// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
// SPDX-FileCopyrightText: Copyright 2013 Dolphin Emulator Project / 2015 Citra Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#include <array>
#include <cstring>
#include <fstream>
#include <iterator>
#include <optional>
#include <string_view>
#include <thread>
#include <vector>
#include "common/bit_util.h"
#include "common/common_types.h"
#include "common/logging/log.h"
#include "common/x64/cpu_detect.h"
#ifdef _WIN32
#include <windows.h>
#endif
#ifdef _MSC_VER
#include <intrin.h>
static inline u64 xgetbv(u32 index) {
return _xgetbv(index);
}
#else
#if defined(__DragonFly__) || defined(__FreeBSD__)
// clang-format off
#include <sys/types.h>
#include <machine/cpufunc.h>
// clang-format on
#endif
static inline void __cpuidex(int info[4], u32 function_id, u32 subfunction_id) {
#if defined(__DragonFly__) || defined(__FreeBSD__)
// Despite the name, this is just do_cpuid() with ECX as second input.
cpuid_count((u_int)function_id, (u_int)subfunction_id, (u_int*)info);
#else
info[0] = function_id; // eax
info[2] = subfunction_id; // ecx
__asm__("cpuid"
: "=a"(info[0]), "=b"(info[1]), "=c"(info[2]), "=d"(info[3])
: "a"(function_id), "c"(subfunction_id));
#endif
}
static inline void __cpuid(int info[4], u32 function_id) {
return __cpuidex(info, function_id, 0);
}
#define _XCR_XFEATURE_ENABLED_MASK 0
static inline u64 xgetbv(u32 index) {
u32 eax, edx;
__asm__ __volatile__("xgetbv" : "=a"(eax), "=d"(edx) : "c"(index));
return ((u64)edx << 32) | eax;
}
#endif // _MSC_VER
namespace Common {
CPUCaps::Manufacturer CPUCaps::ParseManufacturer(std::string_view brand_string) {
if (brand_string == "GenuineIntel") {
return Manufacturer::Intel;
} else if (brand_string == "AuthenticAMD") {
return Manufacturer::AMD;
} else if (brand_string == "HygonGenuine") {
return Manufacturer::Hygon;
}
return Manufacturer::Unknown;
}
// Detects the various CPU features
static CPUCaps Detect() {
CPUCaps caps = {};
// Assumes the CPU supports the CPUID instruction. Those that don't would likely not support
// yuzu at all anyway
int cpu_id[4];
// Detect CPU's CPUID capabilities and grab manufacturer string
__cpuid(cpu_id, 0x00000000);
const u32 max_std_fn = cpu_id[0]; // EAX
std::memset(caps.brand_string, 0, std::size(caps.brand_string));
std::memcpy(&caps.brand_string[0], &cpu_id[1], sizeof(u32));
std::memcpy(&caps.brand_string[4], &cpu_id[3], sizeof(u32));
std::memcpy(&caps.brand_string[8], &cpu_id[2], sizeof(u32));
caps.manufacturer = CPUCaps::ParseManufacturer(caps.brand_string);
// Set reasonable default cpu string even if brand string not available
std::strncpy(caps.cpu_string, caps.brand_string, std::size(caps.brand_string));
__cpuid(cpu_id, 0x80000000);
const u32 max_ex_fn = cpu_id[0];
// Detect family and other miscellaneous features
if (max_std_fn >= 1) {
__cpuid(cpu_id, 0x00000001);
caps.sse = Common::Bit<25>(cpu_id[3]);
caps.sse2 = Common::Bit<26>(cpu_id[3]);
caps.sse3 = Common::Bit<0>(cpu_id[2]);
caps.pclmulqdq = Common::Bit<1>(cpu_id[2]);
caps.ssse3 = Common::Bit<9>(cpu_id[2]);
caps.sse4_1 = Common::Bit<19>(cpu_id[2]);
caps.sse4_2 = Common::Bit<20>(cpu_id[2]);
caps.movbe = Common::Bit<22>(cpu_id[2]);
caps.popcnt = Common::Bit<23>(cpu_id[2]);
caps.aes = Common::Bit<25>(cpu_id[2]);
caps.f16c = Common::Bit<29>(cpu_id[2]);
// AVX support requires 3 separate checks:
// - Is the AVX bit set in CPUID?
// - Is the XSAVE bit set in CPUID?
// - XGETBV result has the XCR bit set.
if (Common::Bit<28>(cpu_id[2]) && Common::Bit<27>(cpu_id[2])) {
if ((xgetbv(_XCR_XFEATURE_ENABLED_MASK) & 0x6) == 0x6) {
caps.avx = true;
if (Common::Bit<12>(cpu_id[2]))
caps.fma = true;
}
}
if (max_std_fn >= 7) {
__cpuidex(cpu_id, 0x00000007, 0x00000000);
// Can't enable AVX{2,512} unless the XSAVE/XGETBV checks above passed
if (caps.avx) {
caps.avx2 = Common::Bit<5>(cpu_id[1]);
caps.avx512f = Common::Bit<16>(cpu_id[1]);
caps.avx512dq = Common::Bit<17>(cpu_id[1]);
caps.avx512cd = Common::Bit<28>(cpu_id[1]);
caps.avx512bw = Common::Bit<30>(cpu_id[1]);
caps.avx512vl = Common::Bit<31>(cpu_id[1]);
caps.avx512vbmi = Common::Bit<1>(cpu_id[2]);
caps.avx512bitalg = Common::Bit<12>(cpu_id[2]);
}
caps.bmi1 = Common::Bit<3>(cpu_id[1]);
caps.bmi2 = Common::Bit<8>(cpu_id[1]);
caps.sha = Common::Bit<29>(cpu_id[1]);
caps.waitpkg = Common::Bit<5>(cpu_id[2]);
caps.gfni = Common::Bit<8>(cpu_id[2]);
__cpuidex(cpu_id, 0x00000007, 0x00000001);
caps.avx_vnni = caps.avx && Common::Bit<4>(cpu_id[0]);
}
}
if (max_ex_fn >= 0x80000004) {
// Extract CPU model string
__cpuid(cpu_id, 0x80000002);
std::memcpy(caps.cpu_string, cpu_id, sizeof(cpu_id));
__cpuid(cpu_id, 0x80000003);
std::memcpy(caps.cpu_string + 16, cpu_id, sizeof(cpu_id));
__cpuid(cpu_id, 0x80000004);
std::memcpy(caps.cpu_string + 32, cpu_id, sizeof(cpu_id));
}
if (max_ex_fn >= 0x80000001) {
// Check for more features
__cpuid(cpu_id, 0x80000001);
caps.lzcnt = Common::Bit<5>(cpu_id[2]);
caps.fma4 = Common::Bit<16>(cpu_id[2]);
}
if (max_ex_fn >= 0x80000007) {
__cpuid(cpu_id, 0x80000007);
caps.invariant_tsc = Common::Bit<8>(cpu_id[3]);
}
if (max_std_fn >= 0x15) {
__cpuid(cpu_id, 0x15);
caps.tsc_crystal_ratio_denominator = cpu_id[0];
caps.tsc_crystal_ratio_numerator = cpu_id[1];
caps.crystal_frequency = cpu_id[2];
// Some CPU models might not return a crystal frequency.
// The CPU model can be detected to use the values from turbostat
// https://github.com/torvalds/linux/blob/master/tools/power/x86/turbostat/turbostat.c#L5569
// but it's easier to just estimate the TSC tick rate for these cases.
if (caps.tsc_crystal_ratio_denominator) {
caps.tsc_frequency = static_cast<u64>(caps.crystal_frequency) *
caps.tsc_crystal_ratio_numerator /
caps.tsc_crystal_ratio_denominator;
}
}
if (max_std_fn >= 0x16) {
__cpuid(cpu_id, 0x16);
caps.base_frequency = cpu_id[0];
caps.max_frequency = cpu_id[1];
caps.bus_frequency = cpu_id[2];
}
return caps;
}
const CPUCaps& GetCPUCaps() {
static CPUCaps caps = Detect();
return caps;
}
std::optional<int> GetProcessorCount() {
#if defined(_WIN32)
// Get the buffer length.
DWORD length = 0;
GetLogicalProcessorInformation(nullptr, &length);
if (GetLastError() != ERROR_INSUFFICIENT_BUFFER) {
LOG_ERROR(Frontend, "Failed to query core count.");
return std::nullopt;
}
std::vector<SYSTEM_LOGICAL_PROCESSOR_INFORMATION> buffer(
length / sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION));
// Now query the core count.
if (!GetLogicalProcessorInformation(buffer.data(), &length)) {
LOG_ERROR(Frontend, "Failed to query core count.");
return std::nullopt;
}
return static_cast<int>(
std::count_if(buffer.cbegin(), buffer.cend(), [](const auto& proc_info) {
return proc_info.Relationship == RelationProcessorCore;
}));
#elif defined(__unix__)
const int thread_count = std::thread::hardware_concurrency();
std::ifstream smt("/sys/devices/system/cpu/smt/active");
char state = '0';
if (smt) {
smt.read(&state, sizeof(state));
}
switch (state) {
case '0':
return thread_count;
case '1':
return thread_count / 2;
default:
return std::nullopt;
}
#else
// Shame on you
return std::nullopt;
#endif
}
} // namespace Common
