| 1 | /* Mach-O object file format |
| 2 | Copyright (C) 2009-2020 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 3, |
| 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 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 | /* Here we handle the mach-o directives that are common to all architectures. |
| 22 | |
| 23 | Most significant are mach-o named sections and a variety of symbol type |
| 24 | decorations. */ |
| 25 | |
| 26 | /* Mach-O supports multiple, named segments each of which may contain |
| 27 | multiple named sections. Thus the concept of subsectioning is |
| 28 | handled by (say) having a __TEXT segment with appropriate flags from |
| 29 | which subsections are generated like __text, __const etc. |
| 30 | |
| 31 | The well-known as short-hand section switch directives like .text, .data |
| 32 | etc. are mapped onto predefined segment/section pairs using facilities |
| 33 | supplied by the mach-o port of bfd. |
| 34 | |
| 35 | A number of additional mach-o short-hand section switch directives are |
| 36 | also defined. */ |
| 37 | |
| 38 | #define OBJ_HEADER "obj-macho.h" |
| 39 | |
| 40 | #include "as.h" |
| 41 | #include "subsegs.h" |
| 42 | #include "symbols.h" |
| 43 | #include "write.h" |
| 44 | #include "mach-o.h" |
| 45 | #include "mach-o/loader.h" |
| 46 | #include "obj-macho.h" |
| 47 | |
| 48 | #include <string.h> |
| 49 | |
| 50 | /* Forward decls. */ |
| 51 | static segT obj_mach_o_segT_from_bfd_name (const char *, int); |
| 52 | |
| 53 | /* TODO: Implement "-dynamic"/"-static" command line options. */ |
| 54 | |
| 55 | static int obj_mach_o_is_static; |
| 56 | |
| 57 | /* TODO: Implement the "-n" command line option to suppress the initial |
| 58 | switch to the text segment. */ |
| 59 | |
| 60 | static int obj_mach_o_start_with_text_section = 1; |
| 61 | |
| 62 | /* Allow for special re-ordering on output. */ |
| 63 | |
| 64 | static int obj_mach_o_seen_objc_section; |
| 65 | |
| 66 | /* Start-up: At present, just create the sections we want. */ |
| 67 | void |
| 68 | mach_o_begin (void) |
| 69 | { |
| 70 | /* Mach-O only defines the .text section by default, and even this can |
| 71 | be suppressed by a flag. In the latter event, the first code MUST |
| 72 | be a section definition. */ |
| 73 | if (obj_mach_o_start_with_text_section) |
| 74 | { |
| 75 | text_section = obj_mach_o_segT_from_bfd_name (TEXT_SECTION_NAME, 1); |
| 76 | subseg_set (text_section, 0); |
| 77 | if (obj_mach_o_is_static) |
| 78 | { |
| 79 | bfd_mach_o_section *mo_sec |
| 80 | = bfd_mach_o_get_mach_o_section (text_section); |
| 81 | mo_sec->flags &= ~BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS; |
| 82 | } |
| 83 | } |
| 84 | } |
| 85 | |
| 86 | /* Remember the subsections_by_symbols state in case we need to reset |
| 87 | the file flags. */ |
| 88 | |
| 89 | static int obj_mach_o_subsections_by_symbols; |
| 90 | |
| 91 | /* This will put at most 16 characters (terminated by a ',' or newline) from |
| 92 | the input stream into dest. If there are more than 16 chars before the |
| 93 | delimiter, a warning is given and the string is truncated. On completion of |
| 94 | this function, input_line_pointer will point to the char after the ',' or |
| 95 | to the newline. |
| 96 | |
| 97 | It trims leading and trailing space. */ |
| 98 | |
| 99 | static int |
| 100 | collect_16char_name (char *dest, const char *msg, int require_comma) |
| 101 | { |
| 102 | char c, *namstart; |
| 103 | |
| 104 | SKIP_WHITESPACE (); |
| 105 | namstart = input_line_pointer; |
| 106 | |
| 107 | while ( (c = *input_line_pointer) != ',' |
| 108 | && !is_end_of_line[(unsigned char) c]) |
| 109 | input_line_pointer++; |
| 110 | |
| 111 | { |
| 112 | int len = input_line_pointer - namstart; /* could be zero. */ |
| 113 | /* lose any trailing space. */ |
| 114 | while (len > 0 && namstart[len-1] == ' ') |
| 115 | len--; |
| 116 | if (len > 16) |
| 117 | { |
| 118 | *input_line_pointer = '\0'; /* make a temp string. */ |
| 119 | as_bad (_("the %s name '%s' is too long (maximum 16 characters)"), |
| 120 | msg, namstart); |
| 121 | *input_line_pointer = c; /* restore for printing. */ |
| 122 | len = 16; |
| 123 | } |
| 124 | if (len > 0) |
| 125 | memcpy (dest, namstart, len); |
| 126 | } |
| 127 | |
| 128 | if (c != ',' && require_comma) |
| 129 | { |
| 130 | as_bad (_("expected a %s name followed by a `,'"), msg); |
| 131 | return 1; |
| 132 | } |
| 133 | |
| 134 | return 0; |
| 135 | } |
| 136 | |
| 137 | static int |
| 138 | obj_mach_o_get_section_names (char *seg, char *sec, |
| 139 | unsigned segl, unsigned secl) |
| 140 | { |
| 141 | /* Zero-length segment and section names are allowed. */ |
| 142 | /* Parse segment name. */ |
| 143 | memset (seg, 0, segl); |
| 144 | if (collect_16char_name (seg, "segment", 1)) |
| 145 | { |
| 146 | ignore_rest_of_line (); |
| 147 | return 0; |
| 148 | } |
| 149 | input_line_pointer++; /* Skip the terminating ',' */ |
| 150 | |
| 151 | /* Parse section name, which can be empty. */ |
| 152 | memset (sec, 0, secl); |
| 153 | collect_16char_name (sec, "section", 0); |
| 154 | return 1; |
| 155 | } |
| 156 | |
| 157 | /* Build (or get) a section from the mach-o description - which includes |
| 158 | optional definitions for type, attributes, alignment and stub size. |
| 159 | |
| 160 | BFD supplies default values for sections which have a canonical name. */ |
| 161 | |
| 162 | #define SECT_TYPE_SPECIFIED 0x0001 |
| 163 | #define SECT_ATTR_SPECIFIED 0x0002 |
| 164 | #define SECT_ALGN_SPECIFIED 0x0004 |
| 165 | #define SECT_STUB_SPECIFIED 0x0008 |
| 166 | |
| 167 | static segT |
| 168 | obj_mach_o_make_or_get_sect (char * segname, char * sectname, |
| 169 | unsigned int specified_mask, |
| 170 | unsigned int usectype, unsigned int usecattr, |
| 171 | unsigned int ualign, offsetT stub_size) |
| 172 | { |
| 173 | unsigned int sectype, secattr, secalign; |
| 174 | flagword oldflags, flags; |
| 175 | const char *name; |
| 176 | segT sec; |
| 177 | bfd_mach_o_section *msect; |
| 178 | const mach_o_section_name_xlat *xlat; |
| 179 | |
| 180 | /* This provides default bfd flags and default mach-o section type and |
| 181 | attributes along with the canonical name. */ |
| 182 | xlat = bfd_mach_o_section_data_for_mach_sect (stdoutput, segname, sectname); |
| 183 | |
| 184 | /* TODO: more checking of whether overrides are actually allowed. */ |
| 185 | |
| 186 | if (xlat != NULL) |
| 187 | { |
| 188 | name = xstrdup (xlat->bfd_name); |
| 189 | sectype = xlat->macho_sectype; |
| 190 | if (specified_mask & SECT_TYPE_SPECIFIED) |
| 191 | { |
| 192 | if ((sectype == BFD_MACH_O_S_ZEROFILL |
| 193 | || sectype == BFD_MACH_O_S_GB_ZEROFILL) |
| 194 | && sectype != usectype) |
| 195 | as_bad (_("cannot override zerofill section type for `%s,%s'"), |
| 196 | segname, sectname); |
| 197 | else |
| 198 | sectype = usectype; |
| 199 | } |
| 200 | secattr = xlat->macho_secattr; |
| 201 | secalign = xlat->sectalign; |
| 202 | flags = xlat->bfd_flags; |
| 203 | } |
| 204 | else |
| 205 | { |
| 206 | /* There is no normal BFD section name for this section. Create one. |
| 207 | The name created doesn't really matter as it will never be written |
| 208 | on disk. */ |
| 209 | name = concat (segname, ".", sectname, (char *) NULL); |
| 210 | if (specified_mask & SECT_TYPE_SPECIFIED) |
| 211 | sectype = usectype; |
| 212 | else |
| 213 | sectype = BFD_MACH_O_S_REGULAR; |
| 214 | secattr = BFD_MACH_O_S_ATTR_NONE; |
| 215 | secalign = 0; |
| 216 | flags = SEC_NO_FLAGS; |
| 217 | } |
| 218 | |
| 219 | /* For now, just use what the user provided. */ |
| 220 | |
| 221 | if (specified_mask & SECT_ATTR_SPECIFIED) |
| 222 | secattr = usecattr; |
| 223 | |
| 224 | if (specified_mask & SECT_ALGN_SPECIFIED) |
| 225 | secalign = ualign; |
| 226 | |
| 227 | /* Sub-segments don't exists as is on Mach-O. */ |
| 228 | sec = subseg_new (name, 0); |
| 229 | |
| 230 | oldflags = bfd_section_flags (sec); |
| 231 | msect = bfd_mach_o_get_mach_o_section (sec); |
| 232 | |
| 233 | if (oldflags == SEC_NO_FLAGS) |
| 234 | { |
| 235 | /* In the absence of canonical information, try to determine CODE and |
| 236 | DEBUG section flags from the mach-o section data. */ |
| 237 | if (flags == SEC_NO_FLAGS |
| 238 | && (specified_mask & SECT_ATTR_SPECIFIED) |
| 239 | && (secattr & BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS)) |
| 240 | flags |= SEC_CODE; |
| 241 | |
| 242 | if (flags == SEC_NO_FLAGS |
| 243 | && (specified_mask & SECT_ATTR_SPECIFIED) |
| 244 | && (secattr & BFD_MACH_O_S_ATTR_DEBUG)) |
| 245 | flags |= SEC_DEBUGGING; |
| 246 | |
| 247 | /* New, so just use the defaults or what's specified. */ |
| 248 | if (!bfd_set_section_flags (sec, flags)) |
| 249 | as_warn (_("failed to set flags for \"%s\": %s"), |
| 250 | bfd_section_name (sec), |
| 251 | bfd_errmsg (bfd_get_error ())); |
| 252 | |
| 253 | strncpy (msect->segname, segname, BFD_MACH_O_SEGNAME_SIZE); |
| 254 | msect->segname[BFD_MACH_O_SEGNAME_SIZE] = 0; |
| 255 | strncpy (msect->sectname, sectname, BFD_MACH_O_SECTNAME_SIZE); |
| 256 | msect->sectname[BFD_MACH_O_SECTNAME_SIZE] = 0; |
| 257 | |
| 258 | msect->align = secalign; |
| 259 | msect->flags = sectype | secattr; |
| 260 | |
| 261 | if (sectype == BFD_MACH_O_S_ZEROFILL |
| 262 | || sectype == BFD_MACH_O_S_GB_ZEROFILL) |
| 263 | seg_info (sec)->bss = 1; |
| 264 | } |
| 265 | else if (flags != SEC_NO_FLAGS) |
| 266 | { |
| 267 | if (flags != oldflags |
| 268 | || msect->flags != (secattr | sectype)) |
| 269 | as_warn (_("Ignoring changed section attributes for %s"), name); |
| 270 | } |
| 271 | |
| 272 | if (specified_mask & SECT_STUB_SPECIFIED) |
| 273 | /* At present, the stub size is not supplied from the BFD tables. */ |
| 274 | msect->reserved2 = stub_size; |
| 275 | |
| 276 | return sec; |
| 277 | } |
| 278 | |
| 279 | /* .section |
| 280 | |
| 281 | The '.section' specification syntax looks like: |
| 282 | .section <segment> , <section> [, type [, attribs [, size]]] |
| 283 | |
| 284 | White space is allowed everywhere between elements. |
| 285 | |
| 286 | <segment> and <section> may be from 0 to 16 chars in length - they may |
| 287 | contain spaces but leading and trailing space will be trimmed. It is |
| 288 | mandatory that they be present (or that zero-length names are indicated |
| 289 | by ",,"). |
| 290 | |
| 291 | There is only a single section type for any entry. |
| 292 | |
| 293 | There may be multiple attributes, they are delimited by `+'. |
| 294 | |
| 295 | Not all section types and attributes are accepted by the Darwin system |
| 296 | assemblers as user-specifiable - although, at present, we do here. */ |
| 297 | |
| 298 | static void |
| 299 | obj_mach_o_section (int ignore ATTRIBUTE_UNUSED) |
| 300 | { |
| 301 | unsigned int sectype = BFD_MACH_O_S_REGULAR; |
| 302 | unsigned int specified_mask = 0; |
| 303 | unsigned int secattr = 0; |
| 304 | offsetT sizeof_stub = 0; |
| 305 | segT new_seg; |
| 306 | char segname[17]; |
| 307 | char sectname[17]; |
| 308 | |
| 309 | #ifdef md_flush_pending_output |
| 310 | md_flush_pending_output (); |
| 311 | #endif |
| 312 | |
| 313 | /* Get the User's segment and section names. */ |
| 314 | if (! obj_mach_o_get_section_names (segname, sectname, 17, 17)) |
| 315 | return; |
| 316 | |
| 317 | /* Parse section type, if present. */ |
| 318 | if (*input_line_pointer == ',') |
| 319 | { |
| 320 | char *p; |
| 321 | char c; |
| 322 | char tmpc; |
| 323 | int len; |
| 324 | input_line_pointer++; |
| 325 | SKIP_WHITESPACE (); |
| 326 | p = input_line_pointer; |
| 327 | while ((c = *input_line_pointer) != ',' |
| 328 | && !is_end_of_line[(unsigned char) c]) |
| 329 | input_line_pointer++; |
| 330 | |
| 331 | len = input_line_pointer - p; |
| 332 | /* strip trailing spaces. */ |
| 333 | while (len > 0 && p[len-1] == ' ') |
| 334 | len--; |
| 335 | tmpc = p[len]; |
| 336 | |
| 337 | /* Temporarily make a string from the token. */ |
| 338 | p[len] = 0; |
| 339 | sectype = bfd_mach_o_get_section_type_from_name (stdoutput, p); |
| 340 | if (sectype > 255) /* Max Section ID == 255. */ |
| 341 | { |
| 342 | as_bad (_("unknown or invalid section type '%s'"), p); |
| 343 | p[len] = tmpc; |
| 344 | ignore_rest_of_line (); |
| 345 | return; |
| 346 | } |
| 347 | else |
| 348 | specified_mask |= SECT_TYPE_SPECIFIED; |
| 349 | /* Restore. */ |
| 350 | p[len] = tmpc; |
| 351 | |
| 352 | /* Parse attributes. |
| 353 | TODO: check validity of attributes for section type. */ |
| 354 | if ((specified_mask & SECT_TYPE_SPECIFIED) |
| 355 | && c == ',') |
| 356 | { |
| 357 | do |
| 358 | { |
| 359 | int attr; |
| 360 | |
| 361 | /* Skip initial `,' and subsequent `+'. */ |
| 362 | input_line_pointer++; |
| 363 | SKIP_WHITESPACE (); |
| 364 | p = input_line_pointer; |
| 365 | while ((c = *input_line_pointer) != '+' |
| 366 | && c != ',' |
| 367 | && !is_end_of_line[(unsigned char) c]) |
| 368 | input_line_pointer++; |
| 369 | |
| 370 | len = input_line_pointer - p; |
| 371 | /* strip trailing spaces. */ |
| 372 | while (len > 0 && p[len-1] == ' ') |
| 373 | len--; |
| 374 | tmpc = p[len]; |
| 375 | |
| 376 | /* Temporarily make a string from the token. */ |
| 377 | p[len] ='\0'; |
| 378 | attr = bfd_mach_o_get_section_attribute_from_name (p); |
| 379 | if (attr == -1) |
| 380 | { |
| 381 | as_bad (_("unknown or invalid section attribute '%s'"), p); |
| 382 | p[len] = tmpc; |
| 383 | ignore_rest_of_line (); |
| 384 | return; |
| 385 | } |
| 386 | else |
| 387 | { |
| 388 | specified_mask |= SECT_ATTR_SPECIFIED; |
| 389 | secattr |= attr; |
| 390 | } |
| 391 | /* Restore. */ |
| 392 | p[len] = tmpc; |
| 393 | } |
| 394 | while (*input_line_pointer == '+'); |
| 395 | |
| 396 | /* Parse sizeof_stub. */ |
| 397 | if ((specified_mask & SECT_ATTR_SPECIFIED) |
| 398 | && *input_line_pointer == ',') |
| 399 | { |
| 400 | if (sectype != BFD_MACH_O_S_SYMBOL_STUBS) |
| 401 | { |
| 402 | as_bad (_("unexpected section size information")); |
| 403 | ignore_rest_of_line (); |
| 404 | return; |
| 405 | } |
| 406 | |
| 407 | input_line_pointer++; |
| 408 | sizeof_stub = get_absolute_expression (); |
| 409 | specified_mask |= SECT_STUB_SPECIFIED; |
| 410 | } |
| 411 | else if ((specified_mask & SECT_ATTR_SPECIFIED) |
| 412 | && sectype == BFD_MACH_O_S_SYMBOL_STUBS) |
| 413 | { |
| 414 | as_bad (_("missing sizeof_stub expression")); |
| 415 | ignore_rest_of_line (); |
| 416 | return; |
| 417 | } |
| 418 | } |
| 419 | } |
| 420 | |
| 421 | new_seg = obj_mach_o_make_or_get_sect (segname, sectname, specified_mask, |
| 422 | sectype, secattr, 0 /*align */, |
| 423 | sizeof_stub); |
| 424 | if (new_seg != NULL) |
| 425 | { |
| 426 | subseg_set (new_seg, 0); |
| 427 | demand_empty_rest_of_line (); |
| 428 | } |
| 429 | } |
| 430 | |
| 431 | /* .zerofill segname, sectname [, symbolname, size [, align]] |
| 432 | |
| 433 | Zerofill switches, temporarily, to a sect of type 'zerofill'. |
| 434 | |
| 435 | If a variable name is given, it defines that in the section. |
| 436 | Otherwise it just creates the section if it doesn't exist. */ |
| 437 | |
| 438 | static void |
| 439 | obj_mach_o_zerofill (int ignore ATTRIBUTE_UNUSED) |
| 440 | { |
| 441 | char segname[17]; |
| 442 | char sectname[17]; |
| 443 | segT old_seg = now_seg; |
| 444 | segT new_seg; |
| 445 | symbolS *sym = NULL; |
| 446 | unsigned int align = 0; |
| 447 | unsigned int specified_mask = 0; |
| 448 | offsetT size = 0; |
| 449 | |
| 450 | #ifdef md_flush_pending_output |
| 451 | md_flush_pending_output (); |
| 452 | #endif |
| 453 | |
| 454 | /* Get the User's segment and section names. */ |
| 455 | if (! obj_mach_o_get_section_names (segname, sectname, 17, 17)) |
| 456 | return; |
| 457 | |
| 458 | /* Parse variable definition, if present. */ |
| 459 | if (*input_line_pointer == ',') |
| 460 | { |
| 461 | /* Parse symbol, size [.align] |
| 462 | We follow the method of s_common_internal, with the difference |
| 463 | that the symbol cannot be a duplicate-common. */ |
| 464 | char *name; |
| 465 | char c; |
| 466 | char *p; |
| 467 | expressionS exp; |
| 468 | |
| 469 | input_line_pointer++; /* Skip ',' */ |
| 470 | SKIP_WHITESPACE (); |
| 471 | c = get_symbol_name (&name); |
| 472 | /* Just after name is now '\0'. */ |
| 473 | p = input_line_pointer; |
| 474 | *p = c; |
| 475 | |
| 476 | if (name == p) |
| 477 | { |
| 478 | as_bad (_("expected symbol name")); |
| 479 | ignore_rest_of_line (); |
| 480 | goto done; |
| 481 | } |
| 482 | |
| 483 | SKIP_WHITESPACE_AFTER_NAME (); |
| 484 | if (*input_line_pointer == ',') |
| 485 | input_line_pointer++; |
| 486 | |
| 487 | expression_and_evaluate (&exp); |
| 488 | if (exp.X_op != O_constant |
| 489 | && exp.X_op != O_absent) |
| 490 | { |
| 491 | as_bad (_("bad or irreducible absolute expression")); |
| 492 | ignore_rest_of_line (); |
| 493 | goto done; |
| 494 | } |
| 495 | else if (exp.X_op == O_absent) |
| 496 | { |
| 497 | as_bad (_("missing size expression")); |
| 498 | ignore_rest_of_line (); |
| 499 | goto done; |
| 500 | } |
| 501 | |
| 502 | size = exp.X_add_number; |
| 503 | size &= ((offsetT) 2 << (stdoutput->arch_info->bits_per_address - 1)) - 1; |
| 504 | if (exp.X_add_number != size || !exp.X_unsigned) |
| 505 | { |
| 506 | as_warn (_("size (%ld) out of range, ignored"), |
| 507 | (long) exp.X_add_number); |
| 508 | ignore_rest_of_line (); |
| 509 | goto done; |
| 510 | } |
| 511 | |
| 512 | *p = 0; /* Make the name into a c string for err messages. */ |
| 513 | sym = symbol_find_or_make (name); |
| 514 | if (S_IS_DEFINED (sym) || symbol_equated_p (sym)) |
| 515 | { |
| 516 | as_bad (_("symbol `%s' is already defined"), name); |
| 517 | *p = c; |
| 518 | ignore_rest_of_line (); |
| 519 | goto done; |
| 520 | } |
| 521 | |
| 522 | size = S_GET_VALUE (sym); |
| 523 | if (size == 0) |
| 524 | size = exp.X_add_number; |
| 525 | else if (size != exp.X_add_number) |
| 526 | as_warn (_("size of \"%s\" is already %ld; not changing to %ld"), |
| 527 | name, (long) size, (long) exp.X_add_number); |
| 528 | |
| 529 | *p = c; /* Restore the termination char. */ |
| 530 | |
| 531 | SKIP_WHITESPACE (); |
| 532 | if (*input_line_pointer == ',') |
| 533 | { |
| 534 | align = (unsigned int) parse_align (0); |
| 535 | if (align == (unsigned int) -1) |
| 536 | { |
| 537 | as_warn (_("align value not recognized, using size")); |
| 538 | align = size; |
| 539 | } |
| 540 | if (align > 15) |
| 541 | { |
| 542 | as_warn (_("Alignment (%lu) too large: 15 assumed."), |
| 543 | (unsigned long)align); |
| 544 | align = 15; |
| 545 | } |
| 546 | specified_mask |= SECT_ALGN_SPECIFIED; |
| 547 | } |
| 548 | } |
| 549 | /* else just a section definition. */ |
| 550 | |
| 551 | specified_mask |= SECT_TYPE_SPECIFIED; |
| 552 | new_seg = obj_mach_o_make_or_get_sect (segname, sectname, specified_mask, |
| 553 | BFD_MACH_O_S_ZEROFILL, |
| 554 | BFD_MACH_O_S_ATTR_NONE, |
| 555 | align, (offsetT) 0 /*stub size*/); |
| 556 | if (new_seg == NULL) |
| 557 | return; |
| 558 | |
| 559 | /* In case the user specifies the bss section by mach-o name. |
| 560 | Create it on demand */ |
| 561 | if (strcmp (new_seg->name, BSS_SECTION_NAME) == 0 |
| 562 | && bss_section == NULL) |
| 563 | bss_section = new_seg; |
| 564 | |
| 565 | subseg_set (new_seg, 0); |
| 566 | |
| 567 | if (sym != NULL) |
| 568 | { |
| 569 | char *pfrag; |
| 570 | |
| 571 | if (align) |
| 572 | { |
| 573 | record_alignment (new_seg, align); |
| 574 | frag_align (align, 0, 0); |
| 575 | } |
| 576 | |
| 577 | /* Detach from old frag. */ |
| 578 | if (S_GET_SEGMENT (sym) == new_seg) |
| 579 | symbol_get_frag (sym)->fr_symbol = NULL; |
| 580 | |
| 581 | symbol_set_frag (sym, frag_now); |
| 582 | pfrag = frag_var (rs_org, 1, 1, 0, sym, size, NULL); |
| 583 | *pfrag = 0; |
| 584 | |
| 585 | S_SET_SEGMENT (sym, new_seg); |
| 586 | if (new_seg == bss_section) |
| 587 | S_CLEAR_EXTERNAL (sym); |
| 588 | } |
| 589 | |
| 590 | done: |
| 591 | /* switch back to the section that was current before the .zerofill. */ |
| 592 | subseg_set (old_seg, 0); |
| 593 | } |
| 594 | |
| 595 | static segT |
| 596 | obj_mach_o_segT_from_bfd_name (const char *nam, int must_succeed) |
| 597 | { |
| 598 | const mach_o_section_name_xlat *xlat; |
| 599 | const char *segn; |
| 600 | segT sec; |
| 601 | |
| 602 | /* BFD has tables of flags and default attributes for all the sections that |
| 603 | have a 'canonical' name. */ |
| 604 | xlat = bfd_mach_o_section_data_for_bfd_name (stdoutput, nam, &segn); |
| 605 | if (xlat == NULL) |
| 606 | { |
| 607 | if (must_succeed) |
| 608 | as_fatal (_("BFD is out of sync with GAS, " |
| 609 | "unhandled well-known section type `%s'"), nam); |
| 610 | return NULL; |
| 611 | } |
| 612 | |
| 613 | sec = bfd_get_section_by_name (stdoutput, nam); |
| 614 | if (sec == NULL) |
| 615 | { |
| 616 | bfd_mach_o_section *msect; |
| 617 | |
| 618 | sec = subseg_force_new (xlat->bfd_name, 0); |
| 619 | |
| 620 | /* Set default type, attributes and alignment. */ |
| 621 | msect = bfd_mach_o_get_mach_o_section (sec); |
| 622 | msect->flags = xlat->macho_sectype | xlat->macho_secattr; |
| 623 | msect->align = xlat->sectalign; |
| 624 | |
| 625 | if ((msect->flags & BFD_MACH_O_SECTION_TYPE_MASK) |
| 626 | == BFD_MACH_O_S_ZEROFILL) |
| 627 | seg_info (sec)->bss = 1; |
| 628 | } |
| 629 | |
| 630 | return sec; |
| 631 | } |
| 632 | |
| 633 | static const char * const known_sections[] = |
| 634 | { |
| 635 | /* 0 */ NULL, |
| 636 | /* __TEXT */ |
| 637 | /* 1 */ ".const", |
| 638 | /* 2 */ ".static_const", |
| 639 | /* 3 */ ".cstring", |
| 640 | /* 4 */ ".literal4", |
| 641 | /* 5 */ ".literal8", |
| 642 | /* 6 */ ".literal16", |
| 643 | /* 7 */ ".constructor", |
| 644 | /* 8 */ ".destructor", |
| 645 | /* 9 */ ".eh_frame", |
| 646 | /* __DATA */ |
| 647 | /* 10 */ ".const_data", |
| 648 | /* 11 */ ".static_data", |
| 649 | /* 12 */ ".mod_init_func", |
| 650 | /* 13 */ ".mod_term_func", |
| 651 | /* 14 */ ".dyld", |
| 652 | /* 15 */ ".cfstring" |
| 653 | }; |
| 654 | |
| 655 | /* Interface for a known non-optional section directive. */ |
| 656 | |
| 657 | static void |
| 658 | obj_mach_o_known_section (int sect_index) |
| 659 | { |
| 660 | segT section; |
| 661 | |
| 662 | #ifdef md_flush_pending_output |
| 663 | md_flush_pending_output (); |
| 664 | #endif |
| 665 | |
| 666 | section = obj_mach_o_segT_from_bfd_name (known_sections[sect_index], 1); |
| 667 | if (section != NULL) |
| 668 | subseg_set (section, 0); |
| 669 | |
| 670 | /* else, we leave the section as it was; there was a fatal error anyway. */ |
| 671 | } |
| 672 | |
| 673 | static const char * const objc_sections[] = |
| 674 | { |
| 675 | /* 0 */ NULL, |
| 676 | /* 1 */ ".objc_class", |
| 677 | /* 2 */ ".objc_meta_class", |
| 678 | /* 3 */ ".objc_cat_cls_meth", |
| 679 | /* 4 */ ".objc_cat_inst_meth", |
| 680 | /* 5 */ ".objc_protocol", |
| 681 | /* 6 */ ".objc_string_object", |
| 682 | /* 7 */ ".objc_cls_meth", |
| 683 | /* 8 */ ".objc_inst_meth", |
| 684 | /* 9 */ ".objc_cls_refs", |
| 685 | /* 10 */ ".objc_message_refs", |
| 686 | /* 11 */ ".objc_symbols", |
| 687 | /* 12 */ ".objc_category", |
| 688 | /* 13 */ ".objc_class_vars", |
| 689 | /* 14 */ ".objc_instance_vars", |
| 690 | /* 15 */ ".objc_module_info", |
| 691 | /* 16 */ ".cstring", /* objc_class_names Alias for .cstring */ |
| 692 | /* 17 */ ".cstring", /* Alias objc_meth_var_types for .cstring */ |
| 693 | /* 18 */ ".cstring", /* objc_meth_var_names Alias for .cstring */ |
| 694 | /* 19 */ ".objc_selector_strs", |
| 695 | /* 20 */ ".objc_image_info", /* extension. */ |
| 696 | /* 21 */ ".objc_selector_fixup", /* extension. */ |
| 697 | /* 22 */ ".objc1_class_ext", /* ObjC-1 extension. */ |
| 698 | /* 23 */ ".objc1_property_list", /* ObjC-1 extension. */ |
| 699 | /* 24 */ ".objc1_protocol_ext" /* ObjC-1 extension. */ |
| 700 | }; |
| 701 | |
| 702 | /* This currently does the same as known_sections, but kept separate for |
| 703 | ease of maintenance. */ |
| 704 | |
| 705 | static void |
| 706 | obj_mach_o_objc_section (int sect_index) |
| 707 | { |
| 708 | segT section; |
| 709 | |
| 710 | #ifdef md_flush_pending_output |
| 711 | md_flush_pending_output (); |
| 712 | #endif |
| 713 | |
| 714 | section = obj_mach_o_segT_from_bfd_name (objc_sections[sect_index], 1); |
| 715 | if (section != NULL) |
| 716 | { |
| 717 | obj_mach_o_seen_objc_section = 1; /* We need to ensure that certain |
| 718 | sections are present and in the |
| 719 | right order. */ |
| 720 | subseg_set (section, 0); |
| 721 | } |
| 722 | |
| 723 | /* else, we leave the section as it was; there was a fatal error anyway. */ |
| 724 | } |
| 725 | |
| 726 | /* Debug section directives. */ |
| 727 | |
| 728 | static const char * const debug_sections[] = |
| 729 | { |
| 730 | /* 0 */ NULL, |
| 731 | /* __DWARF */ |
| 732 | /* 1 */ ".debug_frame", |
| 733 | /* 2 */ ".debug_info", |
| 734 | /* 3 */ ".debug_abbrev", |
| 735 | /* 4 */ ".debug_aranges", |
| 736 | /* 5 */ ".debug_macinfo", |
| 737 | /* 6 */ ".debug_line", |
| 738 | /* 7 */ ".debug_loc", |
| 739 | /* 8 */ ".debug_pubnames", |
| 740 | /* 9 */ ".debug_pubtypes", |
| 741 | /* 10 */ ".debug_str", |
| 742 | /* 11 */ ".debug_ranges", |
| 743 | /* 12 */ ".debug_macro" |
| 744 | }; |
| 745 | |
| 746 | /* ??? Maybe these should be conditional on gdwarf-*. |
| 747 | It`s also likely that we will need to be able to set them from the cfi |
| 748 | code. */ |
| 749 | |
| 750 | static void |
| 751 | obj_mach_o_debug_section (int sect_index) |
| 752 | { |
| 753 | segT section; |
| 754 | |
| 755 | #ifdef md_flush_pending_output |
| 756 | md_flush_pending_output (); |
| 757 | #endif |
| 758 | |
| 759 | section = obj_mach_o_segT_from_bfd_name (debug_sections[sect_index], 1); |
| 760 | if (section != NULL) |
| 761 | subseg_set (section, 0); |
| 762 | |
| 763 | /* else, we leave the section as it was; there was a fatal error anyway. */ |
| 764 | } |
| 765 | |
| 766 | /* This could be moved to the tc-xx files, but there is so little dependency |
| 767 | there, that the code might as well be shared. */ |
| 768 | |
| 769 | struct opt_tgt_sect |
| 770 | { |
| 771 | const char *name; |
| 772 | unsigned x86_val; |
| 773 | unsigned ppc_val; |
| 774 | }; |
| 775 | |
| 776 | /* The extensions here are for specific sections that are generated by GCC |
| 777 | and Darwin system tools, but don't have directives in the `system as'. */ |
| 778 | |
| 779 | static const struct opt_tgt_sect tgt_sections[] = |
| 780 | { |
| 781 | /* 0 */ { NULL, 0, 0}, |
| 782 | /* 1 */ { ".lazy_symbol_pointer", 0, 0}, |
| 783 | /* 2 */ { ".lazy_symbol_pointer2", 0, 0}, /* X86 - extension */ |
| 784 | /* 3 */ { ".lazy_symbol_pointer3", 0, 0}, /* X86 - extension */ |
| 785 | /* 4 */ { ".non_lazy_symbol_pointer", 0, 0}, |
| 786 | /* 5 */ { ".non_lazy_symbol_pointer_x86", 0, 0}, /* X86 - extension */ |
| 787 | /* 6 */ { ".symbol_stub", 16, 20}, |
| 788 | /* 7 */ { ".symbol_stub1", 0, 16}, /* PPC - extension */ |
| 789 | /* 8 */ { ".picsymbol_stub", 26, 36}, |
| 790 | /* 9 */ { ".picsymbol_stub1", 0, 32}, /* PPC - extension */ |
| 791 | /* 10 */ { ".picsymbol_stub2", 25, 0}, /* X86 - extension */ |
| 792 | /* 11 */ { ".picsymbol_stub3", 5, 0}, /* X86 - extension */ |
| 793 | }; |
| 794 | |
| 795 | /* Interface for an optional section directive. */ |
| 796 | |
| 797 | static void |
| 798 | obj_mach_o_opt_tgt_section (int sect_index) |
| 799 | { |
| 800 | const struct opt_tgt_sect *tgtsct = &tgt_sections[sect_index]; |
| 801 | segT section; |
| 802 | |
| 803 | #ifdef md_flush_pending_output |
| 804 | md_flush_pending_output (); |
| 805 | #endif |
| 806 | |
| 807 | section = obj_mach_o_segT_from_bfd_name (tgtsct->name, 0); |
| 808 | if (section == NULL) |
| 809 | { |
| 810 | as_bad (_("%s is not used for the selected target"), tgtsct->name); |
| 811 | /* Leave the section as it is. */ |
| 812 | } |
| 813 | else |
| 814 | { |
| 815 | bfd_mach_o_section *mo_sec = bfd_mach_o_get_mach_o_section (section); |
| 816 | subseg_set (section, 0); |
| 817 | #if defined (TC_I386) |
| 818 | mo_sec->reserved2 = tgtsct->x86_val; |
| 819 | #elif defined (TC_PPC) |
| 820 | mo_sec->reserved2 = tgtsct->ppc_val; |
| 821 | #else |
| 822 | mo_sec->reserved2 = 0; |
| 823 | #endif |
| 824 | } |
| 825 | } |
| 826 | |
| 827 | /* We don't necessarily have the three 'base' sections on mach-o. |
| 828 | Normally, we would start up with only the 'text' section defined. |
| 829 | However, even that can be suppressed with (TODO) c/l option "-n". |
| 830 | Thus, we have to be able to create all three sections on-demand. */ |
| 831 | |
| 832 | static void |
| 833 | obj_mach_o_base_section (int sect_index) |
| 834 | { |
| 835 | segT section; |
| 836 | |
| 837 | #ifdef md_flush_pending_output |
| 838 | md_flush_pending_output (); |
| 839 | #endif |
| 840 | |
| 841 | /* We don't support numeric (or any other) qualifications on the |
| 842 | well-known section shorthands. */ |
| 843 | demand_empty_rest_of_line (); |
| 844 | |
| 845 | switch (sect_index) |
| 846 | { |
| 847 | /* Handle the three sections that are globally known within GAS. |
| 848 | For Mach-O, these are created on demand rather than at startup. */ |
| 849 | case 1: |
| 850 | if (text_section == NULL) |
| 851 | text_section = obj_mach_o_segT_from_bfd_name (TEXT_SECTION_NAME, 1); |
| 852 | if (obj_mach_o_is_static) |
| 853 | { |
| 854 | bfd_mach_o_section *mo_sec |
| 855 | = bfd_mach_o_get_mach_o_section (text_section); |
| 856 | mo_sec->flags &= ~BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS; |
| 857 | } |
| 858 | section = text_section; |
| 859 | break; |
| 860 | case 2: |
| 861 | if (data_section == NULL) |
| 862 | data_section = obj_mach_o_segT_from_bfd_name (DATA_SECTION_NAME, 1); |
| 863 | section = data_section; |
| 864 | break; |
| 865 | case 3: |
| 866 | /* ??? maybe this achieves very little, as an addition. */ |
| 867 | if (bss_section == NULL) |
| 868 | { |
| 869 | bss_section = obj_mach_o_segT_from_bfd_name (BSS_SECTION_NAME, 1); |
| 870 | seg_info (bss_section)->bss = 1; |
| 871 | } |
| 872 | section = bss_section; |
| 873 | break; |
| 874 | default: |
| 875 | as_fatal (_("internal error: base section index out of range")); |
| 876 | return; |
| 877 | break; |
| 878 | } |
| 879 | subseg_set (section, 0); |
| 880 | } |
| 881 | |
| 882 | /* This finishes off parsing a .comm or .lcomm statement, which both can have |
| 883 | an (optional) alignment field. It also allows us to create the bss section |
| 884 | on demand. */ |
| 885 | |
| 886 | static symbolS * |
| 887 | obj_mach_o_common_parse (int is_local, symbolS *symbolP, |
| 888 | addressT size) |
| 889 | { |
| 890 | addressT align = 0; |
| 891 | bfd_mach_o_asymbol *s; |
| 892 | |
| 893 | SKIP_WHITESPACE (); |
| 894 | |
| 895 | /* Both comm and lcomm take an optional alignment, as a power |
| 896 | of two between 1 and 15. */ |
| 897 | if (*input_line_pointer == ',') |
| 898 | { |
| 899 | /* We expect a power of 2. */ |
| 900 | align = parse_align (0); |
| 901 | if (align == (addressT) -1) |
| 902 | return NULL; |
| 903 | if (align > 15) |
| 904 | { |
| 905 | as_warn (_("Alignment (%lu) too large: 15 assumed."), |
| 906 | (unsigned long)align); |
| 907 | align = 15; |
| 908 | } |
| 909 | } |
| 910 | |
| 911 | s = (bfd_mach_o_asymbol *) symbol_get_bfdsym (symbolP); |
| 912 | if (is_local) |
| 913 | { |
| 914 | /* Create the BSS section on demand. */ |
| 915 | if (bss_section == NULL) |
| 916 | { |
| 917 | bss_section = obj_mach_o_segT_from_bfd_name (BSS_SECTION_NAME, 1); |
| 918 | seg_info (bss_section)->bss = 1; |
| 919 | } |
| 920 | bss_alloc (symbolP, size, align); |
| 921 | s->n_type = BFD_MACH_O_N_SECT; |
| 922 | S_CLEAR_EXTERNAL (symbolP); |
| 923 | } |
| 924 | else |
| 925 | { |
| 926 | S_SET_VALUE (symbolP, size); |
| 927 | S_SET_ALIGN (symbolP, align); |
| 928 | S_SET_EXTERNAL (symbolP); |
| 929 | S_SET_SEGMENT (symbolP, bfd_com_section_ptr); |
| 930 | s->n_type = BFD_MACH_O_N_UNDF | BFD_MACH_O_N_EXT; |
| 931 | } |
| 932 | |
| 933 | /* This is a data object (whatever we choose that to mean). */ |
| 934 | s->symbol.flags |= BSF_OBJECT; |
| 935 | |
| 936 | /* We've set symbol qualifiers, so validate if you can. */ |
| 937 | s->symbol.udata.i = SYM_MACHO_FIELDS_NOT_VALIDATED; |
| 938 | |
| 939 | return symbolP; |
| 940 | } |
| 941 | |
| 942 | static void |
| 943 | obj_mach_o_comm (int is_local) |
| 944 | { |
| 945 | s_comm_internal (is_local, obj_mach_o_common_parse); |
| 946 | } |
| 947 | |
| 948 | /* Set properties that apply to the whole file. At present, the only |
| 949 | one defined, is subsections_via_symbols. */ |
| 950 | |
| 951 | typedef enum obj_mach_o_file_properties { |
| 952 | OBJ_MACH_O_FILE_PROP_NONE = 0, |
| 953 | OBJ_MACH_O_FILE_PROP_SUBSECTS_VIA_SYMS, |
| 954 | OBJ_MACH_O_FILE_PROP_MAX |
| 955 | } obj_mach_o_file_properties; |
| 956 | |
| 957 | static void |
| 958 | obj_mach_o_fileprop (int prop) |
| 959 | { |
| 960 | if (prop < 0 || prop >= OBJ_MACH_O_FILE_PROP_MAX) |
| 961 | as_fatal (_("internal error: bad file property ID %d"), prop); |
| 962 | |
| 963 | switch ((obj_mach_o_file_properties) prop) |
| 964 | { |
| 965 | case OBJ_MACH_O_FILE_PROP_SUBSECTS_VIA_SYMS: |
| 966 | obj_mach_o_subsections_by_symbols = 1; |
| 967 | if (!bfd_set_private_flags (stdoutput, |
| 968 | BFD_MACH_O_MH_SUBSECTIONS_VIA_SYMBOLS)) |
| 969 | as_bad (_("failed to set subsections by symbols")); |
| 970 | demand_empty_rest_of_line (); |
| 971 | break; |
| 972 | default: |
| 973 | break; |
| 974 | } |
| 975 | } |
| 976 | |
| 977 | /* Temporary markers for symbol reference data. |
| 978 | Lazy will remain in place. */ |
| 979 | #define LAZY 0x01 |
| 980 | #define REFE 0x02 |
| 981 | |
| 982 | /* We have a bunch of qualifiers that may be applied to symbols. |
| 983 | .globl is handled here so that we might make sure that conflicting qualifiers |
| 984 | are caught where possible. */ |
| 985 | |
| 986 | typedef enum obj_mach_o_symbol_type { |
| 987 | OBJ_MACH_O_SYM_UNK = 0, |
| 988 | OBJ_MACH_O_SYM_LOCAL = 1, |
| 989 | OBJ_MACH_O_SYM_GLOBL = 2, |
| 990 | OBJ_MACH_O_SYM_REFERENCE = 3, |
| 991 | OBJ_MACH_O_SYM_WEAK_REF = 4, |
| 992 | OBJ_MACH_O_SYM_LAZY_REF = 5, |
| 993 | OBJ_MACH_O_SYM_WEAK_DEF = 6, |
| 994 | OBJ_MACH_O_SYM_PRIV_EXT = 7, |
| 995 | OBJ_MACH_O_SYM_NO_DEAD_STRIP = 8, |
| 996 | OBJ_MACH_O_SYM_WEAK = 9 |
| 997 | } obj_mach_o_symbol_type; |
| 998 | |
| 999 | /* Set Mach-O-specific symbol qualifiers. */ |
| 1000 | |
| 1001 | static int |
| 1002 | obj_mach_o_set_symbol_qualifier (symbolS *sym, int type) |
| 1003 | { |
| 1004 | int is_defined; |
| 1005 | bfd_mach_o_asymbol *s = (bfd_mach_o_asymbol *) symbol_get_bfdsym (sym); |
| 1006 | bfd_mach_o_section *sec; |
| 1007 | int sectype = -1; |
| 1008 | |
| 1009 | /* If the symbol is defined, then we can do more rigorous checking on |
| 1010 | the validity of the qualifiers. Otherwise, we are stuck with waiting |
| 1011 | until it's defined - or until write the file. |
| 1012 | |
| 1013 | In certain cases (e.g. when a symbol qualifier is intended to introduce |
| 1014 | an undefined symbol in a stubs section) we should check that the current |
| 1015 | section is appropriate to the qualifier. */ |
| 1016 | |
| 1017 | is_defined = s->symbol.section != bfd_und_section_ptr; |
| 1018 | if (is_defined) |
| 1019 | sec = bfd_mach_o_get_mach_o_section (s->symbol.section) ; |
| 1020 | else |
| 1021 | sec = bfd_mach_o_get_mach_o_section (now_seg) ; |
| 1022 | |
| 1023 | if (sec != NULL) |
| 1024 | sectype = sec->flags & BFD_MACH_O_SECTION_TYPE_MASK; |
| 1025 | |
| 1026 | switch ((obj_mach_o_symbol_type) type) |
| 1027 | { |
| 1028 | case OBJ_MACH_O_SYM_LOCAL: |
| 1029 | /* This is an extension over the system tools. */ |
| 1030 | if (s->n_type & (BFD_MACH_O_N_PEXT | BFD_MACH_O_N_EXT)) |
| 1031 | { |
| 1032 | as_bad (_("'%s' previously declared as '%s'."), s->symbol.name, |
| 1033 | (s->n_type & BFD_MACH_O_N_PEXT) ? "private extern" |
| 1034 | : "global" ); |
| 1035 | s->symbol.udata.i = SYM_MACHO_FIELDS_UNSET; |
| 1036 | return 1; |
| 1037 | } |
| 1038 | else |
| 1039 | { |
| 1040 | s->n_type &= ~BFD_MACH_O_N_EXT; |
| 1041 | S_CLEAR_EXTERNAL (sym); |
| 1042 | } |
| 1043 | break; |
| 1044 | |
| 1045 | case OBJ_MACH_O_SYM_PRIV_EXT: |
| 1046 | s->n_type |= BFD_MACH_O_N_PEXT ; |
| 1047 | s->n_desc &= ~LAZY; /* The native tool switches this off too. */ |
| 1048 | /* We follow the system tools in marking PEXT as also global. */ |
| 1049 | /* Fall through. */ |
| 1050 | |
| 1051 | case OBJ_MACH_O_SYM_GLOBL: |
| 1052 | /* It's not an error to define a symbol and then make it global. */ |
| 1053 | s->n_type |= BFD_MACH_O_N_EXT; |
| 1054 | S_SET_EXTERNAL (sym); |
| 1055 | break; |
| 1056 | |
| 1057 | case OBJ_MACH_O_SYM_REFERENCE: |
| 1058 | if (is_defined) |
| 1059 | s->n_desc |= BFD_MACH_O_N_NO_DEAD_STRIP; |
| 1060 | else |
| 1061 | s->n_desc |= (REFE | BFD_MACH_O_N_NO_DEAD_STRIP); |
| 1062 | break; |
| 1063 | |
| 1064 | case OBJ_MACH_O_SYM_LAZY_REF: |
| 1065 | if (is_defined) |
| 1066 | s->n_desc |= BFD_MACH_O_N_NO_DEAD_STRIP; |
| 1067 | else |
| 1068 | s->n_desc |= (REFE | LAZY | BFD_MACH_O_N_NO_DEAD_STRIP); |
| 1069 | break; |
| 1070 | |
| 1071 | /* Force ld to retain the symbol - even if it appears unused. */ |
| 1072 | case OBJ_MACH_O_SYM_NO_DEAD_STRIP: |
| 1073 | s->n_desc |= BFD_MACH_O_N_NO_DEAD_STRIP ; |
| 1074 | break; |
| 1075 | |
| 1076 | /* Mach-O's idea of weak ... */ |
| 1077 | case OBJ_MACH_O_SYM_WEAK_REF: |
| 1078 | s->n_desc |= BFD_MACH_O_N_WEAK_REF ; |
| 1079 | break; |
| 1080 | |
| 1081 | case OBJ_MACH_O_SYM_WEAK_DEF: |
| 1082 | if (is_defined && sectype != BFD_MACH_O_S_COALESCED) |
| 1083 | { |
| 1084 | as_bad (_("'%s' can't be a weak_definition (currently only" |
| 1085 | " supported in sections of type coalesced)"), |
| 1086 | s->symbol.name); |
| 1087 | s->symbol.udata.i = SYM_MACHO_FIELDS_UNSET; |
| 1088 | return 1; |
| 1089 | } |
| 1090 | else |
| 1091 | s->n_desc |= BFD_MACH_O_N_WEAK_DEF; |
| 1092 | break; |
| 1093 | |
| 1094 | case OBJ_MACH_O_SYM_WEAK: |
| 1095 | /* A generic 'weak' - we try to figure out what it means at |
| 1096 | symbol frob time. */ |
| 1097 | S_SET_WEAK (sym); |
| 1098 | break; |
| 1099 | |
| 1100 | default: |
| 1101 | break; |
| 1102 | } |
| 1103 | |
| 1104 | /* We've seen some kind of qualifier - check validity if or when the entity |
| 1105 | is defined. */ |
| 1106 | s->symbol.udata.i = SYM_MACHO_FIELDS_NOT_VALIDATED; |
| 1107 | return 0; |
| 1108 | } |
| 1109 | |
| 1110 | /* Respond to symbol qualifiers. |
| 1111 | All of the form: |
| 1112 | .<qualifier> symbol [, symbol]* |
| 1113 | a list of symbols is an extension over the Darwin system as. */ |
| 1114 | |
| 1115 | static void |
| 1116 | obj_mach_o_sym_qual (int ntype) |
| 1117 | { |
| 1118 | char *name; |
| 1119 | char c; |
| 1120 | symbolS *symbolP; |
| 1121 | |
| 1122 | #ifdef md_flush_pending_output |
| 1123 | md_flush_pending_output (); |
| 1124 | #endif |
| 1125 | |
| 1126 | do |
| 1127 | { |
| 1128 | c = get_symbol_name (&name); |
| 1129 | symbolP = symbol_find_or_make (name); |
| 1130 | obj_mach_o_set_symbol_qualifier (symbolP, ntype); |
| 1131 | *input_line_pointer = c; |
| 1132 | SKIP_WHITESPACE_AFTER_NAME (); |
| 1133 | c = *input_line_pointer; |
| 1134 | if (c == ',') |
| 1135 | { |
| 1136 | input_line_pointer++; |
| 1137 | SKIP_WHITESPACE (); |
| 1138 | if (is_end_of_line[(unsigned char) *input_line_pointer]) |
| 1139 | c = '\n'; |
| 1140 | } |
| 1141 | } |
| 1142 | while (c == ','); |
| 1143 | |
| 1144 | demand_empty_rest_of_line (); |
| 1145 | } |
| 1146 | |
| 1147 | typedef struct obj_mach_o_indirect_sym |
| 1148 | { |
| 1149 | symbolS *sym; |
| 1150 | segT sect; |
| 1151 | struct obj_mach_o_indirect_sym *next; |
| 1152 | } obj_mach_o_indirect_sym; |
| 1153 | |
| 1154 | /* We store in order an maintain a pointer to the last one - to save reversing |
| 1155 | later. */ |
| 1156 | obj_mach_o_indirect_sym *indirect_syms; |
| 1157 | obj_mach_o_indirect_sym *indirect_syms_tail; |
| 1158 | |
| 1159 | static void |
| 1160 | obj_mach_o_indirect_symbol (int arg ATTRIBUTE_UNUSED) |
| 1161 | { |
| 1162 | bfd_mach_o_section *sec = bfd_mach_o_get_mach_o_section (now_seg); |
| 1163 | |
| 1164 | #ifdef md_flush_pending_output |
| 1165 | md_flush_pending_output (); |
| 1166 | #endif |
| 1167 | |
| 1168 | if (obj_mach_o_is_static) |
| 1169 | as_bad (_("use of .indirect_symbols requires `-dynamic'")); |
| 1170 | |
| 1171 | switch (sec->flags & BFD_MACH_O_SECTION_TYPE_MASK) |
| 1172 | { |
| 1173 | case BFD_MACH_O_S_SYMBOL_STUBS: |
| 1174 | case BFD_MACH_O_S_LAZY_SYMBOL_POINTERS: |
| 1175 | case BFD_MACH_O_S_NON_LAZY_SYMBOL_POINTERS: |
| 1176 | { |
| 1177 | obj_mach_o_indirect_sym *isym; |
| 1178 | char *name; |
| 1179 | char c = get_symbol_name (&name); |
| 1180 | symbolS *sym = symbol_find_or_make (name); |
| 1181 | unsigned int elsize = |
| 1182 | bfd_mach_o_section_get_entry_size (stdoutput, sec); |
| 1183 | |
| 1184 | if (elsize == 0) |
| 1185 | { |
| 1186 | as_bad (_("attempt to add an indirect_symbol to a stub or" |
| 1187 | " reference section with a zero-sized element at %s"), |
| 1188 | name); |
| 1189 | (void) restore_line_pointer (c); |
| 1190 | ignore_rest_of_line (); |
| 1191 | return; |
| 1192 | } |
| 1193 | (void) restore_line_pointer (c); |
| 1194 | |
| 1195 | /* The indirect symbols are validated after the symbol table is |
| 1196 | frozen, we must make sure that if a local symbol is used as an |
| 1197 | indirect, it is promoted to a 'real' one. Fetching the bfd sym |
| 1198 | achieves this. */ |
| 1199 | symbol_get_bfdsym (sym); |
| 1200 | isym = XNEW (obj_mach_o_indirect_sym); |
| 1201 | |
| 1202 | /* Just record the data for now, we will validate it when we |
| 1203 | compute the output in obj_mach_o_set_indirect_symbols. */ |
| 1204 | isym->sym = sym; |
| 1205 | isym->sect = now_seg; |
| 1206 | isym->next = NULL; |
| 1207 | if (indirect_syms == NULL) |
| 1208 | indirect_syms = isym; |
| 1209 | else |
| 1210 | indirect_syms_tail->next = isym; |
| 1211 | indirect_syms_tail = isym; |
| 1212 | } |
| 1213 | break; |
| 1214 | |
| 1215 | default: |
| 1216 | as_bad (_("an .indirect_symbol must be in a symbol pointer" |
| 1217 | " or stub section.")); |
| 1218 | ignore_rest_of_line (); |
| 1219 | return; |
| 1220 | } |
| 1221 | demand_empty_rest_of_line (); |
| 1222 | } |
| 1223 | |
| 1224 | const pseudo_typeS mach_o_pseudo_table[] = |
| 1225 | { |
| 1226 | /* Section directives. */ |
| 1227 | { "comm", obj_mach_o_comm, 0 }, |
| 1228 | { "lcomm", obj_mach_o_comm, 1 }, |
| 1229 | |
| 1230 | { "text", obj_mach_o_base_section, 1}, |
| 1231 | { "data", obj_mach_o_base_section, 2}, |
| 1232 | { "bss", obj_mach_o_base_section, 3}, /* extension */ |
| 1233 | |
| 1234 | { "const", obj_mach_o_known_section, 1}, |
| 1235 | { "static_const", obj_mach_o_known_section, 2}, |
| 1236 | { "cstring", obj_mach_o_known_section, 3}, |
| 1237 | { "literal4", obj_mach_o_known_section, 4}, |
| 1238 | { "literal8", obj_mach_o_known_section, 5}, |
| 1239 | { "literal16", obj_mach_o_known_section, 6}, |
| 1240 | { "constructor", obj_mach_o_known_section, 7}, |
| 1241 | { "destructor", obj_mach_o_known_section, 8}, |
| 1242 | { "eh_frame", obj_mach_o_known_section, 9}, |
| 1243 | |
| 1244 | { "const_data", obj_mach_o_known_section, 10}, |
| 1245 | { "static_data", obj_mach_o_known_section, 11}, |
| 1246 | { "mod_init_func", obj_mach_o_known_section, 12}, |
| 1247 | { "mod_term_func", obj_mach_o_known_section, 13}, |
| 1248 | { "dyld", obj_mach_o_known_section, 14}, |
| 1249 | { "cfstring", obj_mach_o_known_section, 15}, |
| 1250 | |
| 1251 | { "objc_class", obj_mach_o_objc_section, 1}, |
| 1252 | { "objc_meta_class", obj_mach_o_objc_section, 2}, |
| 1253 | { "objc_cat_cls_meth", obj_mach_o_objc_section, 3}, |
| 1254 | { "objc_cat_inst_meth", obj_mach_o_objc_section, 4}, |
| 1255 | { "objc_protocol", obj_mach_o_objc_section, 5}, |
| 1256 | { "objc_string_object", obj_mach_o_objc_section, 6}, |
| 1257 | { "objc_cls_meth", obj_mach_o_objc_section, 7}, |
| 1258 | { "objc_inst_meth", obj_mach_o_objc_section, 8}, |
| 1259 | { "objc_cls_refs", obj_mach_o_objc_section, 9}, |
| 1260 | { "objc_message_refs", obj_mach_o_objc_section, 10}, |
| 1261 | { "objc_symbols", obj_mach_o_objc_section, 11}, |
| 1262 | { "objc_category", obj_mach_o_objc_section, 12}, |
| 1263 | { "objc_class_vars", obj_mach_o_objc_section, 13}, |
| 1264 | { "objc_instance_vars", obj_mach_o_objc_section, 14}, |
| 1265 | { "objc_module_info", obj_mach_o_objc_section, 15}, |
| 1266 | { "objc_class_names", obj_mach_o_objc_section, 16}, /* Alias for .cstring */ |
| 1267 | { "objc_meth_var_types", obj_mach_o_objc_section, 17}, /* Alias for .cstring */ |
| 1268 | { "objc_meth_var_names", obj_mach_o_objc_section, 18}, /* Alias for .cstring */ |
| 1269 | { "objc_selector_strs", obj_mach_o_objc_section, 19}, |
| 1270 | { "objc_image_info", obj_mach_o_objc_section, 20}, /* extension. */ |
| 1271 | { "objc_selector_fixup", obj_mach_o_objc_section, 21}, /* extension. */ |
| 1272 | { "objc1_class_ext", obj_mach_o_objc_section, 22}, /* ObjC-1 extension. */ |
| 1273 | { "objc1_property_list", obj_mach_o_objc_section, 23}, /* ObjC-1 extension. */ |
| 1274 | { "objc1_protocol_ext", obj_mach_o_objc_section, 24}, /* ObjC-1 extension. */ |
| 1275 | |
| 1276 | { "debug_frame", obj_mach_o_debug_section, 1}, /* extension. */ |
| 1277 | { "debug_info", obj_mach_o_debug_section, 2}, /* extension. */ |
| 1278 | { "debug_abbrev", obj_mach_o_debug_section, 3}, /* extension. */ |
| 1279 | { "debug_aranges", obj_mach_o_debug_section, 4}, /* extension. */ |
| 1280 | { "debug_macinfo", obj_mach_o_debug_section, 5}, /* extension. */ |
| 1281 | { "debug_line", obj_mach_o_debug_section, 6}, /* extension. */ |
| 1282 | { "debug_loc", obj_mach_o_debug_section, 7}, /* extension. */ |
| 1283 | { "debug_pubnames", obj_mach_o_debug_section, 8}, /* extension. */ |
| 1284 | { "debug_pubtypes", obj_mach_o_debug_section, 9}, /* extension. */ |
| 1285 | { "debug_str", obj_mach_o_debug_section, 10}, /* extension. */ |
| 1286 | { "debug_ranges", obj_mach_o_debug_section, 11}, /* extension. */ |
| 1287 | { "debug_macro", obj_mach_o_debug_section, 12}, /* extension. */ |
| 1288 | |
| 1289 | { "lazy_symbol_pointer", obj_mach_o_opt_tgt_section, 1}, |
| 1290 | { "lazy_symbol_pointer2", obj_mach_o_opt_tgt_section, 2}, /* extension. */ |
| 1291 | { "lazy_symbol_pointer3", obj_mach_o_opt_tgt_section, 3}, /* extension. */ |
| 1292 | { "non_lazy_symbol_pointer", obj_mach_o_opt_tgt_section, 4}, |
| 1293 | { "non_lazy_symbol_pointer_x86", obj_mach_o_opt_tgt_section, 5}, /* extension. */ |
| 1294 | { "symbol_stub", obj_mach_o_opt_tgt_section, 6}, |
| 1295 | { "symbol_stub1", obj_mach_o_opt_tgt_section, 7}, /* extension. */ |
| 1296 | { "picsymbol_stub", obj_mach_o_opt_tgt_section, 8}, /* extension. */ |
| 1297 | { "picsymbol_stub1", obj_mach_o_opt_tgt_section, 9}, /* extension. */ |
| 1298 | { "picsymbol_stub2", obj_mach_o_opt_tgt_section, 4}, /* extension. */ |
| 1299 | { "picsymbol_stub3", obj_mach_o_opt_tgt_section, 4}, /* extension. */ |
| 1300 | |
| 1301 | { "section", obj_mach_o_section, 0}, |
| 1302 | { "zerofill", obj_mach_o_zerofill, 0}, |
| 1303 | |
| 1304 | /* Symbol qualifiers. */ |
| 1305 | {"local", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_LOCAL}, |
| 1306 | {"globl", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_GLOBL}, |
| 1307 | {"reference", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_REFERENCE}, |
| 1308 | {"weak_reference", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_WEAK_REF}, |
| 1309 | {"lazy_reference", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_LAZY_REF}, |
| 1310 | {"weak_definition", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_WEAK_DEF}, |
| 1311 | {"private_extern", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_PRIV_EXT}, |
| 1312 | {"no_dead_strip", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_NO_DEAD_STRIP}, |
| 1313 | {"weak", obj_mach_o_sym_qual, OBJ_MACH_O_SYM_WEAK}, /* ext */ |
| 1314 | |
| 1315 | { "indirect_symbol", obj_mach_o_indirect_symbol, 0}, |
| 1316 | |
| 1317 | /* File flags. */ |
| 1318 | { "subsections_via_symbols", obj_mach_o_fileprop, |
| 1319 | OBJ_MACH_O_FILE_PROP_SUBSECTS_VIA_SYMS}, |
| 1320 | |
| 1321 | {NULL, NULL, 0} |
| 1322 | }; |
| 1323 | |
| 1324 | /* Determine the default n_type value for a symbol from its section. */ |
| 1325 | |
| 1326 | static unsigned |
| 1327 | obj_mach_o_type_for_symbol (bfd_mach_o_asymbol *s) |
| 1328 | { |
| 1329 | if (s->symbol.section == bfd_abs_section_ptr) |
| 1330 | return BFD_MACH_O_N_ABS; |
| 1331 | else if (s->symbol.section == bfd_com_section_ptr |
| 1332 | || s->symbol.section == bfd_und_section_ptr) |
| 1333 | return BFD_MACH_O_N_UNDF; |
| 1334 | else |
| 1335 | return BFD_MACH_O_N_SECT; |
| 1336 | } |
| 1337 | |
| 1338 | void |
| 1339 | obj_mach_o_frob_colon (const char *name) |
| 1340 | { |
| 1341 | if (!bfd_is_local_label_name (stdoutput, name)) |
| 1342 | { |
| 1343 | /* A non-local label will create a new subsection, so start a new |
| 1344 | frag. */ |
| 1345 | frag_wane (frag_now); |
| 1346 | frag_new (0); |
| 1347 | } |
| 1348 | } |
| 1349 | |
| 1350 | /* We need to check the correspondence between some kinds of symbols and their |
| 1351 | sections. Common and BSS vars will seen via the obj_macho_comm() function. |
| 1352 | |
| 1353 | The earlier we can pick up a problem, the better the diagnostics will be. |
| 1354 | |
| 1355 | However, when symbol type information is attached, the symbol section will |
| 1356 | quite possibly be unknown. So we are stuck with checking (most of the) |
| 1357 | validity at the time the file is written (unfortunately, then one doesn't |
| 1358 | get line number information in the diagnostic). */ |
| 1359 | |
| 1360 | /* Here we pick up the case where symbol qualifiers have been applied that |
| 1361 | are possibly incompatible with the section etc. that the symbol is defined |
| 1362 | in. */ |
| 1363 | |
| 1364 | void obj_mach_o_frob_label (struct symbol *sp) |
| 1365 | { |
| 1366 | bfd_mach_o_asymbol *s; |
| 1367 | unsigned base_type; |
| 1368 | bfd_mach_o_section *sec; |
| 1369 | int sectype = -1; |
| 1370 | |
| 1371 | if (!bfd_is_local_label_name (stdoutput, S_GET_NAME (sp))) |
| 1372 | { |
| 1373 | /* If this is a non-local label, it should have started a new sub- |
| 1374 | section. */ |
| 1375 | gas_assert (frag_now->obj_frag_data.subsection == NULL); |
| 1376 | frag_now->obj_frag_data.subsection = sp; |
| 1377 | } |
| 1378 | |
| 1379 | /* Leave local symbols alone. */ |
| 1380 | |
| 1381 | if (S_IS_LOCAL (sp)) |
| 1382 | return; |
| 1383 | |
| 1384 | s = (bfd_mach_o_asymbol *) symbol_get_bfdsym (sp); |
| 1385 | /* Leave debug symbols alone. */ |
| 1386 | if ((s->n_type & BFD_MACH_O_N_STAB) != 0) |
| 1387 | return; |
| 1388 | |
| 1389 | /* This is the base symbol type, that we mask in. */ |
| 1390 | base_type = obj_mach_o_type_for_symbol (s); |
| 1391 | |
| 1392 | sec = bfd_mach_o_get_mach_o_section (s->symbol.section); |
| 1393 | if (sec != NULL) |
| 1394 | sectype = sec->flags & BFD_MACH_O_SECTION_TYPE_MASK; |
| 1395 | |
| 1396 | /* If there is a pre-existing qualifier, we can make some checks about |
| 1397 | validity now. */ |
| 1398 | |
| 1399 | if(s->symbol.udata.i == SYM_MACHO_FIELDS_NOT_VALIDATED) |
| 1400 | { |
| 1401 | if ((s->n_desc & BFD_MACH_O_N_WEAK_DEF) |
| 1402 | && sectype != BFD_MACH_O_S_COALESCED) |
| 1403 | { |
| 1404 | as_bad (_("'%s' can't be a weak_definition (currently only supported" |
| 1405 | " in sections of type coalesced)"), s->symbol.name); |
| 1406 | /* Don't cascade errors. */ |
| 1407 | s->symbol.udata.i = SYM_MACHO_FIELDS_UNSET; |
| 1408 | } |
| 1409 | |
| 1410 | /* Have we changed from an undefined to defined ref? */ |
| 1411 | s->n_desc &= ~(REFE | LAZY); |
| 1412 | } |
| 1413 | |
| 1414 | s->n_type &= ~BFD_MACH_O_N_TYPE; |
| 1415 | s->n_type |= base_type; |
| 1416 | } |
| 1417 | |
| 1418 | /* This is the fall-back, we come here when we get to the end of the file and |
| 1419 | the symbol is not defined - or there are combinations of qualifiers required |
| 1420 | (e.g. global + weak_def). */ |
| 1421 | |
| 1422 | int |
| 1423 | obj_mach_o_frob_symbol (struct symbol *sp) |
| 1424 | { |
| 1425 | bfd_mach_o_asymbol *s; |
| 1426 | unsigned base_type; |
| 1427 | bfd_mach_o_section *sec; |
| 1428 | int sectype = -1; |
| 1429 | |
| 1430 | /* Leave local symbols alone. */ |
| 1431 | if (S_IS_LOCAL (sp)) |
| 1432 | return 0; |
| 1433 | |
| 1434 | s = (bfd_mach_o_asymbol *) symbol_get_bfdsym (sp); |
| 1435 | /* Leave debug symbols alone. */ |
| 1436 | if ((s->n_type & BFD_MACH_O_N_STAB) != 0) |
| 1437 | return 0; |
| 1438 | |
| 1439 | base_type = obj_mach_o_type_for_symbol (s); |
| 1440 | sec = bfd_mach_o_get_mach_o_section (s->symbol.section); |
| 1441 | if (sec != NULL) |
| 1442 | sectype = sec->flags & BFD_MACH_O_SECTION_TYPE_MASK; |
| 1443 | |
| 1444 | if (s->symbol.section == bfd_und_section_ptr) |
| 1445 | { |
| 1446 | /* ??? Do we really gain much from implementing this as well as the |
| 1447 | mach-o specific ones? */ |
| 1448 | if (s->symbol.flags & BSF_WEAK) |
| 1449 | s->n_desc |= BFD_MACH_O_N_WEAK_REF; |
| 1450 | |
| 1451 | /* Undefined syms, become extern. */ |
| 1452 | s->n_type |= BFD_MACH_O_N_EXT; |
| 1453 | S_SET_EXTERNAL (sp); |
| 1454 | } |
| 1455 | else if (s->symbol.section == bfd_com_section_ptr) |
| 1456 | { |
| 1457 | /* ... so do comm. */ |
| 1458 | s->n_type |= BFD_MACH_O_N_EXT; |
| 1459 | S_SET_EXTERNAL (sp); |
| 1460 | } |
| 1461 | else |
| 1462 | { |
| 1463 | if ((s->symbol.flags & BSF_WEAK) |
| 1464 | && (sectype == BFD_MACH_O_S_COALESCED) |
| 1465 | && (s->n_type & (BFD_MACH_O_N_PEXT | BFD_MACH_O_N_EXT))) |
| 1466 | s->n_desc |= BFD_MACH_O_N_WEAK_DEF; |
| 1467 | /* ??? we should do this - but then that reveals that the semantics of weak |
| 1468 | are different from what's supported in mach-o object files. |
| 1469 | else |
| 1470 | as_bad (_("'%s' can't be a weak_definition."), |
| 1471 | s->symbol.name); */ |
| 1472 | } |
| 1473 | |
| 1474 | if (s->symbol.udata.i == SYM_MACHO_FIELDS_UNSET) |
| 1475 | { |
| 1476 | /* Anything here that should be added that is non-standard. */ |
| 1477 | s->n_desc &= ~BFD_MACH_O_REFERENCE_MASK; |
| 1478 | } |
| 1479 | else if (s->symbol.udata.i == SYM_MACHO_FIELDS_NOT_VALIDATED) |
| 1480 | { |
| 1481 | /* Try to validate any combinations. */ |
| 1482 | if (s->n_desc & BFD_MACH_O_N_WEAK_DEF) |
| 1483 | { |
| 1484 | if (s->symbol.section == bfd_und_section_ptr) |
| 1485 | as_bad (_("'%s' can't be a weak_definition (since it is" |
| 1486 | " undefined)"), s->symbol.name); |
| 1487 | else if (sectype != BFD_MACH_O_S_COALESCED) |
| 1488 | as_bad (_("'%s' can't be a weak_definition (currently only supported" |
| 1489 | " in sections of type coalesced)"), s->symbol.name); |
| 1490 | else if (! (s->n_type & (BFD_MACH_O_N_PEXT | BFD_MACH_O_N_EXT))) |
| 1491 | as_bad (_("Non-global symbol: '%s' can't be a weak_definition."), |
| 1492 | s->symbol.name); |
| 1493 | } |
| 1494 | |
| 1495 | } |
| 1496 | else |
| 1497 | as_bad (_("internal error: [%s] unexpected code [%lx] in frob symbol"), |
| 1498 | s->symbol.name, (unsigned long)s->symbol.udata.i); |
| 1499 | |
| 1500 | s->n_type &= ~BFD_MACH_O_N_TYPE; |
| 1501 | s->n_type |= base_type; |
| 1502 | |
| 1503 | if (s->symbol.flags & BSF_GLOBAL) |
| 1504 | s->n_type |= BFD_MACH_O_N_EXT; |
| 1505 | |
| 1506 | /* This cuts both ways - we promote some things to external above. */ |
| 1507 | if (s->n_type & (BFD_MACH_O_N_PEXT | BFD_MACH_O_N_EXT)) |
| 1508 | S_SET_EXTERNAL (sp); |
| 1509 | |
| 1510 | return 0; |
| 1511 | } |
| 1512 | |
| 1513 | /* Support stabs for mach-o. */ |
| 1514 | |
| 1515 | void |
| 1516 | obj_mach_o_process_stab (int what, const char *string, |
| 1517 | int type, int other, int desc) |
| 1518 | { |
| 1519 | symbolS *symbolP; |
| 1520 | bfd_mach_o_asymbol *s; |
| 1521 | |
| 1522 | switch (what) |
| 1523 | { |
| 1524 | case 'd': |
| 1525 | symbolP = symbol_new ("", now_seg, frag_now_fix (), frag_now); |
| 1526 | /* Special stabd NULL name indicator. */ |
| 1527 | S_SET_NAME (symbolP, NULL); |
| 1528 | break; |
| 1529 | |
| 1530 | case 'n': |
| 1531 | case 's': |
| 1532 | symbolP = symbol_new (string, undefined_section, (valueT) 0, |
| 1533 | &zero_address_frag); |
| 1534 | pseudo_set (symbolP); |
| 1535 | break; |
| 1536 | |
| 1537 | default: |
| 1538 | as_bad(_("unrecognized stab type '%c'"), (char)what); |
| 1539 | abort (); |
| 1540 | break; |
| 1541 | } |
| 1542 | |
| 1543 | s = (bfd_mach_o_asymbol *) symbol_get_bfdsym (symbolP); |
| 1544 | s->n_type = type; |
| 1545 | s->n_desc = desc; |
| 1546 | /* For stabd, this will eventually get overwritten by the section number. */ |
| 1547 | s->n_sect = other; |
| 1548 | |
| 1549 | /* It's a debug symbol. */ |
| 1550 | s->symbol.flags |= BSF_DEBUGGING; |
| 1551 | |
| 1552 | /* We've set it - so check it, if you can, but don't try to create the |
| 1553 | flags. */ |
| 1554 | s->symbol.udata.i = SYM_MACHO_FIELDS_NOT_VALIDATED; |
| 1555 | } |
| 1556 | |
| 1557 | /* This is a place to check for any errors that we can't detect until we know |
| 1558 | what remains undefined at the end of assembly. */ |
| 1559 | |
| 1560 | static void |
| 1561 | obj_mach_o_check_before_writing (bfd *abfd ATTRIBUTE_UNUSED, |
| 1562 | asection *sec, |
| 1563 | void *unused ATTRIBUTE_UNUSED) |
| 1564 | { |
| 1565 | fixS *fixP; |
| 1566 | struct frchain *frchp; |
| 1567 | segment_info_type *seginfo = seg_info (sec); |
| 1568 | |
| 1569 | if (seginfo == NULL) |
| 1570 | return; |
| 1571 | |
| 1572 | /* We are not allowed subtractions where either of the operands is |
| 1573 | undefined. So look through the frags for any fixes to check. */ |
| 1574 | for (frchp = seginfo->frchainP; frchp != NULL; frchp = frchp->frch_next) |
| 1575 | for (fixP = frchp->fix_root; fixP != NULL; fixP = fixP->fx_next) |
| 1576 | { |
| 1577 | if (fixP->fx_addsy != NULL |
| 1578 | && fixP->fx_subsy != NULL |
| 1579 | && (! S_IS_DEFINED (fixP->fx_addsy) |
| 1580 | || ! S_IS_DEFINED (fixP->fx_subsy))) |
| 1581 | { |
| 1582 | segT add_symbol_segment = S_GET_SEGMENT (fixP->fx_addsy); |
| 1583 | segT sub_symbol_segment = S_GET_SEGMENT (fixP->fx_subsy); |
| 1584 | |
| 1585 | if (! S_IS_DEFINED (fixP->fx_addsy) |
| 1586 | && S_IS_DEFINED (fixP->fx_subsy)) |
| 1587 | { |
| 1588 | as_bad_where (fixP->fx_file, fixP->fx_line, |
| 1589 | _("`%s' can't be undefined in `%s' - `%s' {%s section}"), |
| 1590 | S_GET_NAME (fixP->fx_addsy), S_GET_NAME (fixP->fx_addsy), |
| 1591 | S_GET_NAME (fixP->fx_subsy), segment_name (sub_symbol_segment)); |
| 1592 | } |
| 1593 | else if (! S_IS_DEFINED (fixP->fx_subsy) |
| 1594 | && S_IS_DEFINED (fixP->fx_addsy)) |
| 1595 | { |
| 1596 | as_bad_where (fixP->fx_file, fixP->fx_line, |
| 1597 | _("`%s' can't be undefined in `%s' {%s section} - `%s'"), |
| 1598 | S_GET_NAME (fixP->fx_subsy), S_GET_NAME (fixP->fx_addsy), |
| 1599 | segment_name (add_symbol_segment), S_GET_NAME (fixP->fx_subsy)); |
| 1600 | } |
| 1601 | else |
| 1602 | { |
| 1603 | as_bad_where (fixP->fx_file, fixP->fx_line, |
| 1604 | _("`%s' and `%s' can't be undefined in `%s' - `%s'"), |
| 1605 | S_GET_NAME (fixP->fx_addsy), S_GET_NAME (fixP->fx_subsy), |
| 1606 | S_GET_NAME (fixP->fx_addsy), S_GET_NAME (fixP->fx_subsy)); |
| 1607 | } |
| 1608 | } |
| 1609 | } |
| 1610 | } |
| 1611 | |
| 1612 | /* Do any checks that we can't complete without knowing what's undefined. */ |
| 1613 | void |
| 1614 | obj_mach_o_pre_output_hook (void) |
| 1615 | { |
| 1616 | bfd_map_over_sections (stdoutput, obj_mach_o_check_before_writing, (char *) 0); |
| 1617 | } |
| 1618 | |
| 1619 | /* Here we count up frags in each subsection (where a sub-section is defined |
| 1620 | as starting with a non-local symbol). |
| 1621 | Note that, if there are no non-local symbols in a section, all the frags will |
| 1622 | be attached as one anonymous subsection. */ |
| 1623 | |
| 1624 | static void |
| 1625 | obj_mach_o_set_subsections (bfd *abfd ATTRIBUTE_UNUSED, |
| 1626 | asection *sec, |
| 1627 | void *unused ATTRIBUTE_UNUSED) |
| 1628 | { |
| 1629 | segment_info_type *seginfo = seg_info (sec); |
| 1630 | symbolS *cur_subsection = NULL; |
| 1631 | struct obj_mach_o_symbol_data *cur_subsection_data = NULL; |
| 1632 | fragS *frag; |
| 1633 | frchainS *chain; |
| 1634 | |
| 1635 | /* Protect against sections not created by gas. */ |
| 1636 | if (seginfo == NULL) |
| 1637 | return; |
| 1638 | |
| 1639 | /* Attach every frag to a subsection. */ |
| 1640 | for (chain = seginfo->frchainP; chain != NULL; chain = chain->frch_next) |
| 1641 | for (frag = chain->frch_root; frag != NULL; frag = frag->fr_next) |
| 1642 | { |
| 1643 | if (frag->obj_frag_data.subsection == NULL) |
| 1644 | frag->obj_frag_data.subsection = cur_subsection; |
| 1645 | else |
| 1646 | { |
| 1647 | cur_subsection = frag->obj_frag_data.subsection; |
| 1648 | cur_subsection_data = symbol_get_obj (cur_subsection); |
| 1649 | cur_subsection_data->subsection_size = 0; |
| 1650 | } |
| 1651 | if (cur_subsection_data != NULL) |
| 1652 | { |
| 1653 | /* Update subsection size. */ |
| 1654 | cur_subsection_data->subsection_size += frag->fr_fix; |
| 1655 | } |
| 1656 | } |
| 1657 | } |
| 1658 | |
| 1659 | /* Handle mach-o subsections-via-symbols counting up frags belonging to each |
| 1660 | sub-section. */ |
| 1661 | |
| 1662 | void |
| 1663 | obj_mach_o_pre_relax_hook (void) |
| 1664 | { |
| 1665 | bfd_map_over_sections (stdoutput, obj_mach_o_set_subsections, (char *) 0); |
| 1666 | } |
| 1667 | |
| 1668 | /* Zerofill and GB Zerofill sections must be sorted to follow all other |
| 1669 | sections in their segments. |
| 1670 | |
| 1671 | The native 'as' leaves the sections physically in the order they appear in |
| 1672 | the source, and adjusts the section VMAs to meet the constraint. |
| 1673 | |
| 1674 | We follow this for now - if nothing else, it makes comparison easier. |
| 1675 | |
| 1676 | An alternative implementation would be to sort the sections as ld requires. |
| 1677 | It might be advantageous to implement such a scheme in the future (or even |
| 1678 | to make the style of section ordering user-selectable). */ |
| 1679 | |
| 1680 | typedef struct obj_mach_o_set_vma_data |
| 1681 | { |
| 1682 | bfd_vma vma; |
| 1683 | unsigned vma_pass; |
| 1684 | unsigned zerofill_seen; |
| 1685 | unsigned gb_zerofill_seen; |
| 1686 | } obj_mach_o_set_vma_data; |
| 1687 | |
| 1688 | /* We do (possibly) three passes through to set the vma, so that: |
| 1689 | |
| 1690 | zerofill sections get VMAs after all others in their segment |
| 1691 | GB zerofill get VMAs last. |
| 1692 | |
| 1693 | As we go, we notice if we see any Zerofill or GB Zerofill sections, so that |
| 1694 | we can skip the additional passes if there's nothing to do. */ |
| 1695 | |
| 1696 | static void |
| 1697 | obj_mach_o_set_section_vma (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *v_p) |
| 1698 | { |
| 1699 | bfd_mach_o_section *ms = bfd_mach_o_get_mach_o_section (sec); |
| 1700 | unsigned bfd_align = bfd_section_alignment (sec); |
| 1701 | obj_mach_o_set_vma_data *p = (struct obj_mach_o_set_vma_data *)v_p; |
| 1702 | unsigned sectype = (ms->flags & BFD_MACH_O_SECTION_TYPE_MASK); |
| 1703 | unsigned zf; |
| 1704 | |
| 1705 | zf = 0; |
| 1706 | if (sectype == BFD_MACH_O_S_ZEROFILL) |
| 1707 | { |
| 1708 | zf = 1; |
| 1709 | p->zerofill_seen = zf; |
| 1710 | } |
| 1711 | else if (sectype == BFD_MACH_O_S_GB_ZEROFILL) |
| 1712 | { |
| 1713 | zf = 2; |
| 1714 | p->gb_zerofill_seen = zf; |
| 1715 | } |
| 1716 | |
| 1717 | if (p->vma_pass != zf) |
| 1718 | return; |
| 1719 | |
| 1720 | /* We know the section size now - so make a vma for the section just |
| 1721 | based on order. */ |
| 1722 | ms->size = bfd_section_size (sec); |
| 1723 | |
| 1724 | /* Make sure that the align agrees, and set to the largest value chosen. */ |
| 1725 | ms->align = ms->align > bfd_align ? ms->align : bfd_align; |
| 1726 | bfd_set_section_alignment (sec, ms->align); |
| 1727 | |
| 1728 | p->vma += (1 << ms->align) - 1; |
| 1729 | p->vma &= ~((1 << ms->align) - 1); |
| 1730 | ms->addr = p->vma; |
| 1731 | bfd_set_section_vma (sec, p->vma); |
| 1732 | p->vma += ms->size; |
| 1733 | } |
| 1734 | |
| 1735 | /* (potentially) three passes over the sections, setting VMA. We skip the |
| 1736 | {gb}zerofill passes if we didn't see any of the relevant sections. */ |
| 1737 | |
| 1738 | void obj_mach_o_post_relax_hook (void) |
| 1739 | { |
| 1740 | obj_mach_o_set_vma_data d; |
| 1741 | |
| 1742 | memset (&d, 0, sizeof (d)); |
| 1743 | |
| 1744 | bfd_map_over_sections (stdoutput, obj_mach_o_set_section_vma, (char *) &d); |
| 1745 | if ((d.vma_pass = d.zerofill_seen) != 0) |
| 1746 | bfd_map_over_sections (stdoutput, obj_mach_o_set_section_vma, (char *) &d); |
| 1747 | if ((d.vma_pass = d.gb_zerofill_seen) != 0) |
| 1748 | bfd_map_over_sections (stdoutput, obj_mach_o_set_section_vma, (char *) &d); |
| 1749 | } |
| 1750 | |
| 1751 | static void |
| 1752 | obj_mach_o_set_indirect_symbols (bfd *abfd, asection *sec, |
| 1753 | void *xxx ATTRIBUTE_UNUSED) |
| 1754 | { |
| 1755 | bfd_vma sect_size = bfd_section_size (sec); |
| 1756 | bfd_mach_o_section *ms = bfd_mach_o_get_mach_o_section (sec); |
| 1757 | unsigned lazy = 0; |
| 1758 | |
| 1759 | /* See if we have any indirect syms to consider. */ |
| 1760 | if (indirect_syms == NULL) |
| 1761 | return; |
| 1762 | |
| 1763 | /* Process indirect symbols. |
| 1764 | Check for errors, if OK attach them as a flat array to the section |
| 1765 | for which they are defined. */ |
| 1766 | |
| 1767 | switch (ms->flags & BFD_MACH_O_SECTION_TYPE_MASK) |
| 1768 | { |
| 1769 | case BFD_MACH_O_S_SYMBOL_STUBS: |
| 1770 | case BFD_MACH_O_S_LAZY_SYMBOL_POINTERS: |
| 1771 | lazy = LAZY; |
| 1772 | /* Fall through. */ |
| 1773 | case BFD_MACH_O_S_NON_LAZY_SYMBOL_POINTERS: |
| 1774 | { |
| 1775 | unsigned int nactual = 0; |
| 1776 | unsigned int ncalc; |
| 1777 | obj_mach_o_indirect_sym *isym; |
| 1778 | obj_mach_o_indirect_sym *list = NULL; |
| 1779 | obj_mach_o_indirect_sym *list_tail = NULL; |
| 1780 | unsigned long eltsiz = |
| 1781 | bfd_mach_o_section_get_entry_size (abfd, ms); |
| 1782 | |
| 1783 | for (isym = indirect_syms; isym != NULL; isym = isym->next) |
| 1784 | { |
| 1785 | if (isym->sect == sec) |
| 1786 | { |
| 1787 | nactual++; |
| 1788 | if (list == NULL) |
| 1789 | list = isym; |
| 1790 | else |
| 1791 | list_tail->next = isym; |
| 1792 | list_tail = isym; |
| 1793 | } |
| 1794 | } |
| 1795 | |
| 1796 | /* If none are in this section, stop here. */ |
| 1797 | if (nactual == 0) |
| 1798 | break; |
| 1799 | |
| 1800 | /* If we somehow added indirect symbols to a section with a zero |
| 1801 | entry size, we're dead ... */ |
| 1802 | gas_assert (eltsiz != 0); |
| 1803 | |
| 1804 | ncalc = (unsigned int) (sect_size / eltsiz); |
| 1805 | if (nactual != ncalc) |
| 1806 | as_bad (_("the number of .indirect_symbols defined in section %s" |
| 1807 | " does not match the number expected (%d defined, %d" |
| 1808 | " expected)"), sec->name, nactual, ncalc); |
| 1809 | else |
| 1810 | { |
| 1811 | unsigned n; |
| 1812 | bfd_mach_o_asymbol *sym; |
| 1813 | |
| 1814 | /* FIXME: It seems that there can be more indirect symbols |
| 1815 | than is computed by the loop above. So be paranoid and |
| 1816 | allocate enough space for every symbol to be indirect. |
| 1817 | See PR 21939 for an example of where this is needed. */ |
| 1818 | if (nactual < bfd_get_symcount (abfd)) |
| 1819 | nactual = bfd_get_symcount (abfd); |
| 1820 | |
| 1821 | ms->indirect_syms = |
| 1822 | bfd_zalloc (abfd, |
| 1823 | nactual * sizeof (bfd_mach_o_asymbol *)); |
| 1824 | |
| 1825 | if (ms->indirect_syms == NULL) |
| 1826 | as_fatal (_("internal error: failed to allocate %d indirect" |
| 1827 | "symbol pointers"), nactual); |
| 1828 | |
| 1829 | for (isym = list, n = 0; isym != NULL; isym = isym->next, n++) |
| 1830 | { |
| 1831 | sym = (bfd_mach_o_asymbol *)symbol_get_bfdsym (isym->sym); |
| 1832 | /* Array is init to NULL & NULL signals a local symbol |
| 1833 | If the section is lazy-bound, we need to keep the |
| 1834 | reference to the symbol, since dyld can override. |
| 1835 | |
| 1836 | Absolute symbols are handled specially. */ |
| 1837 | if (sym->symbol.section == bfd_abs_section_ptr) |
| 1838 | { |
| 1839 | if (n >= nactual) |
| 1840 | as_fatal (_("internal error: more indirect mach-o symbols than expected")); |
| 1841 | ms->indirect_syms[n] = sym; |
| 1842 | } |
| 1843 | else if (S_IS_LOCAL (isym->sym) && ! lazy) |
| 1844 | ; |
| 1845 | else |
| 1846 | { |
| 1847 | if (sym == NULL) |
| 1848 | ; |
| 1849 | /* If the symbols is external ... */ |
| 1850 | else if (S_IS_EXTERNAL (isym->sym) |
| 1851 | || (sym->n_type & BFD_MACH_O_N_EXT) |
| 1852 | || ! S_IS_DEFINED (isym->sym) |
| 1853 | || lazy) |
| 1854 | { |
| 1855 | sym->n_desc &= ~LAZY; |
| 1856 | /* ... it can be lazy, if not defined or hidden. */ |
| 1857 | if ((sym->n_type & BFD_MACH_O_N_TYPE) |
| 1858 | == BFD_MACH_O_N_UNDF |
| 1859 | && ! (sym->n_type & BFD_MACH_O_N_PEXT) |
| 1860 | && (sym->n_type & BFD_MACH_O_N_EXT)) |
| 1861 | sym->n_desc |= lazy; |
| 1862 | if (n >= nactual) |
| 1863 | as_fatal (_("internal error: more indirect mach-o symbols than expected")); |
| 1864 | ms->indirect_syms[n] = sym; |
| 1865 | } |
| 1866 | } |
| 1867 | } |
| 1868 | } |
| 1869 | } |
| 1870 | break; |
| 1871 | |
| 1872 | default: |
| 1873 | break; |
| 1874 | } |
| 1875 | } |
| 1876 | |
| 1877 | /* The process of relocation could alter what's externally visible, thus we |
| 1878 | leave setting the indirect symbols until last. */ |
| 1879 | |
| 1880 | void |
| 1881 | obj_mach_o_frob_file_after_relocs (void) |
| 1882 | { |
| 1883 | bfd_map_over_sections (stdoutput, obj_mach_o_set_indirect_symbols, (char *) 0); |
| 1884 | } |
| 1885 | |
| 1886 | /* Reverse relocations order to make ld happy. */ |
| 1887 | |
| 1888 | void |
| 1889 | obj_mach_o_reorder_section_relocs (asection *sec, arelent **rels, unsigned int n) |
| 1890 | { |
| 1891 | unsigned int i; |
| 1892 | unsigned int max = n / 2; |
| 1893 | |
| 1894 | for (i = 0; i < max; i++) |
| 1895 | { |
| 1896 | arelent *r = rels[i]; |
| 1897 | rels[i] = rels[n - i - 1]; |
| 1898 | rels[n - i - 1] = r; |
| 1899 | } |
| 1900 | bfd_set_reloc (stdoutput, sec, rels, n); |
| 1901 | } |
| 1902 | |
| 1903 | /* Relocation rules are different in frame sections. */ |
| 1904 | |
| 1905 | static int |
| 1906 | obj_mach_o_is_frame_section (segT sec) |
| 1907 | { |
| 1908 | int l; |
| 1909 | l = strlen (segment_name (sec)); |
| 1910 | if ((l == 9 && strncmp (".eh_frame", segment_name (sec), 9) == 0) |
| 1911 | || (l == 12 && strncmp (".debug_frame", segment_name (sec), 12) == 0)) |
| 1912 | return 1; |
| 1913 | return 0; |
| 1914 | } |
| 1915 | |
| 1916 | /* Unless we're in a frame section, we need to force relocs to be generated for |
| 1917 | local subtractions. We might eliminate them later (if they are within the |
| 1918 | same sub-section) but we don't know that at the point that this decision is |
| 1919 | being made. */ |
| 1920 | |
| 1921 | int |
| 1922 | obj_mach_o_allow_local_subtract (expressionS * left ATTRIBUTE_UNUSED, |
| 1923 | expressionS * right ATTRIBUTE_UNUSED, |
| 1924 | segT seg) |
| 1925 | { |
| 1926 | /* Don't interfere if it's one of the GAS internal sections. */ |
| 1927 | if (! SEG_NORMAL (seg)) |
| 1928 | return 1; |
| 1929 | |
| 1930 | /* Allow in frame sections, otherwise emit a reloc. */ |
| 1931 | return obj_mach_o_is_frame_section (seg); |
| 1932 | } |
| 1933 | |
| 1934 | int |
| 1935 | obj_mach_o_in_different_subsection (symbolS *a, symbolS *b) |
| 1936 | { |
| 1937 | fragS *fa; |
| 1938 | fragS *fb; |
| 1939 | |
| 1940 | if (S_GET_SEGMENT (a) != S_GET_SEGMENT (b) |
| 1941 | || !S_IS_DEFINED (a) |
| 1942 | || !S_IS_DEFINED (b)) |
| 1943 | { |
| 1944 | /* Not in the same segment, or undefined symbol. */ |
| 1945 | return 1; |
| 1946 | } |
| 1947 | |
| 1948 | fa = symbol_get_frag (a); |
| 1949 | fb = symbol_get_frag (b); |
| 1950 | if (fa == NULL || fb == NULL) |
| 1951 | { |
| 1952 | /* One of the symbols is not in a subsection. */ |
| 1953 | return 1; |
| 1954 | } |
| 1955 | |
| 1956 | return fa->obj_frag_data.subsection != fb->obj_frag_data.subsection; |
| 1957 | } |
| 1958 | |
| 1959 | int |
| 1960 | obj_mach_o_force_reloc_sub_same (fixS *fix, segT seg) |
| 1961 | { |
| 1962 | if (! SEG_NORMAL (seg)) |
| 1963 | return 1; |
| 1964 | return obj_mach_o_in_different_subsection (fix->fx_addsy, fix->fx_subsy); |
| 1965 | } |
| 1966 | |
| 1967 | int |
| 1968 | obj_mach_o_force_reloc_sub_local (fixS *fix, segT seg ATTRIBUTE_UNUSED) |
| 1969 | { |
| 1970 | return obj_mach_o_in_different_subsection (fix->fx_addsy, fix->fx_subsy); |
| 1971 | } |
| 1972 | |
| 1973 | int |
| 1974 | obj_mach_o_force_reloc (fixS *fix) |
| 1975 | { |
| 1976 | if (generic_force_reloc (fix)) |
| 1977 | return 1; |
| 1978 | |
| 1979 | /* Force a reloc if the target is not in the same subsection. |
| 1980 | FIXME: handle (a - b) where a and b belongs to the same subsection ? */ |
| 1981 | if (fix->fx_addsy != NULL) |
| 1982 | { |
| 1983 | symbolS *subsec = fix->fx_frag->obj_frag_data.subsection; |
| 1984 | symbolS *targ = fix->fx_addsy; |
| 1985 | |
| 1986 | /* There might be no subsections at all. */ |
| 1987 | if (subsec == NULL) |
| 1988 | return 0; |
| 1989 | |
| 1990 | if (S_GET_SEGMENT (targ) == absolute_section) |
| 1991 | return 0; |
| 1992 | |
| 1993 | return obj_mach_o_in_different_subsection (targ, subsec); |
| 1994 | } |
| 1995 | return 0; |
| 1996 | } |