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-rw-r--r--stdlib/mod_1.c197
1 files changed, 0 insertions, 197 deletions
diff --git a/stdlib/mod_1.c b/stdlib/mod_1.c
deleted file mode 100644
index 3273c9222d..0000000000
--- a/stdlib/mod_1.c
+++ /dev/null
@@ -1,197 +0,0 @@
-/* mpn_mod_1(dividend_ptr, dividend_size, divisor_limb) --
-   Divide (DIVIDEND_PTR,,DIVIDEND_SIZE) by DIVISOR_LIMB.
-   Return the single-limb remainder.
-   There are no constraints on the value of the divisor.
-
-Copyright (C) 1991, 1993, 1994, Free Software Foundation, Inc.
-
-This file is part of the GNU MP Library.
-
-The GNU MP 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 MP 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 MP Library; see the file COPYING.LIB.  If not, write to
-the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
-MA 02111-1307, USA. */
-
-#include <gmp.h>
-#include "gmp-impl.h"
-#include "longlong.h"
-
-#ifndef UMUL_TIME
-#define UMUL_TIME 1
-#endif
-
-#ifndef UDIV_TIME
-#define UDIV_TIME UMUL_TIME
-#endif
-
-/* FIXME: We should be using invert_limb (or invert_normalized_limb)
-   here (not udiv_qrnnd).  */
-
-mp_limb_t
-#if __STDC__
-mpn_mod_1 (mp_srcptr dividend_ptr, mp_size_t dividend_size,
-	   mp_limb_t divisor_limb)
-#else
-mpn_mod_1 (dividend_ptr, dividend_size, divisor_limb)
-     mp_srcptr dividend_ptr;
-     mp_size_t dividend_size;
-     mp_limb_t divisor_limb;
-#endif
-{
-  mp_size_t i;
-  mp_limb_t n1, n0, r;
-  int dummy;
-
-  /* Botch: Should this be handled at all?  Rely on callers?  */
-  if (dividend_size == 0)
-    return 0;
-
-  /* If multiplication is much faster than division, and the
-     dividend is large, pre-invert the divisor, and use
-     only multiplications in the inner loop.  */
-
-  /* This test should be read:
-       Does it ever help to use udiv_qrnnd_preinv?
-	 && Does what we save compensate for the inversion overhead?  */
-  if (UDIV_TIME > (2 * UMUL_TIME + 6)
-      && (UDIV_TIME - (2 * UMUL_TIME + 6)) * dividend_size > UDIV_TIME)
-    {
-      int normalization_steps;
-
-      count_leading_zeros (normalization_steps, divisor_limb);
-      if (normalization_steps != 0)
-	{
-	  mp_limb_t divisor_limb_inverted;
-
-	  divisor_limb <<= normalization_steps;
-
-	  /* Compute (2**2N - 2**N * DIVISOR_LIMB) / DIVISOR_LIMB.  The
-	     result is a (N+1)-bit approximation to 1/DIVISOR_LIMB, with the
-	     most significant bit (with weight 2**N) implicit.  */
-
-	  /* Special case for DIVISOR_LIMB == 100...000.  */
-	  if (divisor_limb << 1 == 0)
-	    divisor_limb_inverted = ~(mp_limb_t) 0;
-	  else
-	    udiv_qrnnd (divisor_limb_inverted, dummy,
-			-divisor_limb, 0, divisor_limb);
-
-	  n1 = dividend_ptr[dividend_size - 1];
-	  r = n1 >> (BITS_PER_MP_LIMB - normalization_steps);
-
-	  /* Possible optimization:
-	     if (r == 0
-	     && divisor_limb > ((n1 << normalization_steps)
-			     | (dividend_ptr[dividend_size - 2] >> ...)))
-	     ...one division less... */
-
-	  for (i = dividend_size - 2; i >= 0; i--)
-	    {
-	      n0 = dividend_ptr[i];
-	      udiv_qrnnd_preinv (dummy, r, r,
-				 ((n1 << normalization_steps)
-				  | (n0 >> (BITS_PER_MP_LIMB - normalization_steps))),
-				 divisor_limb, divisor_limb_inverted);
-	      n1 = n0;
-	    }
-	  udiv_qrnnd_preinv (dummy, r, r,
-			     n1 << normalization_steps,
-			     divisor_limb, divisor_limb_inverted);
-	  return r >> normalization_steps;
-	}
-      else
-	{
-	  mp_limb_t divisor_limb_inverted;
-
-	  /* Compute (2**2N - 2**N * DIVISOR_LIMB) / DIVISOR_LIMB.  The
-	     result is a (N+1)-bit approximation to 1/DIVISOR_LIMB, with the
-	     most significant bit (with weight 2**N) implicit.  */
-
-	  /* Special case for DIVISOR_LIMB == 100...000.  */
-	  if (divisor_limb << 1 == 0)
-	    divisor_limb_inverted = ~(mp_limb_t) 0;
-	  else
-	    udiv_qrnnd (divisor_limb_inverted, dummy,
-			-divisor_limb, 0, divisor_limb);
-
-	  i = dividend_size - 1;
-	  r = dividend_ptr[i];
-
-	  if (r >= divisor_limb)
-	    r = 0;
-	  else
-	    i--;
-
-	  for (; i >= 0; i--)
-	    {
-	      n0 = dividend_ptr[i];
-	      udiv_qrnnd_preinv (dummy, r, r,
-				 n0, divisor_limb, divisor_limb_inverted);
-	    }
-	  return r;
-	}
-    }
-  else
-    {
-      if (UDIV_NEEDS_NORMALIZATION)
-	{
-	  int normalization_steps;
-
-	  count_leading_zeros (normalization_steps, divisor_limb);
-	  if (normalization_steps != 0)
-	    {
-	      divisor_limb <<= normalization_steps;
-
-	      n1 = dividend_ptr[dividend_size - 1];
-	      r = n1 >> (BITS_PER_MP_LIMB - normalization_steps);
-
-	      /* Possible optimization:
-		 if (r == 0
-		 && divisor_limb > ((n1 << normalization_steps)
-				 | (dividend_ptr[dividend_size - 2] >> ...)))
-		 ...one division less... */
-
-	      for (i = dividend_size - 2; i >= 0; i--)
-		{
-		  n0 = dividend_ptr[i];
-		  udiv_qrnnd (dummy, r, r,
-			      ((n1 << normalization_steps)
-			       | (n0 >> (BITS_PER_MP_LIMB - normalization_steps))),
-			      divisor_limb);
-		  n1 = n0;
-		}
-	      udiv_qrnnd (dummy, r, r,
-			  n1 << normalization_steps,
-			  divisor_limb);
-	      return r >> normalization_steps;
-	    }
-	}
-      /* No normalization needed, either because udiv_qrnnd doesn't require
-	 it, or because DIVISOR_LIMB is already normalized.  */
-
-      i = dividend_size - 1;
-      r = dividend_ptr[i];
-
-      if (r >= divisor_limb)
-	r = 0;
-      else
-	i--;
-
-      for (; i >= 0; i--)
-	{
-	  n0 = dividend_ptr[i];
-	  udiv_qrnnd (dummy, r, r, n0, divisor_limb);
-	}
-      return r;
-    }
-}