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

   1 /*
   2  * Copyright (C) 1995-2011 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  */
  26 #include "config.h"
  27
  28 #include "begnuas.h"
  29
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <ctype.h>
  33 #include <assert.h>
  34
  35 #include "obst.h"
  36 #include "tv.h"
  37 #include "irnode.h"
  38 #include "irprog.h"
  39 #include "entity_t.h"
  40 #include "error.h"
  41 #include "util.h"
  42 #include "execfreq.h"
  43
  44 #include "be_t.h"
  45 #include "beemitter.h"
  46 #include "bedwarf.h"
  47
  48 /** by default, we generate assembler code for the Linux gas */
  49 object_file_format_t  be_gas_object_file_format = OBJECT_FILE_FORMAT_ELF;
  50 elf_variant_t         be_gas_elf_variant        = ELF_VARIANT_NORMAL;
  51 bool                  be_gas_emit_types         = true;
  52 char                  be_gas_elf_type_char      = '@';
  53
  54 static be_gas_section_t current_section = (be_gas_section_t) -1;
  55 static pmap            *block_numbers;
  56 static unsigned         next_block_nr;
  57
  58 /**
  59  * An environment containing all needed dumper data.
  60  * Currently we create the file completely in memory first, then
  61  * write it to the disk. This is an artifact from the old C-generating backend
  62  * and even there NOT needed. So we might change it in the future.
  63  */
  64 typedef struct be_gas_decl_env {
  65         be_gas_section_t     section;
  66         const be_main_env_t *main_env;
  67 } be_gas_decl_env_t;
  68
  69 static void emit_section_macho(be_gas_section_t section)
  70 {
  71         be_gas_section_t  base  = section & GAS_SECTION_TYPE_MASK;
  72         be_gas_section_t  flags = section & ~GAS_SECTION_TYPE_MASK;
  73         const char       *name;
  74
  75         if (current_section == section)
  76                 return;
  77         current_section = section;
  78
  79         /* shortforms */
  80         if (flags == 0) {
  81                 switch (base) {
  82                 case GAS_SECTION_TEXT:            name = "text";          break;
  83                 case GAS_SECTION_DATA:            name = "data";          break;
  84                 case GAS_SECTION_RODATA:          name = "const";         break;
  85                 case GAS_SECTION_BSS:             name = "data";          break;
  86                 case GAS_SECTION_CONSTRUCTORS:    name = "mod_init_func"; break;
  87                 case GAS_SECTION_DESTRUCTORS:     name = "mod_term_func"; break;
  88                 case GAS_SECTION_PIC_TRAMPOLINES: name = "section\t__IMPORT,__jump_table,symbol_stubs,self_modifying_code+pure_instructions,5"; break;
  89                 case GAS_SECTION_PIC_SYMBOLS:     name = "section\t__IMPORT,__pointers,non_lazy_symbol_pointers"; break;
  90                 case GAS_SECTION_CSTRING:         name = "cstring";       break;
  91                 case GAS_SECTION_DEBUG_INFO:      name = "section __DWARF,__debug_info,regular,debug"; break;
  92                 case GAS_SECTION_DEBUG_ABBREV:    name = "section __DWARF,__debug_abbrev,regular,debug"; break;
  93                 case GAS_SECTION_DEBUG_LINE:      name = "section __DWARF,__debug_line,regular,debug"; break;
  94                 case GAS_SECTION_DEBUG_PUBNAMES:  name = "section __DWARF,__debug_pubnames,regular,debug"; break;
  95                 case GAS_SECTION_DEBUG_FRAME:     name = "section __DWARF,__debug_frame,regular,debug"; break;
  96                 default: panic("unsupported scetion type 0x%X", section);
  97                 }
  98                 be_emit_irprintf("\t.%s\n", name);
  99                 be_emit_write_line();
 100         } else if (flags & GAS_SECTION_FLAG_COMDAT) {
 101                 switch (base) {
 102                 case GAS_SECTION_TEXT:            name = "section __TEXT,__textcoal_nt,coalesced,pure_instructions"; break;
 103                 case GAS_SECTION_BSS:
 104                 case GAS_SECTION_DATA:            name = "section __DATA,__datacoal_nt,coalesced"; break;
 105                 case GAS_SECTION_RODATA:          name = "section __TEXT,__const_coal,coalesced"; break;
 106                 case GAS_SECTION_CSTRING:         name = "section __TEXT,__const_coal,coalesced"; break;
 107                 default: panic("unsupported scetion type 0x%X", section);
 108                 }
 109         } else if (flags & GAS_SECTION_FLAG_TLS) {
 110                 panic("thread local storage not supported on macho (section 0x%X)", section);
 111         } else {
 112                 panic("unsupported section type 0x%X", section);
 113         }
 114 }
 115
 116 static void emit_section_sparc(be_gas_section_t section, const ir_entity *entity)
 117 {
 118         be_gas_section_t base = section & GAS_SECTION_TYPE_MASK;
 119         be_gas_section_t flags = section & ~GAS_SECTION_TYPE_MASK;
 120         static const char *const basename[GAS_SECTION_LAST+1] = {
 121                 "text",
 122                 "data",
 123                 "rodata",
 124                 "bss",
 125                 "ctors",
 126                 "dtors",
 127                 NULL, /* cstring */
 128                 NULL, /* pic trampolines */
 129                 NULL, /* pic symbols */
 130                 "debug_info",
 131                 "debug_abbrev",
 132                 "debug_line",
 133                 "debug_pubnames"
 134                 "debug_frame",
 135         };
 136
 137         if (current_section == section && !(section & GAS_SECTION_FLAG_COMDAT))
 138                 return;
 139         current_section = section;
 140
 141         be_emit_cstring("\t.section\t\".");
 142
 143         /* Part1: section-name */
 144         if (flags & GAS_SECTION_FLAG_TLS)
 145                 be_emit_char('t');
 146         assert(base < (be_gas_section_t)ARRAY_SIZE(basename));
 147         be_emit_string(basename[base]);
 148
 149         if (flags & GAS_SECTION_FLAG_COMDAT) {
 150                 be_emit_char('.');
 151                 be_gas_emit_entity(entity);
 152         }
 153         be_emit_char('"');
 154
 155         /* for the simple sections we're done here */
 156         if (flags == 0)
 157                 goto end;
 158
 159         be_emit_cstring(",#alloc");
 160
 161         switch (base) {
 162         case GAS_SECTION_TEXT: be_emit_cstring(",#execinstr"); break;
 163         case GAS_SECTION_DATA:
 164         case GAS_SECTION_BSS:  be_emit_cstring(",#write"); break;
 165         default:
 166                 /* nothing */
 167                 break;
 168         }
 169         if (flags & GAS_SECTION_FLAG_TLS) {
 170                 be_emit_cstring(",#tls");
 171         }
 172
 173 end:
 174         be_emit_char('\n');
 175         be_emit_write_line();
 176 }
 177
 178 static void emit_section(be_gas_section_t section, const ir_entity *entity)
 179 {
 180         be_gas_section_t base = section & GAS_SECTION_TYPE_MASK;
 181         be_gas_section_t flags = section & ~GAS_SECTION_TYPE_MASK;
 182         const char *f;
 183         static const struct {
 184                 const char *name;
 185                 const char *type;
 186                 const char *flags;
 187         } sectioninfos[GAS_SECTION_LAST+1] = {
 188                 { "text",           "progbits", "ax" },
 189                 { "data",           "progbits", "aw" },
 190                 { "rodata",         "progbits", "a"  },
 191                 { "bss",            "nobits",   "aw" },
 192                 { "ctors",          "progbits", "aw" },
 193                 { "dtors",          "progbits", "aw" },
 194                 { NULL,             NULL,       NULL }, /* cstring */
 195                 { NULL,             NULL,       NULL }, /* pic trampolines */
 196                 { NULL,             NULL,       NULL }, /* pic symbols */
 197                 { "debug_info",     "progbits", ""   },
 198                 { "debug_abbrev",   "progbits", ""   },
 199                 { "debug_line",     "progbits", ""   },
 200                 { "debug_pubnames", "progbits", ""   },
 201                 { "debug_frame",    "progbits", ""   },
 202         };
 203
 204         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 205                 emit_section_macho(section);
 206                 return;
 207         } else if(be_gas_elf_variant == ELF_VARIANT_SPARC) {
 208                 emit_section_sparc(section, entity);
 209                 return;
 210         }
 211
 212         if (current_section == section && !(section & GAS_SECTION_FLAG_COMDAT))
 213                 return;
 214         current_section = section;
 215
 216         /* shortforms */
 217         if (flags == 0) {
 218                 switch (base) {
 219                 case GAS_SECTION_TEXT:
 220                         be_emit_cstring("\t.text\n");
 221                         be_emit_write_line();
 222                         return;
 223                 case GAS_SECTION_DATA:
 224                         be_emit_cstring("\t.data\n");
 225                         be_emit_write_line();
 226                         return;
 227                 case GAS_SECTION_RODATA:
 228                         be_emit_cstring("\t.section\t.rodata\n");
 229                         be_emit_write_line();
 230                         return;
 231                 case GAS_SECTION_BSS:
 232                         be_emit_cstring("\t.bss\n");
 233                         be_emit_write_line();
 234                         return;
 235                 default:
 236                         break;
 237                 }
 238         }
 239
 240         assert(base < (be_gas_section_t) ARRAY_SIZE(sectioninfos));
 241         be_emit_cstring("\t.section\t.");
 242         /* section name */
 243         if (flags & GAS_SECTION_FLAG_TLS)
 244                 be_emit_char('t');
 245         be_emit_string(sectioninfos[base].name);
 246         if (flags & GAS_SECTION_FLAG_COMDAT) {
 247                 be_emit_char('.');
 248                 be_gas_emit_entity(entity);
 249         }
 250
 251         /* section flags */
 252         be_emit_cstring(",\"");
 253         for (f = sectioninfos[base].flags; *f != '\0'; ++f) {
 254                 be_emit_char(*f);
 255         }
 256         if (flags & GAS_SECTION_FLAG_TLS)
 257                 be_emit_char('T');
 258         if (flags & GAS_SECTION_FLAG_COMDAT)
 259                 be_emit_char('G');
 260
 261         /* section type */
 262         if (be_gas_object_file_format != OBJECT_FILE_FORMAT_COFF) {
 263                 be_emit_cstring("\",");
 264                 be_emit_char(be_gas_elf_type_char);
 265                 be_emit_string(sectioninfos[base].type);
 266         }
 267
 268         if (flags & GAS_SECTION_FLAG_COMDAT) {
 269                 be_emit_char(',');
 270                 be_gas_emit_entity(entity);
 271                 be_emit_cstring(",comdat");
 272         }
 273         be_emit_char('\n');
 274         be_emit_write_line();
 275 }
 276
 277
 278
 279 void be_gas_emit_switch_section(be_gas_section_t section)
 280 {
 281         /* you have to produce a switch_section call with entity manually
 282          * for comdat sections */
 283         assert( !(section & GAS_SECTION_FLAG_COMDAT));
 284
 285         emit_section(section, NULL);
 286 }
 287
 288 static ir_tarval *get_initializer_tarval(const ir_initializer_t *initializer)
 289 {
 290         if (initializer->kind == IR_INITIALIZER_TARVAL)
 291                 return initializer->tarval.value;
 292         if (initializer->kind == IR_INITIALIZER_CONST) {
 293                 ir_node *node = initializer->consti.value;
 294                 if (is_Const(node)) {
 295                         return get_Const_tarval(node);
 296                 }
 297         }
 298         return get_tarval_undefined();
 299 }
 300
 301 static bool initializer_is_string_const(const ir_initializer_t *initializer)
 302 {
 303         size_t i, len;
 304         bool found_printable = false;
 305
 306         if (initializer->kind != IR_INITIALIZER_COMPOUND)
 307                 return false;
 308
 309         len = initializer->compound.n_initializers;
 310         if (len < 1)
 311                 return false;
 312         for (i = 0; i < len; ++i) {
 313                 int               c;
 314                 ir_tarval        *tv;
 315                 ir_mode          *mode;
 316                 ir_initializer_t *sub_initializer
 317                         = initializer->compound.initializers[i];
 318
 319                 tv = get_initializer_tarval(sub_initializer);
 320                 if (!tarval_is_constant(tv))
 321                         return false;
 322
 323                 mode = get_tarval_mode(tv);
 324                 if (!mode_is_int(mode) || get_mode_size_bits(mode) != 8)
 325                         return false;
 326
 327                 c = get_tarval_long(tv);
 328                 if (isgraph(c) || isspace(c))
 329                         found_printable = true;
 330                 else if (c != 0)
 331                         return false;
 332
 333                 if (i == len - 1 && c != '\0')
 334                         return false;
 335         }
 336
 337         return found_printable;
 338 }
 339
 340 static bool initializer_is_null(const ir_initializer_t *initializer)
 341 {
 342         switch (initializer->kind) {
 343         case IR_INITIALIZER_NULL:
 344                 return true;
 345         case IR_INITIALIZER_TARVAL: {
 346                 ir_tarval *tv = initializer->tarval.value;
 347                 return tarval_is_null(tv);
 348         }
 349         case IR_INITIALIZER_CONST: {
 350                 ir_node *value = initializer->consti.value;
 351                 if (!is_Const(value))
 352                         return false;
 353                 return is_Const_null(value);
 354         }
 355         case IR_INITIALIZER_COMPOUND: {
 356                 size_t i;
 357                 for (i = 0; i < initializer->compound.n_initializers; ++i) {
 358                         ir_initializer_t *subinitializer
 359                                 = initializer->compound.initializers[i];
 360                         if (!initializer_is_null(subinitializer))
 361                                 return false;
 362                 }
 363                 return true;
 364         }
 365         }
 366         panic("invalid initializer in initializer_is_null");
 367 }
 368
 369 /**
 370  * Determine if an entity is a string constant
 371  * @param ent The entity
 372  * @return 1 if it is a string constant, 0 otherwise
 373  */
 374 static int entity_is_string_const(const ir_entity *ent)
 375 {
 376         ir_type *type, *element_type;
 377         ir_mode *mode;
 378
 379         type = get_entity_type(ent);
 380
 381         /* if it's an array */
 382         if (!is_Array_type(type))
 383                 return 0;
 384
 385         element_type = get_array_element_type(type);
 386
 387         /* and the array's element type is primitive */
 388         if (!is_Primitive_type(element_type))
 389                 return 0;
 390
 391         /* and the mode of the element type is an int of
 392          * the same size as the byte mode */
 393         mode = get_type_mode(element_type);
 394         if (!mode_is_int(mode) || get_mode_size_bits(mode) != 8)
 395                 return 0;
 396
 397         if (ent->initializer != NULL) {
 398                 return initializer_is_string_const(ent->initializer);
 399         }
 400
 401         return 0;
 402 }
 403
 404 static bool entity_is_null(const ir_entity *entity)
 405 {
 406         ir_initializer_t *initializer = get_entity_initializer(entity);
 407         return initializer == NULL || initializer_is_null(initializer);
 408 }
 409
 410 static bool is_comdat(const ir_entity *entity)
 411 {
 412         ir_linkage linkage = get_entity_linkage(entity);
 413         return (linkage & IR_LINKAGE_MERGE)
 414                 && (linkage & IR_LINKAGE_GARBAGE_COLLECT);
 415 }
 416
 417 static be_gas_section_t determine_basic_section(const ir_entity *entity)
 418 {
 419         ir_linkage linkage;
 420
 421         if (is_method_entity(entity))
 422                 return GAS_SECTION_TEXT;
 423
 424         linkage = get_entity_linkage(entity);
 425         if (linkage & IR_LINKAGE_CONSTANT) {
 426                 /* mach-o is the only one with a cstring section */
 427                 if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O
 428                     && entity_is_string_const(entity))
 429                         return GAS_SECTION_CSTRING;
 430
 431                 return GAS_SECTION_RODATA;
 432         }
 433         if (entity_is_null(entity))
 434                 return GAS_SECTION_BSS;
 435
 436         return GAS_SECTION_DATA;
 437 }
 438
 439 static be_gas_section_t determine_section(be_gas_decl_env_t *env,
 440                                           const ir_entity *entity)
 441 {
 442         ir_type *owner = get_entity_owner(entity);
 443
 444         if (owner == get_segment_type(IR_SEGMENT_GLOBAL)) {
 445                 be_gas_section_t section = determine_basic_section(entity);
 446                 if (is_comdat(entity))
 447                         section |= GAS_SECTION_FLAG_COMDAT;
 448                 return section;
 449         } else if (env != NULL && owner == env->main_env->pic_symbols_type) {
 450                 return GAS_SECTION_PIC_SYMBOLS;
 451         } else if (env != NULL && owner == env->main_env->pic_trampolines_type) {
 452                 return GAS_SECTION_PIC_TRAMPOLINES;
 453         } else if (owner == get_segment_type(IR_SEGMENT_CONSTRUCTORS)) {
 454                 return GAS_SECTION_CONSTRUCTORS;
 455         } else if (owner == get_segment_type(IR_SEGMENT_DESTRUCTORS)) {
 456                 return GAS_SECTION_DESTRUCTORS;
 457         } else if (owner == get_segment_type(IR_SEGMENT_THREAD_LOCAL)) {
 458                 be_gas_section_t section = determine_basic_section(entity);
 459                 if (is_comdat(entity))
 460                         section |= GAS_SECTION_FLAG_COMDAT;
 461
 462                 return section | GAS_SECTION_FLAG_TLS;
 463         }
 464
 465         /* the java frontend keeps some functions inside classes */
 466         if (is_Class_type(owner)) {
 467                 return determine_basic_section(entity);
 468         }
 469
 470         panic("Couldn't determine section for %+F?!?", entity);
 471 }
 472
 473 static void emit_weak(const ir_entity *entity)
 474 {
 475         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 476                 be_emit_cstring("\t.weak_reference ");
 477         } else {
 478                 be_emit_cstring("\t.weak ");
 479         }
 480         be_gas_emit_entity(entity);
 481         be_emit_char('\n');
 482         be_emit_write_line();
 483 }
 484
 485 static void emit_visibility(const ir_entity *entity)
 486 {
 487         ir_linkage const linkage = get_entity_linkage(entity);
 488
 489         if (linkage & IR_LINKAGE_WEAK) {
 490                 emit_weak(entity);
 491                 /* Note: .weak seems to imply .globl so no need to output .globl */
 492         } else if (get_entity_visibility(entity) == ir_visibility_external
 493                    && entity_has_definition(entity)) {
 494                 be_emit_cstring("\t.globl ");
 495                 be_gas_emit_entity(entity);
 496                 be_emit_char('\n');
 497                 be_emit_write_line();
 498         }
 499
 500         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O
 501                         && (linkage & IR_LINKAGE_HIDDEN_USER)
 502                         && get_entity_ld_name(entity)[0] != '\0') {
 503                 be_emit_cstring("\t.no_dead_strip ");
 504                 be_gas_emit_entity(entity);
 505                 be_emit_char('\n');
 506                 be_emit_write_line();
 507         }
 508 }
 509
 510 void be_gas_emit_function_prolog(const ir_entity *entity, unsigned po2alignment, const parameter_dbg_info_t *parameter_infos)
 511 {
 512         be_gas_section_t section;
 513
 514         be_dwarf_method_before(entity, parameter_infos);
 515
 516         section = determine_section(NULL, entity);
 517         emit_section(section, entity);
 518
 519         /* write the begin line (makes the life easier for scripts parsing the
 520          * assembler) */
 521         if (be_options.verbose_asm) {
 522                 be_emit_cstring("# -- Begin  ");
 523                 be_gas_emit_entity(entity);
 524                 be_emit_char('\n');
 525                 be_emit_write_line();
 526         }
 527
 528         if (po2alignment > 0) {
 529                 const char *fill_byte = "";
 530                 unsigned    maximum_skip = (1 << po2alignment) - 1;
 531                 /* gcc fills space between function with 0x90... */
 532                 if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 533                         fill_byte = "0x90";
 534                 }
 535                 be_emit_cstring("\t.p2align ");
 536                 be_emit_irprintf("%u,%s,%u\n", po2alignment, fill_byte, maximum_skip);
 537                 be_emit_write_line();
 538         }
 539         emit_visibility(entity);
 540
 541         switch (be_gas_object_file_format) {
 542         case OBJECT_FILE_FORMAT_ELF:
 543                 be_emit_cstring("\t.type\t");
 544                 be_gas_emit_entity(entity);
 545                 be_emit_cstring(", ");
 546                 be_emit_char(be_gas_elf_type_char);
 547                 be_emit_cstring("function\n");
 548                 be_emit_write_line();
 549                 break;
 550         case OBJECT_FILE_FORMAT_COFF:
 551                 be_emit_cstring("\t.def\t");
 552                 be_gas_emit_entity(entity);
 553                 be_emit_cstring(";");
 554                 if (get_entity_visibility(entity) == ir_visibility_local) {
 555                         be_emit_cstring("\t.scl\t3;");
 556                 } else {
 557                         be_emit_cstring("\t.scl\t2;");
 558                 }
 559                 be_emit_cstring("\t.type\t32;\t.endef\n");
 560                 be_emit_write_line();
 561                 break;
 562         case OBJECT_FILE_FORMAT_MACH_O:
 563                 break;
 564         }
 565         be_gas_emit_entity(entity);
 566         be_emit_cstring(":\n");
 567         be_emit_write_line();
 568
 569         be_dwarf_method_begin();
 570 }
 571
 572 void be_gas_emit_function_epilog(const ir_entity *entity)
 573 {
 574         be_dwarf_method_end();
 575
 576         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_ELF) {
 577                 be_emit_cstring("\t.size\t");
 578                 be_gas_emit_entity(entity);
 579                 be_emit_cstring(", .-");
 580                 be_gas_emit_entity(entity);
 581                 be_emit_char('\n');
 582                 be_emit_write_line();
 583         }
 584
 585         if (be_options.verbose_asm) {
 586                 be_emit_cstring("# -- End  ");
 587                 be_gas_emit_entity(entity);
 588                 be_emit_char('\n');
 589                 be_emit_write_line();
 590         }
 591
 592         be_emit_char('\n');
 593         be_emit_write_line();
 594
 595         next_block_nr += 199;
 596         next_block_nr = next_block_nr/100*100;
 597 }
 598
 599 /**
 600  * Output a tarval.
 601  *
 602  * @param tv     the tarval
 603  * @param bytes  the width of the tarvals value in bytes
 604  */
 605 static void emit_arith_tarval(ir_tarval *tv, unsigned bytes)
 606 {
 607         switch (bytes) {
 608         case 1:
 609                 be_emit_irprintf("0x%02x", get_tarval_sub_bits(tv, 0));
 610                 return;
 611
 612         case 2:
 613                 be_emit_irprintf("0x%02x%02x",
 614                         get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 615                 return;
 616
 617         case 4:
 618                 be_emit_irprintf("0x%02x%02x%02x%02x",
 619                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2),
 620                         get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 621                 return;
 622
 623         case 8:
 624                 be_emit_irprintf("0x%02x%02x%02x%02x%02x%02x%02x%02x",
 625                         get_tarval_sub_bits(tv, 7), get_tarval_sub_bits(tv, 6),
 626                         get_tarval_sub_bits(tv, 5), get_tarval_sub_bits(tv, 4),
 627                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2),
 628                         get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 629                 return;
 630         }
 631
 632         panic("Can't dump a tarval with %d bytes", bytes);
 633 }
 634
 635 /**
 636  * Return the label prefix for labeled instructions.
 637  */
 638 const char *be_gas_insn_label_prefix(void)
 639 {
 640         return ".LE";
 641 }
 642
 643 /**
 644  * Dump an atomic value.
 645  *
 646  * @param env   the gas output environment
 647  * @param init  a node representing the atomic value (on the const code irg)
 648  */
 649 static void emit_init_expression(be_gas_decl_env_t *env, ir_node *init)
 650 {
 651         ir_mode *mode = get_irn_mode(init);
 652         int bytes     = get_mode_size_bytes(mode);
 653         ir_tarval *tv;
 654         ir_entity *ent;
 655
 656         init = skip_Id(init);
 657
 658         switch (get_irn_opcode(init)) {
 659         case iro_Cast:
 660                 emit_init_expression(env, get_Cast_op(init));
 661                 return;
 662
 663         case iro_Conv:
 664                 emit_init_expression(env, get_Conv_op(init));
 665                 return;
 666
 667         case iro_Const:
 668                 tv = get_Const_tarval(init);
 669
 670                 /* it's an arithmetic value */
 671                 emit_arith_tarval(tv, bytes);
 672                 return;
 673
 674         case iro_SymConst:
 675                 switch (get_SymConst_kind(init)) {
 676                 case symconst_addr_ent:
 677                         ent = get_SymConst_entity(init);
 678                         be_gas_emit_entity(ent);
 679                         break;
 680
 681                 case symconst_ofs_ent:
 682                         ent = get_SymConst_entity(init);
 683                         be_emit_irprintf("%d", get_entity_offset(ent));
 684                         break;
 685
 686                 case symconst_type_size:
 687                         be_emit_irprintf("%u", get_type_size_bytes(get_SymConst_type(init)));
 688                         break;
 689
 690                 case symconst_type_align:
 691                         be_emit_irprintf("%u", get_type_alignment_bytes(get_SymConst_type(init)));
 692                         break;
 693
 694                 case symconst_enum_const:
 695                         tv = get_enumeration_value(get_SymConst_enum(init));
 696                         emit_arith_tarval(tv, bytes);
 697                         break;
 698
 699                 default:
 700                         assert(!"emit_atomic_init(): don't know how to init from this SymConst");
 701                 }
 702                 return;
 703
 704         case iro_Add:
 705                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 706                         panic("Constant must be int or pointer for '+' to work");
 707                 }
 708                 emit_init_expression(env, get_Add_left(init));
 709                 be_emit_cstring(" + ");
 710                 emit_init_expression(env, get_Add_right(init));
 711                 return;
 712
 713         case iro_Sub:
 714                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 715                         panic("Constant must be int or pointer for '-' to work");
 716                 }
 717                 emit_init_expression(env, get_Sub_left(init));
 718                 be_emit_cstring(" - ");
 719                 emit_init_expression(env, get_Sub_right(init));
 720                 return;
 721
 722         case iro_Mul:
 723                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 724                         panic("Constant must be int or pointer for '*' to work");
 725                 }
 726                 emit_init_expression(env, get_Mul_left(init));
 727                 be_emit_cstring(" * ");
 728                 emit_init_expression(env, get_Mul_right(init));
 729                 return;
 730
 731         case iro_Unknown:
 732                 be_emit_cstring("0");
 733                 return;
 734
 735         default:
 736                 panic("unsupported IR-node %+F", init);
 737         }
 738 }
 739
 740 /**
 741  * Dumps the type for given size (.byte, .long, ...)
 742  *
 743  * @param size  the size in bytes
 744  */
 745 static void emit_size_type(size_t size)
 746 {
 747         switch (size) {
 748         case 1: be_emit_cstring("\t.byte\t");  break;
 749         case 2: be_emit_cstring("\t.short\t"); break;
 750         case 4: be_emit_cstring("\t.long\t");  break;
 751         case 8: be_emit_cstring("\t.quad\t");  break;
 752
 753         default:
 754                 panic("Try to dump a type with %u bytes", (unsigned)size);
 755         }
 756 }
 757
 758 static size_t emit_string_initializer(const ir_initializer_t *initializer)
 759 {
 760         size_t i, len;
 761
 762         len = initializer->compound.n_initializers;
 763         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 764                 be_emit_cstring("\t.ascii \"");
 765         } else {
 766                 be_emit_cstring("\t.string \"");
 767                 len -= 1;
 768         }
 769
 770         for (i = 0; i < len; ++i) {
 771                 const ir_initializer_t *sub_initializer
 772                         = get_initializer_compound_value(initializer, i);
 773
 774                 ir_tarval *tv = get_initializer_tarval(sub_initializer);
 775                 int        c  = get_tarval_long(tv);
 776
 777                 switch (c) {
 778                 case '"' : be_emit_cstring("\\\""); break;
 779                 case '\n': be_emit_cstring("\\n"); break;
 780                 case '\r': be_emit_cstring("\\r"); break;
 781                 case '\t': be_emit_cstring("\\t"); break;
 782                 case '\\': be_emit_cstring("\\\\"); break;
 783                 default  :
 784                         if (isprint(c))
 785                                 be_emit_char(c);
 786                         else
 787                                 be_emit_irprintf("\\%03o", c);
 788                         break;
 789                 }
 790         }
 791         be_emit_cstring("\"\n");
 792         be_emit_write_line();
 793
 794         return initializer->compound.n_initializers;
 795 }
 796
 797 typedef enum normal_or_bitfield_kind {
 798         NORMAL = 0,
 799         TARVAL,
 800         STRING,
 801         BITFIELD
 802 } normal_or_bitfield_kind;
 803
 804 typedef struct {
 805         normal_or_bitfield_kind kind;
 806         ir_type                *type;
 807         union {
 808                 ir_node                *value;
 809                 ir_tarval              *tarval;
 810                 unsigned char           bf_val;
 811                 const ir_initializer_t *string;
 812         } v;
 813 } normal_or_bitfield;
 814
 815 static size_t get_initializer_size(const ir_initializer_t *initializer,
 816                                    ir_type *type)
 817 {
 818         switch (get_initializer_kind(initializer)) {
 819         case IR_INITIALIZER_TARVAL:
 820                 assert(get_tarval_mode(get_initializer_tarval_value(initializer)) == get_type_mode(type));
 821                 return get_type_size_bytes(type);
 822         case IR_INITIALIZER_CONST:
 823         case IR_INITIALIZER_NULL:
 824                 return get_type_size_bytes(type);
 825         case IR_INITIALIZER_COMPOUND:
 826                 if (is_Array_type(type)) {
 827                         if (is_array_variable_size(type)) {
 828                                 ir_type   *element_type = get_array_element_type(type);
 829                                 unsigned   element_size = get_type_size_bytes(element_type);
 830                                 unsigned   element_align
 831                                         = get_type_alignment_bytes(element_type);
 832                                 unsigned   misalign     = element_size % element_align;
 833                                 size_t     n_inits
 834                                         = get_initializer_compound_n_entries(initializer);
 835                                 element_size += element_align - misalign;
 836                                 return n_inits * element_size;
 837                         } else {
 838                                 return get_type_size_bytes(type);
 839                         }
 840                 } else {
 841                         assert(is_compound_type(type));
 842                         size_t size = get_type_size_bytes(type);
 843                         if (is_compound_variable_size(type)) {
 844                                 /* last initializer has to be an array of variable size */
 845                                 size_t l = get_initializer_compound_n_entries(initializer)-1;
 846                                 const ir_initializer_t *last
 847                                         = get_initializer_compound_value(initializer, l);
 848                                 const ir_entity *last_ent  = get_compound_member(type, l);
 849                                 ir_type         *last_type = get_entity_type(last_ent);
 850                                 assert(is_array_variable_size(last_type));
 851                                 size += get_initializer_size(last, last_type);
 852                         }
 853                         return size;
 854                 }
 855         }
 856
 857         panic("found invalid initializer");
 858 }
 859
 860 #ifndef NDEBUG
 861 static normal_or_bitfield *glob_vals;
 862 static size_t              max_vals;
 863 #endif
 864
 865 static void emit_bitfield(normal_or_bitfield *vals, size_t offset_bits,
 866                           const ir_initializer_t *initializer, ir_type *type)
 867 {
 868         static const size_t BITS_PER_BYTE = 8;
 869         ir_mode   *mode      = get_type_mode(type);
 870         ir_tarval *tv        = NULL;
 871         int        value_len;
 872         size_t     bit_offset;
 873         size_t     end;
 874         bool       big_endian = be_get_backend_param()->byte_order_big_endian;
 875
 876         switch (get_initializer_kind(initializer)) {
 877         case IR_INITIALIZER_NULL:
 878                 return;
 879         case IR_INITIALIZER_TARVAL:
 880                 tv = get_initializer_tarval_value(initializer);
 881                 break;
 882         case IR_INITIALIZER_CONST: {
 883                 ir_node *node = get_initializer_const_value(initializer);
 884                 if (!is_Const(node)) {
 885                         panic("bitfield initializer not a Const node");
 886                 }
 887                 tv = get_Const_tarval(node);
 888                 break;
 889         }
 890         case IR_INITIALIZER_COMPOUND:
 891                 panic("bitfield initializer is compound");
 892         }
 893         if (tv == NULL) {
 894                 panic("Couldn't get numeric value for bitfield initializer");
 895         }
 896         tv = tarval_convert_to(tv, get_type_mode(type));
 897
 898         value_len  = get_type_size_bytes(get_primitive_base_type(type));
 899         bit_offset = 0;
 900         end        = get_mode_size_bits(mode);
 901         while (bit_offset < end) {
 902                 size_t        src_offset      = bit_offset / BITS_PER_BYTE;
 903                 size_t        src_offset_bits = bit_offset % BITS_PER_BYTE;
 904                 size_t        dst_offset      = (bit_offset+offset_bits) / BITS_PER_BYTE;
 905                 size_t        dst_offset_bits = (bit_offset+offset_bits) % BITS_PER_BYTE;
 906                 size_t        src_bits_len    = end-bit_offset;
 907                 size_t        dst_bits_len    = BITS_PER_BYTE-dst_offset_bits;
 908                 unsigned char curr_bits;
 909                 normal_or_bitfield *val;
 910                 if (src_bits_len > dst_bits_len)
 911                         src_bits_len = dst_bits_len;
 912
 913                 if (big_endian) {
 914                         val = &vals[value_len - dst_offset - 1];
 915                 } else {
 916                         val = &vals[dst_offset];
 917                 }
 918
 919                 assert((val-glob_vals) < (ptrdiff_t) max_vals);
 920                 assert(val->kind == BITFIELD ||
 921                                 (val->kind == NORMAL && val->v.value == NULL));
 922                 val->kind  = BITFIELD;
 923                 curr_bits  = get_tarval_sub_bits(tv, src_offset);
 924                 curr_bits  = curr_bits >> src_offset_bits;
 925                 if (src_offset_bits + src_bits_len > 8) {
 926                         unsigned next_bits = get_tarval_sub_bits(tv, src_offset+1);
 927                         curr_bits |= next_bits << (8 - src_offset_bits);
 928                 }
 929                 curr_bits &= (1 << src_bits_len) - 1;
 930                 val->v.bf_val |= curr_bits << dst_offset_bits;
 931
 932                 bit_offset += dst_bits_len;
 933         }
 934 }
 935
 936 static void emit_ir_initializer(normal_or_bitfield *vals,
 937                                 const ir_initializer_t *initializer,
 938                                 ir_type *type)
 939 {
 940         assert((size_t) (vals - glob_vals) < max_vals);
 941
 942         if (initializer_is_string_const(initializer)) {
 943                 assert(vals->kind != BITFIELD);
 944                 vals->kind     = STRING;
 945                 vals->v.string = initializer;
 946                 return;
 947         }
 948
 949         switch (get_initializer_kind(initializer)) {
 950         case IR_INITIALIZER_NULL:
 951                 return;
 952         case IR_INITIALIZER_TARVAL: {
 953                 size_t i;
 954
 955                 assert(vals->kind != BITFIELD);
 956                 vals->kind     = TARVAL;
 957                 vals->type     = type;
 958                 vals->v.tarval = get_initializer_tarval_value(initializer);
 959                 assert(get_type_mode(type) == get_tarval_mode(vals->v.tarval));
 960                 for (i = 1; i < get_type_size_bytes(type); ++i) {
 961                         vals[i].kind    = NORMAL;
 962                         vals[i].type    = NULL;
 963                         vals[i].v.value = NULL;
 964                 }
 965                 return;
 966         }
 967         case IR_INITIALIZER_CONST: {
 968                 size_t i;
 969
 970                 assert(vals->kind != BITFIELD);
 971                 vals->kind    = NORMAL;
 972                 vals->type    = type;
 973                 vals->v.value = get_initializer_const_value(initializer);
 974                 for (i = 1; i < get_type_size_bytes(type); ++i) {
 975                         vals[i].kind    = NORMAL;
 976                         vals[i].type    = NULL;
 977                         vals[i].v.value = NULL;
 978                 }
 979                 return;
 980         }
 981         case IR_INITIALIZER_COMPOUND: {
 982                 size_t i = 0;
 983                 size_t n = get_initializer_compound_n_entries(initializer);
 984
 985                 if (is_Array_type(type)) {
 986                         ir_type *element_type = get_array_element_type(type);
 987                         size_t   skip         = get_type_size_bytes(element_type);
 988                         size_t   alignment    = get_type_alignment_bytes(element_type);
 989                         size_t   misalign     = skip % alignment;
 990                         if (misalign != 0) {
 991                                 skip += alignment - misalign;
 992                         }
 993
 994                         for (i = 0; i < n; ++i) {
 995                                 ir_initializer_t *sub_initializer
 996                                         = get_initializer_compound_value(initializer, i);
 997
 998                                 emit_ir_initializer(vals, sub_initializer, element_type);
 999
1000                                 vals += skip;
1001                         }
1002                 } else {
1003                         size_t n_members, i;
1004                         assert(is_compound_type(type));
1005                         n_members = get_compound_n_members(type);
1006                         for (i = 0; i < n_members; ++i) {
1007                                 ir_entity        *member    = get_compound_member(type, i);
1008                                 size_t            offset    = get_entity_offset(member);
1009                                 ir_type          *subtype   = get_entity_type(member);
1010                                 ir_mode          *mode      = get_type_mode(subtype);
1011                                 ir_initializer_t *sub_initializer;
1012
1013                                 assert(i < get_initializer_compound_n_entries(initializer));
1014                                 sub_initializer
1015                                         = get_initializer_compound_value(initializer, i);
1016
1017                                 if (mode != NULL) {
1018                                         size_t offset_bits
1019                                                 = get_entity_offset_bits_remainder(member);
1020
1021                                         if (is_Primitive_type(subtype)
1022                                                         && get_primitive_base_type(subtype) != NULL) {
1023                                                 emit_bitfield(&vals[offset], offset_bits,
1024                                                               sub_initializer, subtype);
1025                                                 continue;
1026                                         } else {
1027                                                 assert(offset_bits == 0);
1028                                         }
1029                                 }
1030
1031                                 emit_ir_initializer(&vals[offset], sub_initializer, subtype);
1032                         }
1033                 }
1034
1035                 return;
1036         }
1037         }
1038         panic("invalid ir_initializer kind found");
1039 }
1040
1041 static void emit_tarval_data(ir_type *type, ir_tarval *tv)
1042 {
1043         size_t size = get_type_size_bytes(type);
1044         if (size == 12) {
1045                 /* this should be an x86 extended float */
1046                 assert(be_get_backend_param()->byte_order_big_endian == 0);
1047
1048                 /* Beware: Mixed endian output!  One little endian number emitted as
1049                  * three longs.  Each long initializer is written in big endian. */
1050                 be_emit_irprintf(
1051                         "\t.long\t0x%02x%02x%02x%02x\n"
1052                         "\t.long\t0x%02x%02x%02x%02x\n"
1053                         "\t.long\t0x%02x%02x%02x%02x\n",
1054                         get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
1055                         get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0),
1056                         get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
1057                         get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
1058                         get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
1059                         get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8)
1060                 );
1061                 be_emit_write_line();
1062         } else if (size == 16) {
1063                 if (be_get_backend_param()->byte_order_big_endian) {
1064                         be_emit_irprintf(
1065                                 "\t.long\t0x%02x%02x%02x%02x\n"
1066                                 "\t.long\t0x%02x%02x%02x%02x\n"
1067                                 "\t.long\t0x%02x%02x%02x%02x\n"
1068                                 "\t.long\t0x%02x%02x%02x%02x\n",
1069                                 get_tarval_sub_bits(tv, 15), get_tarval_sub_bits(tv, 14),
1070                                 get_tarval_sub_bits(tv, 13), get_tarval_sub_bits(tv, 12),
1071                                 get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
1072                                 get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8),
1073                                 get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
1074                                 get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
1075                                 get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
1076                                 get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0)
1077                         );
1078                 } else {
1079                         /* Beware: Mixed endian output! One little endian number emitted as
1080                          * three longs.  Each long initializer is written in big endian. */
1081                         be_emit_irprintf(
1082                                 "\t.long\t0x%02x%02x%02x%02x\n"
1083                                 "\t.long\t0x%02x%02x%02x%02x\n"
1084                                 "\t.long\t0x%02x%02x%02x%02x\n"
1085                                 "\t.long\t0x%02x%02x%02x%02x\n",
1086                                 get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
1087                                 get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0),
1088                                 get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
1089                                 get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
1090                                 get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
1091                                 get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8),
1092                                 get_tarval_sub_bits(tv, 15), get_tarval_sub_bits(tv, 14),
1093                                 get_tarval_sub_bits(tv, 13), get_tarval_sub_bits(tv, 12)
1094                         );
1095                 }
1096                 be_emit_write_line();
1097                 return;
1098         } else {
1099                 /* default case */
1100                 emit_size_type(size);
1101                 emit_arith_tarval(tv, size);
1102                 be_emit_char('\n');
1103                 be_emit_write_line();
1104         }
1105 }
1106
1107 /**
1108  * Emit an atomic value.
1109  *
1110  * @param env   the gas output environment
1111  * @param init  a node representing the atomic value (on the const code irg)
1112  */
1113 static void emit_node_data(be_gas_decl_env_t *env, ir_node *init, ir_type *type)
1114 {
1115         size_t size = get_type_size_bytes(type);
1116         if (size == 12 || size == 16) {
1117                 ir_tarval *tv;
1118                 if (!is_Const(init)) {
1119                         panic("12/16byte initializers only support Const nodes yet");
1120                 }
1121                 tv = get_Const_tarval(init);
1122                 emit_tarval_data(type, tv);
1123                 return;
1124         }
1125
1126         emit_size_type(size);
1127         emit_init_expression(env, init);
1128         be_emit_char('\n');
1129         be_emit_write_line();
1130 }
1131
1132 static void emit_initializer(be_gas_decl_env_t *env, const ir_entity *entity)
1133 {
1134         const ir_initializer_t *initializer = entity->initializer;
1135         ir_type                *type;
1136         normal_or_bitfield     *vals;
1137         size_t                  size;
1138         size_t                  k;
1139
1140         if (initializer_is_string_const(initializer)) {
1141                 emit_string_initializer(initializer);
1142                 return;
1143         }
1144
1145         type = get_entity_type(entity);
1146         size = get_initializer_size(initializer, type);
1147
1148         if (size == 0)
1149                 return;
1150
1151         /*
1152          * In the worst case, every initializer allocates one byte.
1153          * Moreover, initializer might be big, do not allocate on stack.
1154          */
1155         vals = XMALLOCNZ(normal_or_bitfield, size);
1156
1157 #ifndef NDEBUG
1158         glob_vals = vals;
1159         max_vals  = size;
1160 #endif
1161
1162         emit_ir_initializer(vals, initializer, type);
1163
1164         /* now write values sorted */
1165         for (k = 0; k < size; ) {
1166                 int                     space     = 0;
1167                 normal_or_bitfield_kind kind      = vals[k].kind;
1168                 int                     elem_size;
1169                 switch (kind) {
1170                 case NORMAL:
1171                         if (vals[k].v.value != NULL) {
1172                                 emit_node_data(env, vals[k].v.value, vals[k].type);
1173                                 elem_size = get_type_size_bytes(vals[k].type);
1174                         } else {
1175                                 elem_size = 0;
1176                         }
1177                         break;
1178                 case TARVAL:
1179                         emit_tarval_data(vals[k].type, vals[k].v.tarval);
1180                         elem_size = get_type_size_bytes(vals[k].type);
1181                         break;
1182                 case STRING:
1183                         elem_size = emit_string_initializer(vals[k].v.string);
1184                         break;
1185                 case BITFIELD:
1186                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
1187                         be_emit_write_line();
1188                         elem_size = 1;
1189                         break;
1190                 default:
1191                         panic("internal compiler error (invalid normal_or_bitfield_kind");
1192                 }
1193
1194                 k += elem_size;
1195                 while (k < size && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
1196                         ++space;
1197                         ++k;
1198                 }
1199
1200                 /* a gap */
1201                 if (space > 0) {
1202                         be_emit_irprintf("\t.space\t%d, 0\n", space);
1203                         be_emit_write_line();
1204                 }
1205         }
1206         xfree(vals);
1207 }
1208
1209 static void emit_align(unsigned p2alignment)
1210 {
1211         be_emit_irprintf("\t.p2align\t%u\n", log2_floor(p2alignment));
1212         be_emit_write_line();
1213 }
1214
1215 static unsigned get_effective_entity_alignment(const ir_entity *entity)
1216 {
1217         unsigned alignment = get_entity_alignment(entity);
1218         if (alignment == 0) {
1219                 ir_type *type = get_entity_type(entity);
1220                 alignment     = get_type_alignment_bytes(type);
1221         }
1222         return alignment;
1223 }
1224
1225 static void emit_common(const ir_entity *entity)
1226 {
1227         unsigned size      = get_type_size_bytes(get_entity_type(entity));
1228         unsigned alignment = get_effective_entity_alignment(entity);
1229
1230         if (get_entity_linkage(entity) & IR_LINKAGE_WEAK) {
1231                 emit_weak(entity);
1232         }
1233
1234         switch (be_gas_object_file_format) {
1235         case OBJECT_FILE_FORMAT_MACH_O:
1236                 be_emit_cstring("\t.comm ");
1237                 be_gas_emit_entity(entity);
1238                 be_emit_irprintf(",%u,%u\n", size, log2_floor(alignment));
1239                 be_emit_write_line();
1240                 return;
1241         case OBJECT_FILE_FORMAT_ELF:
1242                 be_emit_cstring("\t.comm ");
1243                 be_gas_emit_entity(entity);
1244                 be_emit_irprintf(",%u,%u\n", size, alignment);
1245                 be_emit_write_line();
1246                 return;
1247         case OBJECT_FILE_FORMAT_COFF:
1248                 be_emit_cstring("\t.comm ");
1249                 be_gas_emit_entity(entity);
1250                 be_emit_irprintf(",%u # %u\n", size, alignment);
1251                 be_emit_write_line();
1252                 return;
1253         }
1254         panic("invalid object file format");
1255 }
1256
1257 static void emit_local_common(const ir_entity *entity)
1258 {
1259         unsigned size      = get_type_size_bytes(get_entity_type(entity));
1260         unsigned alignment = get_effective_entity_alignment(entity);
1261
1262         if (get_entity_linkage(entity) & IR_LINKAGE_WEAK) {
1263                 emit_weak(entity);
1264         }
1265
1266         switch (be_gas_object_file_format) {
1267         case OBJECT_FILE_FORMAT_MACH_O:
1268                 be_emit_cstring("\t.lcomm ");
1269                 be_gas_emit_entity(entity);
1270                 be_emit_irprintf(",%u,%u\n", size, log2_floor(alignment));
1271                 be_emit_write_line();
1272                 return;
1273         case OBJECT_FILE_FORMAT_ELF:
1274                 be_emit_cstring("\t.local ");
1275                 be_gas_emit_entity(entity);
1276                 be_emit_cstring("\n");
1277                 be_emit_write_line();
1278                 be_emit_cstring("\t.comm ");
1279                 be_gas_emit_entity(entity);
1280                 be_emit_irprintf(",%u,%u\n", size, alignment);
1281                 be_emit_write_line();
1282                 return;
1283         case OBJECT_FILE_FORMAT_COFF:
1284                 be_emit_cstring("\t.lcomm ");
1285                 be_gas_emit_entity(entity);
1286                 be_emit_irprintf(",%u # %u\n", size, alignment);
1287                 be_emit_write_line();
1288                 return;
1289         }
1290         panic("invalid object file format");
1291 }
1292
1293 static void emit_indirect_symbol(const ir_entity *entity, be_gas_section_t section)
1294 {
1295         /* we can only do PIC code on macho so far */
1296         assert(be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O);
1297
1298         be_gas_emit_entity(entity);
1299         be_emit_cstring(":\n");
1300         be_emit_write_line();
1301         be_emit_irprintf("\t.indirect_symbol %I\n", get_entity_ident(entity));
1302         be_emit_write_line();
1303         if (section == GAS_SECTION_PIC_TRAMPOLINES) {
1304                 be_emit_cstring("\thlt ; hlt ; hlt ; hlt ; hlt\n");
1305                 be_emit_write_line();
1306         } else {
1307                 assert(section == GAS_SECTION_PIC_SYMBOLS);
1308                 be_emit_cstring("\t.long 0\n");
1309                 be_emit_write_line();
1310         }
1311 }
1312
1313 char const *be_gas_get_private_prefix(void)
1314 {
1315         return be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O ? "L" : ".L";
1316 }
1317
1318 void be_gas_emit_entity(const ir_entity *entity)
1319 {
1320         if (entity->type == get_code_type()) {
1321                 ir_label_t label = get_entity_label(entity);
1322                 be_emit_irprintf("%s_%lu", be_gas_get_private_prefix(), label);
1323                 return;
1324         }
1325
1326         if (get_entity_visibility(entity) == ir_visibility_private) {
1327                 be_emit_string(be_gas_get_private_prefix());
1328         }
1329         be_emit_irprintf("%I", get_entity_ld_ident(entity));
1330 }
1331
1332 void be_gas_emit_block_name(const ir_node *block)
1333 {
1334         ir_entity *entity = get_Block_entity(block);
1335         if (entity != NULL) {
1336                 be_gas_emit_entity(entity);
1337         } else {
1338                 void *nr_val = pmap_get(void, block_numbers, block);
1339                 int   nr;
1340                 if (nr_val == NULL) {
1341                         nr = next_block_nr++;
1342                         pmap_insert(block_numbers, block, INT_TO_PTR(nr+1));
1343                 } else {
1344                         nr = PTR_TO_INT(nr_val)-1;
1345                 }
1346                 be_emit_irprintf("%s%d", be_gas_get_private_prefix(), nr);
1347         }
1348 }
1349
1350 void be_gas_begin_block(const ir_node *block, bool needs_label)
1351 {
1352         if (needs_label) {
1353                 be_gas_emit_block_name(block);
1354                 be_emit_char(':');
1355         } else {
1356                 if (!be_options.verbose_asm)
1357                         return;
1358                 be_emit_cstring("/*");
1359                 be_gas_emit_block_name(block);
1360                 be_emit_cstring(":*/");
1361         }
1362
1363         if (be_options.verbose_asm) {
1364                 be_emit_pad_comment();
1365                 be_emit_irprintf("/* %+F preds:", block);
1366
1367                 int arity = get_irn_arity(block);
1368                 if (arity == 0) {
1369                         be_emit_cstring(" none");
1370                 } else {
1371                         int i;
1372                         for (i = 0; i < arity; ++i) {
1373                                 ir_node *predblock = get_Block_cfgpred_block(block, i);
1374                                 be_emit_char(' ');
1375                                 be_gas_emit_block_name(predblock);
1376                         }
1377                 }
1378                 be_emit_irprintf(", freq: %.3f */", get_block_execfreq(block));
1379         }
1380         be_emit_char('\n');
1381         be_emit_write_line();
1382 }
1383
1384 /**
1385  * Dump a global entity.
1386  *
1387  * @param env  the gas output environment
1388  * @param ent  the entity to be dumped
1389  */
1390 static void emit_global(be_gas_decl_env_t *env, const ir_entity *entity)
1391 {
1392         ir_type          *type       = get_entity_type(entity);
1393         ident            *ld_ident   = get_entity_ld_ident(entity);
1394         unsigned          alignment  = get_effective_entity_alignment(entity);
1395         be_gas_section_t  section    = determine_section(env, entity);
1396         ir_visibility     visibility = get_entity_visibility(entity);
1397         ir_linkage        linkage    = get_entity_linkage(entity);
1398
1399         /* Block labels are already emitted in the code. */
1400         if (type == get_code_type())
1401                 return;
1402
1403         /* we already emitted all methods with graphs in other functions like
1404          * be_gas_emit_function_prolog(). All others don't need to be emitted.
1405          */
1406         if (is_Method_type(type) && section != GAS_SECTION_PIC_TRAMPOLINES) {
1407                 return;
1408         }
1409
1410         be_dwarf_variable(entity);
1411
1412         if (section == GAS_SECTION_BSS) {
1413                 switch (visibility) {
1414                 case ir_visibility_local:
1415                 case ir_visibility_private:
1416                         emit_local_common(entity);
1417                         return;
1418                 case ir_visibility_external:
1419                         if (linkage & IR_LINKAGE_MERGE) {
1420                                 emit_common(entity);
1421                                 return;
1422                         }
1423                         break;
1424                 }
1425         }
1426
1427         emit_visibility(entity);
1428
1429         if (!is_po2(alignment))
1430                 panic("alignment not a power of 2");
1431
1432         emit_section(section, entity);
1433
1434         if (section == GAS_SECTION_PIC_TRAMPOLINES
1435                         || section == GAS_SECTION_PIC_SYMBOLS) {
1436                 emit_indirect_symbol(entity, section);
1437                 return;
1438         }
1439
1440         /* nothing left to do without an initializer */
1441         if (!entity_has_definition(entity))
1442                 return;
1443
1444         /* alignment */
1445         if (alignment > 1) {
1446                 emit_align(alignment);
1447         }
1448         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_ELF
1449                         && be_gas_emit_types
1450                         && visibility != ir_visibility_private) {
1451                 be_emit_cstring("\t.type\t");
1452                 be_gas_emit_entity(entity);
1453                 be_emit_cstring(", ");
1454                 be_emit_char(be_gas_elf_type_char);
1455                 be_emit_cstring("object\n\t.size\t");\
1456                 be_gas_emit_entity(entity);
1457                 be_emit_irprintf(", %u\n", get_type_size_bytes(type));
1458         }
1459
1460         if (get_id_str(ld_ident)[0] != '\0') {
1461                 be_gas_emit_entity(entity);
1462                 be_emit_cstring(":\n");
1463                 be_emit_write_line();
1464         }
1465
1466         if (entity_is_null(entity)) {
1467                 /* we should use .space for stuff in the bss segment */
1468                 unsigned size = get_type_size_bytes(type);
1469                 if (size > 0) {
1470                         be_emit_irprintf("\t.space %u, 0\n", get_type_size_bytes(type));
1471                         be_emit_write_line();
1472                 }
1473         } else {
1474                 assert(entity->initializer != NULL);
1475                 emit_initializer(env, entity);
1476         }
1477 }
1478
1479 /**
1480  * Dumps declarations of global variables and the initialization code.
1481  *
1482  * @param gt                a global like type, either the global or the TLS one
1483  * @param env               an environment
1484  */
1485 static void be_gas_emit_globals(ir_type *gt, be_gas_decl_env_t *env)
1486 {
1487         size_t i, n = get_compound_n_members(gt);
1488
1489         for (i = 0; i < n; i++) {
1490                 ir_entity *ent = get_compound_member(gt, i);
1491                 emit_global(env, ent);
1492         }
1493 }
1494
1495 /* Generate all entities. */
1496 static void emit_global_decls(const be_main_env_t *main_env)
1497 {
1498         be_gas_decl_env_t env;
1499         memset(&env, 0, sizeof(env));
1500
1501         /* dump global type */
1502         env.main_env = main_env;
1503         env.section  = (be_gas_section_t) -1;
1504
1505         be_gas_emit_globals(get_glob_type(), &env);
1506         be_gas_emit_globals(get_tls_type(), &env);
1507         be_gas_emit_globals(get_segment_type(IR_SEGMENT_CONSTRUCTORS), &env);
1508         be_gas_emit_globals(get_segment_type(IR_SEGMENT_DESTRUCTORS), &env);
1509         be_gas_emit_globals(main_env->pic_symbols_type, &env);
1510         be_gas_emit_globals(main_env->pic_trampolines_type, &env);
1511
1512         /**
1513          * ".subsections_via_symbols marks object files which are OK to divide
1514          * their section contents into individual blocks".
1515          * From my understanding this means no label points in the middle of an
1516          * object which we want to address as a whole. Firm code should be fine
1517          * with this.
1518          */
1519         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
1520                 be_emit_cstring("\t.subsections_via_symbols\n");
1521                 be_emit_write_line();
1522         }
1523 }
1524
1525 void be_emit_jump_table(const ir_node *node, const ir_switch_table *table,
1526                         ir_entity *entity, get_cfop_target_func get_cfop_target)
1527 {
1528         unsigned        n_outs    = arch_get_irn_n_outs(node);
1529         const ir_node **targets   = XMALLOCNZ(const ir_node*, n_outs);
1530         size_t          n_entries = ir_switch_table_get_n_entries(table);
1531         unsigned long   length    = 0;
1532         size_t          e;
1533         unsigned        i;
1534         const ir_node **labels;
1535
1536         /* go over all proj's and collect their jump targets */
1537         foreach_out_edge(node, edge) {
1538                 ir_node *proj   = get_edge_src_irn(edge);
1539                 long     pn     = get_Proj_proj(proj);
1540                 ir_node *target = get_cfop_target(proj);
1541                 assert(targets[pn] == NULL);
1542                 targets[pn] = target;
1543         }
1544
1545         /* go over table to determine max value (note that we normalized the
1546          * ranges so that the minimum is 0) */
1547         for (e = 0; e < n_entries; ++e) {
1548                 const ir_switch_table_entry *entry
1549                         = ir_switch_table_get_entry_const(table, e);
1550                 ir_tarval *max = entry->max;
1551                 unsigned long val;
1552                 if (entry->pn == 0)
1553                         continue;
1554                 if (!tarval_is_long(max))
1555                         panic("switch case overflow (%+F)", node);
1556                 val = (unsigned long) get_tarval_long(max);
1557                 if (val > length) {
1558                         length = val;
1559                 }
1560         }
1561
1562         /* the 16000 isn't a real limit of the architecture. But should protect us
1563          * from seamingly endless compiler runs */
1564         if (length > 16000) {
1565                 /* switch lowerer should have broken this monster to pieces... */
1566                 panic("too large switch encountered (%+F)", node);
1567         }
1568         ++length;
1569
1570         labels = XMALLOCNZ(const ir_node*, length);
1571         for (e = 0; e < n_entries; ++e) {
1572                 const ir_switch_table_entry *entry
1573                         = ir_switch_table_get_entry_const(table, e);
1574                 ir_tarval     *min    = entry->min;
1575                 ir_tarval     *max    = entry->max;
1576                 const ir_node *target = targets[entry->pn];
1577                 assert(entry->pn < (long)n_outs);
1578                 if (min == max) {
1579                         unsigned long val = (unsigned long)get_tarval_long(max);
1580                         labels[val] = target;
1581                 } else {
1582                         unsigned long min_val;
1583                         unsigned long max_val;
1584                         unsigned long i;
1585                         if (!tarval_is_long(min))
1586                                 panic("switch case overflow (%+F)", node);
1587                         min_val = (unsigned long)get_tarval_long(min);
1588                         max_val = (unsigned long)get_tarval_long(max);
1589                         assert(min_val <= max_val);
1590                         for (i = min_val; i <= max_val; ++i) {
1591                                 labels[i] = target;
1592                         }
1593                 }
1594         }
1595
1596         /* emit table */
1597         if (entity != NULL) {
1598                 be_gas_emit_switch_section(GAS_SECTION_RODATA);
1599                 be_emit_cstring("\t.align 4\n");
1600                 be_gas_emit_entity(entity);
1601                 be_emit_cstring(":\n");
1602         }
1603
1604         for (i = 0; i < length; ++i) {
1605                 const ir_node *block = labels[i];
1606                 if (block == NULL)
1607                         block = targets[0];
1608                 be_emit_cstring("\t.long ");
1609                 be_gas_emit_block_name(block);
1610                 be_emit_char('\n');
1611                 be_emit_write_line();
1612         }
1613
1614         if (entity != NULL)
1615                 be_gas_emit_switch_section(GAS_SECTION_TEXT);
1616
1617         xfree(labels);
1618         xfree(targets);
1619 }
1620
1621 static void emit_global_asms(void)
1622 {
1623         size_t n = get_irp_n_asms();
1624         size_t i;
1625
1626         be_gas_emit_switch_section(GAS_SECTION_TEXT);
1627         for (i = 0; i < n; ++i) {
1628                 ident *asmtext = get_irp_asm(i);
1629
1630                 be_emit_cstring("#APP\n");
1631                 be_emit_write_line();
1632                 be_emit_irprintf("%I\n", asmtext);
1633                 be_emit_write_line();
1634                 be_emit_cstring("#NO_APP\n");
1635                 be_emit_write_line();
1636         }
1637 }
1638
1639 void be_gas_begin_compilation_unit(const be_main_env_t *env)
1640 {
1641         be_dwarf_open();
1642         be_dwarf_unit_begin(env->cup_name);
1643
1644         block_numbers = pmap_create();
1645         next_block_nr = 0;
1646
1647         emit_global_asms();
1648 }
1649
1650 void be_gas_end_compilation_unit(const be_main_env_t *env)
1651 {
1652         emit_global_decls(env);
1653
1654         pmap_destroy(block_numbers);
1655
1656         be_dwarf_unit_end();
1657         be_dwarf_close();
1658 }