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Diffstat (limited to 'third_party/yuv/source/cpu_id.cc')
| -rw-r--r-- | third_party/yuv/source/cpu_id.cc | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/third_party/yuv/source/cpu_id.cc b/third_party/yuv/source/cpu_id.cc new file mode 100644 index 00000000..84927ebc --- /dev/null +++ b/third_party/yuv/source/cpu_id.cc @@ -0,0 +1,300 @@ +/* + * Copyright 2011 The LibYuv Project Authors. All rights reserved. + * + * Use of this source code is governed by a BSD-style license + * that can be found in the LICENSE file in the root of the source + * tree. An additional intellectual property rights grant can be found + * in the file PATENTS. All contributing project authors may + * be found in the AUTHORS file in the root of the source tree. + */ + +#include "libyuv/cpu_id.h" + +#if defined(_MSC_VER) +#include <intrin.h> // For __cpuidex() +#endif +#if !defined(__pnacl__) && !defined(__CLR_VER) && \ + !defined(__native_client__) && (defined(_M_IX86) || defined(_M_X64)) && \ + defined(_MSC_FULL_VER) && (_MSC_FULL_VER >= 160040219) +#include <immintrin.h> // For _xgetbv() +#endif + +#if !defined(__native_client__) +#include <stdlib.h> // For getenv() +#endif + +// For ArmCpuCaps() but unittested on all platforms +#include <stdio.h> +#include <string.h> + +#include "libyuv/basic_types.h" // For CPU_X86 + +#ifdef __cplusplus +namespace libyuv { +extern "C" { +#endif + +// For functions that use the stack and have runtime checks for overflow, +// use SAFEBUFFERS to avoid additional check. +#if defined(_MSC_FULL_VER) && (_MSC_FULL_VER >= 160040219) && \ + !defined(__clang__) +#define SAFEBUFFERS __declspec(safebuffers) +#else +#define SAFEBUFFERS +#endif + +// Low level cpuid for X86. +#if (defined(_M_IX86) || defined(_M_X64) || \ + defined(__i386__) || defined(__x86_64__)) && \ + !defined(__pnacl__) && !defined(__CLR_VER) +LIBYUV_API +void CpuId(uint32 info_eax, uint32 info_ecx, uint32* cpu_info) { +#if defined(_MSC_VER) +// Visual C version uses intrinsic or inline x86 assembly. +#if defined(_MSC_FULL_VER) && (_MSC_FULL_VER >= 160040219) + __cpuidex((int*)(cpu_info), info_eax, info_ecx); +#elif defined(_M_IX86) + __asm { + mov eax, info_eax + mov ecx, info_ecx + mov edi, cpu_info + cpuid + mov [edi], eax + mov [edi + 4], ebx + mov [edi + 8], ecx + mov [edi + 12], edx + } +#else // Visual C but not x86 + if (info_ecx == 0) { + __cpuid((int*)(cpu_info), info_eax); + } else { + cpu_info[3] = cpu_info[2] = cpu_info[1] = cpu_info[0] = 0; + } +#endif +// GCC version uses inline x86 assembly. +#else // defined(_MSC_VER) + uint32 info_ebx, info_edx; + asm volatile ( +#if defined( __i386__) && defined(__PIC__) + // Preserve ebx for fpic 32 bit. + "mov %%ebx, %%edi \n" + "cpuid \n" + "xchg %%edi, %%ebx \n" + : "=D" (info_ebx), +#else + "cpuid \n" + : "=b" (info_ebx), +#endif // defined( __i386__) && defined(__PIC__) + "+a" (info_eax), "+c" (info_ecx), "=d" (info_edx)); + cpu_info[0] = info_eax; + cpu_info[1] = info_ebx; + cpu_info[2] = info_ecx; + cpu_info[3] = info_edx; +#endif // defined(_MSC_VER) +} +#else // (defined(_M_IX86) || defined(_M_X64) ... +LIBYUV_API +void CpuId(uint32 eax, uint32 ecx, uint32* cpu_info) { + cpu_info[0] = cpu_info[1] = cpu_info[2] = cpu_info[3] = 0; +} +#endif + +// For VS2010 and earlier emit can be used: +// _asm _emit 0x0f _asm _emit 0x01 _asm _emit 0xd0 // For VS2010 and earlier. +// __asm { +// xor ecx, ecx // xcr 0 +// xgetbv +// mov xcr0, eax +// } +// For VS2013 and earlier 32 bit, the _xgetbv(0) optimizer produces bad code. +// https://code.google.com/p/libyuv/issues/detail?id=529 +#if defined(_M_IX86) && (_MSC_VER < 1900) +#pragma optimize("g", off) +#endif +#if (defined(_M_IX86) || defined(_M_X64) || \ + defined(__i386__) || defined(__x86_64__)) && \ + !defined(__pnacl__) && !defined(__CLR_VER) && !defined(__native_client__) +#define HAS_XGETBV +// X86 CPUs have xgetbv to detect OS saves high parts of ymm registers. +int GetXCR0() { + uint32 xcr0 = 0u; +#if defined(_MSC_FULL_VER) && (_MSC_FULL_VER >= 160040219) + xcr0 = (uint32)(_xgetbv(0)); // VS2010 SP1 required. +#elif defined(__i386__) || defined(__x86_64__) + asm(".byte 0x0f, 0x01, 0xd0" : "=a" (xcr0) : "c" (0) : "%edx"); +#endif // defined(__i386__) || defined(__x86_64__) + return xcr0; +} +#endif // defined(_M_IX86) || defined(_M_X64) .. +// Return optimization to previous setting. +#if defined(_M_IX86) && (_MSC_VER < 1900) +#pragma optimize("g", on) +#endif + +// based on libvpx arm_cpudetect.c +// For Arm, but public to allow testing on any CPU +LIBYUV_API SAFEBUFFERS +int ArmCpuCaps(const char* cpuinfo_name) { + char cpuinfo_line[512]; + FILE* f = fopen(cpuinfo_name, "r"); + if (!f) { + // Assume Neon if /proc/cpuinfo is unavailable. + // This will occur for Chrome sandbox for Pepper or Render process. + return kCpuHasNEON; + } + while (fgets(cpuinfo_line, sizeof(cpuinfo_line) - 1, f)) { + if (memcmp(cpuinfo_line, "Features", 8) == 0) { + char* p = strstr(cpuinfo_line, " neon"); + if (p && (p[5] == ' ' || p[5] == '\n')) { + fclose(f); + return kCpuHasNEON; + } + // aarch64 uses asimd for Neon. + p = strstr(cpuinfo_line, " asimd"); + if (p && (p[6] == ' ' || p[6] == '\n')) { + fclose(f); + return kCpuHasNEON; + } + } + } + fclose(f); + return 0; +} + +// CPU detect function for SIMD instruction sets. +LIBYUV_API +int cpu_info_ = 0; // cpu_info is not initialized yet. + +// Test environment variable for disabling CPU features. Any non-zero value +// to disable. Zero ignored to make it easy to set the variable on/off. +#if !defined(__native_client__) && !defined(_M_ARM) + +static LIBYUV_BOOL TestEnv(const char* name) { + const char* var = getenv(name); + if (var) { + if (var[0] != '0') { + return LIBYUV_TRUE; + } + } + return LIBYUV_FALSE; +} +#else // nacl does not support getenv(). +static LIBYUV_BOOL TestEnv(const char*) { + return LIBYUV_FALSE; +} +#endif + +LIBYUV_API SAFEBUFFERS +int InitCpuFlags(void) { + // TODO(fbarchard): swap kCpuInit logic so 0 means uninitialized. + int cpu_info = 0; +#if !defined(__pnacl__) && !defined(__CLR_VER) && defined(CPU_X86) + uint32 cpu_info0[4] = { 0, 0, 0, 0 }; + uint32 cpu_info1[4] = { 0, 0, 0, 0 }; + uint32 cpu_info7[4] = { 0, 0, 0, 0 }; + CpuId(0, 0, cpu_info0); + CpuId(1, 0, cpu_info1); + if (cpu_info0[0] >= 7) { + CpuId(7, 0, cpu_info7); + } + cpu_info = ((cpu_info1[3] & 0x04000000) ? kCpuHasSSE2 : 0) | + ((cpu_info1[2] & 0x00000200) ? kCpuHasSSSE3 : 0) | + ((cpu_info1[2] & 0x00080000) ? kCpuHasSSE41 : 0) | + ((cpu_info1[2] & 0x00100000) ? kCpuHasSSE42 : 0) | + ((cpu_info7[1] & 0x00000200) ? kCpuHasERMS : 0) | + ((cpu_info1[2] & 0x00001000) ? kCpuHasFMA3 : 0) | + kCpuHasX86; + +#ifdef HAS_XGETBV + // AVX requires CPU has AVX, XSAVE and OSXSave for xgetbv + if (((cpu_info1[2] & 0x1c000000) == 0x1c000000) && // AVX and OSXSave + ((GetXCR0() & 6) == 6)) { // Test OS saves YMM registers + cpu_info |= ((cpu_info7[1] & 0x00000020) ? kCpuHasAVX2 : 0) | kCpuHasAVX; + + // Detect AVX512bw + if ((GetXCR0() & 0xe0) == 0xe0) { + cpu_info |= (cpu_info7[1] & 0x40000000) ? kCpuHasAVX3 : 0; + } + } +#endif + + // Environment variable overrides for testing. + if (TestEnv("LIBYUV_DISABLE_X86")) { + cpu_info &= ~kCpuHasX86; + } + if (TestEnv("LIBYUV_DISABLE_SSE2")) { + cpu_info &= ~kCpuHasSSE2; + } + if (TestEnv("LIBYUV_DISABLE_SSSE3")) { + cpu_info &= ~kCpuHasSSSE3; + } + if (TestEnv("LIBYUV_DISABLE_SSE41")) { + cpu_info &= ~kCpuHasSSE41; + } + if (TestEnv("LIBYUV_DISABLE_SSE42")) { + cpu_info &= ~kCpuHasSSE42; + } + if (TestEnv("LIBYUV_DISABLE_AVX")) { + cpu_info &= ~kCpuHasAVX; + } + if (TestEnv("LIBYUV_DISABLE_AVX2")) { + cpu_info &= ~kCpuHasAVX2; + } + if (TestEnv("LIBYUV_DISABLE_ERMS")) { + cpu_info &= ~kCpuHasERMS; + } + if (TestEnv("LIBYUV_DISABLE_FMA3")) { + cpu_info &= ~kCpuHasFMA3; + } + if (TestEnv("LIBYUV_DISABLE_AVX3")) { + cpu_info &= ~kCpuHasAVX3; + } +#endif +#if defined(__mips__) && defined(__linux__) +#if defined(__mips_dspr2) + cpu_info |= kCpuHasDSPR2; +#endif + cpu_info |= kCpuHasMIPS; + if (getenv("LIBYUV_DISABLE_DSPR2")) { + cpu_info &= ~kCpuHasDSPR2; + } +#endif +#if defined(__arm__) || defined(__aarch64__) +// gcc -mfpu=neon defines __ARM_NEON__ +// __ARM_NEON__ generates code that requires Neon. NaCL also requires Neon. +// For Linux, /proc/cpuinfo can be tested but without that assume Neon. +#if defined(__ARM_NEON__) || defined(__native_client__) || !defined(__linux__) + cpu_info = kCpuHasNEON; +// For aarch64(arm64), /proc/cpuinfo's feature is not complete, e.g. no neon +// flag in it. +// So for aarch64, neon enabling is hard coded here. +#endif +#if defined(__aarch64__) + cpu_info = kCpuHasNEON; +#else + // Linux arm parse text file for neon detect. + cpu_info = ArmCpuCaps("/proc/cpuinfo"); +#endif + cpu_info |= kCpuHasARM; + if (TestEnv("LIBYUV_DISABLE_NEON")) { + cpu_info &= ~kCpuHasNEON; + } +#endif // __arm__ + if (TestEnv("LIBYUV_DISABLE_ASM")) { + cpu_info = 0; + } + cpu_info |= kCpuInitialized; + cpu_info_ = cpu_info; + return cpu_info; +} + +// Note that use of this function is not thread safe. +LIBYUV_API +void MaskCpuFlags(int enable_flags) { + cpu_info_ = InitCpuFlags() & enable_flags; +} + +#ifdef __cplusplus +} // extern "C" +} // namespace libyuv +#endif |