#pragma once

#include <emmintrin.h>

#if defined(_MSC_VER) && _MSC_VER <= 1800
#define thread_local __declspec(thread)
#elif __APPLE__
#define thread_local __thread
#endif

#if defined(_MSC_VER)
#define never_inline __declspec(noinline)
#else
#define never_inline __attribute__((noinline))
#endif

#if defined(_MSC_VER)
#define safe_buffers __declspec(safebuffers)
#else
#define safe_buffers
#endif

#if defined(_MSC_VER)
#define force_inline __forceinline
#else
#define force_inline __attribute__((always_inline)) inline
#endif

#if defined(_MSC_VER) && _MSC_VER <= 1800
#define alignas(x) _CRT_ALIGN(x)
#endif

#if defined(__GNUG__)

#include <stdlib.h>
#include <cstdint>

#define _fpclass(x) std::fpclassify(x)
#define INFINITE 0xFFFFFFFF

#ifdef __APPLE__

// XXX only supports a single timer
#define TIMER_ABSTIME -1
/* The opengroup spec isn't clear on the mapping from REALTIME to CALENDAR
 being appropriate or not.
 http://pubs.opengroup.org/onlinepubs/009695299/basedefs/time.h.html */
#define CLOCK_REALTIME  1 // #define CALENDAR_CLOCK 1 from mach/clock_types.h
#define CLOCK_MONOTONIC 0 // #define SYSTEM_CLOCK 0

typedef int clockid_t;

/* the mach kernel uses struct mach_timespec, so struct timespec
    is loaded from <sys/_types/_timespec.h> for compatability */
// struct timespec { time_t tv_sec; long tv_nsec; };

int clock_gettime(clockid_t clk_id, struct timespec *tp);

#endif /* __APPLE__ */
#endif /* __GNUG__ */

#if defined(_MSC_VER)

// Unsigned 128-bit integer implementation
struct alignas(16) u128
{
	std::uint64_t lo, hi;

	u128() = default;

	u128(const u128&) = default;

	u128(std::uint64_t l)
		: lo(l)
		, hi(0)
	{
	}

	u128 operator +(const u128& r) const
	{
		u128 value;
		_addcarry_u64(_addcarry_u64(0, r.lo, lo, &value.lo), r.hi, hi, &value.hi);
		return value;
	}

	friend u128 operator +(const u128& l, std::uint64_t r)
	{
		u128 value;
		_addcarry_u64(_addcarry_u64(0, r, l.lo, &value.lo), l.hi, 0, &value.hi);
		return value;
	}

	friend u128 operator +(std::uint64_t l, const u128& r)
	{
		u128 value;
		_addcarry_u64(_addcarry_u64(0, r.lo, l, &value.lo), 0, r.hi, &value.hi);
		return value;
	}

	u128 operator -(const u128& r) const
	{
		u128 value;
		_subborrow_u64(_subborrow_u64(0, r.lo, lo, &value.lo), r.hi, hi, &value.hi);
		return value;
	}

	friend u128 operator -(const u128& l, std::uint64_t r)
	{
		u128 value;
		_subborrow_u64(_subborrow_u64(0, r, l.lo, &value.lo), 0, l.hi, &value.hi);
		return value;
	}

	friend u128 operator -(std::uint64_t l, const u128& r)
	{
		u128 value;
		_subborrow_u64(_subborrow_u64(0, r.lo, l, &value.lo), r.hi, 0, &value.hi);
		return value;
	}

	u128 operator +() const
	{
		return *this;
	}

	u128 operator -() const
	{
		u128 value;
		_subborrow_u64(_subborrow_u64(0, lo, 0, &value.lo), hi, 0, &value.hi);
		return value;
	}

	u128& operator ++()
	{
		_addcarry_u64(_addcarry_u64(0, 1, lo, &lo), 0, hi, &hi);
		return *this;
	}

	u128 operator ++(int)
	{
		u128 value = *this;
		_addcarry_u64(_addcarry_u64(0, 1, lo, &lo), 0, hi, &hi);
		return value;
	}

	u128& operator --()
	{
		_subborrow_u64(_subborrow_u64(0, 1, lo, &lo), 0, hi, &hi);
		return *this;
	}

	u128 operator --(int)
	{
		u128 value = *this;
		_subborrow_u64(_subborrow_u64(0, 1, lo, &lo), 0, hi, &hi);
		return value;
	}

	u128 operator ~() const
	{
		u128 value;
		value.lo = ~lo;
		value.hi = ~hi;
		return value;
	}

	u128 operator &(const u128& r) const
	{
		u128 value;
		value.lo = lo & r.lo;
		value.hi = hi & r.hi;
		return value;
	}

	u128 operator |(const u128& r) const
	{
		u128 value;
		value.lo = lo | r.lo;
		value.hi = hi | r.hi;
		return value;
	}

	u128 operator ^(const u128& r) const
	{
		u128 value;
		value.lo = lo ^ r.lo;
		value.hi = hi ^ r.hi;
		return value;
	}

	u128& operator +=(const u128& r)
	{
		_addcarry_u64(_addcarry_u64(0, r.lo, lo, &lo), r.hi, hi, &hi);
		return *this;
	}

	u128& operator +=(uint64_t r)
	{
		_addcarry_u64(_addcarry_u64(0, r, lo, &lo), 0, hi, &hi);
		return *this;
	}

	u128& operator &=(const u128& r)
	{
		lo &= r.lo;
		hi &= r.hi;
		return *this;
	}

	u128& operator |=(const u128& r)
	{
		lo |= r.lo;
		hi |= r.hi;
		return *this;
	}

	u128& operator ^=(const u128& r)
	{
		lo ^= r.lo;
		hi ^= r.hi;
		return *this;
	}
};
#endif

inline std::uint32_t cntlz32(std::uint32_t arg)
{
#if defined(_MSC_VER)
	unsigned long res;
	return _BitScanReverse(&res, arg) ? res ^ 31 : 32;
#else
	return arg ? __builtin_clzll(arg) - 32 : 32;
#endif
}

inline std::uint64_t cntlz64(std::uint64_t arg)
{
#if defined(_MSC_VER)
	unsigned long res;
	return _BitScanReverse64(&res, arg) ? res ^ 63 : 64;
#else
	return arg ? __builtin_clzll(arg) : 64;
#endif
}

// compare 16 packed unsigned bytes (greater than)
inline __m128i sse_cmpgt_epu8(__m128i A, __m128i B)
{
	// (A xor 0x80) > (B xor 0x80)
	const auto sign = _mm_set1_epi32(0x80808080);
	return _mm_cmpgt_epi8(_mm_xor_si128(A, sign), _mm_xor_si128(B, sign));
}

inline __m128i sse_cmpgt_epu16(__m128i A, __m128i B)
{
	const auto sign = _mm_set1_epi32(0x80008000);
	return _mm_cmpgt_epi16(_mm_xor_si128(A, sign), _mm_xor_si128(B, sign));
}

inline __m128i sse_cmpgt_epu32(__m128i A, __m128i B)
{
	const auto sign = _mm_set1_epi32(0x80000000);
	return _mm_cmpgt_epi32(_mm_xor_si128(A, sign), _mm_xor_si128(B, sign));
}

inline __m128 sse_exp2_ps(__m128 A)
{
	const auto x0 = _mm_max_ps(_mm_min_ps(A, _mm_set1_ps(127.4999961f)), _mm_set1_ps(-127.4999961f));
	const auto x1 = _mm_add_ps(x0, _mm_set1_ps(0.5f));
	const auto x2 = _mm_sub_epi32(_mm_cvtps_epi32(x1), _mm_and_si128(_mm_castps_si128(_mm_cmpnlt_ps(_mm_setzero_ps(), x1)), _mm_set1_epi32(1)));
	const auto x3 = _mm_sub_ps(x0, _mm_cvtepi32_ps(x2));
	const auto x4 = _mm_mul_ps(x3, x3);
	const auto x5 = _mm_mul_ps(x3, _mm_add_ps(_mm_mul_ps(_mm_add_ps(_mm_mul_ps(x4, _mm_set1_ps(0.023093347705f)), _mm_set1_ps(20.20206567f)), x4), _mm_set1_ps(1513.906801f)));
	const auto x6 = _mm_mul_ps(x5, _mm_rcp_ps(_mm_sub_ps(_mm_add_ps(_mm_mul_ps(_mm_set1_ps(233.1842117f), x4), _mm_set1_ps(4368.211667f)), x5)));
	return _mm_mul_ps(_mm_add_ps(_mm_add_ps(x6, x6), _mm_set1_ps(1.0f)), _mm_castsi128_ps(_mm_slli_epi32(_mm_add_epi32(x2, _mm_set1_epi32(127)), 23)));
}

inline __m128 sse_log2_ps(__m128 A)
{
	const auto _1 = _mm_set1_ps(1.0f);
	const auto _c = _mm_set1_ps(1.442695040f);
	const auto x0 = _mm_max_ps(A, _mm_castsi128_ps(_mm_set1_epi32(0x00800000)));
	const auto x1 = _mm_or_ps(_mm_and_ps(x0, _mm_castsi128_ps(_mm_set1_epi32(0x807fffff))), _1);
	const auto x2 = _mm_rcp_ps(_mm_add_ps(x1, _1));
	const auto x3 = _mm_mul_ps(_mm_sub_ps(x1, _1), x2);
	const auto x4 = _mm_add_ps(x3, x3);
	const auto x5 = _mm_mul_ps(x4, x4);
	const auto x6 = _mm_add_ps(_mm_mul_ps(_mm_add_ps(_mm_mul_ps(_mm_set1_ps(-0.7895802789f), x5), _mm_set1_ps(16.38666457f)), x5), _mm_set1_ps(-64.1409953f));
	const auto x7 = _mm_rcp_ps(_mm_add_ps(_mm_mul_ps(_mm_add_ps(_mm_mul_ps(_mm_set1_ps(-35.67227983f), x5), _mm_set1_ps(312.0937664f)), x5), _mm_set1_ps(-769.6919436f)));
	const auto x8 = _mm_cvtepi32_ps(_mm_sub_epi32(_mm_srli_epi32(_mm_castps_si128(x0), 23), _mm_set1_epi32(127)));
	return _mm_add_ps(_mm_mul_ps(_mm_mul_ps(_mm_mul_ps(_mm_mul_ps(x5, x6), x7), x4), _c), _mm_add_ps(_mm_mul_ps(x4, _c), x8));
}