| 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 | |
| 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 | |
| 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 | } |