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authorUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
committerUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
commita334319f6530564d22e775935d9c91663623a1b4 (patch)
treeb5877475619e4c938e98757d518bb1e9cbead751 /stdlib/mod_1.c
parent0ecb606cb6cf65de1d9fc8a919bceb4be476c602 (diff)
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(CFLAGS-tst-align.c): Add -mpreferred-stack-boundary=4.
Diffstat (limited to 'stdlib/mod_1.c')
-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 3273c92..0000000
--- 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;
- }
-}