citra/src/common/x64/cpu_detect.cpp

188 lines
5.4 KiB
C++

// Copyright 2013 Dolphin Emulator Project / 2015 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <cstring>
#include <string>
#include <thread>
#include "common/common_types.h"
#include "cpu_detect.h"
namespace Common {
#ifndef _MSC_VER
#ifdef __FreeBSD__
#include <sys/types.h>
#include <machine/cpufunc.h>
#endif
static inline void __cpuidex(int info[4], int function_id, int subfunction_id) {
#ifdef __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], int function_id) {
return __cpuidex(info, function_id, 0);
}
#define _XCR_XFEATURE_ENABLED_MASK 0
static u64 _xgetbv(u32 index) {
u32 eax, edx;
__asm__ __volatile__("xgetbv" : "=a"(eax), "=d"(edx) : "c"(index));
return ((u64)edx << 32) | eax;
}
#endif // ifndef _MSC_VER
// Detects the various CPU features
static CPUCaps Detect() {
CPUCaps caps = {};
caps.num_cores = std::thread::hardware_concurrency();
// Assumes the CPU supports the CPUID instruction. Those that don't would likely not support
// Citra at all anyway
int cpu_id[4];
memset(caps.brand_string, 0, sizeof(caps.brand_string));
// Detect CPU's CPUID capabilities and grab CPU string
__cpuid(cpu_id, 0x00000000);
u32 max_std_fn = cpu_id[0]; // EAX
std::memcpy(&caps.brand_string[0], &cpu_id[1], sizeof(int));
std::memcpy(&caps.brand_string[4], &cpu_id[3], sizeof(int));
std::memcpy(&caps.brand_string[8], &cpu_id[2], sizeof(int));
__cpuid(cpu_id, 0x80000000);
u32 max_ex_fn = cpu_id[0];
if (!strcmp(caps.brand_string, "GenuineIntel"))
caps.vendor = CPUVendor::INTEL;
else if (!strcmp(caps.brand_string, "AuthenticAMD"))
caps.vendor = CPUVendor::AMD;
else
caps.vendor = CPUVendor::OTHER;
// Set reasonable default brand string even if brand string not available
strcpy(caps.cpu_string, caps.brand_string);
// Detect family and other miscellaneous features
if (max_std_fn >= 1) {
__cpuid(cpu_id, 0x00000001);
if ((cpu_id[3] >> 25) & 1) caps.sse = true;
if ((cpu_id[3] >> 26) & 1) caps.sse2 = true;
if ((cpu_id[2]) & 1) caps.sse3 = true;
if ((cpu_id[2] >> 9) & 1) caps.ssse3 = true;
if ((cpu_id[2] >> 19) & 1) caps.sse4_1 = true;
if ((cpu_id[2] >> 20) & 1) caps.sse4_2 = true;
if ((cpu_id[2] >> 22) & 1) caps.movbe = true;
if ((cpu_id[2] >> 25) & 1) caps.aes = true;
if ((cpu_id[3] >> 24) & 1) {
caps.fxsave_fxrstor = true;
}
// 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 (((cpu_id[2] >> 28) & 1) && ((cpu_id[2] >> 27) & 1)) {
if ((_xgetbv(_XCR_XFEATURE_ENABLED_MASK) & 0x6) == 0x6) {
caps.avx = true;
if ((cpu_id[2] >> 12) & 1)
caps.fma = true;
}
}
if (max_std_fn >= 7) {
__cpuidex(cpu_id, 0x00000007, 0x00000000);
// Can't enable AVX2 unless the XSAVE/XGETBV checks above passed
if ((cpu_id[1] >> 5) & 1)
caps.avx2 = caps.avx;
if ((cpu_id[1] >> 3) & 1)
caps.bmi1 = true;
if ((cpu_id[1] >> 8) & 1)
caps.bmi2 = true;
}
}
caps.flush_to_zero = caps.sse;
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);
if (cpu_id[2] & 1) caps.lahf_sahf_64 = true;
if ((cpu_id[2] >> 5) & 1) caps.lzcnt = true;
if ((cpu_id[2] >> 16) & 1) caps.fma4 = true;
if ((cpu_id[3] >> 29) & 1) caps.long_mode = true;
}
return caps;
}
const CPUCaps& GetCPUCaps() {
static CPUCaps caps = Detect();
return caps;
}
std::string GetCPUCapsString() {
auto caps = GetCPUCaps();
std::string sum(caps.cpu_string);
sum += " (";
sum += caps.brand_string;
sum += ")";
if (caps.sse) sum += ", SSE";
if (caps.sse2) {
sum += ", SSE2";
if (!caps.flush_to_zero) sum += " (without DAZ)";
}
if (caps.sse3) sum += ", SSE3";
if (caps.ssse3) sum += ", SSSE3";
if (caps.sse4_1) sum += ", SSE4.1";
if (caps.sse4_2) sum += ", SSE4.2";
if (caps.avx) sum += ", AVX";
if (caps.avx2) sum += ", AVX2";
if (caps.bmi1) sum += ", BMI1";
if (caps.bmi2) sum += ", BMI2";
if (caps.fma) sum += ", FMA";
if (caps.aes) sum += ", AES";
if (caps.movbe) sum += ", MOVBE";
if (caps.long_mode) sum += ", 64-bit support";
return sum;
}
} // namespace Common