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         be_emit_cstring("\",");
 173         be_emit_char(be_gas_elf_type_char);
 174         be_emit_string(type[base]);
 175
 176         if (flags & GAS_SECTION_FLAG_COMDAT) {
 177                 be_emit_char(',');
 178                 be_gas_emit_entity(entity);
 179                 be_emit_cstring(",comdat");
 180         }
 181         be_emit_char('\n');
 182         be_emit_write_line();
 183 }
 184
 185 void be_gas_emit_switch_section(be_gas_section_t section)
 186 {
 187         /* you have to produce a switch_section call with entity manually
 188          * for comdat sections */
 189         assert( !(section & GAS_SECTION_FLAG_COMDAT));
 190
 191         emit_section(section, NULL);
 192 }
 193
 194 static tarval *get_initializer_tarval(const ir_initializer_t *initializer)
 195 {
 196         if (initializer->kind == IR_INITIALIZER_TARVAL)
 197                 return initializer->tarval.value;
 198         if (initializer->kind == IR_INITIALIZER_CONST) {
 199                 ir_node *node = initializer->consti.value;
 200                 if (is_Const(node)) {
 201                         return get_Const_tarval(node);
 202                 }
 203         }
 204         return get_tarval_undefined();
 205 }
 206
 207 static int initializer_is_string_const(const ir_initializer_t *initializer)
 208 {
 209         size_t i, len;
 210         int found_printable = 0;
 211
 212         if (initializer->kind != IR_INITIALIZER_COMPOUND)
 213                 return 0;
 214
 215         len = initializer->compound.n_initializers;
 216         if (len < 1)
 217                 return 0;
 218         for (i = 0; i < len; ++i) {
 219                 int               c;
 220                 tarval           *tv;
 221                 ir_mode          *mode;
 222                 ir_initializer_t *sub_initializer
 223                         = initializer->compound.initializers[i];
 224
 225                 tv = get_initializer_tarval(sub_initializer);
 226                 if (!tarval_is_constant(tv))
 227                         return 0;
 228
 229                 mode = get_tarval_mode(tv);
 230                 if (!mode_is_int(mode) || get_mode_size_bits(mode) != 8)
 231                         return 0;
 232
 233                 c = get_tarval_long(tv);
 234                 if (isgraph(c) || isspace(c))
 235                         found_printable = 1;
 236                 else if (c != 0)
 237                         return 0;
 238
 239                 if (i == len - 1 && c != '\0')
 240                         return 0;
 241         }
 242
 243         return found_printable;
 244 }
 245
 246 static bool initializer_is_null(const ir_initializer_t *initializer)
 247 {
 248         switch (initializer->kind) {
 249         case IR_INITIALIZER_NULL:
 250                 return true;
 251         case IR_INITIALIZER_TARVAL: {
 252                 tarval *tv = initializer->tarval.value;
 253                 return tarval_is_null(tv);
 254         }
 255         case IR_INITIALIZER_CONST: {
 256                 ir_node *value = initializer->consti.value;
 257                 if (!is_Const(value))
 258                         return false;
 259                 return is_Const_null(value);
 260         }
 261         case IR_INITIALIZER_COMPOUND: {
 262                 size_t i;
 263                 for (i = 0; i < initializer->compound.n_initializers; ++i) {
 264                         ir_initializer_t *subinitializer
 265                                 = initializer->compound.initializers[i];
 266                         if (!initializer_is_null(subinitializer))
 267                                 return false;
 268                 }
 269                 return true;
 270         }
 271         }
 272         panic("invalid initializer in initializer_is_null");
 273 }
 274
 275 /**
 276  * Determine if an entity is a string constant
 277  * @param ent The entity
 278  * @return 1 if it is a string constant, 0 otherwise
 279  */
 280 static int entity_is_string_const(const ir_entity *ent)
 281 {
 282         ir_type *type, *element_type;
 283         ir_mode *mode;
 284         int i, c, n;
 285
 286         type = get_entity_type(ent);
 287
 288         /* if it's an array */
 289         if (!is_Array_type(type))
 290                 return 0;
 291
 292         element_type = get_array_element_type(type);
 293
 294         /* and the array's element type is primitive */
 295         if (!is_Primitive_type(element_type))
 296                 return 0;
 297
 298         /* and the mode of the element type is an int of
 299          * the same size as the byte mode */
 300         mode = get_type_mode(element_type);
 301         if (!mode_is_int(mode) || get_mode_size_bits(mode) != 8)
 302                 return 0;
 303
 304         if (ent->initializer != NULL) {
 305                 return initializer_is_string_const(ent->initializer);
 306         } else if (entity_has_compound_ent_values(ent)) {
 307                 int found_printable = 0;
 308                 /* if it contains only printable chars and a 0 at the end */
 309                 n = get_compound_ent_n_values(ent);
 310                 for (i = 0; i < n; ++i) {
 311                         ir_node *irn = get_compound_ent_value(ent, i);
 312                         if (! is_Const(irn))
 313                                 return 0;
 314
 315                         c = (int) get_tarval_long(get_Const_tarval(irn));
 316
 317                         if (isgraph(c) || isspace(c))
 318                                 found_printable = 1;
 319                         else if (c != 0)
 320                                 return 0;
 321
 322                         if (i == n - 1 && c != '\0')
 323                                 return 0;
 324                 }
 325                 return found_printable;
 326         }
 327
 328         return 0;
 329 }
 330
 331 static bool entity_is_null(const ir_entity *entity)
 332 {
 333         if (entity->initializer != NULL) {
 334                 return initializer_is_null(entity->initializer);
 335         } else if (entity_has_compound_ent_values(entity)) {
 336                 /* I'm too lazy to implement this case as compound graph paths will be
 337                  * remove anyway in the future */
 338         }
 339         /* uninitialized, NULL is fine */
 340         return true;
 341 }
 342
 343 static bool is_comdat(const ir_entity *entity)
 344 {
 345         ir_linkage linkage = get_entity_linkage(entity);
 346         return (linkage & IR_LINKAGE_MERGE)
 347                 && (linkage & IR_LINKAGE_GARBAGE_COLLECT);
 348 }
 349
 350 static be_gas_section_t determine_basic_section(const ir_entity *entity)
 351 {
 352         ir_linkage linkage;
 353
 354         if (is_method_entity(entity))
 355                 return GAS_SECTION_TEXT;
 356
 357         linkage = get_entity_linkage(entity);
 358         if (linkage & IR_LINKAGE_CONSTANT) {
 359                 /* mach-o is the only one with a cstring section */
 360                 if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O
 361                                 && entity_is_string_const(entity))
 362                         return GAS_SECTION_CSTRING;
 363
 364                 return GAS_SECTION_RODATA;
 365         }
 366         if (entity_is_null(entity))
 367                 return GAS_SECTION_BSS;
 368
 369         return GAS_SECTION_DATA;
 370 }
 371
 372 static be_gas_section_t determine_section(be_gas_decl_env_t *env,
 373                                           const ir_entity *entity)
 374 {
 375         ir_type *owner = get_entity_owner(entity);
 376
 377         if (owner == get_segment_type(IR_SEGMENT_GLOBAL)) {
 378                 be_gas_section_t section = determine_basic_section(entity);
 379                 if (is_comdat(entity))
 380                         section |= GAS_SECTION_FLAG_COMDAT;
 381                 return section;
 382         } else if (env != NULL && owner == env->main_env->pic_symbols_type) {
 383                 return GAS_SECTION_PIC_SYMBOLS;
 384         } else if (env != NULL && owner == env->main_env->pic_trampolines_type) {
 385                 return GAS_SECTION_PIC_TRAMPOLINES;
 386         } else if (owner == get_segment_type(IR_SEGMENT_CONSTRUCTORS)) {
 387                 return GAS_SECTION_CONSTRUCTORS;
 388         } else if (owner == get_segment_type(IR_SEGMENT_DESTRUCTORS)) {
 389                 return GAS_SECTION_DESTRUCTORS;
 390         } else if (owner == get_segment_type(IR_SEGMENT_THREAD_LOCAL)) {
 391                 be_gas_section_t section = determine_basic_section(entity);
 392                 if (is_comdat(entity))
 393                         section |= GAS_SECTION_FLAG_COMDAT;
 394
 395                 return section | GAS_SECTION_FLAG_TLS;
 396         }
 397
 398         panic("Couldn't determine section for %+F?!?", entity);
 399 }
 400
 401 static void emit_weak(const ir_entity *entity)
 402 {
 403         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 404                 be_emit_cstring("\t.weak_reference ");
 405         } else {
 406                 be_emit_cstring("\t.weak ");
 407         }
 408         be_gas_emit_entity(entity);
 409         be_emit_char('\n');
 410         be_emit_write_line();
 411 }
 412
 413 static void emit_visibility(const ir_entity *entity)
 414 {
 415         ir_linkage linkage = get_entity_linkage(entity);
 416
 417         if (get_entity_linkage(entity) & IR_LINKAGE_WEAK) {
 418                 emit_weak(entity);
 419                 /* Note: .weak seems to imply .globl so no need to output .globl */
 420         } else if (get_entity_visibility(entity) == ir_visibility_default) {
 421                 be_emit_cstring(".globl ");
 422                 be_gas_emit_entity(entity);
 423                 be_emit_char('\n');
 424                 be_emit_write_line();
 425         }
 426
 427         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O
 428                         && (linkage & IR_LINKAGE_HIDDEN_USER)) {
 429                 be_emit_cstring("\t.no_dead_strip ");
 430                 be_gas_emit_entity(entity);
 431                 be_emit_char('\n');
 432                 be_emit_write_line();
 433         }
 434 }
 435
 436 void be_gas_emit_function_prolog(const ir_entity *entity, unsigned po2alignment)
 437 {
 438         be_gas_section_t section = determine_section(NULL, entity);
 439         emit_section(section, entity);
 440
 441         /* write the begin line (makes the life easier for scripts parsing the
 442          * assembler) */
 443         be_emit_write_line();
 444         be_emit_cstring("# -- Begin  ");
 445         be_gas_emit_entity(entity);
 446         be_emit_char('\n');
 447         be_emit_write_line();
 448
 449         if (po2alignment > 0) {
 450                 const char *fill_byte = "";
 451                 unsigned    maximum_skip = (1 << po2alignment) - 1;
 452                 /* gcc fills space between function with 0x90... */
 453                 if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 454                         fill_byte = "0x90";
 455                 }
 456                 be_emit_cstring("\t.p2align ");
 457                 be_emit_irprintf("%u,%s,%u\n", po2alignment, fill_byte, maximum_skip);
 458                 be_emit_write_line();
 459         }
 460         emit_visibility(entity);
 461
 462         switch (be_gas_object_file_format) {
 463         case OBJECT_FILE_FORMAT_ELF:
 464                 be_emit_cstring("\t.type\t");
 465                 be_gas_emit_entity(entity);
 466                 be_emit_cstring(", ");
 467                 be_emit_char(be_gas_elf_type_char);
 468                 be_emit_cstring("function\n");
 469                 be_emit_write_line();
 470                 break;
 471         case OBJECT_FILE_FORMAT_COFF:
 472                 be_emit_cstring("\t.def\t");
 473                 be_gas_emit_entity(entity);
 474                 be_emit_cstring(";");
 475                 if (get_entity_visibility(entity) == ir_visibility_local) {
 476                         be_emit_cstring("\t.scl\t3;");
 477                 } else {
 478                         be_emit_cstring("\t.scl\t2;");
 479                 }
 480                 be_emit_cstring("\t.type\t32;\t.endef\n");
 481                 be_emit_write_line();
 482                 break;
 483         case OBJECT_FILE_FORMAT_MACH_O:
 484                 break;
 485         }
 486         be_gas_emit_entity(entity);
 487         be_emit_cstring(":\n");
 488         be_emit_write_line();
 489 }
 490
 491 void be_gas_emit_function_epilog(const ir_entity *entity)
 492 {
 493         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_ELF) {
 494                 be_emit_cstring("\t.size\t");
 495                 be_gas_emit_entity(entity);
 496                 be_emit_cstring(", .-");
 497                 be_gas_emit_entity(entity);
 498                 be_emit_char('\n');
 499                 be_emit_write_line();
 500         }
 501
 502         be_emit_cstring("# -- End  ");
 503         be_gas_emit_entity(entity);
 504         be_emit_char('\n');
 505         be_emit_write_line();
 506 }
 507
 508 /************************************************************************/
 509
 510 /**
 511  * Output a tarval.
 512  *
 513  * @param tv     the tarval
 514  * @param bytes  the width of the tarvals value in bytes
 515  */
 516 static void emit_arith_tarval(tarval *tv, int bytes)
 517 {
 518         switch (bytes) {
 519         case 1:
 520                 be_emit_irprintf("0x%02x", get_tarval_sub_bits(tv, 0));
 521                 return;
 522
 523         case 2:
 524                 be_emit_irprintf("0x%02x%02x", get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 525                 return;
 526
 527         case 4:
 528                 be_emit_irprintf("0x%02x%02x%02x%02x",
 529                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 530                 return;
 531
 532         case 8:
 533                 be_emit_irprintf("0x%02x%02x%02x%02x%02x%02x%02x%02x",
 534                         get_tarval_sub_bits(tv, 7), get_tarval_sub_bits(tv, 6), get_tarval_sub_bits(tv, 5), get_tarval_sub_bits(tv, 4),
 535                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 536                 return;
 537
 538         case 12:
 539                 /* Beware: Mixed endian output!  One little endian number emitted as
 540                  * three longs.  Each long initializer is written in big endian. */
 541                 be_emit_irprintf(
 542                         "\t.long\t0x%02x%02x%02x%02x\n"
 543                         "\t.long\t0x%02x%02x%02x%02x\n"
 544                         "\t.long\t0x%02x%02x%02x%02x",
 545                         get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
 546                         get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0),
 547                         get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
 548                         get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
 549                         get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
 550                         get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8)
 551                 );
 552                 return;
 553
 554         case 16:
 555                 /* Beware: Mixed endian output!  One little endian number emitted as
 556                  * three longs.  Each long initializer is written in big endian. */
 557                 be_emit_irprintf(
 558                         "\t.long\t0x%02x%02x%02x%02x\n"
 559                         "\t.long\t0x%02x%02x%02x%02x\n"
 560                         "\t.long\t0x%02x%02x%02x%02x\n"
 561                         "\t.long\t0x%02x%02x%02x%02x",
 562                         get_tarval_sub_bits(tv,  3), get_tarval_sub_bits(tv,  2),
 563                         get_tarval_sub_bits(tv,  1), get_tarval_sub_bits(tv,  0),
 564                         get_tarval_sub_bits(tv,  7), get_tarval_sub_bits(tv,  6),
 565                         get_tarval_sub_bits(tv,  5), get_tarval_sub_bits(tv,  4),
 566                         get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
 567                         get_tarval_sub_bits(tv,  9), get_tarval_sub_bits(tv,  8),
 568                         get_tarval_sub_bits(tv, 15), get_tarval_sub_bits(tv, 14),
 569                         get_tarval_sub_bits(tv, 13), get_tarval_sub_bits(tv, 12)
 570                 );
 571                 return;
 572         }
 573
 574         panic("Can't dump a tarval with %d bytes", bytes);
 575 }
 576
 577 /**
 578  * Return the label prefix for labeled instructions.
 579  */
 580 const char *be_gas_insn_label_prefix(void)
 581 {
 582         return ".LE";
 583 }
 584
 585 /**
 586  * Return the tarval of an atomic initializer.
 587  *
 588  * @param init  a node representing the initializer (on the const code irg)
 589  *
 590  * @return the tarval
 591  */
 592 static tarval *get_atomic_init_tv(ir_node *init)
 593 {
 594         for (;;) {
 595                 ir_mode *mode = get_irn_mode(init);
 596
 597                 switch (get_irn_opcode(init)) {
 598
 599                 case iro_Cast:
 600                         init = get_Cast_op(init);
 601                         continue;
 602
 603                 case iro_Conv:
 604                         init = get_Conv_op(init);
 605                         continue;
 606
 607                 case iro_Const:
 608                         return get_Const_tarval(init);
 609
 610                 case iro_SymConst:
 611                         switch (get_SymConst_kind(init)) {
 612                         case symconst_type_size:
 613                                 return new_tarval_from_long(get_type_size_bytes(get_SymConst_type(init)), mode);
 614
 615                         case symconst_type_align:
 616                                 return new_tarval_from_long(get_type_alignment_bytes(get_SymConst_type(init)), mode);
 617
 618                         case symconst_ofs_ent:
 619                                 return new_tarval_from_long(get_entity_offset(get_SymConst_entity(init)), mode);
 620
 621                         case symconst_enum_const:
 622                                 return get_enumeration_value(get_SymConst_enum(init));
 623
 624                         default:
 625                                 return NULL;
 626                         }
 627
 628                 default:
 629                         return NULL;
 630                 }
 631         }
 632 }
 633
 634 /**
 635  * Dump an atomic value.
 636  *
 637  * @param env   the gas output environment
 638  * @param init  a node representing the atomic value (on the const code irg)
 639  */
 640 static void do_emit_atomic_init(be_gas_decl_env_t *env, ir_node *init)
 641 {
 642         ir_mode *mode = get_irn_mode(init);
 643         int bytes     = get_mode_size_bytes(mode);
 644         tarval *tv;
 645         ir_entity *ent;
 646
 647         init = skip_Id(init);
 648
 649         switch (get_irn_opcode(init)) {
 650         case iro_Cast:
 651                 do_emit_atomic_init(env, get_Cast_op(init));
 652                 return;
 653
 654         case iro_Conv:
 655                 do_emit_atomic_init(env, get_Conv_op(init));
 656                 return;
 657
 658         case iro_Const:
 659                 tv = get_Const_tarval(init);
 660
 661                 /* it's a arithmetic value */
 662                 emit_arith_tarval(tv, bytes);
 663                 return;
 664
 665         case iro_SymConst:
 666                 switch (get_SymConst_kind(init)) {
 667                 case symconst_addr_name:
 668                         be_emit_ident(get_SymConst_name(init));
 669                         break;
 670
 671                 case symconst_addr_ent:
 672                         ent = get_SymConst_entity(init);
 673                         be_gas_emit_entity(ent);
 674                         break;
 675
 676                 case symconst_ofs_ent:
 677                         ent = get_SymConst_entity(init);
 678                         be_emit_irprintf("%d", get_entity_offset(ent));
 679                         break;
 680
 681                 case symconst_type_size:
 682                         be_emit_irprintf("%u", get_type_size_bytes(get_SymConst_type(init)));
 683                         break;
 684
 685                 case symconst_type_align:
 686                         be_emit_irprintf("%u", get_type_alignment_bytes(get_SymConst_type(init)));
 687                         break;
 688
 689                 case symconst_enum_const:
 690                         tv = get_enumeration_value(get_SymConst_enum(init));
 691                         emit_arith_tarval(tv, bytes);
 692                         break;
 693
 694                 default:
 695                         assert(!"emit_atomic_init(): don't know how to init from this SymConst");
 696                 }
 697                 return;
 698
 699         case iro_Add:
 700                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 701                         panic("Constant must be int or pointer for '+' to work");
 702                 }
 703                 do_emit_atomic_init(env, get_Add_left(init));
 704                 be_emit_cstring(" + ");
 705                 do_emit_atomic_init(env, get_Add_right(init));
 706                 return;
 707
 708         case iro_Sub:
 709                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 710                         panic("Constant must be int or pointer for '-' to work");
 711                 }
 712                 do_emit_atomic_init(env, get_Sub_left(init));
 713                 be_emit_cstring(" - ");
 714                 do_emit_atomic_init(env, get_Sub_right(init));
 715                 return;
 716
 717         case iro_Mul:
 718                 if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 719                         panic("Constant must be int or pointer for '*' to work");
 720                 }
 721                 do_emit_atomic_init(env, get_Mul_left(init));
 722                 be_emit_cstring(" * ");
 723                 do_emit_atomic_init(env, get_Mul_right(init));
 724                 return;
 725
 726         case iro_Unknown:
 727                 be_emit_cstring("0");
 728                 return;
 729
 730         default:
 731                 panic("emit_atomic_init(): unsupported IR-node %+F", init);
 732         }
 733 }
 734
 735 /**
 736  * Dumps the type for given size (.byte, .long, ...)
 737  *
 738  * @param size  the size in bytes
 739  */
 740 static void emit_size_type(size_t size)
 741 {
 742         switch (size) {
 743         case 1:
 744                 be_emit_cstring("\t.byte\t");
 745                 break;
 746
 747         case 2:
 748                 be_emit_cstring("\t.short\t");
 749                 break;
 750
 751         case 4:
 752                 be_emit_cstring("\t.long\t");
 753                 break;
 754
 755         case 8:
 756                 be_emit_cstring("\t.quad\t");
 757                 break;
 758
 759         case 10:
 760         case 12:
 761         case 16: /* Note: .octa does not work on mac */
 762                 /* handled in arith */
 763                 break;
 764
 765         default:
 766                 panic("Try to dump a type with %u bytes", (unsigned)size);
 767         }
 768 }
 769
 770 /**
 771  * Emit an atomic value.
 772  *
 773  * @param env   the gas output environment
 774  * @param init  a node representing the atomic value (on the const code irg)
 775  */
 776 static void emit_atomic_init(be_gas_decl_env_t *env, ir_node *init)
 777 {
 778         ir_mode *mode = get_irn_mode(init);
 779         int bytes     = get_mode_size_bytes(mode);
 780
 781         emit_size_type(bytes);
 782         do_emit_atomic_init(env, init);
 783         be_emit_char('\n');
 784         be_emit_write_line();
 785 }
 786
 787 /************************************************************************/
 788 /* Routines to dump global variables                                    */
 789 /************************************************************************/
 790
 791 /**
 792  * Dump a string constant.
 793  * No checks are made!!
 794  *
 795  * @param ent  The entity to dump.
 796  */
 797 static void emit_string_cst(const ir_entity *ent)
 798 {
 799         int      i, len;
 800         int      output_len;
 801         ir_type *type;
 802         int      type_size;
 803         int      remaining_space;
 804
 805         len        = get_compound_ent_n_values(ent);
 806         output_len = len;
 807         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 808                 be_emit_cstring("\t.ascii \"");
 809         } else {
 810                 be_emit_cstring("\t.string \"");
 811                 output_len -= 1;
 812         }
 813
 814         for (i = 0; i < output_len; ++i) {
 815                 ir_node *irn;
 816                 int c;
 817
 818                 irn = get_compound_ent_value(ent, i);
 819                 c = (int) get_tarval_long(get_Const_tarval(irn));
 820
 821                 switch (c) {
 822                 case '"' : be_emit_cstring("\\\""); break;
 823                 case '\n': be_emit_cstring("\\n"); break;
 824                 case '\r': be_emit_cstring("\\r"); break;
 825                 case '\t': be_emit_cstring("\\t"); break;
 826                 case '\\': be_emit_cstring("\\\\"); break;
 827                 default  :
 828                         if (isprint(c))
 829                                 be_emit_char(c);
 830                         else
 831                                 be_emit_irprintf("\\%o", c);
 832                         break;
 833                 }
 834         }
 835         be_emit_cstring("\"\n");
 836         be_emit_write_line();
 837
 838         type            = get_entity_type(ent);
 839         type_size       = get_type_size_bytes(type);
 840         remaining_space = type_size - len;
 841         assert(remaining_space >= 0);
 842         if (remaining_space > 0) {
 843                 be_emit_irprintf("\t.space\t%d\n", remaining_space);
 844         }
 845 }
 846
 847 static void emit_string_initializer(const ir_initializer_t *initializer)
 848 {
 849         size_t i, len;
 850
 851         len = initializer->compound.n_initializers;
 852         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
 853                 be_emit_cstring("\t.ascii \"");
 854         } else {
 855                 be_emit_cstring("\t.string \"");
 856                 len -= 1;
 857         }
 858
 859         for (i = 0; i < len; ++i) {
 860                 const ir_initializer_t *sub_initializer
 861                         = get_initializer_compound_value(initializer, i);
 862
 863                 tarval *tv = get_initializer_tarval(sub_initializer);
 864                 int     c  = get_tarval_long(tv);
 865
 866                 switch (c) {
 867                 case '"' : be_emit_cstring("\\\""); break;
 868                 case '\n': be_emit_cstring("\\n"); break;
 869                 case '\r': be_emit_cstring("\\r"); break;
 870                 case '\t': be_emit_cstring("\\t"); break;
 871                 case '\\': be_emit_cstring("\\\\"); break;
 872                 default  :
 873                         if (isprint(c))
 874                                 be_emit_char(c);
 875                         else
 876                                 be_emit_irprintf("\\%o", c);
 877                         break;
 878                 }
 879         }
 880         be_emit_cstring("\"\n");
 881         be_emit_write_line();
 882 }
 883
 884 enum normal_or_bitfield_kind {
 885         NORMAL = 0,
 886         TARVAL,
 887         BITFIELD
 888 };
 889
 890 typedef struct {
 891         enum normal_or_bitfield_kind kind;
 892         union {
 893                 ir_node       *value;
 894                 tarval        *tarval;
 895                 unsigned char  bf_val;
 896         } v;
 897 } normal_or_bitfield;
 898
 899 static int is_type_variable_size(ir_type *type)
 900 {
 901         (void) type;
 902         /* TODO */
 903         return 0;
 904 }
 905
 906 static size_t get_initializer_size(const ir_initializer_t *initializer,
 907                                    ir_type *type)
 908 {
 909         switch (get_initializer_kind(initializer)) {
 910         case IR_INITIALIZER_TARVAL:
 911                 assert(get_tarval_mode(get_initializer_tarval_value(initializer)) == get_type_mode(type));
 912                 return get_type_size_bytes(type);
 913         case IR_INITIALIZER_CONST:
 914         case IR_INITIALIZER_NULL:
 915                 return get_type_size_bytes(type);
 916         case IR_INITIALIZER_COMPOUND:
 917                 if (!is_type_variable_size(type)) {
 918                         return get_type_size_bytes(type);
 919                 } else {
 920                         unsigned n_entries
 921                                 = get_initializer_compound_n_entries(initializer);
 922                         unsigned i;
 923                         unsigned initializer_size = get_type_size_bytes(type);
 924                         for (i = 0; i < n_entries; ++i) {
 925                                 ir_entity *entity = get_compound_member(type, i);
 926                                 ir_type   *type   = get_entity_type(entity);
 927
 928                                 const ir_initializer_t *sub_initializer
 929                                         = get_initializer_compound_value(initializer, i);
 930
 931                                 unsigned offset = get_entity_offset(entity);
 932                                 unsigned size   = get_initializer_size(sub_initializer, type);
 933
 934                                 if (offset + size > initializer_size) {
 935                                         initializer_size = offset + size;
 936                                 }
 937                         }
 938                         return initializer_size;
 939                 }
 940         }
 941
 942         panic("found invalid initializer");
 943 }
 944
 945 #ifndef NDEBUG
 946 static normal_or_bitfield *glob_vals;
 947 static size_t              max_vals;
 948 #endif
 949
 950 static void emit_bitfield(normal_or_bitfield *vals, size_t offset_bits,
 951                           const ir_initializer_t *initializer, ir_type *type)
 952 {
 953         unsigned char  last_bits = 0;
 954         ir_mode       *mode      = get_type_mode(type);
 955         tarval        *tv        = NULL;
 956         unsigned char  curr_bits;
 957         int            value_len;
 958         int            j;
 959
 960         switch (get_initializer_kind(initializer)) {
 961         case IR_INITIALIZER_NULL:
 962                 return;
 963         case IR_INITIALIZER_TARVAL:
 964                 tv = get_initializer_tarval_value(initializer);
 965                 break;
 966         case IR_INITIALIZER_CONST: {
 967                 ir_node *node = get_initializer_const_value(initializer);
 968                 if (!is_Const(node)) {
 969                         panic("bitfield initializer not a Const node");
 970                 }
 971                 tv = get_Const_tarval(node);
 972                 break;
 973         }
 974         case IR_INITIALIZER_COMPOUND:
 975                 panic("bitfield initializer is compound");
 976         }
 977         if (tv == NULL) {
 978                 panic("Couldn't get numeric value for bitfield initializer");
 979         }
 980         tv = tarval_convert_to(tv, get_type_mode(type));
 981
 982         /* normalize offset */
 983         vals        += offset_bits >> 3;
 984         offset_bits &= 7;
 985         value_len    = get_mode_size_bits(mode);
 986
 987         /* combine bits with existing bits */
 988         for (j = 0; value_len + (int) offset_bits > 0; ++j) {
 989                 assert((size_t) (vals - glob_vals) + j < max_vals);
 990                 assert(vals[j].kind == BITFIELD ||
 991                                 (vals[j].kind == NORMAL && vals[j].v.value == NULL));
 992                 vals[j].kind = BITFIELD;
 993                 curr_bits    = get_tarval_sub_bits(tv, j);
 994                 vals[j].v.bf_val
 995                         |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
 996                 value_len -= 8;
 997                 last_bits = curr_bits;
 998         }
 999 }
1000
1001 static void emit_ir_initializer(normal_or_bitfield *vals,
1002                                 const ir_initializer_t *initializer,
1003                                 ir_type *type)
1004 {
1005         assert((size_t) (vals - glob_vals) < max_vals);
1006
1007         switch (get_initializer_kind(initializer)) {
1008         case IR_INITIALIZER_NULL:
1009                 return;
1010         case IR_INITIALIZER_TARVAL: {
1011                 size_t i;
1012
1013                 assert(vals->kind != BITFIELD);
1014                 vals->kind     = TARVAL;
1015                 vals->v.tarval = get_initializer_tarval_value(initializer);
1016                 assert(get_type_mode(type) == get_tarval_mode(vals->v.tarval));
1017                 for (i = 1; i < get_type_size_bytes(type); ++i) {
1018                         vals[i].kind    = NORMAL;
1019                         vals[i].v.value = NULL;
1020                 }
1021                 return;
1022         }
1023         case IR_INITIALIZER_CONST: {
1024                 size_t i;
1025
1026                 assert(vals->kind != BITFIELD);
1027                 vals->kind    = NORMAL;
1028                 vals->v.value = get_initializer_const_value(initializer);
1029                 for (i = 1; i < get_type_size_bytes(type); ++i) {
1030                         vals[i].kind    = NORMAL;
1031                         vals[i].v.value = NULL;
1032                 }
1033                 return;
1034         }
1035         case IR_INITIALIZER_COMPOUND: {
1036                 size_t i = 0;
1037                 size_t n = get_initializer_compound_n_entries(initializer);
1038
1039                 if (is_Array_type(type)) {
1040                         ir_type *element_type = get_array_element_type(type);
1041                         size_t   skip         = get_type_size_bytes(element_type);
1042                         size_t   alignment    = get_type_alignment_bytes(element_type);
1043                         size_t   misalign     = skip % alignment;
1044                         if (misalign != 0) {
1045                                 skip += alignment - misalign;
1046                         }
1047
1048                         for (i = 0; i < n; ++i) {
1049                                 ir_initializer_t *sub_initializer
1050                                         = get_initializer_compound_value(initializer, i);
1051
1052                                 emit_ir_initializer(vals, sub_initializer, element_type);
1053
1054                                 vals += skip;
1055                         }
1056                 } else {
1057                         size_t n_members, i;
1058                         assert(is_compound_type(type));
1059                         n_members = get_compound_n_members(type);
1060                         for (i = 0; i < n_members; ++i) {
1061                                 ir_entity        *member    = get_compound_member(type, i);
1062                                 size_t            offset    = get_entity_offset(member);
1063                                 ir_type          *subtype   = get_entity_type(member);
1064                                 ir_mode          *mode      = get_type_mode(subtype);
1065                                 ir_initializer_t *sub_initializer;
1066
1067                                 assert(i < get_initializer_compound_n_entries(initializer));
1068                                 sub_initializer
1069                                         = get_initializer_compound_value(initializer, i);
1070
1071                                 if (mode != NULL) {
1072                                         size_t offset_bits
1073                                                 = get_entity_offset_bits_remainder(member);
1074                                         size_t value_len   = get_mode_size_bits(mode);
1075
1076                                         if (offset_bits != 0 ||
1077                                                 (value_len != 8 && value_len != 16 && value_len != 32
1078                                                  && value_len != 64)) {
1079                                                 emit_bitfield(&vals[offset], offset_bits,
1080                                                               sub_initializer, subtype);
1081                                                 continue;
1082                                         }
1083                                 }
1084
1085                                 emit_ir_initializer(&vals[offset], sub_initializer, subtype);
1086                         }
1087                 }
1088
1089                 return;
1090         }
1091         }
1092         panic("invalid ir_initializer kind found");
1093 }
1094
1095 static void emit_initializer(be_gas_decl_env_t *env, const ir_entity *entity)
1096 {
1097         const ir_initializer_t *initializer = entity->initializer;
1098         ir_type                *type;
1099         normal_or_bitfield     *vals;
1100         size_t                  size;
1101         size_t                  k;
1102
1103         if (initializer_is_string_const(initializer)) {
1104                 emit_string_initializer(initializer);
1105                 return;
1106         }
1107
1108         type = get_entity_type(entity);
1109         size = get_initializer_size(initializer, type);
1110
1111         if (size == 0)
1112                 return;
1113
1114         /*
1115          * In the worst case, every initializer allocates one byte.
1116          * Moreover, initializer might be big, do not allocate on stack.
1117          */
1118         vals = XMALLOCNZ(normal_or_bitfield, size);
1119
1120 #ifndef NDEBUG
1121         glob_vals = vals;
1122         max_vals  = size;
1123 #endif
1124
1125         emit_ir_initializer(vals, initializer, type);
1126
1127         /* now write values sorted */
1128         for (k = 0; k < size; ) {
1129                 int space     = 0;
1130                 int elem_size = 1;
1131                 if (vals[k].kind == NORMAL) {
1132                         if (vals[k].v.value != NULL) {
1133                                 emit_atomic_init(env, vals[k].v.value);
1134                                 elem_size = get_mode_size_bytes(get_irn_mode(vals[k].v.value));
1135                         } else {
1136                                 elem_size = 0;
1137                         }
1138                 } else if (vals[k].kind == TARVAL) {
1139                         tarval *tv   = vals[k].v.tarval;
1140                         size_t  size = get_mode_size_bytes(get_tarval_mode(tv));
1141
1142                         assert(tv != NULL);
1143
1144                         elem_size = size;
1145                         emit_size_type(size);
1146                         emit_arith_tarval(tv, size);
1147                         be_emit_char('\n');
1148                         be_emit_write_line();
1149                 } else {
1150                         assert(vals[k].kind == BITFIELD);
1151                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
1152                         be_emit_write_line();
1153                 }
1154
1155                 k += elem_size;
1156                 while (k < size && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
1157                         ++space;
1158                         ++k;
1159                 }
1160
1161                 /* a gap */
1162                 if (space > 0) {
1163                         be_emit_irprintf("\t.space\t%d\n", space);
1164                         be_emit_write_line();
1165                 }
1166         }
1167         xfree(vals);
1168 }
1169
1170 static void emit_compound_graph_init(be_gas_decl_env_t *env,
1171                                      const ir_entity *ent)
1172 {
1173         normal_or_bitfield *vals;
1174         int i, j, n;
1175         unsigned k, last_ofs;
1176
1177         if (entity_is_string_const(ent)) {
1178                 emit_string_cst(ent);
1179                 return;
1180         }
1181
1182         n = get_compound_ent_n_values(ent);
1183
1184         /* Find the initializer size. Sorrily gcc support a nasty feature:
1185            The last field of a compound may be a flexible array. This allows
1186            initializers bigger than the type size. */
1187         last_ofs = get_type_size_bytes(get_entity_type(ent));
1188         for (i = 0; i < n; ++i) {
1189                 unsigned offset         = get_compound_ent_value_offset_bytes(ent, i);
1190                 unsigned bits_remainder = get_compound_ent_value_offset_bit_remainder(ent, i);
1191                 ir_node  *value         = get_compound_ent_value(ent, i);
1192                 unsigned value_len      = get_mode_size_bits(get_irn_mode(value));
1193
1194                 offset += (value_len + bits_remainder + 7) >> 3;
1195
1196                 if (offset > last_ofs) {
1197                         last_ofs = offset;
1198                 }
1199         }
1200
1201         /*
1202          * In the worst case, every initializer allocates one byte.
1203          * Moreover, initializer might be big, do not allocate on stack.
1204          */
1205         vals = XMALLOCNZ(normal_or_bitfield, last_ofs);
1206
1207         /* collect the values and store them at the offsets */
1208         for (i = 0; i < n; ++i) {
1209                 unsigned offset      = get_compound_ent_value_offset_bytes(ent, i);
1210                 int      offset_bits = get_compound_ent_value_offset_bit_remainder(ent, i);
1211                 ir_node  *value      = get_compound_ent_value(ent, i);
1212                 int      value_len   = get_mode_size_bits(get_irn_mode(value));
1213
1214                 assert(offset_bits >= 0);
1215
1216                 if (offset_bits != 0 ||
1217                                 (value_len != 8 && value_len != 16 && value_len != 32 && value_len != 64)) {
1218                         tarval *tv = get_atomic_init_tv(value);
1219                         unsigned char curr_bits, last_bits = 0;
1220                         if (tv == NULL) {
1221                                 panic("Couldn't get numeric value for bitfield initializer '%s'",
1222                                                 get_entity_ld_name(ent));
1223                         }
1224                         /* normalize offset */
1225                         offset += offset_bits >> 3;
1226                         offset_bits &= 7;
1227
1228                         for (j = 0; value_len + offset_bits > 0; ++j) {
1229                                 assert(offset + j < last_ofs);
1230                                 assert(vals[offset + j].kind == BITFIELD || vals[offset + j].v.value == NULL);
1231                                 vals[offset + j].kind = BITFIELD;
1232                                 curr_bits = get_tarval_sub_bits(tv, j);
1233                                 vals[offset + j].v.bf_val |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
1234                                 value_len -= 8;
1235                                 last_bits = curr_bits;
1236                         }
1237                 } else {
1238                         int i;
1239
1240                         assert(offset < last_ofs);
1241                         assert(vals[offset].kind == NORMAL);
1242                         for (i = 1; i < value_len / 8; ++i) {
1243                                 assert(vals[offset + i].v.value == NULL);
1244                         }
1245                         vals[offset].v.value = value;
1246                 }
1247         }
1248
1249         /* now write them sorted */
1250         for (k = 0; k < last_ofs; ) {
1251                 int space = 0, skip = 0;
1252                 if (vals[k].kind == NORMAL) {
1253                         if (vals[k].v.value != NULL) {
1254                                 emit_atomic_init(env, vals[k].v.value);
1255                                 skip = get_mode_size_bytes(get_irn_mode(vals[k].v.value)) - 1;
1256                         } else {
1257                                 space = 1;
1258                         }
1259                 } else {
1260                         assert(vals[k].kind == BITFIELD);
1261                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
1262                 }
1263
1264                 ++k;
1265                 while (k < last_ofs && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
1266                         ++space;
1267                         ++k;
1268                 }
1269                 space -= skip;
1270                 assert(space >= 0);
1271
1272                 /* a gap */
1273                 if (space > 0) {
1274                         be_emit_irprintf("\t.space\t%d\n", space);
1275                         be_emit_write_line();
1276                 }
1277         }
1278         xfree(vals);
1279 }
1280
1281 static void emit_align(unsigned p2alignment)
1282 {
1283         be_emit_irprintf("\t.p2align\t%u\n", log2_floor(p2alignment));
1284         be_emit_write_line();
1285 }
1286
1287 static unsigned get_effective_entity_alignment(const ir_entity *entity)
1288 {
1289         unsigned alignment = get_entity_alignment(entity);
1290         if (alignment == 0) {
1291                 ir_type *type = get_entity_type(entity);
1292                 alignment     = get_type_alignment_bytes(type);
1293         }
1294         return alignment;
1295 }
1296
1297 static void emit_common(const ir_entity *entity)
1298 {
1299         unsigned size      = get_type_size_bytes(get_entity_type(entity));
1300         unsigned alignment = get_effective_entity_alignment(entity);
1301
1302         if (get_entity_linkage(entity) & IR_LINKAGE_WEAK) {
1303                 emit_weak(entity);
1304         }
1305
1306         switch (be_gas_object_file_format) {
1307         case OBJECT_FILE_FORMAT_MACH_O:
1308                 be_emit_cstring("\t.comm ");
1309                 be_gas_emit_entity(entity);
1310                 be_emit_irprintf(",%u,%u\n", size, log2_floor(alignment));
1311                 be_emit_write_line();
1312                 return;
1313         case OBJECT_FILE_FORMAT_ELF:
1314                 be_emit_cstring("\t.comm ");
1315                 be_gas_emit_entity(entity);
1316                 be_emit_irprintf(",%u,%u\n", size, alignment);
1317                 be_emit_write_line();
1318                 return;
1319         case OBJECT_FILE_FORMAT_COFF:
1320                 be_emit_cstring("\t.comm ");
1321                 be_gas_emit_entity(entity);
1322                 be_emit_irprintf(",%u # %u\n", size, alignment);
1323                 be_emit_write_line();
1324                 return;
1325         }
1326         panic("invalid object file format");
1327 }
1328
1329 static void emit_local_common(const ir_entity *entity)
1330 {
1331         unsigned size      = get_type_size_bytes(get_entity_type(entity));
1332         unsigned alignment = get_effective_entity_alignment(entity);
1333
1334         if (get_entity_linkage(entity) & IR_LINKAGE_WEAK) {
1335                 emit_weak(entity);
1336         }
1337
1338         switch (be_gas_object_file_format) {
1339         case OBJECT_FILE_FORMAT_MACH_O:
1340                 be_emit_cstring("\t.lcomm ");
1341                 be_gas_emit_entity(entity);
1342                 be_emit_irprintf(",%u,%u\n", size, log2_floor(alignment));
1343                 be_emit_write_line();
1344                 return;
1345         case OBJECT_FILE_FORMAT_ELF:
1346                 be_emit_cstring("\t.local ");
1347                 be_gas_emit_entity(entity);
1348                 be_emit_cstring("\n");
1349                 be_emit_write_line();
1350                 be_emit_cstring("\t.comm ");
1351                 be_gas_emit_entity(entity);
1352                 be_emit_irprintf(",%u,%u\n", size, alignment);
1353                 be_emit_write_line();
1354                 return;
1355         case OBJECT_FILE_FORMAT_COFF:
1356                 be_emit_cstring("\t.lcomm ");
1357                 be_gas_emit_entity(entity);
1358                 be_emit_irprintf(",%u # %u\n", size, alignment);
1359                 be_emit_write_line();
1360                 return;
1361         }
1362         panic("invalid object file format");
1363 }
1364
1365 static void emit_indirect_symbol(const ir_entity *entity, be_gas_section_t section)
1366 {
1367         /* we can only do PIC code on macho so far */
1368         assert(be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O);
1369
1370         be_gas_emit_entity(entity);
1371         be_emit_cstring(":\n");
1372         be_emit_write_line();
1373         be_emit_cstring("\t.indirect_symbol ");
1374         be_emit_ident(get_entity_ident(entity));
1375         be_emit_char('\n');
1376         be_emit_write_line();
1377         if (section == GAS_SECTION_PIC_TRAMPOLINES) {
1378                 be_emit_cstring("\thlt ; hlt ; hlt ; hlt ; hlt\n");
1379                 be_emit_write_line();
1380         } else {
1381                 assert(section == GAS_SECTION_PIC_SYMBOLS);
1382                 be_emit_cstring("\t.long 0\n");
1383                 be_emit_write_line();
1384         }
1385 }
1386
1387 char const *be_gas_get_private_prefix(void)
1388 {
1389         return
1390                 be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O ? "L" :
1391                 ".L";
1392 }
1393
1394 void be_gas_emit_entity(const ir_entity *entity)
1395 {
1396         if (entity->type == firm_code_type) {
1397                 ir_label_t label = get_entity_label(entity);
1398                 be_emit_irprintf("%s_%lu", be_gas_get_private_prefix(), label);
1399                 return;
1400         }
1401
1402         if (get_entity_visibility(entity) == ir_visibility_private) {
1403                 be_emit_string(be_gas_get_private_prefix());
1404         }
1405         be_emit_ident(get_entity_ld_ident(entity));
1406 }
1407
1408 void be_gas_emit_block_name(const ir_node *block)
1409 {
1410         if (has_Block_entity(block)) {
1411                 ir_entity *entity = get_Block_entity(block);
1412                 be_gas_emit_entity(entity);
1413         } else {
1414                 be_emit_irprintf("%s%ld", be_gas_get_private_prefix(), get_irn_node_nr(block));
1415         }
1416 }
1417
1418 /**
1419  * Dump a global entity.
1420  *
1421  * @param env  the gas output environment
1422  * @param ent  the entity to be dumped
1423  */
1424 static void emit_global(be_gas_decl_env_t *env, const ir_entity *entity)
1425 {
1426         ir_type          *type       = get_entity_type(entity);
1427         ident            *ld_ident   = get_entity_ld_ident(entity);
1428         unsigned          alignment  = get_effective_entity_alignment(entity);
1429         be_gas_section_t  section    = determine_section(env, entity);
1430         ir_visibility     visibility = get_entity_visibility(entity);
1431         ir_linkage        linkage    = get_entity_linkage(entity);
1432
1433         /* block labels are already emittet in the code */
1434         if (type == firm_code_type)
1435                 return;
1436
1437         /* we already emitted all methods. Except for the trampolines which
1438          * the assembler/linker generates */
1439         if (is_Method_type(type) && section != GAS_SECTION_PIC_TRAMPOLINES) {
1440                 /* functions with graph are already emitted with
1441                  * be_gas_emit_function_prolog */
1442                 if (get_entity_irg(entity) == NULL) {
1443                         emit_visibility(entity);
1444                 }
1445                 return;
1446         }
1447
1448         be_dbg_variable(entity);
1449
1450         if (section == GAS_SECTION_BSS) {
1451                 ir_visibility visibility = get_entity_visibility(entity);
1452
1453                 switch (visibility) {
1454                 case ir_visibility_local:
1455                 case ir_visibility_private:
1456                         emit_local_common(entity);
1457                         return;
1458                 case ir_visibility_default:
1459                         if (linkage & IR_LINKAGE_MERGE) {
1460                                 emit_common(entity);
1461                                 return;
1462                         }
1463                         break;
1464                 case ir_visibility_external:
1465                         if (linkage & IR_LINKAGE_MERGE)
1466                                 panic("merge link semantic not supported for extern entities");
1467                         break;
1468                 }
1469         }
1470
1471         emit_visibility(entity);
1472         if (visibility == ir_visibility_external) {
1473                 /* nothing to do for externally defined values */
1474                 return;
1475         }
1476
1477         if (!is_po2(alignment))
1478                 panic("alignment not a power of 2");
1479
1480         emit_section(section, entity);
1481
1482         if (section == GAS_SECTION_PIC_TRAMPOLINES
1483                         || section == GAS_SECTION_PIC_SYMBOLS) {
1484                 emit_indirect_symbol(entity, section);
1485                 return;
1486         }
1487
1488         /* alignment */
1489         if (alignment > 1) {
1490                 emit_align(alignment);
1491         }
1492         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_ELF
1493                         && be_gas_emit_types) {
1494                 be_emit_cstring("\t.type\t");
1495                 be_gas_emit_entity(entity);
1496                 be_emit_cstring(", ");
1497                 be_emit_char(be_gas_elf_type_char);
1498                 be_emit_cstring("object\n\t.size\t");\
1499                 be_gas_emit_entity(entity);
1500                 be_emit_irprintf(", %u\n", get_type_size_bytes(type));
1501         }
1502
1503         if (get_id_str(ld_ident)[0] != '\0') {
1504             be_gas_emit_entity(entity);
1505                 be_emit_cstring(":\n");
1506                 be_emit_write_line();
1507         }
1508
1509         if (entity_is_null(entity)) {
1510                 be_emit_irprintf("\t.space %u\n", get_type_size_bytes(type));
1511                 be_emit_write_line();
1512         } else if (entity_has_compound_ent_values(entity)) {
1513                 emit_compound_graph_init(env, entity);
1514         } else {
1515                 assert(entity->initializer != NULL);
1516                 emit_initializer(env, entity);
1517         }
1518 }
1519
1520 /**
1521  * Dumps declarations of global variables and the initialization code.
1522  *
1523  * @param gt                a global like type, either the global or the TLS one
1524  * @param env               an environment
1525  */
1526 static void be_gas_emit_globals(ir_type *gt, be_gas_decl_env_t *env)
1527 {
1528         int i, n = get_compound_n_members(gt);
1529
1530         for (i = 0; i < n; i++) {
1531                 ir_entity *ent = get_compound_member(gt, i);
1532                 emit_global(env, ent);
1533         }
1534 }
1535
1536 /************************************************************************/
1537
1538 /* Generate all entities. */
1539 void be_gas_emit_decls(const be_main_env_t *main_env)
1540 {
1541         be_gas_decl_env_t env;
1542         memset(&env, 0, sizeof(env));
1543
1544         /* dump global type */
1545         env.main_env = main_env;
1546         env.section  = (be_gas_section_t) -1;
1547
1548         be_gas_emit_globals(get_glob_type(), &env);
1549         be_gas_emit_globals(get_tls_type(), &env);
1550         be_gas_emit_globals(get_segment_type(IR_SEGMENT_CONSTRUCTORS), &env);
1551         be_gas_emit_globals(get_segment_type(IR_SEGMENT_DESTRUCTORS), &env);
1552         be_gas_emit_globals(main_env->pic_symbols_type, &env);
1553         be_gas_emit_globals(main_env->pic_trampolines_type, &env);
1554
1555         /**
1556          * ".subsections_via_symbols marks object files which are OK to divide
1557          * their section contents into individual blocks".
1558          * From my understanding this means no label points in the middle of an
1559          * object which we want to address as a whole. Firm code should be fine
1560          * with this.
1561          */
1562         if (be_gas_object_file_format == OBJECT_FILE_FORMAT_MACH_O) {
1563                 be_emit_cstring("\t.subsections_via_symbols\n");
1564                 be_emit_write_line();
1565         }
1566 }