| 1 | /* Generic stabs parsing for gas. |
| 2 | Copyright (C) 1989, 1990, 1991, 1993 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GAS, the GNU Assembler. |
| 5 | |
| 6 | GAS is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as |
| 8 | published by the Free Software Foundation; either version 2, |
| 9 | or (at your option) any later version. |
| 10 | |
| 11 | GAS is distributed in the hope that it will be useful, but |
| 12 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 14 | the GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public |
| 17 | License along with GAS; see the file COPYING. If not, write |
| 18 | to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 19 | |
| 20 | #include "as.h" |
| 21 | #include "libiberty.h" |
| 22 | #include "obstack.h" |
| 23 | #include "subsegs.h" |
| 24 | |
| 25 | /* We need this, despite the apparent object format dependency, since |
| 26 | it defines stab types, which all object formats can use now. */ |
| 27 | |
| 28 | #include "aout/stab_gnu.h" |
| 29 | |
| 30 | /* Allow backends to override the names used for the stab sections. */ |
| 31 | #ifndef STAB_SECTION_NAME |
| 32 | #define STAB_SECTION_NAME ".stab" |
| 33 | #endif |
| 34 | |
| 35 | #ifndef STAB_STRING_SECTION_NAME |
| 36 | #define STAB_STRING_SECTION_NAME ".stabstr" |
| 37 | #endif |
| 38 | |
| 39 | /* |
| 40 | * Handle .stabX directives, which used to be open-coded. |
| 41 | * So much creeping featurism overloaded the semantics that we decided |
| 42 | * to put all .stabX thinking in one place. Here. |
| 43 | * |
| 44 | * We try to make any .stabX directive legal. Other people's AS will often |
| 45 | * do assembly-time consistency checks: eg assigning meaning to n_type bits |
| 46 | * and "protecting" you from setting them to certain values. (They also zero |
| 47 | * certain bits before emitting symbols. Tut tut.) |
| 48 | * |
| 49 | * If an expression is not absolute we either gripe or use the relocation |
| 50 | * information. Other people's assemblers silently forget information they |
| 51 | * don't need and invent information they need that you didn't supply. |
| 52 | */ |
| 53 | |
| 54 | /* |
| 55 | * Build a string dictionary entry for a .stabX symbol. |
| 56 | * The symbol is added to the .<secname>str section. |
| 57 | */ |
| 58 | |
| 59 | #ifndef SEPARATE_STAB_SECTIONS |
| 60 | #define SEPARATE_STAB_SECTIONS 0 |
| 61 | #endif |
| 62 | |
| 63 | unsigned int |
| 64 | get_stab_string_offset (string, stabstr_secname) |
| 65 | const char *string; |
| 66 | const char *stabstr_secname; |
| 67 | { |
| 68 | unsigned int length; |
| 69 | unsigned int retval; |
| 70 | |
| 71 | if (! SEPARATE_STAB_SECTIONS) |
| 72 | abort (); |
| 73 | |
| 74 | retval = 0; |
| 75 | length = strlen (string); |
| 76 | if (length > 0) |
| 77 | { /* Ordinary case. */ |
| 78 | segT save_seg; |
| 79 | subsegT save_subseg; |
| 80 | segT seg; |
| 81 | char *p; |
| 82 | |
| 83 | save_seg = now_seg; |
| 84 | save_subseg = now_subseg; |
| 85 | |
| 86 | /* Create the stab string section. */ |
| 87 | seg = subseg_new (stabstr_secname, 0); |
| 88 | |
| 89 | retval = seg_info (seg)->stabu.stab_string_size; |
| 90 | if (retval <= 0) |
| 91 | { |
| 92 | /* Make sure the first string is empty. */ |
| 93 | p = frag_more (1); |
| 94 | *p = 0; |
| 95 | retval = seg_info (seg)->stabu.stab_string_size = 1; |
| 96 | #ifdef BFD_ASSEMBLER |
| 97 | bfd_set_section_flags (stdoutput, seg, SEC_READONLY | SEC_DEBUGGING); |
| 98 | if (seg->name == stabstr_secname) |
| 99 | seg->name = xstrdup (stabstr_secname); |
| 100 | #endif |
| 101 | } |
| 102 | |
| 103 | p = frag_more (length + 1); |
| 104 | strcpy (p, string); |
| 105 | |
| 106 | seg_info (seg)->stabu.stab_string_size += length + 1; |
| 107 | |
| 108 | subseg_set (save_seg, save_subseg); |
| 109 | } |
| 110 | |
| 111 | return retval; |
| 112 | } |
| 113 | |
| 114 | #ifdef AOUT_STABS |
| 115 | #ifndef OBJ_PROCESS_STAB |
| 116 | #define OBJ_PROCESS_STAB(SEG,W,S,T,O,D) aout_process_stab(W,S,T,O,D) |
| 117 | #endif |
| 118 | |
| 119 | static void |
| 120 | aout_process_stab (what, string, type, other, desc) |
| 121 | int what; |
| 122 | const char *string; |
| 123 | int type, other, desc; |
| 124 | { |
| 125 | /* Put the stab information in the symbol table. */ |
| 126 | symbolS *symbol; |
| 127 | |
| 128 | /* Create the symbol now, but only insert it into the symbol chain |
| 129 | after any symbols mentioned in the value expression get into the |
| 130 | symbol chain. This is to avoid "continuation symbols" (where one |
| 131 | ends in "\" and the debug info is continued in the next .stabs |
| 132 | directive) from being separated by other random symbols. */ |
| 133 | symbol = symbol_create (string, undefined_section, 0, |
| 134 | (struct frag *) NULL); |
| 135 | if (what == 's' || what == 'n') |
| 136 | { |
| 137 | /* Pick up the value from the input line. */ |
| 138 | symbol->sy_frag = &zero_address_frag; |
| 139 | pseudo_set (symbol); |
| 140 | } |
| 141 | else |
| 142 | { |
| 143 | /* .stabd sets the name to NULL. Why? */ |
| 144 | S_SET_NAME (symbol, NULL); |
| 145 | symbol->sy_frag = frag_now; |
| 146 | S_SET_VALUE (symbol, (valueT) frag_now_fix ()); |
| 147 | } |
| 148 | |
| 149 | symbol_append (symbol, symbol_lastP, &symbol_rootP, &symbol_lastP); |
| 150 | |
| 151 | S_SET_TYPE (symbol, type); |
| 152 | S_SET_OTHER (symbol, other); |
| 153 | S_SET_DESC (symbol, desc); |
| 154 | } |
| 155 | #endif |
| 156 | |
| 157 | /* This can handle different kinds of stabs (s,n,d) and different |
| 158 | kinds of stab sections. */ |
| 159 | |
| 160 | static void |
| 161 | s_stab_generic (what, stab_secname, stabstr_secname) |
| 162 | int what; |
| 163 | char *stab_secname; |
| 164 | char *stabstr_secname; |
| 165 | { |
| 166 | long longint; |
| 167 | char *string; |
| 168 | int type; |
| 169 | int other; |
| 170 | int desc; |
| 171 | |
| 172 | /* The general format is: |
| 173 | .stabs "STRING",TYPE,OTHER,DESC,VALUE |
| 174 | .stabn TYPE,OTHER,DESC,VALUE |
| 175 | .stabd TYPE,OTHER,DESC |
| 176 | At this point input_line_pointer points after the pseudo-op and |
| 177 | any trailing whitespace. The argument what is one of 's', 'n' or |
| 178 | 'd' indicating which type of .stab this is. */ |
| 179 | |
| 180 | if (what != 's') |
| 181 | string = ""; |
| 182 | else |
| 183 | { |
| 184 | int length; |
| 185 | |
| 186 | string = demand_copy_C_string (&length); |
| 187 | SKIP_WHITESPACE (); |
| 188 | if (*input_line_pointer == ',') |
| 189 | input_line_pointer++; |
| 190 | else |
| 191 | { |
| 192 | as_warn (".stabs: Missing comma"); |
| 193 | ignore_rest_of_line (); |
| 194 | return; |
| 195 | } |
| 196 | } |
| 197 | |
| 198 | if (get_absolute_expression_and_terminator (&longint) != ',') |
| 199 | { |
| 200 | as_warn (".stab%c: Missing comma", what); |
| 201 | ignore_rest_of_line (); |
| 202 | return; |
| 203 | } |
| 204 | type = longint; |
| 205 | |
| 206 | if (get_absolute_expression_and_terminator (&longint) != ',') |
| 207 | { |
| 208 | as_warn (".stab%c: Missing comma", what); |
| 209 | ignore_rest_of_line (); |
| 210 | return; |
| 211 | } |
| 212 | other = longint; |
| 213 | |
| 214 | desc = get_absolute_expression (); |
| 215 | if (what == 's' || what == 'n') |
| 216 | { |
| 217 | if (*input_line_pointer != ',') |
| 218 | { |
| 219 | as_warn (".stab%c: Missing comma", what); |
| 220 | ignore_rest_of_line (); |
| 221 | return; |
| 222 | } |
| 223 | input_line_pointer++; |
| 224 | SKIP_WHITESPACE (); |
| 225 | } |
| 226 | |
| 227 | #ifdef TC_PPC |
| 228 | #ifdef OBJ_ELF |
| 229 | /* Solaris on PowerPC has decided that .stabd takes 4 arguments, so emulate it. */ |
| 230 | else if (what == 'd') |
| 231 | { |
| 232 | char *save_location = input_line_pointer; |
| 233 | |
| 234 | SKIP_WHITESPACE (); |
| 235 | if (*input_line_pointer == ',') |
| 236 | { |
| 237 | int dummy; |
| 238 | |
| 239 | input_line_pointer++; |
| 240 | SKIP_WHITESPACE (); |
| 241 | |
| 242 | dummy = get_absolute_expression (); |
| 243 | if (dummy != 0) |
| 244 | { |
| 245 | as_warn (".stabd: Fourth field must be 0"); |
| 246 | ignore_rest_of_line (); |
| 247 | return; |
| 248 | } |
| 249 | SKIP_WHITESPACE (); |
| 250 | } |
| 251 | else |
| 252 | input_line_pointer = save_location; |
| 253 | } |
| 254 | #endif /* OBJ_ELF */ |
| 255 | #endif /* TC_PPC */ |
| 256 | |
| 257 | #ifndef NO_LISTING |
| 258 | if (listing) |
| 259 | { |
| 260 | switch (type) |
| 261 | { |
| 262 | case N_SLINE: |
| 263 | listing_source_line ((unsigned int) desc); |
| 264 | break; |
| 265 | case N_SO: |
| 266 | case N_SOL: |
| 267 | listing_source_file (string); |
| 268 | break; |
| 269 | } |
| 270 | } |
| 271 | #endif /* ! NO_LISTING */ |
| 272 | |
| 273 | /* We have now gathered the type, other, and desc information. For |
| 274 | .stabs or .stabn, input_line_pointer is now pointing at the |
| 275 | value. */ |
| 276 | |
| 277 | if (SEPARATE_STAB_SECTIONS) |
| 278 | /* Output the stab information in a separate section. This is used |
| 279 | at least for COFF and ELF. */ |
| 280 | { |
| 281 | segT saved_seg = now_seg; |
| 282 | subsegT saved_subseg = now_subseg; |
| 283 | fragS *saved_frag = frag_now; |
| 284 | valueT dot; |
| 285 | segT seg; |
| 286 | unsigned int stroff; |
| 287 | char *p; |
| 288 | |
| 289 | static segT cached_sec; |
| 290 | static char *cached_secname; |
| 291 | |
| 292 | dot = frag_now_fix (); |
| 293 | |
| 294 | if (cached_secname && !strcmp (cached_secname, stab_secname)) |
| 295 | { |
| 296 | seg = cached_sec; |
| 297 | subseg_set (seg, 0); |
| 298 | } |
| 299 | else |
| 300 | { |
| 301 | seg = subseg_new (stab_secname, 0); |
| 302 | if (cached_secname) |
| 303 | free (cached_secname); |
| 304 | cached_secname = xstrdup (stab_secname); |
| 305 | cached_sec = seg; |
| 306 | } |
| 307 | |
| 308 | if (! seg_info (seg)->hadone) |
| 309 | { |
| 310 | #ifdef BFD_ASSEMBLER |
| 311 | bfd_set_section_flags (stdoutput, seg, |
| 312 | SEC_READONLY | SEC_RELOC | SEC_DEBUGGING); |
| 313 | #endif |
| 314 | #ifdef INIT_STAB_SECTION |
| 315 | INIT_STAB_SECTION (seg); |
| 316 | #endif |
| 317 | seg_info (seg)->hadone = 1; |
| 318 | } |
| 319 | |
| 320 | stroff = get_stab_string_offset (string, stabstr_secname); |
| 321 | if (what == 's') |
| 322 | { |
| 323 | /* release the string */ |
| 324 | obstack_free (¬es, string); |
| 325 | } |
| 326 | |
| 327 | /* At least for now, stabs in a special stab section are always |
| 328 | output as 12 byte blocks of information. */ |
| 329 | p = frag_more (8); |
| 330 | md_number_to_chars (p, (valueT) stroff, 4); |
| 331 | md_number_to_chars (p + 4, (valueT) type, 1); |
| 332 | md_number_to_chars (p + 5, (valueT) other, 1); |
| 333 | md_number_to_chars (p + 6, (valueT) desc, 2); |
| 334 | |
| 335 | if (what == 's' || what == 'n') |
| 336 | { |
| 337 | /* Pick up the value from the input line. */ |
| 338 | cons (4); |
| 339 | input_line_pointer--; |
| 340 | } |
| 341 | else |
| 342 | { |
| 343 | const char *fake; |
| 344 | symbolS *symbol; |
| 345 | expressionS exp; |
| 346 | |
| 347 | /* Arrange for a value representing the current location. */ |
| 348 | fake = FAKE_LABEL_NAME; |
| 349 | symbol = symbol_new (fake, saved_seg, dot, saved_frag); |
| 350 | |
| 351 | exp.X_op = O_symbol; |
| 352 | exp.X_add_symbol = symbol; |
| 353 | exp.X_add_number = 0; |
| 354 | |
| 355 | emit_expr (&exp, 4); |
| 356 | } |
| 357 | |
| 358 | #ifdef OBJ_PROCESS_STAB |
| 359 | OBJ_PROCESS_STAB (seg, what, string, type, other, desc); |
| 360 | #endif |
| 361 | |
| 362 | subseg_set (saved_seg, saved_subseg); |
| 363 | } |
| 364 | else |
| 365 | { |
| 366 | #ifdef OBJ_PROCESS_STAB |
| 367 | OBJ_PROCESS_STAB (0, what, string, type, other, desc); |
| 368 | #else |
| 369 | abort (); |
| 370 | #endif |
| 371 | } |
| 372 | |
| 373 | demand_empty_rest_of_line (); |
| 374 | } |
| 375 | |
| 376 | /* Regular stab directive. */ |
| 377 | |
| 378 | void |
| 379 | s_stab (what) |
| 380 | int what; |
| 381 | { |
| 382 | s_stab_generic (what, STAB_SECTION_NAME, STAB_STRING_SECTION_NAME); |
| 383 | } |
| 384 | |
| 385 | /* "Extended stabs", used in Solaris only now. */ |
| 386 | |
| 387 | void |
| 388 | s_xstab (what) |
| 389 | int what; |
| 390 | { |
| 391 | int length; |
| 392 | char *stab_secname, *stabstr_secname; |
| 393 | static char *saved_secname, *saved_strsecname; |
| 394 | |
| 395 | /* @@ MEMORY LEAK: This allocates a copy of the string, but in most |
| 396 | cases it will be the same string, so we could release the storage |
| 397 | back to the obstack it came from. */ |
| 398 | stab_secname = demand_copy_C_string (&length); |
| 399 | SKIP_WHITESPACE (); |
| 400 | if (*input_line_pointer == ',') |
| 401 | input_line_pointer++; |
| 402 | else |
| 403 | { |
| 404 | as_bad ("comma missing in .xstabs"); |
| 405 | ignore_rest_of_line (); |
| 406 | return; |
| 407 | } |
| 408 | |
| 409 | /* To get the name of the stab string section, simply add "str" to |
| 410 | the stab section name. */ |
| 411 | if (saved_secname == 0 || strcmp (saved_secname, stab_secname)) |
| 412 | { |
| 413 | stabstr_secname = (char *) xmalloc (strlen (stab_secname) + 4); |
| 414 | strcpy (stabstr_secname, stab_secname); |
| 415 | strcat (stabstr_secname, "str"); |
| 416 | if (saved_secname) |
| 417 | { |
| 418 | free (saved_secname); |
| 419 | free (saved_strsecname); |
| 420 | } |
| 421 | saved_secname = stab_secname; |
| 422 | saved_strsecname = stabstr_secname; |
| 423 | } |
| 424 | s_stab_generic (what, saved_secname, saved_strsecname); |
| 425 | } |
| 426 | |
| 427 | #ifdef S_SET_DESC |
| 428 | |
| 429 | /* Frob invented at RMS' request. Set the n_desc of a symbol. */ |
| 430 | |
| 431 | void |
| 432 | s_desc (ignore) |
| 433 | int ignore; |
| 434 | { |
| 435 | char *name; |
| 436 | char c; |
| 437 | char *p; |
| 438 | symbolS *symbolP; |
| 439 | int temp; |
| 440 | |
| 441 | name = input_line_pointer; |
| 442 | c = get_symbol_end (); |
| 443 | p = input_line_pointer; |
| 444 | *p = c; |
| 445 | SKIP_WHITESPACE (); |
| 446 | if (*input_line_pointer != ',') |
| 447 | { |
| 448 | *p = 0; |
| 449 | as_bad ("Expected comma after name \"%s\"", name); |
| 450 | *p = c; |
| 451 | ignore_rest_of_line (); |
| 452 | } |
| 453 | else |
| 454 | { |
| 455 | input_line_pointer++; |
| 456 | temp = get_absolute_expression (); |
| 457 | *p = 0; |
| 458 | symbolP = symbol_find_or_make (name); |
| 459 | *p = c; |
| 460 | S_SET_DESC (symbolP, temp); |
| 461 | } |
| 462 | demand_empty_rest_of_line (); |
| 463 | } /* s_desc() */ |
| 464 | |
| 465 | #endif /* defined (S_SET_DESC) */ |