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116 lines
2.2 KiB
C
116 lines
2.2 KiB
C
/* Libgcc Target specific implementation - Emulating div and mod.
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Copyright (C) 2012-2015 Free Software Foundation, Inc.
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Contributed by KPIT Cummins Infosystems Limited.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3, or (at your option)
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any later version.
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GCC is distributed in the hope that it will be useful, but WITHOUT
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
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License for more details.
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Under Section 7 of GPL version 3, you are granted additional
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permissions described in the GCC Runtime Library Exception, version
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3.1, as published by the Free Software Foundation.
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You should have received a copy of the GNU General Public License and
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a copy of the GCC Runtime Library Exception along with this program;
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see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
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<http://www.gnu.org/licenses/>. */
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/* Emulate the division and modulus operation. */
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unsigned short
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udivmodhi4 (unsigned short num, unsigned short den, short modwanted)
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{
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unsigned short bit = 1;
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unsigned short res = 0;
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while (den < num && bit && !(den & (1 << 15)))
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{
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den <<= 1;
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bit <<= 1;
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}
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while (bit)
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{
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if (num >= den)
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{
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num -= den;
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res |= bit;
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}
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bit >>= 1;
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den >>= 1;
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}
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if (modwanted)
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return num;
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return res;
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}
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short
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__divhi3 (short a, short b)
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{
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short neg = 0;
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short res;
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if (a < 0)
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{
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a = -a;
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neg = !neg;
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}
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if (b < 0)
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{
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b = -b;
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neg = !neg;
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}
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res = udivmodhi4 (a, b, 0);
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if (neg)
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res = -res;
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return res;
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}
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short
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__modhi3 (short a, short b)
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{
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short neg = 0;
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short res;
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if (a < 0)
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{
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a = -a;
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neg = 1;
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}
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if (b < 0)
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b = -b;
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res = udivmodhi4 (a, b, 1);
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if (neg)
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res = -res;
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return res;
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}
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short
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__udivhi3 (short a, short b)
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{
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return udivmodhi4 (a, b, 0);
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}
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short
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__umodhi3 (short a, short b)
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{
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return udivmodhi4 (a, b, 1);
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}
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