| 1 | /* Print VAX instructions for GDB, the GNU debugger. |
| 2 | Copyright 1986, 1989, 1991, 1992, 1996 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 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, |
| 19 | Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | #include "defs.h" |
| 22 | #include "symtab.h" |
| 23 | #include "opcode/vax.h" |
| 24 | #include "gdbcore.h" |
| 25 | #include "frame.h" |
| 26 | #include "value.h" |
| 27 | |
| 28 | /* Vax instructions are never longer than this. */ |
| 29 | #define MAXLEN 62 |
| 30 | |
| 31 | /* Number of elements in the opcode table. */ |
| 32 | #define NOPCODES (sizeof votstrs / sizeof votstrs[0]) |
| 33 | |
| 34 | static unsigned char *print_insn_arg (); |
| 35 | \f |
| 36 | /* Advance PC across any function entry prologue instructions |
| 37 | to reach some "real" code. */ |
| 38 | |
| 39 | CORE_ADDR |
| 40 | vax_skip_prologue (CORE_ADDR pc) |
| 41 | { |
| 42 | register int op = (unsigned char) read_memory_integer (pc, 1); |
| 43 | if (op == 0x11) |
| 44 | pc += 2; /* skip brb */ |
| 45 | if (op == 0x31) |
| 46 | pc += 3; /* skip brw */ |
| 47 | if (op == 0xC2 |
| 48 | && ((unsigned char) read_memory_integer (pc + 2, 1)) == 0x5E) |
| 49 | pc += 3; /* skip subl2 */ |
| 50 | if (op == 0x9E |
| 51 | && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xAE |
| 52 | && ((unsigned char) read_memory_integer (pc + 3, 1)) == 0x5E) |
| 53 | pc += 4; /* skip movab */ |
| 54 | if (op == 0x9E |
| 55 | && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xCE |
| 56 | && ((unsigned char) read_memory_integer (pc + 4, 1)) == 0x5E) |
| 57 | pc += 5; /* skip movab */ |
| 58 | if (op == 0x9E |
| 59 | && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xEE |
| 60 | && ((unsigned char) read_memory_integer (pc + 6, 1)) == 0x5E) |
| 61 | pc += 7; /* skip movab */ |
| 62 | return pc; |
| 63 | } |
| 64 | |
| 65 | /* Return number of args passed to a frame. |
| 66 | Can return -1, meaning no way to tell. */ |
| 67 | |
| 68 | int |
| 69 | vax_frame_num_args (struct frame_info *fi) |
| 70 | { |
| 71 | return (0xff & read_memory_integer (FRAME_ARGS_ADDRESS (fi), 1)); |
| 72 | } |
| 73 | |
| 74 | |
| 75 | |
| 76 | /* Print the vax instruction at address MEMADDR in debugged memory, |
| 77 | from disassembler info INFO. |
| 78 | Returns length of the instruction, in bytes. */ |
| 79 | |
| 80 | static int |
| 81 | vax_print_insn (CORE_ADDR memaddr, disassemble_info *info) |
| 82 | { |
| 83 | unsigned char buffer[MAXLEN]; |
| 84 | register int i; |
| 85 | register unsigned char *p; |
| 86 | const char *d; |
| 87 | |
| 88 | int status = (*info->read_memory_func) (memaddr, buffer, MAXLEN, info); |
| 89 | if (status != 0) |
| 90 | { |
| 91 | (*info->memory_error_func) (status, memaddr, info); |
| 92 | return -1; |
| 93 | } |
| 94 | |
| 95 | for (i = 0; i < NOPCODES; i++) |
| 96 | if (votstrs[i].detail.code == buffer[0] |
| 97 | || votstrs[i].detail.code == *(unsigned short *) buffer) |
| 98 | break; |
| 99 | |
| 100 | /* Handle undefined instructions. */ |
| 101 | if (i == NOPCODES) |
| 102 | { |
| 103 | (*info->fprintf_func) (info->stream, "0%o", buffer[0]); |
| 104 | return 1; |
| 105 | } |
| 106 | |
| 107 | (*info->fprintf_func) (info->stream, "%s", votstrs[i].name); |
| 108 | |
| 109 | /* Point at first byte of argument data, |
| 110 | and at descriptor for first argument. */ |
| 111 | p = buffer + 1 + (votstrs[i].detail.code >= 0x100); |
| 112 | d = votstrs[i].detail.args; |
| 113 | |
| 114 | if (*d) |
| 115 | (*info->fprintf_func) (info->stream, " "); |
| 116 | |
| 117 | while (*d) |
| 118 | { |
| 119 | p = print_insn_arg (d, p, memaddr + (p - buffer), info); |
| 120 | d += 2; |
| 121 | if (*d) |
| 122 | (*info->fprintf_func) (info->stream, ","); |
| 123 | } |
| 124 | return p - buffer; |
| 125 | } |
| 126 | |
| 127 | static unsigned char * |
| 128 | print_insn_arg (char *d, register char *p, CORE_ADDR addr, |
| 129 | disassemble_info *info) |
| 130 | { |
| 131 | register int regnum = *p & 0xf; |
| 132 | float floatlitbuf; |
| 133 | |
| 134 | if (*d == 'b') |
| 135 | { |
| 136 | if (d[1] == 'b') |
| 137 | (*info->fprintf_func) (info->stream, "0x%x", addr + *p++ + 1); |
| 138 | else |
| 139 | { |
| 140 | (*info->fprintf_func) (info->stream, "0x%x", addr + *(short *) p + 2); |
| 141 | p += 2; |
| 142 | } |
| 143 | } |
| 144 | else |
| 145 | switch ((*p++ >> 4) & 0xf) |
| 146 | { |
| 147 | case 0: |
| 148 | case 1: |
| 149 | case 2: |
| 150 | case 3: /* Literal mode */ |
| 151 | if (d[1] == 'd' || d[1] == 'f' || d[1] == 'g' || d[1] == 'h') |
| 152 | { |
| 153 | *(int *) &floatlitbuf = 0x4000 + ((p[-1] & 0x3f) << 4); |
| 154 | (*info->fprintf_func) (info->stream, "$%f", floatlitbuf); |
| 155 | } |
| 156 | else |
| 157 | (*info->fprintf_func) (info->stream, "$%d", p[-1] & 0x3f); |
| 158 | break; |
| 159 | |
| 160 | case 4: /* Indexed */ |
| 161 | p = (char *) print_insn_arg (d, p, addr + 1, info); |
| 162 | (*info->fprintf_func) (info->stream, "[%s]", REGISTER_NAME (regnum)); |
| 163 | break; |
| 164 | |
| 165 | case 5: /* Register */ |
| 166 | (*info->fprintf_func) (info->stream, REGISTER_NAME (regnum)); |
| 167 | break; |
| 168 | |
| 169 | case 7: /* Autodecrement */ |
| 170 | (*info->fprintf_func) (info->stream, "-"); |
| 171 | case 6: /* Register deferred */ |
| 172 | (*info->fprintf_func) (info->stream, "(%s)", REGISTER_NAME (regnum)); |
| 173 | break; |
| 174 | |
| 175 | case 9: /* Autoincrement deferred */ |
| 176 | (*info->fprintf_func) (info->stream, "@"); |
| 177 | if (regnum == PC_REGNUM) |
| 178 | { |
| 179 | (*info->fprintf_func) (info->stream, "#"); |
| 180 | info->target = *(long *) p; |
| 181 | (*info->print_address_func) (info->target, info); |
| 182 | p += 4; |
| 183 | break; |
| 184 | } |
| 185 | case 8: /* Autoincrement */ |
| 186 | if (regnum == PC_REGNUM) |
| 187 | { |
| 188 | (*info->fprintf_func) (info->stream, "#"); |
| 189 | switch (d[1]) |
| 190 | { |
| 191 | case 'b': |
| 192 | (*info->fprintf_func) (info->stream, "%d", *p++); |
| 193 | break; |
| 194 | |
| 195 | case 'w': |
| 196 | (*info->fprintf_func) (info->stream, "%d", *(short *) p); |
| 197 | p += 2; |
| 198 | break; |
| 199 | |
| 200 | case 'l': |
| 201 | (*info->fprintf_func) (info->stream, "%d", *(long *) p); |
| 202 | p += 4; |
| 203 | break; |
| 204 | |
| 205 | case 'q': |
| 206 | (*info->fprintf_func) (info->stream, "0x%x%08x", |
| 207 | ((long *) p)[1], ((long *) p)[0]); |
| 208 | p += 8; |
| 209 | break; |
| 210 | |
| 211 | case 'o': |
| 212 | (*info->fprintf_func) (info->stream, "0x%x%08x%08x%08x", |
| 213 | ((long *) p)[3], ((long *) p)[2], |
| 214 | ((long *) p)[1], ((long *) p)[0]); |
| 215 | p += 16; |
| 216 | break; |
| 217 | |
| 218 | case 'f': |
| 219 | if (INVALID_FLOAT (p, 4)) |
| 220 | (*info->fprintf_func) (info->stream, |
| 221 | "<<invalid float 0x%x>>", |
| 222 | *(int *) p); |
| 223 | else |
| 224 | (*info->fprintf_func) (info->stream, "%f", *(float *) p); |
| 225 | p += 4; |
| 226 | break; |
| 227 | |
| 228 | case 'd': |
| 229 | if (INVALID_FLOAT (p, 8)) |
| 230 | (*info->fprintf_func) (info->stream, |
| 231 | "<<invalid float 0x%x%08x>>", |
| 232 | ((long *) p)[1], ((long *) p)[0]); |
| 233 | else |
| 234 | (*info->fprintf_func) (info->stream, "%f", *(double *) p); |
| 235 | p += 8; |
| 236 | break; |
| 237 | |
| 238 | case 'g': |
| 239 | (*info->fprintf_func) (info->stream, "g-float"); |
| 240 | p += 8; |
| 241 | break; |
| 242 | |
| 243 | case 'h': |
| 244 | (*info->fprintf_func) (info->stream, "h-float"); |
| 245 | p += 16; |
| 246 | break; |
| 247 | |
| 248 | } |
| 249 | } |
| 250 | else |
| 251 | (*info->fprintf_func) (info->stream, "(%s)+", REGISTER_NAME (regnum)); |
| 252 | break; |
| 253 | |
| 254 | case 11: /* Byte displacement deferred */ |
| 255 | (*info->fprintf_func) (info->stream, "@"); |
| 256 | case 10: /* Byte displacement */ |
| 257 | if (regnum == PC_REGNUM) |
| 258 | { |
| 259 | info->target = addr + *p + 2; |
| 260 | (*info->print_address_func) (info->target, info); |
| 261 | } |
| 262 | else |
| 263 | (*info->fprintf_func) (info->stream, "%d(%s)", *p, REGISTER_NAME (regnum)); |
| 264 | p += 1; |
| 265 | break; |
| 266 | |
| 267 | case 13: /* Word displacement deferred */ |
| 268 | (*info->fprintf_func) (info->stream, "@"); |
| 269 | case 12: /* Word displacement */ |
| 270 | if (regnum == PC_REGNUM) |
| 271 | { |
| 272 | info->target = addr + *(short *) p + 3; |
| 273 | (*info->print_address_func) (info->target, info); |
| 274 | } |
| 275 | else |
| 276 | (*info->fprintf_func) (info->stream, "%d(%s)", |
| 277 | *(short *) p, REGISTER_NAME (regnum)); |
| 278 | p += 2; |
| 279 | break; |
| 280 | |
| 281 | case 15: /* Long displacement deferred */ |
| 282 | (*info->fprintf_func) (info->stream, "@"); |
| 283 | case 14: /* Long displacement */ |
| 284 | if (regnum == PC_REGNUM) |
| 285 | { |
| 286 | info->target = addr + *(short *) p + 5; |
| 287 | (*info->print_address_func) (info->target, info); |
| 288 | } |
| 289 | else |
| 290 | (*info->fprintf_func) (info->stream, "%d(%s)", |
| 291 | *(long *) p, REGISTER_NAME (regnum)); |
| 292 | p += 4; |
| 293 | } |
| 294 | |
| 295 | return (unsigned char *) p; |
| 296 | } |
| 297 | |
| 298 | void |
| 299 | _initialize_vax_tdep (void) |
| 300 | { |
| 301 | tm_print_insn = vax_print_insn; |
| 302 | } |