//===-- lib/fp_lib.h - Floating-point utilities -------------------*- C -*-===//

//

//                     The LLVM Compiler Infrastructure

//

// This file is dual licensed under the MIT and the University of Illinois Open

// Source Licenses. See LICENSE.TXT for details.

//

//===----------------------------------------------------------------------===//

//

// This file is a configuration header for soft-float routines in compiler-rt.

// This file does not provide any part of the compiler-rt interface, but defines

// many useful constants and utility routines that are used in the

// implementation of the soft-float routines in compiler-rt.

//

// Assumes that float, double and long double correspond to the IEEE-754

// binary32, binary64 and binary 128 types, respectively, and that integer

// endianness matches floating point endianness on the target platform.

//

//===----------------------------------------------------------------------===//

#ifndef FP_LIB_HEADER

#define FP_LIB_HEADER

#include <stdint.h>

#include <stdbool.h>

#include <limits.h>

#include "int_lib.h"

// x86_64 FreeBSD prior v9.3 define fixed-width types incorrectly in

// 32-bit mode.

#if defined(__FreeBSD__) && defined(__i386__)

# include <sys/param.h>

# if __FreeBSD_version < 903000  // v9.3

#  define uint64_t unsigned long long

#  define int64_t long long

#  undef UINT64_C

#  define UINT64_C(c) (c ## ULL)

# endif

#endif

#if defined SINGLE_PRECISION

typedef uint32_t rep_t;

typedef int32_t srep_t;

typedef float fp_t;

#define REP_C UINT32_C

#define significandBits 23

static __inline int rep_clz(rep_t a) {

}

// 32x32 --> 64 bit multiply

static __inline void wideMultiply(rep_t a, rep_t b, rep_t *hi, rep_t *lo) {

}

COMPILER_RT_ABI fp_t __addsf3(fp_t a, fp_t b);

#elif defined DOUBLE_PRECISION

typedef uint64_t rep_t;

typedef int64_t srep_t;

typedef double fp_t;

#define REP_C UINT64_C

#define significandBits 52

static __inline int rep_clz(rep_t a) {

#if defined __LP64__

#else

    if (a & REP_C(0xffffffff00000000))

        return __builtin_clz(a >> 32);

    else

        return 32 + __builtin_clz(a & REP_C(0xffffffff));

#endif

}

#define loWord(a) (a & 0xffffffffU)

#define hiWord(a) (a >> 32)

// 64x64 -> 128 wide multiply for platforms that don't have such an operation;

// many 64-bit platforms have this operation, but they tend to have hardware

// floating-point, so we don't bother with a special case for them here.

static __inline void wideMultiply(rep_t a, rep_t b, rep_t *hi, rep_t *lo) {

    // Each of the component 32x32 -> 64 products

    // Sum terms that contribute to lo in a way that allows us to get the carry

    // Sum terms contributing to hi with the carry from lo

}

#undef loWord

#undef hiWord

COMPILER_RT_ABI fp_t __adddf3(fp_t a, fp_t b);

#elif defined QUAD_PRECISION

#if __LDBL_MANT_DIG__ == 113

#define CRT_LDBL_128BIT

typedef __uint128_t rep_t;

typedef __int128_t srep_t;

typedef long double fp_t;

#define REP_C (__uint128_t)

// Note: Since there is no explicit way to tell compiler the constant is a

// 128-bit integer, we let the constant be casted to 128-bit integer

#define significandBits 112

static __inline int rep_clz(rep_t a) {

    const union

        {

             __uint128_t ll;

#if _YUGA_BIG_ENDIAN

             struct { uint64_t high, low; } s;

#else

             struct { uint64_t low, high; } s;

#endif

        } uu = { .ll = a };

    uint64_t word;

    uint64_t add;

    if (uu.s.high){

        word = uu.s.high;

        add = 0;

    }

    else{

        word = uu.s.low;

        add = 64;

    }

    return __builtin_clzll(word) + add;

}

#define Word_LoMask   UINT64_C(0x00000000ffffffff)

#define Word_HiMask   UINT64_C(0xffffffff00000000)

#define Word_FullMask UINT64_C(0xffffffffffffffff)

#define Word_1(a) (uint64_t)((a >> 96) & Word_LoMask)

#define Word_2(a) (uint64_t)((a >> 64) & Word_LoMask)

#define Word_3(a) (uint64_t)((a >> 32) & Word_LoMask)

#define Word_4(a) (uint64_t)(a & Word_LoMask)

// 128x128 -> 256 wide multiply for platforms that don't have such an operation;

// many 64-bit platforms have this operation, but they tend to have hardware

// floating-point, so we don't bother with a special case for them here.

static __inline void wideMultiply(rep_t a, rep_t b, rep_t *hi, rep_t *lo) {

    const uint64_t product11 = Word_1(a) * Word_1(b);

    const uint64_t product12 = Word_1(a) * Word_2(b);

    const uint64_t product13 = Word_1(a) * Word_3(b);

    const uint64_t product14 = Word_1(a) * Word_4(b);

    const uint64_t product21 = Word_2(a) * Word_1(b);

    const uint64_t product22 = Word_2(a) * Word_2(b);

    const uint64_t product23 = Word_2(a) * Word_3(b);

    const uint64_t product24 = Word_2(a) * Word_4(b);

    const uint64_t product31 = Word_3(a) * Word_1(b);

    const uint64_t product32 = Word_3(a) * Word_2(b);

    const uint64_t product33 = Word_3(a) * Word_3(b);

    const uint64_t product34 = Word_3(a) * Word_4(b);

    const uint64_t product41 = Word_4(a) * Word_1(b);

    const uint64_t product42 = Word_4(a) * Word_2(b);

    const uint64_t product43 = Word_4(a) * Word_3(b);

    const uint64_t product44 = Word_4(a) * Word_4(b);

    const __uint128_t sum0 = (__uint128_t)product44;

    const __uint128_t sum1 = (__uint128_t)product34 +

                             (__uint128_t)product43;

    const __uint128_t sum2 = (__uint128_t)product24 +

                             (__uint128_t)product33 +

                             (__uint128_t)product42;

    const __uint128_t sum3 = (__uint128_t)product14 +

                             (__uint128_t)product23 +

                             (__uint128_t)product32 +

                             (__uint128_t)product41;

    const __uint128_t sum4 = (__uint128_t)product13 +

                             (__uint128_t)product22 +

                             (__uint128_t)product31;

    const __uint128_t sum5 = (__uint128_t)product12 +

                             (__uint128_t)product21;

    const __uint128_t sum6 = (__uint128_t)product11;

    const __uint128_t r0 = (sum0 & Word_FullMask) +

                           ((sum1 & Word_LoMask) << 32);

    const __uint128_t r1 = (sum0 >> 64) +

                           ((sum1 >> 32) & Word_FullMask) +

                           (sum2 & Word_FullMask) +

                           ((sum3 << 32) & Word_HiMask);

    *lo = r0 + (r1 << 64);

    *hi = (r1 >> 64) +

          (sum1 >> 96) +

          (sum2 >> 64) +

          (sum3 >> 32) +

          sum4 +

          (sum5 << 32) +

          (sum6 << 64);

}

#undef Word_1

#undef Word_2

#undef Word_3

#undef Word_4

#undef Word_HiMask

#undef Word_LoMask

#undef Word_FullMask

#endif // __LDBL_MANT_DIG__ == 113

#else

#error SINGLE_PRECISION, DOUBLE_PRECISION or QUAD_PRECISION must be defined.

#endif

#if defined(SINGLE_PRECISION) || defined(DOUBLE_PRECISION) || defined(CRT_LDBL_128BIT)

#define typeWidth       (sizeof(rep_t)*CHAR_BIT)

#define exponentBits    (typeWidth - significandBits - 1)

#define maxExponent     ((1 << exponentBits) - 1)

#define exponentBias    (maxExponent >> 1)

#define implicitBit     (REP_C(1) << significandBits)

#define significandMask (implicitBit - 1U)

#define signBit         (REP_C(1) << (significandBits + exponentBits))

#define absMask         (signBit - 1U)

#define exponentMask    (absMask ^ significandMask)

#define oneRep          ((rep_t)exponentBias << significandBits)

#define infRep          exponentMask

#define quietBit        (implicitBit >> 1)

#define qnanRep         (exponentMask | quietBit)

static __inline rep_t toRep(fp_t x) {

}

static __inline fp_t fromRep(rep_t x) {

    const union { fp_t f; rep_t i; } rep = {.i = x};

}

static __inline int normalize(rep_t *significand) {

}

static __inline void wideLeftShift(rep_t *hi, rep_t *lo, int count) {

}

static __inline void wideRightShiftWithSticky(rep_t *hi, rep_t *lo, unsigned int count) {

    }

    }

}

#endif

#endif // FP_LIB_HEADER