1 /*
2 * Copyright(c) 2022-2023 Qualcomm Innovation Center, Inc. All Rights Reserved.
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, see <http://www.gnu.org/licenses/>.
16 */
17
18 /*
19 * Test the VLIW semantics of exceptions with mem_noshuf
20 *
21 * When a packet has the :mem_noshuf attribute, the semantics dictate
22 * That the load will get the data from the store if the addresses overlap.
23 * To accomplish this, we perform the store first. However, we have to
24 * handle the case where the store raises an exception. In that case, the
25 * store should not alter the machine state.
26 *
27 * We test this with a mem_noshuf packet with a store to a global variable,
28 * "should_not_change" and a load from NULL. After the SIGSEGV is caught,
29 * we check * that the "should_not_change" value is the same.
30 *
31 * We also check that a predicated load where the predicate is false doesn't
32 * raise an exception and allows the store to happen.
33 */
34
35 #include <stdlib.h>
36 #include <stdio.h>
37 #include <stdint.h>
38 #include <stdbool.h>
39 #include <unistd.h>
40 #include <sys/types.h>
41 #include <fcntl.h>
42 #include <setjmp.h>
43 #include <signal.h>
44
45 int err;
46
47 #include "hex_test.h"
48
49 bool segv_caught;
50
51 #define SHOULD_NOT_CHANGE_VAL 5
52 int32_t should_not_change = SHOULD_NOT_CHANGE_VAL;
53
54 #define OK_TO_CHANGE_VAL 13
55 int32_t ok_to_change = OK_TO_CHANGE_VAL;
56
57 jmp_buf jmp_env;
58
sig_segv(int sig,siginfo_t * info,void * puc)59 static void sig_segv(int sig, siginfo_t *info, void *puc)
60 {
61 check32(sig, SIGSEGV);
62 segv_caught = true;
63 longjmp(jmp_env, 1);
64 }
65
main()66 int main()
67 {
68 struct sigaction act;
69 int32_t dummy32;
70 int64_t dummy64;
71 void *p;
72
73 /* SIGSEGV test */
74 act.sa_sigaction = sig_segv;
75 sigemptyset(&act.sa_mask);
76 act.sa_flags = SA_SIGINFO;
77 chk_error(sigaction(SIGSEGV, &act, NULL));
78 if (setjmp(jmp_env) == 0) {
79 asm volatile("r18 = ##should_not_change\n\t"
80 "r19 = #0\n\t"
81 "{\n\t"
82 " memw(r18) = #7\n\t"
83 " %0 = memw(r19)\n\t"
84 "}:mem_noshuf\n\t"
85 : "=r"(dummy32) : : "r18", "r19", "memory");
86 }
87
88 act.sa_handler = SIG_DFL;
89 sigemptyset(&act.sa_mask);
90 act.sa_flags = 0;
91 chk_error(sigaction(SIGSEGV, &act, NULL));
92
93 check32(segv_caught, true);
94 check32(should_not_change, SHOULD_NOT_CHANGE_VAL);
95
96 /*
97 * Check that a predicated load where the predicate is false doesn't
98 * raise an exception and allows the store to happen.
99 */
100 asm volatile("r18 = ##ok_to_change\n\t"
101 "r19 = #0\n\t"
102 "p0 = cmp.gt(r0, r0)\n\t"
103 "{\n\t"
104 " memw(r18) = #7\n\t"
105 " if (p0) %0 = memw(r19)\n\t"
106 "}:mem_noshuf\n\t"
107 : "=r"(dummy32) : : "r18", "r19", "p0", "memory");
108
109 check32(ok_to_change, 7);
110
111 /*
112 * Also check that the post-increment doesn't happen when the
113 * predicate is false.
114 */
115 ok_to_change = OK_TO_CHANGE_VAL;
116 p = NULL;
117 asm volatile("r18 = ##ok_to_change\n\t"
118 "p0 = cmp.gt(r0, r0)\n\t"
119 "{\n\t"
120 " memw(r18) = #9\n\t"
121 " if (p0) %1 = memd(%0 ++ #8)\n\t"
122 "}:mem_noshuf\n\t"
123 : "+r"(p), "=r"(dummy64) : : "r18", "p0", "memory");
124
125 check32(ok_to_change, 9);
126 check32((int)p, (int)NULL);
127
128 puts(err ? "FAIL" : "PASS");
129 return err ? EXIT_FAILURE : EXIT_SUCCESS;
130 }
131