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 #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 "entity_t.h"
  44 #include "error.h"
  45
  46 #include "be_t.h"
  47 #include "beemitter.h"
  48 #include "be_dbgout.h"
  49
  50 /** by default, we generate assembler code for the Linux gas */
  51 be_gas_flavour_t be_gas_flavour = GAS_FLAVOUR_ELF;
  52
  53 static be_gas_section_t current_section = (be_gas_section_t) -1;
  54 static int              force_section   = 0;
  55
  56 /**
  57  * Return the pseudo-instruction to be issued for a section switch
  58  * depending on the current flavour.
  59  *
  60  * @param section  the section to switch to
  61  *
  62  * @return  the pseudo-instruction
  63  */
  64 static const char *get_section_name(be_gas_section_t section) {
  65         static const char *text[GAS_FLAVOUR_LAST+1][GAS_SECTION_LAST+1] = {
  66                 { /* GAS_FLAVOUR_ELF */
  67                         ".section\t.text",
  68                         ".section\t.data",
  69                         ".section\t.rodata",
  70                         ".section\t.bss",
  71                         ".section\t.tbss,\"awT\",@nobits",
  72                         ".section\t.ctors,\"aw\",@progbits"
  73                 },
  74                 { /* GAS_FLAVOUR_MINGW */
  75                         ".section\t.text",
  76                         ".section\t.data",
  77                         ".section .rdata,\"dr\"",
  78                         ".section\t.bss",
  79                         ".section\t.tbss,\"awT\",@nobits",
  80                         ".section\t.ctors,\"aw\",@progbits"
  81                 },
  82                 { /* GAS_FLAVOUR_YASM */
  83                         ".section\t.text",
  84                         ".section\t.data",
  85                         ".section\t.rodata",
  86                         ".section\t.bss",
  87                         ".section\t.tbss,\"awT\",@nobits",
  88                         ".section\t.ctors,\"aw\",@progbits"
  89                 },
  90                 { /* GAS_FLAVOUR_MACH_O */
  91                         ".text",
  92                         ".data",
  93                         ".const",
  94                         ".data",
  95                         NULL, /* TLS is not supported on Mach-O */
  96                         NULL  /* constructors aren't marked with sections in Mach-O */
  97                 }
  98         };
  99
 100         assert((int) be_gas_flavour >= 0 && be_gas_flavour <= GAS_FLAVOUR_LAST);
 101         assert((int) section >= 0 && section <= GAS_SECTION_LAST);
 102         return text[be_gas_flavour][section];
 103 }
 104
 105 void be_gas_emit_switch_section(be_gas_section_t section) {
 106         if(current_section == section || force_section)
 107                 return;
 108
 109         be_emit_char('\t');
 110         be_emit_string(get_section_name(section));
 111         be_emit_char('\n');
 112         be_emit_write_line();
 113         current_section = section;
 114 }
 115
 116 void be_gas_emit_function_prolog(ir_entity *entity, unsigned alignment)
 117 {
 118         const char *name = get_entity_ld_name(entity);
 119
 120         be_gas_emit_switch_section(GAS_SECTION_TEXT);
 121
 122         /* write the begin line (used by scripts processing the assembler... */
 123         be_emit_write_line();
 124         be_emit_cstring("# -- Begin  ");
 125         be_emit_string(name);
 126         be_emit_char('\n');
 127         be_emit_write_line();
 128
 129         const char *fill_byte = "";
 130         /* gcc fills space between function with 0x90, no idea if this is needed */
 131         if(be_gas_flavour == GAS_FLAVOUR_MACH_O) {
 132                 fill_byte = "0x90";
 133         }
 134
 135         unsigned maximum_skip = (1 << alignment) - 1;
 136         be_emit_cstring("\t.p2align ");
 137         be_emit_irprintf("%u,%s,%u\n", alignment, fill_byte, maximum_skip);
 138         be_emit_write_line();
 139
 140         if (get_entity_visibility(entity) == visibility_external_visible) {
 141                 be_emit_cstring(".globl ");
 142                 be_emit_string(name);
 143                 be_emit_char('\n');
 144                 be_emit_write_line();
 145         }
 146
 147         switch (be_gas_flavour) {
 148         case GAS_FLAVOUR_ELF:
 149                 be_emit_cstring("\t.type\t");
 150                 be_emit_string(name);
 151                 be_emit_cstring(", @function\n");
 152                 be_emit_write_line();
 153                 break;
 154         case GAS_FLAVOUR_MINGW:
 155                 be_emit_cstring("\t.def\t");
 156                 be_emit_string(name);
 157                 be_emit_cstring(";\t.scl\t2;\t.type\t32;\t.endef\n");
 158                 be_emit_write_line();
 159                 break;
 160         case GAS_FLAVOUR_MACH_O:
 161         case GAS_FLAVOUR_YASM:
 162                 break;
 163         }
 164         be_emit_string(name);
 165         be_emit_cstring(":\n");
 166         be_emit_write_line();
 167 }
 168
 169 void be_gas_emit_function_epilog(ir_entity *entity)
 170 {
 171         const char *name = get_entity_ld_name(entity);
 172
 173         if (be_gas_flavour == GAS_FLAVOUR_ELF) {
 174                 be_emit_cstring("\t.size\t");
 175                 be_emit_string(name);
 176                 be_emit_cstring(", .-");
 177                 be_emit_string(name);
 178                 be_emit_char('\n');
 179                 be_emit_write_line();
 180         }
 181
 182         be_emit_cstring("# -- End  ");
 183         be_emit_string(name);
 184         be_emit_char('\n');
 185         be_emit_write_line();
 186 }
 187
 188 /**
 189  * An environment containing all needed dumper data.
 190  * Currently we create the file completely in memory first, then
 191  * write it to the disk. This is an artifact from the old C-generating backend
 192  * and even there NOT needed. So we might change it in the future.
 193  */
 194 typedef struct _be_gas_decl_env {
 195         const be_main_env_t *main_env; /**< The main backend environment, used for it's debug handle. */
 196         waitq     *worklist;           /**< A worklist we use to place not yet handled entities on. */
 197 } be_gas_decl_env_t;
 198
 199 /************************************************************************/
 200
 201 /**
 202  * Output a tarval.
 203  *
 204  * @param tv     the tarval
 205  * @param bytes  the width of the tarvals value in bytes
 206  */
 207 static void dump_arith_tarval(tarval *tv, int bytes)
 208 {
 209         switch (bytes) {
 210         case 1:
 211                 be_emit_irprintf("0x%02x", get_tarval_sub_bits(tv, 0));
 212                 break;
 213
 214         case 2:
 215                 be_emit_irprintf("0x%02x%02x", get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 216                 break;
 217
 218         case 4:
 219                 be_emit_irprintf("0x%02x%02x%02x%02x",
 220                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 221                 break;
 222
 223         case 8:
 224                 be_emit_irprintf("0x%02x%02x%02x%02x%02x%02x%02x%02x",
 225                         get_tarval_sub_bits(tv, 7), get_tarval_sub_bits(tv, 6), get_tarval_sub_bits(tv, 5), get_tarval_sub_bits(tv, 4),
 226                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 227                 break;
 228
 229         case 10:
 230         case 12:
 231                 break;
 232
 233         case 16:
 234                 be_emit_irprintf("0x%02x%02x%02x%02x%02x%02x%02x%02x"
 235                                                "%02x%02x%02x%02x%02x%02x%02x%02x",
 236                         get_tarval_sub_bits(tv, 15), get_tarval_sub_bits(tv, 16),
 237                         get_tarval_sub_bits(tv, 13), get_tarval_sub_bits(tv, 12),
 238                         get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
 239                         get_tarval_sub_bits(tv, 9), get_tarval_sub_bits(tv, 8),
 240                         get_tarval_sub_bits(tv, 7), get_tarval_sub_bits(tv, 6),
 241                         get_tarval_sub_bits(tv, 5), get_tarval_sub_bits(tv, 4),
 242                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2),
 243                         get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 244                 break;
 245
 246
 247         default:
 248                 fprintf(stderr, "Try to dump an tarval with %d bytes\n", bytes);
 249                 assert(0);
 250         }
 251 }
 252
 253 /**
 254  * Return the label prefix for labeled blocks.
 255  */
 256 const char *be_gas_label_prefix(void) {
 257         return ".LG";
 258 }
 259
 260 /**
 261  * Dump a label.
 262  */
 263 static void dump_label(ir_label_t label) {
 264         be_emit_irprintf("%s%ld", be_gas_label_prefix(), label);
 265 }
 266
 267 /**
 268  * Return the tarval of an atomic initializer.
 269  *
 270  * @param init  a node representing the initializer (on the const code irg)
 271  *
 272  * @return the tarval
 273  */
 274 static tarval *get_atomic_init_tv(ir_node *init)
 275 {
 276         for (;;) {
 277                 ir_mode *mode = get_irn_mode(init);
 278
 279                 switch (get_irn_opcode(init)) {
 280
 281                 case iro_Cast:
 282                         init = get_Cast_op(init);
 283                         continue;
 284
 285                 case iro_Conv:
 286                         init = get_Conv_op(init);
 287                         continue;
 288
 289                 case iro_Const:
 290                         return get_Const_tarval(init);
 291
 292                 case iro_SymConst:
 293                         switch (get_SymConst_kind(init)) {
 294                         case symconst_type_size:
 295                                 return new_tarval_from_long(get_type_size_bytes(get_SymConst_type(init)), mode);
 296
 297                         case symconst_type_align:
 298                                 return new_tarval_from_long(get_type_alignment_bytes(get_SymConst_type(init)), mode);
 299
 300                         case symconst_ofs_ent:
 301                                 return new_tarval_from_long(get_entity_offset(get_SymConst_entity(init)), mode);
 302
 303                         case symconst_enum_const:
 304                                 return get_enumeration_value(get_SymConst_enum(init));
 305
 306                         case symconst_label:
 307                                 return NULL;
 308
 309                         default:
 310                                 return NULL;
 311                         }
 312
 313                 default:
 314                         return NULL;
 315                 }
 316         }
 317 }
 318
 319 /**
 320  * Dump an atomic value.
 321  *
 322  * @param env   the gas output environment
 323  * @param init  a node representing the atomic value (on the const code irg)
 324  */
 325 static void do_dump_atomic_init(be_gas_decl_env_t *env, ir_node *init)
 326 {
 327         ir_mode *mode = get_irn_mode(init);
 328         int bytes     = get_mode_size_bytes(mode);
 329         tarval *tv;
 330         ir_label_t label;
 331         ir_entity *ent;
 332
 333         init = skip_Id(init);
 334
 335         switch (get_irn_opcode(init)) {
 336         case iro_Cast:
 337                 do_dump_atomic_init(env, get_Cast_op(init));
 338                 return;
 339
 340         case iro_Conv:
 341                 do_dump_atomic_init(env, get_Conv_op(init));
 342                 return;
 343
 344         case iro_Const:
 345                 tv = get_Const_tarval(init);
 346
 347                 /* it's a arithmetic value */
 348                 dump_arith_tarval(tv, bytes);
 349                 return;
 350
 351         case iro_SymConst:
 352                 switch (get_SymConst_kind(init)) {
 353                 case symconst_addr_name:
 354                         be_emit_ident(get_SymConst_name(init));
 355                         break;
 356
 357                 case symconst_addr_ent:
 358                         ent = get_SymConst_entity(init);
 359                         if(!is_entity_backend_marked(ent)) {
 360                                 waitq_put(env->worklist, ent);
 361                                 set_entity_backend_marked(ent, 1);
 362                         }
 363                         be_emit_ident(get_entity_ld_ident(ent));
 364                         break;
 365
 366                 case symconst_ofs_ent:
 367                         ent = get_SymConst_entity(init);
 368 #if 0       /* not needed, is it? */
 369                         if(!is_entity_backend_marked(ent)) {
 370                                 waitq_put(env->worklist, ent);
 371                                 set_entity_backend_marked(ent, 1);
 372                         }
 373 #endif
 374                         be_emit_irprintf("%d", get_entity_offset(ent));
 375                         break;
 376
 377                 case symconst_type_size:
 378                         be_emit_irprintf("%u", get_type_size_bytes(get_SymConst_type(init)));
 379                         break;
 380
 381                 case symconst_type_align:
 382                         be_emit_irprintf("%u", get_type_alignment_bytes(get_SymConst_type(init)));
 383                         break;
 384
 385                 case symconst_enum_const:
 386                         tv = get_enumeration_value(get_SymConst_enum(init));
 387                         dump_arith_tarval(tv, bytes);
 388                         break;
 389
 390                 case symconst_label:
 391                         label = get_SymConst_label(init);
 392                         dump_label(label);
 393                         break;
 394
 395                 default:
 396                         assert(!"dump_atomic_init(): don't know how to init from this SymConst");
 397                 }
 398                 return;
 399
 400                 case iro_Add:
 401                         do_dump_atomic_init(env, get_Add_left(init));
 402                         be_emit_cstring(" + ");
 403                         do_dump_atomic_init(env, get_Add_right(init));
 404                         return;
 405
 406                 case iro_Sub:
 407                         do_dump_atomic_init(env, get_Sub_left(init));
 408                         be_emit_cstring(" - ");
 409                         do_dump_atomic_init(env, get_Sub_right(init));
 410                         return;
 411
 412                 case iro_Mul:
 413                         do_dump_atomic_init(env, get_Mul_left(init));
 414                         be_emit_cstring(" * ");
 415                         do_dump_atomic_init(env, get_Mul_right(init));
 416                         return;
 417
 418                 default:
 419                         assert(0 && "dump_atomic_init(): unknown IR-node");
 420         }
 421 }
 422
 423 /**
 424  * Dumps the type for given size (.byte, .long, ...)
 425  *
 426  * @param size  the size in bytes
 427  */
 428 static void dump_size_type(size_t size) {
 429         switch (size) {
 430         case 1:
 431                 be_emit_cstring("\t.byte\t");
 432                 break;
 433
 434         case 2:
 435                 be_emit_cstring("\t.word\t");
 436                 break;
 437
 438         case 4:
 439                 be_emit_cstring("\t.long\t");
 440                 break;
 441
 442         case 8:
 443                 be_emit_cstring("\t.quad\t");
 444                 break;
 445
 446         case 10:
 447         case 12:
 448                 /* handled in arith */
 449                 break;
 450
 451         case 16:
 452                 be_emit_cstring("\t.octa\t");
 453                 break;
 454
 455         default:
 456                 panic("Try to dump a type with %u bytes\n", (unsigned) size);
 457         }
 458 }
 459
 460 /**
 461  * Emit an atomic value.
 462  *
 463  * @param env   the gas output environment
 464  * @param init  a node representing the atomic value (on the const code irg)
 465  */
 466 static void dump_atomic_init(be_gas_decl_env_t *env, ir_node *init)
 467 {
 468         ir_mode *mode = get_irn_mode(init);
 469         int bytes     = get_mode_size_bytes(mode);
 470
 471         dump_size_type(bytes);
 472         do_dump_atomic_init(env, init);
 473         be_emit_char('\n');
 474         be_emit_write_line();
 475 }
 476
 477 /************************************************************************/
 478 /* Routines to dump global variables                                    */
 479 /************************************************************************/
 480
 481 static int initializer_is_string_const(const ir_initializer_t *initializer)
 482 {
 483         size_t i, len;
 484
 485         if(initializer->kind != IR_INITIALIZER_COMPOUND)
 486                 return 0;
 487
 488         len = initializer->compound.n_initializers;
 489         if (len < 1)
 490                 return 0;
 491         for(i = 0; i < len; ++i) {
 492                 int               c;
 493                 tarval           *tv;
 494                 ir_mode          *mode;
 495                 ir_initializer_t *sub_initializer
 496                         = initializer->compound.initializers[i];
 497
 498                 if(sub_initializer->kind != IR_INITIALIZER_TARVAL)
 499                         return 0;
 500
 501                 tv   = sub_initializer->tarval.value;
 502                 mode = get_tarval_mode(tv);
 503
 504                 if (!mode_is_int(mode)
 505                                 || get_mode_size_bits(mode) != get_mode_size_bits(mode_Bs))
 506                         return 0;
 507
 508                 c = get_tarval_long(tv);
 509                 if (i < len - 1) {
 510                         if (!isgraph(c) && !isspace(c))
 511                                 return 0;
 512                 } else {
 513                         if (c != 0)
 514                                 return 0;
 515                 }
 516         }
 517
 518         return 1;
 519 }
 520
 521 /**
 522  * Determine if an entity is a string constant
 523  * @param ent The entity
 524  * @return 1 if it is a string constant, 0 otherwise
 525  */
 526 static int ent_is_string_const(ir_entity *ent)
 527 {
 528         ir_type *type, *element_type;
 529         ir_mode *mode;
 530         int i, c, n;
 531
 532         type = get_entity_type(ent);
 533
 534         /* if it's an array */
 535         if (!is_Array_type(type))
 536                 return 0;
 537
 538         element_type = get_array_element_type(type);
 539
 540         /* and the array's element type is primitive */
 541         if (!is_Primitive_type(element_type))
 542                 return 0;
 543
 544         /* and the mode of the element type is an int of
 545          * the same size as the byte mode */
 546         mode = get_type_mode(element_type);
 547         if (!mode_is_int(mode)
 548                 || get_mode_size_bits(mode) != get_mode_size_bits(mode_Bs))
 549                 return 0;
 550
 551         if(ent->has_initializer) {
 552                 /* TODO */
 553                 return 0;
 554         } else {
 555                 /* if it contains only printable chars and a 0 at the end */
 556                 n = get_compound_ent_n_values(ent);
 557                 for (i = 0; i < n; ++i) {
 558                         ir_node *irn = get_compound_ent_value(ent, i);
 559                         if (! is_Const(irn))
 560                                 return 0;
 561
 562                         c = (int) get_tarval_long(get_Const_tarval(irn));
 563
 564                         if((i < n - 1 && !(isgraph(c) || isspace(c)))
 565                                         || (i == n - 1 && c != '\0'))
 566                                 return 0;
 567                 }
 568         }
 569
 570         /* then we can emit it as a string constant */
 571         return 1;
 572 }
 573
 574 /**
 575  * Dump a string constant.
 576  * No checks are made!!
 577  *
 578  * @param ent  The entity to dump.
 579  */
 580 static void dump_string_cst(ir_entity *ent)
 581 {
 582         int      i, len;
 583         ir_type *type;
 584         int      type_size;
 585         int      remaining_space;
 586
 587         be_gas_section_t last_section = current_section;
 588         len = get_compound_ent_n_values(ent);
 589         if (be_gas_flavour == GAS_FLAVOUR_MACH_O) {
 590                 if (get_entity_variability(ent) == variability_constant) {
 591                         be_gas_emit_switch_section(GAS_SECTION_CSTRING);
 592                 }
 593                 be_emit_cstring("\t.ascii \"");
 594         } else {
 595                 be_emit_cstring("\t.string \"");
 596                 len -= 1;
 597         }
 598
 599         for (i = 0; i < len; ++i) {
 600                 ir_node *irn;
 601                 int c;
 602
 603                 irn = get_compound_ent_value(ent, i);
 604                 c = (int) get_tarval_long(get_Const_tarval(irn));
 605
 606                 switch (c) {
 607                 case '"' : be_emit_cstring("\\\""); break;
 608                 case '\n': be_emit_cstring("\\n"); break;
 609                 case '\r': be_emit_cstring("\\r"); break;
 610                 case '\t': be_emit_cstring("\\t"); break;
 611                 case '\\': be_emit_cstring("\\\\"); break;
 612                 default  :
 613                         if (isprint(c))
 614                                 be_emit_char(c);
 615                         else
 616                                 be_emit_irprintf("\\%o", c);
 617                         break;
 618                 }
 619         }
 620         be_emit_cstring("\"\n");
 621         be_emit_write_line();
 622
 623         type            = get_entity_type(ent);
 624         type_size       = get_type_size_bytes(type);
 625         remaining_space = type_size - len;
 626         assert(remaining_space >= 0);
 627         if(remaining_space > 0) {
 628                 be_emit_irprintf("\t.skip\t%d\n", remaining_space);
 629         }
 630         if(be_gas_flavour == GAS_FLAVOUR_MACH_O) {
 631                 be_gas_emit_switch_section(last_section);
 632         }
 633 }
 634
 635 static void dump_string_initializer(const ir_initializer_t *initializer)
 636 {
 637         size_t i, len;
 638
 639         len = initializer->compound.n_initializers;
 640         if(be_gas_flavour == GAS_FLAVOUR_MACH_O) {
 641                 be_emit_cstring("\t.string \"");
 642                 len -= 1;
 643         } else {
 644                 be_emit_cstring("\t.ascii \"");
 645         }
 646
 647         for(i = 0; i < len; ++i) {
 648                 const ir_initializer_t *sub_initializer
 649                         = get_initializer_compound_value(initializer, i);
 650
 651                 tarval *tv = get_initializer_tarval_value(sub_initializer);
 652                 int     c  = get_tarval_long(tv);
 653
 654                 switch (c) {
 655                 case '"' : be_emit_cstring("\\\""); break;
 656                 case '\n': be_emit_cstring("\\n"); break;
 657                 case '\r': be_emit_cstring("\\r"); break;
 658                 case '\t': be_emit_cstring("\\t"); break;
 659                 case '\\': be_emit_cstring("\\\\"); break;
 660                 default  :
 661                         if (isprint(c))
 662                                 be_emit_char(c);
 663                         else
 664                                 be_emit_irprintf("\\%o", c);
 665                         break;
 666                 }
 667         }
 668         be_emit_cstring("\"\n");
 669         be_emit_write_line();
 670 }
 671
 672 enum normal_or_bitfield_kind {
 673         NORMAL = 0,
 674         TARVAL,
 675         BITFIELD
 676 };
 677
 678 typedef struct {
 679         enum normal_or_bitfield_kind kind;
 680         union {
 681                 ir_node       *value;
 682                 tarval        *tarval;
 683                 unsigned char  bf_val;
 684         } v;
 685 } normal_or_bitfield;
 686
 687 static int is_type_variable_size(ir_type *type)
 688 {
 689         (void) type;
 690         /* TODO */
 691         return 0;
 692 }
 693
 694 static size_t get_initializer_size(const ir_initializer_t *initializer,
 695                                    ir_type *type)
 696 {
 697         switch(get_initializer_kind(initializer)) {
 698         case IR_INITIALIZER_TARVAL: {
 699                 assert(get_tarval_mode(get_initializer_tarval_value(initializer)) == get_type_mode(type));
 700                 return get_type_size_bytes(type);
 701         }
 702         case IR_INITIALIZER_CONST:
 703         case IR_INITIALIZER_NULL:
 704                 return get_type_size_bytes(type);
 705         case IR_INITIALIZER_COMPOUND: {
 706                 if(!is_type_variable_size(type)) {
 707                         return get_type_size_bytes(type);
 708                 } else {
 709                         unsigned n_entries
 710                                 = get_initializer_compound_n_entries(initializer);
 711                         unsigned i;
 712                         unsigned initializer_size = get_type_size_bytes(type);
 713                         for(i = 0; i < n_entries; ++i) {
 714                                 ir_entity *entity = get_compound_member(type, i);
 715                                 ir_type   *type   = get_entity_type(entity);
 716
 717                                 const ir_initializer_t *sub_initializer
 718                                         = get_initializer_compound_value(initializer, i);
 719
 720                                 unsigned offset = get_entity_offset(entity);
 721                                 unsigned size   = get_initializer_size(sub_initializer, type);
 722
 723                                 if(offset + size > initializer_size) {
 724                                         initializer_size = offset + size;
 725                                 }
 726                         }
 727                         return initializer_size;
 728                 }
 729         }
 730         }
 731
 732         panic("found invalid initializer");
 733 }
 734
 735 #ifndef NDEBUG
 736 static normal_or_bitfield *glob_vals;
 737 static size_t              max_vals;
 738 #endif
 739
 740 static void dump_bitfield(normal_or_bitfield *vals, size_t offset_bits,
 741                           const ir_initializer_t *initializer, ir_type *type)
 742 {
 743         unsigned char  last_bits = 0;
 744         ir_mode       *mode      = get_type_mode(type);
 745         tarval        *tv        = NULL;
 746         unsigned char  curr_bits;
 747         int            value_len;
 748         int            j;
 749
 750         switch(get_initializer_kind(initializer)) {
 751         case IR_INITIALIZER_NULL:
 752                 return;
 753         case IR_INITIALIZER_TARVAL:
 754                 tv = get_initializer_tarval_value(initializer);
 755                 break;
 756         case IR_INITIALIZER_CONST: {
 757                 ir_node *node = get_initializer_const_value(initializer);
 758                 if(!is_Const(node)) {
 759                         panic("bitfield initializer not a Const node");
 760                 }
 761                 tv = get_Const_tarval(node);
 762                 break;
 763         }
 764         case IR_INITIALIZER_COMPOUND:
 765                 panic("bitfield initializer is compound");
 766         }
 767         if (tv == NULL) {
 768                 panic("Couldn't get numeric value for bitfield initializer\n");
 769         }
 770
 771         /* normalize offset */
 772         vals        += offset_bits >> 3;
 773         offset_bits &= 7;
 774         value_len    = get_mode_size_bits(mode);
 775
 776         /* combine bits with existing bits */
 777         for (j = 0; value_len + (int) offset_bits > 0; ++j) {
 778                 assert((size_t) (vals - glob_vals) + j < max_vals);
 779                 assert(vals[j].kind == BITFIELD ||
 780                                 (vals[j].kind == NORMAL && vals[j].v.value == NULL));
 781                 vals[j].kind = BITFIELD;
 782                 curr_bits    = get_tarval_sub_bits(tv, j);
 783                 vals[j].v.bf_val
 784                         |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
 785                 value_len -= 8;
 786                 last_bits = curr_bits;
 787         }
 788 }
 789
 790 static void dump_ir_initializer(normal_or_bitfield *vals,
 791                                 const ir_initializer_t *initializer,
 792                                 ir_type *type)
 793 {
 794         assert((size_t) (vals - glob_vals) < max_vals);
 795
 796         switch(get_initializer_kind(initializer)) {
 797         case IR_INITIALIZER_NULL:
 798                 return;
 799         case IR_INITIALIZER_TARVAL: {
 800                 size_t i;
 801
 802                 assert(vals->kind != BITFIELD);
 803                 vals->kind     = TARVAL;
 804                 vals->v.tarval = get_initializer_tarval_value(initializer);
 805                 assert(get_type_mode(type) == get_tarval_mode(vals->v.tarval));
 806                 for(i = 1; i < get_type_size_bytes(type); ++i) {
 807                         vals[i].kind    = NORMAL;
 808                         vals[i].v.value = NULL;
 809                 }
 810                 return;
 811         }
 812         case IR_INITIALIZER_CONST: {
 813                 size_t i;
 814
 815                 assert(vals->kind != BITFIELD);
 816                 vals->kind    = NORMAL;
 817                 vals->v.value = get_initializer_const_value(initializer);
 818                 for(i = 1; i < get_type_size_bytes(type); ++i) {
 819                         vals[i].kind    = NORMAL;
 820                         vals[i].v.value = NULL;
 821                 }
 822                 return;
 823         }
 824         case IR_INITIALIZER_COMPOUND: {
 825                 size_t i = 0;
 826                 size_t n = get_initializer_compound_n_entries(initializer);
 827
 828                 if(is_Array_type(type)) {
 829                         ir_type *element_type = get_array_element_type(type);
 830                         size_t   skip         = get_type_size_bytes(element_type);
 831                         size_t   alignment    = get_type_alignment_bytes(element_type);
 832                         size_t   misalign     = skip % alignment;
 833                         if(misalign != 0) {
 834                                 skip += alignment - misalign;
 835                         }
 836
 837                         for(i = 0; i < n; ++i) {
 838                                 ir_initializer_t *sub_initializer
 839                                         = get_initializer_compound_value(initializer, i);
 840
 841                                 dump_ir_initializer(vals, sub_initializer, element_type);
 842
 843                                 vals += skip;
 844                         }
 845                 } else {
 846                         size_t n_members, i;
 847                         assert(is_compound_type(type));
 848                         n_members = get_compound_n_members(type);
 849                         for(i = 0; i < n_members; ++i) {
 850                                 ir_entity        *member    = get_compound_member(type, i);
 851                                 size_t            offset    = get_entity_offset(member);
 852                                 ir_type          *subtype   = get_entity_type(member);
 853                                 ir_mode          *mode      = get_type_mode(subtype);
 854                                 ir_initializer_t *sub_initializer;
 855
 856                                 assert(i < get_initializer_compound_n_entries(initializer));
 857                                 sub_initializer
 858                                         = get_initializer_compound_value(initializer, i);
 859
 860                                 if(mode != NULL) {
 861                                         size_t offset_bits
 862                                                 = get_entity_offset_bits_remainder(member);
 863                                         size_t value_len   = get_mode_size_bits(mode);
 864
 865                                         if(offset_bits != 0 ||
 866                                                 (value_len != 8 && value_len != 16 && value_len != 32
 867                                                  && value_len != 64)) {
 868                                                 dump_bitfield(&vals[offset], offset_bits,
 869                                                               sub_initializer, subtype);
 870                                                 continue;
 871                                         }
 872                                 }
 873
 874                                 dump_ir_initializer(&vals[offset], sub_initializer, subtype);
 875                         }
 876                 }
 877
 878                 return;
 879         }
 880         }
 881         panic("invalid ir_initializer kind found");
 882 }
 883
 884 static void dump_initializer(be_gas_decl_env_t *env, ir_entity *entity)
 885 {
 886         const ir_initializer_t *initializer = entity->attr.initializer;
 887         ir_type                *type;
 888         normal_or_bitfield     *vals;
 889         size_t                  size;
 890         size_t                  k;
 891
 892         if(initializer_is_string_const(initializer)) {
 893                 dump_string_initializer(initializer);
 894                 return;
 895         }
 896
 897         type = get_entity_type(entity);
 898         size = get_initializer_size(initializer, type);
 899
 900         if (size == 0)
 901                 return;
 902
 903         /*
 904          * In the worst case, every initializer allocates one byte.
 905          * Moreover, initializer might be big, do not allocate on stack.
 906          */
 907         vals = xcalloc(size, sizeof(vals[0]));
 908
 909 #ifndef NDEBUG
 910         glob_vals = vals;
 911         max_vals  = size;
 912 #endif
 913
 914         dump_ir_initializer(vals, initializer, type);
 915
 916         /* now write values sorted */
 917         for (k = 0; k < size; ) {
 918                 int space = 0, skip = 0;
 919                 if (vals[k].kind == NORMAL) {
 920                         if(vals[k].v.value != NULL) {
 921                                 dump_atomic_init(env, vals[k].v.value);
 922                                 skip = get_mode_size_bytes(get_irn_mode(vals[k].v.value)) - 1;
 923                         } else {
 924                                 space = 1;
 925                         }
 926                 } else if(vals[k].kind == TARVAL) {
 927                         tarval *tv   = vals[k].v.tarval;
 928                         size_t  size = get_mode_size_bytes(get_tarval_mode(tv));
 929
 930                         assert(tv != NULL);
 931
 932                         skip = size - 1;
 933                         dump_size_type(size);
 934                         dump_arith_tarval(tv, size);
 935                         be_emit_char('\n');
 936                         be_emit_write_line();
 937                 } else {
 938                         assert(vals[k].kind == BITFIELD);
 939                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
 940                         be_emit_write_line();
 941                 }
 942
 943                 ++k;
 944                 while (k < size && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
 945                         ++space;
 946                         ++k;
 947                 }
 948                 space -= skip;
 949                 assert(space >= 0);
 950
 951                 /* a gap */
 952                 if (space > 0) {
 953                         be_emit_irprintf("\t.skip\t%d\n", space);
 954                         be_emit_write_line();
 955                 }
 956         }
 957         xfree(vals);
 958 }
 959
 960 /**
 961  * Dump an initializer for a compound entity.
 962  */
 963 static void dump_compound_init(be_gas_decl_env_t *env, ir_entity *ent)
 964 {
 965         normal_or_bitfield *vals;
 966         int i, j, n;
 967         unsigned k, last_ofs;
 968
 969         if(ent->has_initializer) {
 970                 dump_initializer(env, ent);
 971                 return;
 972         }
 973
 974         n = get_compound_ent_n_values(ent);
 975
 976         /* Find the initializer size. Sorrily gcc support a nasty feature:
 977            The last field of a compound may be a flexible array. This allows
 978            initializers bigger than the type size. */
 979         last_ofs = get_type_size_bytes(get_entity_type(ent));
 980         for (i = 0; i < n; ++i) {
 981                 unsigned offset         = get_compound_ent_value_offset_bytes(ent, i);
 982                 unsigned bits_remainder = get_compound_ent_value_offset_bit_remainder(ent, i);
 983                 ir_node  *value         = get_compound_ent_value(ent, i);
 984                 unsigned value_len      = get_mode_size_bits(get_irn_mode(value));
 985
 986                 offset += (value_len + bits_remainder + 7) >> 3;
 987
 988                 if (offset > last_ofs) {
 989                         last_ofs = offset;
 990                 }
 991         }
 992
 993         /*
 994          * In the worst case, every initializer allocates one byte.
 995          * Moreover, initializer might be big, do not allocate on stack.
 996          */
 997         vals = xcalloc(last_ofs, sizeof(vals[0]));
 998
 999         /* collect the values and store them at the offsets */
1000         for (i = 0; i < n; ++i) {
1001                 unsigned offset      = get_compound_ent_value_offset_bytes(ent, i);
1002                 int      offset_bits = get_compound_ent_value_offset_bit_remainder(ent, i);
1003                 ir_node  *value      = get_compound_ent_value(ent, i);
1004                 int      value_len   = get_mode_size_bits(get_irn_mode(value));
1005
1006                 assert(offset_bits >= 0);
1007
1008                 if (offset_bits != 0 ||
1009                         (value_len != 8 && value_len != 16 && value_len != 32 && value_len != 64)) {
1010                         tarval *tv = get_atomic_init_tv(value);
1011                         unsigned char curr_bits, last_bits = 0;
1012                         if (tv == NULL) {
1013                                 panic("Couldn't get numeric value for bitfield initializer '%s'\n",
1014                                       get_entity_ld_name(ent));
1015                         }
1016                         /* normalize offset */
1017                         offset += offset_bits >> 3;
1018                         offset_bits &= 7;
1019
1020                         for (j = 0; value_len + offset_bits > 0; ++j) {
1021                                 assert(offset + j < last_ofs);
1022                                 assert(vals[offset + j].kind == BITFIELD || vals[offset + j].v.value == NULL);
1023                                 vals[offset + j].kind = BITFIELD;
1024                                 curr_bits = get_tarval_sub_bits(tv, j);
1025                                 vals[offset + j].v.bf_val |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
1026                                 value_len -= 8;
1027                                 last_bits = curr_bits;
1028                         }
1029                 } else {
1030                         int i;
1031
1032                         assert(offset < last_ofs);
1033                         assert(vals[offset].kind == NORMAL);
1034                         for (i = 1; i < value_len / 8; ++i) {
1035                                 assert(vals[offset + i].v.value == NULL);
1036                         }
1037                         vals[offset].v.value = value;
1038                 }
1039         }
1040
1041         /* now write them sorted */
1042         for (k = 0; k < last_ofs; ) {
1043                 int space = 0, skip = 0;
1044                 if (vals[k].kind == NORMAL) {
1045                         if(vals[k].v.value != NULL) {
1046                                 dump_atomic_init(env, vals[k].v.value);
1047                                 skip = get_mode_size_bytes(get_irn_mode(vals[k].v.value)) - 1;
1048                         } else {
1049                                 space = 1;
1050                         }
1051                 } else {
1052                         assert(vals[k].kind == BITFIELD);
1053                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
1054                 }
1055
1056                 ++k;
1057                 while (k < last_ofs && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
1058                         ++space;
1059                         ++k;
1060                 }
1061                 space -= skip;
1062                 assert(space >= 0);
1063
1064                 /* a gap */
1065                 if (space > 0) {
1066                         be_emit_irprintf("\t.skip\t%d\n", space);
1067                         be_emit_write_line();
1068                 }
1069         }
1070         xfree(vals);
1071 }
1072
1073 static void emit_align(unsigned alignment)
1074 {
1075         if (!is_po2(alignment))
1076                 panic("alignment not a power of 2");
1077
1078         be_emit_irprintf(".p2align\t%u\n", log2_floor(alignment));
1079         be_emit_write_line();
1080 }
1081
1082 /**
1083  * Dump a global entity.
1084  *
1085  * @param env           the gas output environment
1086  * @param ent           the entity to be dumped
1087  * @param emit_commons  if non-zero, emit commons (non-local uninitialized entities)
1088  */
1089 static void dump_global(be_gas_decl_env_t *env, ir_entity *ent, int emit_commons)
1090 {
1091         ir_type          *type           = get_entity_type(ent);
1092         ident            *ld_ident       = get_entity_ld_ident(ent);
1093         unsigned          align          = get_type_alignment_bytes(type);
1094         int               emit_as_common = 0;
1095         be_gas_section_t  section;
1096         ir_variability    variability;
1097         ir_visibility     visibility;
1098
1099         if (is_Method_type(type)) {
1100                 if (be_gas_flavour != GAS_FLAVOUR_MACH_O
1101                                 && get_method_img_section(ent) == section_constructors) {
1102                         be_gas_emit_switch_section(GAS_SECTION_CTOR);
1103                         emit_align(align);
1104                         dump_size_type(align);
1105                         be_emit_ident(ld_ident);
1106                         be_emit_char('\n');
1107                         be_emit_write_line();
1108                 }
1109
1110                 return;
1111         }
1112
1113         variability = get_entity_variability(ent);
1114         visibility  = get_entity_visibility(ent);
1115         section     = GAS_SECTION_DATA;
1116         if (variability == variability_constant) {
1117                 /* a constant entity, put it on the rdata */
1118                 section = GAS_SECTION_RODATA;
1119         } else if (variability == variability_uninitialized) {
1120                 /* uninitialized entity put it in bss segment */
1121                 section = GAS_SECTION_COMMON;
1122                 if (emit_commons && visibility != visibility_local)
1123                         emit_as_common = 1;
1124         }
1125
1126         if(!emit_as_common) {
1127                 be_gas_emit_switch_section(section);
1128         }
1129
1130         be_dbg_variable(ent);
1131
1132         /* global or not global */
1133         if (visibility == visibility_external_visible && !emit_as_common) {
1134                 be_emit_cstring(".globl\t");
1135                 be_emit_ident(ld_ident);
1136                 be_emit_char('\n');
1137                 be_emit_write_line();
1138         } else if(visibility == visibility_external_allocated) {
1139                 be_emit_cstring(".globl\t");
1140                 be_emit_ident(ld_ident);
1141                 be_emit_char('\n');
1142                 be_emit_write_line();
1143                 /* we can return now... */
1144                 return;
1145         }
1146         /* alignment */
1147         if (align > 1 && !emit_as_common) {
1148                 emit_align(align);
1149         }
1150
1151         if (!emit_as_common) {
1152                 be_emit_ident(ld_ident);
1153                 be_emit_cstring(":\n");
1154                 be_emit_write_line();
1155         }
1156
1157         if (variability == variability_uninitialized) {
1158                 if (emit_as_common) {
1159                         switch (be_gas_flavour) {
1160                         case GAS_FLAVOUR_ELF:
1161                         case GAS_FLAVOUR_MACH_O:
1162                         case GAS_FLAVOUR_YASM:
1163                                 be_emit_irprintf("\t.comm %s,%u,%u\n",
1164                                         get_id_str(ld_ident), get_type_size_bytes(type), align);
1165                                 be_emit_write_line();
1166                                 break;
1167                         case GAS_FLAVOUR_MINGW:
1168                                 be_emit_irprintf("\t.comm %s,%u # %u\n",
1169                                         get_id_str(ld_ident), get_type_size_bytes(type), align);
1170                                 be_emit_write_line();
1171                                 break;
1172                         }
1173                 } else {
1174                         be_emit_irprintf("\t.zero %u\n", get_type_size_bytes(type));
1175                         be_emit_write_line();
1176                 }
1177         } else {
1178                 if (is_atomic_entity(ent)) {
1179                         dump_atomic_init(env, get_atomic_ent_value(ent));
1180                 } else {
1181                         /* sort_compound_ent_values(ent); */
1182
1183                         switch (get_type_tpop_code(get_entity_type(ent))) {
1184                         case tpo_array:
1185                                 if (ent_is_string_const(ent))
1186                                         dump_string_cst(ent);
1187                                 else
1188                                         dump_compound_init(env, ent);
1189                                 break;
1190                         case tpo_struct:
1191                         case tpo_class:
1192                         case tpo_union:
1193                                 dump_compound_init(env, ent);
1194                                 break;
1195                         default:
1196                                 assert(0);
1197                         }
1198                 }
1199         }
1200 }
1201
1202 /**
1203  * Dumps declarations of global variables and the initialization code.
1204  *
1205  * @param gt                a global like type, either the global or the TLS one
1206  * @param env               an environment
1207  * @param emit_commons      if non-zero, emit commons (non-local uninitialized entities)
1208  * @param only_emit_marked  if non-zero, external allocated entities that do not have
1209  *                          its visited flag set are ignored
1210  */
1211 static void be_gas_dump_globals(ir_type *gt, be_gas_decl_env_t *env,
1212                               int emit_commons, int only_emit_marked)
1213 {
1214         int i, n = get_compound_n_members(gt);
1215         waitq *worklist = new_waitq();
1216
1217         if (only_emit_marked) {
1218                 for (i = 0; i < n; i++) {
1219                         ir_entity *ent = get_compound_member(gt, i);
1220                         if (is_entity_backend_marked(ent) ||
1221                             get_entity_visibility(ent) != visibility_external_allocated) {
1222                                 waitq_put(worklist, ent);
1223                                 set_entity_backend_marked(ent, 1);
1224                         }
1225                 }
1226         } else {
1227                 for (i = 0; i < n; i++) {
1228                         ir_entity *ent = get_compound_member(gt, i);
1229                         set_entity_backend_marked(ent, 1);
1230                         waitq_put(worklist, ent);
1231                 }
1232         }
1233
1234         env->worklist = worklist;
1235
1236         while (!waitq_empty(worklist)) {
1237                 ir_entity *ent = waitq_get(worklist);
1238
1239                 dump_global(env, ent, emit_commons);
1240         }
1241
1242         del_waitq(worklist);
1243         env->worklist = NULL;
1244 }
1245
1246 /************************************************************************/
1247
1248 /* Generate all entities. */
1249 void be_gas_emit_decls(const be_main_env_t *main_env,
1250                        int only_emit_marked_entities)
1251 {
1252         be_gas_decl_env_t env;
1253
1254         env.main_env = main_env;
1255
1256         /* dump global type */
1257         be_gas_dump_globals(get_glob_type(), &env, 1, only_emit_marked_entities);
1258
1259         /* dump the Thread Local Storage */
1260         if (be_gas_flavour != GAS_FLAVOUR_MACH_O) {
1261                 be_gas_emit_switch_section(GAS_SECTION_TLS);
1262                 force_section = 1;
1263                 be_gas_dump_globals(get_tls_type(), &env, 0, only_emit_marked_entities);
1264                 force_section = 0;
1265         }
1266 }