1 /* catdvi - get text from DVI files
2 Copyright (C) 1999 Antti-Juhani Kaijanaho <gaia@iki.fi>
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17 */
18
19 #include "bytesex.h"
20 #include "fixword.h"
21 #include "util.h"
22
23 fix_word_t fw_remainder = 0;
24
fw2double(fix_word_t fw)25 double fw2double(fix_word_t fw)
26 {
27 return ((double) fw) / (((uint32) 1) << FW_FRACTION_BIT);
28 }
29
30
fw_prod(fix_word_t a,fix_word_t b)31 fix_word_t fw_prod(fix_word_t a, fix_word_t b)
32 {
33 fix_word_t al, bl;
34
35 if (a < 0) return - fw_prod(-a, b);
36 if (b < 0) return - fw_prod(a, -b);
37
38 /* We have to compute a*b >> 20 without overflowing 32 bits */
39 al = a & 32767;
40 bl = b & 32767;
41 a >>= 15;
42 b >>= 15;
43
44 return (((al*bl >> 15) + a*bl + al*b) >> 5) + (a*b << 10);
45 }
46