| 1 | /* Print GOULD RISC instructions for GDB, the GNU debugger. |
| 2 | Copyright 1986, 1987, 1989, 1991 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "symtab.h" |
| 22 | #include "frame.h" |
| 23 | #include "gdbcore.h" |
| 24 | #if defined GOULD_PN |
| 25 | #include "opcode/pn.h" |
| 26 | #else |
| 27 | #include "opcode/np1.h" |
| 28 | #endif |
| 29 | |
| 30 | /* GOULD RISC instructions are never longer than this many bytes. */ |
| 31 | #define MAXLEN 4 |
| 32 | |
| 33 | /* Number of elements in the opcode table. */ |
| 34 | #define NOPCODES (sizeof gld_opcodes / sizeof gld_opcodes[0]) |
| 35 | |
| 36 | \f |
| 37 | /* Print the GOULD instruction at address MEMADDR in debugged memory, |
| 38 | on STREAM. Returns length of the instruction, in bytes. */ |
| 39 | |
| 40 | int |
| 41 | print_insn (memaddr, stream) |
| 42 | CORE_ADDR memaddr; |
| 43 | FILE *stream; |
| 44 | { |
| 45 | unsigned char buffer[MAXLEN]; |
| 46 | register int i; |
| 47 | register char *d; |
| 48 | register int bestmask; |
| 49 | unsigned best; |
| 50 | int temp, index, bestlen; |
| 51 | |
| 52 | read_memory (memaddr, buffer, MAXLEN); |
| 53 | |
| 54 | bestmask = 0; |
| 55 | index = -1; |
| 56 | best = 0xffffffff; |
| 57 | for (i = 0; i < NOPCODES; i++) |
| 58 | { |
| 59 | register unsigned int opcode = gld_opcodes[i].opcode; |
| 60 | register unsigned int mask = gld_opcodes[i].mask; |
| 61 | register unsigned int len = gld_opcodes[i].length; |
| 62 | register unsigned int test; |
| 63 | |
| 64 | /* Get possible opcode bytes into integer */ |
| 65 | test = buffer[0] << 24; |
| 66 | test |= buffer[1] << 16; |
| 67 | test |= buffer[2] << 8; |
| 68 | test |= buffer[3]; |
| 69 | |
| 70 | /* Mask with opcode and see if match */ |
| 71 | if ((opcode & mask) == (test & mask)) |
| 72 | { |
| 73 | /* See if second or third match */ |
| 74 | if (index >= 0) |
| 75 | { |
| 76 | /* Take new one if it looks good */ |
| 77 | if (bestlen == MAXLEN && len == MAXLEN) |
| 78 | { |
| 79 | /* See if lower bits matched */ |
| 80 | if (((bestmask & 3) == 0) && |
| 81 | ((mask & 3) != 0)) |
| 82 | { |
| 83 | bestmask = mask; |
| 84 | bestlen = len; |
| 85 | best = test; |
| 86 | index = i; |
| 87 | } |
| 88 | } |
| 89 | } |
| 90 | else |
| 91 | { |
| 92 | /* First match, save it */ |
| 93 | bestmask = mask; |
| 94 | bestlen = len; |
| 95 | best = test; |
| 96 | index = i; |
| 97 | } |
| 98 | } |
| 99 | } |
| 100 | |
| 101 | /* Handle undefined instructions. */ |
| 102 | if (index < 0) |
| 103 | { |
| 104 | fprintf (stream, "undefined 0%o",(buffer[0]<<8)+buffer[1]); |
| 105 | return 2; |
| 106 | } |
| 107 | |
| 108 | /* Print instruction name */ |
| 109 | fprintf (stream, "%-12s", gld_opcodes[index].name); |
| 110 | |
| 111 | /* Adjust if short instruction */ |
| 112 | if (gld_opcodes[index].length < 4) |
| 113 | { |
| 114 | best >>= 16; |
| 115 | i = 0; |
| 116 | } |
| 117 | else |
| 118 | { |
| 119 | i = 16; |
| 120 | } |
| 121 | |
| 122 | /* Dump out instruction arguments */ |
| 123 | for (d = gld_opcodes[index].args; *d; ++d) |
| 124 | { |
| 125 | switch (*d) |
| 126 | { |
| 127 | case 'f': |
| 128 | fprintf (stream, "%d", (best >> (7 + i)) & 7); |
| 129 | break; |
| 130 | case 'r': |
| 131 | fprintf (stream, "r%d", (best >> (7 + i)) & 7); |
| 132 | break; |
| 133 | case 'R': |
| 134 | fprintf (stream, "r%d", (best >> (4 + i)) & 7); |
| 135 | break; |
| 136 | case 'b': |
| 137 | fprintf (stream, "b%d", (best >> (7 + i)) & 7); |
| 138 | break; |
| 139 | case 'B': |
| 140 | fprintf (stream, "b%d", (best >> (4 + i)) & 7); |
| 141 | break; |
| 142 | case 'v': |
| 143 | fprintf (stream, "b%d", (best >> (7 + i)) & 7); |
| 144 | break; |
| 145 | case 'V': |
| 146 | fprintf (stream, "b%d", (best >> (4 + i)) & 7); |
| 147 | break; |
| 148 | case 'X': |
| 149 | temp = (best >> 20) & 7; |
| 150 | if (temp) |
| 151 | fprintf (stream, "r%d", temp); |
| 152 | else |
| 153 | putc ('0', stream); |
| 154 | break; |
| 155 | case 'A': |
| 156 | temp = (best >> 16) & 7; |
| 157 | if (temp) |
| 158 | fprintf (stream, "(b%d)", temp); |
| 159 | break; |
| 160 | case 'S': |
| 161 | fprintf (stream, "#%d", best & 0x1f); |
| 162 | break; |
| 163 | case 'I': |
| 164 | fprintf (stream, "#%x", best & 0xffff); |
| 165 | break; |
| 166 | case 'O': |
| 167 | fprintf (stream, "%x", best & 0xffff); |
| 168 | break; |
| 169 | case 'h': |
| 170 | fprintf (stream, "%d", best & 0xfffe); |
| 171 | break; |
| 172 | case 'd': |
| 173 | fprintf (stream, "%d", best & 0xfffc); |
| 174 | break; |
| 175 | case 'T': |
| 176 | fprintf (stream, "%d", (best >> 8) & 0xff); |
| 177 | break; |
| 178 | case 'N': |
| 179 | fprintf (stream, "%d", best & 0xff); |
| 180 | break; |
| 181 | default: |
| 182 | putc (*d, stream); |
| 183 | break; |
| 184 | } |
| 185 | } |
| 186 | |
| 187 | /* Return length of instruction */ |
| 188 | return (gld_opcodes[index].length); |
| 189 | } |
| 190 | |
| 191 | /* |
| 192 | * Find the number of arguments to a function. |
| 193 | */ |
| 194 | findarg(frame) |
| 195 | struct frame_info *frame; |
| 196 | { |
| 197 | register struct symbol *func; |
| 198 | register unsigned pc; |
| 199 | |
| 200 | #ifdef notdef |
| 201 | /* find starting address of frame function */ |
| 202 | pc = get_pc_function_start (frame->pc); |
| 203 | |
| 204 | /* find function symbol info */ |
| 205 | func = find_pc_function (pc); |
| 206 | |
| 207 | /* call blockframe code to look for match */ |
| 208 | if (func != NULL) |
| 209 | return (func->value.block->nsyms / sizeof(int)); |
| 210 | #endif |
| 211 | |
| 212 | return (-1); |
| 213 | } |
| 214 | |
| 215 | /* |
| 216 | * In the case of the NPL, the frame's norminal address is Br2 and the |
| 217 | * previous routines frame is up the stack X bytes. Finding out what |
| 218 | * 'X' is can be tricky. |
| 219 | * |
| 220 | * 1.) stored in the code function header xA(Br1). |
| 221 | * 2.) must be careful of recurssion. |
| 222 | */ |
| 223 | FRAME_ADDR |
| 224 | findframe(thisframe) |
| 225 | FRAME thisframe; |
| 226 | { |
| 227 | register FRAME_ADDR pointer; |
| 228 | FRAME_ADDR framechain(); |
| 229 | #if 0 |
| 230 | struct frame_info *frame; |
| 231 | |
| 232 | /* Setup toplevel frame structure */ |
| 233 | frame->pc = read_pc(); |
| 234 | frame->next_frame = 0; |
| 235 | frame->frame = read_register (SP_REGNUM); /* Br2 */ |
| 236 | |
| 237 | /* Search for this frame (start at current Br2) */ |
| 238 | do |
| 239 | { |
| 240 | pointer = framechain(frame); |
| 241 | frame->next_frame = frame->frame; |
| 242 | frame->frame = pointer; |
| 243 | frame->pc = FRAME_SAVED_PC(frame); |
| 244 | } |
| 245 | while (frame->next_frame != thisframe); |
| 246 | #endif |
| 247 | |
| 248 | pointer = framechain (thisframe); |
| 249 | |
| 250 | /* stop gap for now, end at __base3 */ |
| 251 | if (thisframe->pc == 0) |
| 252 | return 0; |
| 253 | |
| 254 | return pointer; |
| 255 | } |
| 256 | |
| 257 | /* |
| 258 | * Gdb front-end and internal framechain routine. |
| 259 | * Go back up stack one level. Tricky... |
| 260 | */ |
| 261 | FRAME_ADDR |
| 262 | framechain(frame) |
| 263 | register struct frame_info *frame; |
| 264 | { |
| 265 | register CORE_ADDR func, prevsp; |
| 266 | register unsigned value; |
| 267 | |
| 268 | /* Get real function start address from internal frame address */ |
| 269 | func = get_pc_function_start(frame->pc); |
| 270 | |
| 271 | /* If no stack given, read register Br1 "(sp)" */ |
| 272 | if (!frame->frame) |
| 273 | prevsp = read_register (SP_REGNUM); |
| 274 | else |
| 275 | prevsp = frame->frame; |
| 276 | |
| 277 | /* Check function header, case #2 */ |
| 278 | value = read_memory_integer (func, 4); |
| 279 | if (value) |
| 280 | { |
| 281 | /* 32bit call push value stored in function header */ |
| 282 | prevsp += value; |
| 283 | } |
| 284 | else |
| 285 | { |
| 286 | /* read half-word from suabr at start of function */ |
| 287 | prevsp += read_memory_integer (func + 10, 2); |
| 288 | } |
| 289 | |
| 290 | return (prevsp); |
| 291 | } |