gdb/m88k-pinsn.c

   1 /* This file has been modified by Data General Corporation, November 1989. */
   2
   3 #include <stdio.h>
   4 #include "m88k-opcode.h"
   5 #include "defs.h"
   6 #include "symtab.h"
   7
   8 void sprint_address ();
   9
  10 /* Changed hashtab to hashtable to avoid naming conflict
  11    with libdc.o (used for tdesc) for m88k.
  12 */
  13
  14 INSTAB  *hashtable[HASHVAL] = {0};
  15
  16 /*
  17 *               Disassemble an M88000 Instruction
  18 *
  19 *
  20 *       This module decodes the first instruction in inbuf.  It uses the pc
  21 *       to display pc-relative displacements.  It writes the disassembled
  22 *       instruction in outbuf.
  23 *
  24 *                       Revision History
  25 *
  26 *       Revision 1.0    11/08/85        Creation date by Motorola
  27 *                       05/11/89        R. Trawick adapted to GDB interface.
  28 */
  29 #define MAXLEN 20
  30
  31 print_insn (memaddr, stream)
  32      CORE_ADDR memaddr;
  33      FILE *stream;
  34 {
  35   unsigned char buffer[MAXLEN];
  36   /* should be expanded if disassembler prints symbol names */
  37   char outbuf[100];
  38   int n;
  39
  40   /* Instruction addresses may have low two bits set. Clear them.       */
  41   memaddr&= 0xfffffffc;
  42   read_memory (memaddr, buffer, MAXLEN);
  43
  44   n = m88kdis ((int)memaddr, buffer, outbuf);
  45
  46   fputs (outbuf, stream);
  47
  48   return (n);
  49 }
  50
  51 /*
  52  * disassemble the first instruction in 'inbuf'.
  53  * 'pc' should be the address of this instruction, it will
  54  *   be used to print the target address if this is a relative jump or call
  55  * 'outbuf' gets filled in with the disassembled instruction.  It should
  56  *   be long enough to hold the longest disassembled instruction.
  57  *   100 bytes is certainly enough, unless symbol printing is added later
  58  * The function returns the length of this instruction in bytes.
  59  */
  60
  61 int m88kdis( pc, inbuf, outbuf )
  62
  63     int         pc;
  64     int         *inbuf;
  65     char        *outbuf;
  66
  67 {   static              ihashtab_initialized = 0;
  68     int                 instruction;
  69     unsigned int        opcode;
  70     INSTAB              *entry_ptr;
  71     int                 opmask;
  72     int                 class;
  73
  74     instruction= *inbuf;
  75
  76     if (!ihashtab_initialized) {
  77         init_disasm();
  78     }
  79
  80     /* create a the appropriate mask to isolate the opcode */
  81     opmask= DEFMASK;
  82     class= instruction & DEFMASK;
  83     if ((class >= SFU0) && (class <= SFU7)) {
  84         if (instruction < SFU1) {
  85             opmask= CTRLMASK;
  86         } else {
  87             opmask= SFUMASK;
  88         }
  89     } else if (class == RRR) {
  90         opmask= RRRMASK;
  91     } else if (class == RRI10) {
  92         opmask= RRI10MASK;
  93     }
  94
  95     /* isolate the opcode */
  96     opcode= instruction & opmask;
  97
  98     /* search the hash table with the isolated opcode */
  99     for (entry_ptr= hashtable[ opcode % HASHVAL ];
 100          (entry_ptr != NULL) && (entry_ptr->opcode != opcode);
 101          entry_ptr= entry_ptr->next) {
 102     }
 103
 104     if (entry_ptr == NULL) {
 105         sprintf( outbuf, "word\t%08x", instruction );
 106     } else {
 107         sprintf( outbuf, "%s\t", entry_ptr->mnemonic );
 108         sprintop( &outbuf[strlen(outbuf)], &(entry_ptr->op1), instruction, pc, 1 );
 109         sprintop( &outbuf[strlen(outbuf)], &(entry_ptr->op2), instruction, pc, 0 );
 110         sprintop( &outbuf[strlen(outbuf)], &(entry_ptr->op3), instruction, pc, 0 );
 111     }
 112
 113
 114     return 4;
 115 }
 116 \f
 117
 118 /*
 119 *                      Decode an Operand of an Instruction
 120 *
 121 *                       Functional Description
 122 *
 123 *       This module formats and writes an operand of an instruction to buf
 124 *       based on the operand specification.  When the first flag is set this
 125 *       is the first operand of an instruction.  Undefined operand types
 126 *       cause a <dis error> message.
 127 *
 128 *                       Parameters
 129 *       char    *buf            buffer where the operand may be printed
 130 *       OPSPEC  *opptr          Pointer to an operand specification
 131 *       UINT    inst            Instruction from which operand is extracted
 132 *       UINT    pc              PC of instruction; used for pc-relative disp.
 133 *       int     first           Flag which if nonzero indicates the first
 134 *                               operand of an instruction
 135 *
 136 *                       Output
 137 *
 138 *       The operand specified is extracted from the instruction and is
 139 *       written to buf in the format specified. The operand is preceded
 140 *       by a comma if it is not the first operand of an instruction and it
 141 *       is not a register indirect form.  Registers are preceded by 'r' and
 142 *       hex values by '0x'.
 143 *
 144 *                       Revision History
 145 *
 146 *       Revision 1.0    11/08/85        Creation date
 147 */
 148
 149 sprintop( buf, opptr, inst, pc, first )
 150
 151    char   *buf;
 152    OPSPEC *opptr;
 153    UINT   inst;
 154    int    pc;
 155    int    first;
 156
 157 {  int    extracted_field;
 158    char   *cond_mask_sym;
 159    char   cond_mask_sym_buf[6];
 160
 161    if (opptr->width == 0)
 162       return;
 163
 164    switch(opptr->type) {
 165       case CRREG:
 166                        if (!first)
 167                            *buf++= ',';
 168                        sprintf( buf, "cr%d", UEXT(inst,opptr->offset,opptr->width));
 169                        break;
 170
 171       case FCRREG:
 172                        if (!first)
 173                            *buf++= ',';
 174                        sprintf( buf, "fcr%d", UEXT(inst,opptr->offset,opptr->width));
 175                        break;
 176
 177       case REGSC:
 178                        sprintf( buf, "[r%d]", UEXT(inst,opptr->offset,opptr->width));
 179                        break;
 180
 181       case REG:
 182                        if (!first)
 183                            *buf++= ',';
 184                        sprintf( buf, "r%d", UEXT(inst,opptr->offset,opptr->width));
 185                        break;
 186
 187       case HEX:
 188                         if (!first)
 189                            *buf++= ',';
 190                         extracted_field= UEXT(inst, opptr->offset, opptr->width);
 191                         if (extracted_field == 0) {
 192                             sprintf( buf, "0" );
 193                         } else {
 194                             sprintf( buf, "0x%02x", extracted_field );
 195                         }
 196                         break;
 197
 198       case CONDMASK:
 199                         if (!first)
 200                            *buf++= ',';
 201                         extracted_field= UEXT(inst, opptr->offset, opptr->width);
 202                         switch (extracted_field & 0x0f) {
 203                           case 0x1:     cond_mask_sym= "gt0";
 204                                         break;
 205                           case 0x2:     cond_mask_sym= "eq0";
 206                                         break;
 207                           case 0x3:     cond_mask_sym= "ge0";
 208                                         break;
 209                           case 0xc:     cond_mask_sym= "lt0";
 210                                         break;
 211                           case 0xd:     cond_mask_sym= "ne0";
 212                                         break;
 213                           case 0xe:     cond_mask_sym= "le0";
 214                                         break;
 215                           default:      cond_mask_sym= cond_mask_sym_buf;
 216                                         sprintf( cond_mask_sym_buf,
 217                                                  "%x",
 218                                                  extracted_field );
 219                                         break;
 220                         }
 221                         strcpy( buf, cond_mask_sym );
 222                         break;
 223
 224       case PCREL:
 225                         if (!first)
 226                            *buf++= ',';
 227                         sprint_address( pc + 4*(SEXT(inst,opptr->offset,opptr->width)),
 228                                         buf );
 229                         break;
 230
 231       case CONT:
 232                        sprintf( buf,
 233                                 "%d,r%d",
 234                                 UEXT(inst,opptr->offset,5),
 235                                 UEXT(inst,(opptr->offset)+5,5) );
 236                        break;
 237
 238       case BF:
 239                        if (!first)
 240                            *buf++= ',';
 241                        sprintf( buf,
 242                                 "%d<%d>",
 243                                 UEXT(inst,(opptr->offset)+5,5),
 244                                 UEXT(inst,opptr->offset,5));
 245                        break;
 246
 247       default:
 248                        sprintf( buf, "<dis error: %08x>", inst );
 249     }
 250
 251 }
 252
 253 /*
 254 *                 Initialize the Disassembler Instruction Table
 255 *
 256 *       Initialize the hash table and instruction table for the disassembler.
 257 *       This should be called once before the first call to disasm().
 258 *
 259 *                       Parameters
 260 *
 261 *                       Output
 262 *
 263 *       If the debug option is selected, certain statistics about the hashing
 264 *       distribution are written to stdout.
 265 *
 266 *                       Revision History
 267 *
 268 *       Revision 1.0    11/08/85        Creation date
 269 */
 270
 271 init_disasm()
 272 {
 273    int i,size;
 274
 275    for (i=0 ; i < HASHVAL ; i++)
 276       hashtable[i] = NULL;
 277
 278    for (i=0, size =  sizeof(instructions) / sizeof(INSTAB) ; i < size ;
 279        install(&instructions[i++]));
 280
 281 }
 282
 283 /*
 284 *       Insert an instruction into the disassembler table by hashing the
 285 *       opcode and inserting it into the linked list for that hash value.
 286 *
 287 *                       Parameters
 288 *
 289 *       INSTAB *instptr         Pointer to the entry in the instruction table
 290 *                               to be installed
 291 *
 292 *       Revision 1.0    11/08/85        Creation date
 293 *                       05/11/89        R. TRAWICK ADAPTED FROM MOTOROLA
 294 */
 295
 296 install(instptr)
 297    INSTAB *instptr;
 298 {
 299    UINT i;
 300
 301    i = (instptr->opcode) % HASHVAL;
 302    instptr->next = hashtable[i];
 303    hashtable[i] = instptr;
 304 }
 305 \f
 306
 307 /* adapted from print_address in printcmd by R. Trawick 5/15/89.  The two should
 308    be combined.
 309  */
 310
 311 void sprint_address (addr, buffer)
 312
 313      CORE_ADDR  addr;
 314      char       *buffer;
 315
 316 {
 317         register int    i;
 318         struct symbol   *fs;
 319         char            *name;
 320         int             name_location;
 321
 322         sprintf ( buffer, "0x%x", addr);
 323
 324         fs = find_pc_function (addr);
 325
 326         if (!fs) {
 327             i = find_pc_misc_function (addr);
 328
 329             if (i < 0) return;  /* If nothing comes through, don't
 330                                    print anything symbolic */
 331
 332             name = misc_function_vector[i].name;
 333             name_location = misc_function_vector[i].address;
 334         } else {
 335             name = fs->name;
 336             name_location = BLOCK_START (SYMBOL_BLOCK_VALUE (fs));
 337         }
 338
 339         if (addr - name_location)
 340             sprintf (buffer, " <%s+%d>", name, addr - name_location);
 341         else
 342             sprintf (buffer, " <%s>", name);
 343 }