picobit-vm.c

   1 /* file: "picobit-vm.c" */
   2
   3 /*
   4  * Copyright 2004-2009 by Marc Feeley and Vincent St-Amour, All Rights Reserved.
   5  *
   6  * History:
   7  *
   8  *   15/08/2004  Release of version 1
   9  *   06/07/2008  Modified for PICOBOARD2_R3
  10  *   18/07/2008  Modified to use new object representation
  11  *   17/12/2008  Release of version 2
  12  */
  13
  14 #include "picobit-vm.h"
  15
  16 /*---------------------------------------------------------------------------*/
  17
  18 // error handling
  19
  20 #ifdef WORKSTATION
  21 void error (char *prim, char *msg) {
  22   printf ("ERROR: %s: %s\n", prim, msg);
  23   exit (1);
  24 }
  25
  26 void type_error (char *prim, char *type) {
  27   printf ("ERROR: %s: An argument of type %s was expected\n", prim, type);
  28   exit (1);
  29 }
  30 #endif
  31
  32 #ifdef SIXPIC
  33 void halt_with_error () {
  34   uart_write(101); // e
  35   uart_write(114); // r
  36   uart_write(114); // r
  37   uart_write(13);
  38   uart_write(10);
  39   exit();
  40 }
  41 #endif
  42
  43 /*---------------------------------------------------------------------------*/
  44
  45 // memory access
  46
  47 word ram_get_fieldn (obj o, word n) {
  48   switch (n) {
  49   case 0: return ram_get_field0 (o);
  50   case 1: return ram_get_field1 (o);
  51   case 2: return ram_get_field2 (o);
  52   case 3: return ram_get_field3 (o);
  53   }
  54 }
  55 void ram_set_fieldn (obj o, uint8 n, word val) { // TODO have as a macro ?
  56   switch (n) {
  57   case 0: ram_set_field0 (o, val); break;
  58   case 1: ram_set_field1 (o, val); break;
  59   case 2: ram_set_field2 (o, val); break;
  60   case 3: ram_set_field3 (o, val); break;
  61   }
  62 }
  63
  64 // these temporary variables are necessary with SIXPIC, or else the shift
  65 // results will be 8 bits values, which is wrong
  66 obj ram_get_car (obj o) {
  67   uint16 tmp = ram_get_field0 (o) & 0x1f;
  68   return (tmp << 8) | ram_get_field1 (o);
  69 }
  70 obj rom_get_car (obj o) {
  71   uint16 tmp = rom_get_field0 (o) & 0x1f;
  72   return (tmp << 8) | rom_get_field1 (o);
  73 }
  74 obj ram_get_cdr (obj o) {
  75   uint16 tmp = ram_get_field2 (o) & 0x1f;
  76   return (tmp << 8) | ram_get_field3 (o);
  77 }
  78 obj rom_get_cdr (obj o) {
  79   uint16 tmp = rom_get_field2 (o) & 0x1f;
  80   return (tmp << 8) | rom_get_field3 (o);
  81 }
  82
  83 void ram_set_car (obj o, obj val) {
  84   ram_set_field0 (o, (val >> 8) | (ram_get_field0 (o) & 0xe0));
  85   ram_set_field1 (o, val & 0xff);
  86 }
  87 void ram_set_cdr (obj o, obj val) {
  88   ram_set_field2 (o, (val >> 8) | (ram_get_field2 (o) & 0xe0));
  89   ram_set_field3 (o, val & 0xff);
  90 }
  91
  92 // function entry point
  93 // the temporary variables are necessary with SIXPIC, see above
  94 obj ram_get_entry (obj o) {
  95   uint16 tmp  = ram_get_field0 (o) & 0x1f;
  96   uint16 tmp2 = ram_get_field1 (o);
  97   return ((tmp << 11) | (tmp2 << 3) | (ram_get_field2 (o) >> 5));
  98 }
  99 obj rom_get_entry (obj o){
 100   uint16 tmp  = rom_get_field0 (o) & 0x1f;
 101   uint16 tmp2 = rom_get_field1 (o);
 102   return ((tmp << 11) | (tmp2 << 3) | (rom_get_field2 (o) >> 5));
 103 }
 104
 105 obj get_global (uint8 i) {
 106 // globals occupy the beginning of ram, with 2 globals per word
 107   if (i & 1)
 108     return ram_get_cdr (MIN_RAM_ENCODING + (i >> 1));
 109   else
 110     return ram_get_car (MIN_RAM_ENCODING + (i >> 1));
 111 }
 112 void set_global (uint8 i, obj o) {
 113   if (i & 1)
 114     ram_set_cdr (MIN_RAM_ENCODING + (i >> 1), o);
 115   else
 116     ram_set_car (MIN_RAM_ENCODING + (i >> 1), o);
 117 }
 118
 119 // TODO generic functions (get_field0, get_car, etc) that work for both rom and ram were not used, are in garbage
 120
 121 /*---------------------------------------------------------------------------*/
 122
 123 #ifdef WORKSTATION
 124
 125 int hidden_fgetc (FILE *f)
 126 {
 127   int c = fgetc (f);
 128 #if 0
 129   printf ("{%d}",c);
 130   fflush (stdout);
 131 #endif
 132   return c;
 133 }
 134
 135 #define fgetc(f) hidden_fgetc(f)
 136
 137 void write_hex_nibble (int n)
 138 {
 139   putchar ("0123456789ABCDEF"[n]);
 140 }
 141
 142 void write_hex (uint8 n)
 143 {
 144   write_hex_nibble (n >> 4);
 145   write_hex_nibble (n & 0x0f);
 146 }
 147
 148 int hex (int c)
 149 {
 150   if (c >= '0' && c <= '9')
 151     return (c - '0');
 152
 153   if (c >= 'A' && c <= 'F')
 154     return (c - 'A' + 10);
 155
 156   if (c >= 'a' && c <= 'f')
 157     return (c - 'a' + 10);
 158
 159   return -1;
 160 }
 161
 162 int read_hex_byte (FILE *f)
 163 {
 164   int h1 = hex (fgetc (f));
 165   int h2 = hex (fgetc (f));
 166
 167   if (h1 >= 0 && h2 >= 0)
 168     return (h1<<4) + h2;
 169
 170   return -1;
 171 }
 172
 173 int read_hex_file (char *filename)
 174 {
 175   int c;
 176   FILE *f = fopen (filename, "r");
 177   int result = 0;
 178   int len;
 179   int a, a1, a2;
 180   int t;
 181   int b;
 182   int i;
 183   uint8 sum;
 184   int hi16 = 0;
 185
 186   for (i=0; i<ROM_BYTES; i++)
 187     rom_mem[i] = 0xff;
 188
 189   if (f != NULL)
 190     {
 191       while ((c = fgetc (f)) != EOF)
 192         {
 193           if ((c == '\r') || (c == '\n'))
 194             continue;
 195
 196           if (c != ':' ||
 197               (len = read_hex_byte (f)) < 0 ||
 198               (a1 = read_hex_byte (f)) < 0 ||
 199               (a2 = read_hex_byte (f)) < 0 ||
 200               (t = read_hex_byte (f)) < 0)
 201             break;
 202
 203           a = (a1 << 8) + a2;
 204
 205           i = 0;
 206           sum = len + a1 + a2 + t;
 207
 208           if (t == 0)
 209             {
 210             next0:
 211
 212               if (i < len)
 213                 {
 214                   unsigned long adr = ((unsigned long)hi16 << 16) + a - CODE_START;
 215
 216                   if ((b = read_hex_byte (f)) < 0)
 217                     break;
 218
 219                   if (adr >= 0 && adr < ROM_BYTES)
 220                     rom_mem[adr] = b;
 221
 222                   a = (a + 1) & 0xffff;
 223                   i++;
 224                   sum += b;
 225
 226                   goto next0;
 227                 }
 228             }
 229           else if (t == 1)
 230             {
 231               if (len != 0)
 232                 break;
 233             }
 234           else if (t == 4)
 235             {
 236               if (len != 2)
 237                 break;
 238
 239               if ((a1 = read_hex_byte (f)) < 0 ||
 240                   (a2 = read_hex_byte (f)) < 0)
 241                 break;
 242
 243               sum += a1 + a2;
 244
 245               hi16 = (a1<<8) + a2;
 246             }
 247           else
 248             break;
 249
 250           if ((b = read_hex_byte (f)) < 0)
 251             break;
 252
 253           sum = -sum;
 254
 255           if (sum != b)
 256             {
 257               printf ("*** HEX file checksum error (expected 0x%02x)\n", sum);
 258               break;
 259             }
 260
 261           c = fgetc (f);
 262
 263           if ((c != '\r') && (c != '\n'))
 264             break;
 265
 266           if (t == 1)
 267             {
 268               result = 1;
 269               break;
 270             }
 271         }
 272
 273       if (result == 0)
 274         printf ("*** HEX file syntax error\n");
 275
 276       fclose (f);
 277     }
 278
 279   return result;
 280 }
 281
 282 #endif
 283
 284 /*---------------------------------------------------------------------------*/
 285
 286 #ifdef ROBOT
 287 // no separate compilation
 288 #include "debug.c"
 289 #include "gc.c"
 290 #include "bignums.c"
 291 #include "primitives.c"
 292 #include "dispatch.c"
 293 #endif
 294
 295 /*---------------------------------------------------------------------------*/
 296
 297 #ifdef WORKSTATION
 298
 299 void usage ()
 300 {
 301   printf ("usage: sim file.hex\n");
 302   exit (1);
 303 }
 304
 305 int main (int argc, char *argv[])
 306 {
 307   int errcode = 0;
 308   rom_addr rom_start_addr = 0;
 309
 310 #ifdef TEST_BIGNUM
 311   test();
 312 #endif
 313
 314   if (argc > 1 && argv[1][0] == '-' && argv[1][1] == 's')
 315     {
 316       int h1;
 317       int h2;
 318       int h3;
 319       int h4;
 320
 321       if ((h1 = hex (argv[1][2])) < 0 ||
 322           (h2 = hex (argv[1][3])) < 0 ||
 323           (h3 = hex (argv[1][4])) != 0 ||
 324           (h4 = hex (argv[1][5])) != 0 ||
 325           argv[1][6] != '\0')
 326         usage ();
 327
 328       rom_start_addr = (h1 << 12) | (h2 << 8) | (h3 << 4) | h4;
 329
 330       argv++;
 331       argc--;
 332     }
 333
 334 #ifdef DEBUG
 335   printf ("Start address = 0x%04x\n", rom_start_addr + CODE_START);
 336 #endif
 337
 338   if (argc != 2)
 339     usage ();
 340
 341   if (!read_hex_file (argv[1]))
 342     printf ("*** Could not read hex file \"%s\"\n", argv[1]);
 343   else
 344     {
 345       int i;
 346
 347       if (rom_get (CODE_START+0) != 0xfb ||
 348           rom_get (CODE_START+1) != 0xd7)
 349         printf ("*** The hex file was not compiled with PICOBIT\n");
 350       else
 351         {
 352 #if 0
 353           for (i=0; i<8192; i++)
 354             if (rom_get (i) != 0xff)
 355               printf ("rom_mem[0x%04x] = 0x%02x\n", i, rom_get (i));
 356 #endif
 357
 358           interpreter ();
 359
 360 #ifdef DEBUG_GC
 361           printf ("**************** memory needed = %d\n", max_live+1);
 362 #endif
 363         }
 364     }
 365
 366   return errcode;
 367 }
 368
 369 #endif
 370
 371 #ifdef SIXPIC
 372 interpreter();
 373 #endif
 374
 375 #ifdef HI_TECH_C
 376 void main () {
 377   interpreter();
 378 }
 379 #endif