1 /*
2 * RISC-V Emulation Helpers for QEMU.
3 *
4 * Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu
5 * Copyright (c) 2017-2018 SiFive, Inc.
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms and conditions of the GNU General Public License,
9 * version 2 or later, as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope 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 for
14 * more details.
15 *
16 * You should have received a copy of the GNU General Public License along with
17 * this program. If not, see <http://www.gnu.org/licenses/>.
18 */
19
20 #include "qemu/osdep.h"
21 #include "cpu.h"
22 #include "exec/helper-proto.h"
23
HELPER(divu_i128)24 target_ulong HELPER(divu_i128)(CPURISCVState *env,
25 target_ulong ul, target_ulong uh,
26 target_ulong vl, target_ulong vh)
27 {
28 target_ulong ql, qh;
29 Int128 q;
30
31 if (vl == 0 && vh == 0) { /* Handle special behavior on div by zero */
32 ql = ~0x0;
33 qh = ~0x0;
34 } else {
35 q = int128_divu(int128_make128(ul, uh), int128_make128(vl, vh));
36 ql = int128_getlo(q);
37 qh = int128_gethi(q);
38 }
39
40 env->retxh = qh;
41 return ql;
42 }
43
HELPER(remu_i128)44 target_ulong HELPER(remu_i128)(CPURISCVState *env,
45 target_ulong ul, target_ulong uh,
46 target_ulong vl, target_ulong vh)
47 {
48 target_ulong rl, rh;
49 Int128 r;
50
51 if (vl == 0 && vh == 0) {
52 rl = ul;
53 rh = uh;
54 } else {
55 r = int128_remu(int128_make128(ul, uh), int128_make128(vl, vh));
56 rl = int128_getlo(r);
57 rh = int128_gethi(r);
58 }
59
60 env->retxh = rh;
61 return rl;
62 }
63
HELPER(divs_i128)64 target_ulong HELPER(divs_i128)(CPURISCVState *env,
65 target_ulong ul, target_ulong uh,
66 target_ulong vl, target_ulong vh)
67 {
68 target_ulong qh, ql;
69 Int128 q;
70
71 if (vl == 0 && vh == 0) { /* Div by zero check */
72 ql = ~0x0;
73 qh = ~0x0;
74 } else if (uh == (1ULL << (TARGET_LONG_BITS - 1)) && ul == 0 &&
75 vh == ~0x0 && vl == ~0x0) {
76 /* Signed div overflow check (-2**127 / -1) */
77 ql = ul;
78 qh = uh;
79 } else {
80 q = int128_divs(int128_make128(ul, uh), int128_make128(vl, vh));
81 ql = int128_getlo(q);
82 qh = int128_gethi(q);
83 }
84
85 env->retxh = qh;
86 return ql;
87 }
88
HELPER(rems_i128)89 target_ulong HELPER(rems_i128)(CPURISCVState *env,
90 target_ulong ul, target_ulong uh,
91 target_ulong vl, target_ulong vh)
92 {
93 target_ulong rh, rl;
94 Int128 r;
95
96 if (vl == 0 && vh == 0) {
97 rl = ul;
98 rh = uh;
99 } else {
100 r = int128_rems(int128_make128(ul, uh), int128_make128(vl, vh));
101 rl = int128_getlo(r);
102 rh = int128_gethi(r);
103 }
104
105 env->retxh = rh;
106 return rl;
107 }
108