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

   1 /*
   2  * Copyright (C) 1995-2007 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 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include "begnuas.h"
  32
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <ctype.h>
  36 #include <assert.h>
  37
  38 #include "obst.h"
  39 #include "tv.h"
  40 #include "irnode.h"
  41 #include "irprog.h"
  42 #include "pdeq.h"
  43 #include "error.h"
  44
  45 #include "be_t.h"
  46 #include "beemitter.h"
  47 #include "be_dbgout.h"
  48
  49 typedef struct obstack obstack_t;
  50
  51 /** by default, we generate assembler code for the Linux gas */
  52 be_gas_flavour_t be_gas_flavour = GAS_FLAVOUR_NORMAL;
  53
  54 /**
  55  * Return the pseudo-instruction to be issued for a section switch
  56  * depending on the current flavour.
  57  *
  58  * @param section  the section to switch to
  59  *
  60  * @return  the pseudo-instruction
  61  */
  62 static const char *get_section_name(be_gas_section_t section) {
  63         static const char *text[GAS_FLAVOUR_MAX][GAS_SECTION_MAX] = {
  64                 {
  65                         ".section\t.text",
  66                         ".section\t.data",
  67                         ".section\t.rodata",
  68                         ".section\t.bss",
  69                         ".section\t.tbss,\"awT\",@nobits",
  70                         ".section\t.ctors,\"aw\",@progbits"
  71                 },
  72                 {
  73                         ".section\t.text",
  74                         ".section\t.data",
  75                         ".section .rdata,\"dr\"",
  76                         ".section\t.bss",
  77                         ".section\t.tbss,\"awT\",@nobits",
  78                         ".section\t.ctors,\"aw\",@progbits"
  79                 }
  80         };
  81
  82         assert((int) be_gas_flavour >= 0 && be_gas_flavour < GAS_FLAVOUR_MAX);
  83         assert((int) section >= 0 && section < GAS_SECTION_MAX);
  84         return text[be_gas_flavour][section];
  85 }
  86
  87 /**
  88  * Emit necessary code to switch to a section.
  89  *
  90  * @param env      the emitter environment
  91  * @param section  the section to switch to
  92  */
  93 void be_gas_emit_switch_section(be_emit_env_t *env, be_gas_section_t section) {
  94         be_emit_char(env, '\t');
  95         be_emit_string(env, get_section_name(section));
  96         be_emit_char(env, '\n');
  97         be_emit_write_line(env);
  98 }
  99
 100 /**
 101  * An environment containing all needed dumper data.
 102  * Currently we create the file completely in memory first, then
 103  * write it to the disk. This is an artifact from the old C-generating backend
 104  * and even there NOT needed. So we might change it in the future.
 105  */
 106 typedef struct _be_gas_decl_env {
 107         obstack_t *rodata_obst;        /**< An obstack that will be filled with all rodata entities. */
 108         obstack_t *data_obst;          /**< An obstack that will be filled with the initialized entities. */
 109         obstack_t *bss_obst;           /**< An obstack that will be filled with the uninitialized entities. */
 110         obstack_t *ctor_obst;          /**< An obstack that will be filled with the constructor entities. */
 111         const be_main_env_t *main_env; /**< The main backend environment, used for it's debug handle. */
 112         waitq     *worklist;           /**< A worklist we use to place not yet handled entities on. */
 113 } be_gas_decl_env_t;
 114
 115 /************************************************************************/
 116
 117 /**
 118  * Output a tarval.
 119  *
 120  * @param obst   the obstack where the data is written too
 121  * @param tv     the tarval
 122  * @param bytes  the width of the tarvals value in bytes
 123  */
 124 static void dump_arith_tarval(obstack_t *obst, tarval *tv, int bytes)
 125 {
 126         switch (bytes) {
 127
 128         case 1:
 129                 obstack_printf(obst, "0x%02x", get_tarval_sub_bits(tv, 0));
 130                 break;
 131
 132         case 2:
 133                 obstack_printf(obst, "0x%02x%02x", get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 134                 break;
 135
 136         case 4:
 137                 obstack_printf(obst, "0x%02x%02x%02x%02x",
 138                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 139                 break;
 140
 141         case 8:
 142                 obstack_printf(obst, "0x%02x%02x%02x%02x%02x%02x%02x%02x",
 143                         get_tarval_sub_bits(tv, 7), get_tarval_sub_bits(tv, 6), get_tarval_sub_bits(tv, 5), get_tarval_sub_bits(tv, 4),
 144                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 145                 break;
 146
 147         case 10:
 148         case 12:
 149                 break;
 150
 151         case 16:
 152                 obstack_printf(obst, "0x%02x%02x%02x%02x%02x%02x%02x%02x"
 153                                                "%02x%02x%02x%02x%02x%02x%02x%02x",
 154                         get_tarval_sub_bits(tv, 15), get_tarval_sub_bits(tv, 16),
 155                         get_tarval_sub_bits(tv, 13), get_tarval_sub_bits(tv, 12),
 156                         get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
 157                         get_tarval_sub_bits(tv, 9), get_tarval_sub_bits(tv, 8),
 158                         get_tarval_sub_bits(tv, 7), get_tarval_sub_bits(tv, 6),
 159                         get_tarval_sub_bits(tv, 5), get_tarval_sub_bits(tv, 4),
 160                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2),
 161                         get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 162                 break;
 163
 164
 165         default:
 166                 fprintf(stderr, "Try to dump an tarval with %d bytes\n", bytes);
 167                 assert(0);
 168         }
 169 }
 170
 171 /**
 172  * Return the label prefix for labeled blocks.
 173  */
 174 const char *be_gas_label_prefix(void) {
 175         return ".LG";
 176 }
 177
 178 /**
 179  * Dump a label.
 180  */
 181 static void dump_label(obstack_t *obst, ir_label_t label) {
 182         obstack_printf(obst, "%s%ld", be_gas_label_prefix(), label);
 183 }
 184
 185 /**
 186  * Return the tarval of an atomic initializer.
 187  *
 188  * @param init  a node representing the initializer (on the const code irg)
 189  *
 190  * @return the tarval
 191  */
 192 static tarval *get_atomic_init_tv(ir_node *init)
 193 {
 194         for (;;) {
 195                 ir_mode *mode = get_irn_mode(init);
 196
 197                 switch (get_irn_opcode(init)) {
 198
 199                 case iro_Cast:
 200                         init = get_Cast_op(init);
 201                         continue;
 202
 203                 case iro_Conv:
 204                         init = get_Conv_op(init);
 205                         continue;
 206
 207                 case iro_Const:
 208                         return get_Const_tarval(init);
 209
 210                 case iro_SymConst:
 211                         switch (get_SymConst_kind(init)) {
 212                         case symconst_type_size:
 213                                 return new_tarval_from_long(get_type_size_bytes(get_SymConst_type(init)), mode);
 214
 215                         case symconst_type_align:
 216                                 return new_tarval_from_long(get_type_alignment_bytes(get_SymConst_type(init)), mode);
 217
 218                         case symconst_ofs_ent:
 219                                 return new_tarval_from_long(get_entity_offset(get_SymConst_entity(init)), mode);
 220
 221                         case symconst_enum_const:
 222                                 return get_enumeration_value(get_SymConst_enum(init));
 223
 224                         case symconst_label:
 225                                 return NULL;
 226
 227                         default:
 228                                 return NULL;
 229                         }
 230
 231                 default:
 232                         return NULL;
 233                 }
 234         }
 235 }
 236
 237 /**
 238  * Dump an atomic value.
 239  *
 240  * @param env   the gas output environment
 241  * @param obst  an obstack the output is written to
 242  * @param init  a node representing the atomic value (on the const code irg)
 243  */
 244 static void do_dump_atomic_init(be_gas_decl_env_t *env, obstack_t *obst,
 245                                 ir_node *init)
 246 {
 247         ir_mode *mode = get_irn_mode(init);
 248         int bytes     = get_mode_size_bytes(mode);
 249         tarval *tv;
 250         ir_label_t label;
 251         ir_entity *ent;
 252
 253         switch (get_irn_opcode(init)) {
 254
 255         case iro_Cast:
 256                 do_dump_atomic_init(env, obst, get_Cast_op(init));
 257                 return;
 258
 259         case iro_Conv:
 260                 do_dump_atomic_init(env, obst, get_Conv_op(init));
 261                 return;
 262
 263         case iro_Const:
 264                 tv = get_Const_tarval(init);
 265
 266                 /* it's a arithmetic value */
 267                 dump_arith_tarval(obst, tv, bytes);
 268                 return;
 269
 270         case iro_SymConst:
 271                 switch (get_SymConst_kind(init)) {
 272                 case symconst_addr_name:
 273                         obstack_printf(obst, "%s", get_id_str(get_SymConst_name(init)));
 274                         break;
 275
 276                 case symconst_addr_ent:
 277                         ent = get_SymConst_entity(init);
 278                         if(!is_entity_backend_marked(ent)) {
 279                                 waitq_put(env->worklist, ent);
 280                                 set_entity_backend_marked(ent, 1);
 281                         }
 282                         obstack_printf(obst, "%s", get_entity_ld_name(ent));
 283                         break;
 284
 285                 case symconst_ofs_ent:
 286                         ent = get_SymConst_entity(init);
 287 #if 0       /* not needed, is it? */
 288                         if(!is_entity_backend_marked(ent)) {
 289                                 waitq_put(env->worklist, ent);
 290                                 set_entity_backend_marked(ent, 1);
 291                         }
 292 #endif
 293                         obstack_printf(obst, "%d", get_entity_offset(ent));
 294                         break;
 295
 296                 case symconst_type_size:
 297                         obstack_printf(obst, "%d", get_type_size_bytes(get_SymConst_type(init)));
 298                         break;
 299
 300                 case symconst_type_align:
 301                         obstack_printf(obst, "%d", get_type_alignment_bytes(get_SymConst_type(init)));
 302                         break;
 303
 304                 case symconst_enum_const:
 305                         tv = get_enumeration_value(get_SymConst_enum(init));
 306                         dump_arith_tarval(obst, tv, bytes);
 307                         break;
 308
 309                 case symconst_label:
 310                         label = get_SymConst_label(init);
 311                         dump_label(obst, label);
 312                         break;
 313
 314                 default:
 315                         assert(!"dump_atomic_init(): don't know how to init from this SymConst");
 316                 }
 317                 return;
 318
 319                 case iro_Add:
 320                         do_dump_atomic_init(env, obst, get_Add_left(init));
 321                         obstack_printf(obst, " + ");
 322                         do_dump_atomic_init(env, obst, get_Add_right(init));
 323                         return;
 324
 325                 case iro_Sub:
 326                         do_dump_atomic_init(env, obst, get_Sub_left(init));
 327                         obstack_printf(obst, " - ");
 328                         do_dump_atomic_init(env, obst, get_Sub_right(init));
 329                         return;
 330
 331                 case iro_Mul:
 332                         do_dump_atomic_init(env, obst, get_Mul_left(init));
 333                         obstack_printf(obst, " * ");
 334                         do_dump_atomic_init(env, obst, get_Mul_right(init));
 335                         return;
 336
 337                 default:
 338                         assert(0 && "dump_atomic_init(): unknown IR-node");
 339         }
 340 }
 341
 342 /**
 343  * Dumps the type for given size (.byte, .long, ...)
 344  *
 345  * @param obst  an obstack the output is written to
 346  * @param size  the size in bytes
 347  */
 348 static void dump_size_type(obstack_t *obst, int size) {
 349         switch (size) {
 350
 351         case 1:
 352                 obstack_printf(obst, "\t.byte\t");
 353                 break;
 354
 355         case 2:
 356                 obstack_printf(obst, "\t.value\t");
 357                 break;
 358
 359         case 4:
 360                 obstack_printf(obst, "\t.long\t");
 361                 break;
 362
 363         case 8:
 364                 obstack_printf(obst, "\t.quad\t");
 365                 break;
 366
 367         case 10:
 368         case 12:
 369                 /* handled in arith */
 370                 break;
 371
 372         case 16:
 373                 obstack_printf(obst, "\t.octa\t");
 374                 break;
 375
 376         default:
 377                 fprintf(stderr, "Try to dump a type with %d bytes\n", size);
 378                 assert(0);
 379         }
 380 }
 381
 382 /**
 383  * Dump an atomic value to an obstack.
 384  *
 385  * @param env   the gas output environment
 386  * @param obst  an obstack the output is written to
 387  * @param init  a node representing the atomic value (on the const code irg)
 388  */
 389 static void dump_atomic_init(be_gas_decl_env_t *env, obstack_t *obst,
 390                              ir_node *init)
 391 {
 392         ir_mode *mode = get_irn_mode(init);
 393         int bytes     = get_mode_size_bytes(mode);
 394
 395         dump_size_type(obst, bytes);
 396         do_dump_atomic_init(env, obst, init);
 397         obstack_printf(obst, "\n");
 398 }
 399
 400 /************************************************************************/
 401 /* Routines to dump global variables                                    */
 402 /************************************************************************/
 403
 404 /**
 405  * Determine if an entity is a string constant
 406  * @param ent The entity
 407  * @return 1 if it is a string constant, 0 otherwise
 408  */
 409 static int ent_is_string_const(ir_entity *ent)
 410 {
 411         ir_type *type, *element_type;
 412         ir_mode *mode;
 413         int i, c, n;
 414
 415         type = get_entity_type(ent);
 416
 417         /* if it's an array */
 418         if (!is_Array_type(type))
 419                 return 0;
 420
 421         element_type = get_array_element_type(type);
 422
 423         /* and the array's element type is primitive */
 424         if (!is_Primitive_type(element_type))
 425                 return 0;
 426
 427         /* and the mode of the element type is an int of
 428          * the same size as the byte mode */
 429         mode = get_type_mode(element_type);
 430         if (!mode_is_int(mode)
 431                 || get_mode_size_bits(mode) != get_mode_size_bits(mode_Bs))
 432                 return 0;
 433
 434         /* if it contains only printable chars and a 0 at the end */
 435         n = get_compound_ent_n_values(ent);
 436         for (i = 0; i < n; ++i) {
 437                 ir_node *irn = get_compound_ent_value(ent, i);
 438                 if(get_irn_opcode(irn) != iro_Const)
 439                         return 0;
 440
 441                 c = (int) get_tarval_long(get_Const_tarval(irn));
 442
 443                 if((i < n - 1 && !(isgraph(c) || isspace(c)))
 444                                 || (i == n - 1 && c != '\0'))
 445                         return 0;
 446         }
 447
 448         /* then we can emit it as a string constant */
 449         return 1;
 450 }
 451
 452 /**
 453  * Dump a string constant.
 454  * No checks are made!!
 455  *
 456  * @param obst The obst to dump on.
 457  * @param ent  The entity to dump.
 458  */
 459 static void dump_string_cst(obstack_t *obst, ir_entity *ent)
 460 {
 461         int      i, n;
 462         ir_type *type;
 463         int      type_size;
 464         int      remaining_space;
 465
 466         obstack_printf(obst, "\t.string \"");
 467         n = get_compound_ent_n_values(ent);
 468
 469         for (i = 0; i < n-1; ++i) {
 470                 ir_node *irn;
 471                 int c;
 472
 473                 irn = get_compound_ent_value(ent, i);
 474                 c = (int) get_tarval_long(get_Const_tarval(irn));
 475
 476                 switch (c) {
 477                 case '"' : obstack_printf(obst, "\\\""); break;
 478                 case '\n': obstack_printf(obst, "\\n"); break;
 479                 case '\r': obstack_printf(obst, "\\r"); break;
 480                 case '\t': obstack_printf(obst, "\\t"); break;
 481                 case '\\': obstack_printf(obst, "\\\\"); break;
 482                 default  :
 483                         if (isprint(c))
 484                                 obstack_printf(obst, "%c", c);
 485                         else
 486                                 obstack_printf(obst, "\\%o", c);
 487                         break;
 488                 }
 489         }
 490         obstack_printf(obst, "\"\n");
 491
 492         type            = get_entity_type(ent);
 493         type_size       = get_type_size_bytes(type);
 494         remaining_space = type_size - n;
 495         assert(remaining_space >= 0);
 496         if(remaining_space > 0) {
 497                 obstack_printf(obst, "\t.skip\t%d\n", remaining_space);
 498         }
 499 }
 500
 501 enum normal_or_bitfield_kind {
 502         NORMAL = 0,
 503         BITFIELD
 504 };
 505
 506 typedef struct {
 507         enum normal_or_bitfield_kind kind;
 508         union {
 509                 ir_node *value;
 510                 unsigned char bf_val;
 511         } v;
 512 } normal_or_bitfield;
 513
 514 /**
 515  * Dump an initializer for a compound entity.
 516  */
 517 static void dump_compound_init(be_gas_decl_env_t *env, obstack_t *obst,
 518                                ir_entity *ent)
 519 {
 520         normal_or_bitfield *vals;
 521         int i, j, n = get_compound_ent_n_values(ent);
 522         int last_ofs;
 523
 524         /* Find the initializer size. Sorrily gcc support a nasty feature:
 525            The last field of a compound may be a flexible array. This allows
 526            initializers bigger than the type size. */
 527         last_ofs = get_type_size_bytes(get_entity_type(ent));
 528         for (i = 0; i < n; ++i) {
 529                 int offset = get_compound_ent_value_offset_bytes(ent, i);
 530                 int bits_remainder = get_compound_ent_value_offset_bit_remainder(ent, i);
 531                 const compound_graph_path *path = get_compound_ent_value_path(ent, i);
 532                 int path_len = get_compound_graph_path_length(path);
 533                 ir_entity *last_ent = get_compound_graph_path_node(path, path_len - 1);
 534                 int value_len = get_type_size_bits(get_entity_type(last_ent));
 535
 536                 offset += (value_len + bits_remainder + 7) >> 3;
 537
 538                 if (offset > last_ofs) {
 539                         last_ofs = offset;
 540                 }
 541         }
 542
 543         /*
 544          * In the worst case, every initializer allocates one byte.
 545          * Moreover, initializer might be big, do not allocate on stack.
 546          */
 547         vals = xcalloc(last_ofs, sizeof(vals[0]));
 548
 549         /* collect the values and store them at the offsets */
 550         for (i = 0; i < n; ++i) {
 551                 const compound_graph_path *path = get_compound_ent_value_path(ent, i);
 552                 int path_len = get_compound_graph_path_length(path);
 553                 int offset = get_compound_ent_value_offset_bytes(ent, i);
 554                 int offset_bits = get_compound_ent_value_offset_bit_remainder(ent, i);
 555                 ir_node *value = get_compound_ent_value(ent, i);
 556                 ir_entity *last_ent = get_compound_graph_path_node(path, path_len - 1);
 557                 int value_len = get_type_size_bits(get_entity_type(last_ent));
 558                 assert(offset >= 0);
 559                 assert(offset_bits >= 0);
 560
 561                 if (offset_bits != 0 ||
 562                         (value_len != 8 && value_len != 16 && value_len != 32 && value_len != 64)) {
 563                         tarval *shift, *shifted;
 564                         tarval *tv = get_atomic_init_tv(value);
 565                         if (tv == NULL) {
 566                                 panic("Couldn't get numeric value for bitfield initializer '%s'\n",
 567                                       get_entity_ld_name(ent));
 568                         }
 569                         tv = tarval_convert_to(tv, mode_Lu);
 570                         shift = new_tarval_from_long(offset_bits, mode_Is);
 571                         shifted = tarval_shl(tv, shift);
 572                         if (shifted == tarval_bad || shifted == tarval_undefined) {
 573                                 panic("Couldn't shift numeric value for bitfield initializer '%s'\n",
 574                                       get_entity_ld_name(ent));
 575                         }
 576
 577                         for (j = 0; value_len > 0; ++j) {
 578                                 assert(offset + j < last_ofs);
 579                                 assert(vals[offset + j].kind == BITFIELD || vals[offset + j].v.value == NULL);
 580                                 vals[offset + j].kind = BITFIELD;
 581                                 vals[offset + j].v.bf_val |= get_tarval_sub_bits(shifted, j);
 582                                 value_len -= 8 - offset_bits;
 583                                 offset_bits = 0;
 584                         }
 585                 } else {
 586                         assert(offset < last_ofs);
 587                         assert(vals[offset].kind == NORMAL);
 588                         assert(vals[offset].v.value == NULL);
 589                         vals[offset].v.value = value;
 590                 }
 591         }
 592
 593         /* now write them sorted */
 594         for (i = 0; i < last_ofs; ) {
 595                 int space = 0, skip = 0;
 596                 if (vals[i].kind == NORMAL) {
 597                         if(vals[i].v.value != NULL) {
 598                                 dump_atomic_init(env, obst, vals[i].v.value);
 599                                 skip = get_mode_size_bytes(get_irn_mode(vals[i].v.value)) - 1;
 600                         } else {
 601                                 space = 1;
 602                         }
 603                 } else {
 604                         assert(vals[i].kind == BITFIELD);
 605                         obstack_printf(obst, "\t.byte\t%d\n", vals[i].v.bf_val);
 606                 }
 607
 608                 ++i;
 609                 while (i < last_ofs && vals[i].kind == NORMAL && vals[i].v.value == NULL) {
 610                         ++space;
 611                         ++i;
 612                 }
 613                 space -= skip;
 614                 assert(space >= 0);
 615
 616                 /* a gap */
 617                 if (space > 0)
 618                         obstack_printf(obst, "\t.skip\t%d\n", space);
 619         }
 620         xfree(vals);
 621 }
 622
 623 /**
 624  * Dump a global entity.
 625  *
 626  * @param env           the gas output environment
 627  * @param ent           the entity to be dumped
 628  * @param emit_commons  if non-zero, emit commons (non-local uninitialized entities)
 629  */
 630 static void dump_global(be_gas_decl_env_t *env, ir_entity *ent, int emit_commons)
 631 {
 632         obstack_t *obst;
 633         ir_type *type = get_entity_type(ent);
 634         const char *ld_name = get_entity_ld_name(ent);
 635         int align = get_type_alignment_bytes(type);
 636         int emit_as_common = 0;
 637         ir_variability variability;
 638         ir_visibility visibility;
 639
 640         obst = env->data_obst;
 641         if (is_Method_type(type)) {
 642                 if (get_method_img_section(ent) == section_constructors) {
 643                         obst = env->ctor_obst;
 644                         obstack_printf(obst, ".balign\t%d\n", align);
 645                         dump_size_type(obst, align);
 646                         obstack_printf(obst, "%s\n", ld_name);
 647                 }
 648                 return;
 649         }
 650
 651         variability = get_entity_variability(ent);
 652         visibility = get_entity_visibility(ent);
 653         if (variability == variability_constant) {
 654                 /* a constant entity, put it on the rdata */
 655                 obst = env->rodata_obst;
 656         } else if (variability == variability_uninitialized) {
 657                 /* uninitialized entity put it in bss segment */
 658                 obst = env->bss_obst;
 659                 if (emit_commons && visibility != visibility_local)
 660                         emit_as_common = 1;
 661         }
 662
 663         be_dbg_variable(env->main_env->db_handle, obst, ent);
 664
 665         /* global or not global */
 666         if (visibility == visibility_external_visible && !emit_as_common) {
 667                 obstack_printf(obst, ".global\t%s\n", ld_name);
 668         } else if(visibility == visibility_external_allocated) {
 669                 obstack_printf(obst, ".global\t%s\n", ld_name);
 670                 /* we can return now... */
 671                 return;
 672         }
 673         /* alignment */
 674         if (align > 1 && !emit_as_common) {
 675                 obstack_printf(obst, ".balign\t%d\n", align);
 676         }
 677
 678         if (!emit_as_common) {
 679                 obstack_printf(obst, "%s:\n", ld_name);
 680         }
 681
 682         if (variability == variability_uninitialized) {
 683                 if(emit_as_common) {
 684                         if (be_gas_flavour == GAS_FLAVOUR_NORMAL)
 685                                 obstack_printf(obst, "\t.comm %s,%d,%d\n",
 686                                         ld_name, get_type_size_bytes(type), align);
 687                         else
 688                                 obstack_printf(obst, "\t.comm %s,%d # %d\n",
 689                                         ld_name, get_type_size_bytes(type), align);
 690                 } else {
 691                         obstack_printf(obst, "\t.zero %d\n", get_type_size_bytes(type));
 692                 }
 693         } else {
 694                 if (is_atomic_entity(ent)) {
 695                         dump_atomic_init(env, obst, get_atomic_ent_value(ent));
 696                 } else {
 697                         /* sort_compound_ent_values(ent); */
 698
 699                         switch (get_type_tpop_code(get_entity_type(ent))) {
 700                         case tpo_array:
 701                                 if (ent_is_string_const(ent))
 702                                         dump_string_cst(obst, ent);
 703                                 else
 704                                         dump_compound_init(env, obst, ent);
 705                                 break;
 706                         case tpo_struct:
 707                         case tpo_class:
 708                         case tpo_union:
 709                                 dump_compound_init(env, obst, ent);
 710                                 break;
 711                         default:
 712                                 assert(0);
 713                         }
 714                 }
 715         }
 716 }
 717
 718 /**
 719  * Dumps declarations of global variables and the initialization code.
 720  *
 721  * @param gt                a global like type, either the global or the TLS one
 722  * @param env               an environment
 723  * @param emit_commons      if non-zero, emit commons (non-local uninitialized entities)
 724  * @param only_emit_marked  if non-zero, external allocated entities that do not have
 725  *                          its visited flag set are ignored
 726  */
 727 static void be_gas_dump_globals(ir_type *gt, be_gas_decl_env_t *env,
 728                               int emit_commons, int only_emit_marked)
 729 {
 730         int i, n = get_compound_n_members(gt);
 731         waitq *worklist = new_waitq();
 732
 733         if (only_emit_marked) {
 734                 for (i = 0; i < n; i++) {
 735                         ir_entity *ent = get_compound_member(gt, i);
 736                         if (is_entity_backend_marked(ent) ||
 737                             get_entity_visibility(ent) != visibility_external_allocated) {
 738                                 waitq_put(worklist, ent);
 739                                 set_entity_backend_marked(ent, 1);
 740                         }
 741                 }
 742         } else {
 743                 for (i = 0; i < n; i++) {
 744                         ir_entity *ent = get_compound_member(gt, i);
 745                         set_entity_backend_marked(ent, 1);
 746                         waitq_put(worklist, ent);
 747                 }
 748         }
 749
 750         env->worklist = worklist;
 751
 752         while (!waitq_empty(worklist)) {
 753                 ir_entity *ent = waitq_get(worklist);
 754
 755                 dump_global(env, ent, emit_commons);
 756         }
 757
 758         del_waitq(worklist);
 759         env->worklist = NULL;
 760 }
 761
 762 /************************************************************************/
 763
 764 /* Generate all entities. */
 765 void be_gas_emit_decls(be_emit_env_t *emit, const be_main_env_t *main_env,
 766                        int only_emit_marked_entities)
 767 {
 768         be_gas_decl_env_t env;
 769         obstack_t rodata, data, bss, ctor;
 770         int    size;
 771         char   *cp;
 772
 773         /* dump the global type */
 774         obstack_init(&rodata);
 775         obstack_init(&data);
 776         obstack_init(&bss);
 777         obstack_init(&ctor);
 778
 779         env.rodata_obst = &rodata;
 780         env.data_obst   = &data;
 781         env.bss_obst    = &bss;
 782         env.ctor_obst   = &ctor;
 783         env.main_env    = main_env;
 784
 785         be_gas_dump_globals(get_glob_type(), &env, 1, only_emit_marked_entities);
 786
 787         size = obstack_object_size(&data);
 788         cp   = obstack_finish(&data);
 789         if (size > 0) {
 790                 be_gas_emit_switch_section(emit, GAS_SECTION_DATA);
 791                 be_emit_string_len(emit, cp, size);
 792                 be_emit_write_line(emit);
 793         }
 794
 795         size = obstack_object_size(&rodata);
 796         cp   = obstack_finish(&rodata);
 797         if (size > 0) {
 798                 be_gas_emit_switch_section(emit, GAS_SECTION_RODATA);
 799                 be_emit_string_len(emit, cp, size);
 800                 be_emit_write_line(emit);
 801         }
 802
 803         size = obstack_object_size(&bss);
 804         cp   = obstack_finish(&bss);
 805         if (size > 0) {
 806                 be_gas_emit_switch_section(emit, GAS_SECTION_COMMON);
 807                 be_emit_string_len(emit, cp, size);
 808                 be_emit_write_line(emit);
 809         }
 810
 811         size = obstack_object_size(&ctor);
 812         cp   = obstack_finish(&ctor);
 813         if (size > 0) {
 814                 be_gas_emit_switch_section(emit, GAS_SECTION_CTOR);
 815                 be_emit_string_len(emit, cp, size);
 816                 be_emit_write_line(emit);
 817         }
 818
 819         obstack_free(&rodata, NULL);
 820         obstack_free(&data, NULL);
 821         obstack_free(&bss, NULL);
 822         obstack_free(&ctor, NULL);
 823
 824         /* dump the Thread Local Storage */
 825         obstack_init(&data);
 826
 827         env.rodata_obst = &data;
 828         env.data_obst   = &data;
 829         env.bss_obst    = &data;
 830         env.ctor_obst   = NULL;
 831
 832         be_gas_dump_globals(get_tls_type(), &env, 0, only_emit_marked_entities);
 833
 834         size = obstack_object_size(&data);
 835         cp   = obstack_finish(&data);
 836         if (size > 0) {
 837                 be_gas_emit_switch_section(emit, GAS_SECTION_TLS);
 838                 be_emit_cstring(emit, ".balign\t32\n");
 839                 be_emit_write_line(emit);
 840                 be_emit_string_len(emit, cp, size);
 841                 be_emit_write_line(emit);
 842         }
 843
 844         obstack_free(&data, NULL);
 845 }