1  /* Print floating point number in hexadecimal notation according to ISO C99.
       2     Copyright (C) 1997-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #define PRINT_FPHEX_LONG_DOUBLE \
      20  do {									      \
      21        /* We have 105 bits of mantissa plus one implicit digit.  Since	      \
      22  	 106 bits are representable without rest using hexadecimal	      \
      23  	 digits we use only the implicit digits for the number before	      \
      24  	 the decimal point.  */						      \
      25        unsigned long long int num0, num1;				      \
      26        unsigned long long hi, lo;					      \
      27        int ediff;							      \
      28        union ibm_extended_long_double u;					      \
      29        u.ld = fpnum.ldbl;						      \
      30  									      \
      31        assert (sizeof (long double) == 16);				      \
      32  									      \
      33        lo = ((long long)u.d[1].ieee.mantissa0 << 32) | u.d[1].ieee.mantissa1;  \
      34        hi = ((long long)u.d[0].ieee.mantissa0 << 32) | u.d[0].ieee.mantissa1;  \
      35        lo <<= 7; /* pre-shift lo to match ieee854.  */			      \
      36        /* If the lower double is not a denormal or zero then set the hidden    \
      37  	 53rd bit.  */							      \
      38        if (u.d[1].ieee.exponent != 0)					      \
      39  	lo |= (1ULL << (52 + 7));					      \
      40        else								      \
      41  	lo <<= 1;							      \
      42        /* The lower double is normalized separately from the upper.  We	      \
      43  	 may need to adjust the lower manitissa to reflect this.  */	      \
      44        ediff = u.d[0].ieee.exponent - u.d[1].ieee.exponent - 53;		      \
      45        if (ediff > 63)							      \
      46  	lo = 0;								      \
      47        else if (ediff > 0)						      \
      48  	lo = lo >> ediff;						      \
      49        else if (ediff < 0)						      \
      50  	lo = lo << -ediff;						      \
      51        if (u.d[0].ieee.negative != u.d[1].ieee.negative			      \
      52  	  && lo != 0)							      \
      53  	{								      \
      54  	  lo = (1ULL << 60) - lo;					      \
      55  	  if (hi == 0L)							      \
      56  	    {								      \
      57  	      /* we have a borrow from the hidden bit, so shift left 1.  */   \
      58  	      hi = 0xffffffffffffeLL | (lo >> 59);			      \
      59  	      lo = 0xfffffffffffffffLL & (lo << 1);			      \
      60  	      u.d[0].ieee.exponent--;					      \
      61  	    }								      \
      62  	  else								      \
      63  	    hi--;							      \
      64          }								      \
      65        num1 = (hi << 60) | lo;						      \
      66        num0 = hi >> 4;							      \
      67  									      \
      68        zero_mantissa = (num0|num1) == 0;					      \
      69  									      \
      70        if (sizeof (unsigned long int) > 6)				      \
      71  	numstr = _itoa_word (num1, numbuf + sizeof numbuf, 16,		      \
      72  			     info->spec == 'A');			      \
      73        else								      \
      74  	numstr = _itoa (num1, numbuf + sizeof numbuf, 16,		      \
      75  			  info->spec == 'A');				      \
      76  									      \
      77        while (numstr > numbuf + (sizeof numbuf - 64 / 4))		      \
      78  	*--numstr = '0';						      \
      79  									      \
      80        if (sizeof (unsigned long int) > 6)				      \
      81  	numstr = _itoa_word (num0, numstr, 16, info->spec == 'A');	      \
      82        else								      \
      83  	numstr = _itoa (num0, numstr, 16, info->spec == 'A');		      \
      84  									      \
      85        /* Fill with zeroes.  */						      \
      86        while (numstr > numbuf + (sizeof numbuf - 112 / 4))		      \
      87  	*--numstr = '0';						      \
      88  									      \
      89        leading = u.d[0].ieee.exponent == 0 ? '0' : '1';			      \
      90  									      \
      91        exponent = u.d[0].ieee.exponent;					      \
      92  									      \
      93        if (exponent == 0)						      \
      94  	{								      \
      95  	  if (zero_mantissa)						      \
      96  	    expnegative = 0;						      \
      97  	  else								      \
      98  	    {								      \
      99  	      /* This is a denormalized number.  */			      \
     100  	      expnegative = 1;						      \
     101  	      exponent = IEEE754_DOUBLE_BIAS - 1;			      \
     102  	    }								      \
     103  	}								      \
     104        else if (exponent >= IEEE754_DOUBLE_BIAS)				      \
     105  	{								      \
     106  	  expnegative = 0;						      \
     107  	  exponent -= IEEE754_DOUBLE_BIAS;				      \
     108  	}								      \
     109        else								      \
     110  	{								      \
     111  	  expnegative = 1;						      \
     112  	  exponent = -(exponent - IEEE754_DOUBLE_BIAS);			      \
     113  	}								      \
     114  } while (0)
     115  
     116  #include <stdio-common/printf_fphex.c>