toolchain/gcc/newlib/libc/machine/powerpc/ufix64toa.c

   1 /* _ufix64toa_r: convert unsigned 64-bit fixed point to ASCII string.
   2  *
   3  * This routine converts an unsigned fixed-point number to long double format and
   4  * then calls _ldtoa_r to do the conversion.
   5  *
   6  * Written by Jeff Johnston.
   7  */
   8
   9 #ifdef __SPE__
  10
  11 #include <_ansi.h>
  12 #include <limits.h>
  13 #include <errno.h>
  14 #include <stdlib.h>
  15 #include <reent.h>
  16 #include "fix64.h"
  17
  18 extern char *_simdldtoa_r _PARAMS((struct _reent *, LONG_DOUBLE_UNION *, int,
  19                                int, int *, int *, char **));
  20
  21 /*
  22  * Convert an unsigned fixed-point 64-bit value to string.
  23  *
  24  * Ignores `locale' stuff.
  25  */
  26
  27 char *
  28 _DEFUN (_ufix64toa_r, (rptr, value, mode, ndigits, decpt, sign, rve),
  29         struct _reent *rptr _AND
  30         __uint64_t value _AND
  31         int mode _AND
  32         int ndigits _AND
  33         int *decpt _AND
  34         int *sign _AND
  35         char **rve)
  36 {
  37   union long_double_union ldbl;
  38   union fix64_union fix64;
  39   unsigned long tmp;
  40   int exp, negexp;
  41
  42   /* if input is 0, no additional work is needed */
  43   if (value == 0)
  44     {
  45       ldbl.i[0] = ldbl.i[1] = ldbl.i[2] = ldbl.i[3] = 0;
  46     }
  47   else /* otherwise, we calculate long double equivalent of value */
  48     {
  49       /* find exponent by locating most-significant one-bit */
  50       fix64.ll = value;
  51       negexp = 1;
  52       if (hiword(fix64) == 0)
  53         {
  54           tmp = loword(fix64);
  55           negexp = 33;
  56         }
  57       else
  58         {
  59           tmp = hiword(fix64);
  60           negexp = 1;
  61         }
  62
  63       while (negexp < 65)
  64         {
  65           if (tmp & 0x80000000)
  66             break;
  67           ++negexp;
  68           tmp <<= 1;
  69         }
  70
  71       /* shift input appropriately */
  72       fix64.ll = value << (negexp - 1 + (Exp_msk1 != 0));
  73
  74       /* build long double */
  75       exp = -negexp + Bias;
  76       word0(ldbl) = (exp << Exp_shift);
  77       word1(ldbl) = hiword(fix64) << (32-Ebits-1);
  78       word2(ldbl) = loword(fix64) << (32-Ebits-1);
  79       word3(ldbl) = 0;
  80       if (Ebits+1 < 32)
  81         {
  82           word0(ldbl) |= hiword(fix64) >> (Ebits + 1);
  83           word1(ldbl) |= loword(fix64) >> (Ebits + 1);
  84         }
  85     }
  86
  87   /* convert long double to character */
  88   return _simdldtoa_r (rptr, &ldbl, mode, ndigits, decpt, sign, rve);
  89 }
  90
  91 #endif /* __SPE__ */