dolphin/Source/Core/Common/ArmCPUDetect.cpp
JosJuice 2b88a46b1a Common: Set bFMA to true for AArch64
Without this, the code added in ac28b89 misbehaves and considers
AArch64 netplay clients to not have hardware FMA support, telling
all clients to disable FMA support, which causes a desync between
x64 and AArch64 due to JitArm64 not being able to disable FMA support.
2021-06-14 15:51:59 +02:00

141 lines
3.0 KiB
C++

// Copyright 2013 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.
#include <cstring>
#include <fstream>
#include <sstream>
#include <string>
#include <thread>
#if !defined(_WIN32) && !defined(__APPLE__)
#ifndef __FreeBSD__
#include <asm/hwcap.h>
#endif
#include <sys/auxv.h>
#include <unistd.h>
#endif
#include <fmt/format.h>
#include "Common/CPUDetect.h"
#include "Common/CommonTypes.h"
#include "Common/FileUtil.h"
#ifndef WIN32
const char procfile[] = "/proc/cpuinfo";
static std::string GetCPUString()
{
const std::string marker = "Hardware\t: ";
std::string cpu_string = "Unknown";
std::string line;
std::ifstream file;
File::OpenFStream(file, procfile, std::ios_base::in);
if (!file)
return cpu_string;
while (std::getline(file, line))
{
if (line.find(marker) != std::string::npos)
{
cpu_string = line.substr(marker.length());
break;
}
}
return cpu_string;
}
#endif
CPUInfo cpu_info;
CPUInfo::CPUInfo()
{
Detect();
}
// Detects the various CPU features
void CPUInfo::Detect()
{
// Set some defaults here
HTT = false;
OS64bit = true;
CPU64bit = true;
Mode64bit = true;
vendor = CPUVendor::ARM;
bFMA = true;
bFlushToZero = true;
bAFP = false;
#ifdef __APPLE__
num_cores = std::thread::hardware_concurrency();
// M-series CPUs have all of these
bFP = true;
bASIMD = true;
bAES = true;
bSHA1 = true;
bSHA2 = true;
bCRC32 = true;
#elif defined(_WIN32)
num_cores = std::thread::hardware_concurrency();
// Windows does not provide any mechanism for querying the system registers on ARMv8, unlike Linux
// which traps the register reads and emulates them in the kernel. There are environment variables
// containing some of the CPU-specific values, which we could use for a lookup table in the
// future. For now, assume all features are present as all known devices which are Windows-on-ARM
// compatible also support these extensions.
bFP = true;
bASIMD = true;
bAES = true;
bCRC32 = true;
bSHA1 = true;
bSHA2 = true;
#else
// Get the information about the CPU
num_cores = sysconf(_SC_NPROCESSORS_CONF);
strncpy(cpu_string, GetCPUString().c_str(), sizeof(cpu_string));
#ifdef __FreeBSD__
u_long hwcaps = 0;
elf_aux_info(AT_HWCAP, &hwcaps, sizeof(u_long));
#else
unsigned long hwcaps = getauxval(AT_HWCAP);
#endif
bFP = hwcaps & HWCAP_FP;
bASIMD = hwcaps & HWCAP_ASIMD;
bAES = hwcaps & HWCAP_AES;
bCRC32 = hwcaps & HWCAP_CRC32;
bSHA1 = hwcaps & HWCAP_SHA1;
bSHA2 = hwcaps & HWCAP_SHA2;
#endif
}
// Turn the CPU info into a string we can show
std::string CPUInfo::Summarize()
{
std::string sum;
if (num_cores == 1)
sum = fmt::format("{}, 1 core", cpu_string);
else
sum = fmt::format("{}, {} cores", cpu_string, num_cores);
if (bAES)
sum += ", AES";
if (bCRC32)
sum += ", CRC32";
if (bSHA1)
sum += ", SHA1";
if (bSHA2)
sum += ", SHA2";
if (CPU64bit)
sum += ", 64-bit";
return sum;
}