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-rw-r--r--REORG.TODO/stdio-common/printf_fp.c1364
1 files changed, 1364 insertions, 0 deletions
diff --git a/REORG.TODO/stdio-common/printf_fp.c b/REORG.TODO/stdio-common/printf_fp.c
new file mode 100644
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+++ b/REORG.TODO/stdio-common/printf_fp.c
@@ -0,0 +1,1364 @@
+/* Floating point output for `printf'.
+   Copyright (C) 1995-2017 Free Software Foundation, Inc.
+
+   This file is part of the GNU C Library.
+   Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* The gmp headers need some configuration frobs.  */
+#define HAVE_ALLOCA 1
+
+#include <libioP.h>
+#include <alloca.h>
+#include <ctype.h>
+#include <float.h>
+#include <gmp-mparam.h>
+#include <gmp.h>
+#include <ieee754.h>
+#include <stdlib/gmp-impl.h>
+#include <stdlib/longlong.h>
+#include <stdlib/fpioconst.h>
+#include <locale/localeinfo.h>
+#include <limits.h>
+#include <math.h>
+#include <printf.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <wchar.h>
+#include <stdbool.h>
+#include <rounding-mode.h>
+
+#ifdef COMPILE_WPRINTF
+# define CHAR_T        wchar_t
+#else
+# define CHAR_T        char
+#endif
+
+#include "_i18n_number.h"
+
+#ifndef NDEBUG
+# define NDEBUG			/* Undefine this for debugging assertions.  */
+#endif
+#include <assert.h>
+
+/* This defines make it possible to use the same code for GNU C library and
+   the GNU I/O library.	 */
+#define PUT(f, s, n) _IO_sputn (f, s, n)
+#define PAD(f, c, n) (wide ? _IO_wpadn (f, c, n) : _IO_padn (f, c, n))
+/* We use this file GNU C library and GNU I/O library.	So make
+   names equal.	 */
+#undef putc
+#define putc(c, f) (wide \
+		    ? (int)_IO_putwc_unlocked (c, f) : _IO_putc_unlocked (c, f))
+#define size_t     _IO_size_t
+#define FILE	     _IO_FILE
+
+/* Macros for doing the actual output.  */
+
+#define outchar(ch)							      \
+  do									      \
+    {									      \
+      const int outc = (ch);						      \
+      if (putc (outc, fp) == EOF)					      \
+	{								      \
+	  if (buffer_malloced)						      \
+	    free (wbuffer);						      \
+	  return -1;							      \
+	}								      \
+      ++done;								      \
+    } while (0)
+
+#define PRINT(ptr, wptr, len)						      \
+  do									      \
+    {									      \
+      size_t outlen = (len);						      \
+      if (len > 20)							      \
+	{								      \
+	  if (PUT (fp, wide ? (const char *) wptr : ptr, outlen) != outlen)   \
+	    {								      \
+	      if (buffer_malloced)					      \
+		free (wbuffer);						      \
+	      return -1;						      \
+	    }								      \
+	  ptr += outlen;						      \
+	  done += outlen;						      \
+	}								      \
+      else								      \
+	{								      \
+	  if (wide)							      \
+	    while (outlen-- > 0)					      \
+	      outchar (*wptr++);					      \
+	  else								      \
+	    while (outlen-- > 0)					      \
+	      outchar (*ptr++);						      \
+	}								      \
+    } while (0)
+
+#define PADN(ch, len)							      \
+  do									      \
+    {									      \
+      if (PAD (fp, ch, len) != len)					      \
+	{								      \
+	  if (buffer_malloced)						      \
+	    free (wbuffer);						      \
+	  return -1;							      \
+	}								      \
+      done += len;							      \
+    }									      \
+  while (0)
+
+/* We use the GNU MP library to handle large numbers.
+
+   An MP variable occupies a varying number of entries in its array.  We keep
+   track of this number for efficiency reasons.  Otherwise we would always
+   have to process the whole array.  */
+#define MPN_VAR(name) mp_limb_t *name; mp_size_t name##size
+
+#define MPN_ASSIGN(dst,src)						      \
+  memcpy (dst, src, (dst##size = src##size) * sizeof (mp_limb_t))
+#define MPN_GE(u,v) \
+  (u##size > v##size || (u##size == v##size && __mpn_cmp (u, v, u##size) >= 0))
+
+extern mp_size_t __mpn_extract_double (mp_ptr res_ptr, mp_size_t size,
+				       int *expt, int *is_neg,
+				       double value);
+extern mp_size_t __mpn_extract_long_double (mp_ptr res_ptr, mp_size_t size,
+					    int *expt, int *is_neg,
+					    long double value);
+extern unsigned int __guess_grouping (unsigned int intdig_max,
+				      const char *grouping);
+
+
+static wchar_t *group_number (wchar_t *buf, wchar_t *bufend,
+			      unsigned int intdig_no, const char *grouping,
+			      wchar_t thousands_sep, int ngroups)
+     internal_function;
+
+struct hack_digit_param
+{
+  /* Sign of the exponent.  */
+  int expsign;
+  /* The type of output format that will be used: 'e'/'E' or 'f'.  */
+  int type;
+  /* and the exponent.	*/
+  int exponent;
+  /* The fraction of the floting-point value in question  */
+  MPN_VAR(frac);
+  /* Scaling factor.  */
+  MPN_VAR(scale);
+  /* Temporary bignum value.  */
+  MPN_VAR(tmp);
+};
+
+static wchar_t
+hack_digit (struct hack_digit_param *p)
+{
+  mp_limb_t hi;
+
+  if (p->expsign != 0 && p->type == 'f' && p->exponent-- > 0)
+    hi = 0;
+  else if (p->scalesize == 0)
+    {
+      hi = p->frac[p->fracsize - 1];
+      p->frac[p->fracsize - 1] = __mpn_mul_1 (p->frac, p->frac,
+	p->fracsize - 1, 10);
+    }
+  else
+    {
+      if (p->fracsize < p->scalesize)
+	hi = 0;
+      else
+	{
+	  hi = mpn_divmod (p->tmp, p->frac, p->fracsize,
+	    p->scale, p->scalesize);
+	  p->tmp[p->fracsize - p->scalesize] = hi;
+	  hi = p->tmp[0];
+
+	  p->fracsize = p->scalesize;
+	  while (p->fracsize != 0 && p->frac[p->fracsize - 1] == 0)
+	    --p->fracsize;
+	  if (p->fracsize == 0)
+	    {
+	      /* We're not prepared for an mpn variable with zero
+		 limbs.  */
+	      p->fracsize = 1;
+	      return L'0' + hi;
+	    }
+	}
+
+      mp_limb_t _cy = __mpn_mul_1 (p->frac, p->frac, p->fracsize, 10);
+      if (_cy != 0)
+	p->frac[p->fracsize++] = _cy;
+    }
+
+  return L'0' + hi;
+}
+
+int
+__printf_fp_l (FILE *fp, locale_t loc,
+	       const struct printf_info *info,
+	       const void *const *args)
+{
+  /* The floating-point value to output.  */
+  union
+    {
+      double dbl;
+      __long_double_t ldbl;
+#if __HAVE_DISTINCT_FLOAT128
+      _Float128 f128;
+#endif
+    }
+  fpnum;
+
+  /* Locale-dependent representation of decimal point.	*/
+  const char *decimal;
+  wchar_t decimalwc;
+
+  /* Locale-dependent thousands separator and grouping specification.  */
+  const char *thousands_sep = NULL;
+  wchar_t thousands_sepwc = 0;
+  const char *grouping;
+
+  /* "NaN" or "Inf" for the special cases.  */
+  const char *special = NULL;
+  const wchar_t *wspecial = NULL;
+
+  /* When _Float128 is enabled in the library and ABI-distinct from long
+     double, we need mp_limbs enough for any of them.  */
+#if __HAVE_DISTINCT_FLOAT128
+# define GREATER_MANT_DIG FLT128_MANT_DIG
+#else
+# define GREATER_MANT_DIG LDBL_MANT_DIG
+#endif
+  /* We need just a few limbs for the input before shifting to the right
+     position.	*/
+  mp_limb_t fp_input[(GREATER_MANT_DIG + BITS_PER_MP_LIMB - 1)
+		     / BITS_PER_MP_LIMB];
+  /* We need to shift the contents of fp_input by this amount of bits.	*/
+  int to_shift = 0;
+
+  struct hack_digit_param p;
+  /* Sign of float number.  */
+  int is_neg = 0;
+
+  /* Counter for number of written characters.	*/
+  int done = 0;
+
+  /* General helper (carry limb).  */
+  mp_limb_t cy;
+
+  /* Nonzero if this is output on a wide character stream.  */
+  int wide = info->wide;
+
+  /* Buffer in which we produce the output.  */
+  wchar_t *wbuffer = NULL;
+  /* Flag whether wbuffer is malloc'ed or not.  */
+  int buffer_malloced = 0;
+
+  p.expsign = 0;
+
+  /* Figure out the decimal point character.  */
+  if (info->extra == 0)
+    {
+      decimal = _nl_lookup (loc, LC_NUMERIC, DECIMAL_POINT);
+      decimalwc = _nl_lookup_word
+	(loc, LC_NUMERIC, _NL_NUMERIC_DECIMAL_POINT_WC);
+    }
+  else
+    {
+      decimal = _nl_lookup (loc, LC_MONETARY, MON_DECIMAL_POINT);
+      if (*decimal == '\0')
+	decimal = _nl_lookup (loc, LC_NUMERIC, DECIMAL_POINT);
+      decimalwc = _nl_lookup_word (loc, LC_MONETARY,
+				    _NL_MONETARY_DECIMAL_POINT_WC);
+      if (decimalwc == L'\0')
+	decimalwc = _nl_lookup_word (loc, LC_NUMERIC,
+				      _NL_NUMERIC_DECIMAL_POINT_WC);
+    }
+  /* The decimal point character must not be zero.  */
+  assert (*decimal != '\0');
+  assert (decimalwc != L'\0');
+
+  if (info->group)
+    {
+      if (info->extra == 0)
+	grouping = _nl_lookup (loc, LC_NUMERIC, GROUPING);
+      else
+	grouping = _nl_lookup (loc, LC_MONETARY, MON_GROUPING);
+
+      if (*grouping <= 0 || *grouping == CHAR_MAX)
+	grouping = NULL;
+      else
+	{
+	  /* Figure out the thousands separator character.  */
+	  if (wide)
+	    {
+	      if (info->extra == 0)
+		thousands_sepwc = _nl_lookup_word
+		  (loc, LC_NUMERIC, _NL_NUMERIC_THOUSANDS_SEP_WC);
+	      else
+		thousands_sepwc =
+		  _nl_lookup_word (loc, LC_MONETARY,
+				    _NL_MONETARY_THOUSANDS_SEP_WC);
+	    }
+	  else
+	    {
+	      if (info->extra == 0)
+		thousands_sep = _nl_lookup (loc, LC_NUMERIC, THOUSANDS_SEP);
+	      else
+		thousands_sep = _nl_lookup
+		  (loc, LC_MONETARY, MON_THOUSANDS_SEP);
+	    }
+
+	  if ((wide && thousands_sepwc == L'\0')
+	      || (! wide && *thousands_sep == '\0'))
+	    grouping = NULL;
+	  else if (thousands_sepwc == L'\0')
+	    /* If we are printing multibyte characters and there is a
+	       multibyte representation for the thousands separator,
+	       we must ensure the wide character thousands separator
+	       is available, even if it is fake.  */
+	    thousands_sepwc = 0xfffffffe;
+	}
+    }
+  else
+    grouping = NULL;
+
+#define PRINTF_FP_FETCH(FLOAT, VAR, SUFFIX, MANT_DIG)			\
+  {									\
+    (VAR) = *(const FLOAT *) args[0];					\
+									\
+    /* Check for special values: not a number or infinity.  */		\
+    if (isnan (VAR))							\
+      {									\
+	is_neg = signbit (VAR);						\
+	if (isupper (info->spec))					\
+	  {								\
+	    special = "NAN";						\
+	    wspecial = L"NAN";						\
+	  }								\
+	else								\
+	  {								\
+	    special = "nan";						\
+	    wspecial = L"nan";						\
+	  }								\
+      }									\
+    else if (isinf (VAR))						\
+      {									\
+	is_neg = signbit (VAR);						\
+	if (isupper (info->spec))					\
+	  {								\
+	    special = "INF";						\
+	    wspecial = L"INF";						\
+	  }								\
+	else								\
+	  {								\
+	    special = "inf";						\
+	    wspecial = L"inf";						\
+	  }								\
+      }									\
+    else								\
+      {									\
+	p.fracsize = __mpn_extract_##SUFFIX				\
+		     (fp_input,						\
+		      (sizeof (fp_input) / sizeof (fp_input[0])),	\
+		      &p.exponent, &is_neg, VAR);			\
+	to_shift = 1 + p.fracsize * BITS_PER_MP_LIMB - MANT_DIG;	\
+      }									\
+  }
+
+  /* Fetch the argument value.	*/
+#if __HAVE_DISTINCT_FLOAT128
+  if (info->is_binary128)
+    PRINTF_FP_FETCH (_Float128, fpnum.f128, float128, FLT128_MANT_DIG)
+  else
+#endif
+#ifndef __NO_LONG_DOUBLE_MATH
+  if (info->is_long_double && sizeof (long double) > sizeof (double))
+    PRINTF_FP_FETCH (long double, fpnum.ldbl, long_double, LDBL_MANT_DIG)
+  else
+#endif
+    PRINTF_FP_FETCH (double, fpnum.dbl, double, DBL_MANT_DIG)
+
+#undef PRINTF_FP_FETCH
+
+  if (special)
+    {
+      int width = info->width;
+
+      if (is_neg || info->showsign || info->space)
+	--width;
+      width -= 3;
+
+      if (!info->left && width > 0)
+	PADN (' ', width);
+
+      if (is_neg)
+	outchar ('-');
+      else if (info->showsign)
+	outchar ('+');
+      else if (info->space)
+	outchar (' ');
+
+      PRINT (special, wspecial, 3);
+
+      if (info->left && width > 0)
+	PADN (' ', width);
+
+      return done;
+    }
+
+
+  /* We need three multiprecision variables.  Now that we have the p.exponent
+     of the number we can allocate the needed memory.  It would be more
+     efficient to use variables of the fixed maximum size but because this
+     would be really big it could lead to memory problems.  */
+  {
+    mp_size_t bignum_size = ((abs (p.exponent) + BITS_PER_MP_LIMB - 1)
+			     / BITS_PER_MP_LIMB
+			     + (GREATER_MANT_DIG / BITS_PER_MP_LIMB > 2
+				? 8 : 4))
+			    * sizeof (mp_limb_t);
+    p.frac = (mp_limb_t *) alloca (bignum_size);
+    p.tmp = (mp_limb_t *) alloca (bignum_size);
+    p.scale = (mp_limb_t *) alloca (bignum_size);
+  }
+
+  /* We now have to distinguish between numbers with positive and negative
+     exponents because the method used for the one is not applicable/efficient
+     for the other.  */
+  p.scalesize = 0;
+  if (p.exponent > 2)
+    {
+      /* |FP| >= 8.0.  */
+      int scaleexpo = 0;
+      int explog;
+#if __HAVE_DISTINCT_FLOAT128
+      if (info->is_binary128)
+	explog = FLT128_MAX_10_EXP_LOG;
+      else
+	explog = LDBL_MAX_10_EXP_LOG;
+#else
+      explog = LDBL_MAX_10_EXP_LOG;
+#endif
+      int exp10 = 0;
+      const struct mp_power *powers = &_fpioconst_pow10[explog + 1];
+      int cnt_h, cnt_l, i;
+
+      if ((p.exponent + to_shift) % BITS_PER_MP_LIMB == 0)
+	{
+	  MPN_COPY_DECR (p.frac + (p.exponent + to_shift) / BITS_PER_MP_LIMB,
+			 fp_input, p.fracsize);
+	  p.fracsize += (p.exponent + to_shift) / BITS_PER_MP_LIMB;
+	}
+      else
+	{
+	  cy = __mpn_lshift (p.frac +
+			     (p.exponent + to_shift) / BITS_PER_MP_LIMB,
+			     fp_input, p.fracsize,
+			     (p.exponent + to_shift) % BITS_PER_MP_LIMB);
+	  p.fracsize += (p.exponent + to_shift) / BITS_PER_MP_LIMB;
+	  if (cy)
+	    p.frac[p.fracsize++] = cy;
+	}
+      MPN_ZERO (p.frac, (p.exponent + to_shift) / BITS_PER_MP_LIMB);
+
+      assert (powers > &_fpioconst_pow10[0]);
+      do
+	{
+	  --powers;
+
+	  /* The number of the product of two binary numbers with n and m
+	     bits respectively has m+n or m+n-1 bits.	*/
+	  if (p.exponent >= scaleexpo + powers->p_expo - 1)
+	    {
+	      if (p.scalesize == 0)
+		{
+#if __HAVE_DISTINCT_FLOAT128
+		  if ((FLT128_MANT_DIG
+			    > _FPIO_CONST_OFFSET * BITS_PER_MP_LIMB)
+			   && info->is_binary128)
+		    {
+#define _FLT128_FPIO_CONST_SHIFT \
+  (((FLT128_MANT_DIG + BITS_PER_MP_LIMB - 1) / BITS_PER_MP_LIMB) \
+   - _FPIO_CONST_OFFSET)
+		      /* 64bit const offset is not enough for
+			 IEEE 854 quad long double (_Float128).  */
+		      p.tmpsize = powers->arraysize + _FLT128_FPIO_CONST_SHIFT;
+		      memcpy (p.tmp + _FLT128_FPIO_CONST_SHIFT,
+			      &__tens[powers->arrayoff],
+			      p.tmpsize * sizeof (mp_limb_t));
+		      MPN_ZERO (p.tmp, _FLT128_FPIO_CONST_SHIFT);
+		      /* Adjust p.exponent, as scaleexpo will be this much
+			 bigger too.  */
+		      p.exponent += _FLT128_FPIO_CONST_SHIFT * BITS_PER_MP_LIMB;
+		    }
+		  else
+#endif /* __HAVE_DISTINCT_FLOAT128 */
+#ifndef __NO_LONG_DOUBLE_MATH
+		  if (LDBL_MANT_DIG > _FPIO_CONST_OFFSET * BITS_PER_MP_LIMB
+		      && info->is_long_double)
+		    {
+#define _FPIO_CONST_SHIFT \
+  (((LDBL_MANT_DIG + BITS_PER_MP_LIMB - 1) / BITS_PER_MP_LIMB) \
+   - _FPIO_CONST_OFFSET)
+		      /* 64bit const offset is not enough for
+			 IEEE quad long double.  */
+		      p.tmpsize = powers->arraysize + _FPIO_CONST_SHIFT;
+		      memcpy (p.tmp + _FPIO_CONST_SHIFT,
+			      &__tens[powers->arrayoff],
+			      p.tmpsize * sizeof (mp_limb_t));
+		      MPN_ZERO (p.tmp, _FPIO_CONST_SHIFT);
+		      /* Adjust p.exponent, as scaleexpo will be this much
+			 bigger too.  */
+		      p.exponent += _FPIO_CONST_SHIFT * BITS_PER_MP_LIMB;
+		    }
+		  else
+#endif
+		    {
+		      p.tmpsize = powers->arraysize;
+		      memcpy (p.tmp, &__tens[powers->arrayoff],
+			      p.tmpsize * sizeof (mp_limb_t));
+		    }
+		}
+	      else
+		{
+		  cy = __mpn_mul (p.tmp, p.scale, p.scalesize,
+				  &__tens[powers->arrayoff
+					 + _FPIO_CONST_OFFSET],
+				  powers->arraysize - _FPIO_CONST_OFFSET);
+		  p.tmpsize = p.scalesize +
+		    powers->arraysize - _FPIO_CONST_OFFSET;
+		  if (cy == 0)
+		    --p.tmpsize;
+		}
+
+	      if (MPN_GE (p.frac, p.tmp))
+		{
+		  int cnt;
+		  MPN_ASSIGN (p.scale, p.tmp);
+		  count_leading_zeros (cnt, p.scale[p.scalesize - 1]);
+		  scaleexpo = (p.scalesize - 2) * BITS_PER_MP_LIMB - cnt - 1;
+		  exp10 |= 1 << explog;
+		}
+	    }
+	  --explog;
+	}
+      while (powers > &_fpioconst_pow10[0]);
+      p.exponent = exp10;
+
+      /* Optimize number representations.  We want to represent the numbers
+	 with the lowest number of bytes possible without losing any
+	 bytes. Also the highest bit in the scaling factor has to be set
+	 (this is a requirement of the MPN division routines).  */
+      if (p.scalesize > 0)
+	{
+	  /* Determine minimum number of zero bits at the end of
+	     both numbers.  */
+	  for (i = 0; p.scale[i] == 0 && p.frac[i] == 0; i++)
+	    ;
+
+	  /* Determine number of bits the scaling factor is misplaced.	*/
+	  count_leading_zeros (cnt_h, p.scale[p.scalesize - 1]);
+
+	  if (cnt_h == 0)
+	    {
+	      /* The highest bit of the scaling factor is already set.	So
+		 we only have to remove the trailing empty limbs.  */
+	      if (i > 0)
+		{
+		  MPN_COPY_INCR (p.scale, p.scale + i, p.scalesize - i);
+		  p.scalesize -= i;
+		  MPN_COPY_INCR (p.frac, p.frac + i, p.fracsize - i);
+		  p.fracsize -= i;
+		}
+	    }
+	  else
+	    {
+	      if (p.scale[i] != 0)
+		{
+		  count_trailing_zeros (cnt_l, p.scale[i]);
+		  if (p.frac[i] != 0)
+		    {
+		      int cnt_l2;
+		      count_trailing_zeros (cnt_l2, p.frac[i]);
+		      if (cnt_l2 < cnt_l)
+			cnt_l = cnt_l2;
+		    }
+		}
+	      else
+		count_trailing_zeros (cnt_l, p.frac[i]);
+
+	      /* Now shift the numbers to their optimal position.  */
+	      if (i == 0 && BITS_PER_MP_LIMB - cnt_h > cnt_l)
+		{
+		  /* We cannot save any memory.	 So just roll both numbers
+		     so that the scaling factor has its highest bit set.  */
+
+		  (void) __mpn_lshift (p.scale, p.scale, p.scalesize, cnt_h);
+		  cy = __mpn_lshift (p.frac, p.frac, p.fracsize, cnt_h);
+		  if (cy != 0)
+		    p.frac[p.fracsize++] = cy;
+		}
+	      else if (BITS_PER_MP_LIMB - cnt_h <= cnt_l)
+		{
+		  /* We can save memory by removing the trailing zero limbs
+		     and by packing the non-zero limbs which gain another
+		     free one. */
+
+		  (void) __mpn_rshift (p.scale, p.scale + i, p.scalesize - i,
+				       BITS_PER_MP_LIMB - cnt_h);
+		  p.scalesize -= i + 1;
+		  (void) __mpn_rshift (p.frac, p.frac + i, p.fracsize - i,
+				       BITS_PER_MP_LIMB - cnt_h);
+		  p.fracsize -= p.frac[p.fracsize - i - 1] == 0 ? i + 1 : i;
+		}
+	      else
+		{
+		  /* We can only save the memory of the limbs which are zero.
+		     The non-zero parts occupy the same number of limbs.  */
+
+		  (void) __mpn_rshift (p.scale, p.scale + (i - 1),
+				       p.scalesize - (i - 1),
+				       BITS_PER_MP_LIMB - cnt_h);
+		  p.scalesize -= i;
+		  (void) __mpn_rshift (p.frac, p.frac + (i - 1),
+				       p.fracsize - (i - 1),
+				       BITS_PER_MP_LIMB - cnt_h);
+		  p.fracsize -=
+		    p.frac[p.fracsize - (i - 1) - 1] == 0 ? i : i - 1;
+		}
+	    }
+	}
+    }
+  else if (p.exponent < 0)
+    {
+      /* |FP| < 1.0.  */
+      int exp10 = 0;
+      int explog;
+#if __HAVE_DISTINCT_FLOAT128
+      if (info->is_binary128)
+	explog = FLT128_MAX_10_EXP_LOG;
+      else
+	explog = LDBL_MAX_10_EXP_LOG;
+#else
+      explog = LDBL_MAX_10_EXP_LOG;
+#endif
+      const struct mp_power *powers = &_fpioconst_pow10[explog + 1];
+
+      /* Now shift the input value to its right place.	*/
+      cy = __mpn_lshift (p.frac, fp_input, p.fracsize, to_shift);
+      p.frac[p.fracsize++] = cy;
+      assert (cy == 1 || (p.frac[p.fracsize - 2] == 0 && p.frac[0] == 0));
+
+      p.expsign = 1;
+      p.exponent = -p.exponent;
+
+      assert (powers != &_fpioconst_pow10[0]);
+      do
+	{
+	  --powers;
+
+	  if (p.exponent >= powers->m_expo)
+	    {
+	      int i, incr, cnt_h, cnt_l;
+	      mp_limb_t topval[2];
+
+	      /* The __mpn_mul function expects the first argument to be
+		 bigger than the second.  */
+	      if (p.fracsize < powers->arraysize - _FPIO_CONST_OFFSET)
+		cy = __mpn_mul (p.tmp, &__tens[powers->arrayoff
+					    + _FPIO_CONST_OFFSET],
+				powers->arraysize - _FPIO_CONST_OFFSET,
+				p.frac, p.fracsize);
+	      else
+		cy = __mpn_mul (p.tmp, p.frac, p.fracsize,
+				&__tens[powers->arrayoff + _FPIO_CONST_OFFSET],
+				powers->arraysize - _FPIO_CONST_OFFSET);
+	      p.tmpsize = p.fracsize + powers->arraysize - _FPIO_CONST_OFFSET;
+	      if (cy == 0)
+		--p.tmpsize;
+
+	      count_leading_zeros (cnt_h, p.tmp[p.tmpsize - 1]);
+	      incr = (p.tmpsize - p.fracsize) * BITS_PER_MP_LIMB
+		     + BITS_PER_MP_LIMB - 1 - cnt_h;
+
+	      assert (incr <= powers->p_expo);
+
+	      /* If we increased the p.exponent by exactly 3 we have to test
+		 for overflow.	This is done by comparing with 10 shifted
+		 to the right position.	 */
+	      if (incr == p.exponent + 3)
+		{
+		  if (cnt_h <= BITS_PER_MP_LIMB - 4)
+		    {
+		      topval[0] = 0;
+		      topval[1]
+			= ((mp_limb_t) 10) << (BITS_PER_MP_LIMB - 4 - cnt_h);
+		    }
+		  else
+		    {
+		      topval[0] = ((mp_limb_t) 10) << (BITS_PER_MP_LIMB - 4);
+		      topval[1] = 0;
+		      (void) __mpn_lshift (topval, topval, 2,
+					   BITS_PER_MP_LIMB - cnt_h);
+		    }
+		}
+
+	      /* We have to be careful when multiplying the last factor.
+		 If the result is greater than 1.0 be have to test it
+		 against 10.0.  If it is greater or equal to 10.0 the
+		 multiplication was not valid.  This is because we cannot
+		 determine the number of bits in the result in advance.  */
+	      if (incr < p.exponent + 3
+		  || (incr == p.exponent + 3 &&
+		      (p.tmp[p.tmpsize - 1] < topval[1]
+		       || (p.tmp[p.tmpsize - 1] == topval[1]
+			   && p.tmp[p.tmpsize - 2] < topval[0]))))
+		{
+		  /* The factor is right.  Adapt binary and decimal
+		     exponents.	 */
+		  p.exponent -= incr;
+		  exp10 |= 1 << explog;
+
+		  /* If this factor yields a number greater or equal to
+		     1.0, we must not shift the non-fractional digits down. */
+		  if (p.exponent < 0)
+		    cnt_h += -p.exponent;
+
+		  /* Now we optimize the number representation.	 */
+		  for (i = 0; p.tmp[i] == 0; ++i);
+		  if (cnt_h == BITS_PER_MP_LIMB - 1)
+		    {
+		      MPN_COPY (p.frac, p.tmp + i, p.tmpsize - i);
+		      p.fracsize = p.tmpsize - i;
+		    }
+		  else
+		    {
+		      count_trailing_zeros (cnt_l, p.tmp[i]);
+
+		      /* Now shift the numbers to their optimal position.  */
+		      if (i == 0 && BITS_PER_MP_LIMB - 1 - cnt_h > cnt_l)
+			{
+			  /* We cannot save any memory.	 Just roll the
+			     number so that the leading digit is in a
+			     separate limb.  */
+
+			  cy = __mpn_lshift (p.frac, p.tmp, p.tmpsize,
+			    cnt_h + 1);
+			  p.fracsize = p.tmpsize + 1;
+			  p.frac[p.fracsize - 1] = cy;
+			}
+		      else if (BITS_PER_MP_LIMB - 1 - cnt_h <= cnt_l)
+			{
+			  (void) __mpn_rshift (p.frac, p.tmp + i, p.tmpsize - i,
+					       BITS_PER_MP_LIMB - 1 - cnt_h);
+			  p.fracsize = p.tmpsize - i;
+			}
+		      else
+			{
+			  /* We can only save the memory of the limbs which
+			     are zero.	The non-zero parts occupy the same
+			     number of limbs.  */
+
+			  (void) __mpn_rshift (p.frac, p.tmp + (i - 1),
+					       p.tmpsize - (i - 1),
+					       BITS_PER_MP_LIMB - 1 - cnt_h);
+			  p.fracsize = p.tmpsize - (i - 1);
+			}
+		    }
+		}
+	    }
+	  --explog;
+	}
+      while (powers != &_fpioconst_pow10[1] && p.exponent > 0);
+      /* All factors but 10^-1 are tested now.	*/
+      if (p.exponent > 0)
+	{
+	  int cnt_l;
+
+	  cy = __mpn_mul_1 (p.tmp, p.frac, p.fracsize, 10);
+	  p.tmpsize = p.fracsize;
+	  assert (cy == 0 || p.tmp[p.tmpsize - 1] < 20);
+
+	  count_trailing_zeros (cnt_l, p.tmp[0]);
+	  if (cnt_l < MIN (4, p.exponent))
+	    {
+	      cy = __mpn_lshift (p.frac, p.tmp, p.tmpsize,
+				 BITS_PER_MP_LIMB - MIN (4, p.exponent));
+	      if (cy != 0)
+		p.frac[p.tmpsize++] = cy;
+	    }
+	  else
+	    (void) __mpn_rshift (p.frac, p.tmp, p.tmpsize, MIN (4, p.exponent));
+	  p.fracsize = p.tmpsize;
+	  exp10 |= 1;
+	  assert (p.frac[p.fracsize - 1] < 10);
+	}
+      p.exponent = exp10;
+    }
+  else
+    {
+      /* This is a special case.  We don't need a factor because the
+	 numbers are in the range of 1.0 <= |fp| < 8.0.  We simply
+	 shift it to the right place and divide it by 1.0 to get the
+	 leading digit.	 (Of course this division is not really made.)	*/
+      assert (0 <= p.exponent && p.exponent < 3 &&
+	      p.exponent + to_shift < BITS_PER_MP_LIMB);
+
+      /* Now shift the input value to its right place.	*/
+      cy = __mpn_lshift (p.frac, fp_input, p.fracsize, (p.exponent + to_shift));
+      p.frac[p.fracsize++] = cy;
+      p.exponent = 0;
+    }
+
+  {
+    int width = info->width;
+    wchar_t *wstartp, *wcp;
+    size_t chars_needed;
+    int expscale;
+    int intdig_max, intdig_no = 0;
+    int fracdig_min;
+    int fracdig_max;
+    int dig_max;
+    int significant;
+    int ngroups = 0;
+    char spec = _tolower (info->spec);
+
+    if (spec == 'e')
+      {
+	p.type = info->spec;
+	intdig_max = 1;
+	fracdig_min = fracdig_max = info->prec < 0 ? 6 : info->prec;
+	chars_needed = 1 + 1 + (size_t) fracdig_max + 1 + 1 + 4;
+	/*	       d   .	 ddd	     e	 +-  ddd  */
+	dig_max = INT_MAX;		/* Unlimited.  */
+	significant = 1;		/* Does not matter here.  */
+      }
+    else if (spec == 'f')
+      {
+	p.type = 'f';
+	fracdig_min = fracdig_max = info->prec < 0 ? 6 : info->prec;
+	dig_max = INT_MAX;		/* Unlimited.  */
+	significant = 1;		/* Does not matter here.  */
+	if (p.expsign == 0)
+	  {
+	    intdig_max = p.exponent + 1;
+	    /* This can be really big!	*/  /* XXX Maybe malloc if too big? */
+	    chars_needed = (size_t) p.exponent + 1 + 1 + (size_t) fracdig_max;
+	  }
+	else
+	  {
+	    intdig_max = 1;
+	    chars_needed = 1 + 1 + (size_t) fracdig_max;
+	  }
+      }
+    else
+      {
+	dig_max = info->prec < 0 ? 6 : (info->prec == 0 ? 1 : info->prec);
+	if ((p.expsign == 0 && p.exponent >= dig_max)
+	    || (p.expsign != 0 && p.exponent > 4))
+	  {
+	    if ('g' - 'G' == 'e' - 'E')
+	      p.type = 'E' + (info->spec - 'G');
+	    else
+	      p.type = isupper (info->spec) ? 'E' : 'e';
+	    fracdig_max = dig_max - 1;
+	    intdig_max = 1;
+	    chars_needed = 1 + 1 + (size_t) fracdig_max + 1 + 1 + 4;
+	  }
+	else
+	  {
+	    p.type = 'f';
+	    intdig_max = p.expsign == 0 ? p.exponent + 1 : 0;
+	    fracdig_max = dig_max - intdig_max;
+	    /* We need space for the significant digits and perhaps
+	       for leading zeros when < 1.0.  The number of leading
+	       zeros can be as many as would be required for
+	       exponential notation with a negative two-digit
+	       p.exponent, which is 4.  */
+	    chars_needed = (size_t) dig_max + 1 + 4;
+	  }
+	fracdig_min = info->alt ? fracdig_max : 0;
+	significant = 0;		/* We count significant digits.	 */
+      }
+
+    if (grouping)
+      {
+	/* Guess the number of groups we will make, and thus how
+	   many spaces we need for separator characters.  */
+	ngroups = __guess_grouping (intdig_max, grouping);
+	/* Allocate one more character in case rounding increases the
+	   number of groups.  */
+	chars_needed += ngroups + 1;
+      }
+
+    /* Allocate buffer for output.  We need two more because while rounding
+       it is possible that we need two more characters in front of all the
+       other output.  If the amount of memory we have to allocate is too
+       large use `malloc' instead of `alloca'.  */
+    if (__builtin_expect (chars_needed >= (size_t) -1 / sizeof (wchar_t) - 2
+			  || chars_needed < fracdig_max, 0))
+      {
+	/* Some overflow occurred.  */
+	__set_errno (ERANGE);
+	return -1;
+      }
+    size_t wbuffer_to_alloc = (2 + chars_needed) * sizeof (wchar_t);
+    buffer_malloced = ! __libc_use_alloca (wbuffer_to_alloc);
+    if (__builtin_expect (buffer_malloced, 0))
+      {
+	wbuffer = (wchar_t *) malloc (wbuffer_to_alloc);
+	if (wbuffer == NULL)
+	  /* Signal an error to the caller.  */
+	  return -1;
+      }
+    else
+      wbuffer = (wchar_t *) alloca (wbuffer_to_alloc);
+    wcp = wstartp = wbuffer + 2;	/* Let room for rounding.  */
+
+    /* Do the real work: put digits in allocated buffer.  */
+    if (p.expsign == 0 || p.type != 'f')
+      {
+	assert (p.expsign == 0 || intdig_max == 1);
+	while (intdig_no < intdig_max)
+	  {
+	    ++intdig_no;
+	    *wcp++ = hack_digit (&p);
+	  }
+	significant = 1;
+	if (info->alt
+	    || fracdig_min > 0
+	    || (fracdig_max > 0 && (p.fracsize > 1 || p.frac[0] != 0)))
+	  *wcp++ = decimalwc;
+      }
+    else
+      {
+	/* |fp| < 1.0 and the selected p.type is 'f', so put "0."
+	   in the buffer.  */
+	*wcp++ = L'0';
+	--p.exponent;
+	*wcp++ = decimalwc;
+      }
+
+    /* Generate the needed number of fractional digits.	 */
+    int fracdig_no = 0;
+    int added_zeros = 0;
+    while (fracdig_no < fracdig_min + added_zeros
+	   || (fracdig_no < fracdig_max && (p.fracsize > 1 || p.frac[0] != 0)))
+      {
+	++fracdig_no;
+	*wcp = hack_digit (&p);
+	if (*wcp++ != L'0')
+	  significant = 1;
+	else if (significant == 0)
+	  {
+	    ++fracdig_max;
+	    if (fracdig_min > 0)
+	      ++added_zeros;
+	  }
+      }
+
+    /* Do rounding.  */
+    wchar_t last_digit = wcp[-1] != decimalwc ? wcp[-1] : wcp[-2];
+    wchar_t next_digit = hack_digit (&p);
+    bool more_bits;
+    if (next_digit != L'0' && next_digit != L'5')
+      more_bits = true;
+    else if (p.fracsize == 1 && p.frac[0] == 0)
+      /* Rest of the number is zero.  */
+      more_bits = false;
+    else if (p.scalesize == 0)
+      {
+	/* Here we have to see whether all limbs are zero since no
+	   normalization happened.  */
+	size_t lcnt = p.fracsize;
+	while (lcnt >= 1 && p.frac[lcnt - 1] == 0)
+	  --lcnt;
+	more_bits = lcnt > 0;
+      }
+    else
+      more_bits = true;
+    int rounding_mode = get_rounding_mode ();
+    if (round_away (is_neg, (last_digit - L'0') & 1, next_digit >= L'5',
+		    more_bits, rounding_mode))
+      {
+	wchar_t *wtp = wcp;
+
+	if (fracdig_no > 0)
+	  {
+	    /* Process fractional digits.  Terminate if not rounded or
+	       radix character is reached.  */
+	    int removed = 0;
+	    while (*--wtp != decimalwc && *wtp == L'9')
+	      {
+		*wtp = L'0';
+		++removed;
+	      }
+	    if (removed == fracdig_min && added_zeros > 0)
+	      --added_zeros;
+	    if (*wtp != decimalwc)
+	      /* Round up.  */
+	      (*wtp)++;
+	    else if (__builtin_expect (spec == 'g' && p.type == 'f' && info->alt
+				       && wtp == wstartp + 1
+				       && wstartp[0] == L'0',
+				       0))
+	      /* This is a special case: the rounded number is 1.0,
+		 the format is 'g' or 'G', and the alternative format
+		 is selected.  This means the result must be "1.".  */
+	      --added_zeros;
+	  }
+
+	if (fracdig_no == 0 || *wtp == decimalwc)
+	  {
+	    /* Round the integer digits.  */
+	    if (*(wtp - 1) == decimalwc)
+	      --wtp;
+
+	    while (--wtp >= wstartp && *wtp == L'9')
+	      *wtp = L'0';
+
+	    if (wtp >= wstartp)
+	      /* Round up.  */
+	      (*wtp)++;
+	    else
+	      /* It is more critical.  All digits were 9's.  */
+	      {
+		if (p.type != 'f')
+		  {
+		    *wstartp = '1';
+		    p.exponent += p.expsign == 0 ? 1 : -1;
+
+		    /* The above p.exponent adjustment could lead to 1.0e-00,
+		       e.g. for 0.999999999.  Make sure p.exponent 0 always
+		       uses + sign.  */
+		    if (p.exponent == 0)
+		      p.expsign = 0;
+		  }
+		else if (intdig_no == dig_max)
+		  {
+		    /* This is the case where for p.type %g the number fits
+		       really in the range for %f output but after rounding
+		       the number of digits is too big.	 */
+		    *--wstartp = decimalwc;
+		    *--wstartp = L'1';
+
+		    if (info->alt || fracdig_no > 0)
+		      {
+			/* Overwrite the old radix character.  */
+			wstartp[intdig_no + 2] = L'0';
+			++fracdig_no;
+		      }
+
+		    fracdig_no += intdig_no;
+		    intdig_no = 1;
+		    fracdig_max = intdig_max - intdig_no;
+		    ++p.exponent;
+		    /* Now we must print the p.exponent.	*/
+		    p.type = isupper (info->spec) ? 'E' : 'e';
+		  }
+		else
+		  {
+		    /* We can simply add another another digit before the
+		       radix.  */
+		    *--wstartp = L'1';
+		    ++intdig_no;
+		  }
+
+		/* While rounding the number of digits can change.
+		   If the number now exceeds the limits remove some
+		   fractional digits.  */
+		if (intdig_no + fracdig_no > dig_max)
+		  {
+		    wcp -= intdig_no + fracdig_no - dig_max;
+		    fracdig_no -= intdig_no + fracdig_no - dig_max;
+		  }
+	      }
+	  }
+      }
+
+    /* Now remove unnecessary '0' at the end of the string.  */
+    while (fracdig_no > fracdig_min + added_zeros && *(wcp - 1) == L'0')
+      {
+	--wcp;
+	--fracdig_no;
+      }
+    /* If we eliminate all fractional digits we perhaps also can remove
+       the radix character.  */
+    if (fracdig_no == 0 && !info->alt && *(wcp - 1) == decimalwc)
+      --wcp;
+
+    if (grouping)
+      {
+	/* Rounding might have changed the number of groups.  We allocated
+	   enough memory but we need here the correct number of groups.  */
+	if (intdig_no != intdig_max)
+	  ngroups = __guess_grouping (intdig_no, grouping);
+
+	/* Add in separator characters, overwriting the same buffer.  */
+	wcp = group_number (wstartp, wcp, intdig_no, grouping, thousands_sepwc,
+			    ngroups);
+      }
+
+    /* Write the p.exponent if it is needed.  */
+    if (p.type != 'f')
+      {
+	if (__glibc_unlikely (p.expsign != 0 && p.exponent == 4 && spec == 'g'))
+	  {
+	    /* This is another special case.  The p.exponent of the number is
+	       really smaller than -4, which requires the 'e'/'E' format.
+	       But after rounding the number has an p.exponent of -4.  */
+	    assert (wcp >= wstartp + 1);
+	    assert (wstartp[0] == L'1');
+	    __wmemcpy (wstartp, L"0.0001", 6);
+	    wstartp[1] = decimalwc;
+	    if (wcp >= wstartp + 2)
+	      {
+		__wmemset (wstartp + 6, L'0', wcp - (wstartp + 2));
+		wcp += 4;
+	      }
+	    else
+	      wcp += 5;
+	  }
+	else
+	  {
+	    *wcp++ = (wchar_t) p.type;
+	    *wcp++ = p.expsign ? L'-' : L'+';
+
+	    /* Find the magnitude of the p.exponent.	*/
+	    expscale = 10;
+	    while (expscale <= p.exponent)
+	      expscale *= 10;
+
+	    if (p.exponent < 10)
+	      /* Exponent always has at least two digits.  */
+	      *wcp++ = L'0';
+	    else
+	      do
+		{
+		  expscale /= 10;
+		  *wcp++ = L'0' + (p.exponent / expscale);
+		  p.exponent %= expscale;
+		}
+	      while (expscale > 10);
+	    *wcp++ = L'0' + p.exponent;
+	  }
+      }
+
+    /* Compute number of characters which must be filled with the padding
+       character.  */
+    if (is_neg || info->showsign || info->space)
+      --width;
+    width -= wcp - wstartp;
+
+    if (!info->left && info->pad != '0' && width > 0)
+      PADN (info->pad, width);
+
+    if (is_neg)
+      outchar ('-');
+    else if (info->showsign)
+      outchar ('+');
+    else if (info->space)
+      outchar (' ');
+
+    if (!info->left && info->pad == '0' && width > 0)
+      PADN ('0', width);
+
+    {
+      char *buffer = NULL;
+      char *buffer_end = NULL;
+      char *cp = NULL;
+      char *tmpptr;
+
+      if (! wide)
+	{
+	  /* Create the single byte string.  */
+	  size_t decimal_len;
+	  size_t thousands_sep_len;
+	  wchar_t *copywc;
+	  size_t factor;
+	  if (info->i18n)
+	    factor = _nl_lookup_word (loc, LC_CTYPE, _NL_CTYPE_MB_CUR_MAX);
+	  else
+	    factor = 1;
+
+	  decimal_len = strlen (decimal);
+
+	  if (thousands_sep == NULL)
+	    thousands_sep_len = 0;
+	  else
+	    thousands_sep_len = strlen (thousands_sep);
+
+	  size_t nbuffer = (2 + chars_needed * factor + decimal_len
+			    + ngroups * thousands_sep_len);
+	  if (__glibc_unlikely (buffer_malloced))
+	    {
+	      buffer = (char *) malloc (nbuffer);
+	      if (buffer == NULL)
+		{
+		  /* Signal an error to the caller.  */
+		  free (wbuffer);
+		  return -1;
+		}
+	    }
+	  else
+	    buffer = (char *) alloca (nbuffer);
+	  buffer_end = buffer + nbuffer;
+
+	  /* Now copy the wide character string.  Since the character
+	     (except for the decimal point and thousands separator) must
+	     be coming from the ASCII range we can esily convert the
+	     string without mapping tables.  */
+	  for (cp = buffer, copywc = wstartp; copywc < wcp; ++copywc)
+	    if (*copywc == decimalwc)
+	      cp = (char *) __mempcpy (cp, decimal, decimal_len);
+	    else if (*copywc == thousands_sepwc)
+	      cp = (char *) __mempcpy (cp, thousands_sep, thousands_sep_len);
+	    else
+	      *cp++ = (char) *copywc;
+	}
+
+      tmpptr = buffer;
+      if (__glibc_unlikely (info->i18n))
+	{
+#ifdef COMPILE_WPRINTF
+	  wstartp = _i18n_number_rewrite (wstartp, wcp,
+					  wbuffer + wbuffer_to_alloc);
+	  wcp = wbuffer + wbuffer_to_alloc;
+	  assert ((uintptr_t) wbuffer <= (uintptr_t) wstartp);
+	  assert ((uintptr_t) wstartp
+		  < (uintptr_t) wbuffer + wbuffer_to_alloc);
+#else
+	  tmpptr = _i18n_number_rewrite (tmpptr, cp, buffer_end);
+	  cp = buffer_end;
+	  assert ((uintptr_t) buffer <= (uintptr_t) tmpptr);
+	  assert ((uintptr_t) tmpptr < (uintptr_t) buffer_end);
+#endif
+	}
+
+      PRINT (tmpptr, wstartp, wide ? wcp - wstartp : cp - tmpptr);
+
+      /* Free the memory if necessary.  */
+      if (__glibc_unlikely (buffer_malloced))
+	{
+	  free (buffer);
+	  free (wbuffer);
+	}
+    }
+
+    if (info->left && width > 0)
+      PADN (info->pad, width);
+  }
+  return done;
+}
+libc_hidden_def (__printf_fp_l)
+
+int
+___printf_fp (FILE *fp, const struct printf_info *info,
+	      const void *const *args)
+{
+  return __printf_fp_l (fp, _NL_CURRENT_LOCALE, info, args);
+}
+ldbl_hidden_def (___printf_fp, __printf_fp)
+ldbl_strong_alias (___printf_fp, __printf_fp)
+
+
+/* Return the number of extra grouping characters that will be inserted
+   into a number with INTDIG_MAX integer digits.  */
+
+unsigned int
+__guess_grouping (unsigned int intdig_max, const char *grouping)
+{
+  unsigned int groups;
+
+  /* We treat all negative values like CHAR_MAX.  */
+
+  if (*grouping == CHAR_MAX || *grouping <= 0)
+    /* No grouping should be done.  */
+    return 0;
+
+  groups = 0;
+  while (intdig_max > (unsigned int) *grouping)
+    {
+      ++groups;
+      intdig_max -= *grouping++;
+
+      if (*grouping == CHAR_MAX
+#if CHAR_MIN < 0
+	  || *grouping < 0
+#endif
+	  )
+	/* No more grouping should be done.  */
+	break;
+      else if (*grouping == 0)
+	{
+	  /* Same grouping repeats.  */
+	  groups += (intdig_max - 1) / grouping[-1];
+	  break;
+	}
+    }
+
+  return groups;
+}
+
+/* Group the INTDIG_NO integer digits of the number in [BUF,BUFEND).
+   There is guaranteed enough space past BUFEND to extend it.
+   Return the new end of buffer.  */
+
+static wchar_t *
+internal_function
+group_number (wchar_t *buf, wchar_t *bufend, unsigned int intdig_no,
+	      const char *grouping, wchar_t thousands_sep, int ngroups)
+{
+  wchar_t *p;
+
+  if (ngroups == 0)
+    return bufend;
+
+  /* Move the fractional part down.  */
+  __wmemmove (buf + intdig_no + ngroups, buf + intdig_no,
+	      bufend - (buf + intdig_no));
+
+  p = buf + intdig_no + ngroups - 1;
+  do
+    {
+      unsigned int len = *grouping++;
+      do
+	*p-- = buf[--intdig_no];
+      while (--len > 0);
+      *p-- = thousands_sep;
+
+      if (*grouping == CHAR_MAX
+#if CHAR_MIN < 0
+	  || *grouping < 0
+#endif
+	  )
+	/* No more grouping should be done.  */
+	break;
+      else if (*grouping == 0)
+	/* Same grouping repeats.  */
+	--grouping;
+    } while (intdig_no > (unsigned int) *grouping);
+
+  /* Copy the remaining ungrouped digits.  */
+  do
+    *p-- = buf[--intdig_no];
+  while (p > buf);
+
+  return bufend + ngroups;
+}