sim/common/sim-events.h

   1 /* The common simulator framework for GDB, the GNU Debugger.
   2
   3    Copyright 2002-2023 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 #include <stdarg.h>
  27
  28 #include "ansidecl.h"
  29
  30 /* Notes:
  31
  32    When scheduling an event, the a delta of zero/one refers to the
  33    timeline as follows:
  34
  35    epoch   0|1              1|2              2|3              3|
  36    **queue**|--insn--|*queue*|--insn--|*queue*|--insn--|*queue*|
  37      |   ^               ^        |       ^                ^
  38      `- +0 ------------ +1 --..   `----- +0 ------------- +1 --..
  39
  40    When the queue is initialized, the time is set to zero with a
  41    number of initialization events scheduled.  Consequently, as also
  42    illustrated above, the event queue should be processed before the
  43    first instruction.  That instruction being executed during tick 1.
  44
  45    The simulator main loop may take a form similar to:
  46
  47        if (halt-/restart-setjmp)
  48          {
  49
  50            .... // Determine who should go next
  51            last-cpu-nr = get-last-cpu-nr (sd);
  52            next-cpu-nr = get-next-cpu-nr (sd);
  53            events-were-last? = (last-cpu-nr >= nr-cpus);
  54            events-were-next? = (next-cpu-nr >= nr-cpus);
  55
  56            .... // process any outstanding events
  57            sim_events_preprocess (sd, events-were-last?, events-were-next?);
  58            if (events-were-next)
  59              next-cpu-nr = 0;
  60
  61            .... // prime main loop
  62
  63            while (1)
  64              {
  65                 .... // model one insn of next-cpu-nr .. nr-cpus
  66                 if (sim_events_tick (sd))
  67                   sim_events_process (sd);
  68                 next-cpu-nr = 0
  69              }
  70          }
  71
  72    NB.  In the above pseudo code it is assumed that any cpu-nr >=
  73    nr-cpus is a marker for the event queue. */
  74
  75
  76 typedef void sim_event_handler(SIM_DESC sd, void *data);
  77
  78 typedef struct _sim_event sim_event;
  79
  80 typedef struct _sim_events sim_events;
  81 struct _sim_events {
  82   int nr_ticks_to_process;
  83   sim_event *queue;
  84   sim_event *watchpoints;
  85   sim_event *watchedpoints;
  86   sim_event *free_list;
  87   /* flag additional work needed */
  88   volatile int work_pending;
  89   /* the asynchronous event queue */
  90 #ifndef MAX_NR_SIGNAL_SIM_EVENTS
  91 #define MAX_NR_SIGNAL_SIM_EVENTS 2
  92 #endif
  93   sim_event *held;
  94   volatile int nr_held;
  95   /* timekeeping */
  96   unsigned long elapsed_wallclock;
  97   SIM_ELAPSED_TIME resume_wallclock;
  98   int64_t time_of_event;
  99   int64_t time_from_event;
 100 };
 101
 102
 103
 104 /* Install the "events" module.  */
 105
 106 extern SIM_RC sim_events_install (SIM_DESC sd);
 107
 108
 109 /* Schedule an event DELTA_TIME ticks into the future */
 110
 111 extern sim_event *sim_events_schedule
 112 (SIM_DESC sd,
 113  int64_t delta_time,
 114  sim_event_handler *handler,
 115  void *data);
 116
 117 extern sim_event *sim_events_schedule_tracef
 118 (SIM_DESC sd,
 119  int64_t delta_time,
 120  sim_event_handler *handler,
 121  void *data,
 122  const char *fmt,
 123  ...) ATTRIBUTE_NULL_PRINTF (5, 6);
 124
 125 extern sim_event *sim_events_schedule_vtracef
 126 (SIM_DESC sd,
 127  int64_t delta_time,
 128  sim_event_handler *handler,
 129  void *data,
 130  const char *fmt,
 131  va_list ap) ATTRIBUTE_NULL_PRINTF (5, 0);
 132
 133
 134 extern void sim_events_schedule_after_signal
 135 (SIM_DESC sd,
 136  int64_t delta_time,
 137  sim_event_handler *handler,
 138  void *data);
 139
 140 /* NB: signal level events can't have trace strings as malloc isn't
 141    available */
 142
 143
 144
 145 /* Schedule an event milli-seconds from NOW.  The exact interpretation
 146    of wallclock is host dependant. */
 147
 148 extern sim_event *sim_events_watch_clock
 149 (SIM_DESC sd,
 150  unsigned delta_ms_time,
 151  sim_event_handler *handler,
 152  void *data);
 153
 154
 155 /* Schedule an event when a PC matches a range.  */
 156
 157 extern sim_event *sim_events_watch_pc
 158 (SIM_DESC sd,
 159  int is_within,
 160  uint64_t lb,
 161  uint64_t ub,
 162  sim_event_handler *handler,
 163  void *data);
 164
 165
 166 /* Schedule an event when the test (IS_WITHIN == (VAL >= LB && VAL <=
 167    UB)) of the NR_BYTES value at HOST_ADDR with BYTE_ORDER endian is
 168    true.
 169
 170    HOST_ADDR: pointer into the host address space.
 171    BYTE_ORDER: BFD_ENDIAN_UNKNOWN - host endian; BFD_ENDIAN_BIG;
 172                BFD_ENDIAN_LITTLE.  */
 173
 174 extern sim_event *sim_events_watch_sim
 175 (SIM_DESC sd,
 176  void *host_addr,
 177  int nr_bytes,
 178  enum bfd_endian byte_order,
 179  int is_within,
 180  uint64_t lb,
 181  uint64_t ub,
 182  sim_event_handler *handler,
 183  void *data);
 184
 185
 186 /* Schedule an event when the test (IS_WITHIN == (VAL >= LB && VAL <=
 187    UB)) of the NR_BYTES value at CORE_ADDR in BYTE_ORDER endian is
 188    true.
 189
 190    CORE_ADDR/MAP: pointer into the target address space.
 191    BYTE_ORDER: BFD_ENDIAN_UNKNOWN - host endian; BFD_ENDIAN_BIG;
 192                BFD_ENDIAN_LITTLE.  */
 193
 194 extern sim_event *sim_events_watch_core
 195 (SIM_DESC sd,
 196  address_word core_addr,
 197  unsigned map,
 198  int nr_bytes,
 199  enum bfd_endian byte_order,
 200  int is_within,
 201  uint64_t lb,
 202  uint64_t ub,
 203  sim_event_handler *handler,
 204  void *data);
 205
 206 /* Deschedule the specified event */
 207
 208 extern void sim_events_deschedule
 209 (SIM_DESC sd,
 210  sim_event *event_to_remove);
 211
 212
 213 /* Prepare for main simulator loop.  Ensure that the next thing to do
 214    is not event processing.
 215
 216    If the simulator halted part way through event processing then both
 217    EVENTS_WERE_LAST and EVENTS_WERE_NEXT shall be true.
 218
 219    If the simulator halted after processing the last cpu, then only
 220    EVENTS_WERE_NEXT shall be true. */
 221
 222 INLINE_SIM_EVENTS\
 223 (void) sim_events_preprocess
 224 (SIM_DESC sd,
 225  int events_were_last,
 226  int events_were_next);
 227
 228
 229 /* Progress time.
 230
 231    Separated into two parts so that the main loop can save its context
 232    before the event queue is processed.  When sim_events_tick*()
 233    returns true, any simulation context should be saved and
 234    sim_events_process() called.
 235
 236    SIM_EVENTS_TICK advances the clock by 1 cycle.
 237
 238    SIM_EVENTS_TICKN advances the clock by N cycles (1..MAXINT). */
 239
 240 INLINE_SIM_EVENTS\
 241 (int) sim_events_tick
 242 (SIM_DESC sd);
 243
 244 INLINE_SIM_EVENTS\
 245 (int) sim_events_tickn
 246 (SIM_DESC sd,
 247  int n);
 248
 249 INLINE_SIM_EVENTS\
 250 (void) sim_events_process
 251 (SIM_DESC sd);
 252
 253
 254 /* Advance the clock by an additional SLIP cycles at the next call to
 255    sim_events_tick*().  For multiple calls, the effect is
 256    accumulative. */
 257
 258 INLINE_SIM_EVENTS\
 259 (void) sim_events_slip
 260 (SIM_DESC sd,
 261  int slip);
 262
 263
 264 /* Progress time such that an event shall occur upon the next call to
 265    sim_events tick */
 266
 267 #if 0
 268 INLINE_SIM_EVENTS\
 269 (void) sim_events_timewarp
 270 (SIM_DESC sd);
 271 #endif
 272
 273
 274 /* local concept of elapsed target time */
 275
 276 INLINE_SIM_EVENTS\
 277 (int64_t) sim_events_time
 278 (SIM_DESC sd);
 279
 280
 281 /* local concept of elapsed host time (milliseconds) */
 282
 283 INLINE_SIM_EVENTS\
 284 (unsigned long) sim_events_elapsed_time
 285 (SIM_DESC sd);
 286
 287 /* Returns the time that remains before the event is raised. */
 288 INLINE_SIM_EVENTS\
 289 (int64_t) sim_events_remain_time
 290 (SIM_DESC sd, sim_event *event);
 291
 292
 293 #endif