initial import

1 files changed, 213 insertions, 0 deletions

diff --git a/sysdeps/generic/get_str.c b/sysdeps/generic/get_str.c
new file mode 100644
index 0000000000..182815ee18
--- /dev/null
+++ b/sysdeps/generic/get_str.c
@@ -0,0 +1,213 @@
+/* __mpn_get_str -- Convert a MSIZE long limb vector pointed to by MPTR
+   to a printable string in STR in base BASE.
+
+Copyright (C) 1991, 1992, 1993 Free Software Foundation, Inc.
+
+
+This file is part of the GNU C Library.  Its master source is NOT part of
+the C library, however.  This file is in fact copied from the GNU MP
+Library and its source lives there.
+
+The GNU C Library 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.
+
+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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include "gmp.h"
+#include "gmp-impl.h"
+
+/* Convert the limb vector pointed to by MPTR and MSIZE long to a
+   char array, using base BASE for the result array.  Store the
+   result in the character array STR.  STR must point to an array with
+   space for the largest possible number represented by a MSIZE long
+   limb vector + 1 extra character.
+
+   The result is NOT in Ascii, to convert it to printable format, add
+   '0' or 'A' depending on the base and range.
+
+   Return the number of digits in the result string.
+   This may include some leading zeros.
+
+   The limb vector pointed to by MPTR is clobbered.  */
+
+size_t
+__mpn_get_str (str, base, mptr, msize)
+     unsigned char *str;
+     int base;
+     mp_ptr mptr;
+     mp_size_t msize;
+{
+  mp_limb big_base;
+#if UDIV_NEEDS_NORMALIZATION || UDIV_TIME > 2 * UMUL_TIME
+  int normalization_steps;
+#endif
+#if UDIV_TIME > 2 * UMUL_TIME
+  mp_limb big_base_inverted;
+#endif
+  unsigned int dig_per_u;
+  mp_size_t out_len;
+  register unsigned char *s;
+
+  big_base = __mp_bases[base].big_base;
+
+  s = str;
+
+  /* Special case zero, as the code below doesn't handle it.  */
+  if (msize == 0)
+    {
+      s[0] = 0;
+      return 1;
+    }
+
+  if ((base & (base - 1)) == 0)
+    {
+      /* The base is a power of 2.  Make conversion from most
+	 significant side.  */
+      mp_limb n1, n0;
+      register int bits_per_digit = big_base;
+      register int x;
+      register int bit_pos;
+      register int i;
+
+      n1 = mptr[msize - 1];
+      count_leading_zeros (x, n1);
+
+	/* BIT_POS should be R when input ends in least sign. nibble,
+	   R + bits_per_digit * n when input ends in n:th least significant
+	   nibble. */
+
+      {
+	int bits;
+
+	bits = BITS_PER_MP_LIMB * msize - x;
+	x = bits % bits_per_digit;
+	if (x != 0)
+	  bits += bits_per_digit - x;
+	bit_pos = bits - (msize - 1) * BITS_PER_MP_LIMB;
+      }
+
+      /* Fast loop for bit output.  */
+      i = msize - 1;
+      for (;;)
+	{
+	  bit_pos -= bits_per_digit;
+	  while (bit_pos >= 0)
+	    {
+	      *s++ = (n1 >> bit_pos) & ((1 << bits_per_digit) - 1);
+	      bit_pos -= bits_per_digit;
+	    }
+	  i--;
+	  if (i < 0)
+	    break;
+	  n0 = (n1 << -bit_pos) & ((1 << bits_per_digit) - 1);
+	  n1 = mptr[i];
+	  bit_pos += BITS_PER_MP_LIMB;
+	  *s++ = n0 | (n1 >> bit_pos);
+	}
+
+      *s = 0;
+
+      return s - str;
+    }
+  else
+    {
+      /* General case.  The base is not a power of 2.  Make conversion
+	 from least significant end.  */
+
+      /* If udiv_qrnnd only handles divisors with the most significant bit
+	 set, prepare BIG_BASE for being a divisor by shifting it to the
+	 left exactly enough to set the most significant bit.  */
+#if UDIV_NEEDS_NORMALIZATION || UDIV_TIME > 2 * UMUL_TIME
+      count_leading_zeros (normalization_steps, big_base);
+      big_base <<= normalization_steps;
+#if UDIV_TIME > 2 * UMUL_TIME
+      /* Get the fixed-point approximation to 1/(BIG_BASE << NORMALIZATION_STEPS).  */
+      big_base_inverted = __mp_bases[base].big_base_inverted;
+#endif
+#endif
+
+      dig_per_u = __mp_bases[base].chars_per_limb;
+      out_len = ((size_t) msize * BITS_PER_MP_LIMB
+		 * __mp_bases[base].chars_per_bit_exactly) + 1;
+      s += out_len;
+
+      while (msize != 0)
+	{
+	  int i;
+	  mp_limb n0, n1;
+
+#if UDIV_NEEDS_NORMALIZATION || UDIV_TIME > 2 * UMUL_TIME
+	  /* If we shifted BIG_BASE above, shift the dividend too, to get
+	     the right quotient.  We need to do this every loop,
+	     since the intermediate quotients are OK, but the quotient from
+	     one turn in the loop is going to be the dividend in the
+	     next turn, and the dividend needs to be up-shifted.  */
+	  if (normalization_steps != 0)
+	    {
+	      n0 = __mpn_lshift (mptr, mptr, msize, normalization_steps);
+
+	      /* If the shifting gave a carry out limb, store it and
+		 increase the length.  */
+	      if (n0 != 0)
+		{
+		  mptr[msize] = n0;
+		  msize++;
+		}
+	    }
+#endif
+
+	  /* Divide the number at TP with BIG_BASE to get a quotient and a
+	     remainder.  The remainder is our new digit in base BIG_BASE.  */
+	  i = msize - 1;
+	  n1 = mptr[i];
+
+	  if (n1 >= big_base)
+	    n1 = 0;
+	  else
+	    {
+	      msize--;
+	      i--;
+	    }
+
+	  for (; i >= 0; i--)
+	    {
+	      n0 = mptr[i];
+#if UDIV_TIME > 2 * UMUL_TIME
+	      udiv_qrnnd_preinv (mptr[i], n1, n1, n0, big_base, big_base_inverted);
+#else
+	      udiv_qrnnd (mptr[i], n1, n1, n0, big_base);
+#endif
+	    }
+
+#if UDIV_NEEDS_NORMALIZATION || UDIV_TIME > 2 * UMUL_TIME
+	  /* If we shifted above (at previous UDIV_NEEDS_NORMALIZATION tests)
+	     the remainder will be up-shifted here.  Compensate.  */
+	  n1 >>= normalization_steps;
+#endif
+
+	  /* Convert N1 from BIG_BASE to a string of digits in BASE
+	     using single precision operations.  */
+	  for (i = dig_per_u - 1; i >= 0; i--)
+	    {
+	      *--s = n1 % base;
+	      n1 /= base;
+	      if (n1 == 0 && msize == 0)
+		break;
+	    }
+	}
+
+      while (s != str)
+	*--s = 0;
+      return out_len;
+    }
+}