/****************************************************************************
 * Copyright (C) 2014-2017 Intel Corporation.   All Rights Reserved.
 *
 * 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 (including the next
 * paragraph) 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.
 ****************************************************************************/

#ifndef __SWR_OS_H__
#define __SWR_OS_H__

#include <cstddef>
#include "core/knobs.h"

#if (defined(FORCE_WINDOWS) || defined(_WIN32)) && !defined(FORCE_LINUX)

#define SWR_API __cdecl
#define SWR_VISIBLE __declspec(dllexport)

#ifndef NOMINMAX
#undef UNICODE
#define NOMINMAX
#include <windows.h>
#undef NOMINMAX
#define UNICODE
#else
#include <windows.h>
#endif
#include <intrin.h>
#include <cstdint>

#if defined(MemoryFence)
// Windows.h defines MemoryFence as _mm_mfence, but this conflicts with llvm::sys::MemoryFence
#undef MemoryFence
#endif

#if defined(_MSC_VER)
#define OSALIGN(RWORD, WIDTH) __declspec(align(WIDTH)) RWORD
#elif defined(__GNUC__)
#define OSALIGN(RWORD, WIDTH) RWORD __attribute__((aligned(WIDTH)))
#endif

#if defined(_DEBUG)
// We compile Debug builds with inline function expansion enabled.  This allows
// functions compiled with __forceinline to be inlined even in Debug builds.
// The inline_depth(0) pragma below will disable inline function expansion for
// normal INLINE / inline functions, but not for __forceinline functions.
// Our SIMD function wrappers (see simdlib.hpp) use __forceinline even in
// Debug builds.
#define INLINE inline
#pragma inline_depth(0)
#else
// Use of __forceinline increases compile time dramatically in release builds
// and provides almost 0 measurable benefit.  Disable until we have a compelling
// use-case
// #define INLINE __forceinline
#define INLINE inline
#endif
#ifndef FORCEINLINE
#define FORCEINLINE __forceinline
#endif

#define DEBUGBREAK __debugbreak()

#define PRAGMA_WARNING_PUSH_DISABLE(...) \
    __pragma(warning(push));             \
    __pragma(warning(disable : __VA_ARGS__));

#define PRAGMA_WARNING_POP() __pragma(warning(pop))

static inline void* AlignedMalloc(size_t _Size, size_t _Alignment)
{
    return _aligned_malloc(_Size, _Alignment);
}

static inline void AlignedFree(void* p)
{
    return _aligned_free(p);
}

#if defined(_WIN64)
#define BitScanReverseSizeT BitScanReverse64
#define BitScanForwardSizeT BitScanForward64
#define _mm_popcount_sizeT _mm_popcnt_u64
#else
#define BitScanReverseSizeT BitScanReverse
#define BitScanForwardSizeT BitScanForward
#define _mm_popcount_sizeT _mm_popcnt_u32
#endif

#if !defined(_WIN64)
inline unsigned char _BitScanForward64(unsigned long* Index, uint64_t Mask)
{
#ifdef __GNUC__
    *Index = __builtin_ctzll(Mask);
#else
    *Index = 0;
    for (int i = 0; i < 64; ++ i)
      if ((1ULL << i) & Mask)
        *Index = i;
#endif
    return (Mask != 0);
}

inline unsigned char _BitScanReverse64(unsigned long* Index, uint64_t Mask)
{
#ifdef __GNUC__
    *Index = 63 - __builtin_clzll(Mask);
#else
    *Index = 0;
    for (int i = 63; i >= 0; -- i)
      if ((1ULL << i) & Mask)
        *Index = i;
#endif
    return (Mask != 0);
}
#endif

#elif defined(__APPLE__) || defined(FORCE_LINUX) || defined(__linux__) || defined(__gnu_linux__)

#define SWR_API
#define SWR_VISIBLE __attribute__((visibility("default")))

#include <stdlib.h>
#include <string.h>
#include <x86intrin.h>
#include <stdint.h>
#include <sys/types.h>
#include <unistd.h>
#include <sys/stat.h>
#include <stdio.h>
#include <limits.h>

typedef void         VOID;
typedef void*        LPVOID;
typedef int          INT;
typedef unsigned int UINT;
typedef void*        HANDLE;
typedef int          LONG;
typedef unsigned int DWORD;

#undef FALSE
#define FALSE 0

#undef TRUE
#define TRUE 1

#define MAX_PATH PATH_MAX

#define OSALIGN(RWORD, WIDTH) RWORD __attribute__((aligned(WIDTH)))
#ifndef INLINE
#define INLINE __inline
#endif
#ifndef FORCEINLINE
#define FORCEINLINE INLINE
#endif
#define DEBUGBREAK asm("int $3")

#if !defined(__CYGWIN__)

#ifndef __cdecl
#define __cdecl
#endif
#ifndef __stdcall
#define __stdcall
#endif

#if defined(__GNUC__) && !defined(__INTEL_COMPILER)
#define __declspec(x) __declspec_##x
#define __declspec_align(y) __attribute__((aligned(y)))
#define __declspec_deprecated __attribute__((deprecated))
#define __declspec_dllexport
#define __declspec_dllimport
#define __declspec_noinline __attribute__((__noinline__))
#define __declspec_nothrow __attribute__((nothrow))
#define __declspec_novtable
#define __declspec_thread __thread
#else
#define __declspec(X)
#endif

#endif

#define GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__)

#if !defined(__clang__) && (__GNUC__) && (GCC_VERSION < 40500)
inline uint64_t      __rdtsc()
{
    long low, high;
    asm volatile("rdtsc" : "=a"(low), "=d"(high));
    return (low | ((uint64_t)high << 32));
}
#endif

#if !defined(__clang__) && !defined(__INTEL_COMPILER)
// Intrinsic not defined in gcc < 10
#if (__GNUC__) && (GCC_VERSION < 100000)
static INLINE void _mm256_storeu2_m128i(__m128i* hi, __m128i* lo, __m256i a)
{
    _mm_storeu_si128((__m128i*)lo, _mm256_castsi256_si128(a));
    _mm_storeu_si128((__m128i*)hi, _mm256_extractf128_si256(a, 0x1));
}
#endif

// gcc prior to 4.9 doesn't have _mm*_undefined_*
#if (__GNUC__) && (GCC_VERSION < 40900)
#define _mm_undefined_si128 _mm_setzero_si128
#define _mm256_undefined_ps _mm256_setzero_ps
#endif
#endif

inline unsigned char _BitScanForward64(unsigned long* Index, uint64_t Mask)
{
    *Index = __builtin_ctzll(Mask);
    return (Mask != 0);
}

inline unsigned char _BitScanForward(unsigned long* Index, uint32_t Mask)
{
    *Index = __builtin_ctz(Mask);
    return (Mask != 0);
}

inline unsigned char _BitScanReverse64(unsigned long* Index, uint64_t Mask)
{
    *Index = 63 - __builtin_clzll(Mask);
    return (Mask != 0);
}

inline unsigned char _BitScanReverse(unsigned long* Index, uint32_t Mask)
{
    *Index = 31 - __builtin_clz(Mask);
    return (Mask != 0);
}

inline void* AlignedMalloc(size_t size, size_t alignment)
{
    void* ret;
    if (posix_memalign(&ret, alignment, size))
    {
        return NULL;
    }
    return ret;
}

static inline void AlignedFree(void* p)
{
    free(p);
}

#define _countof(a) (sizeof(a) / sizeof(*(a)))

#define sprintf_s sprintf
#define strcpy_s(dst, size, src) strncpy(dst, src, size)
#define GetCurrentProcessId getpid

#define InterlockedCompareExchange(Dest, Exchange, Comparand) \
    __sync_val_compare_and_swap(Dest, Comparand, Exchange)
#define InterlockedExchangeAdd(Addend, Value) __sync_fetch_and_add(Addend, Value)
#define InterlockedDecrement(Append) __sync_sub_and_fetch(Append, 1)
#define InterlockedDecrement64(Append) __sync_sub_and_fetch(Append, 1)
#define InterlockedIncrement(Append) __sync_add_and_fetch(Append, 1)
#define InterlockedAdd(Addend, Value) __sync_add_and_fetch(Addend, Value)
#define InterlockedAdd64(Addend, Value) __sync_add_and_fetch(Addend, Value)
#define _ReadWriteBarrier() asm volatile("" ::: "memory")

#define PRAGMA_WARNING_PUSH_DISABLE(...)
#define PRAGMA_WARNING_POP()

#define ZeroMemory(dst, size) memset(dst, 0, size)
#else

#error Unsupported OS/system.

#endif

#define THREAD thread_local

// Universal types
typedef uint8_t  KILOBYTE[1024];
typedef KILOBYTE MEGABYTE[1024];
typedef MEGABYTE GIGABYTE[1024];

#define OSALIGNLINE(RWORD) OSALIGN(RWORD, 64)
#define OSALIGNSIMD(RWORD) OSALIGN(RWORD, KNOB_SIMD_BYTES)
#define OSALIGNSIMD16(RWORD) OSALIGN(RWORD, KNOB_SIMD16_BYTES)

#include "common/swr_assert.h"

#ifdef __GNUC__
#define ATTR_UNUSED __attribute__((unused))
#else
#define ATTR_UNUSED
#endif

#define SWR_FUNC(_retType, _funcName, /* args */...)        \
    typedef _retType(SWR_API* PFN##_funcName)(__VA_ARGS__); \
    _retType SWR_API _funcName(__VA_ARGS__);

// Defined in os.cpp
void SWR_API SetCurrentThreadName(const char* pThreadName);
void SWR_API CreateDirectoryPath(const std::string& path);

/// Execute Command (block until finished)
/// @returns process exit value
int SWR_API
    ExecCmd(const std::string& cmd,                ///< (In) Command line string
            const char*  pOptEnvStrings = nullptr, ///< (Optional In) Environment block for new process
            std::string* pOptStdOut     = nullptr,   ///< (Optional Out) Standard Output text
            std::string* pOptStdErr     = nullptr,   ///< (Optional Out) Standard Error text
            const std::string* pOptStdIn = nullptr); ///< (Optional In) Standard Input text


/// Helper for setting up FP state
/// @returns old csr state
static INLINE uint32_t SetOptimalVectorCSR()
{
    uint32_t oldCSR = _mm_getcsr();

    uint32_t newCSR = (oldCSR & ~(_MM_ROUND_MASK | _MM_DENORMALS_ZERO_MASK | _MM_FLUSH_ZERO_MASK));
    newCSR |= (_MM_ROUND_NEAREST | _MM_FLUSH_ZERO_ON | _MM_DENORMALS_ZERO_ON);
    _mm_setcsr(newCSR);

    return oldCSR;
}

/// Set Vector CSR state.
/// @param csrState - should be value returned from SetOptimalVectorCSR()
static INLINE void RestoreVectorCSR(uint32_t csrState)
{
    _mm_setcsr(csrState);
}

#endif //__SWR_OS_H__