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