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

   1 /*
   2  * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
   3  *
   4  * This file is part of libFirm.
   5  *
   6  * This file may be distributed and/or modified under the terms of the
   7  * GNU General Public License version 2 as published by the Free Software
   8  * Foundation and appearing in the file LICENSE.GPL included in the
   9  * packaging of this file.
  10  *
  11  * Licensees holding valid libFirm Professional Edition licenses may use
  12  * this file in accordance with the libFirm Commercial License.
  13  * Agreement provided with the Software.
  14  *
  15  * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
  16  * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  17  * PURPOSE.
  18  */
  19
  20 /**
  21  * @file
  22  * @brief       Dumps global variables and constants as gas assembler.
  23  * @author      Christian Wuerdig, Matthias Braun
  24  * @date        04.11.2005
  25  * @version     $Id$
  26  */
  27 #include "config.h"
  28
  29 #include "begnuas.h"
  30
  31 #include <stdlib.h>
  32 #include <string.h>
  33 #include <ctype.h>
  34 #include <assert.h>
  35
  36 #include "obst.h"
  37 #include "tv.h"
  38 #include "irnode.h"
  39 #include "irprog.h"
  40 #include "entity_t.h"
  41 #include "error.h"
  42
  43 #include "be_t.h"
  44 #include "beemitter.h"
  45 #include "be_dbgout.h"
  46
  47 /** by default, we generate assembler code for the Linux gas */
  48 object_file_format_t  be_gas_object_file_format = OBJECT_FILE_FORMAT_ELF;
  49 bool                  be_gas_emit_types         = true;
  50 char                  be_gas_elf_type_char      = '@';
  51
  52 static be_gas_section_t current_section = (be_gas_section_t) -1;
  53
  54 /**
  55  * An environment containing all needed dumper data.
  56  * Currently we create the file completely in memory first, then
  57  * write it to the disk. This is an artifact from the old C-generating backend
  58  * and even there NOT needed. So we might change it in the future.
  59  */
  60 typedef struct _be_gas_decl_env {
  61         be_gas_section_t     section;
  62         const be_main_env_t *main_env;
  63 } be_gas_decl_env_t;
  64
  65 static void emit_section_macho(be_gas_section_t section)
  66 {
  67         be_gas_section_t  base  = section & GAS_SECTION_TYPE_MASK;
  68         be_gas_section_t  flags = section & ~GAS_SECTION_TYPE_MASK;
  69         const char       *name;
  70
  71         if (current_section == section)
  72                 return;
  73         current_section = section;
  74
  75         /* shortforms */
  76         if (flags == 0) {
  77                 switch (base) {
  78                 case GAS_SECTION_TEXT:            name = "text";          break;
  79                 case GAS_SECTION_DATA:            name = "data";          break;
  80                 case GAS_SECTION_RODATA:          name = "const";         break;
  81                 case GAS_SECTION_BSS:             name = "data";          break;
  82                 case GAS_SECTION_CONSTRUCTORS:    name = "mod_init_func"; break;
  83                 case GAS_SECTION_DESTRUCTORS:     name = "mod_term_func"; break;
  84                 case GAS_SECTION_PIC_TRAMPOLINES: name = "section\t__IMPORT,__jump_table,symbol_stubs,self_modifying_code+pure_instructions,5"; break;
  85                 case GAS_SECTION_PIC_SYMBOLS:     name = "section\t__IMPORT,__pointers,non_lazy_symbol_pointers"; break;
  86                 case GAS_SECTION_CSTRING:         name = "cstring";       break;
  87                 default: panic("unsupported scetion type 0x%X", section);
  88                 }
  89                 be_emit_irprintf("\t.%s\n", name);
  90                 be_emit_write_line();
  91         } else if (flags & GAS_SECTION_FLAG_COMDAT) {
  92                 switch (base) {
  93                 case GAS_SECTION_TEXT:            name = "section __TEXT,__textcoal_nt,coalesced,pure_instructions"; break;
  94                 case GAS_SECTION_BSS:
  95                 case GAS_SECTION_DATA:            name = "section __DATA,__datacoal_nt,coalesced"; break;
  96                 case GAS_SECTION_RODATA:          name = "section __TEXT,__const_coal,coalesced"; break;
  97                 case GAS_SECTION_CSTRING:         name = "section __TEXT,__const_coal,coalesced"; break;
  98                 default: panic("unsupported scetion type 0x%X", section);
  99                 }
 100         } else {
 101                 panic("unsupported section type 0x%X\n", section);
 102         }
 103 }
 104
 105 static void emit_section(be_gas_section_t section, const ir_entity *entity)
 106 {
 107         be_gas_section_t base = section & GAS_SECTION_TYPE_MASK;
 108         be_gas_section_t flags = section & ~GAS_SECTION_TYPE_MASK;
 109         static const char *const basename[] = {
 110                 "text", "data", "rodata", "bss", "ctors", "dtors"
 111         };
 112         static const char *const type[] = {
 113                 "progbits", "progbits", "progbits", "nobits", "init_array", "fini_array"
 114         };
 115
 116         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 117                 emit_section_macho(section);
 118                 return;
 119         }
 120
 121         if (current_section == section && !(section & GAS_SECTION_FLAG_COMDAT))
 122                 return;
 123         current_section = section;
 124
 125         /* shortforms */
 126         if (flags == 0) {
 127                 switch (base) {
 128                 case GAS_SECTION_TEXT:
 129                         be_emit_cstring("\t.text\n");
 130                         be_emit_write_line();
 131                         return;
 132                 case GAS_SECTION_DATA:
 133                         be_emit_cstring("\t.data\n");
 134                         be_emit_write_line();
 135                         return;
 136                 case GAS_SECTION_RODATA:
 137                         be_emit_cstring("\t.section\t.rodata\n");
 138                         be_emit_write_line();
 139                         return;
 140                 case GAS_SECTION_BSS:
 141                         be_emit_cstring("\t.bss\n");
 142                         be_emit_write_line();
 143                         return;
 144                 default:
 145                         break;
 146                 }
 147         }
 148
 149         assert(base < sizeof(basename)/sizeof(basename[0]));
 150         be_emit_cstring("\t.section\t.");
 151         /* section name */
 152         if (flags & GAS_SECTION_FLAG_TLS)
 153                 be_emit_char('t');
 154         be_emit_string(basename[base]);
 155         if (flags & GAS_SECTION_FLAG_COMDAT) {
 156                 be_emit_char('.');
 157                 be_gas_emit_entity(entity);
 158         }
 159
 160         /* section flags */
 161         be_emit_cstring(",\"");
 162         if (be_gas_object_file_format != OBJECT_FILE_FORMAT_COFF)
 163                 be_emit_char('a');
 164         if (base == GAS_SECTION_TEXT)
 165                 be_emit_char('x');
 166         if (base != GAS_SECTION_RODATA && base != GAS_SECTION_TEXT)
 167                 be_emit_char('w');
 168         if (flags & GAS_SECTION_FLAG_TLS)
 169                 be_emit_char('T');
 170         if (flags & GAS_SECTION_FLAG_COMDAT)
 171                 be_emit_char('G');
 172         /* section type */
 173         if (be_gas_object_file_format != OBJECT_FILE_FORMAT_COFF) {
 174                 be_emit_cstring("\",");
 175                 be_emit_char(be_gas_elf_type_char);
 176                 be_emit_string(type[base]);
 177         }
 178
 179         if (flags & GAS_SECTION_FLAG_COMDAT) {
 180                 be_emit_char(',');
 181                 be_gas_emit_entity(entity);
 182                 be_emit_cstring(",comdat");
 183         }
 184         be_emit_char('\n');
 185         be_emit_write_line();
 186 }
 187
 188 void be_gas_emit_switch_section(be_gas_section_t section)
 189 {
 190         /* you have to produce a switch_section call with entity manually
 191          * for comdat sections */
 192         assert( !(section & GAS_SECTION_FLAG_COMDAT));
 193
 194         emit_section(section, NULL);
 195 }
 196
 197 static tarval *get_initializer_tarval(const ir_initializer_t *initializer)
 198 {
 199         if (initializer->kind == IR_INITIALIZER_TARVAL)
 200                 return initializer->tarval.value;
 201         if (initializer->kind == IR_INITIALIZER_CONST) {
 202                 ir_node *node = initializer->consti.value;
 203                 if (is_Const(node)) {
 204                         return get_Const_tarval(node);
 205                 }
 206         }
 207         return get_tarval_undefined();
 208 }
 209
 210 static int initializer_is_string_const(const ir_initializer_t *initializer)
 211 {
 212         size_t i, len;
 213         int found_printable = 0;
 214
 215         if (initializer->kind != IR_INITIALIZER_COMPOUND)
 216                 return 0;
 217
 218         len = initializer->compound.n_initializers;
 219         if (len < 1)
 220                 return 0;
 221         for (i = 0; i < len; ++i) {
 222                 int               c;
 223                 tarval           *tv;
 224                 ir_mode          *mode;
 225                 ir_initializer_t *sub_initializer
 226                         = initializer->compound.initializers[i];
 227
 228                 tv = get_initializer_tarval(sub_initializer);
 229                 if (!tarval_is_constant(tv))
 230                         return 0;
 231
 232                 mode = get_tarval_mode(tv);
 233                 if (!mode_is_int(mode) || get_mode_size_bits(mode) != 8)
 234                         return 0;
 235
 236                 c = get_tarval_long(tv);
 237                 if (isgraph(c) || isspace(c))
 238                         found_printable = 1;
 239                 else if (c != 0)
 240                         return 0;
 241
 242                 if (i == len - 1 && c != '\0')
 243                         return 0;
 244         }
 245
 246         return found_printable;
 247 }
 248
 249 static bool initializer_is_null(const ir_initializer_t *initializer)
 250 {
 251         switch (initializer->kind) {
 252         case IR_INITIALIZER_NULL:
 253                 return true;
 254         case IR_INITIALIZER_TARVAL: {
 255                 tarval *tv = initializer->tarval.value;
 256                 return tarval_is_null(tv);
 257         }
 258         case IR_INITIALIZER_CONST: {
 259                 ir_node *value = initializer->consti.value;
 260                 if (!is_Const(value))
 261                         return false;
 262                 return is_Const_null(value);
 263         }
 264         case IR_INITIALIZER_COMPOUND: {
 265                 size_t i;
 266                 for (i = 0; i < initializer->compound.n_initializers; ++i) {
 267                         ir_initializer_t *subinitializer
 268                                 = initializer->compound.initializers[i];
 269                         if (!initializer_is_null(subinitializer))
 270                                 return false;
 271                 }
 272                 return true;
 273         }
 274         }
 275         panic("invalid initializer in initializer_is_null");
 276 }
 277
 278 /**
 279  * Determine if an entity is a string constant
 280  * @param ent The entity
 281  * @return 1 if it is a string constant, 0 otherwise
 282  */
 283 static int entity_is_string_const(const ir_entity *ent)
 284 {
 285         ir_type *type, *element_type;
 286         ir_mode *mode;
 287         int i, c, n;
 288
 289         type = get_entity_type(ent);
 290
 291         /* if it's an array */
 292         if (!is_Array_type(type))
 293                 return 0;
 294
 295         element_type = get_array_element_type(type);
 296
 297         /* and the array's element type is primitive */
 298         if (!is_Primitive_type(element_type))
 299                 return 0;
 300
 301         /* and the mode of the element type is an int of
 302          * the same size as the byte mode */
 303         mode = get_type_mode(element_type);
 304         if (!mode_is_int(mode) || get_mode_size_bits(mode) != 8)
 305                 return 0;
 306
 307         if (ent->initializer != NULL) {
 308                 return initializer_is_string_const(ent->initializer);
 309         } else if (entity_has_compound_ent_values(ent)) {
 310                 int found_printable = 0;
 311                 /* if it contains only printable chars and a 0 at the end */
 312                 n = get_compound_ent_n_values(ent);
 313                 for (i = 0; i < n; ++i) {
 314                         ir_node *irn = get_compound_ent_value(ent, i);
 315                         if (! is_Const(irn))
 316                                 return 0;
 317
 318                         c = (int) get_tarval_long(get_Const_tarval(irn));
 319
 320                         if (isgraph(c) || isspace(c))
 321                                 found_printable = 1;
 322                         else if (c != 0)
 323                                 return 0;
 324
 325                         if (i == n - 1 && c != '\0')
 326                                 return 0;
 327                 }
 328                 return found_printable;
 329         }
 330
 331         return 0;
 332 }
 333
 334 static bool entity_is_null(const ir_entity *entity)
 335 {
 336         if (entity->initializer != NULL) {
 337                 return initializer_is_null(entity->initializer);
 338         } else if (entity_has_compound_ent_values(entity)) {
 339                 /* I'm too lazy to implement this case as compound graph paths will be
 340                  * remove anyway in the future */
 341                 return false;
 342         }
 343         /* uninitialized, NULL is fine */
 344         return true;
 345 }
 346
 347 static bool is_comdat(const ir_entity *entity)
 348 {
 349         ir_linkage linkage = get_entity_linkage(entity);
 350         return (linkage & IR_LINKAGE_MERGE)
 351                 && (linkage & IR_LINKAGE_GARBAGE_COLLECT);
 352 }
 353
 354 static be_gas_section_t determine_basic_section(const ir_entity *entity)
 355 {
 356         ir_linkage linkage;
 357
 358         if (is_method_entity(entity))
 359                 return GAS_SECTION_TEXT;
 360
 361         linkage = get_entity_linkage(entity);
 362         if (linkage & IR_LINKAGE_CONSTANT) {
 363                 /* mach-o is the only one with a cstring section */
 364                 if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O
 365                                 && entity_is_string_const(entity))
 366                         return GAS_SECTION_CSTRING;
 367
 368                 return GAS_SECTION_RODATA;
 369         }
 370         if (entity_is_null(entity))
 371                 return GAS_SECTION_BSS;
 372
 373         return GAS_SECTION_DATA;
 374 }
 375
 376 static be_gas_section_t determine_section(be_gas_decl_env_t *env,
 377                                           const ir_entity *entity)
 378 {
 379         ir_type *owner = get_entity_owner(entity);
 380
 381         if (owner == get_segment_type(IR_SEGMENT_GLOBAL)) {
 382                 be_gas_section_t section = determine_basic_section(entity);
 383                 if (is_comdat(entity))
 384                         section |= GAS_SECTION_FLAG_COMDAT;
 385                 return section;
 386         } else if (env != NULL && owner == env->main_env->pic_symbols_type) {
 387                 return GAS_SECTION_PIC_SYMBOLS;
 388         } else if (env != NULL && owner == env->main_env->pic_trampolines_type) {
 389                 return GAS_SECTION_PIC_TRAMPOLINES;
 390         } else if (owner == get_segment_type(IR_SEGMENT_CONSTRUCTORS)) {
 391                 return GAS_SECTION_CONSTRUCTORS;
 392         } else if (owner == get_segment_type(IR_SEGMENT_DESTRUCTORS)) {
 393                 return GAS_SECTION_DESTRUCTORS;
 394         } else if (owner == get_segment_type(IR_SEGMENT_THREAD_LOCAL)) {
 395                 be_gas_section_t section = determine_basic_section(entity);
 396                 if (is_comdat(entity))
 397                         section |= GAS_SECTION_FLAG_COMDAT;
 398
 399                 return section | GAS_SECTION_FLAG_TLS;
 400         }
 401
 402         /* the java frontend keeps some functions inside classes */
 403         if (is_Class_type(owner)) {
 404                 return determine_basic_section(entity);
 405         }
 406
 407         panic("Couldn't determine section for %+F?!?", entity);
 408 }
 409
 410 static void emit_weak(const ir_entity *entity)
 411 {
 412         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 413                 be_emit_cstring("\t.weak_reference ");
 414         } else {
 415                 be_emit_cstring("\t.weak ");
 416         }
 417         be_gas_emit_entity(entity);
 418         be_emit_char('\n');
 419         be_emit_write_line();
 420 }
 421
 422 static void emit_visibility(const ir_entity *entity)
 423 {
 424         ir_linkage linkage = get_entity_linkage(entity);
 425
 426         if (get_entity_linkage(entity) & IR_LINKAGE_WEAK) {
 427                 emit_weak(entity);
 428                 /* Note: .weak seems to imply .globl so no need to output .globl */
 429         } else if (get_entity_visibility(entity) == ir_visibility_default) {
 430                 be_emit_cstring(".globl ");
 431                 be_gas_emit_entity(entity);
 432                 be_emit_char('\n');
 433                 be_emit_write_line();
 434         }
 435
 436         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O
 437                         && (linkage & IR_LINKAGE_HIDDEN_USER)) {
 438                 be_emit_cstring("\t.no_dead_strip ");
 439                 be_gas_emit_entity(entity);
 440                 be_emit_char('\n');
 441                 be_emit_write_line();
 442         }
 443 }
 444
 445 void be_gas_emit_function_prolog(const ir_entity *entity, unsigned po2alignment)
 446 {
 447         be_gas_section_t section = determine_section(NULL, entity);
 448         emit_section(section, entity);
 449
 450         /* write the begin line (makes the life easier for scripts parsing the
 451          * assembler) */
 452         be_emit_write_line();
 453         be_emit_cstring("# -- Begin  ");
 454         be_gas_emit_entity(entity);
 455         be_emit_char('\n');
 456         be_emit_write_line();
 457
 458         if (po2alignment > 0) {
 459                 const char *fill_byte = "";
 460                 unsigned    maximum_skip = (1 << po2alignment) - 1;
 461                 /* gcc fills space between function with 0x90... */
 462                 if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 463                         fill_byte = "0x90";
 464                 }
 465                 be_emit_cstring("\t.p2align ");
 466                 be_emit_irprintf("%u,%s,%u\n", po2alignment, fill_byte, maximum_skip);
 467                 be_emit_write_line();
 468         }
 469         emit_visibility(entity);
 470
 471         switch (be_gas_object_file_format) {
 472         case OBJECT_FILE_FORMAT_ELF:
 473                 be_emit_cstring("\t.type\t");
 474                 be_gas_emit_entity(entity);
 475                 be_emit_cstring(", ");
 476                 be_emit_char(be_gas_elf_type_char);
 477                 be_emit_cstring("function\n");
 478                 be_emit_write_line();
 479                 break;
 480         case OBJECT_FILE_FORMAT_COFF:
 481                 be_emit_cstring("\t.def\t");
 482                 be_gas_emit_entity(entity);
 483                 be_emit_cstring(";");
 484                 if (get_entity_visibility(entity) == ir_visibility_local) {
 485                         be_emit_cstring("\t.scl\t3;");
 486                 } else {
 487                         be_emit_cstring("\t.scl\t2;");
 488                 }
 489                 be_emit_cstring("\t.type\t32;\t.endef\n");
 490                 be_emit_write_line();
 491                 break;
 492         case OBJECT_FILE_FORMAT_MACH_O:
 493                 break;
 494         }
 495         be_gas_emit_entity(entity);
 496         be_emit_cstring(":\n");
 497         be_emit_write_line();
 498 }
 499
 500 void be_gas_emit_function_epilog(const ir_entity *entity)
 501 {
 502         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_ELF) {
 503                 be_emit_cstring("\t.size\t");
 504                 be_gas_emit_entity(entity);
 505                 be_emit_cstring(", .-");
 506                 be_gas_emit_entity(entity);
 507                 be_emit_char('\n');
 508                 be_emit_write_line();
 509         }
 510
 511         be_emit_cstring("# -- End  ");
 512         be_gas_emit_entity(entity);
 513         be_emit_char('\n');
 514         be_emit_write_line();
 515 }
 516
 517 /************************************************************************/
 518
 519 /**
 520  * Output a tarval.
 521  *
 522  * @param tv     the tarval
 523  * @param bytes  the width of the tarvals value in bytes
 524  */
 525 static void emit_arith_tarval(tarval *tv, int bytes)
 526 {
 527         switch (bytes) {
 528         case 1:
 529                 be_emit_irprintf("0x%02x", get_tarval_sub_bits(tv, 0));
 530                 return;
 531
 532         case 2:
 533                 be_emit_irprintf("0x%02x%02x", get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 534                 return;
 535
 536         case 4:
 537                 be_emit_irprintf("0x%02x%02x%02x%02x",
 538                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 539                 return;
 540
 541         case 8:
 542                 be_emit_irprintf("0x%02x%02x%02x%02x%02x%02x%02x%02x",
 543                         get_tarval_sub_bits(tv, 7), get_tarval_sub_bits(tv, 6), get_tarval_sub_bits(tv, 5), get_tarval_sub_bits(tv, 4),
 544                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 545                 return;
 546
 547         case 12:
 548                 /* Beware: Mixed endian output!  One little endian number emitted as
 549                  * three longs.  Each long initializer is written in big endian. */
 550                 be_emit_irprintf(
 551                         "\t.long\t0x%02x%02x%02x%02x\n"
 552                         "\t.long\t0x%02x%02x%02x%02x\n"
 553                         "\t.long\t0x%02x%02x%02x%02x",
 554                         get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
 555                         get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0),
 556                         get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
 557                         get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
 558                         get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
 559                         get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8)
 560                 );
 561                 return;
 562
 563         case 16:
 564                 /* Beware: Mixed endian output!  One little endian number emitted as
 565                  * three longs.  Each long initializer is written in big endian. */
 566                 be_emit_irprintf(
 567                         "\t.long\t0x%02x%02x%02x%02x\n"
 568                         "\t.long\t0x%02x%02x%02x%02x\n"
 569                         "\t.long\t0x%02x%02x%02x%02x\n"
 570                         "\t.long\t0x%02x%02x%02x%02x",
 571                         get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
 572                         get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0),
 573                         get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
 574                         get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
 575                         get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
 576                         get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8),
 577                         get_tarval_sub_bits(tv, 15), get_tarval_sub_bits(tv, 14),
 578                         get_tarval_sub_bits(tv, 13), get_tarval_sub_bits(tv, 12)
 579                 );
 580                 return;
 581         }
 582
 583         panic("Can't dump a tarval with %d bytes", bytes);
 584 }
 585
 586 /**
 587  * Return the label prefix for labeled instructions.
 588  */
 589 const char *be_gas_insn_label_prefix(void)
 590 {
 591         return ".LE";
 592 }
 593
 594 /**
 595  * Return the tarval of an atomic initializer.
 596  *
 597  * @param init  a node representing the initializer (on the const code irg)
 598  *
 599  * @return the tarval
 600  */
 601 static tarval *get_atomic_init_tv(ir_node *init)
 602 {
 603         for (;;) {
 604                 ir_mode *mode = get_irn_mode(init);
 605
 606                 switch (get_irn_opcode(init)) {
 607
 608                 case iro_Cast:
 609                         init = get_Cast_op(init);
 610                         continue;
 611
 612                 case iro_Conv:
 613                         init = get_Conv_op(init);
 614                         continue;
 615
 616                 case iro_Const:
 617                         return get_Const_tarval(init);
 618
 619                 case iro_SymConst:
 620                         switch (get_SymConst_kind(init)) {
 621                         case symconst_type_size:
 622                                 return new_tarval_from_long(get_type_size_bytes(get_SymConst_type(init)), mode);
 623
 624                         case symconst_type_align:
 625                                 return new_tarval_from_long(get_type_alignment_bytes(get_SymConst_type(init)), mode);
 626
 627                         case symconst_ofs_ent:
 628                                 return new_tarval_from_long(get_entity_offset(get_SymConst_entity(init)), mode);
 629
 630                         case symconst_enum_const:
 631                                 return get_enumeration_value(get_SymConst_enum(init));
 632
 633                         default:
 634                                 return NULL;
 635                         }
 636
 637                 default:
 638                         return NULL;
 639                 }
 640         }
 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 do_emit_atomic_init(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         tarval *tv;
 654         ir_entity *ent;
 655
 656         init = skip_Id(init);
 657
 658         switch (get_irn_opcode(init)) {
 659         case iro_Cast:
 660                 do_emit_atomic_init(env, get_Cast_op(init));
 661                 return;
 662
 663         case iro_Conv:
 664                 do_emit_atomic_init(env, get_Conv_op(init));
 665                 return;
 666
 667         case iro_Const:
 668                 tv = get_Const_tarval(init);
 669
 670                 /* it's a 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                 do_emit_atomic_init(env, get_Add_left(init));
 709                 be_emit_cstring(" + ");
 710                 do_emit_atomic_init(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                 do_emit_atomic_init(env, get_Sub_left(init));
 718                 be_emit_cstring(" - ");
 719                 do_emit_atomic_init(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                 do_emit_atomic_init(env, get_Mul_left(init));
 727                 be_emit_cstring(" * ");
 728                 do_emit_atomic_init(env, get_Mul_right(init));
 729                 return;
 730
 731         case iro_Unknown:
 732                 be_emit_cstring("0");
 733                 return;
 734
 735         default:
 736                 panic("emit_atomic_init(): 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:
 749                 be_emit_cstring("\t.byte\t");
 750                 break;
 751
 752         case 2:
 753                 be_emit_cstring("\t.short\t");
 754                 break;
 755
 756         case 4:
 757                 be_emit_cstring("\t.long\t");
 758                 break;
 759
 760         case 8:
 761                 be_emit_cstring("\t.quad\t");
 762                 break;
 763
 764         case 10:
 765         case 12:
 766         case 16: /* Note: .octa does not work on mac */
 767                 /* handled in arith */
 768                 break;
 769
 770         default:
 771                 panic("Try to dump a type with %u bytes", (unsigned)size);
 772         }
 773 }
 774
 775 /**
 776  * Emit an atomic value.
 777  *
 778  * @param env   the gas output environment
 779  * @param init  a node representing the atomic value (on the const code irg)
 780  */
 781 static void emit_atomic_init(be_gas_decl_env_t *env, ir_node *init)
 782 {
 783         ir_mode *mode = get_irn_mode(init);
 784         int bytes     = get_mode_size_bytes(mode);
 785
 786         emit_size_type(bytes);
 787         do_emit_atomic_init(env, init);
 788         be_emit_char('\n');
 789         be_emit_write_line();
 790 }
 791
 792 /************************************************************************/
 793 /* Routines to dump global variables                                    */
 794 /************************************************************************/
 795
 796 /**
 797  * Dump a string constant.
 798  * No checks are made!!
 799  *
 800  * @param ent  The entity to dump.
 801  */
 802 static void emit_string_cst(const ir_entity *ent)
 803 {
 804         int      i, len;
 805         int      output_len;
 806         ir_type *type;
 807         int      type_size;
 808         int      remaining_space;
 809
 810         len        = get_compound_ent_n_values(ent);
 811         output_len = len;
 812         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 813                 be_emit_cstring("\t.ascii \"");
 814         } else {
 815                 be_emit_cstring("\t.string \"");
 816                 output_len -= 1;
 817         }
 818
 819         for (i = 0; i < output_len; ++i) {
 820                 ir_node *irn;
 821                 int c;
 822
 823                 irn = get_compound_ent_value(ent, i);
 824                 c = (int) get_tarval_long(get_Const_tarval(irn));
 825
 826                 switch (c) {
 827                 case '"' : be_emit_cstring("\\\""); break;
 828                 case '\n': be_emit_cstring("\\n"); break;
 829                 case '\r': be_emit_cstring("\\r"); break;
 830                 case '\t': be_emit_cstring("\\t"); break;
 831                 case '\\': be_emit_cstring("\\\\"); break;
 832                 default  :
 833                         if (isprint(c))
 834                                 be_emit_char(c);
 835                         else
 836                                 be_emit_irprintf("\\%o", c);
 837                         break;
 838                 }
 839         }
 840         be_emit_cstring("\"\n");
 841         be_emit_write_line();
 842
 843         type            = get_entity_type(ent);
 844         type_size       = get_type_size_bytes(type);
 845         remaining_space = type_size - len;
 846         assert(remaining_space >= 0);
 847         if (remaining_space > 0) {
 848                 be_emit_irprintf("\t.space\t%d\n", remaining_space);
 849         }
 850 }
 851
 852 static void emit_string_initializer(const ir_initializer_t *initializer)
 853 {
 854         size_t i, len;
 855
 856         len = initializer->compound.n_initializers;
 857         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 858                 be_emit_cstring("\t.ascii \"");
 859         } else {
 860                 be_emit_cstring("\t.string \"");
 861                 len -= 1;
 862         }
 863
 864         for (i = 0; i < len; ++i) {
 865                 const ir_initializer_t *sub_initializer
 866                         = get_initializer_compound_value(initializer, i);
 867
 868                 tarval *tv = get_initializer_tarval(sub_initializer);
 869                 int     c  = get_tarval_long(tv);
 870
 871                 switch (c) {
 872                 case '"' : be_emit_cstring("\\\""); break;
 873                 case '\n': be_emit_cstring("\\n"); break;
 874                 case '\r': be_emit_cstring("\\r"); break;
 875                 case '\t': be_emit_cstring("\\t"); break;
 876                 case '\\': be_emit_cstring("\\\\"); break;
 877                 default  :
 878                         if (isprint(c))
 879                                 be_emit_char(c);
 880                         else
 881                                 be_emit_irprintf("\\%o", c);
 882                         break;
 883                 }
 884         }
 885         be_emit_cstring("\"\n");
 886         be_emit_write_line();
 887 }
 888
 889 enum normal_or_bitfield_kind {
 890         NORMAL = 0,
 891         TARVAL,
 892         BITFIELD
 893 };
 894
 895 typedef struct {
 896         enum normal_or_bitfield_kind kind;
 897         union {
 898                 ir_node       *value;
 899                 tarval        *tarval;
 900                 unsigned char  bf_val;
 901         } v;
 902 } normal_or_bitfield;
 903
 904 static int is_type_variable_size(ir_type *type)
 905 {
 906         (void) type;
 907         /* TODO */
 908         return 0;
 909 }
 910
 911 static size_t get_initializer_size(const ir_initializer_t *initializer,
 912                                    ir_type *type)
 913 {
 914         switch (get_initializer_kind(initializer)) {
 915         case IR_INITIALIZER_TARVAL:
 916                 assert(get_tarval_mode(get_initializer_tarval_value(initializer)) == get_type_mode(type));
 917                 return get_type_size_bytes(type);
 918         case IR_INITIALIZER_CONST:
 919         case IR_INITIALIZER_NULL:
 920                 return get_type_size_bytes(type);
 921         case IR_INITIALIZER_COMPOUND:
 922                 if (!is_type_variable_size(type)) {
 923                         return get_type_size_bytes(type);
 924                 } else {
 925                         unsigned n_entries
 926                                 = get_initializer_compound_n_entries(initializer);
 927                         unsigned i;
 928                         unsigned initializer_size = get_type_size_bytes(type);
 929                         for (i = 0; i < n_entries; ++i) {
 930                                 ir_entity *entity = get_compound_member(type, i);
 931                                 ir_type   *type   = get_entity_type(entity);
 932
 933                                 const ir_initializer_t *sub_initializer
 934                                         = get_initializer_compound_value(initializer, i);
 935
 936                                 unsigned offset = get_entity_offset(entity);
 937                                 unsigned size   = get_initializer_size(sub_initializer, type);
 938
 939                                 if (offset + size > initializer_size) {
 940                                         initializer_size = offset + size;
 941                                 }
 942                         }
 943                         return initializer_size;
 944                 }
 945         }
 946
 947         panic("found invalid initializer");
 948 }
 949
 950 #ifndef NDEBUG
 951 static normal_or_bitfield *glob_vals;
 952 static size_t              max_vals;
 953 #endif
 954
 955 static void emit_bitfield(normal_or_bitfield *vals, size_t offset_bits,
 956                           const ir_initializer_t *initializer, ir_type *type)
 957 {
 958         unsigned char  last_bits = 0;
 959         ir_mode       *mode      = get_type_mode(type);
 960         tarval        *tv        = NULL;
 961         unsigned char  curr_bits;
 962         int            value_len;
 963         int            j;
 964
 965         switch (get_initializer_kind(initializer)) {
 966         case IR_INITIALIZER_NULL:
 967                 return;
 968         case IR_INITIALIZER_TARVAL:
 969                 tv = get_initializer_tarval_value(initializer);
 970                 break;
 971         case IR_INITIALIZER_CONST: {
 972                 ir_node *node = get_initializer_const_value(initializer);
 973                 if (!is_Const(node)) {
 974                         panic("bitfield initializer not a Const node");
 975                 }
 976                 tv = get_Const_tarval(node);
 977                 break;
 978         }
 979         case IR_INITIALIZER_COMPOUND:
 980                 panic("bitfield initializer is compound");
 981         }
 982         if (tv == NULL) {
 983                 panic("Couldn't get numeric value for bitfield initializer");
 984         }
 985         tv = tarval_convert_to(tv, get_type_mode(type));
 986
 987         /* normalize offset */
 988         vals        += offset_bits >> 3;
 989         offset_bits &= 7;
 990         value_len    = get_mode_size_bits(mode);
 991
 992         /* combine bits with existing bits */
 993         for (j = 0; value_len + (int) offset_bits > 0; ++j) {
 994                 assert((size_t) (vals - glob_vals) + j < max_vals);
 995                 assert(vals[j].kind == BITFIELD ||
 996                                 (vals[j].kind == NORMAL && vals[j].v.value == NULL));
 997                 vals[j].kind = BITFIELD;
 998                 curr_bits    = get_tarval_sub_bits(tv, j);
 999                 vals[j].v.bf_val
1000                         |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
1001                 value_len -= 8;
1002                 last_bits = curr_bits;
1003         }
1004 }
1005
1006 static void emit_ir_initializer(normal_or_bitfield *vals,
1007                                 const ir_initializer_t *initializer,
1008                                 ir_type *type)
1009 {
1010         assert((size_t) (vals - glob_vals) < max_vals);
1011
1012         switch (get_initializer_kind(initializer)) {
1013         case IR_INITIALIZER_NULL:
1014                 return;
1015         case IR_INITIALIZER_TARVAL: {
1016                 size_t i;
1017
1018                 assert(vals->kind != BITFIELD);
1019                 vals->kind     = TARVAL;
1020                 vals->v.tarval = get_initializer_tarval_value(initializer);
1021                 assert(get_type_mode(type) == get_tarval_mode(vals->v.tarval));
1022                 for (i = 1; i < get_type_size_bytes(type); ++i) {
1023                         vals[i].kind    = NORMAL;
1024                         vals[i].v.value = NULL;
1025                 }
1026                 return;
1027         }
1028         case IR_INITIALIZER_CONST: {
1029                 size_t i;
1030
1031                 assert(vals->kind != BITFIELD);
1032                 vals->kind    = NORMAL;
1033                 vals->v.value = get_initializer_const_value(initializer);
1034                 for (i = 1; i < get_type_size_bytes(type); ++i) {
1035                         vals[i].kind    = NORMAL;
1036                         vals[i].v.value = NULL;
1037                 }
1038                 return;
1039         }
1040         case IR_INITIALIZER_COMPOUND: {
1041                 size_t i = 0;
1042                 size_t n = get_initializer_compound_n_entries(initializer);
1043
1044                 if (is_Array_type(type)) {
1045                         ir_type *element_type = get_array_element_type(type);
1046                         size_t   skip         = get_type_size_bytes(element_type);
1047                         size_t   alignment    = get_type_alignment_bytes(element_type);
1048                         size_t   misalign     = skip % alignment;
1049                         if (misalign != 0) {
1050                                 skip += alignment - misalign;
1051                         }
1052
1053                         for (i = 0; i < n; ++i) {
1054                                 ir_initializer_t *sub_initializer
1055                                         = get_initializer_compound_value(initializer, i);
1056
1057                                 emit_ir_initializer(vals, sub_initializer, element_type);
1058
1059                                 vals += skip;
1060                         }
1061                 } else {
1062                         size_t n_members, i;
1063                         assert(is_compound_type(type));
1064                         n_members = get_compound_n_members(type);
1065                         for (i = 0; i < n_members; ++i) {
1066                                 ir_entity        *member    = get_compound_member(type, i);
1067                                 size_t            offset    = get_entity_offset(member);
1068                                 ir_type          *subtype   = get_entity_type(member);
1069                                 ir_mode          *mode      = get_type_mode(subtype);
1070                                 ir_initializer_t *sub_initializer;
1071
1072                                 assert(i < get_initializer_compound_n_entries(initializer));
1073                                 sub_initializer
1074                                         = get_initializer_compound_value(initializer, i);
1075
1076                                 if (mode != NULL) {
1077                                         size_t offset_bits
1078                                                 = get_entity_offset_bits_remainder(member);
1079                                         size_t value_len   = get_mode_size_bits(mode);
1080
1081                                         if (offset_bits != 0 ||
1082                                                 (value_len != 8 && value_len != 16 && value_len != 32
1083                                                  && value_len != 64)) {
1084                                                 emit_bitfield(&vals[offset], offset_bits,
1085                                                               sub_initializer, subtype);
1086                                                 continue;
1087                                         }
1088                                 }
1089
1090                                 emit_ir_initializer(&vals[offset], sub_initializer, subtype);
1091                         }
1092                 }
1093
1094                 return;
1095         }
1096         }
1097         panic("invalid ir_initializer kind found");
1098 }
1099
1100 static void emit_initializer(be_gas_decl_env_t *env, const ir_entity *entity)
1101 {
1102         const ir_initializer_t *initializer = entity->initializer;
1103         ir_type                *type;
1104         normal_or_bitfield     *vals;
1105         size_t                  size;
1106         size_t                  k;
1107
1108         if (initializer_is_string_const(initializer)) {
1109                 emit_string_initializer(initializer);
1110                 return;
1111         }
1112
1113         type = get_entity_type(entity);
1114         size = get_initializer_size(initializer, type);
1115
1116         if (size == 0)
1117                 return;
1118
1119         /*
1120          * In the worst case, every initializer allocates one byte.
1121          * Moreover, initializer might be big, do not allocate on stack.
1122          */
1123         vals = XMALLOCNZ(normal_or_bitfield, size);
1124
1125 #ifndef NDEBUG
1126         glob_vals = vals;
1127         max_vals  = size;
1128 #endif
1129
1130         emit_ir_initializer(vals, initializer, type);
1131
1132         /* now write values sorted */
1133         for (k = 0; k < size; ) {
1134                 int space     = 0;
1135                 int elem_size = 1;
1136                 if (vals[k].kind == NORMAL) {
1137                         if (vals[k].v.value != NULL) {
1138                                 emit_atomic_init(env, vals[k].v.value);
1139                                 elem_size = get_mode_size_bytes(get_irn_mode(vals[k].v.value));
1140                         } else {
1141                                 elem_size = 0;
1142                         }
1143                 } else if (vals[k].kind == TARVAL) {
1144                         tarval *tv   = vals[k].v.tarval;
1145                         size_t  size = get_mode_size_bytes(get_tarval_mode(tv));
1146
1147                         assert(tv != NULL);
1148
1149                         elem_size = size;
1150                         emit_size_type(size);
1151                         emit_arith_tarval(tv, size);
1152                         be_emit_char('\n');
1153                         be_emit_write_line();
1154                 } else {
1155                         assert(vals[k].kind == BITFIELD);
1156                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
1157                         be_emit_write_line();
1158                 }
1159
1160                 k += elem_size;
1161                 while (k < size && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
1162                         ++space;
1163                         ++k;
1164                 }
1165
1166                 /* a gap */
1167                 if (space > 0) {
1168                         be_emit_irprintf("\t.space\t%d\n", space);
1169                         be_emit_write_line();
1170                 }
1171         }
1172         xfree(vals);
1173 }
1174
1175 static void emit_compound_graph_init(be_gas_decl_env_t *env,
1176                                      const ir_entity *ent)
1177 {
1178         normal_or_bitfield *vals;
1179         int i, j, n;
1180         unsigned k, last_ofs;
1181
1182         if (entity_is_string_const(ent)) {
1183                 emit_string_cst(ent);
1184                 return;
1185         }
1186
1187         n = get_compound_ent_n_values(ent);
1188
1189         /* Find the initializer size. Sorrily gcc support a nasty feature:
1190            The last field of a compound may be a flexible array. This allows
1191            initializers bigger than the type size. */
1192         last_ofs = get_type_size_bytes(get_entity_type(ent));
1193         for (i = 0; i < n; ++i) {
1194                 unsigned offset         = get_compound_ent_value_offset_bytes(ent, i);
1195                 unsigned bits_remainder = get_compound_ent_value_offset_bit_remainder(ent, i);
1196                 ir_node  *value         = get_compound_ent_value(ent, i);
1197                 unsigned value_len      = get_mode_size_bits(get_irn_mode(value));
1198
1199                 offset += (value_len + bits_remainder + 7) >> 3;
1200
1201                 if (offset > last_ofs) {
1202                         last_ofs = offset;
1203                 }
1204         }
1205
1206         /*
1207          * In the worst case, every initializer allocates one byte.
1208          * Moreover, initializer might be big, do not allocate on stack.
1209          */
1210         vals = XMALLOCNZ(normal_or_bitfield, last_ofs);
1211
1212         /* collect the values and store them at the offsets */
1213         for (i = 0; i < n; ++i) {
1214                 unsigned offset      = get_compound_ent_value_offset_bytes(ent, i);
1215                 int      offset_bits = get_compound_ent_value_offset_bit_remainder(ent, i);
1216                 ir_node  *value      = get_compound_ent_value(ent, i);
1217                 int      value_len   = get_mode_size_bits(get_irn_mode(value));
1218
1219                 assert(offset_bits >= 0);
1220
1221                 if (offset_bits != 0 ||
1222                                 (value_len != 8 && value_len != 16 && value_len != 32 && value_len != 64)) {
1223                         tarval *tv = get_atomic_init_tv(value);
1224                         unsigned char curr_bits, last_bits = 0;
1225                         if (tv == NULL) {
1226                                 panic("Couldn't get numeric value for bitfield initializer '%s'",
1227                                                 get_entity_ld_name(ent));
1228                         }
1229                         /* normalize offset */
1230                         offset += offset_bits >> 3;
1231                         offset_bits &= 7;
1232
1233                         for (j = 0; value_len + offset_bits > 0; ++j) {
1234                                 assert(offset + j < last_ofs);
1235                                 assert(vals[offset + j].kind == BITFIELD || vals[offset + j].v.value == NULL);
1236                                 vals[offset + j].kind = BITFIELD;
1237                                 curr_bits = get_tarval_sub_bits(tv, j);
1238                                 vals[offset + j].v.bf_val |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
1239                                 value_len -= 8;
1240                                 last_bits = curr_bits;
1241                         }
1242                 } else {
1243                         int i;
1244
1245                         assert(offset < last_ofs);
1246                         assert(vals[offset].kind == NORMAL);
1247                         for (i = 1; i < value_len / 8; ++i) {
1248                                 assert(vals[offset + i].v.value == NULL);
1249                         }
1250                         vals[offset].v.value = value;
1251                 }
1252         }
1253
1254         /* now write them sorted */
1255         for (k = 0; k < last_ofs; ) {
1256                 int space = 0, skip = 0;
1257                 if (vals[k].kind == NORMAL) {
1258                         if (vals[k].v.value != NULL) {
1259                                 emit_atomic_init(env, vals[k].v.value);
1260                                 skip = get_mode_size_bytes(get_irn_mode(vals[k].v.value)) - 1;
1261                         } else {
1262                                 space = 1;
1263                         }
1264                 } else {
1265                         assert(vals[k].kind == BITFIELD);
1266                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
1267                 }
1268
1269                 ++k;
1270                 while (k < last_ofs && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
1271                         ++space;
1272                         ++k;
1273                 }
1274                 space -= skip;
1275                 assert(space >= 0);
1276
1277                 /* a gap */
1278                 if (space > 0) {
1279                         be_emit_irprintf("\t.space\t%d\n", space);
1280                         be_emit_write_line();
1281                 }
1282         }
1283         xfree(vals);
1284 }
1285
1286 static void emit_align(unsigned p2alignment)
1287 {
1288         be_emit_irprintf("\t.p2align\t%u\n", log2_floor(p2alignment));
1289         be_emit_write_line();
1290 }
1291
1292 static unsigned get_effective_entity_alignment(const ir_entity *entity)
1293 {
1294         unsigned alignment = get_entity_alignment(entity);
1295         if (alignment == 0) {
1296                 ir_type *type = get_entity_type(entity);
1297                 alignment     = get_type_alignment_bytes(type);
1298         }
1299         return alignment;
1300 }
1301
1302 static void emit_common(const ir_entity *entity)
1303 {
1304         unsigned size      = get_type_size_bytes(get_entity_type(entity));
1305         unsigned alignment = get_effective_entity_alignment(entity);
1306
1307         if (get_entity_linkage(entity) & IR_LINKAGE_WEAK) {
1308                 emit_weak(entity);
1309         }
1310
1311         switch (be_gas_object_file_format) {
1312         case OBJECT_FILE_FORMAT_MACH_O:
1313                 be_emit_cstring("\t.comm ");
1314                 be_gas_emit_entity(entity);
1315                 be_emit_irprintf(",%u,%u\n", size, log2_floor(alignment));
1316                 be_emit_write_line();
1317                 return;
1318         case OBJECT_FILE_FORMAT_ELF:
1319                 be_emit_cstring("\t.comm ");
1320                 be_gas_emit_entity(entity);
1321                 be_emit_irprintf(",%u,%u\n", size, alignment);
1322                 be_emit_write_line();
1323                 return;
1324         case OBJECT_FILE_FORMAT_COFF:
1325                 be_emit_cstring("\t.comm ");
1326                 be_gas_emit_entity(entity);
1327                 be_emit_irprintf(",%u # %u\n", size, alignment);
1328                 be_emit_write_line();
1329                 return;
1330         }
1331         panic("invalid object file format");
1332 }
1333
1334 static void emit_local_common(const ir_entity *entity)
1335 {
1336         unsigned size      = get_type_size_bytes(get_entity_type(entity));
1337         unsigned alignment = get_effective_entity_alignment(entity);
1338
1339         if (get_entity_linkage(entity) & IR_LINKAGE_WEAK) {
1340                 emit_weak(entity);
1341         }
1342
1343         switch (be_gas_object_file_format) {
1344         case OBJECT_FILE_FORMAT_MACH_O:
1345                 be_emit_cstring("\t.lcomm ");
1346                 be_gas_emit_entity(entity);
1347                 be_emit_irprintf(",%u,%u\n", size, log2_floor(alignment));
1348                 be_emit_write_line();
1349                 return;
1350         case OBJECT_FILE_FORMAT_ELF:
1351                 be_emit_cstring("\t.local ");
1352                 be_gas_emit_entity(entity);
1353                 be_emit_cstring("\n");
1354                 be_emit_write_line();
1355                 be_emit_cstring("\t.comm ");
1356                 be_gas_emit_entity(entity);
1357                 be_emit_irprintf(",%u,%u\n", size, alignment);
1358                 be_emit_write_line();
1359                 return;
1360         case OBJECT_FILE_FORMAT_COFF:
1361                 be_emit_cstring("\t.lcomm ");
1362                 be_gas_emit_entity(entity);
1363                 be_emit_irprintf(",%u # %u\n", size, alignment);
1364                 be_emit_write_line();
1365                 return;
1366         }
1367         panic("invalid object file format");
1368 }
1369
1370 static void emit_indirect_symbol(const ir_entity *entity, be_gas_section_t section)
1371 {
1372         /* we can only do PIC code on macho so far */
1373         assert(be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O);
1374
1375         be_gas_emit_entity(entity);
1376         be_emit_cstring(":\n");
1377         be_emit_write_line();
1378         be_emit_cstring("\t.indirect_symbol ");
1379         be_emit_ident(get_entity_ident(entity));
1380         be_emit_char('\n');
1381         be_emit_write_line();
1382         if (section == GAS_SECTION_PIC_TRAMPOLINES) {
1383                 be_emit_cstring("\thlt ; hlt ; hlt ; hlt ; hlt\n");
1384                 be_emit_write_line();
1385         } else {
1386                 assert(section == GAS_SECTION_PIC_SYMBOLS);
1387                 be_emit_cstring("\t.long 0\n");
1388                 be_emit_write_line();
1389         }
1390 }
1391
1392 char const *be_gas_get_private_prefix(void)
1393 {
1394         return
1395                 be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O ? "L" :
1396                 ".L";
1397 }
1398
1399 void be_gas_emit_entity(const ir_entity *entity)
1400 {
1401         if (entity->type == firm_code_type) {
1402                 ir_label_t label = get_entity_label(entity);
1403                 be_emit_irprintf("%s_%lu", be_gas_get_private_prefix(), label);
1404                 return;
1405         }
1406
1407         if (get_entity_visibility(entity) == ir_visibility_private) {
1408                 be_emit_string(be_gas_get_private_prefix());
1409         }
1410         be_emit_ident(get_entity_ld_ident(entity));
1411 }
1412
1413 void be_gas_emit_block_name(const ir_node *block)
1414 {
1415         if (has_Block_entity(block)) {
1416                 ir_entity *entity = get_Block_entity(block);
1417                 be_gas_emit_entity(entity);
1418         } else {
1419                 be_emit_irprintf("%s%ld", be_gas_get_private_prefix(), get_irn_node_nr(block));
1420         }
1421 }
1422
1423 /**
1424  * Dump a global entity.
1425  *
1426  * @param env  the gas output environment
1427  * @param ent  the entity to be dumped
1428  */
1429 static void emit_global(be_gas_decl_env_t *env, const ir_entity *entity)
1430 {
1431         ir_type          *type       = get_entity_type(entity);
1432         ident            *ld_ident   = get_entity_ld_ident(entity);
1433         unsigned          alignment  = get_effective_entity_alignment(entity);
1434         be_gas_section_t  section    = determine_section(env, entity);
1435         ir_visibility     visibility = get_entity_visibility(entity);
1436         ir_linkage        linkage    = get_entity_linkage(entity);
1437
1438         /* block labels are already emittet in the code */
1439         if (type == firm_code_type)
1440                 return;
1441
1442         /* we already emitted all methods. Except for the trampolines which
1443          * the assembler/linker generates */
1444         if (is_Method_type(type) && section != GAS_SECTION_PIC_TRAMPOLINES) {
1445                 /* functions with graph are already emitted with
1446                  * be_gas_emit_function_prolog */
1447                 if (get_entity_irg(entity) == NULL) {
1448                         emit_visibility(entity);
1449                 }
1450                 return;
1451         }
1452
1453         be_dbg_variable(entity);
1454
1455         if (section == GAS_SECTION_BSS) {
1456                 ir_visibility visibility = get_entity_visibility(entity);
1457
1458                 switch (visibility) {
1459                 case ir_visibility_local:
1460                 case ir_visibility_private:
1461                         emit_local_common(entity);
1462                         return;
1463                 case ir_visibility_default:
1464                         if (linkage & IR_LINKAGE_MERGE) {
1465                                 emit_common(entity);
1466                                 return;
1467                         }
1468                         break;
1469                 case ir_visibility_external:
1470                         if (linkage & IR_LINKAGE_MERGE)
1471                                 panic("merge link semantic not supported for extern entities");
1472                         break;
1473                 }
1474         }
1475
1476         emit_visibility(entity);
1477         if (visibility == ir_visibility_external) {
1478                 /* nothing to do for externally defined values */
1479                 return;
1480         }
1481
1482         if (!is_po2(alignment))
1483                 panic("alignment not a power of 2");
1484
1485         emit_section(section, entity);
1486
1487         if (section == GAS_SECTION_PIC_TRAMPOLINES
1488                         || section == GAS_SECTION_PIC_SYMBOLS) {
1489                 emit_indirect_symbol(entity, section);
1490                 return;
1491         }
1492
1493         /* alignment */
1494         if (alignment > 1) {
1495                 emit_align(alignment);
1496         }
1497         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_ELF
1498                         && be_gas_emit_types) {
1499                 be_emit_cstring("\t.type\t");
1500                 be_gas_emit_entity(entity);
1501                 be_emit_cstring(", ");
1502                 be_emit_char(be_gas_elf_type_char);
1503                 be_emit_cstring("object\n\t.size\t");\
1504                 be_gas_emit_entity(entity);
1505                 be_emit_irprintf(", %u\n", get_type_size_bytes(type));
1506         }
1507
1508         if (get_id_str(ld_ident)[0] != '\0') {
1509             be_gas_emit_entity(entity);
1510                 be_emit_cstring(":\n");
1511                 be_emit_write_line();
1512         }
1513
1514         if (entity_is_null(entity)) {
1515                 be_emit_irprintf("\t.space %u\n", get_type_size_bytes(type));
1516                 be_emit_write_line();
1517         } else if (entity_has_compound_ent_values(entity)) {
1518                 emit_compound_graph_init(env, entity);
1519         } else {
1520                 assert(entity->initializer != NULL);
1521                 emit_initializer(env, entity);
1522         }
1523 }
1524
1525 /**
1526  * Dumps declarations of global variables and the initialization code.
1527  *
1528  * @param gt                a global like type, either the global or the TLS one
1529  * @param env               an environment
1530  */
1531 static void be_gas_emit_globals(ir_type *gt, be_gas_decl_env_t *env)
1532 {
1533         int i, n = get_compound_n_members(gt);
1534
1535         for (i = 0; i < n; i++) {
1536                 ir_entity *ent = get_compound_member(gt, i);
1537                 emit_global(env, ent);
1538         }
1539 }
1540
1541 /************************************************************************/
1542
1543 /* Generate all entities. */
1544 void be_gas_emit_decls(const be_main_env_t *main_env)
1545 {
1546         be_gas_decl_env_t env;
1547         memset(&env, 0, sizeof(env));
1548
1549         /* dump global type */
1550         env.main_env = main_env;
1551         env.section  = (be_gas_section_t) -1;
1552
1553         be_gas_emit_globals(get_glob_type(), &env);
1554         be_gas_emit_globals(get_tls_type(), &env);
1555         be_gas_emit_globals(get_segment_type(IR_SEGMENT_CONSTRUCTORS), &env);
1556         be_gas_emit_globals(get_segment_type(IR_SEGMENT_DESTRUCTORS), &env);
1557         be_gas_emit_globals(main_env->pic_symbols_type, &env);
1558         be_gas_emit_globals(main_env->pic_trampolines_type, &env);
1559
1560         /**
1561          * ".subsections_via_symbols marks object files which are OK to divide
1562          * their section contents into individual blocks".
1563          * From my understanding this means no label points in the middle of an
1564          * object which we want to address as a whole. Firm code should be fine
1565          * with this.
1566          */
1567         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
1568                 be_emit_cstring("\t.subsections_via_symbols\n");
1569                 be_emit_write_line();
1570         }
1571 }