1 | /* Multiply a limb vector by a single limb, for PowerPC. |
2 | Copyright (C) 1993-2024 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <sysdep.h> |
20 | |
21 | /* mp_limb_t mpn_submul_1 (mp_ptr res_ptr, mp_srcptr s1_ptr, |
22 | mp_size_t s1_size, mp_limb_t s2_limb) |
23 | Calculate res-s1*s2 and put result back in res; return carry. */ |
24 | |
25 | ENTRY (__mpn_submul_1) |
26 | mtctr r5 |
27 | |
28 | lwz r0,0(r4) |
29 | mullw r7,r0,r6 |
30 | mulhwu r10,r0,r6 |
31 | lwz r9,0(r3) |
32 | subf r8,r7,r9 |
33 | addc r7,r7,r8 # invert cy (r7 is junk) |
34 | addi r3,r3,-4 # adjust res_ptr |
35 | bdz L(1) |
36 | |
37 | L(0): lwzu r0,4(r4) |
38 | stwu r8,4(r3) |
39 | mullw r8,r0,r6 |
40 | adde r7,r8,r10 |
41 | mulhwu r10,r0,r6 |
42 | lwz r9,4(r3) |
43 | addze r10,r10 |
44 | subf r8,r7,r9 |
45 | addc r7,r7,r8 # invert cy (r7 is junk) |
46 | bdnz L(0) |
47 | |
48 | L(1): stw r8,4(r3) |
49 | addze r3,r10 |
50 | blr |
51 | END (__mpn_submul_1) |
52 | |