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 void
  31 engine_init (SIM_DESC sd)
  32 {
  33   memset (&STATE_CPU (sd, 0)->reg, 0, sizeof STATE_CPU (sd, 0)->reg);
  34   memset (&STATE_CPU (sd, 0)->cia, 0, sizeof STATE_CPU (sd, 0)->cia);
  35   CPU_STATE (STATE_CPU (sd, 0)) = sd;
  36 }
  37
  38
  39 /* Mechanisms for stopping/restarting the simulation */
  40
  41 void
  42 engine_error (SIM_DESC sd,
  43               sim_cpu *cpu,
  44               instruction_address cia,
  45               const char *fmt,
  46               ...)
  47 {
  48   va_list ap;
  49   va_start (ap, fmt);
  50   sim_io_evprintf (sd, fmt, ap);
  51   va_end (ap);
  52
  53   if (sd->halt_ok)
  54     {
  55       sim_io_eprintf (sd, "\n");
  56       engine_halt (sd, cpu, cia, sim_signalled, SIGABRT);
  57     }
  58   else
  59     sim_io_error (sd, " - aborting simulation");
  60 }
  61
  62 void
  63 engine_halt (SIM_DESC sd,
  64              sim_cpu *cpu,
  65              instruction_address cia,
  66              enum sim_stop reason,
  67              int siggnal)
  68 {
  69   if (!sd->halt_ok)
  70     sim_io_error (sd, "engine_halt - bad longjmp");
  71   sd->reason = reason;
  72   sd->siggnal = siggnal;
  73   sd->halt_ok = 0;
  74   sd->restart_ok = 0;
  75   if (cpu != NULL)
  76     cpu->cia = cia;
  77   longjmp (sd->path_to_halt, 1);
  78 }
  79
  80 void
  81 engine_restart (SIM_DESC sd,
  82                 sim_cpu *cpu,
  83                 instruction_address cia)
  84 {
  85   if (!sd->restart_ok)
  86     sim_io_error (sd, "engine_restart - bad longjmp");
  87   sd->restart_ok = 0;
  88   cpu->cia = cia;
  89   longjmp(sd->path_to_restart, 1);
  90 }
  91
  92
  93 void
  94 engine_run_until_stop (SIM_DESC sd,
  95                        volatile int *keep_running)
  96 {
  97   if (!setjmp (sd->path_to_halt))
  98     {
  99       instruction_address cia;
 100       sim_cpu *cpu = STATE_CPU (sd, 0);
 101       sd->halt_ok = 1;
 102       setjmp (sd->path_to_restart);
 103       sd->restart_ok = 1;
 104       cia = cpu->cia;
 105       do
 106         {
 107           if (cia.ip == -1)
 108             {
 109               /* anulled instruction */
 110               cia.ip = cia.dp;
 111               cia.dp = cia.dp + sizeof (instruction_word);
 112             }
 113           else
 114             {
 115               instruction_word insn = IMEM (cia.ip);
 116               cia = idecode_issue (sd, insn, cia);
 117             }
 118         }
 119       while (*keep_running);
 120       engine_halt (sd, cpu, cia, sim_stopped, SIGINT);
 121     }
 122 }