sim/tic80/interp.c

   1 /*  This file is part of the GDB simulators.
   2
   3     Copyright (C) 1997, Free Software Foundation
   4     Condtributed by Cyngnus Solutions.
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19
  20     */
  21
  22
  23
  24 #include "sim-main.h"
  25
  26 #include "idecode.h"
  27
  28 #include <signal.h>
  29
  30 #ifdef HAVE_STRING_H
  31 #include <string.h>
  32 #else
  33 #ifdef HAVE_STRINGS_H
  34 #include <strings.h>
  35 #endif
  36 #endif
  37
  38 void
  39 engine_init (SIM_DESC sd)
  40 {
  41   memset (&STATE_CPU (sd, 0)->reg, 0, sizeof STATE_CPU (sd, 0)->reg);
  42   memset (&STATE_CPU (sd, 0)->cia, 0, sizeof STATE_CPU (sd, 0)->cia);
  43   CPU_STATE (STATE_CPU (sd, 0)) = sd;
  44 }
  45
  46
  47 /* Mechanisms for stopping/restarting the simulation */
  48
  49 void
  50 engine_error (SIM_DESC sd,
  51               sim_cpu *cpu,
  52               instruction_address cia,
  53               const char *fmt,
  54               ...)
  55 {
  56   va_list ap;
  57   va_start (ap, fmt);
  58   sim_io_evprintf (sd, fmt, ap);
  59   va_end (ap);
  60
  61   if (sd->halt_ok)
  62     {
  63       sim_io_eprintf (sd, "\n");
  64       engine_halt (sd, cpu, cia, sim_signalled, SIGABRT);
  65     }
  66   else
  67     sim_io_error (sd, " - aborting simulation");
  68 }
  69
  70 void
  71 engine_halt (SIM_DESC sd,
  72              sim_cpu *cpu,
  73              instruction_address cia,
  74              enum sim_stop reason,
  75              int siggnal)
  76 {
  77   if (!sd->halt_ok)
  78     sim_io_error (sd, "engine_halt - bad longjmp");
  79   sd->reason = reason;
  80   sd->siggnal = siggnal;
  81   sd->halt_ok = 0;
  82   sd->restart_ok = 0;
  83   if (cpu != NULL)
  84     cpu->cia = cia;
  85   longjmp (sd->path_to_halt, 1);
  86 }
  87
  88 void
  89 engine_restart (SIM_DESC sd,
  90                 sim_cpu *cpu,
  91                 instruction_address cia)
  92 {
  93   if (!sd->restart_ok)
  94     sim_io_error (sd, "engine_restart - bad longjmp");
  95   sd->restart_ok = 0;
  96   cpu->cia = cia;
  97   longjmp(sd->path_to_restart, 1);
  98 }
  99
 100
 101 void
 102 engine_run_until_stop (SIM_DESC sd,
 103                        volatile int *keep_running)
 104 {
 105   if (!setjmp (sd->path_to_halt))
 106     {
 107       instruction_address cia;
 108       sim_cpu *cpu = STATE_CPU (sd, 0);
 109       sd->halt_ok = 1;
 110       setjmp (sd->path_to_restart);
 111       sd->restart_ok = 1;
 112       cia = cpu->cia;
 113       do
 114         {
 115           if (cia.ip == -1)
 116             {
 117               /* anulled instruction */
 118               cia.ip = cia.dp;
 119               cia.dp = cia.dp + sizeof (instruction_word);
 120             }
 121           else
 122             {
 123               instruction_word insn = IMEM (cia.ip);
 124               cia = idecode_issue (sd, insn, cia);
 125             }
 126         }
 127       while (*keep_running);
 128       engine_halt (sd, cpu, cia, sim_stopped, SIGINT);
 129     }
 130 }