1 /*
2 * Copyright (c) 2000, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 #include "AlphaMath.h"
27
28 unsigned char mul8table[256][256];
29 unsigned char div8table[256][256];
30
initAlphaTables()31 void initAlphaTables()
32 {
33 unsigned int i;
34 unsigned int j;
35
36 for (i = 1; i < 256; i++) { /* SCALE == (1 << 24) */
37 int inc = (i << 16) + (i<<8) + i; /* approx. SCALE * (i/255.0) */
38 int val = inc + (1 << 23); /* inc + SCALE*0.5 */
39 for (j = 1; j < 256; j++) {
40 mul8table[i][j] = (val >> 24); /* val / SCALE */
41 val += inc;
42 }
43 }
44
45 for (i = 1; i < 256; i++) {
46 unsigned int inc;
47 unsigned int val;
48 inc = 0xff;
49 inc = ((inc << 24) + i/2) / i;
50 val = (1 << 23);
51 for (j = 0; j < i; j++) {
52 div8table[i][j] = (val >> 24);
53 val += inc;
54 }
55 for (j = i; j < 256; j++) {
56 div8table[i][j] = 255;
57 }
58 }
59 }
60