nsz Git - libfirm/blob - ir/be/begnuas.c

   1 /*
   2  * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
   3  *
   4  * This file is part of libFirm.
   5  *
   6  * This file may be distributed and/or modified under the terms of the
   7  * GNU General Public License version 2 as published by the Free Software
   8  * Foundation and appearing in the file LICENSE.GPL included in the
   9  * packaging of this file.
  10  *
  11  * Licensees holding valid libFirm Professional Edition licenses may use
  12  * this file in accordance with the libFirm Commercial License.
  13  * Agreement provided with the Software.
  14  *
  15  * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
  16  * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  17  * PURPOSE.
  18  */
  19
  20 /**
  21  * @file
  22  * @brief       Dumps global variables and constants as gas assembler.
  23  * @author      Christian Wuerdig, Matthias Braun
  24  * @date        04.11.2005
  25  * @version     $Id$
  26  */
  27 #include "config.h"
  28
  29 #include "begnuas.h"
  30
  31 #include <stdlib.h>
  32 #include <string.h>
  33 #include <ctype.h>
  34 #include <assert.h>
  35
  36 #include "obst.h"
  37 #include "tv.h"
  38 #include "irnode.h"
  39 #include "irprog.h"
  40 #include "entity_t.h"
  41 #include "error.h"
  42
  43 #include "be_t.h"
  44 #include "beemitter.h"
  45 #include "be_dbgout.h"
  46
  47 /** by default, we generate assembler code for the Linux gas */
  48 object_file_format_t  be_gas_object_file_format = OBJECT_FILE_FORMAT_ELF;
  49 bool                  be_gas_emit_types         = true;
  50 char                  be_gas_elf_type_char      = '@';
  51
  52 static be_gas_section_t current_section = (be_gas_section_t) -1;
  53
  54 /**
  55  * Return the pseudo-instruction to be issued for a section switch
  56  * depending on the current flavour.
  57  *
  58  * @param section  the section to switch to
  59  *
  60  * @return  the pseudo-instruction
  61  */
  62 static const char *get_section_name(be_gas_section_t section)
  63 {
  64         static const char *text[OBJECT_FILE_FORMAT_LAST+1][GAS_SECTION_LAST+1] = {
  65                 { /* OBJECT_FILE_FORMAT_ELF */
  66                         ".section\t.text",
  67                         ".section\t.data",
  68                         ".section\t.rodata",
  69                         ".section\t.bss",
  70                         ".section\t.tdata,\"awT\",@progbits",
  71                         ".section\t.tbss,\"awT\",@nobits",
  72                         ".section\t.ctors,\"aw\",@progbits",
  73                         ".section\t.dtors,\"aw\",@progbits",
  74                         NULL, /* no cstring section */
  75                         NULL,
  76                         NULL
  77                 },
  78                 { /* OBJECT_FILE_FORMAT_COFF */
  79                         ".section\t.text",
  80                         ".section\t.data",
  81                         ".section .rdata,\"dr\"",
  82                         ".section\t.bss",
  83                         ".section\t.tdata,\"awT\",@progbits",
  84                         ".section\t.tbss,\"awT\",@nobits",
  85                         ".section\t.ctors,\"w\"",
  86                         ".section\t.dtors,\"w\"",
  87                         NULL,
  88                         NULL,
  89                         NULL
  90                 },
  91                 { /* OBJECT_FILE_FORMAT_MACH_O */
  92                         ".text",
  93                         ".data",
  94                         ".const",
  95                         ".data",
  96                         NULL,             /* TLS is not supported on Mach-O */
  97                         NULL,             /* TLS is not supported on Mach-O */
  98                         ".mod_init_func",
  99                         ".mod_term_func",
 100                         ".cstring",
 101                         ".section\t__IMPORT,__jump_table,symbol_stubs,self_modifying_code+pure_instructions,5",
 102                         ".section\t__IMPORT,__pointers,non_lazy_symbol_pointers"
 103                 }
 104         };
 105
 106         assert((int) be_gas_object_file_format >= 0
 107                         && be_gas_object_file_format <= OBJECT_FILE_FORMAT_LAST);
 108         assert((int) section >= 0 && section <= GAS_SECTION_LAST);
 109         return text[be_gas_object_file_format][section];
 110 }
 111
 112 void be_gas_emit_switch_section(be_gas_section_t section)
 113 {
 114         if (current_section == section)
 115                 return;
 116
 117         be_emit_char('\t');
 118         be_emit_string(get_section_name(section));
 119         be_emit_char('\n');
 120         be_emit_write_line();
 121         current_section = section;
 122 }
 123
 124 static void emit_entity_visibility(const ir_entity *entity)
 125 {
 126         ir_visibility visibility = get_entity_visibility(entity);
 127         ir_linkage    linkage    = get_entity_linkage(entity);
 128
 129         if (visibility != ir_visibility_local) {
 130                 be_emit_cstring(".globl ");
 131                 be_emit_ident(get_entity_ld_ident(entity));
 132                 be_emit_char('\n');
 133                 be_emit_write_line();
 134         }
 135         if (linkage & IR_LINKAGE_WEAK) {
 136                 if (! (linkage & IR_LINKAGE_MERGE)) {
 137                         panic("Weak symbols only supported in combination with IR_LINKAGE_MERGE on this architecture");
 138                 }
 139                 be_emit_cstring(".weak ");
 140                 be_emit_ident(get_entity_ld_ident(entity));
 141                 be_emit_char('\n');
 142                 be_emit_write_line();
 143         }
 144 }
 145
 146 void be_gas_emit_function_prolog(ir_entity *entity, unsigned po2alignment)
 147 {
 148         const char *name = get_entity_ld_name(entity);
 149
 150         be_gas_emit_switch_section(GAS_SECTION_TEXT);
 151
 152         /* write the begin line (makes the life easier for scripts parsing the
 153          * assembler) */
 154         be_emit_write_line();
 155         be_emit_cstring("# -- Begin  ");
 156         be_emit_string(name);
 157         be_emit_char('\n');
 158         be_emit_write_line();
 159
 160         if (po2alignment > 0) {
 161                 const char *fill_byte = "";
 162                 unsigned    maximum_skip = (1 << po2alignment) - 1;
 163                 /* gcc fills space between function with 0x90... */
 164                 if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 165                         fill_byte = "0x90";
 166                 }
 167                 be_emit_cstring("\t.p2align ");
 168                 be_emit_irprintf("%u,%s,%u\n", po2alignment, fill_byte, maximum_skip);
 169                 be_emit_write_line();
 170         }
 171         emit_entity_visibility(entity);
 172
 173         switch (be_gas_object_file_format) {
 174         case OBJECT_FILE_FORMAT_ELF:
 175                 be_emit_cstring("\t.type\t");
 176                 be_emit_string(name);
 177                 be_emit_cstring(", ");
 178                 be_emit_char(be_gas_elf_type_char);
 179                 be_emit_cstring("function\n");
 180                 be_emit_write_line();
 181                 break;
 182         case OBJECT_FILE_FORMAT_COFF:
 183                 be_emit_cstring("\t.def\t");
 184                 be_emit_string(name);
 185                 be_emit_cstring(";");
 186                 if (get_entity_visibility(entity) == ir_visibility_local) {
 187                         be_emit_cstring("\t.scl\t3;");
 188                 } else {
 189                         be_emit_cstring("\t.scl\t2;");
 190                 }
 191                 be_emit_cstring("\t.type\t32;\t.endef\n");
 192                 be_emit_write_line();
 193                 break;
 194         case OBJECT_FILE_FORMAT_MACH_O:
 195                 break;
 196         }
 197         be_emit_string(name);
 198         be_emit_cstring(":\n");
 199         be_emit_write_line();
 200 }
 201
 202 void be_gas_emit_function_epilog(ir_entity *entity)
 203 {
 204         const char *name = get_entity_ld_name(entity);
 205
 206         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_ELF) {
 207                 be_emit_cstring("\t.size\t");
 208                 be_emit_string(name);
 209                 be_emit_cstring(", .-");
 210                 be_emit_string(name);
 211                 be_emit_char('\n');
 212                 be_emit_write_line();
 213         }
 214
 215         be_emit_cstring("# -- End  ");
 216         be_emit_string(name);
 217         be_emit_char('\n');
 218         be_emit_write_line();
 219 }
 220
 221 /**
 222  * An environment containing all needed dumper data.
 223  * Currently we create the file completely in memory first, then
 224  * write it to the disk. This is an artifact from the old C-generating backend
 225  * and even there NOT needed. So we might change it in the future.
 226  */
 227 typedef struct _be_gas_decl_env {
 228         be_gas_section_t     section;
 229         const be_main_env_t *main_env;
 230 } be_gas_decl_env_t;
 231
 232 /************************************************************************/
 233
 234 /**
 235  * Output a tarval.
 236  *
 237  * @param tv     the tarval
 238  * @param bytes  the width of the tarvals value in bytes
 239  */
 240 static void dump_arith_tarval(tarval *tv, int bytes)
 241 {
 242         switch (bytes) {
 243         case 1:
 244                 be_emit_irprintf("0x%02x", get_tarval_sub_bits(tv, 0));
 245                 return;
 246
 247         case 2:
 248                 be_emit_irprintf("0x%02x%02x", get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 249                 return;
 250
 251         case 4:
 252                 be_emit_irprintf("0x%02x%02x%02x%02x",
 253                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 254                 return;
 255
 256         case 8:
 257                 be_emit_irprintf("0x%02x%02x%02x%02x%02x%02x%02x%02x",
 258                         get_tarval_sub_bits(tv, 7), get_tarval_sub_bits(tv, 6), get_tarval_sub_bits(tv, 5), get_tarval_sub_bits(tv, 4),
 259                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 260                 return;
 261
 262         case 12:
 263                 /* Beware: Mixed endian output!  One little endian number emitted as
 264                  * three longs.  Each long initializer is written in big endian. */
 265                 be_emit_irprintf(
 266                         "\t.long\t0x%02x%02x%02x%02x\n"
 267                         "\t.long\t0x%02x%02x%02x%02x\n"
 268                         "\t.long\t0x%02x%02x%02x%02x",
 269                         get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
 270                         get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0),
 271                         get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
 272                         get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
 273                         get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
 274                         get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8)
 275                 );
 276                 return;
 277
 278         case 16:
 279                 /* Beware: Mixed endian output!  One little endian number emitted as
 280                  * three longs.  Each long initializer is written in big endian. */
 281                 be_emit_irprintf(
 282                         "\t.long\t0x%02x%02x%02x%02x\n"
 283                         "\t.long\t0x%02x%02x%02x%02x\n"
 284                         "\t.long\t0x%02x%02x%02x%02x\n"
 285                         "\t.long\t0x%02x%02x%02x%02x",
 286                         get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
 287                         get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0),
 288                         get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
 289                         get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
 290                         get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
 291                         get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8),
 292                         get_tarval_sub_bits(tv, 15), get_tarval_sub_bits(tv, 14),
 293                         get_tarval_sub_bits(tv, 13), get_tarval_sub_bits(tv, 12)
 294                 );
 295                 return;
 296         }
 297
 298         panic("Can't dump a tarval with %d bytes", bytes);
 299 }
 300
 301 /**
 302  * Return the label prefix for labeled blocks.
 303  */
 304 const char *be_gas_block_label_prefix(void)
 305 {
 306         return ".LG";
 307 }
 308
 309 /**
 310  * Return the label prefix for labeled instructions.
 311  */
 312 const char *be_gas_insn_label_prefix(void)
 313 {
 314         return ".LE";
 315 }
 316
 317 void be_gas_emit_entity(ir_entity *entity)
 318 {
 319         if (entity->type == firm_code_type) {
 320                 ir_label_t label = get_entity_label(entity);
 321                 be_emit_string(be_gas_block_label_prefix());
 322                 be_emit_irprintf("%lu", label);
 323         } else {
 324                 be_emit_ident(get_entity_ld_ident(entity));
 325         }
 326 }
 327
 328 /**
 329  * Return the tarval of an atomic initializer.
 330  *
 331  * @param init  a node representing the initializer (on the const code irg)
 332  *
 333  * @return the tarval
 334  */
 335 static tarval *get_atomic_init_tv(ir_node *init)
 336 {
 337         for (;;) {
 338                 ir_mode *mode = get_irn_mode(init);
 339
 340                 switch (get_irn_opcode(init)) {
 341
 342                 case iro_Cast:
 343                         init = get_Cast_op(init);
 344                         continue;
 345
 346                 case iro_Conv:
 347                         init = get_Conv_op(init);
 348                         continue;
 349
 350                 case iro_Const:
 351                         return get_Const_tarval(init);
 352
 353                 case iro_SymConst:
 354                         switch (get_SymConst_kind(init)) {
 355                         case symconst_type_size:
 356                                 return new_tarval_from_long(get_type_size_bytes(get_SymConst_type(init)), mode);
 357
 358                         case symconst_type_align:
 359                                 return new_tarval_from_long(get_type_alignment_bytes(get_SymConst_type(init)), mode);
 360
 361                         case symconst_ofs_ent:
 362                                 return new_tarval_from_long(get_entity_offset(get_SymConst_entity(init)), mode);
 363
 364                         case symconst_enum_const:
 365                                 return get_enumeration_value(get_SymConst_enum(init));
 366
 367                         default:
 368                                 return NULL;
 369                         }
 370
 371                 default:
 372                         return NULL;
 373                 }
 374         }
 375 }
 376
 377 /**
 378  * Dump an atomic value.
 379  *
 380  * @param env   the gas output environment
 381  * @param init  a node representing the atomic value (on the const code irg)
 382  */
 383 static void do_dump_atomic_init(be_gas_decl_env_t *env, ir_node *init)
 384 {
 385         ir_mode *mode = get_irn_mode(init);
 386         int bytes     = get_mode_size_bytes(mode);
 387         tarval *tv;
 388         ir_entity *ent;
 389
 390         init = skip_Id(init);
 391
 392         switch (get_irn_opcode(init)) {
 393         case iro_Cast:
 394                 do_dump_atomic_init(env, get_Cast_op(init));
 395                 return;
 396
 397         case iro_Conv:
 398                 do_dump_atomic_init(env, get_Conv_op(init));
 399                 return;
 400
 401         case iro_Const:
 402                 tv = get_Const_tarval(init);
 403
 404                 /* it's a arithmetic value */
 405                 dump_arith_tarval(tv, bytes);
 406                 return;
 407
 408         case iro_SymConst:
 409                 switch (get_SymConst_kind(init)) {
 410                 case symconst_addr_name:
 411                         be_emit_ident(get_SymConst_name(init));
 412                         break;
 413
 414                 case symconst_addr_ent:
 415                         ent = get_SymConst_entity(init);
 416                         be_gas_emit_entity(ent);
 417                         break;
 418
 419                 case symconst_ofs_ent:
 420                         ent = get_SymConst_entity(init);
 421                         be_emit_irprintf("%d", get_entity_offset(ent));
 422                         break;
 423
 424                 case symconst_type_size:
 425                         be_emit_irprintf("%u", get_type_size_bytes(get_SymConst_type(init)));
 426                         break;
 427
 428                 case symconst_type_align:
 429                         be_emit_irprintf("%u", get_type_alignment_bytes(get_SymConst_type(init)));
 430                         break;
 431
 432                 case symconst_enum_const:
 433                         tv = get_enumeration_value(get_SymConst_enum(init));
 434                         dump_arith_tarval(tv, bytes);
 435                         break;
 436
 437                 default:
 438                         assert(!"dump_atomic_init(): don't know how to init from this SymConst");
 439                 }
 440                 return;
 441
 442         case iro_Add:
 443                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 444                         panic("Constant must be int or pointer for '+' to work");
 445                 }
 446                 do_dump_atomic_init(env, get_Add_left(init));
 447                 be_emit_cstring(" + ");
 448                 do_dump_atomic_init(env, get_Add_right(init));
 449                 return;
 450
 451         case iro_Sub:
 452                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 453                         panic("Constant must be int or pointer for '-' to work");
 454                 }
 455                 do_dump_atomic_init(env, get_Sub_left(init));
 456                 be_emit_cstring(" - ");
 457                 do_dump_atomic_init(env, get_Sub_right(init));
 458                 return;
 459
 460         case iro_Mul:
 461                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 462                         panic("Constant must be int or pointer for '*' to work");
 463                 }
 464                 do_dump_atomic_init(env, get_Mul_left(init));
 465                 be_emit_cstring(" * ");
 466                 do_dump_atomic_init(env, get_Mul_right(init));
 467                 return;
 468
 469         case iro_Unknown:
 470                 be_emit_cstring("0");
 471                 return;
 472
 473         default:
 474                 panic("dump_atomic_init(): unsupported IR-node %+F", init);
 475         }
 476 }
 477
 478 /**
 479  * Dumps the type for given size (.byte, .long, ...)
 480  *
 481  * @param size  the size in bytes
 482  */
 483 static void dump_size_type(size_t size) {
 484         switch (size) {
 485         case 1:
 486                 be_emit_cstring("\t.byte\t");
 487                 break;
 488
 489         case 2:
 490                 be_emit_cstring("\t.short\t");
 491                 break;
 492
 493         case 4:
 494                 be_emit_cstring("\t.long\t");
 495                 break;
 496
 497         case 8:
 498                 be_emit_cstring("\t.quad\t");
 499                 break;
 500
 501         case 10:
 502         case 12:
 503         case 16: /* Note: .octa does not work on mac */
 504                 /* handled in arith */
 505                 break;
 506
 507         default:
 508                 panic("Try to dump a type with %u bytes", (unsigned)size);
 509         }
 510 }
 511
 512 /**
 513  * Emit an atomic value.
 514  *
 515  * @param env   the gas output environment
 516  * @param init  a node representing the atomic value (on the const code irg)
 517  */
 518 static void dump_atomic_init(be_gas_decl_env_t *env, ir_node *init)
 519 {
 520         ir_mode *mode = get_irn_mode(init);
 521         int bytes     = get_mode_size_bytes(mode);
 522
 523         dump_size_type(bytes);
 524         do_dump_atomic_init(env, init);
 525         be_emit_char('\n');
 526         be_emit_write_line();
 527 }
 528
 529 /************************************************************************/
 530 /* Routines to dump global variables                                    */
 531 /************************************************************************/
 532
 533 static int initializer_is_string_const(const ir_initializer_t *initializer)
 534 {
 535         size_t i, len;
 536         int found_printable = 0;
 537
 538         if (initializer->kind != IR_INITIALIZER_COMPOUND)
 539                 return 0;
 540
 541         len = initializer->compound.n_initializers;
 542         if (len < 1)
 543                 return 0;
 544         for (i = 0; i < len; ++i) {
 545                 int               c;
 546                 tarval           *tv;
 547                 ir_mode          *mode;
 548                 ir_initializer_t *sub_initializer
 549                         = initializer->compound.initializers[i];
 550
 551                 if (sub_initializer->kind != IR_INITIALIZER_TARVAL)
 552                         return 0;
 553
 554                 tv   = sub_initializer->tarval.value;
 555                 mode = get_tarval_mode(tv);
 556
 557                 if (!mode_is_int(mode) || get_mode_size_bits(mode) != 8)
 558                         return 0;
 559
 560                 c = get_tarval_long(tv);
 561                 if (isgraph(c) || isspace(c))
 562                         found_printable = 1;
 563                 else if (c != 0)
 564                         return 0;
 565
 566                 if (i == len - 1 && c != '\0')
 567                         return 0;
 568         }
 569
 570         return found_printable;
 571 }
 572
 573 /**
 574  * Determine if an entity is a string constant
 575  * @param ent The entity
 576  * @return 1 if it is a string constant, 0 otherwise
 577  */
 578 static int ent_is_string_const(const ir_entity *ent)
 579 {
 580         ir_type *type, *element_type;
 581         ir_mode *mode;
 582         int i, c, n;
 583
 584         type = get_entity_type(ent);
 585
 586         /* if it's an array */
 587         if (!is_Array_type(type))
 588                 return 0;
 589
 590         element_type = get_array_element_type(type);
 591
 592         /* and the array's element type is primitive */
 593         if (!is_Primitive_type(element_type))
 594                 return 0;
 595
 596         /* and the mode of the element type is an int of
 597          * the same size as the byte mode */
 598         mode = get_type_mode(element_type);
 599         if (!mode_is_int(mode) || get_mode_size_bits(mode) != 8)
 600                 return 0;
 601
 602         if (ent->initializer != NULL) {
 603                 return initializer_is_string_const(ent->initializer);
 604         } else if (entity_has_compound_ent_values(ent)) {
 605                 int found_printable = 0;
 606                 /* if it contains only printable chars and a 0 at the end */
 607                 n = get_compound_ent_n_values(ent);
 608                 for (i = 0; i < n; ++i) {
 609                         ir_node *irn = get_compound_ent_value(ent, i);
 610                         if (! is_Const(irn))
 611                                 return 0;
 612
 613                         c = (int) get_tarval_long(get_Const_tarval(irn));
 614
 615                         if (isgraph(c) || isspace(c))
 616                                 found_printable = 1;
 617                         else if (c != 0)
 618                                 return 0;
 619
 620                         if (i == n - 1 && c != '\0')
 621                                 return 0;
 622                 }
 623                 return found_printable;
 624         }
 625
 626         return 0;
 627 }
 628
 629 static bool initializer_is_null(const ir_initializer_t *initializer)
 630 {
 631         switch (initializer->kind) {
 632         case IR_INITIALIZER_NULL:
 633                 return true;
 634         case IR_INITIALIZER_TARVAL: {
 635                 tarval *tv = initializer->tarval.value;
 636                 return tarval_is_null(tv);
 637         }
 638         case IR_INITIALIZER_CONST: {
 639                 ir_node *value = initializer->consti.value;
 640                 if (!is_Const(value))
 641                         return false;
 642                 return is_Const_null(value);
 643         }
 644         case IR_INITIALIZER_COMPOUND: {
 645                 size_t i;
 646                 for (i = 0; i < initializer->compound.n_initializers; ++i) {
 647                         ir_initializer_t *subinitializer
 648                                 = initializer->compound.initializers[i];
 649                         if (!initializer_is_null(subinitializer))
 650                                 return false;
 651                 }
 652                 return true;
 653         }
 654         }
 655         panic("invalid initializer in initializer_is_null");
 656 }
 657
 658 static bool entity_is_null(const ir_entity *entity)
 659 {
 660         if (entity->initializer != NULL) {
 661                 return initializer_is_null(entity->initializer);
 662         } else if (entity_has_compound_ent_values(entity)) {
 663                 /* I'm too lazy to implement this case as compound graph paths will be
 664                  * remove anyway in the future */
 665         }
 666         /* uninitialized, NULL is fine */
 667         return true;
 668 }
 669
 670 /**
 671  * Dump a string constant.
 672  * No checks are made!!
 673  *
 674  * @param ent  The entity to dump.
 675  */
 676 static void dump_string_cst(const ir_entity *ent)
 677 {
 678         int      i, len;
 679         int      output_len;
 680         ir_type *type;
 681         int      type_size;
 682         int      remaining_space;
 683
 684         len        = get_compound_ent_n_values(ent);
 685         output_len = len;
 686         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 687                 be_emit_cstring("\t.ascii \"");
 688         } else {
 689                 be_emit_cstring("\t.string \"");
 690                 output_len -= 1;
 691         }
 692
 693         for (i = 0; i < output_len; ++i) {
 694                 ir_node *irn;
 695                 int c;
 696
 697                 irn = get_compound_ent_value(ent, i);
 698                 c = (int) get_tarval_long(get_Const_tarval(irn));
 699
 700                 switch (c) {
 701                 case '"' : be_emit_cstring("\\\""); break;
 702                 case '\n': be_emit_cstring("\\n"); break;
 703                 case '\r': be_emit_cstring("\\r"); break;
 704                 case '\t': be_emit_cstring("\\t"); break;
 705                 case '\\': be_emit_cstring("\\\\"); break;
 706                 default  :
 707                         if (isprint(c))
 708                                 be_emit_char(c);
 709                         else
 710                                 be_emit_irprintf("\\%o", c);
 711                         break;
 712                 }
 713         }
 714         be_emit_cstring("\"\n");
 715         be_emit_write_line();
 716
 717         type            = get_entity_type(ent);
 718         type_size       = get_type_size_bytes(type);
 719         remaining_space = type_size - len;
 720         assert(remaining_space >= 0);
 721         if (remaining_space > 0) {
 722                 be_emit_irprintf("\t.zero\t%d\n", remaining_space);
 723         }
 724 }
 725
 726 static void dump_string_initializer(const ir_initializer_t *initializer)
 727 {
 728         size_t i, len;
 729
 730         len = initializer->compound.n_initializers;
 731         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 732                 be_emit_cstring("\t.ascii \"");
 733         } else {
 734                 be_emit_cstring("\t.string \"");
 735                 len -= 1;
 736         }
 737
 738         for (i = 0; i < len; ++i) {
 739                 const ir_initializer_t *sub_initializer
 740                         = get_initializer_compound_value(initializer, i);
 741
 742                 tarval *tv = get_initializer_tarval_value(sub_initializer);
 743                 int     c  = get_tarval_long(tv);
 744
 745                 switch (c) {
 746                 case '"' : be_emit_cstring("\\\""); break;
 747                 case '\n': be_emit_cstring("\\n"); break;
 748                 case '\r': be_emit_cstring("\\r"); break;
 749                 case '\t': be_emit_cstring("\\t"); break;
 750                 case '\\': be_emit_cstring("\\\\"); break;
 751                 default  :
 752                         if (isprint(c))
 753                                 be_emit_char(c);
 754                         else
 755                                 be_emit_irprintf("\\%o", c);
 756                         break;
 757                 }
 758         }
 759         be_emit_cstring("\"\n");
 760         be_emit_write_line();
 761 }
 762
 763 enum normal_or_bitfield_kind {
 764         NORMAL = 0,
 765         TARVAL,
 766         BITFIELD
 767 };
 768
 769 typedef struct {
 770         enum normal_or_bitfield_kind kind;
 771         union {
 772                 ir_node       *value;
 773                 tarval        *tarval;
 774                 unsigned char  bf_val;
 775         } v;
 776 } normal_or_bitfield;
 777
 778 static int is_type_variable_size(ir_type *type)
 779 {
 780         (void) type;
 781         /* TODO */
 782         return 0;
 783 }
 784
 785 static size_t get_initializer_size(const ir_initializer_t *initializer,
 786                                    ir_type *type)
 787 {
 788         switch (get_initializer_kind(initializer)) {
 789         case IR_INITIALIZER_TARVAL:
 790                 assert(get_tarval_mode(get_initializer_tarval_value(initializer)) == get_type_mode(type));
 791                 return get_type_size_bytes(type);
 792         case IR_INITIALIZER_CONST:
 793         case IR_INITIALIZER_NULL:
 794                 return get_type_size_bytes(type);
 795         case IR_INITIALIZER_COMPOUND:
 796                 if (!is_type_variable_size(type)) {
 797                         return get_type_size_bytes(type);
 798                 } else {
 799                         unsigned n_entries
 800                                 = get_initializer_compound_n_entries(initializer);
 801                         unsigned i;
 802                         unsigned initializer_size = get_type_size_bytes(type);
 803                         for (i = 0; i < n_entries; ++i) {
 804                                 ir_entity *entity = get_compound_member(type, i);
 805                                 ir_type   *type   = get_entity_type(entity);
 806
 807                                 const ir_initializer_t *sub_initializer
 808                                         = get_initializer_compound_value(initializer, i);
 809
 810                                 unsigned offset = get_entity_offset(entity);
 811                                 unsigned size   = get_initializer_size(sub_initializer, type);
 812
 813                                 if (offset + size > initializer_size) {
 814                                         initializer_size = offset + size;
 815                                 }
 816                         }
 817                         return initializer_size;
 818                 }
 819         }
 820
 821         panic("found invalid initializer");
 822 }
 823
 824 #ifndef NDEBUG
 825 static normal_or_bitfield *glob_vals;
 826 static size_t              max_vals;
 827 #endif
 828
 829 static void dump_bitfield(normal_or_bitfield *vals, size_t offset_bits,
 830                           const ir_initializer_t *initializer, ir_type *type)
 831 {
 832         unsigned char  last_bits = 0;
 833         ir_mode       *mode      = get_type_mode(type);
 834         tarval        *tv        = NULL;
 835         unsigned char  curr_bits;
 836         int            value_len;
 837         int            j;
 838
 839         switch (get_initializer_kind(initializer)) {
 840         case IR_INITIALIZER_NULL:
 841                 return;
 842         case IR_INITIALIZER_TARVAL:
 843                 tv = get_initializer_tarval_value(initializer);
 844                 break;
 845         case IR_INITIALIZER_CONST: {
 846                 ir_node *node = get_initializer_const_value(initializer);
 847                 if (!is_Const(node)) {
 848                         panic("bitfield initializer not a Const node");
 849                 }
 850                 tv = get_Const_tarval(node);
 851                 break;
 852         }
 853         case IR_INITIALIZER_COMPOUND:
 854                 panic("bitfield initializer is compound");
 855         }
 856         if (tv == NULL) {
 857                 panic("Couldn't get numeric value for bitfield initializer");
 858         }
 859         tv = tarval_convert_to(tv, get_type_mode(type));
 860
 861         /* normalize offset */
 862         vals        += offset_bits >> 3;
 863         offset_bits &= 7;
 864         value_len    = get_mode_size_bits(mode);
 865
 866         /* combine bits with existing bits */
 867         for (j = 0; value_len + (int) offset_bits > 0; ++j) {
 868                 assert((size_t) (vals - glob_vals) + j < max_vals);
 869                 assert(vals[j].kind == BITFIELD ||
 870                                 (vals[j].kind == NORMAL && vals[j].v.value == NULL));
 871                 vals[j].kind = BITFIELD;
 872                 curr_bits    = get_tarval_sub_bits(tv, j);
 873                 vals[j].v.bf_val
 874                         |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
 875                 value_len -= 8;
 876                 last_bits = curr_bits;
 877         }
 878 }
 879
 880 static void dump_ir_initializer(normal_or_bitfield *vals,
 881                                 const ir_initializer_t *initializer,
 882                                 ir_type *type)
 883 {
 884         assert((size_t) (vals - glob_vals) < max_vals);
 885
 886         switch (get_initializer_kind(initializer)) {
 887         case IR_INITIALIZER_NULL:
 888                 return;
 889         case IR_INITIALIZER_TARVAL: {
 890                 size_t i;
 891
 892                 assert(vals->kind != BITFIELD);
 893                 vals->kind     = TARVAL;
 894                 vals->v.tarval = get_initializer_tarval_value(initializer);
 895                 assert(get_type_mode(type) == get_tarval_mode(vals->v.tarval));
 896                 for (i = 1; i < get_type_size_bytes(type); ++i) {
 897                         vals[i].kind    = NORMAL;
 898                         vals[i].v.value = NULL;
 899                 }
 900                 return;
 901         }
 902         case IR_INITIALIZER_CONST: {
 903                 size_t i;
 904
 905                 assert(vals->kind != BITFIELD);
 906                 vals->kind    = NORMAL;
 907                 vals->v.value = get_initializer_const_value(initializer);
 908                 for (i = 1; i < get_type_size_bytes(type); ++i) {
 909                         vals[i].kind    = NORMAL;
 910                         vals[i].v.value = NULL;
 911                 }
 912                 return;
 913         }
 914         case IR_INITIALIZER_COMPOUND: {
 915                 size_t i = 0;
 916                 size_t n = get_initializer_compound_n_entries(initializer);
 917
 918                 if (is_Array_type(type)) {
 919                         ir_type *element_type = get_array_element_type(type);
 920                         size_t   skip         = get_type_size_bytes(element_type);
 921                         size_t   alignment    = get_type_alignment_bytes(element_type);
 922                         size_t   misalign     = skip % alignment;
 923                         if (misalign != 0) {
 924                                 skip += alignment - misalign;
 925                         }
 926
 927                         for (i = 0; i < n; ++i) {
 928                                 ir_initializer_t *sub_initializer
 929                                         = get_initializer_compound_value(initializer, i);
 930
 931                                 dump_ir_initializer(vals, sub_initializer, element_type);
 932
 933                                 vals += skip;
 934                         }
 935                 } else {
 936                         size_t n_members, i;
 937                         assert(is_compound_type(type));
 938                         n_members = get_compound_n_members(type);
 939                         for (i = 0; i < n_members; ++i) {
 940                                 ir_entity        *member    = get_compound_member(type, i);
 941                                 size_t            offset    = get_entity_offset(member);
 942                                 ir_type          *subtype   = get_entity_type(member);
 943                                 ir_mode          *mode      = get_type_mode(subtype);
 944                                 ir_initializer_t *sub_initializer;
 945
 946                                 assert(i < get_initializer_compound_n_entries(initializer));
 947                                 sub_initializer
 948                                         = get_initializer_compound_value(initializer, i);
 949
 950                                 if (mode != NULL) {
 951                                         size_t offset_bits
 952                                                 = get_entity_offset_bits_remainder(member);
 953                                         size_t value_len   = get_mode_size_bits(mode);
 954
 955                                         if (offset_bits != 0 ||
 956                                                 (value_len != 8 && value_len != 16 && value_len != 32
 957                                                  && value_len != 64)) {
 958                                                 dump_bitfield(&vals[offset], offset_bits,
 959                                                               sub_initializer, subtype);
 960                                                 continue;
 961                                         }
 962                                 }
 963
 964                                 dump_ir_initializer(&vals[offset], sub_initializer, subtype);
 965                         }
 966                 }
 967
 968                 return;
 969         }
 970         }
 971         panic("invalid ir_initializer kind found");
 972 }
 973
 974 static void dump_initializer(be_gas_decl_env_t *env, const ir_entity *entity)
 975 {
 976         const ir_initializer_t *initializer = entity->initializer;
 977         ir_type                *type;
 978         normal_or_bitfield     *vals;
 979         size_t                  size;
 980         size_t                  k;
 981
 982         if (initializer_is_string_const(initializer)) {
 983                 dump_string_initializer(initializer);
 984                 return;
 985         }
 986
 987         type = get_entity_type(entity);
 988         size = get_initializer_size(initializer, type);
 989
 990         if (size == 0)
 991                 return;
 992
 993         /*
 994          * In the worst case, every initializer allocates one byte.
 995          * Moreover, initializer might be big, do not allocate on stack.
 996          */
 997         vals = XMALLOCNZ(normal_or_bitfield, size);
 998
 999 #ifndef NDEBUG
1000         glob_vals = vals;
1001         max_vals  = size;
1002 #endif
1003
1004         dump_ir_initializer(vals, initializer, type);
1005
1006         /* now write values sorted */
1007         for (k = 0; k < size; ) {
1008                 int space     = 0;
1009                 int elem_size = 1;
1010                 if (vals[k].kind == NORMAL) {
1011                         if (vals[k].v.value != NULL) {
1012                                 dump_atomic_init(env, vals[k].v.value);
1013                                 elem_size = get_mode_size_bytes(get_irn_mode(vals[k].v.value));
1014                         } else {
1015                                 elem_size = 0;
1016                         }
1017                 } else if (vals[k].kind == TARVAL) {
1018                         tarval *tv   = vals[k].v.tarval;
1019                         size_t  size = get_mode_size_bytes(get_tarval_mode(tv));
1020
1021                         assert(tv != NULL);
1022
1023                         elem_size = size;
1024                         dump_size_type(size);
1025                         dump_arith_tarval(tv, size);
1026                         be_emit_char('\n');
1027                         be_emit_write_line();
1028                 } else {
1029                         assert(vals[k].kind == BITFIELD);
1030                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
1031                         be_emit_write_line();
1032                 }
1033
1034                 k += elem_size;
1035                 while (k < size && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
1036                         ++space;
1037                         ++k;
1038                 }
1039
1040                 /* a gap */
1041                 if (space > 0) {
1042                         be_emit_irprintf("\t.space\t%d\n", space);
1043                         be_emit_write_line();
1044                 }
1045         }
1046         xfree(vals);
1047 }
1048
1049 static void dump_compound_graph_init(be_gas_decl_env_t *env,
1050                                      const ir_entity *ent)
1051 {
1052         normal_or_bitfield *vals;
1053         int i, j, n;
1054         unsigned k, last_ofs;
1055
1056         if (ent_is_string_const(ent)) {
1057                 dump_string_cst(ent);
1058                 return;
1059         }
1060
1061         n = get_compound_ent_n_values(ent);
1062
1063         /* Find the initializer size. Sorrily gcc support a nasty feature:
1064            The last field of a compound may be a flexible array. This allows
1065            initializers bigger than the type size. */
1066         last_ofs = get_type_size_bytes(get_entity_type(ent));
1067         for (i = 0; i < n; ++i) {
1068                 unsigned offset         = get_compound_ent_value_offset_bytes(ent, i);
1069                 unsigned bits_remainder = get_compound_ent_value_offset_bit_remainder(ent, i);
1070                 ir_node  *value         = get_compound_ent_value(ent, i);
1071                 unsigned value_len      = get_mode_size_bits(get_irn_mode(value));
1072
1073                 offset += (value_len + bits_remainder + 7) >> 3;
1074
1075                 if (offset > last_ofs) {
1076                         last_ofs = offset;
1077                 }
1078         }
1079
1080         /*
1081          * In the worst case, every initializer allocates one byte.
1082          * Moreover, initializer might be big, do not allocate on stack.
1083          */
1084         vals = XMALLOCNZ(normal_or_bitfield, last_ofs);
1085
1086         /* collect the values and store them at the offsets */
1087         for (i = 0; i < n; ++i) {
1088                 unsigned offset      = get_compound_ent_value_offset_bytes(ent, i);
1089                 int      offset_bits = get_compound_ent_value_offset_bit_remainder(ent, i);
1090                 ir_node  *value      = get_compound_ent_value(ent, i);
1091                 int      value_len   = get_mode_size_bits(get_irn_mode(value));
1092
1093                 assert(offset_bits >= 0);
1094
1095                 if (offset_bits != 0 ||
1096                                 (value_len != 8 && value_len != 16 && value_len != 32 && value_len != 64)) {
1097                         tarval *tv = get_atomic_init_tv(value);
1098                         unsigned char curr_bits, last_bits = 0;
1099                         if (tv == NULL) {
1100                                 panic("Couldn't get numeric value for bitfield initializer '%s'",
1101                                                 get_entity_ld_name(ent));
1102                         }
1103                         /* normalize offset */
1104                         offset += offset_bits >> 3;
1105                         offset_bits &= 7;
1106
1107                         for (j = 0; value_len + offset_bits > 0; ++j) {
1108                                 assert(offset + j < last_ofs);
1109                                 assert(vals[offset + j].kind == BITFIELD || vals[offset + j].v.value == NULL);
1110                                 vals[offset + j].kind = BITFIELD;
1111                                 curr_bits = get_tarval_sub_bits(tv, j);
1112                                 vals[offset + j].v.bf_val |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
1113                                 value_len -= 8;
1114                                 last_bits = curr_bits;
1115                         }
1116                 } else {
1117                         int i;
1118
1119                         assert(offset < last_ofs);
1120                         assert(vals[offset].kind == NORMAL);
1121                         for (i = 1; i < value_len / 8; ++i) {
1122                                 assert(vals[offset + i].v.value == NULL);
1123                         }
1124                         vals[offset].v.value = value;
1125                 }
1126         }
1127
1128         /* now write them sorted */
1129         for (k = 0; k < last_ofs; ) {
1130                 int space = 0, skip = 0;
1131                 if (vals[k].kind == NORMAL) {
1132                         if (vals[k].v.value != NULL) {
1133                                 dump_atomic_init(env, vals[k].v.value);
1134                                 skip = get_mode_size_bytes(get_irn_mode(vals[k].v.value)) - 1;
1135                         } else {
1136                                 space = 1;
1137                         }
1138                 } else {
1139                         assert(vals[k].kind == BITFIELD);
1140                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
1141                 }
1142
1143                 ++k;
1144                 while (k < last_ofs && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
1145                         ++space;
1146                         ++k;
1147                 }
1148                 space -= skip;
1149                 assert(space >= 0);
1150
1151                 /* a gap */
1152                 if (space > 0) {
1153                         be_emit_irprintf("\t.space\t%d\n", space);
1154                         be_emit_write_line();
1155                 }
1156         }
1157         xfree(vals);
1158 }
1159
1160 static void emit_align(unsigned p2alignment)
1161 {
1162         be_emit_irprintf("\t.p2align\t%u\n", log2_floor(p2alignment));
1163         be_emit_write_line();
1164 }
1165
1166 static unsigned get_effective_entity_alignment(const ir_entity *entity)
1167 {
1168         unsigned alignment = get_entity_alignment(entity);
1169         if (alignment == 0) {
1170                 ir_type *type = get_entity_type(entity);
1171                 alignment     = get_type_alignment_bytes(type);
1172         }
1173         return alignment;
1174 }
1175
1176 static be_gas_section_t determine_section(be_gas_decl_env_t *env,
1177                                           const ir_entity *entity)
1178 {
1179         ir_type *owner = get_entity_owner(entity);
1180
1181         if (owner == get_segment_type(IR_SEGMENT_GLOBAL)) {
1182                 if (is_method_entity(entity))
1183                         return GAS_SECTION_TEXT;
1184
1185                 ir_linkage linkage = get_entity_linkage(entity);
1186                 if (linkage & IR_LINKAGE_CONSTANT) {
1187                         /* mach-o is the only one with a cstring section */
1188                         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O
1189                                         && ent_is_string_const(entity))
1190                                 return GAS_SECTION_CSTRING;
1191
1192                         return GAS_SECTION_RODATA;
1193                 }
1194                 if (entity_is_null(entity))
1195                         return GAS_SECTION_BSS;
1196
1197                 return GAS_SECTION_DATA;
1198         } else if (owner == env->main_env->pic_symbols_type) {
1199                 return GAS_SECTION_PIC_SYMBOLS;
1200         } else if (owner == env->main_env->pic_trampolines_type) {
1201                 return GAS_SECTION_PIC_TRAMPOLINES;
1202         } else if (owner == get_segment_type(IR_SEGMENT_CONSTRUCTORS)) {
1203                 return GAS_SECTION_CONSTRUCTORS;
1204         } else if (owner == get_segment_type(IR_SEGMENT_DESTRUCTORS)) {
1205                 return GAS_SECTION_DESTRUCTORS;
1206         } else if (owner == get_segment_type(IR_SEGMENT_THREAD_LOCAL)) {
1207                 ir_linkage linkage = get_entity_linkage(entity);
1208                 if (linkage & IR_LINKAGE_MERGE) {
1209                         panic("IR_LINKAGE_MERGE not supported for THREAD_LOCAL entities");
1210                 }
1211
1212                 if (entity_is_null(entity)) {
1213                         return GAS_SECTION_TLS_BSS;
1214                 }
1215                 return GAS_SECTION_TLS_DATA;
1216         }
1217
1218         panic("Couldn't determine section for %+F?!?", entity);
1219 }
1220
1221 static void emit_common(const ir_entity *ent)
1222 {
1223         const char *name      = get_entity_ld_name(ent);
1224         unsigned    size      = get_type_size_bytes(get_entity_type(ent));
1225         unsigned    alignment = get_effective_entity_alignment(ent);
1226
1227         switch (be_gas_object_file_format) {
1228         case OBJECT_FILE_FORMAT_MACH_O:
1229                 be_emit_irprintf("\t.comm %s,%u,%u\n", name, size,
1230                                  log2_floor(alignment));
1231                 be_emit_write_line();
1232                 return;
1233         case OBJECT_FILE_FORMAT_ELF:
1234                 be_emit_irprintf("\t.comm %s,%u,%u\n", name, size, alignment);
1235                 be_emit_write_line();
1236                 return;
1237         case OBJECT_FILE_FORMAT_COFF:
1238                 be_emit_irprintf("\t.comm %s,%u # %u\n", name, size, alignment);
1239                 be_emit_write_line();
1240                 return;
1241         }
1242         panic("invalid object file format");
1243 }
1244
1245 static void dump_indirect_symbol(const ir_entity *entity, be_gas_section_t section)
1246 {
1247         /* we can only do PIC code on macho so far */
1248         assert(be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O);
1249
1250         be_emit_ident(get_entity_ld_ident(entity));
1251         be_emit_cstring(":\n");
1252         be_emit_write_line();
1253         be_emit_cstring("\t.indirect_symbol ");
1254         be_emit_ident(get_entity_ident(entity));
1255         be_emit_char('\n');
1256         be_emit_write_line();
1257         if (section == GAS_SECTION_PIC_TRAMPOLINES) {
1258                 be_emit_cstring("\thlt ; hlt ; hlt ; hlt ; hlt\n");
1259                 be_emit_write_line();
1260         } else {
1261                 assert(section == GAS_SECTION_PIC_SYMBOLS);
1262                 be_emit_cstring("\t.long 0\n");
1263                 be_emit_write_line();
1264         }
1265 }
1266
1267 /**
1268  * Dump a global entity.
1269  *
1270  * @param env  the gas output environment
1271  * @param ent  the entity to be dumped
1272  */
1273 static void dump_global(be_gas_decl_env_t *env, const ir_entity *ent)
1274 {
1275         ir_type          *type           = get_entity_type(ent);
1276         ident            *ld_ident       = get_entity_ld_ident(ent);
1277         unsigned          alignment      = get_effective_entity_alignment(ent);
1278         be_gas_section_t  section        = determine_section(env, ent);
1279
1280         /* we already emitted all methods. Except for the trampolines which
1281          * the assembler/linker generates */
1282         if (is_Method_type(type) && section != GAS_SECTION_PIC_TRAMPOLINES) {
1283                 return;
1284         }
1285         /* block labels are already emittet in the code */
1286         if (type == firm_code_type)
1287                 return;
1288
1289         be_dbg_variable(ent);
1290
1291         /* nothing to do for externally defined values */
1292         if (get_entity_visibility(ent) == ir_visibility_external)
1293                 return;
1294
1295         if (!is_po2(alignment))
1296                 panic("alignment not a power of 2");
1297
1298         if (section == GAS_SECTION_BSS &&
1299                         (get_entity_linkage(ent) & IR_LINKAGE_MERGE)) {
1300                 if (get_entity_visibility(ent) != ir_visibility_default) {
1301                         panic("merge link semantic not supported for local/extern entities");
1302                 }
1303                 emit_common(ent);
1304                 return;
1305         }
1306
1307         be_gas_emit_switch_section(section);
1308
1309         if (section == GAS_SECTION_PIC_TRAMPOLINES
1310                         || section == GAS_SECTION_PIC_SYMBOLS) {
1311                 dump_indirect_symbol(ent, section);
1312                 return;
1313         }
1314
1315         /* alignment */
1316         if (alignment > 1) {
1317                 emit_align(alignment);
1318         }
1319         emit_entity_visibility(ent);
1320         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_ELF
1321                         && be_gas_emit_types) {
1322                 be_emit_cstring("\t.type\t");
1323                 be_emit_ident(ld_ident);
1324                 be_emit_cstring(", ");
1325                 be_emit_char(be_gas_elf_type_char);
1326                 be_emit_cstring("object\n\t.size\t");
1327                 be_emit_ident(ld_ident);
1328                 be_emit_irprintf(", %u\n", get_type_size_bytes(type));
1329         }
1330
1331         if (get_id_str(ld_ident)[0] != '\0') {
1332                 be_emit_ident(ld_ident);
1333                 be_emit_cstring(":\n");
1334                 be_emit_write_line();
1335         }
1336
1337         if (section == GAS_SECTION_BSS || section == GAS_SECTION_TLS_BSS) {
1338                 be_emit_irprintf("\t.zero %u\n", get_type_size_bytes(type));
1339                 be_emit_write_line();
1340         } else if(entity_has_compound_ent_values(ent)) {
1341                 dump_compound_graph_init(env, ent);
1342         } else {
1343                 assert(ent->initializer != NULL);
1344                 dump_initializer(env, ent);
1345         }
1346 }
1347
1348 /**
1349  * Dumps declarations of global variables and the initialization code.
1350  *
1351  * @param gt                a global like type, either the global or the TLS one
1352  * @param env               an environment
1353  */
1354 static void be_gas_dump_globals(ir_type *gt, be_gas_decl_env_t *env)
1355 {
1356         int i, n = get_compound_n_members(gt);
1357
1358         for (i = 0; i < n; i++) {
1359                 ir_entity *ent = get_compound_member(gt, i);
1360                 dump_global(env, ent);
1361         }
1362 }
1363
1364 /************************************************************************/
1365
1366 /* Generate all entities. */
1367 void be_gas_emit_decls(const be_main_env_t *main_env)
1368 {
1369         be_gas_decl_env_t env;
1370         memset(&env, 0, sizeof(env));
1371
1372         /* dump global type */
1373         env.main_env = main_env;
1374         env.section  = (be_gas_section_t) -1;
1375
1376         be_gas_dump_globals(get_glob_type(), &env);
1377         be_gas_dump_globals(get_tls_type(), &env);
1378         be_gas_dump_globals(get_segment_type(IR_SEGMENT_CONSTRUCTORS), &env);
1379         be_gas_dump_globals(get_segment_type(IR_SEGMENT_DESTRUCTORS), &env);
1380         be_gas_dump_globals(main_env->pic_symbols_type, &env);
1381         be_gas_dump_globals(main_env->pic_trampolines_type, &env);
1382
1383         /**
1384          * ".subsections_via_symbols marks object files which are OK to divide
1385          * their section contents into individual blocks".
1386          * From my understanding this means no label points in the middle of an
1387          * object which we want to address as a whole. Firm code should be fine
1388          * with this.
1389          */
1390         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
1391                 be_emit_cstring("\t.subsections_via_symbols\n");
1392                 be_emit_write_line();
1393         }
1394 }