gcc/libquadmath/quadmath-imp.h

/* GCC Quad-Precision Math Library
   Copyright (C) 2010, 2011 Free Software Foundation, Inc.
   Written by Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>

This file is part of the libquadmath library.
Libquadmath is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.

Libquadmath is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with libquadmath; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
Boston, MA 02110-1301, USA.  */

#ifndef QUADMATH_IMP_H
#define QUADMATH_IMP_H

#include <stdint.h>
#include <stdlib.h>
#include "quadmath.h"
#include "config.h"


/* Under IEEE 754, an architecture may determine tininess of
   floating-point results either "before rounding" or "after
   rounding", but must do so in the same way for all operations
   returning binary results.  Define TININESS_AFTER_ROUNDING to 1 for
   "after rounding" architectures, 0 for "before rounding"
   architectures.  */

#define TININESS_AFTER_ROUNDING   1


/* Prototypes for internal functions.  */
extern int32_t __quadmath_rem_pio2q (__float128, __float128 *);
extern void __quadmath_kernel_sincosq (__float128, __float128, __float128 *,
				       __float128 *, int);
extern __float128 __quadmath_kernel_sinq (__float128, __float128, int);
extern __float128 __quadmath_kernel_cosq (__float128, __float128);
extern __float128 __quadmath_x2y2m1q (__float128 x, __float128 y);
extern int __quadmath_isinf_nsq (__float128 x);





/* Frankly, if you have __float128, you have 64-bit integers, right?  */
#ifndef UINT64_C
# error "No way!"
#endif


/* Main union type we use to manipulate the floating-point type.  */
typedef union
{
  __float128 value;

  struct
#ifdef __MINGW32__
  /* On mingw targets the ms-bitfields option is active by default.
     Therefore enforce gnu-bitfield style.  */
  __attribute__ ((gcc_struct))
#endif
  {
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
    unsigned negative:1;
    unsigned exponent:15;
    uint64_t mant_high:48;
    uint64_t mant_low:64;
#else
    uint64_t mant_low:64;
    uint64_t mant_high:48;
    unsigned exponent:15;
    unsigned negative:1;
#endif
  } ieee;

  struct
  {
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
    uint64_t high;
    uint64_t low;
#else
    uint64_t low;
    uint64_t high;
#endif
  } words64;

  struct
  {
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
    uint32_t w0;
    uint32_t w1;
    uint32_t w2;
    uint32_t w3;
#else
    uint32_t w3;
    uint32_t w2;
    uint32_t w1;
    uint32_t w0;
#endif
  } words32;

  struct
#ifdef __MINGW32__
  /* Make sure we are using gnu-style bitfield handling.  */
  __attribute__ ((gcc_struct))
#endif
  {
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
    unsigned negative:1;
    unsigned exponent:15;
    unsigned quiet_nan:1;
    uint64_t mant_high:47;
    uint64_t mant_low:64;
#else
    uint64_t mant_low:64;
    uint64_t mant_high:47;
    unsigned quiet_nan:1;
    unsigned exponent:15;
    unsigned negative:1;
#endif
  } nan;

} ieee854_float128;


/* Get two 64 bit ints from a long double.  */
#define GET_FLT128_WORDS64(ix0,ix1,d)  \
do {                                   \
  ieee854_float128 u;                  \
  u.value = (d);                       \
  (ix0) = u.words64.high;              \
  (ix1) = u.words64.low;               \
} while (0)

/* Set a long double from two 64 bit ints.  */
#define SET_FLT128_WORDS64(d,ix0,ix1)  \
do {                                   \
  ieee854_float128 u;                  \
  u.words64.high = (ix0);              \
  u.words64.low = (ix1);               \
  (d) = u.value;                       \
} while (0)

/* Get the more significant 64 bits of a long double mantissa.  */
#define GET_FLT128_MSW64(v,d)          \
do {                                   \
  ieee854_float128 u;                  \
  u.value = (d);                       \
  (v) = u.words64.high;                \
} while (0)

/* Set the more significant 64 bits of a long double mantissa from an int.  */
#define SET_FLT128_MSW64(d,v)          \
do {                                   \
  ieee854_float128 u;                  \
  u.value = (d);                       \
  u.words64.high = (v);                \
  (d) = u.value;                       \
} while (0)

/* Get the least significant 64 bits of a long double mantissa.  */
#define GET_FLT128_LSW64(v,d)          \
do {                                   \
  ieee854_float128 u;                  \
  u.value = (d);                       \
  (v) = u.words64.low;                 \
} while (0)


#define IEEE854_FLOAT128_BIAS 0x3fff

#define QUADFP_NAN		0
#define QUADFP_INFINITE		1
#define QUADFP_ZERO		2
#define QUADFP_SUBNORMAL	3
#define QUADFP_NORMAL		4
#define fpclassifyq(x) \
  __builtin_fpclassify (QUADFP_NAN, QUADFP_INFINITE, QUADFP_NORMAL, \
			QUADFP_SUBNORMAL, QUADFP_ZERO, x)

#ifndef math_opt_barrier
# define math_opt_barrier(x) \
({ __typeof (x) __x = (x); __asm ("" : "+m" (__x)); __x; })
# define math_force_eval(x) \
({ __typeof (x) __x = (x); __asm __volatile__ ("" : : "m" (__x)); })
#endif

/* math_narrow_eval reduces its floating-point argument to the range
   and precision of its semantic type.  (The original evaluation may
   still occur with excess range and precision, so the result may be
   affected by double rounding.)  */
#define math_narrow_eval(x) (x)

/* If X (which is not a NaN) is subnormal, force an underflow
   exception.  */
#define math_check_force_underflow(x)				\
  do								\
    {								\
      __float128 force_underflow_tmp = (x);			\
      if (fabsq (force_underflow_tmp) < FLT128_MIN)		\
	{							\
	  __float128 force_underflow_tmp2			\
	    = force_underflow_tmp * force_underflow_tmp;	\
	  math_force_eval (force_underflow_tmp2);		\
	}							\
    }								\
  while (0)
/* Likewise, but X is also known to be nonnegative.  */
#define math_check_force_underflow_nonneg(x)			\
  do								\
    {								\
      __float128 force_underflow_tmp = (x);			\
      if (force_underflow_tmp < FLT128_MIN)			\
	{							\
	  __float128 force_underflow_tmp2			\
	    = force_underflow_tmp * force_underflow_tmp;	\
	  math_force_eval (force_underflow_tmp2);		\
	}							\
    }								\
  while (0)

#endif