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
 596 /**
 597  * Output a tarval.
 598  *
 599  * @param tv     the tarval
 600  * @param bytes  the width of the tarvals value in bytes
 601  */
 602 static void emit_arith_tarval(ir_tarval *tv, unsigned bytes)
 603 {
 604         switch (bytes) {
 605         case 1:
 606                 be_emit_irprintf("0x%02x", get_tarval_sub_bits(tv, 0));
 607                 return;
 608
 609         case 2:
 610                 be_emit_irprintf("0x%02x%02x",
 611                         get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 612                 return;
 613
 614         case 4:
 615                 be_emit_irprintf("0x%02x%02x%02x%02x",
 616                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2),
 617                         get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 618                 return;
 619
 620         case 8:
 621                 be_emit_irprintf("0x%02x%02x%02x%02x%02x%02x%02x%02x",
 622                         get_tarval_sub_bits(tv, 7), get_tarval_sub_bits(tv, 6),
 623                         get_tarval_sub_bits(tv, 5), get_tarval_sub_bits(tv, 4),
 624                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2),
 625                         get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 626                 return;
 627         }
 628
 629         panic("Can't dump a tarval with %d bytes", bytes);
 630 }
 631
 632 /**
 633  * Return the label prefix for labeled instructions.
 634  */
 635 const char *be_gas_insn_label_prefix(void)
 636 {
 637         return ".LE";
 638 }
 639
 640 /**
 641  * Dump an atomic value.
 642  *
 643  * @param env   the gas output environment
 644  * @param init  a node representing the atomic value (on the const code irg)
 645  */
 646 static void emit_init_expression(be_gas_decl_env_t *env, ir_node *init)
 647 {
 648         ir_mode *mode = get_irn_mode(init);
 649         int bytes     = get_mode_size_bytes(mode);
 650         ir_tarval *tv;
 651         ir_entity *ent;
 652
 653         init = skip_Id(init);
 654
 655         switch (get_irn_opcode(init)) {
 656         case iro_Cast:
 657                 emit_init_expression(env, get_Cast_op(init));
 658                 return;
 659
 660         case iro_Conv:
 661                 emit_init_expression(env, get_Conv_op(init));
 662                 return;
 663
 664         case iro_Const:
 665                 tv = get_Const_tarval(init);
 666
 667                 /* it's an arithmetic value */
 668                 emit_arith_tarval(tv, bytes);
 669                 return;
 670
 671         case iro_SymConst:
 672                 switch (get_SymConst_kind(init)) {
 673                 case symconst_addr_ent:
 674                         ent = get_SymConst_entity(init);
 675                         be_gas_emit_entity(ent);
 676                         break;
 677
 678                 case symconst_ofs_ent:
 679                         ent = get_SymConst_entity(init);
 680                         be_emit_irprintf("%d", get_entity_offset(ent));
 681                         break;
 682
 683                 case symconst_type_size:
 684                         be_emit_irprintf("%u", get_type_size_bytes(get_SymConst_type(init)));
 685                         break;
 686
 687                 case symconst_type_align:
 688                         be_emit_irprintf("%u", get_type_alignment_bytes(get_SymConst_type(init)));
 689                         break;
 690
 691                 case symconst_enum_const:
 692                         tv = get_enumeration_value(get_SymConst_enum(init));
 693                         emit_arith_tarval(tv, bytes);
 694                         break;
 695
 696                 default:
 697                         assert(!"emit_atomic_init(): don't know how to init from this SymConst");
 698                 }
 699                 return;
 700
 701         case iro_Add:
 702                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 703                         panic("Constant must be int or pointer for '+' to work");
 704                 }
 705                 emit_init_expression(env, get_Add_left(init));
 706                 be_emit_cstring(" + ");
 707                 emit_init_expression(env, get_Add_right(init));
 708                 return;
 709
 710         case iro_Sub:
 711                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 712                         panic("Constant must be int or pointer for '-' to work");
 713                 }
 714                 emit_init_expression(env, get_Sub_left(init));
 715                 be_emit_cstring(" - ");
 716                 emit_init_expression(env, get_Sub_right(init));
 717                 return;
 718
 719         case iro_Mul:
 720                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 721                         panic("Constant must be int or pointer for '*' to work");
 722                 }
 723                 emit_init_expression(env, get_Mul_left(init));
 724                 be_emit_cstring(" * ");
 725                 emit_init_expression(env, get_Mul_right(init));
 726                 return;
 727
 728         case iro_Unknown:
 729                 be_emit_cstring("0");
 730                 return;
 731
 732         default:
 733                 panic("emit_atomic_init(): unsupported IR-node %+F", init);
 734         }
 735 }
 736
 737 /**
 738  * Dumps the type for given size (.byte, .long, ...)
 739  *
 740  * @param size  the size in bytes
 741  */
 742 static void emit_size_type(size_t size)
 743 {
 744         switch (size) {
 745         case 1: be_emit_cstring("\t.byte\t");  break;
 746         case 2: be_emit_cstring("\t.short\t"); break;
 747         case 4: be_emit_cstring("\t.long\t");  break;
 748         case 8: be_emit_cstring("\t.quad\t");  break;
 749
 750         default:
 751                 panic("Try to dump a type with %u bytes", (unsigned)size);
 752         }
 753 }
 754
 755 static size_t emit_string_initializer(const ir_initializer_t *initializer)
 756 {
 757         size_t i, len;
 758
 759         len = initializer->compound.n_initializers;
 760         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 761                 be_emit_cstring("\t.ascii \"");
 762         } else {
 763                 be_emit_cstring("\t.string \"");
 764                 len -= 1;
 765         }
 766
 767         for (i = 0; i < len; ++i) {
 768                 const ir_initializer_t *sub_initializer
 769                         = get_initializer_compound_value(initializer, i);
 770
 771                 ir_tarval *tv = get_initializer_tarval(sub_initializer);
 772                 int        c  = get_tarval_long(tv);
 773
 774                 switch (c) {
 775                 case '"' : be_emit_cstring("\\\""); break;
 776                 case '\n': be_emit_cstring("\\n"); break;
 777                 case '\r': be_emit_cstring("\\r"); break;
 778                 case '\t': be_emit_cstring("\\t"); break;
 779                 case '\\': be_emit_cstring("\\\\"); break;
 780                 default  :
 781                         if (isprint(c))
 782                                 be_emit_char(c);
 783                         else
 784                                 be_emit_irprintf("\\%03o", c);
 785                         break;
 786                 }
 787         }
 788         be_emit_cstring("\"\n");
 789         be_emit_write_line();
 790
 791         return initializer->compound.n_initializers;
 792 }
 793
 794 typedef enum normal_or_bitfield_kind {
 795         NORMAL = 0,
 796         TARVAL,
 797         STRING,
 798         BITFIELD
 799 } normal_or_bitfield_kind;
 800
 801 typedef struct {
 802         normal_or_bitfield_kind kind;
 803         ir_type                *type;
 804         union {
 805                 ir_node                *value;
 806                 ir_tarval              *tarval;
 807                 unsigned char           bf_val;
 808                 const ir_initializer_t *string;
 809         } v;
 810 } normal_or_bitfield;
 811
 812 static size_t get_initializer_size(const ir_initializer_t *initializer,
 813                                    ir_type *type)
 814 {
 815         switch (get_initializer_kind(initializer)) {
 816         case IR_INITIALIZER_TARVAL:
 817                 assert(get_tarval_mode(get_initializer_tarval_value(initializer)) == get_type_mode(type));
 818                 return get_type_size_bytes(type);
 819         case IR_INITIALIZER_CONST:
 820         case IR_INITIALIZER_NULL:
 821                 return get_type_size_bytes(type);
 822         case IR_INITIALIZER_COMPOUND:
 823                 if (is_Array_type(type)) {
 824                         if (is_array_variable_size(type)) {
 825                                 ir_type   *element_type = get_array_element_type(type);
 826                                 unsigned   element_size = get_type_size_bytes(element_type);
 827                                 unsigned   element_align
 828                                         = get_type_alignment_bytes(element_type);
 829                                 unsigned   misalign     = element_size % element_align;
 830                                 size_t     n_inits
 831                                         = get_initializer_compound_n_entries(initializer);
 832                                 element_size += element_align - misalign;
 833                                 return n_inits * element_size;
 834                         } else {
 835                                 return get_type_size_bytes(type);
 836                         }
 837                 } else {
 838                         assert(is_compound_type(type));
 839                         size_t size = get_type_size_bytes(type);
 840                         if (is_compound_variable_size(type)) {
 841                                 /* last initializer has to be an array of variable size */
 842                                 size_t l = get_initializer_compound_n_entries(initializer)-1;
 843                                 const ir_initializer_t *last
 844                                         = get_initializer_compound_value(initializer, l);
 845                                 const ir_entity *last_ent  = get_compound_member(type, l);
 846                                 ir_type         *last_type = get_entity_type(last_ent);
 847                                 assert(is_array_variable_size(last_type));
 848                                 size += get_initializer_size(last, last_type);
 849                         }
 850                         return size;
 851                 }
 852         }
 853
 854         panic("found invalid initializer");
 855 }
 856
 857 #ifndef NDEBUG
 858 static normal_or_bitfield *glob_vals;
 859 static size_t              max_vals;
 860 #endif
 861
 862 static void emit_bitfield(normal_or_bitfield *vals, size_t offset_bits,
 863                           const ir_initializer_t *initializer, ir_type *type)
 864 {
 865         static const size_t BITS_PER_BYTE = 8;
 866         ir_mode   *mode      = get_type_mode(type);
 867         ir_tarval *tv        = NULL;
 868         int        value_len;
 869         size_t     bit_offset;
 870         size_t     end;
 871         bool       big_endian = be_get_backend_param()->byte_order_big_endian;
 872
 873         switch (get_initializer_kind(initializer)) {
 874         case IR_INITIALIZER_NULL:
 875                 return;
 876         case IR_INITIALIZER_TARVAL:
 877                 tv = get_initializer_tarval_value(initializer);
 878                 break;
 879         case IR_INITIALIZER_CONST: {
 880                 ir_node *node = get_initializer_const_value(initializer);
 881                 if (!is_Const(node)) {
 882                         panic("bitfield initializer not a Const node");
 883                 }
 884                 tv = get_Const_tarval(node);
 885                 break;
 886         }
 887         case IR_INITIALIZER_COMPOUND:
 888                 panic("bitfield initializer is compound");
 889         }
 890         if (tv == NULL) {
 891                 panic("Couldn't get numeric value for bitfield initializer");
 892         }
 893         tv = tarval_convert_to(tv, get_type_mode(type));
 894
 895         value_len  = get_type_size_bytes(get_primitive_base_type(type));
 896         bit_offset = 0;
 897         end        = get_mode_size_bits(mode);
 898         while (bit_offset < end) {
 899                 size_t        src_offset      = bit_offset / BITS_PER_BYTE;
 900                 size_t        src_offset_bits = bit_offset % BITS_PER_BYTE;
 901                 size_t        dst_offset      = (bit_offset+offset_bits) / BITS_PER_BYTE;
 902                 size_t        dst_offset_bits = (bit_offset+offset_bits) % BITS_PER_BYTE;
 903                 size_t        src_bits_len    = end-bit_offset;
 904                 size_t        dst_bits_len    = BITS_PER_BYTE-dst_offset_bits;
 905                 unsigned char curr_bits;
 906                 normal_or_bitfield *val;
 907                 if (src_bits_len > dst_bits_len)
 908                         src_bits_len = dst_bits_len;
 909
 910                 if (big_endian) {
 911                         val = &vals[value_len - dst_offset - 1];
 912                 } else {
 913                         val = &vals[dst_offset];
 914                 }
 915
 916                 assert((val-glob_vals) < (ptrdiff_t) max_vals);
 917                 assert(val->kind == BITFIELD ||
 918                                 (val->kind == NORMAL && val->v.value == NULL));
 919                 val->kind  = BITFIELD;
 920                 curr_bits  = get_tarval_sub_bits(tv, src_offset);
 921                 curr_bits  = curr_bits >> src_offset_bits;
 922                 if (src_offset_bits + src_bits_len > 8) {
 923                         unsigned next_bits = get_tarval_sub_bits(tv, src_offset+1);
 924                         curr_bits |= next_bits << (8 - src_offset_bits);
 925                 }
 926                 curr_bits &= (1 << src_bits_len) - 1;
 927                 val->v.bf_val |= curr_bits << dst_offset_bits;
 928
 929                 bit_offset += dst_bits_len;
 930         }
 931 }
 932
 933 static void emit_ir_initializer(normal_or_bitfield *vals,
 934                                 const ir_initializer_t *initializer,
 935                                 ir_type *type)
 936 {
 937         assert((size_t) (vals - glob_vals) < max_vals);
 938
 939         if (initializer_is_string_const(initializer)) {
 940                 assert(vals->kind != BITFIELD);
 941                 vals->kind     = STRING;
 942                 vals->v.string = initializer;
 943                 return;
 944         }
 945
 946         switch (get_initializer_kind(initializer)) {
 947         case IR_INITIALIZER_NULL:
 948                 return;
 949         case IR_INITIALIZER_TARVAL: {
 950                 size_t i;
 951
 952                 assert(vals->kind != BITFIELD);
 953                 vals->kind     = TARVAL;
 954                 vals->type     = type;
 955                 vals->v.tarval = get_initializer_tarval_value(initializer);
 956                 assert(get_type_mode(type) == get_tarval_mode(vals->v.tarval));
 957                 for (i = 1; i < get_type_size_bytes(type); ++i) {
 958                         vals[i].kind    = NORMAL;
 959                         vals[i].type    = NULL;
 960                         vals[i].v.value = NULL;
 961                 }
 962                 return;
 963         }
 964         case IR_INITIALIZER_CONST: {
 965                 size_t i;
 966
 967                 assert(vals->kind != BITFIELD);
 968                 vals->kind    = NORMAL;
 969                 vals->type    = type;
 970                 vals->v.value = get_initializer_const_value(initializer);
 971                 for (i = 1; i < get_type_size_bytes(type); ++i) {
 972                         vals[i].kind    = NORMAL;
 973                         vals[i].type    = NULL;
 974                         vals[i].v.value = NULL;
 975                 }
 976                 return;
 977         }
 978         case IR_INITIALIZER_COMPOUND: {
 979                 size_t i = 0;
 980                 size_t n = get_initializer_compound_n_entries(initializer);
 981
 982                 if (is_Array_type(type)) {
 983                         ir_type *element_type = get_array_element_type(type);
 984                         size_t   skip         = get_type_size_bytes(element_type);
 985                         size_t   alignment    = get_type_alignment_bytes(element_type);
 986                         size_t   misalign     = skip % alignment;
 987                         if (misalign != 0) {
 988                                 skip += alignment - misalign;
 989                         }
 990
 991                         for (i = 0; i < n; ++i) {
 992                                 ir_initializer_t *sub_initializer
 993                                         = get_initializer_compound_value(initializer, i);
 994
 995                                 emit_ir_initializer(vals, sub_initializer, element_type);
 996
 997                                 vals += skip;
 998                         }
 999                 } else {
1000                         size_t n_members, i;
1001                         assert(is_compound_type(type));
1002                         n_members = get_compound_n_members(type);
1003                         for (i = 0; i < n_members; ++i) {
1004                                 ir_entity        *member    = get_compound_member(type, i);
1005                                 size_t            offset    = get_entity_offset(member);
1006                                 ir_type          *subtype   = get_entity_type(member);
1007                                 ir_mode          *mode      = get_type_mode(subtype);
1008                                 ir_initializer_t *sub_initializer;
1009
1010                                 assert(i < get_initializer_compound_n_entries(initializer));
1011                                 sub_initializer
1012                                         = get_initializer_compound_value(initializer, i);
1013
1014                                 if (mode != NULL) {
1015                                         size_t offset_bits
1016                                                 = get_entity_offset_bits_remainder(member);
1017
1018                                         if (is_Primitive_type(subtype)
1019                                                         && get_primitive_base_type(subtype) != NULL) {
1020                                                 emit_bitfield(&vals[offset], offset_bits,
1021                                                               sub_initializer, subtype);
1022                                                 continue;
1023                                         } else {
1024                                                 assert(offset_bits == 0);
1025                                         }
1026                                 }
1027
1028                                 emit_ir_initializer(&vals[offset], sub_initializer, subtype);
1029                         }
1030                 }
1031
1032                 return;
1033         }
1034         }
1035         panic("invalid ir_initializer kind found");
1036 }
1037
1038 static void emit_tarval_data(ir_type *type, ir_tarval *tv)
1039 {
1040         size_t size = get_type_size_bytes(type);
1041         if (size == 12) {
1042                 /* this should be an x86 extended float */
1043                 assert(be_get_backend_param()->byte_order_big_endian == 0);
1044
1045                 /* Beware: Mixed endian output!  One little endian number emitted as
1046                  * three longs.  Each long initializer is written in big endian. */
1047                 be_emit_irprintf(
1048                         "\t.long\t0x%02x%02x%02x%02x\n"
1049                         "\t.long\t0x%02x%02x%02x%02x\n"
1050                         "\t.long\t0x%02x%02x%02x%02x\n",
1051                         get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
1052                         get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0),
1053                         get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
1054                         get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
1055                         get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
1056                         get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8)
1057                 );
1058                 be_emit_write_line();
1059         } else if (size == 16) {
1060                 if (be_get_backend_param()->byte_order_big_endian) {
1061                         be_emit_irprintf(
1062                                 "\t.long\t0x%02x%02x%02x%02x\n"
1063                                 "\t.long\t0x%02x%02x%02x%02x\n"
1064                                 "\t.long\t0x%02x%02x%02x%02x\n"
1065                                 "\t.long\t0x%02x%02x%02x%02x\n",
1066                                 get_tarval_sub_bits(tv, 15), get_tarval_sub_bits(tv, 14),
1067                                 get_tarval_sub_bits(tv, 13), get_tarval_sub_bits(tv, 12),
1068                                 get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
1069                                 get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8),
1070                                 get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
1071                                 get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
1072                                 get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
1073                                 get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0)
1074                         );
1075                 } else {
1076                         /* Beware: Mixed endian output! One little endian number emitted as
1077                          * three longs.  Each long initializer is written in big endian. */
1078                         be_emit_irprintf(
1079                                 "\t.long\t0x%02x%02x%02x%02x\n"
1080                                 "\t.long\t0x%02x%02x%02x%02x\n"
1081                                 "\t.long\t0x%02x%02x%02x%02x\n"
1082                                 "\t.long\t0x%02x%02x%02x%02x\n",
1083                                 get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
1084                                 get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0),
1085                                 get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
1086                                 get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
1087                                 get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
1088                                 get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8),
1089                                 get_tarval_sub_bits(tv, 15), get_tarval_sub_bits(tv, 14),
1090                                 get_tarval_sub_bits(tv, 13), get_tarval_sub_bits(tv, 12)
1091                         );
1092                 }
1093                 be_emit_write_line();
1094                 return;
1095         } else {
1096                 /* default case */
1097                 emit_size_type(size);
1098                 emit_arith_tarval(tv, size);
1099                 be_emit_char('\n');
1100                 be_emit_write_line();
1101         }
1102 }
1103
1104 /**
1105  * Emit an atomic value.
1106  *
1107  * @param env   the gas output environment
1108  * @param init  a node representing the atomic value (on the const code irg)
1109  */
1110 static void emit_node_data(be_gas_decl_env_t *env, ir_node *init, ir_type *type)
1111 {
1112         size_t size = get_type_size_bytes(type);
1113         if (size == 12 || size == 16) {
1114                 ir_tarval *tv;
1115                 if (!is_Const(init)) {
1116                         panic("12/16byte initializers only support Const nodes yet");
1117                 }
1118                 tv = get_Const_tarval(init);
1119                 emit_tarval_data(type, tv);
1120                 return;
1121         }
1122
1123         emit_size_type(size);
1124         emit_init_expression(env, init);
1125         be_emit_char('\n');
1126         be_emit_write_line();
1127 }
1128
1129 static void emit_initializer(be_gas_decl_env_t *env, const ir_entity *entity)
1130 {
1131         const ir_initializer_t *initializer = entity->initializer;
1132         ir_type                *type;
1133         normal_or_bitfield     *vals;
1134         size_t                  size;
1135         size_t                  k;
1136
1137         if (initializer_is_string_const(initializer)) {
1138                 emit_string_initializer(initializer);
1139                 return;
1140         }
1141
1142         type = get_entity_type(entity);
1143         size = get_initializer_size(initializer, type);
1144
1145         if (size == 0)
1146                 return;
1147
1148         /*
1149          * In the worst case, every initializer allocates one byte.
1150          * Moreover, initializer might be big, do not allocate on stack.
1151          */
1152         vals = XMALLOCNZ(normal_or_bitfield, size);
1153
1154 #ifndef NDEBUG
1155         glob_vals = vals;
1156         max_vals  = size;
1157 #endif
1158
1159         emit_ir_initializer(vals, initializer, type);
1160
1161         /* now write values sorted */
1162         for (k = 0; k < size; ) {
1163                 int                     space     = 0;
1164                 normal_or_bitfield_kind kind      = vals[k].kind;
1165                 int                     elem_size;
1166                 switch (kind) {
1167                 case NORMAL:
1168                         if (vals[k].v.value != NULL) {
1169                                 emit_node_data(env, vals[k].v.value, vals[k].type);
1170                                 elem_size = get_type_size_bytes(vals[k].type);
1171                         } else {
1172                                 elem_size = 0;
1173                         }
1174                         break;
1175                 case TARVAL:
1176                         emit_tarval_data(vals[k].type, vals[k].v.tarval);
1177                         elem_size = get_type_size_bytes(vals[k].type);
1178                         break;
1179                 case STRING:
1180                         elem_size = emit_string_initializer(vals[k].v.string);
1181                         break;
1182                 case BITFIELD:
1183                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
1184                         be_emit_write_line();
1185                         elem_size = 1;
1186                         break;
1187                 default:
1188                         panic("internal compiler error (invalid normal_or_bitfield_kind");
1189                 }
1190
1191                 k += elem_size;
1192                 while (k < size && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
1193                         ++space;
1194                         ++k;
1195                 }
1196
1197                 /* a gap */
1198                 if (space > 0) {
1199                         be_emit_irprintf("\t.space\t%d, 0\n", space);
1200                         be_emit_write_line();
1201                 }
1202         }
1203         xfree(vals);
1204 }
1205
1206 static void emit_align(unsigned p2alignment)
1207 {
1208         be_emit_irprintf("\t.p2align\t%u\n", log2_floor(p2alignment));
1209         be_emit_write_line();
1210 }
1211
1212 static unsigned get_effective_entity_alignment(const ir_entity *entity)
1213 {
1214         unsigned alignment = get_entity_alignment(entity);
1215         if (alignment == 0) {
1216                 ir_type *type = get_entity_type(entity);
1217                 alignment     = get_type_alignment_bytes(type);
1218         }
1219         return alignment;
1220 }
1221
1222 static void emit_common(const ir_entity *entity)
1223 {
1224         unsigned size      = get_type_size_bytes(get_entity_type(entity));
1225         unsigned alignment = get_effective_entity_alignment(entity);
1226
1227         if (get_entity_linkage(entity) & IR_LINKAGE_WEAK) {
1228                 emit_weak(entity);
1229         }
1230
1231         switch (be_gas_object_file_format) {
1232         case OBJECT_FILE_FORMAT_MACH_O:
1233                 be_emit_cstring("\t.comm ");
1234                 be_gas_emit_entity(entity);
1235                 be_emit_irprintf(",%u,%u\n", size, log2_floor(alignment));
1236                 be_emit_write_line();
1237                 return;
1238         case OBJECT_FILE_FORMAT_ELF:
1239                 be_emit_cstring("\t.comm ");
1240                 be_gas_emit_entity(entity);
1241                 be_emit_irprintf(",%u,%u\n", size, alignment);
1242                 be_emit_write_line();
1243                 return;
1244         case OBJECT_FILE_FORMAT_COFF:
1245                 be_emit_cstring("\t.comm ");
1246                 be_gas_emit_entity(entity);
1247                 be_emit_irprintf(",%u # %u\n", size, alignment);
1248                 be_emit_write_line();
1249                 return;
1250         }
1251         panic("invalid object file format");
1252 }
1253
1254 static void emit_local_common(const ir_entity *entity)
1255 {
1256         unsigned size      = get_type_size_bytes(get_entity_type(entity));
1257         unsigned alignment = get_effective_entity_alignment(entity);
1258
1259         if (get_entity_linkage(entity) & IR_LINKAGE_WEAK) {
1260                 emit_weak(entity);
1261         }
1262
1263         switch (be_gas_object_file_format) {
1264         case OBJECT_FILE_FORMAT_MACH_O:
1265                 be_emit_cstring("\t.lcomm ");
1266                 be_gas_emit_entity(entity);
1267                 be_emit_irprintf(",%u,%u\n", size, log2_floor(alignment));
1268                 be_emit_write_line();
1269                 return;
1270         case OBJECT_FILE_FORMAT_ELF:
1271                 be_emit_cstring("\t.local ");
1272                 be_gas_emit_entity(entity);
1273                 be_emit_cstring("\n");
1274                 be_emit_write_line();
1275                 be_emit_cstring("\t.comm ");
1276                 be_gas_emit_entity(entity);
1277                 be_emit_irprintf(",%u,%u\n", size, alignment);
1278                 be_emit_write_line();
1279                 return;
1280         case OBJECT_FILE_FORMAT_COFF:
1281                 be_emit_cstring("\t.lcomm ");
1282                 be_gas_emit_entity(entity);
1283                 be_emit_irprintf(",%u # %u\n", size, alignment);
1284                 be_emit_write_line();
1285                 return;
1286         }
1287         panic("invalid object file format");
1288 }
1289
1290 static void emit_indirect_symbol(const ir_entity *entity, be_gas_section_t section)
1291 {
1292         /* we can only do PIC code on macho so far */
1293         assert(be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O);
1294
1295         be_gas_emit_entity(entity);
1296         be_emit_cstring(":\n");
1297         be_emit_write_line();
1298         be_emit_irprintf("\t.indirect_symbol %I\n", get_entity_ident(entity));
1299         be_emit_write_line();
1300         if (section == GAS_SECTION_PIC_TRAMPOLINES) {
1301                 be_emit_cstring("\thlt ; hlt ; hlt ; hlt ; hlt\n");
1302                 be_emit_write_line();
1303         } else {
1304                 assert(section == GAS_SECTION_PIC_SYMBOLS);
1305                 be_emit_cstring("\t.long 0\n");
1306                 be_emit_write_line();
1307         }
1308 }
1309
1310 char const *be_gas_get_private_prefix(void)
1311 {
1312         return be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O ? "L" : ".L";
1313 }
1314
1315 void be_gas_emit_entity(const ir_entity *entity)
1316 {
1317         if (entity->type == get_code_type()) {
1318                 ir_label_t label = get_entity_label(entity);
1319                 be_emit_irprintf("%s_%lu", be_gas_get_private_prefix(), label);
1320                 return;
1321         }
1322
1323         if (get_entity_visibility(entity) == ir_visibility_private) {
1324                 be_emit_string(be_gas_get_private_prefix());
1325         }
1326         be_emit_irprintf("%I", get_entity_ld_ident(entity));
1327 }
1328
1329 void be_gas_emit_block_name(const ir_node *block)
1330 {
1331         ir_entity *entity = get_Block_entity(block);
1332         if (entity != NULL) {
1333                 be_gas_emit_entity(entity);
1334         } else {
1335                 void *nr_val = pmap_get(void, block_numbers, block);
1336                 int   nr;
1337                 if (nr_val == NULL) {
1338                         nr = next_block_nr++;
1339                         pmap_insert(block_numbers, block, INT_TO_PTR(nr+1));
1340                 } else {
1341                         nr = PTR_TO_INT(nr_val)-1;
1342                 }
1343                 be_emit_irprintf("%s%d", be_gas_get_private_prefix(), nr);
1344         }
1345 }
1346
1347 void be_gas_begin_block(const ir_node *block, bool needs_label)
1348 {
1349         if (needs_label) {
1350                 be_gas_emit_block_name(block);
1351                 be_emit_char(':');
1352         } else {
1353                 if (!be_options.verbose_asm)
1354                         return;
1355                 be_emit_cstring("/*");
1356                 be_gas_emit_block_name(block);
1357                 be_emit_cstring(":*/");
1358         }
1359
1360         if (be_options.verbose_asm) {
1361                 int           arity;
1362                 ir_graph     *irg       = get_irn_irg(block);
1363                 ir_exec_freq *exec_freq = be_get_irg_exec_freq(irg);
1364
1365                 be_emit_pad_comment();
1366                 be_emit_irprintf("/* %+F preds:", block);
1367
1368                 arity = get_irn_arity(block);
1369                 if (arity == 0) {
1370                         be_emit_cstring(" none");
1371                 } else {
1372                         int i;
1373                         for (i = 0; i < arity; ++i) {
1374                                 ir_node *predblock = get_Block_cfgpred_block(block, i);
1375                                 be_emit_char(' ');
1376                                 be_gas_emit_block_name(predblock);
1377                         }
1378                 }
1379                 if (exec_freq != NULL) {
1380                         be_emit_irprintf(", freq: %.3f",
1381                                          get_block_execfreq(exec_freq, block));
1382                 }
1383                 be_emit_cstring(" */");
1384         }
1385         be_emit_char('\n');
1386         be_emit_write_line();
1387 }
1388
1389 /**
1390  * Dump a global entity.
1391  *
1392  * @param env  the gas output environment
1393  * @param ent  the entity to be dumped
1394  */
1395 static void emit_global(be_gas_decl_env_t *env, const ir_entity *entity)
1396 {
1397         ir_type          *type       = get_entity_type(entity);
1398         ident            *ld_ident   = get_entity_ld_ident(entity);
1399         unsigned          alignment  = get_effective_entity_alignment(entity);
1400         be_gas_section_t  section    = determine_section(env, entity);
1401         ir_visibility     visibility = get_entity_visibility(entity);
1402         ir_linkage        linkage    = get_entity_linkage(entity);
1403
1404         /* Block labels are already emitted in the code. */
1405         if (type == get_code_type())
1406                 return;
1407
1408         /* we already emitted all methods with graphs in other functions like
1409          * be_gas_emit_function_prolog(). All others don't need to be emitted.
1410          */
1411         if (is_Method_type(type) && section != GAS_SECTION_PIC_TRAMPOLINES) {
1412                 return;
1413         }
1414
1415         be_dwarf_variable(entity);
1416
1417         if (section == GAS_SECTION_BSS) {
1418                 switch (visibility) {
1419                 case ir_visibility_local:
1420                 case ir_visibility_private:
1421                         emit_local_common(entity);
1422                         return;
1423                 case ir_visibility_external:
1424                         if (linkage & IR_LINKAGE_MERGE) {
1425                                 emit_common(entity);
1426                                 return;
1427                         }
1428                         break;
1429                 }
1430         }
1431
1432         emit_visibility(entity);
1433
1434         if (!is_po2(alignment))
1435                 panic("alignment not a power of 2");
1436
1437         emit_section(section, entity);
1438
1439         if (section == GAS_SECTION_PIC_TRAMPOLINES
1440                         || section == GAS_SECTION_PIC_SYMBOLS) {
1441                 emit_indirect_symbol(entity, section);
1442                 return;
1443         }
1444
1445         /* nothing left to do without an initializer */
1446         if (!entity_has_definition(entity))
1447                 return;
1448
1449         /* alignment */
1450         if (alignment > 1) {
1451                 emit_align(alignment);
1452         }
1453         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_ELF
1454                         && be_gas_emit_types
1455                         && visibility != ir_visibility_private) {
1456                 be_emit_cstring("\t.type\t");
1457                 be_gas_emit_entity(entity);
1458                 be_emit_cstring(", ");
1459                 be_emit_char(be_gas_elf_type_char);
1460                 be_emit_cstring("object\n\t.size\t");\
1461                 be_gas_emit_entity(entity);
1462                 be_emit_irprintf(", %u\n", get_type_size_bytes(type));
1463         }
1464
1465         if (get_id_str(ld_ident)[0] != '\0') {
1466                 be_gas_emit_entity(entity);
1467                 be_emit_cstring(":\n");
1468                 be_emit_write_line();
1469         }
1470
1471         if (entity_is_null(entity)) {
1472                 /* we should use .space for stuff in the bss segment */
1473                 unsigned size = get_type_size_bytes(type);
1474                 if (size > 0) {
1475                         be_emit_irprintf("\t.space %u, 0\n", get_type_size_bytes(type));
1476                         be_emit_write_line();
1477                 }
1478         } else {
1479                 assert(entity->initializer != NULL);
1480                 emit_initializer(env, entity);
1481         }
1482 }
1483
1484 /**
1485  * Dumps declarations of global variables and the initialization code.
1486  *
1487  * @param gt                a global like type, either the global or the TLS one
1488  * @param env               an environment
1489  */
1490 static void be_gas_emit_globals(ir_type *gt, be_gas_decl_env_t *env)
1491 {
1492         size_t i, n = get_compound_n_members(gt);
1493
1494         for (i = 0; i < n; i++) {
1495                 ir_entity *ent = get_compound_member(gt, i);
1496                 emit_global(env, ent);
1497         }
1498 }
1499
1500 /* Generate all entities. */
1501 static void emit_global_decls(const be_main_env_t *main_env)
1502 {
1503         be_gas_decl_env_t env;
1504         memset(&env, 0, sizeof(env));
1505
1506         /* dump global type */
1507         env.main_env = main_env;
1508         env.section  = (be_gas_section_t) -1;
1509
1510         be_gas_emit_globals(get_glob_type(), &env);
1511         be_gas_emit_globals(get_tls_type(), &env);
1512         be_gas_emit_globals(get_segment_type(IR_SEGMENT_CONSTRUCTORS), &env);
1513         be_gas_emit_globals(get_segment_type(IR_SEGMENT_DESTRUCTORS), &env);
1514         be_gas_emit_globals(main_env->pic_symbols_type, &env);
1515         be_gas_emit_globals(main_env->pic_trampolines_type, &env);
1516
1517         /**
1518          * ".subsections_via_symbols marks object files which are OK to divide
1519          * their section contents into individual blocks".
1520          * From my understanding this means no label points in the middle of an
1521          * object which we want to address as a whole. Firm code should be fine
1522          * with this.
1523          */
1524         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
1525                 be_emit_cstring("\t.subsections_via_symbols\n");
1526                 be_emit_write_line();
1527         }
1528 }
1529
1530 void be_emit_jump_table(const ir_node *node, const ir_switch_table *table,
1531                         ir_entity *entity, get_cfop_target_func get_cfop_target)
1532 {
1533         unsigned          n_outs    = arch_get_irn_n_outs(node);
1534         const ir_node   **targets   = XMALLOCNZ(const ir_node*, n_outs);
1535         size_t            n_entries = ir_switch_table_get_n_entries(table);
1536         unsigned long     length    = 0;
1537         size_t            e;
1538         const ir_edge_t  *edge;
1539         unsigned          i;
1540         const ir_node   **labels;
1541
1542         /* go over all proj's and collect their jump targets */
1543         foreach_out_edge(node, edge) {
1544                 ir_node *proj   = get_edge_src_irn(edge);
1545                 long     pn     = get_Proj_proj(proj);
1546                 ir_node *target = get_cfop_target(proj);
1547                 assert(targets[pn] == NULL);
1548                 targets[pn] = target;
1549         }
1550
1551         /* go over table to determine max value (note that we normalized the
1552          * ranges so that the minimum is 0) */
1553         for (e = 0; e < n_entries; ++e) {
1554                 const ir_switch_table_entry *entry
1555                         = ir_switch_table_get_entry_const(table, e);
1556                 ir_tarval *max = entry->max;
1557                 unsigned long val;
1558                 if (entry->pn == 0)
1559                         continue;
1560                 if (!tarval_is_long(max))
1561                         panic("switch case overflow (%+F)", node);
1562                 val = (unsigned long) get_tarval_long(max);
1563                 if (val > length) {
1564                         length = val;
1565                 }
1566         }
1567
1568         /* the 16000 isn't a real limit of the architecture. But should protect us
1569          * from seamingly endless compiler runs */
1570         if (length > 16000) {
1571                 /* switch lowerer should have broken this monster to pieces... */
1572                 panic("too large switch encountered (%+F)", node);
1573         }
1574         ++length;
1575
1576         labels = XMALLOCNZ(const ir_node*, length);
1577         for (e = 0; e < n_entries; ++e) {
1578                 const ir_switch_table_entry *entry
1579                         = ir_switch_table_get_entry_const(table, e);
1580                 ir_tarval     *min    = entry->min;
1581                 ir_tarval     *max    = entry->max;
1582                 const ir_node *target = targets[entry->pn];
1583                 assert(entry->pn < (long)n_outs);
1584                 if (min == max) {
1585                         unsigned long val = (unsigned long)get_tarval_long(max);
1586                         labels[val] = target;
1587                 } else {
1588                         unsigned long min_val;
1589                         unsigned long max_val;
1590                         unsigned long i;
1591                         if (!tarval_is_long(min))
1592                                 panic("switch case overflow (%+F)", node);
1593                         min_val = (unsigned long)get_tarval_long(min);
1594                         max_val = (unsigned long)get_tarval_long(max);
1595                         assert(min_val <= max_val);
1596                         for (i = min_val; i <= max_val; ++i) {
1597                                 labels[i] = target;
1598                         }
1599                 }
1600         }
1601
1602         /* emit table */
1603         if (entity != NULL) {
1604                 be_gas_emit_switch_section(GAS_SECTION_RODATA);
1605                 be_emit_cstring("\t.align 4\n");
1606                 be_gas_emit_entity(entity);
1607                 be_emit_cstring(":\n");
1608         }
1609
1610         for (i = 0; i < length; ++i) {
1611                 const ir_node *block = labels[i];
1612                 if (block == NULL)
1613                         block = targets[0];
1614                 be_emit_cstring("\t.long ");
1615                 be_gas_emit_block_name(block);
1616                 be_emit_char('\n');
1617                 be_emit_write_line();
1618         }
1619
1620         if (entity != NULL)
1621                 be_gas_emit_switch_section(GAS_SECTION_TEXT);
1622
1623         xfree(labels);
1624         xfree(targets);
1625 }
1626
1627 static void emit_global_asms(void)
1628 {
1629         size_t n = get_irp_n_asms();
1630         size_t i;
1631
1632         be_gas_emit_switch_section(GAS_SECTION_TEXT);
1633         for (i = 0; i < n; ++i) {
1634                 ident *asmtext = get_irp_asm(i);
1635
1636                 be_emit_cstring("#APP\n");
1637                 be_emit_write_line();
1638                 be_emit_irprintf("%I\n", asmtext);
1639                 be_emit_write_line();
1640                 be_emit_cstring("#NO_APP\n");
1641                 be_emit_write_line();
1642         }
1643 }
1644
1645 void be_gas_begin_compilation_unit(const be_main_env_t *env)
1646 {
1647         be_dwarf_open();
1648         be_dwarf_unit_begin(env->cup_name);
1649
1650         block_numbers = pmap_create();
1651         next_block_nr = 0;
1652
1653         emit_global_asms();
1654 }
1655
1656 void be_gas_end_compilation_unit(const be_main_env_t *env)
1657 {
1658         emit_global_decls(env);
1659
1660         pmap_destroy(block_numbers);
1661
1662         be_dwarf_unit_end();
1663         be_dwarf_close();
1664 }