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71 lines
2.2 KiB
C
71 lines
2.2 KiB
C
/* Copyright (C) 2004-2019 Free Software Foundation, Inc.
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Contributor: Joern Rennecke <joern.rennecke@embecosm.com>
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on behalf of Synopsys Inc.
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This file 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 the
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Free Software Foundation; either version 3, or (at your option) any
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later version.
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In addition to the permissions in the GNU General Public License, the
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Free Software Foundation gives you unlimited permission to link the
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compiled version of this file into combinations with other programs,
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and to distribute those combinations without any restriction coming
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from the use of this file. (The General Public License restrictions
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do apply in other respects; for example, they cover modification of
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the file, and distribution when not linked into a combine
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executable.)
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This file is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; see the file COPYING3. If not see
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<http://www.gnu.org/licenses/>. */
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/* Calculate division table for ARC700 integer division
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Contributed by Joern Rennecke
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joern.rennecke@arc.com */
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#include <stdio.h>
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#include <math.h>
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int
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main ()
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{
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int i, j;
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unsigned x;
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double q, r, err, max_err = -1;
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puts("/* This table has been generated by divtab-arc700.c. */");
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puts("\
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/* 1/512 .. 1/256, normalized. There is a leading 1 in bit 31.\n\
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For powers of two, we list unnormalized numbers instead. The values\n\
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for powers of 2 are loaded, but not used. The value for 1 is actually\n\
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the first instruction after .Lmuldiv. */\n\
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.balign 4");
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puts (".Ldivtab:\n");
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for (i = 256; i >= 2; --i)
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{
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j = i < 0 ? -i : i;
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if (j & (j-1))
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while (j < 128)
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j += j;
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else
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/* Power of two. */
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j *= 128;
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q = 4.*(1<<30)*128/j;
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r = ceil (q);
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printf ("\t.long\t0x%X\n", (unsigned) r);
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err = r - q;
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if (err > max_err)
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max_err = err;
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}
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#if 0
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printf ("\t/* maximum error: %f */\n", max_err);
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#endif
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exit (0);
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}
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