File Coverage

src/int/i15_mulacc.c
Criterion Covered Total %
statement 0 15 0.0
branch 0 4 0.0
condition n/a
subroutine n/a
pod n/a
total 0 19 0.0


line stmt bran cond sub pod time code
1             /*
2             * Copyright (c) 2017 Thomas Pornin
3             *
4             * Permission is hereby granted, free of charge, to any person obtaining
5             * a copy of this software and associated documentation files (the
6             * "Software"), to deal in the Software without restriction, including
7             * without limitation the rights to use, copy, modify, merge, publish,
8             * distribute, sublicense, and/or sell copies of the Software, and to
9             * permit persons to whom the Software is furnished to do so, subject to
10             * the following conditions:
11             *
12             * The above copyright notice and this permission notice shall be
13             * included in all copies or substantial portions of the Software.
14             *
15             * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16             * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17             * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18             * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19             * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20             * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21             * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22             * SOFTWARE.
23             */
24              
25             #include "inner.h"
26              
27             /* see inner.h */
28             void
29 0           br_i15_mulacc(uint16_t *d, const uint16_t *a, const uint16_t *b)
30             {
31             size_t alen, blen, u;
32             unsigned dl, dh;
33              
34 0           alen = (a[0] + 15) >> 4;
35 0           blen = (b[0] + 15) >> 4;
36              
37             /*
38             * Announced bit length of d[] will be the sum of the announced
39             * bit lengths of a[] and b[]; but the lengths are encoded.
40             */
41 0           dl = (a[0] & 15) + (b[0] & 15);
42 0           dh = (a[0] >> 4) + (b[0] >> 4);
43 0           d[0] = (dh << 4) + dl + (~(uint32_t)(dl - 15) >> 31);
44              
45 0 0         for (u = 0; u < blen; u ++) {
46             uint32_t f;
47             size_t v;
48             uint32_t cc;
49              
50 0           f = b[1 + u];
51 0           cc = 0;
52 0 0         for (v = 0; v < alen; v ++) {
53             uint32_t z;
54              
55 0           z = (uint32_t)d[1 + u + v] + MUL15(f, a[1 + v]) + cc;
56 0           cc = z >> 15;
57 0           d[1 + u + v] = z & 0x7FFF;
58             }
59 0           d[1 + u + alen] = cc;
60             }
61 0           }