1 /* This testcase is part of GDB, the GNU debugger. 2 3 Copyright 2017-2024 Free Software Foundation, Inc. 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation; either version 3 of the License, or 8 (at your option) any later version. 9 10 This program 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 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 17 18 #include <stdint.h> 19 #include <assert.h> 20 21 static int again; 22 23 static volatile struct 24 { 25 uint64_t alignment; 26 union 27 { 28 uint64_t size8[1]; 29 uint32_t size4[2]; 30 uint16_t size2[4]; 31 uint8_t size1[8]; 32 uint64_t size8twice[3]; 33 } 34 u; 35 } data; 36 37 static int size = 0; 38 static int offset; 39 40 static void 41 write_size8twice (void) 42 { 43 static const uint64_t first = 1; 44 static const uint64_t second = 2; 45 46 #ifdef __aarch64__ 47 volatile void *p = &data.u.size8twice[offset]; 48 asm volatile ("stp %1, %2, [%0]" 49 : /* output */ 50 : "r" (p), "r" (first), "r" (second) /* input */ 51 : "memory" /* clobber */); 52 #else 53 data.u.size8twice[offset] = first; 54 data.u.size8twice[offset + 1] = second; 55 #endif 56 } 57 58 int 59 main (void) 60 { 61 volatile uint64_t local; 62 63 assert (sizeof (data) == 8 + 3 * 8); 64 65 write_size8twice (); 66 67 while (size) 68 { 69 switch (size) 70 { 71 /* __s390x__ also defines __s390__ */ 72 #ifdef __s390__ 73 # define ACCESS(var) var = ~var 74 #else 75 # define ACCESS(var) local = var 76 #endif 77 case 8: 78 ACCESS (data.u.size8[offset]); 79 break; 80 case 4: 81 ACCESS (data.u.size4[offset]); 82 break; 83 case 2: 84 ACCESS (data.u.size2[offset]); 85 break; 86 case 1: 87 ACCESS (data.u.size1[offset]); 88 break; 89 #undef ACCESS 90 default: 91 assert (0); 92 } 93 size = 0; 94 size = size; /* start_again */ 95 } 96 return 0; /* final_return */ 97 } 98