sim/common/sim-events.h

   1 /* The common simulator framework for GDB, the GNU Debugger.
   2
   3    Copyright 2002-2021 Free Software Foundation, Inc.
   4
   5    Contributed by Andrew Cagney and Red Hat.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22
  23 #ifndef SIM_EVENTS_H
  24 #define SIM_EVENTS_H
  25
  26
  27 /* Notes:
  28
  29    When scheduling an event, the a delta of zero/one refers to the
  30    timeline as follows:
  31
  32    epoch   0|1              1|2              2|3              3|
  33    **queue**|--insn--|*queue*|--insn--|*queue*|--insn--|*queue*|
  34      |   ^               ^        |       ^                ^
  35      `- +0 ------------ +1 --..   `----- +0 ------------- +1 --..
  36
  37    When the queue is initialized, the time is set to zero with a
  38    number of initialization events scheduled.  Consequently, as also
  39    illustrated above, the event queue should be processed before the
  40    first instruction.  That instruction being executed during tick 1.
  41
  42    The simulator main loop may take a form similar to:
  43
  44        if (halt-/restart-setjmp)
  45          {
  46
  47            .... // Determine who should go next
  48            last-cpu-nr = get-last-cpu-nr (sd);
  49            next-cpu-nr = get-next-cpu-nr (sd);
  50            events-were-last? = (last-cpu-nr >= nr-cpus);
  51            events-were-next? = (next-cpu-nr >= nr-cpus);
  52
  53            .... // process any outstanding events
  54            sim_events_preprocess (sd, events-were-last?, events-were-next?);
  55            if (events-were-next)
  56              next-cpu-nr = 0;
  57
  58            .... // prime main loop
  59
  60            while (1)
  61              {
  62                 .... // model one insn of next-cpu-nr .. nr-cpus
  63                 if (sim_events_tick (sd))
  64                   sim_events_process (sd);
  65                 next-cpu-nr = 0
  66              }
  67          }
  68
  69    NB.  In the above pseudo code it is assumed that any cpu-nr >=
  70    nr-cpus is a marker for the event queue. */
  71
  72
  73 typedef void sim_event_handler(SIM_DESC sd, void *data);
  74
  75 typedef struct _sim_event sim_event;
  76
  77 typedef struct _sim_events sim_events;
  78 struct _sim_events {
  79   int nr_ticks_to_process;
  80   sim_event *queue;
  81   sim_event *watchpoints;
  82   sim_event *watchedpoints;
  83   sim_event *free_list;
  84   /* flag additional work needed */
  85   volatile int work_pending;
  86   /* the asynchronous event queue */
  87 #ifndef MAX_NR_SIGNAL_SIM_EVENTS
  88 #define MAX_NR_SIGNAL_SIM_EVENTS 2
  89 #endif
  90   sim_event *held;
  91   volatile int nr_held;
  92   /* timekeeping */
  93   unsigned long elapsed_wallclock;
  94   SIM_ELAPSED_TIME resume_wallclock;
  95   signed64 time_of_event;
  96   signed64 time_from_event;
  97 };
  98
  99
 100
 101 /* Install the "events" module.  */
 102
 103 extern SIM_RC sim_events_install (SIM_DESC sd);
 104
 105
 106 /* Schedule an event DELTA_TIME ticks into the future */
 107
 108 extern sim_event *sim_events_schedule
 109 (SIM_DESC sd,
 110  signed64 delta_time,
 111  sim_event_handler *handler,
 112  void *data);
 113
 114 extern sim_event *sim_events_schedule_tracef
 115 (SIM_DESC sd,
 116  signed64 delta_time,
 117  sim_event_handler *handler,
 118  void *data,
 119  const char *fmt,
 120  ...) ATTRIBUTE_NULL_PRINTF (5, 6);
 121
 122 extern sim_event *sim_events_schedule_vtracef
 123 (SIM_DESC sd,
 124  signed64 delta_time,
 125  sim_event_handler *handler,
 126  void *data,
 127  const char *fmt,
 128  va_list ap) ATTRIBUTE_NULL_PRINTF (5, 0);
 129
 130
 131 extern void sim_events_schedule_after_signal
 132 (SIM_DESC sd,
 133  signed64 delta_time,
 134  sim_event_handler *handler,
 135  void *data);
 136
 137 /* NB: signal level events can't have trace strings as malloc isn't
 138    available */
 139
 140
 141
 142 /* Schedule an event milli-seconds from NOW.  The exact interpretation
 143    of wallclock is host dependant. */
 144
 145 extern sim_event *sim_events_watch_clock
 146 (SIM_DESC sd,
 147  unsigned delta_ms_time,
 148  sim_event_handler *handler,
 149  void *data);
 150
 151
 152 /* Schedule an event when a PC matches a range.  */
 153
 154 extern sim_event *sim_events_watch_pc
 155 (SIM_DESC sd,
 156  int is_within,
 157  unsigned64 lb,
 158  unsigned64 ub,
 159  sim_event_handler *handler,
 160  void *data);
 161
 162
 163 /* Schedule an event when the test (IS_WITHIN == (VAL >= LB && VAL <=
 164    UB)) of the NR_BYTES value at HOST_ADDR with BYTE_ORDER endian is
 165    true.
 166
 167    HOST_ADDR: pointer into the host address space.
 168    BYTE_ORDER: BFD_ENDIAN_UNKNOWN - host endian; BFD_ENDIAN_BIG;
 169                BFD_ENDIAN_LITTLE.  */
 170
 171 extern sim_event *sim_events_watch_sim
 172 (SIM_DESC sd,
 173  void *host_addr,
 174  int nr_bytes,
 175  enum bfd_endian byte_order,
 176  int is_within,
 177  unsigned64 lb,
 178  unsigned64 ub,
 179  sim_event_handler *handler,
 180  void *data);
 181
 182
 183 /* Schedule an event when the test (IS_WITHIN == (VAL >= LB && VAL <=
 184    UB)) of the NR_BYTES value at CORE_ADDR in BYTE_ORDER endian is
 185    true.
 186
 187    CORE_ADDR/MAP: pointer into the target address space.
 188    BYTE_ORDER: BFD_ENDIAN_UNKNOWN - host endian; BFD_ENDIAN_BIG;
 189                BFD_ENDIAN_LITTLE.  */
 190
 191 extern sim_event *sim_events_watch_core
 192 (SIM_DESC sd,
 193  address_word core_addr,
 194  unsigned map,
 195  int nr_bytes,
 196  enum bfd_endian byte_order,
 197  int is_within,
 198  unsigned64 lb,
 199  unsigned64 ub,
 200  sim_event_handler *handler,
 201  void *data);
 202
 203 /* Deschedule the specified event */
 204
 205 extern void sim_events_deschedule
 206 (SIM_DESC sd,
 207  sim_event *event_to_remove);
 208
 209
 210 /* Prepare for main simulator loop.  Ensure that the next thing to do
 211    is not event processing.
 212
 213    If the simulator halted part way through event processing then both
 214    EVENTS_WERE_LAST and EVENTS_WERE_NEXT shall be true.
 215
 216    If the simulator halted after processing the last cpu, then only
 217    EVENTS_WERE_NEXT shall be true. */
 218
 219 INLINE_SIM_EVENTS\
 220 (void) sim_events_preprocess
 221 (SIM_DESC sd,
 222  int events_were_last,
 223  int events_were_next);
 224
 225
 226 /* Progress time.
 227
 228    Separated into two parts so that the main loop can save its context
 229    before the event queue is processed.  When sim_events_tick*()
 230    returns true, any simulation context should be saved and
 231    sim_events_process() called.
 232
 233    SIM_EVENTS_TICK advances the clock by 1 cycle.
 234
 235    SIM_EVENTS_TICKN advances the clock by N cycles (1..MAXINT). */
 236
 237 INLINE_SIM_EVENTS\
 238 (int) sim_events_tick
 239 (SIM_DESC sd);
 240
 241 INLINE_SIM_EVENTS\
 242 (int) sim_events_tickn
 243 (SIM_DESC sd,
 244  int n);
 245
 246 INLINE_SIM_EVENTS\
 247 (void) sim_events_process
 248 (SIM_DESC sd);
 249
 250
 251 /* Advance the clock by an additional SLIP cycles at the next call to
 252    sim_events_tick*().  For multiple calls, the effect is
 253    accumulative. */
 254
 255 INLINE_SIM_EVENTS\
 256 (void) sim_events_slip
 257 (SIM_DESC sd,
 258  int slip);
 259
 260
 261 /* Progress time such that an event shall occur upon the next call to
 262    sim_events tick */
 263
 264 #if 0
 265 INLINE_SIM_EVENTS\
 266 (void) sim_events_timewarp
 267 (SIM_DESC sd);
 268 #endif
 269
 270
 271 /* local concept of elapsed target time */
 272
 273 INLINE_SIM_EVENTS\
 274 (signed64) sim_events_time
 275 (SIM_DESC sd);
 276
 277
 278 /* local concept of elapsed host time (milliseconds) */
 279
 280 INLINE_SIM_EVENTS\
 281 (unsigned long) sim_events_elapsed_time
 282 (SIM_DESC sd);
 283
 284 /* Returns the time that remains before the event is raised. */
 285 INLINE_SIM_EVENTS\
 286 (signed64) sim_events_remain_time
 287 (SIM_DESC sd, sim_event *event);
 288
 289
 290 #endif