/*
* Simd Library (http://ermig1979.github.io/Simd).
*
* Copyright (c) 2011-2022 Yermalayeu Ihar,
*               2022-2022 Souriya Trinh,
*               2022-2022 Fabien Spindler.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include "Simd/SimdCpu.h"

#include <stdio.h>
#include <vector>
#ifdef SIMD_CPP_2011_ENABLE
#include <thread>
#endif
#include <sstream>
#include <iostream>

#if defined(_MSC_VER)

#ifndef NOMINMAX
#define NOMINMAX
#endif
#include <windows.h>
#include <intrin.h>

#elif defined(__GNUC__)
#include <unistd.h>
#include <stdbool.h>
#include <stdlib.h>

#if defined(SIMD_X86_ENABLE) || defined(SIMD_X64_ENABLE)
#include <cpuid.h>
#endif

#if defined(SIMD_PPC_ENABLE) || defined(SIMD_PPC64_ENABLE) || defined(SIMD_ARM_ENABLE) || defined(SIMD_ARM64_ENABLE)
#include <fcntl.h>
#if !defined(__APPLE__)
#include <sys/auxv.h>
#if (defined(SIMD_ARM_ENABLE) || defined(SIMD_ARM64_ENABLE)) && !defined(__FreeBSD__)
#include <asm/hwcap.h>
#endif
#endif
#endif

#ifndef PATH_MAX
#ifdef _MAX_PATH
#define PATH_MAX _MAX_PATH
#else
#define PATH_MAX 1024
#endif
#endif

#else
# error Do not know how to detect CPU info
#endif

namespace Simd {
  namespace Base {
#if defined(SIMD_X86_ENABLE) || defined(SIMD_X64_ENABLE)
    bool CheckBit(int eax, int ecx, Cpuid::Register index, Cpuid::Bit bit) {
      unsigned int registers[4] = { 0, 0, 0, 0 };
#if defined(_MSC_VER)
      __cpuidex((int*)registers, eax, ecx);
#elif (defined __GNUC__)
      if (__get_cpuid_max(0, NULL) < eax)
        return false;
      __cpuid_count(eax, ecx,
                    registers[Cpuid::Eax],
                    registers[Cpuid::Ebx],
                    registers[Cpuid::Ecx],
                    registers[Cpuid::Edx]);
#else
#error Do not know how to detect CPU info!
#endif
      return (registers[index] & bit) == bit;
      }
#endif//defined(SIMD_X86_ENABLE) || defined(SIMD_X64_ENABLE)

#if defined(__GNUC__) && (defined(SIMD_PPC_ENABLE) || defined(SIMD_PPC64_ENABLE) || defined(SIMD_ARM_ENABLE) || defined(SIMD_ARM64_ENABLE)) && !defined(__APPLE__)
    bool CheckBit(int at, int bit) {
      bool result = false;
      int file = ::open("/proc/self/auxv", O_RDONLY);
      if (file < 0)
        return false;
      const ssize_t size = 64;
      unsigned long buffer[size];
      for (ssize_t count = size; count == size;) {
        count = ::read(file, buffer, sizeof(buffer)) / sizeof(unsigned long);
        for (int i = 0; i < count; i += 2) {
          if (buffer[i] == (unsigned)at) {
            result = !!(buffer[i + 1] & bit);
            count = 0;
            }
          if (buffer[i] == AT_NULL)
            count = 0;
          }
        }
      ::close(file);
      return result;
      }
#endif//defined(__GNUC__) && (defined(SIMD_PPC_ENABLE) || defined(SIMD_PPC64_ENABLE) || defined(SIMD_ARM_ENABLE) || defined(SIMD_ARM64_ENABLE)) && !defined(__APPLE__)

#ifdef SIMD_CPP_2011_ENABLE
    size_t CpuThreadNumber() {
      return std::thread::hardware_concurrency();
      }
#endif

#if defined(_MSC_VER)
    typedef SYSTEM_LOGICAL_PROCESSOR_INFORMATION Info;

    void GetLogicalProcessorInformation(std::vector<Info>& info) {
      DWORD size = 0;
      ::GetLogicalProcessorInformation(0, &size);
      info.resize(size / sizeof(Info));
      ::GetLogicalProcessorInformation(info.data(), &size);
      }

    size_t CpuSocketNumber() {
      std::vector<Info> info;
      GetLogicalProcessorInformation(info);
      size_t number = 0;
      for (size_t i = 0; i < info.size(); ++i)
        if (info[i].Relationship == ::RelationNumaNode)
          number++;
      return number;
      }

    size_t CpuCoreNumber() {
      std::vector<Info> info;
      GetLogicalProcessorInformation(info);
      size_t number = 0;
      for (size_t i = 0; i < info.size(); ++i)
        if (info[i].Relationship == ::RelationProcessorCore)
          number++;
      return number;
      }

    size_t CpuCacheSize(size_t level) {
      std::vector<Info> info;
      GetLogicalProcessorInformation(info);
      for (size_t i = 0; i < info.size(); ++i)
        if (info[i].Relationship == ::RelationCache && info[i].Cache.Level == level && (info[i].Cache.Type == ::CacheData || info[i].Cache.Type == CacheUnified))
          return info[i].Cache.Size;
      return 0;
      }
#elif defined(__GNUC__)
    size_t CpuSocketNumber() {
      uint32_t number = 0;
      ::FILE* p = ::popen("lscpu -b -p=Socket 2>/dev/null | grep -v '^#' | sort -u 2>/dev/null | wc -l 2>/dev/null", "r");
      if (p) {
        char buffer[PATH_MAX];
        while (::fgets(buffer, PATH_MAX, p));
        number = ::atoi(buffer);
        ::pclose(p);
        }
      return number;
      }

    size_t CpuCoreNumber() {
      uint32_t number = 0;
      ::FILE* p = ::popen("lscpu -b -p=Core 2>/dev/null | grep -v '^#' | sort -u 2>/dev/null | wc -l 2>/dev/null", "r");
      if (p) {
        char buffer[PATH_MAX];
        while (::fgets(buffer, PATH_MAX, p));
        number = ::atoi(buffer);
        ::pclose(p);
        }
      return number;
      }

    SIMD_INLINE size_t CorrectIfZero(size_t value, size_t otherwise) {
      return value ? value : otherwise;
      }

#if defined(_SC_LEVEL1_DCACHE_SIZE) && defined(_SC_LEVEL2_CACHE_SIZE) && defined(_SC_LEVEL3_CACHE_SIZE)
    size_t CpuCacheSize(size_t level) {
      switch (level) {
        case 1:
        {
        const size_t sz = ::sysconf(_SC_LEVEL1_DCACHE_SIZE) < 0 ? 0 : ::sysconf(_SC_LEVEL1_DCACHE_SIZE);
        return CorrectIfZero(sz, 32 * 1024);
        }
        case 2:
        {
        const size_t sz = ::sysconf(_SC_LEVEL2_CACHE_SIZE) < 0 ? 0 : ::sysconf(_SC_LEVEL2_CACHE_SIZE);
        return CorrectIfZero(sz, 256 * 1024);
        }
        case 3:
        {
        const size_t sz = ::sysconf(_SC_LEVEL3_CACHE_SIZE) < 0 ? 0 : ::sysconf(_SC_LEVEL3_CACHE_SIZE);
        return CorrectIfZero(sz, 2048 * 1024);
        }
        default:
          return 0;
        }
      }
#else
    size_t CpuCacheSize(size_t level) {
      switch (level) {
        case 1: return 32 * 1024;
        case 2: return 256 * 1024;
        case 3: return 2048 * 1024;
        default:
          return 0;
        }
      }
#endif

#else
#error This platform is unsupported!
#endif
    }

  namespace Cpu {
    const size_t SOCKET_NUMBER = Base::CpuSocketNumber();
    const size_t CORE_NUMBER = Base::CpuCoreNumber();
#ifdef SIMD_CPP_2011_ENABLE
    const size_t THREAD_NUMBER = Base::CpuThreadNumber();
#endif
    const size_t L1_CACHE_SIZE = Base::CpuCacheSize(1);
    const size_t L2_CACHE_SIZE = Base::CpuCacheSize(2);
    const size_t L3_CACHE_SIZE = Base::CpuCacheSize(3);
    }
  }