| 1 | /* cond.c - conditional assembly pseudo-ops, and .include |
| 2 | Copyright (C) 1990-2014 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 published by |
| 8 | the Free Software Foundation; either version 3, or (at your option) |
| 9 | any later version. |
| 10 | |
| 11 | GAS 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 GAS; see the file COPYING. If not, write to the Free |
| 18 | Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA |
| 19 | 02110-1301, USA. */ |
| 20 | |
| 21 | #include "as.h" |
| 22 | #include "sb.h" |
| 23 | #include "macro.h" |
| 24 | |
| 25 | #include "obstack.h" |
| 26 | |
| 27 | /* This is allocated to grow and shrink as .ifdef/.endif pairs are |
| 28 | scanned. */ |
| 29 | struct obstack cond_obstack; |
| 30 | |
| 31 | struct file_line { |
| 32 | char *file; |
| 33 | unsigned int line; |
| 34 | }; |
| 35 | |
| 36 | /* We push one of these structures for each .if, and pop it at the |
| 37 | .endif. */ |
| 38 | |
| 39 | struct conditional_frame { |
| 40 | /* The source file & line number of the "if". */ |
| 41 | struct file_line if_file_line; |
| 42 | /* The source file & line of the "else". */ |
| 43 | struct file_line else_file_line; |
| 44 | /* The previous conditional. */ |
| 45 | struct conditional_frame *previous_cframe; |
| 46 | /* Have we seen an else yet? */ |
| 47 | int else_seen; |
| 48 | /* Whether we are currently ignoring input. */ |
| 49 | int ignoring; |
| 50 | /* Whether a conditional at a higher level is ignoring input. |
| 51 | Set also when a branch of an "if .. elseif .." tree has matched |
| 52 | to prevent further matches. */ |
| 53 | int dead_tree; |
| 54 | /* Macro nesting level at which this conditional was created. */ |
| 55 | int macro_nest; |
| 56 | }; |
| 57 | |
| 58 | static void initialize_cframe (struct conditional_frame *cframe); |
| 59 | static char *get_mri_string (int, int *); |
| 60 | |
| 61 | static struct conditional_frame *current_cframe = NULL; |
| 62 | |
| 63 | /* Performs the .ifdef (test_defined == 1) and |
| 64 | the .ifndef (test_defined == 0) pseudo op. */ |
| 65 | |
| 66 | void |
| 67 | s_ifdef (int test_defined) |
| 68 | { |
| 69 | /* Points to name of symbol. */ |
| 70 | char *name; |
| 71 | /* Points to symbol. */ |
| 72 | symbolS *symbolP; |
| 73 | struct conditional_frame cframe; |
| 74 | char c; |
| 75 | |
| 76 | /* Leading whitespace is part of operand. */ |
| 77 | SKIP_WHITESPACE (); |
| 78 | name = input_line_pointer; |
| 79 | |
| 80 | if (!is_name_beginner (*name)) |
| 81 | { |
| 82 | as_bad (_("invalid identifier for \".ifdef\"")); |
| 83 | obstack_1grow (&cond_obstack, 0); |
| 84 | ignore_rest_of_line (); |
| 85 | return; |
| 86 | } |
| 87 | |
| 88 | c = get_symbol_end (); |
| 89 | symbolP = symbol_find (name); |
| 90 | *input_line_pointer = c; |
| 91 | |
| 92 | initialize_cframe (&cframe); |
| 93 | |
| 94 | if (cframe.dead_tree) |
| 95 | cframe.ignoring = 1; |
| 96 | else |
| 97 | { |
| 98 | int is_defined; |
| 99 | |
| 100 | /* Use the same definition of 'defined' as .equiv so that a symbol |
| 101 | which has been referenced but not yet given a value/address is |
| 102 | considered to be undefined. */ |
| 103 | is_defined = |
| 104 | symbolP != NULL |
| 105 | && (S_IS_DEFINED (symbolP) || symbol_equated_p (symbolP)) |
| 106 | && S_GET_SEGMENT (symbolP) != reg_section; |
| 107 | |
| 108 | cframe.ignoring = ! (test_defined ^ is_defined); |
| 109 | } |
| 110 | |
| 111 | current_cframe = ((struct conditional_frame *) |
| 112 | obstack_copy (&cond_obstack, &cframe, |
| 113 | sizeof (cframe))); |
| 114 | |
| 115 | if (LISTING_SKIP_COND () |
| 116 | && cframe.ignoring |
| 117 | && (cframe.previous_cframe == NULL |
| 118 | || ! cframe.previous_cframe->ignoring)) |
| 119 | listing_list (2); |
| 120 | |
| 121 | demand_empty_rest_of_line (); |
| 122 | } |
| 123 | |
| 124 | void |
| 125 | s_if (int arg) |
| 126 | { |
| 127 | expressionS operand; |
| 128 | struct conditional_frame cframe; |
| 129 | int t; |
| 130 | char *stop = NULL; |
| 131 | char stopc; |
| 132 | |
| 133 | if (flag_mri) |
| 134 | stop = mri_comment_field (&stopc); |
| 135 | |
| 136 | /* Leading whitespace is part of operand. */ |
| 137 | SKIP_WHITESPACE (); |
| 138 | |
| 139 | if (current_cframe != NULL && current_cframe->ignoring) |
| 140 | { |
| 141 | operand.X_add_number = 0; |
| 142 | while (! is_end_of_line[(unsigned char) *input_line_pointer]) |
| 143 | ++input_line_pointer; |
| 144 | } |
| 145 | else |
| 146 | { |
| 147 | expression_and_evaluate (&operand); |
| 148 | if (operand.X_op != O_constant) |
| 149 | as_bad (_("non-constant expression in \".if\" statement")); |
| 150 | } |
| 151 | |
| 152 | switch ((operatorT) arg) |
| 153 | { |
| 154 | case O_eq: t = operand.X_add_number == 0; break; |
| 155 | case O_ne: t = operand.X_add_number != 0; break; |
| 156 | case O_lt: t = operand.X_add_number < 0; break; |
| 157 | case O_le: t = operand.X_add_number <= 0; break; |
| 158 | case O_ge: t = operand.X_add_number >= 0; break; |
| 159 | case O_gt: t = operand.X_add_number > 0; break; |
| 160 | default: |
| 161 | abort (); |
| 162 | return; |
| 163 | } |
| 164 | |
| 165 | /* If the above error is signaled, this will dispatch |
| 166 | using an undefined result. No big deal. */ |
| 167 | initialize_cframe (&cframe); |
| 168 | cframe.ignoring = cframe.dead_tree || ! t; |
| 169 | current_cframe = ((struct conditional_frame *) |
| 170 | obstack_copy (&cond_obstack, &cframe, sizeof (cframe))); |
| 171 | |
| 172 | if (LISTING_SKIP_COND () |
| 173 | && cframe.ignoring |
| 174 | && (cframe.previous_cframe == NULL |
| 175 | || ! cframe.previous_cframe->ignoring)) |
| 176 | listing_list (2); |
| 177 | |
| 178 | if (flag_mri) |
| 179 | mri_comment_end (stop, stopc); |
| 180 | |
| 181 | demand_empty_rest_of_line (); |
| 182 | } |
| 183 | |
| 184 | /* Performs the .ifb (test_blank == 1) and |
| 185 | the .ifnb (test_blank == 0) pseudo op. */ |
| 186 | |
| 187 | void |
| 188 | s_ifb (int test_blank) |
| 189 | { |
| 190 | struct conditional_frame cframe; |
| 191 | |
| 192 | initialize_cframe (&cframe); |
| 193 | |
| 194 | if (cframe.dead_tree) |
| 195 | cframe.ignoring = 1; |
| 196 | else |
| 197 | { |
| 198 | int is_eol; |
| 199 | |
| 200 | SKIP_WHITESPACE (); |
| 201 | is_eol = is_end_of_line[(unsigned char) *input_line_pointer]; |
| 202 | cframe.ignoring = (test_blank == !is_eol); |
| 203 | } |
| 204 | |
| 205 | current_cframe = ((struct conditional_frame *) |
| 206 | obstack_copy (&cond_obstack, &cframe, |
| 207 | sizeof (cframe))); |
| 208 | |
| 209 | if (LISTING_SKIP_COND () |
| 210 | && cframe.ignoring |
| 211 | && (cframe.previous_cframe == NULL |
| 212 | || ! cframe.previous_cframe->ignoring)) |
| 213 | listing_list (2); |
| 214 | |
| 215 | ignore_rest_of_line (); |
| 216 | } |
| 217 | |
| 218 | /* Get a string for the MRI IFC or IFNC pseudo-ops. */ |
| 219 | |
| 220 | static char * |
| 221 | get_mri_string (int terminator, int *len) |
| 222 | { |
| 223 | char *ret; |
| 224 | char *s; |
| 225 | |
| 226 | SKIP_WHITESPACE (); |
| 227 | s = ret = input_line_pointer; |
| 228 | if (*input_line_pointer == '\'') |
| 229 | { |
| 230 | ++s; |
| 231 | ++input_line_pointer; |
| 232 | while (! is_end_of_line[(unsigned char) *input_line_pointer]) |
| 233 | { |
| 234 | *s++ = *input_line_pointer++; |
| 235 | if (s[-1] == '\'') |
| 236 | { |
| 237 | if (*input_line_pointer != '\'') |
| 238 | break; |
| 239 | ++input_line_pointer; |
| 240 | } |
| 241 | } |
| 242 | SKIP_WHITESPACE (); |
| 243 | } |
| 244 | else |
| 245 | { |
| 246 | while (*input_line_pointer != terminator |
| 247 | && ! is_end_of_line[(unsigned char) *input_line_pointer]) |
| 248 | ++input_line_pointer; |
| 249 | s = input_line_pointer; |
| 250 | while (s > ret && (s[-1] == ' ' || s[-1] == '\t')) |
| 251 | --s; |
| 252 | } |
| 253 | |
| 254 | *len = s - ret; |
| 255 | return ret; |
| 256 | } |
| 257 | |
| 258 | /* The MRI IFC and IFNC pseudo-ops. */ |
| 259 | |
| 260 | void |
| 261 | s_ifc (int arg) |
| 262 | { |
| 263 | char *stop = NULL; |
| 264 | char stopc; |
| 265 | char *s1, *s2; |
| 266 | int len1, len2; |
| 267 | int res; |
| 268 | struct conditional_frame cframe; |
| 269 | |
| 270 | if (flag_mri) |
| 271 | stop = mri_comment_field (&stopc); |
| 272 | |
| 273 | s1 = get_mri_string (',', &len1); |
| 274 | |
| 275 | if (*input_line_pointer != ',') |
| 276 | as_bad (_("bad format for ifc or ifnc")); |
| 277 | else |
| 278 | ++input_line_pointer; |
| 279 | |
| 280 | s2 = get_mri_string (';', &len2); |
| 281 | |
| 282 | res = len1 == len2 && strncmp (s1, s2, len1) == 0; |
| 283 | |
| 284 | initialize_cframe (&cframe); |
| 285 | cframe.ignoring = cframe.dead_tree || ! (res ^ arg); |
| 286 | current_cframe = ((struct conditional_frame *) |
| 287 | obstack_copy (&cond_obstack, &cframe, sizeof (cframe))); |
| 288 | |
| 289 | if (LISTING_SKIP_COND () |
| 290 | && cframe.ignoring |
| 291 | && (cframe.previous_cframe == NULL |
| 292 | || ! cframe.previous_cframe->ignoring)) |
| 293 | listing_list (2); |
| 294 | |
| 295 | if (flag_mri) |
| 296 | mri_comment_end (stop, stopc); |
| 297 | |
| 298 | demand_empty_rest_of_line (); |
| 299 | } |
| 300 | |
| 301 | void |
| 302 | s_elseif (int arg) |
| 303 | { |
| 304 | if (current_cframe == NULL) |
| 305 | { |
| 306 | as_bad (_("\".elseif\" without matching \".if\"")); |
| 307 | } |
| 308 | else if (current_cframe->else_seen) |
| 309 | { |
| 310 | as_bad (_("\".elseif\" after \".else\"")); |
| 311 | as_bad_where (current_cframe->else_file_line.file, |
| 312 | current_cframe->else_file_line.line, |
| 313 | _("here is the previous \".else\"")); |
| 314 | as_bad_where (current_cframe->if_file_line.file, |
| 315 | current_cframe->if_file_line.line, |
| 316 | _("here is the previous \".if\"")); |
| 317 | } |
| 318 | else |
| 319 | { |
| 320 | as_where (¤t_cframe->else_file_line.file, |
| 321 | ¤t_cframe->else_file_line.line); |
| 322 | |
| 323 | current_cframe->dead_tree |= !current_cframe->ignoring; |
| 324 | current_cframe->ignoring = current_cframe->dead_tree; |
| 325 | } |
| 326 | |
| 327 | if (current_cframe == NULL || current_cframe->ignoring) |
| 328 | { |
| 329 | while (! is_end_of_line[(unsigned char) *input_line_pointer]) |
| 330 | ++input_line_pointer; |
| 331 | |
| 332 | if (current_cframe == NULL) |
| 333 | return; |
| 334 | } |
| 335 | else |
| 336 | { |
| 337 | expressionS operand; |
| 338 | int t; |
| 339 | |
| 340 | /* Leading whitespace is part of operand. */ |
| 341 | SKIP_WHITESPACE (); |
| 342 | |
| 343 | expression_and_evaluate (&operand); |
| 344 | if (operand.X_op != O_constant) |
| 345 | as_bad (_("non-constant expression in \".elseif\" statement")); |
| 346 | |
| 347 | switch ((operatorT) arg) |
| 348 | { |
| 349 | case O_eq: t = operand.X_add_number == 0; break; |
| 350 | case O_ne: t = operand.X_add_number != 0; break; |
| 351 | case O_lt: t = operand.X_add_number < 0; break; |
| 352 | case O_le: t = operand.X_add_number <= 0; break; |
| 353 | case O_ge: t = operand.X_add_number >= 0; break; |
| 354 | case O_gt: t = operand.X_add_number > 0; break; |
| 355 | default: |
| 356 | abort (); |
| 357 | return; |
| 358 | } |
| 359 | |
| 360 | current_cframe->ignoring = current_cframe->dead_tree || ! t; |
| 361 | } |
| 362 | |
| 363 | if (LISTING_SKIP_COND () |
| 364 | && (current_cframe->previous_cframe == NULL |
| 365 | || ! current_cframe->previous_cframe->ignoring)) |
| 366 | { |
| 367 | if (! current_cframe->ignoring) |
| 368 | listing_list (1); |
| 369 | else |
| 370 | listing_list (2); |
| 371 | } |
| 372 | |
| 373 | demand_empty_rest_of_line (); |
| 374 | } |
| 375 | |
| 376 | void |
| 377 | s_endif (int arg ATTRIBUTE_UNUSED) |
| 378 | { |
| 379 | struct conditional_frame *hold; |
| 380 | |
| 381 | if (current_cframe == NULL) |
| 382 | { |
| 383 | as_bad (_("\".endif\" without \".if\"")); |
| 384 | } |
| 385 | else |
| 386 | { |
| 387 | if (LISTING_SKIP_COND () |
| 388 | && current_cframe->ignoring |
| 389 | && (current_cframe->previous_cframe == NULL |
| 390 | || ! current_cframe->previous_cframe->ignoring)) |
| 391 | listing_list (1); |
| 392 | |
| 393 | hold = current_cframe; |
| 394 | current_cframe = current_cframe->previous_cframe; |
| 395 | obstack_free (&cond_obstack, hold); |
| 396 | } /* if one pop too many */ |
| 397 | |
| 398 | if (flag_mri) |
| 399 | { |
| 400 | while (! is_end_of_line[(unsigned char) *input_line_pointer]) |
| 401 | ++input_line_pointer; |
| 402 | } |
| 403 | |
| 404 | demand_empty_rest_of_line (); |
| 405 | } |
| 406 | |
| 407 | void |
| 408 | s_else (int arg ATTRIBUTE_UNUSED) |
| 409 | { |
| 410 | if (current_cframe == NULL) |
| 411 | { |
| 412 | as_bad (_("\".else\" without matching \".if\"")); |
| 413 | } |
| 414 | else if (current_cframe->else_seen) |
| 415 | { |
| 416 | as_bad (_("duplicate \".else\"")); |
| 417 | as_bad_where (current_cframe->else_file_line.file, |
| 418 | current_cframe->else_file_line.line, |
| 419 | _("here is the previous \".else\"")); |
| 420 | as_bad_where (current_cframe->if_file_line.file, |
| 421 | current_cframe->if_file_line.line, |
| 422 | _("here is the previous \".if\"")); |
| 423 | } |
| 424 | else |
| 425 | { |
| 426 | as_where (¤t_cframe->else_file_line.file, |
| 427 | ¤t_cframe->else_file_line.line); |
| 428 | |
| 429 | current_cframe->ignoring = |
| 430 | current_cframe->dead_tree | !current_cframe->ignoring; |
| 431 | |
| 432 | if (LISTING_SKIP_COND () |
| 433 | && (current_cframe->previous_cframe == NULL |
| 434 | || ! current_cframe->previous_cframe->ignoring)) |
| 435 | { |
| 436 | if (! current_cframe->ignoring) |
| 437 | listing_list (1); |
| 438 | else |
| 439 | listing_list (2); |
| 440 | } |
| 441 | |
| 442 | current_cframe->else_seen = 1; |
| 443 | } |
| 444 | |
| 445 | if (flag_mri) |
| 446 | { |
| 447 | while (! is_end_of_line[(unsigned char) *input_line_pointer]) |
| 448 | ++input_line_pointer; |
| 449 | } |
| 450 | |
| 451 | demand_empty_rest_of_line (); |
| 452 | } |
| 453 | |
| 454 | void |
| 455 | s_ifeqs (int arg) |
| 456 | { |
| 457 | char *s1, *s2; |
| 458 | int len1, len2; |
| 459 | int res; |
| 460 | struct conditional_frame cframe; |
| 461 | |
| 462 | s1 = demand_copy_C_string (&len1); |
| 463 | |
| 464 | SKIP_WHITESPACE (); |
| 465 | if (*input_line_pointer != ',') |
| 466 | { |
| 467 | as_bad (_(".ifeqs syntax error")); |
| 468 | ignore_rest_of_line (); |
| 469 | return; |
| 470 | } |
| 471 | |
| 472 | ++input_line_pointer; |
| 473 | |
| 474 | s2 = demand_copy_C_string (&len2); |
| 475 | |
| 476 | res = len1 == len2 && strncmp (s1, s2, len1) == 0; |
| 477 | |
| 478 | initialize_cframe (&cframe); |
| 479 | cframe.ignoring = cframe.dead_tree || ! (res ^ arg); |
| 480 | current_cframe = ((struct conditional_frame *) |
| 481 | obstack_copy (&cond_obstack, &cframe, sizeof (cframe))); |
| 482 | |
| 483 | if (LISTING_SKIP_COND () |
| 484 | && cframe.ignoring |
| 485 | && (cframe.previous_cframe == NULL |
| 486 | || ! cframe.previous_cframe->ignoring)) |
| 487 | listing_list (2); |
| 488 | |
| 489 | demand_empty_rest_of_line (); |
| 490 | } |
| 491 | |
| 492 | int |
| 493 | ignore_input (void) |
| 494 | { |
| 495 | char *s; |
| 496 | |
| 497 | s = input_line_pointer; |
| 498 | |
| 499 | if (NO_PSEUDO_DOT || flag_m68k_mri) |
| 500 | { |
| 501 | if (s[-1] != '.') |
| 502 | --s; |
| 503 | } |
| 504 | else |
| 505 | { |
| 506 | if (s[-1] != '.') |
| 507 | return (current_cframe != NULL) && (current_cframe->ignoring); |
| 508 | } |
| 509 | |
| 510 | /* We cannot ignore certain pseudo ops. */ |
| 511 | if (((s[0] == 'i' |
| 512 | || s[0] == 'I') |
| 513 | && (!strncasecmp (s, "if", 2) |
| 514 | || !strncasecmp (s, "ifdef", 5) |
| 515 | || !strncasecmp (s, "ifndef", 6))) |
| 516 | || ((s[0] == 'e' |
| 517 | || s[0] == 'E') |
| 518 | && (!strncasecmp (s, "else", 4) |
| 519 | || !strncasecmp (s, "endif", 5) |
| 520 | || !strncasecmp (s, "endc", 4)))) |
| 521 | return 0; |
| 522 | |
| 523 | return (current_cframe != NULL) && (current_cframe->ignoring); |
| 524 | } |
| 525 | |
| 526 | static void |
| 527 | initialize_cframe (struct conditional_frame *cframe) |
| 528 | { |
| 529 | memset (cframe, 0, sizeof (*cframe)); |
| 530 | as_where (&cframe->if_file_line.file, |
| 531 | &cframe->if_file_line.line); |
| 532 | cframe->previous_cframe = current_cframe; |
| 533 | cframe->dead_tree = current_cframe != NULL && current_cframe->ignoring; |
| 534 | cframe->macro_nest = macro_nest; |
| 535 | } |
| 536 | |
| 537 | /* Give an error if a conditional is unterminated inside a macro or |
| 538 | the assembly as a whole. If NEST is non negative, we are being |
| 539 | called because of the end of a macro expansion. If NEST is |
| 540 | negative, we are being called at the of the input files. */ |
| 541 | |
| 542 | void |
| 543 | cond_finish_check (int nest) |
| 544 | { |
| 545 | if (current_cframe != NULL && current_cframe->macro_nest >= nest) |
| 546 | { |
| 547 | if (nest >= 0) |
| 548 | as_bad (_("end of macro inside conditional")); |
| 549 | else |
| 550 | as_bad (_("end of file inside conditional")); |
| 551 | as_bad_where (current_cframe->if_file_line.file, |
| 552 | current_cframe->if_file_line.line, |
| 553 | _("here is the start of the unterminated conditional")); |
| 554 | if (current_cframe->else_seen) |
| 555 | as_bad_where (current_cframe->else_file_line.file, |
| 556 | current_cframe->else_file_line.line, |
| 557 | _("here is the \"else\" of the unterminated conditional")); |
| 558 | } |
| 559 | } |
| 560 | |
| 561 | /* This function is called when we exit out of a macro. We assume |
| 562 | that any conditionals which began within the macro are correctly |
| 563 | nested, and just pop them off the stack. */ |
| 564 | |
| 565 | void |
| 566 | cond_exit_macro (int nest) |
| 567 | { |
| 568 | while (current_cframe != NULL && current_cframe->macro_nest >= nest) |
| 569 | { |
| 570 | struct conditional_frame *hold; |
| 571 | |
| 572 | hold = current_cframe; |
| 573 | current_cframe = current_cframe->previous_cframe; |
| 574 | obstack_free (&cond_obstack, hold); |
| 575 | } |
| 576 | } |