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Diffstat (limited to 'security/sandbox/chromium/base/cpu.cc')
-rw-r--r-- | security/sandbox/chromium/base/cpu.cc | 296 |
1 files changed, 0 insertions, 296 deletions
diff --git a/security/sandbox/chromium/base/cpu.cc b/security/sandbox/chromium/base/cpu.cc deleted file mode 100644 index 713544566..000000000 --- a/security/sandbox/chromium/base/cpu.cc +++ /dev/null @@ -1,296 +0,0 @@ -// Copyright (c) 2012 The Chromium Authors. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be -// found in the LICENSE file. - -#include "base/cpu.h" - -#include <limits.h> -#include <stddef.h> -#include <stdint.h> -#include <stdlib.h> -#include <string.h> - -#include <algorithm> - -#include "base/macros.h" -#include "base/strings/string_piece.h" -#include "build/build_config.h" - -#if defined(ARCH_CPU_ARM_FAMILY) && (defined(OS_ANDROID) || defined(OS_LINUX)) -#include "base/files/file_util.h" -#include "base/lazy_instance.h" -#endif - -#if defined(ARCH_CPU_X86_FAMILY) -#if defined(_MSC_VER) -#include <intrin.h> -#include <immintrin.h> // For _xgetbv() -#endif -#endif - -namespace base { - -CPU::CPU() - : signature_(0), - type_(0), - family_(0), - model_(0), - stepping_(0), - ext_model_(0), - ext_family_(0), - has_mmx_(false), - has_sse_(false), - has_sse2_(false), - has_sse3_(false), - has_ssse3_(false), - has_sse41_(false), - has_sse42_(false), - has_avx_(false), - has_avx2_(false), - has_aesni_(false), - has_non_stop_time_stamp_counter_(false), - has_broken_neon_(false), - cpu_vendor_("unknown") { - Initialize(); -} - -namespace { - -#if defined(ARCH_CPU_X86_FAMILY) -#ifndef _MSC_VER - -#if defined(__pic__) && defined(__i386__) - -void __cpuid(int cpu_info[4], int info_type) { - __asm__ volatile ( - "mov %%ebx, %%edi\n" - "cpuid\n" - "xchg %%edi, %%ebx\n" - : "=a"(cpu_info[0]), "=D"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3]) - : "a"(info_type) - ); -} - -#else - -void __cpuid(int cpu_info[4], int info_type) { - __asm__ volatile ( - "cpuid\n" - : "=a"(cpu_info[0]), "=b"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3]) - : "a"(info_type) - ); -} - -#endif - -// _xgetbv returns the value of an Intel Extended Control Register (XCR). -// Currently only XCR0 is defined by Intel so |xcr| should always be zero. -uint64_t _xgetbv(uint32_t xcr) { - uint32_t eax, edx; - - __asm__ volatile ( - "xgetbv" : "=a"(eax), "=d"(edx) : "c"(xcr)); - return (static_cast<uint64_t>(edx) << 32) | eax; -} - -#endif // !_MSC_VER -#endif // ARCH_CPU_X86_FAMILY - -#if defined(ARCH_CPU_ARM_FAMILY) && (defined(OS_ANDROID) || defined(OS_LINUX)) -class LazyCpuInfoValue { - public: - LazyCpuInfoValue() : has_broken_neon_(false) { - // This function finds the value from /proc/cpuinfo under the key "model - // name" or "Processor". "model name" is used in Linux 3.8 and later (3.7 - // and later for arm64) and is shown once per CPU. "Processor" is used in - // earler versions and is shown only once at the top of /proc/cpuinfo - // regardless of the number CPUs. - const char kModelNamePrefix[] = "model name\t: "; - const char kProcessorPrefix[] = "Processor\t: "; - - // This function also calculates whether we believe that this CPU has a - // broken NEON unit based on these fields from cpuinfo: - unsigned implementer = 0, architecture = 0, variant = 0, part = 0, - revision = 0; - const struct { - const char key[17]; - unsigned int* result; - } kUnsignedValues[] = { - {"CPU implementer", &implementer}, - {"CPU architecture", &architecture}, - {"CPU variant", &variant}, - {"CPU part", &part}, - {"CPU revision", &revision}, - }; - - std::string contents; - ReadFileToString(FilePath("/proc/cpuinfo"), &contents); - DCHECK(!contents.empty()); - if (contents.empty()) { - return; - } - - std::istringstream iss(contents); - std::string line; - while (std::getline(iss, line)) { - if (brand_.empty() && - (line.compare(0, strlen(kModelNamePrefix), kModelNamePrefix) == 0 || - line.compare(0, strlen(kProcessorPrefix), kProcessorPrefix) == 0)) { - brand_.assign(line.substr(strlen(kModelNamePrefix))); - } - - for (size_t i = 0; i < arraysize(kUnsignedValues); i++) { - const char *key = kUnsignedValues[i].key; - const size_t len = strlen(key); - - if (line.compare(0, len, key) == 0 && - line.size() >= len + 1 && - (line[len] == '\t' || line[len] == ' ' || line[len] == ':')) { - size_t colon_pos = line.find(':', len); - if (colon_pos == std::string::npos) { - continue; - } - - const StringPiece line_sp(line); - StringPiece value_sp = line_sp.substr(colon_pos + 1); - while (!value_sp.empty() && - (value_sp[0] == ' ' || value_sp[0] == '\t')) { - value_sp = value_sp.substr(1); - } - - // The string may have leading "0x" or not, so we use strtoul to - // handle that. - char* endptr; - std::string value(value_sp.as_string()); - unsigned long int result = strtoul(value.c_str(), &endptr, 0); - if (*endptr == 0 && result <= UINT_MAX) { - *kUnsignedValues[i].result = result; - } - } - } - } - - has_broken_neon_ = - implementer == 0x51 && - architecture == 7 && - variant == 1 && - part == 0x4d && - revision == 0; - } - - const std::string& brand() const { return brand_; } - bool has_broken_neon() const { return has_broken_neon_; } - - private: - std::string brand_; - bool has_broken_neon_; - DISALLOW_COPY_AND_ASSIGN(LazyCpuInfoValue); -}; - -base::LazyInstance<LazyCpuInfoValue>::Leaky g_lazy_cpuinfo = - LAZY_INSTANCE_INITIALIZER; - -#endif // defined(ARCH_CPU_ARM_FAMILY) && (defined(OS_ANDROID) || - // defined(OS_LINUX)) - -} // anonymous namespace - -void CPU::Initialize() { -#if defined(ARCH_CPU_X86_FAMILY) - int cpu_info[4] = {-1}; - char cpu_string[48]; - - // __cpuid with an InfoType argument of 0 returns the number of - // valid Ids in CPUInfo[0] and the CPU identification string in - // the other three array elements. The CPU identification string is - // not in linear order. The code below arranges the information - // in a human readable form. The human readable order is CPUInfo[1] | - // CPUInfo[3] | CPUInfo[2]. CPUInfo[2] and CPUInfo[3] are swapped - // before using memcpy to copy these three array elements to cpu_string. - __cpuid(cpu_info, 0); - int num_ids = cpu_info[0]; - std::swap(cpu_info[2], cpu_info[3]); - memcpy(cpu_string, &cpu_info[1], 3 * sizeof(cpu_info[1])); - cpu_vendor_.assign(cpu_string, 3 * sizeof(cpu_info[1])); - - // Interpret CPU feature information. - if (num_ids > 0) { - int cpu_info7[4] = {0}; - __cpuid(cpu_info, 1); - if (num_ids >= 7) { - __cpuid(cpu_info7, 7); - } - signature_ = cpu_info[0]; - stepping_ = cpu_info[0] & 0xf; - model_ = ((cpu_info[0] >> 4) & 0xf) + ((cpu_info[0] >> 12) & 0xf0); - family_ = (cpu_info[0] >> 8) & 0xf; - type_ = (cpu_info[0] >> 12) & 0x3; - ext_model_ = (cpu_info[0] >> 16) & 0xf; - ext_family_ = (cpu_info[0] >> 20) & 0xff; - has_mmx_ = (cpu_info[3] & 0x00800000) != 0; - has_sse_ = (cpu_info[3] & 0x02000000) != 0; - has_sse2_ = (cpu_info[3] & 0x04000000) != 0; - has_sse3_ = (cpu_info[2] & 0x00000001) != 0; - has_ssse3_ = (cpu_info[2] & 0x00000200) != 0; - has_sse41_ = (cpu_info[2] & 0x00080000) != 0; - has_sse42_ = (cpu_info[2] & 0x00100000) != 0; - // AVX instructions will generate an illegal instruction exception unless - // a) they are supported by the CPU, - // b) XSAVE is supported by the CPU and - // c) XSAVE is enabled by the kernel. - // See http://software.intel.com/en-us/blogs/2011/04/14/is-avx-enabled - // - // In addition, we have observed some crashes with the xgetbv instruction - // even after following Intel's example code. (See crbug.com/375968.) - // Because of that, we also test the XSAVE bit because its description in - // the CPUID documentation suggests that it signals xgetbv support. - has_avx_ = - (cpu_info[2] & 0x10000000) != 0 && - (cpu_info[2] & 0x04000000) != 0 /* XSAVE */ && - (cpu_info[2] & 0x08000000) != 0 /* OSXSAVE */ && - (_xgetbv(0) & 6) == 6 /* XSAVE enabled by kernel */; - has_aesni_ = (cpu_info[2] & 0x02000000) != 0; - has_avx2_ = has_avx_ && (cpu_info7[1] & 0x00000020) != 0; - } - - // Get the brand string of the cpu. - __cpuid(cpu_info, 0x80000000); - const int parameter_end = 0x80000004; - int max_parameter = cpu_info[0]; - - if (cpu_info[0] >= parameter_end) { - char* cpu_string_ptr = cpu_string; - - for (int parameter = 0x80000002; parameter <= parameter_end && - cpu_string_ptr < &cpu_string[sizeof(cpu_string)]; parameter++) { - __cpuid(cpu_info, parameter); - memcpy(cpu_string_ptr, cpu_info, sizeof(cpu_info)); - cpu_string_ptr += sizeof(cpu_info); - } - cpu_brand_.assign(cpu_string, cpu_string_ptr - cpu_string); - } - - const int parameter_containing_non_stop_time_stamp_counter = 0x80000007; - if (max_parameter >= parameter_containing_non_stop_time_stamp_counter) { - __cpuid(cpu_info, parameter_containing_non_stop_time_stamp_counter); - has_non_stop_time_stamp_counter_ = (cpu_info[3] & (1 << 8)) != 0; - } -#elif defined(ARCH_CPU_ARM_FAMILY) && (defined(OS_ANDROID) || defined(OS_LINUX)) - cpu_brand_.assign(g_lazy_cpuinfo.Get().brand()); - has_broken_neon_ = g_lazy_cpuinfo.Get().has_broken_neon(); -#endif -} - -CPU::IntelMicroArchitecture CPU::GetIntelMicroArchitecture() const { - if (has_avx2()) return AVX2; - if (has_avx()) return AVX; - if (has_sse42()) return SSE42; - if (has_sse41()) return SSE41; - if (has_ssse3()) return SSSE3; - if (has_sse3()) return SSE3; - if (has_sse2()) return SSE2; - if (has_sse()) return SSE; - return PENTIUM; -} - -} // namespace base |