2 : 0) |
1.194 + ((cpu_info1[2] & 0x00000200) ? kCpuHasSSSE3 : 0) |
1.195 + ((cpu_info1[2] & 0x00080000) ? kCpuHasSSE41 : 0) |
1.196 + ((cpu_info1[2] & 0x00100000) ? kCpuHasSSE42 : 0) |
1.197 + ((cpu_info7[1] & 0x00000200) ? kCpuHasERMS : 0) |
1.198 + ((cpu_info1[2] & 0x00001000) ? kCpuHasFMA3 : 0) |
1.199 + kCpuHasX86;
1.200 +#ifdef HAS_XGETBV
1.201 + if ((cpu_info1[2] & 0x18000000) == 0x18000000 && // AVX and OSSave
1.202 + TestOsSaveYmm()) { // Saves YMM.
1.203 + cpu_info_ |= ((cpu_info7[1] & 0x00000020) ? kCpuHasAVX2 : 0) |
1.204 + kCpuHasAVX;
1.205 + }
1.206 +#endif
1.207 + // Environment variable overrides for testing.
1.208 + if (TestEnv("LIBYUV_DISABLE_X86")) {
1.209 + cpu_info_ &= ~kCpuHasX86;
1.210 + }
1.211 + if (TestEnv("LIBYUV_DISABLE_SSE2")) {
1.212 + cpu_info_ &= ~kCpuHasSSE2;
1.213 + }
1.214 + if (TestEnv("LIBYUV_DISABLE_SSSE3")) {
1.215 + cpu_info_ &= ~kCpuHasSSSE3;
1.216 + }
1.217 + if (TestEnv("LIBYUV_DISABLE_SSE41")) {
1.218 + cpu_info_ &= ~kCpuHasSSE41;
1.219 + }
1.220 + if (TestEnv("LIBYUV_DISABLE_SSE42")) {
1.221 + cpu_info_ &= ~kCpuHasSSE42;
1.222 + }
1.223 + if (TestEnv("LIBYUV_DISABLE_AVX")) {
1.224 + cpu_info_ &= ~kCpuHasAVX;
1.225 + }
1.226 + if (TestEnv("LIBYUV_DISABLE_AVX2")) {
1.227 + cpu_info_ &= ~kCpuHasAVX2;
1.228 + }
1.229 + if (TestEnv("LIBYUV_DISABLE_ERMS")) {
1.230 + cpu_info_ &= ~kCpuHasERMS;
1.231 + }
1.232 + if (TestEnv("LIBYUV_DISABLE_FMA3")) {
1.233 + cpu_info_ &= ~kCpuHasFMA3;
1.234 + }
1.235 +#elif defined(__mips__) && defined(__linux__)
1.236 + // Linux mips parse text file for dsp detect.
1.237 + cpu_info_ = MipsCpuCaps("dsp"); // set kCpuHasMIPS_DSP.
1.238 +#if defined(__mips_dspr2)
1.239 + cpu_info_ |= kCpuHasMIPS_DSPR2;
1.240 +#endif
1.241 + cpu_info_ |= kCpuHasMIPS;
1.242 +
1.243 + if (getenv("LIBYUV_DISABLE_MIPS")) {
1.244 + cpu_info_ &= ~kCpuHasMIPS;
1.245 + }
1.246 + if (getenv("LIBYUV_DISABLE_MIPS_DSP")) {
1.247 + cpu_info_ &= ~kCpuHasMIPS_DSP;
1.248 + }
1.249 + if (getenv("LIBYUV_DISABLE_MIPS_DSPR2")) {
1.250 + cpu_info_ &= ~kCpuHasMIPS_DSPR2;
1.251 + }
1.252 +#elif defined(__arm__)
1.253 +#if defined(__linux__) && (defined(__ARM_NEON__) || defined(LIBYUV_NEON)) && \
1.254 + !defined(__native_client__)
1.255 + // Linux arm parse text file for neon detect.
1.256 + cpu_info_ = ArmCpuCaps("/proc/cpuinfo");
1.257 +#elif defined(__ARM_NEON__) || defined(__native_client__)
1.258 + // gcc -mfpu=neon defines __ARM_NEON__
1.259 + // Enable Neon if you want support for Neon and Arm, and use MaskCpuFlags
1.260 + // to disable Neon on devices that do not have it.
1.261 + cpu_info_ = kCpuHasNEON;
1.262 +#endif
1.263 + cpu_info_ |= kCpuHasARM;
1.264 + if (TestEnv("LIBYUV_DISABLE_NEON")) {
1.265 + cpu_info_ &= ~kCpuHasNEON;
1.266 + }
1.267 +#endif // __arm__
1.268 + if (TestEnv("LIBYUV_DISABLE_ASM")) {
1.269 + cpu_info_ = 0;
1.270 + }
1.271 + return cpu_info_;
1.272 +}
1.273 +
1.274 +LIBYUV_API
1.275 +void MaskCpuFlags(int enable_flags) {
1.276 + cpu_info_ = InitCpuFlags() & enable_flags;
1.277 +}
1.278 +
1.279 +#ifdef __cplusplus
1.280 +} // extern "C"
1.281 +} // namespace libyuv
1.282 +#endif
