1 /* Example synacor simulator. 2 3 Copyright (C) 2005-2024 Free Software Foundation, Inc. 4 Contributed by Mike Frysinger. 5 6 This file is part of simulators. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 3 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 20 21 /* This file contains the main glue logic between the sim core and the target 22 specific simulator. Normally this file will be kept small and the target 23 details will live in other files. 24 25 For more specific details on these functions, see the sim/sim.h header 26 file. */ 27 28 /* This must come before any other includes. */ 29 #include "defs.h" 30 31 #include "sim/callback.h" 32 #include "sim-main.h" 33 #include "sim-options.h" 34 35 #include "example-synacor-sim.h" 36 37 /* This function is the main loop. It should process ticks and decode+execute 38 a single instruction. 39 40 Usually you do not need to change things here. */ 41 42 void 43 sim_engine_run (SIM_DESC sd, 44 int next_cpu_nr, /* ignore */ 45 int nr_cpus, /* ignore */ 46 int siggnal) /* ignore */ 47 { 48 SIM_CPU *cpu; 49 50 SIM_ASSERT (STATE_MAGIC (sd) == SIM_MAGIC_NUMBER); 51 52 cpu = STATE_CPU (sd, 0); 53 54 while (1) 55 { 56 step_once (cpu); 57 if (sim_events_tick (sd)) 58 sim_events_process (sd); 59 } 60 } 61 62 /* Initialize the simulator from scratch. This is called once per lifetime of 63 the simulation. Think of it as a processor reset. 64 65 Usually all cpu-specific setup is handled in the initialize_cpu callback. 66 If you want to do cpu-independent stuff, then it should go at the end (see 67 where memory is initialized). */ 68 69 #define DEFAULT_MEM_SIZE (16 * 1024 * 1024) 70 71 static void 72 free_state (SIM_DESC sd) 73 { 74 if (STATE_MODULES (sd) != NULL) 75 sim_module_uninstall (sd); 76 sim_cpu_free_all (sd); 77 sim_state_free (sd); 78 } 79 80 SIM_DESC 81 sim_open (SIM_OPEN_KIND kind, host_callback *callback, 82 struct bfd *abfd, char * const *argv) 83 { 84 char c; 85 int i; 86 SIM_DESC sd = sim_state_alloc (kind, callback); 87 88 /* Set default options before parsing user options. */ 89 current_alignment = STRICT_ALIGNMENT; 90 current_target_byte_order = BFD_ENDIAN_LITTLE; 91 92 /* The cpu data is kept in a separately allocated chunk of memory. */ 93 if (sim_cpu_alloc_all_extra (sd, 0, sizeof (struct example_sim_cpu)) 94 != SIM_RC_OK) 95 { 96 free_state (sd); 97 return 0; 98 } 99 100 if (sim_pre_argv_init (sd, argv[0]) != SIM_RC_OK) 101 { 102 free_state (sd); 103 return 0; 104 } 105 106 /* XXX: Default to the Virtual environment. */ 107 if (STATE_ENVIRONMENT (sd) == ALL_ENVIRONMENT) 108 STATE_ENVIRONMENT (sd) = VIRTUAL_ENVIRONMENT; 109 110 /* The parser will print an error message for us, so we silently return. */ 111 if (sim_parse_args (sd, argv) != SIM_RC_OK) 112 { 113 free_state (sd); 114 return 0; 115 } 116 117 /* Check for/establish the a reference program image. */ 118 if (sim_analyze_program (sd, STATE_PROG_FILE (sd), abfd) != SIM_RC_OK) 119 { 120 free_state (sd); 121 return 0; 122 } 123 124 /* Establish any remaining configuration options. */ 125 if (sim_config (sd) != SIM_RC_OK) 126 { 127 free_state (sd); 128 return 0; 129 } 130 131 if (sim_post_argv_init (sd) != SIM_RC_OK) 132 { 133 free_state (sd); 134 return 0; 135 } 136 137 /* CPU specific initialization. */ 138 for (i = 0; i < MAX_NR_PROCESSORS; ++i) 139 { 140 SIM_CPU *cpu = STATE_CPU (sd, i); 141 142 initialize_cpu (sd, cpu); 143 } 144 145 /* Allocate external memory if none specified by user. 146 Use address 4 here in case the user wanted address 0 unmapped. */ 147 if (sim_core_read_buffer (sd, NULL, read_map, &c, 4, 1) == 0) 148 sim_do_commandf (sd, "memory-size %#x", DEFAULT_MEM_SIZE); 149 150 return sd; 151 } 152 153 /* Prepare to run a program that has already been loaded into memory. 154 155 Usually you do not need to change things here. */ 156 157 SIM_RC 158 sim_create_inferior (SIM_DESC sd, struct bfd *abfd, 159 char * const *argv, char * const *env) 160 { 161 SIM_CPU *cpu = STATE_CPU (sd, 0); 162 host_callback *cb = STATE_CALLBACK (sd); 163 sim_cia addr; 164 165 /* Set the PC. */ 166 if (abfd != NULL) 167 addr = bfd_get_start_address (abfd); 168 else 169 addr = 0; 170 sim_pc_set (cpu, addr); 171 172 /* Standalone mode (i.e. `run`) will take care of the argv for us in 173 sim_open() -> sim_parse_args(). But in debug mode (i.e. 'target sim' 174 with `gdb`), we need to handle it because the user can change the 175 argv on the fly via gdb's 'run'. */ 176 if (STATE_PROG_ARGV (sd) != argv) 177 { 178 freeargv (STATE_PROG_ARGV (sd)); 179 STATE_PROG_ARGV (sd) = dupargv (argv); 180 } 181 182 if (STATE_PROG_ENVP (sd) != env) 183 { 184 freeargv (STATE_PROG_ENVP (sd)); 185 STATE_PROG_ENVP (sd) = dupargv (env); 186 } 187 188 cb->argv = STATE_PROG_ARGV (sd); 189 cb->envp = STATE_PROG_ENVP (sd); 190 191 return SIM_RC_OK; 192 } 193