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, /* no cstring section */
  73                         NULL,
  74                         NULL
  75                 },
  76                 { /* GAS_FLAVOUR_MINGW */
  77                         ".section\t.text",
  78                         ".section\t.data",
  79                         ".section .rdata,\"dr\"",
  80                         ".section\t.bss",
  81                         ".section\t.tbss,\"awT\",@nobits",
  82                         ".section\t.ctors,\"aw\",@progbits",
  83                         NULL,
  84                         NULL,
  85                         NULL
  86                 },
  87                 { /* GAS_FLAVOUR_YASM */
  88                         ".section\t.text",
  89                         ".section\t.data",
  90                         ".section\t.rodata",
  91                         ".section\t.bss",
  92                         ".section\t.tbss,\"awT\",@nobits",
  93                         ".section\t.ctors,\"aw\",@progbits",
  94                         NULL,
  95                         NULL,
  96                         NULL
  97                 },
  98                 { /* GAS_FLAVOUR_MACH_O */
  99                         ".text",
 100                         ".data",
 101                         ".const",
 102                         ".data",
 103                         NULL,             /* TLS is not supported on Mach-O */
 104                         ".mod_init_func",
 105                         ".cstring",
 106                         ".section\t__IMPORT,__jump_table,symbol_stubs,self_modifying_code+pure_instructions,5",
 107                         ".section\t__IMPORT,__pointers,non_lazy_symbol_pointers"
 108                 }
 109         };
 110
 111         assert((int) be_gas_flavour >= 0 && be_gas_flavour <= GAS_FLAVOUR_LAST);
 112         assert((int) section >= 0 && section <= GAS_SECTION_LAST);
 113         return text[be_gas_flavour][section];
 114 }
 115
 116 void be_gas_emit_switch_section(be_gas_section_t section) {
 117         if(current_section == section)
 118                 return;
 119
 120         be_emit_char('\t');
 121         be_emit_string(get_section_name(section));
 122         be_emit_char('\n');
 123         be_emit_write_line();
 124         current_section = section;
 125 }
 126
 127 void be_gas_emit_function_prolog(ir_entity *entity, unsigned alignment)
 128 {
 129         const char *name = get_entity_ld_name(entity);
 130         const char *fill_byte = "";
 131         unsigned maximum_skip;
 132
 133         be_gas_emit_switch_section(GAS_SECTION_TEXT);
 134
 135         /* write the begin line (used by scripts processing the assembler... */
 136         be_emit_write_line();
 137         be_emit_cstring("# -- Begin  ");
 138         be_emit_string(name);
 139         be_emit_char('\n');
 140         be_emit_write_line();
 141
 142         /* gcc fills space between function with 0x90, no idea if this is needed */
 143         if (be_gas_flavour == GAS_FLAVOUR_MACH_O) {
 144                 fill_byte = "0x90";
 145         }
 146
 147         if (alignment > 0) {
 148                 maximum_skip = (1 << alignment) - 1;
 149                 be_emit_cstring("\t.p2align ");
 150                 be_emit_irprintf("%u,%s,%u\n", alignment, fill_byte, maximum_skip);
 151                 be_emit_write_line();
 152         }
 153         if (get_entity_visibility(entity) == visibility_external_visible) {
 154                 be_emit_cstring(".globl ");
 155                 be_emit_string(name);
 156                 be_emit_char('\n');
 157                 be_emit_write_line();
 158         }
 159
 160         switch (be_gas_flavour) {
 161         case GAS_FLAVOUR_ELF:
 162                 be_emit_cstring("\t.type\t");
 163                 be_emit_string(name);
 164                 be_emit_cstring(", @function\n");
 165                 be_emit_write_line();
 166                 break;
 167         case GAS_FLAVOUR_MINGW:
 168                 be_emit_cstring("\t.def\t");
 169                 be_emit_string(name);
 170                 be_emit_cstring(";\t.scl\t2;\t.type\t32;\t.endef\n");
 171                 be_emit_write_line();
 172                 break;
 173         case GAS_FLAVOUR_MACH_O:
 174         case GAS_FLAVOUR_YASM:
 175                 break;
 176         }
 177         be_emit_string(name);
 178         be_emit_cstring(":\n");
 179         be_emit_write_line();
 180 }
 181
 182 void be_gas_emit_function_epilog(ir_entity *entity)
 183 {
 184         const char *name = get_entity_ld_name(entity);
 185
 186         if (be_gas_flavour == GAS_FLAVOUR_ELF) {
 187                 be_emit_cstring("\t.size\t");
 188                 be_emit_string(name);
 189                 be_emit_cstring(", .-");
 190                 be_emit_string(name);
 191                 be_emit_char('\n');
 192                 be_emit_write_line();
 193         }
 194
 195         be_emit_cstring("# -- End  ");
 196         be_emit_string(name);
 197         be_emit_char('\n');
 198         be_emit_write_line();
 199 }
 200
 201 /**
 202  * An environment containing all needed dumper data.
 203  * Currently we create the file completely in memory first, then
 204  * write it to the disk. This is an artifact from the old C-generating backend
 205  * and even there NOT needed. So we might change it in the future.
 206  */
 207 typedef struct _be_gas_decl_env {
 208         const be_main_env_t *main_env; /**< The main backend environment, used for it's debug handle. */
 209         be_gas_section_t     section;
 210         waitq               *worklist;           /**< A worklist we use to place not yet handled entities on. */
 211 } be_gas_decl_env_t;
 212
 213 /************************************************************************/
 214
 215 /**
 216  * Output a tarval.
 217  *
 218  * @param tv     the tarval
 219  * @param bytes  the width of the tarvals value in bytes
 220  */
 221 static void dump_arith_tarval(tarval *tv, int bytes)
 222 {
 223         switch (bytes) {
 224         case 1:
 225                 be_emit_irprintf("0x%02x", get_tarval_sub_bits(tv, 0));
 226                 return;
 227
 228         case 2:
 229                 be_emit_irprintf("0x%02x%02x", get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 230                 return;
 231
 232         case 4:
 233                 be_emit_irprintf("0x%02x%02x%02x%02x",
 234                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 235                 return;
 236
 237         case 8:
 238                 be_emit_irprintf("0x%02x%02x%02x%02x%02x%02x%02x%02x",
 239                         get_tarval_sub_bits(tv, 7), get_tarval_sub_bits(tv, 6), get_tarval_sub_bits(tv, 5), get_tarval_sub_bits(tv, 4),
 240                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 241                 return;
 242
 243         case 12:
 244                 be_emit_irprintf("0x%02x%02x%02x%02x%02x%02x%02x%02x"
 245                                    "%02x%02x%02x%02x", get_tarval_sub_bits(tv, 11),
 246                                 get_tarval_sub_bits(tv, 10), get_tarval_sub_bits(tv, 9),
 247                                 get_tarval_sub_bits(tv, 8), get_tarval_sub_bits(tv, 7),
 248                                 get_tarval_sub_bits(tv, 6), get_tarval_sub_bits(tv, 5),
 249                                 get_tarval_sub_bits(tv, 4), get_tarval_sub_bits(tv, 3),
 250                                 get_tarval_sub_bits(tv, 2), get_tarval_sub_bits(tv, 1),
 251                                 get_tarval_sub_bits(tv, 0));
 252                 return;
 253
 254         case 16:
 255                 be_emit_irprintf("0x%02x%02x%02x%02x%02x%02x%02x%02x"
 256                                                "%02x%02x%02x%02x%02x%02x%02x%02x",
 257                         get_tarval_sub_bits(tv, 15), get_tarval_sub_bits(tv, 16),
 258                         get_tarval_sub_bits(tv, 13), get_tarval_sub_bits(tv, 12),
 259                         get_tarval_sub_bits(tv, 11), get_tarval_sub_bits(tv, 10),
 260                         get_tarval_sub_bits(tv, 9), get_tarval_sub_bits(tv, 8),
 261                         get_tarval_sub_bits(tv, 7), get_tarval_sub_bits(tv, 6),
 262                         get_tarval_sub_bits(tv, 5), get_tarval_sub_bits(tv, 4),
 263                         get_tarval_sub_bits(tv, 3), get_tarval_sub_bits(tv, 2),
 264                         get_tarval_sub_bits(tv, 1), get_tarval_sub_bits(tv, 0));
 265                 return;
 266         }
 267
 268         panic("Can't dump a tarval with %d bytes\n", bytes);
 269 }
 270
 271 /**
 272  * Return the label prefix for labeled blocks.
 273  */
 274 const char *be_gas_label_prefix(void) {
 275         return ".LG";
 276 }
 277
 278 /**
 279  * Dump a label.
 280  */
 281 static void dump_label(ir_label_t label) {
 282         be_emit_irprintf("%s%ld", be_gas_label_prefix(), label);
 283 }
 284
 285 /**
 286  * Return the tarval of an atomic initializer.
 287  *
 288  * @param init  a node representing the initializer (on the const code irg)
 289  *
 290  * @return the tarval
 291  */
 292 static tarval *get_atomic_init_tv(ir_node *init)
 293 {
 294         for (;;) {
 295                 ir_mode *mode = get_irn_mode(init);
 296
 297                 switch (get_irn_opcode(init)) {
 298
 299                 case iro_Cast:
 300                         init = get_Cast_op(init);
 301                         continue;
 302
 303                 case iro_Conv:
 304                         init = get_Conv_op(init);
 305                         continue;
 306
 307                 case iro_Const:
 308                         return get_Const_tarval(init);
 309
 310                 case iro_SymConst:
 311                         switch (get_SymConst_kind(init)) {
 312                         case symconst_type_size:
 313                                 return new_tarval_from_long(get_type_size_bytes(get_SymConst_type(init)), mode);
 314
 315                         case symconst_type_align:
 316                                 return new_tarval_from_long(get_type_alignment_bytes(get_SymConst_type(init)), mode);
 317
 318                         case symconst_ofs_ent:
 319                                 return new_tarval_from_long(get_entity_offset(get_SymConst_entity(init)), mode);
 320
 321                         case symconst_enum_const:
 322                                 return get_enumeration_value(get_SymConst_enum(init));
 323
 324                         case symconst_label:
 325                                 return NULL;
 326
 327                         default:
 328                                 return NULL;
 329                         }
 330
 331                 default:
 332                         return NULL;
 333                 }
 334         }
 335 }
 336
 337 /**
 338  * Dump an atomic value.
 339  *
 340  * @param env   the gas output environment
 341  * @param init  a node representing the atomic value (on the const code irg)
 342  */
 343 static void do_dump_atomic_init(be_gas_decl_env_t *env, ir_node *init)
 344 {
 345         ir_mode *mode = get_irn_mode(init);
 346         int bytes     = get_mode_size_bytes(mode);
 347         tarval *tv;
 348         ir_label_t label;
 349         ir_entity *ent;
 350
 351         init = skip_Id(init);
 352
 353         switch (get_irn_opcode(init)) {
 354         case iro_Cast:
 355                 do_dump_atomic_init(env, get_Cast_op(init));
 356                 return;
 357
 358         case iro_Conv:
 359                 do_dump_atomic_init(env, get_Conv_op(init));
 360                 return;
 361
 362         case iro_Const:
 363                 tv = get_Const_tarval(init);
 364
 365                 /* it's a arithmetic value */
 366                 dump_arith_tarval(tv, bytes);
 367                 return;
 368
 369         case iro_SymConst:
 370                 switch (get_SymConst_kind(init)) {
 371                 case symconst_addr_name:
 372                         be_emit_ident(get_SymConst_name(init));
 373                         break;
 374
 375                 case symconst_addr_ent:
 376                         ent = get_SymConst_entity(init);
 377                         if(!is_entity_backend_marked(ent)) {
 378                                 waitq_put(env->worklist, ent);
 379                                 set_entity_backend_marked(ent, 1);
 380                         }
 381                         be_emit_ident(get_entity_ld_ident(ent));
 382                         break;
 383
 384                 case symconst_ofs_ent:
 385                         ent = get_SymConst_entity(init);
 386 #if 0       /* not needed, is it? */
 387                         if(!is_entity_backend_marked(ent)) {
 388                                 waitq_put(env->worklist, ent);
 389                                 set_entity_backend_marked(ent, 1);
 390                         }
 391 #endif
 392                         be_emit_irprintf("%d", get_entity_offset(ent));
 393                         break;
 394
 395                 case symconst_type_size:
 396                         be_emit_irprintf("%u", get_type_size_bytes(get_SymConst_type(init)));
 397                         break;
 398
 399                 case symconst_type_align:
 400                         be_emit_irprintf("%u", get_type_alignment_bytes(get_SymConst_type(init)));
 401                         break;
 402
 403                 case symconst_enum_const:
 404                         tv = get_enumeration_value(get_SymConst_enum(init));
 405                         dump_arith_tarval(tv, bytes);
 406                         break;
 407
 408                 case symconst_label:
 409                         label = get_SymConst_label(init);
 410                         dump_label(label);
 411                         break;
 412
 413                 default:
 414                         assert(!"dump_atomic_init(): don't know how to init from this SymConst");
 415                 }
 416                 return;
 417
 418                 case iro_Add:
 419                         if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 420                                 panic("Constant must be int or pointer for '+' to work");
 421                         }
 422                         do_dump_atomic_init(env, get_Add_left(init));
 423                         be_emit_cstring(" + ");
 424                         do_dump_atomic_init(env, get_Add_right(init));
 425                         return;
 426
 427                 case iro_Sub:
 428                         if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 429                                 panic("Constant must be int or pointer for '-' to work");
 430                         }
 431                         do_dump_atomic_init(env, get_Sub_left(init));
 432                         be_emit_cstring(" - ");
 433                         do_dump_atomic_init(env, get_Sub_right(init));
 434                         return;
 435
 436                 case iro_Mul:
 437                         if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 438                                 panic("Constant must be int or pointer for '*' to work");
 439                         }
 440                         do_dump_atomic_init(env, get_Mul_left(init));
 441                         be_emit_cstring(" * ");
 442                         do_dump_atomic_init(env, get_Mul_right(init));
 443                         return;
 444
 445                 default:
 446                         assert(0 && "dump_atomic_init(): unknown IR-node");
 447         }
 448 }
 449
 450 /**
 451  * Dumps the type for given size (.byte, .long, ...)
 452  *
 453  * @param size  the size in bytes
 454  */
 455 static void dump_size_type(size_t size) {
 456         switch (size) {
 457         case 1:
 458                 be_emit_cstring("\t.byte\t");
 459                 break;
 460
 461         case 2:
 462                 be_emit_cstring("\t.word\t");
 463                 break;
 464
 465         case 4:
 466                 be_emit_cstring("\t.long\t");
 467                 break;
 468
 469         case 8:
 470                 be_emit_cstring("\t.quad\t");
 471                 break;
 472
 473         case 10:
 474         case 12:
 475                 /* handled in arith */
 476                 break;
 477
 478         case 16:
 479                 be_emit_cstring("\t.octa\t");
 480                 break;
 481
 482         default:
 483                 panic("Try to dump a type with %u bytes\n", (unsigned) size);
 484         }
 485 }
 486
 487 /**
 488  * Emit an atomic value.
 489  *
 490  * @param env   the gas output environment
 491  * @param init  a node representing the atomic value (on the const code irg)
 492  */
 493 static void dump_atomic_init(be_gas_decl_env_t *env, ir_node *init)
 494 {
 495         ir_mode *mode = get_irn_mode(init);
 496         int bytes     = get_mode_size_bytes(mode);
 497
 498         dump_size_type(bytes);
 499         do_dump_atomic_init(env, init);
 500         be_emit_char('\n');
 501         be_emit_write_line();
 502 }
 503
 504 /************************************************************************/
 505 /* Routines to dump global variables                                    */
 506 /************************************************************************/
 507
 508 static int initializer_is_string_const(const ir_initializer_t *initializer)
 509 {
 510         size_t i, len;
 511         int found_printable = 0;
 512
 513         if(initializer->kind != IR_INITIALIZER_COMPOUND)
 514                 return 0;
 515
 516         len = initializer->compound.n_initializers;
 517         if (len < 1)
 518                 return 0;
 519         for(i = 0; i < len; ++i) {
 520                 int               c;
 521                 tarval           *tv;
 522                 ir_mode          *mode;
 523                 ir_initializer_t *sub_initializer
 524                         = initializer->compound.initializers[i];
 525
 526                 if(sub_initializer->kind != IR_INITIALIZER_TARVAL)
 527                         return 0;
 528
 529                 tv   = sub_initializer->tarval.value;
 530                 mode = get_tarval_mode(tv);
 531
 532                 if (!mode_is_int(mode)
 533                                 || get_mode_size_bits(mode) != get_mode_size_bits(mode_Bs))
 534                         return 0;
 535
 536                 c = get_tarval_long(tv);
 537                 if (isgraph(c) || isspace(c))
 538                         found_printable = 1;
 539                 else if(c != 0)
 540                         return 0;
 541
 542                 if (i == len - 1 && c != '\0')
 543                         return 0;
 544         }
 545
 546         return found_printable;
 547 }
 548
 549 /**
 550  * Determine if an entity is a string constant
 551  * @param ent The entity
 552  * @return 1 if it is a string constant, 0 otherwise
 553  */
 554 static int ent_is_string_const(ir_entity *ent)
 555 {
 556         ir_type *type, *element_type;
 557         ir_mode *mode;
 558         int i, c, n;
 559         int found_printable = 0;
 560
 561         type = get_entity_type(ent);
 562
 563         /* if it's an array */
 564         if (!is_Array_type(type))
 565                 return 0;
 566
 567         element_type = get_array_element_type(type);
 568
 569         /* and the array's element type is primitive */
 570         if (!is_Primitive_type(element_type))
 571                 return 0;
 572
 573         /* and the mode of the element type is an int of
 574          * the same size as the byte mode */
 575         mode = get_type_mode(element_type);
 576         if (!mode_is_int(mode)
 577                 || get_mode_size_bits(mode) != get_mode_size_bits(mode_Bs))
 578                 return 0;
 579
 580         if(ent->has_initializer) {
 581                 /* TODO */
 582                 return 0;
 583         } else {
 584                 /* if it contains only printable chars and a 0 at the end */
 585                 n = get_compound_ent_n_values(ent);
 586                 for (i = 0; i < n; ++i) {
 587                         ir_node *irn = get_compound_ent_value(ent, i);
 588                         if (! is_Const(irn))
 589                                 return 0;
 590
 591                         c = (int) get_tarval_long(get_Const_tarval(irn));
 592
 593                         if (isgraph(c) || isspace(c))
 594                                 found_printable = 1;
 595                         else if(c != 0)
 596                                 return 0;
 597
 598                         if (i == n - 1 && c != '\0')
 599                                 return 0;
 600                 }
 601         }
 602
 603         /* then we can emit it as a string constant */
 604         return found_printable;
 605 }
 606
 607 /**
 608  * Dump a string constant.
 609  * No checks are made!!
 610  *
 611  * @param ent  The entity to dump.
 612  */
 613 static void dump_string_cst(ir_entity *ent)
 614 {
 615         int      i, len;
 616         ir_type *type;
 617         int      type_size;
 618         int      remaining_space;
 619
 620         len = get_compound_ent_n_values(ent);
 621         if (be_gas_flavour == GAS_FLAVOUR_MACH_O) {
 622                 be_emit_cstring("\t.ascii \"");
 623         } else {
 624                 be_emit_cstring("\t.string \"");
 625                 len -= 1;
 626         }
 627
 628         for (i = 0; i < len; ++i) {
 629                 ir_node *irn;
 630                 int c;
 631
 632                 irn = get_compound_ent_value(ent, i);
 633                 c = (int) get_tarval_long(get_Const_tarval(irn));
 634
 635                 switch (c) {
 636                 case '"' : be_emit_cstring("\\\""); break;
 637                 case '\n': be_emit_cstring("\\n"); break;
 638                 case '\r': be_emit_cstring("\\r"); break;
 639                 case '\t': be_emit_cstring("\\t"); break;
 640                 case '\\': be_emit_cstring("\\\\"); break;
 641                 default  :
 642                         if (isprint(c))
 643                                 be_emit_char(c);
 644                         else
 645                                 be_emit_irprintf("\\%o", c);
 646                         break;
 647                 }
 648         }
 649         be_emit_cstring("\"\n");
 650         be_emit_write_line();
 651
 652         type            = get_entity_type(ent);
 653         type_size       = get_type_size_bytes(type);
 654         remaining_space = type_size - len;
 655         assert(remaining_space >= 0);
 656         if(remaining_space > 0) {
 657                 be_emit_irprintf("\t.skip\t%d\n", remaining_space);
 658         }
 659 }
 660
 661 static void dump_string_initializer(const ir_initializer_t *initializer)
 662 {
 663         size_t i, len;
 664
 665         len = initializer->compound.n_initializers;
 666         if(be_gas_flavour == GAS_FLAVOUR_MACH_O) {
 667                 be_emit_cstring("\t.ascii \"");
 668         } else {
 669                 be_emit_cstring("\t.string \"");
 670                 len -= 1;
 671         }
 672
 673         for(i = 0; i < len; ++i) {
 674                 const ir_initializer_t *sub_initializer
 675                         = get_initializer_compound_value(initializer, i);
 676
 677                 tarval *tv = get_initializer_tarval_value(sub_initializer);
 678                 int     c  = get_tarval_long(tv);
 679
 680                 switch (c) {
 681                 case '"' : be_emit_cstring("\\\""); break;
 682                 case '\n': be_emit_cstring("\\n"); break;
 683                 case '\r': be_emit_cstring("\\r"); break;
 684                 case '\t': be_emit_cstring("\\t"); break;
 685                 case '\\': be_emit_cstring("\\\\"); break;
 686                 default  :
 687                         if (isprint(c))
 688                                 be_emit_char(c);
 689                         else
 690                                 be_emit_irprintf("\\%o", c);
 691                         break;
 692                 }
 693         }
 694         be_emit_cstring("\"\n");
 695         be_emit_write_line();
 696 }
 697
 698 enum normal_or_bitfield_kind {
 699         NORMAL = 0,
 700         TARVAL,
 701         BITFIELD
 702 };
 703
 704 typedef struct {
 705         enum normal_or_bitfield_kind kind;
 706         union {
 707                 ir_node       *value;
 708                 tarval        *tarval;
 709                 unsigned char  bf_val;
 710         } v;
 711 } normal_or_bitfield;
 712
 713 static int is_type_variable_size(ir_type *type)
 714 {
 715         (void) type;
 716         /* TODO */
 717         return 0;
 718 }
 719
 720 static size_t get_initializer_size(const ir_initializer_t *initializer,
 721                                    ir_type *type)
 722 {
 723         switch(get_initializer_kind(initializer)) {
 724         case IR_INITIALIZER_TARVAL: {
 725                 assert(get_tarval_mode(get_initializer_tarval_value(initializer)) == get_type_mode(type));
 726                 return get_type_size_bytes(type);
 727         }
 728         case IR_INITIALIZER_CONST:
 729         case IR_INITIALIZER_NULL:
 730                 return get_type_size_bytes(type);
 731         case IR_INITIALIZER_COMPOUND: {
 732                 if(!is_type_variable_size(type)) {
 733                         return get_type_size_bytes(type);
 734                 } else {
 735                         unsigned n_entries
 736                                 = get_initializer_compound_n_entries(initializer);
 737                         unsigned i;
 738                         unsigned initializer_size = get_type_size_bytes(type);
 739                         for(i = 0; i < n_entries; ++i) {
 740                                 ir_entity *entity = get_compound_member(type, i);
 741                                 ir_type   *type   = get_entity_type(entity);
 742
 743                                 const ir_initializer_t *sub_initializer
 744                                         = get_initializer_compound_value(initializer, i);
 745
 746                                 unsigned offset = get_entity_offset(entity);
 747                                 unsigned size   = get_initializer_size(sub_initializer, type);
 748
 749                                 if(offset + size > initializer_size) {
 750                                         initializer_size = offset + size;
 751                                 }
 752                         }
 753                         return initializer_size;
 754                 }
 755         }
 756         }
 757
 758         panic("found invalid initializer");
 759 }
 760
 761 #ifndef NDEBUG
 762 static normal_or_bitfield *glob_vals;
 763 static size_t              max_vals;
 764 #endif
 765
 766 static void dump_bitfield(normal_or_bitfield *vals, size_t offset_bits,
 767                           const ir_initializer_t *initializer, ir_type *type)
 768 {
 769         unsigned char  last_bits = 0;
 770         ir_mode       *mode      = get_type_mode(type);
 771         tarval        *tv        = NULL;
 772         unsigned char  curr_bits;
 773         int            value_len;
 774         int            j;
 775
 776         switch(get_initializer_kind(initializer)) {
 777         case IR_INITIALIZER_NULL:
 778                 return;
 779         case IR_INITIALIZER_TARVAL:
 780                 tv = get_initializer_tarval_value(initializer);
 781                 break;
 782         case IR_INITIALIZER_CONST: {
 783                 ir_node *node = get_initializer_const_value(initializer);
 784                 if(!is_Const(node)) {
 785                         panic("bitfield initializer not a Const node");
 786                 }
 787                 tv = get_Const_tarval(node);
 788                 break;
 789         }
 790         case IR_INITIALIZER_COMPOUND:
 791                 panic("bitfield initializer is compound");
 792         }
 793         if (tv == NULL) {
 794                 panic("Couldn't get numeric value for bitfield initializer\n");
 795         }
 796
 797         /* normalize offset */
 798         vals        += offset_bits >> 3;
 799         offset_bits &= 7;
 800         value_len    = get_mode_size_bits(mode);
 801
 802         /* combine bits with existing bits */
 803         for (j = 0; value_len + (int) offset_bits > 0; ++j) {
 804                 assert((size_t) (vals - glob_vals) + j < max_vals);
 805                 assert(vals[j].kind == BITFIELD ||
 806                                 (vals[j].kind == NORMAL && vals[j].v.value == NULL));
 807                 vals[j].kind = BITFIELD;
 808                 curr_bits    = get_tarval_sub_bits(tv, j);
 809                 vals[j].v.bf_val
 810                         |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
 811                 value_len -= 8;
 812                 last_bits = curr_bits;
 813         }
 814 }
 815
 816 static void dump_ir_initializer(normal_or_bitfield *vals,
 817                                 const ir_initializer_t *initializer,
 818                                 ir_type *type)
 819 {
 820         assert((size_t) (vals - glob_vals) < max_vals);
 821
 822         switch(get_initializer_kind(initializer)) {
 823         case IR_INITIALIZER_NULL:
 824                 return;
 825         case IR_INITIALIZER_TARVAL: {
 826                 size_t i;
 827
 828                 assert(vals->kind != BITFIELD);
 829                 vals->kind     = TARVAL;
 830                 vals->v.tarval = get_initializer_tarval_value(initializer);
 831                 assert(get_type_mode(type) == get_tarval_mode(vals->v.tarval));
 832                 for(i = 1; i < get_type_size_bytes(type); ++i) {
 833                         vals[i].kind    = NORMAL;
 834                         vals[i].v.value = NULL;
 835                 }
 836                 return;
 837         }
 838         case IR_INITIALIZER_CONST: {
 839                 size_t i;
 840
 841                 assert(vals->kind != BITFIELD);
 842                 vals->kind    = NORMAL;
 843                 vals->v.value = get_initializer_const_value(initializer);
 844                 for(i = 1; i < get_type_size_bytes(type); ++i) {
 845                         vals[i].kind    = NORMAL;
 846                         vals[i].v.value = NULL;
 847                 }
 848                 return;
 849         }
 850         case IR_INITIALIZER_COMPOUND: {
 851                 size_t i = 0;
 852                 size_t n = get_initializer_compound_n_entries(initializer);
 853
 854                 if(is_Array_type(type)) {
 855                         ir_type *element_type = get_array_element_type(type);
 856                         size_t   skip         = get_type_size_bytes(element_type);
 857                         size_t   alignment    = get_type_alignment_bytes(element_type);
 858                         size_t   misalign     = skip % alignment;
 859                         if(misalign != 0) {
 860                                 skip += alignment - misalign;
 861                         }
 862
 863                         for(i = 0; i < n; ++i) {
 864                                 ir_initializer_t *sub_initializer
 865                                         = get_initializer_compound_value(initializer, i);
 866
 867                                 dump_ir_initializer(vals, sub_initializer, element_type);
 868
 869                                 vals += skip;
 870                         }
 871                 } else {
 872                         size_t n_members, i;
 873                         assert(is_compound_type(type));
 874                         n_members = get_compound_n_members(type);
 875                         for(i = 0; i < n_members; ++i) {
 876                                 ir_entity        *member    = get_compound_member(type, i);
 877                                 size_t            offset    = get_entity_offset(member);
 878                                 ir_type          *subtype   = get_entity_type(member);
 879                                 ir_mode          *mode      = get_type_mode(subtype);
 880                                 ir_initializer_t *sub_initializer;
 881
 882                                 assert(i < get_initializer_compound_n_entries(initializer));
 883                                 sub_initializer
 884                                         = get_initializer_compound_value(initializer, i);
 885
 886                                 if(mode != NULL) {
 887                                         size_t offset_bits
 888                                                 = get_entity_offset_bits_remainder(member);
 889                                         size_t value_len   = get_mode_size_bits(mode);
 890
 891                                         if(offset_bits != 0 ||
 892                                                 (value_len != 8 && value_len != 16 && value_len != 32
 893                                                  && value_len != 64)) {
 894                                                 dump_bitfield(&vals[offset], offset_bits,
 895                                                               sub_initializer, subtype);
 896                                                 continue;
 897                                         }
 898                                 }
 899
 900                                 dump_ir_initializer(&vals[offset], sub_initializer, subtype);
 901                         }
 902                 }
 903
 904                 return;
 905         }
 906         }
 907         panic("invalid ir_initializer kind found");
 908 }
 909
 910 static void dump_initializer(be_gas_decl_env_t *env, ir_entity *entity)
 911 {
 912         const ir_initializer_t *initializer = entity->attr.initializer;
 913         ir_type                *type;
 914         normal_or_bitfield     *vals;
 915         size_t                  size;
 916         size_t                  k;
 917
 918         if(initializer_is_string_const(initializer)) {
 919                 dump_string_initializer(initializer);
 920                 return;
 921         }
 922
 923         type = get_entity_type(entity);
 924         size = get_initializer_size(initializer, type);
 925
 926         if (size == 0)
 927                 return;
 928
 929         /*
 930          * In the worst case, every initializer allocates one byte.
 931          * Moreover, initializer might be big, do not allocate on stack.
 932          */
 933         vals = xcalloc(size, sizeof(vals[0]));
 934
 935 #ifndef NDEBUG
 936         glob_vals = vals;
 937         max_vals  = size;
 938 #endif
 939
 940         dump_ir_initializer(vals, initializer, type);
 941
 942         /* now write values sorted */
 943         for (k = 0; k < size; ) {
 944                 int space     = 0;
 945                 int elem_size = 1;
 946                 if (vals[k].kind == NORMAL) {
 947                         if(vals[k].v.value != NULL) {
 948                                 dump_atomic_init(env, vals[k].v.value);
 949                                 elem_size = get_mode_size_bytes(get_irn_mode(vals[k].v.value));
 950                         } else {
 951                                 elem_size = 0;
 952                         }
 953                 } else if(vals[k].kind == TARVAL) {
 954                         tarval *tv   = vals[k].v.tarval;
 955                         size_t  size = get_mode_size_bytes(get_tarval_mode(tv));
 956
 957                         assert(tv != NULL);
 958
 959                         elem_size = size;
 960                         dump_size_type(size);
 961                         dump_arith_tarval(tv, size);
 962                         be_emit_char('\n');
 963                         be_emit_write_line();
 964                 } else {
 965                         assert(vals[k].kind == BITFIELD);
 966                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
 967                         be_emit_write_line();
 968                 }
 969
 970                 k += elem_size;
 971                 while (k < size && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
 972                         ++space;
 973                         ++k;
 974                 }
 975
 976                 /* a gap */
 977                 if (space > 0) {
 978                         be_emit_irprintf("\t.skip\t%d\n", space);
 979                         be_emit_write_line();
 980                 }
 981         }
 982         xfree(vals);
 983 }
 984
 985 /**
 986  * Dump an initializer for a compound entity.
 987  */
 988 static void dump_compound_init(be_gas_decl_env_t *env, ir_entity *ent)
 989 {
 990         normal_or_bitfield *vals;
 991         int i, j, n;
 992         unsigned k, last_ofs;
 993
 994         if(ent->has_initializer) {
 995                 dump_initializer(env, ent);
 996                 return;
 997         }
 998
 999         n = get_compound_ent_n_values(ent);
1000
1001         /* Find the initializer size. Sorrily gcc support a nasty feature:
1002            The last field of a compound may be a flexible array. This allows
1003            initializers bigger than the type size. */
1004         last_ofs = get_type_size_bytes(get_entity_type(ent));
1005         for (i = 0; i < n; ++i) {
1006                 unsigned offset         = get_compound_ent_value_offset_bytes(ent, i);
1007                 unsigned bits_remainder = get_compound_ent_value_offset_bit_remainder(ent, i);
1008                 ir_node  *value         = get_compound_ent_value(ent, i);
1009                 unsigned value_len      = get_mode_size_bits(get_irn_mode(value));
1010
1011                 offset += (value_len + bits_remainder + 7) >> 3;
1012
1013                 if (offset > last_ofs) {
1014                         last_ofs = offset;
1015                 }
1016         }
1017
1018         /*
1019          * In the worst case, every initializer allocates one byte.
1020          * Moreover, initializer might be big, do not allocate on stack.
1021          */
1022         vals = xcalloc(last_ofs, sizeof(vals[0]));
1023
1024         /* collect the values and store them at the offsets */
1025         for (i = 0; i < n; ++i) {
1026                 unsigned offset      = get_compound_ent_value_offset_bytes(ent, i);
1027                 int      offset_bits = get_compound_ent_value_offset_bit_remainder(ent, i);
1028                 ir_node  *value      = get_compound_ent_value(ent, i);
1029                 int      value_len   = get_mode_size_bits(get_irn_mode(value));
1030
1031                 assert(offset_bits >= 0);
1032
1033                 if (offset_bits != 0 ||
1034                         (value_len != 8 && value_len != 16 && value_len != 32 && value_len != 64)) {
1035                         tarval *tv = get_atomic_init_tv(value);
1036                         unsigned char curr_bits, last_bits = 0;
1037                         if (tv == NULL) {
1038                                 panic("Couldn't get numeric value for bitfield initializer '%s'\n",
1039                                       get_entity_ld_name(ent));
1040                         }
1041                         /* normalize offset */
1042                         offset += offset_bits >> 3;
1043                         offset_bits &= 7;
1044
1045                         for (j = 0; value_len + offset_bits > 0; ++j) {
1046                                 assert(offset + j < last_ofs);
1047                                 assert(vals[offset + j].kind == BITFIELD || vals[offset + j].v.value == NULL);
1048                                 vals[offset + j].kind = BITFIELD;
1049                                 curr_bits = get_tarval_sub_bits(tv, j);
1050                                 vals[offset + j].v.bf_val |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
1051                                 value_len -= 8;
1052                                 last_bits = curr_bits;
1053                         }
1054                 } else {
1055                         int i;
1056
1057                         assert(offset < last_ofs);
1058                         assert(vals[offset].kind == NORMAL);
1059                         for (i = 1; i < value_len / 8; ++i) {
1060                                 assert(vals[offset + i].v.value == NULL);
1061                         }
1062                         vals[offset].v.value = value;
1063                 }
1064         }
1065
1066         /* now write them sorted */
1067         for (k = 0; k < last_ofs; ) {
1068                 int space = 0, skip = 0;
1069                 if (vals[k].kind == NORMAL) {
1070                         if(vals[k].v.value != NULL) {
1071                                 dump_atomic_init(env, vals[k].v.value);
1072                                 skip = get_mode_size_bytes(get_irn_mode(vals[k].v.value)) - 1;
1073                         } else {
1074                                 space = 1;
1075                         }
1076                 } else {
1077                         assert(vals[k].kind == BITFIELD);
1078                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
1079                 }
1080
1081                 ++k;
1082                 while (k < last_ofs && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
1083                         ++space;
1084                         ++k;
1085                 }
1086                 space -= skip;
1087                 assert(space >= 0);
1088
1089                 /* a gap */
1090                 if (space > 0) {
1091                         be_emit_irprintf("\t.skip\t%d\n", space);
1092                         be_emit_write_line();
1093                 }
1094         }
1095         xfree(vals);
1096 }
1097
1098 static void emit_align(unsigned alignment)
1099 {
1100         if (!is_po2(alignment))
1101                 panic("alignment not a power of 2");
1102
1103         be_emit_irprintf(".p2align\t%u\n", log2_floor(alignment));
1104         be_emit_write_line();
1105 }
1106
1107 /**
1108  * Dump a global entity.
1109  *
1110  * @param env           the gas output environment
1111  * @param ent           the entity to be dumped
1112  */
1113 static void dump_global(be_gas_decl_env_t *env, ir_entity *ent)
1114 {
1115         ir_type          *type           = get_entity_type(ent);
1116         ident            *ld_ident       = get_entity_ld_ident(ent);
1117         unsigned          align          = get_type_alignment_bytes(type);
1118         int               emit_as_common = 0;
1119         be_gas_section_t  section        = env->section;
1120         ir_variability    variability    = get_entity_variability(ent);
1121         ir_visibility     visibility     = get_entity_visibility(ent);
1122
1123         if (is_Method_type(type) && section != GAS_SECTION_PIC_TRAMPOLINES) {
1124                 return;
1125         }
1126
1127         if (section != (be_gas_section_t) -1) {
1128                 emit_as_common = 0;
1129         } else if (variability == variability_constant) {
1130                 /* a constant entity, put it on the rdata */
1131                 section = GAS_SECTION_RODATA;
1132                 if (be_gas_flavour == GAS_FLAVOUR_MACH_O
1133                                 && ent_is_string_const(ent)) {
1134                         section = GAS_SECTION_CSTRING;
1135                 }
1136         } else if (variability == variability_uninitialized) {
1137                 /* uninitialized entity put it in bss segment */
1138                 section = GAS_SECTION_COMMON;
1139                 if (visibility != visibility_local)
1140                         emit_as_common = 1;
1141         } else {
1142                 section = GAS_SECTION_DATA;
1143         }
1144
1145         if(!emit_as_common) {
1146                 be_gas_emit_switch_section(section);
1147         }
1148
1149         be_dbg_variable(ent);
1150
1151         /* global or not global */
1152         if (visibility == visibility_external_visible && !emit_as_common) {
1153                 be_emit_cstring(".globl\t");
1154                 be_emit_ident(ld_ident);
1155                 be_emit_char('\n');
1156                 be_emit_write_line();
1157         } else if(visibility == visibility_external_allocated) {
1158                 be_emit_cstring(".globl\t");
1159                 be_emit_ident(ld_ident);
1160                 be_emit_char('\n');
1161                 be_emit_write_line();
1162                 /* we can return now... */
1163                 return;
1164         }
1165         /* alignment */
1166         if (align > 1 && !emit_as_common && section != GAS_SECTION_PIC_TRAMPOLINES
1167                         && section != GAS_SECTION_PIC_SYMBOLS) {
1168                 emit_align(align);
1169         }
1170
1171         if (!emit_as_common) {
1172                 be_emit_ident(ld_ident);
1173                 be_emit_cstring(":\n");
1174                 be_emit_write_line();
1175         }
1176
1177         if (variability == variability_uninitialized) {
1178                 if (emit_as_common) {
1179                         switch (be_gas_flavour) {
1180                         case GAS_FLAVOUR_ELF:
1181                         case GAS_FLAVOUR_MACH_O:
1182                         case GAS_FLAVOUR_YASM:
1183                                 be_emit_irprintf("\t.comm %s,%u,%u\n",
1184                                         get_id_str(ld_ident), get_type_size_bytes(type), align);
1185                                 be_emit_write_line();
1186                                 break;
1187                         case GAS_FLAVOUR_MINGW:
1188                                 be_emit_irprintf("\t.comm %s,%u # %u\n",
1189                                         get_id_str(ld_ident), get_type_size_bytes(type), align);
1190                                 be_emit_write_line();
1191                                 break;
1192                         }
1193                 } else if (section == GAS_SECTION_PIC_TRAMPOLINES) {
1194                         if (be_gas_flavour == GAS_FLAVOUR_MACH_O) {
1195                                 be_emit_cstring("\t.indirect_symbol ");
1196                                 be_emit_ident(get_entity_ident(ent));
1197                                 be_emit_char('\n');
1198                                 be_emit_write_line();
1199                                 be_emit_cstring("\thlt ; hlt ; hlt ; hlt ; hlt\n");
1200                                 be_emit_write_line();
1201                         } else {
1202                                 panic("PIC trampolines not yet supported in this gas mode");
1203                         }
1204                 } else {
1205                         be_emit_irprintf("\t.space %u\n", get_type_size_bytes(type));
1206                         be_emit_write_line();
1207                 }
1208         } else {
1209                 if (is_atomic_entity(ent)) {
1210                         dump_atomic_init(env, get_atomic_ent_value(ent));
1211                 } else {
1212                         /* sort_compound_ent_values(ent); */
1213
1214                         switch (get_type_tpop_code(get_entity_type(ent))) {
1215                         case tpo_array:
1216                                 if (ent_is_string_const(ent))
1217                                         dump_string_cst(ent);
1218                                 else
1219                                         dump_compound_init(env, ent);
1220                                 break;
1221                         case tpo_struct:
1222                         case tpo_class:
1223                         case tpo_union:
1224                                 dump_compound_init(env, ent);
1225                                 break;
1226                         default:
1227                                 assert(0);
1228                         }
1229                 }
1230         }
1231 }
1232
1233 /**
1234  * Dumps declarations of global variables and the initialization code.
1235  *
1236  * @param gt                a global like type, either the global or the TLS one
1237  * @param env               an environment
1238  * @param only_emit_marked  if non-zero, external allocated entities that do not have
1239  *                          its visited flag set are ignored
1240  */
1241 static void be_gas_dump_globals(ir_type *gt, be_gas_decl_env_t *env,
1242                                 int only_emit_marked)
1243 {
1244         int i, n = get_compound_n_members(gt);
1245         waitq *worklist = new_waitq();
1246
1247         if (only_emit_marked) {
1248                 for (i = 0; i < n; i++) {
1249                         ir_entity *ent = get_compound_member(gt, i);
1250                         if (is_entity_backend_marked(ent) ||
1251                             get_entity_visibility(ent) != visibility_external_allocated) {
1252                                 waitq_put(worklist, ent);
1253                                 set_entity_backend_marked(ent, 1);
1254                         }
1255                 }
1256         } else {
1257                 for (i = 0; i < n; i++) {
1258                         ir_entity *ent = get_compound_member(gt, i);
1259                         set_entity_backend_marked(ent, 1);
1260                         waitq_put(worklist, ent);
1261                 }
1262         }
1263
1264         env->worklist = worklist;
1265
1266         while (!waitq_empty(worklist)) {
1267                 ir_entity *ent = waitq_get(worklist);
1268
1269                 dump_global(env, ent);
1270         }
1271
1272         del_waitq(worklist);
1273         env->worklist = NULL;
1274 }
1275
1276 /************************************************************************/
1277
1278 /* Generate all entities. */
1279 void be_gas_emit_decls(const be_main_env_t *main_env,
1280                        int only_emit_marked_entities)
1281 {
1282         be_gas_decl_env_t env;
1283         memset(&env, 0, sizeof(env));
1284
1285         env.main_env = main_env;
1286
1287         /* dump global type */
1288         env.section = (be_gas_section_t) -1;
1289         be_gas_dump_globals(get_glob_type(), &env, only_emit_marked_entities);
1290         env.section = GAS_SECTION_TLS;
1291         be_gas_dump_globals(get_tls_type(), &env, only_emit_marked_entities);
1292         env.section = GAS_SECTION_CTOR;
1293         be_gas_dump_globals(get_constructors_type(), &env,
1294                             only_emit_marked_entities);
1295         env.section = GAS_SECTION_PIC_SYMBOLS;
1296         be_gas_dump_globals(main_env->pic_symbols_type, &env,
1297                             only_emit_marked_entities);
1298
1299         if (get_compound_n_members(main_env->pic_trampolines_type) > 0) {
1300                 env.section = GAS_SECTION_PIC_TRAMPOLINES;
1301                 be_gas_dump_globals(main_env->pic_trampolines_type, &env,
1302                                     only_emit_marked_entities);
1303                 if (be_gas_flavour == GAS_FLAVOUR_MACH_O) {
1304                         be_emit_cstring("\t.subsections_via_symbols\n");
1305                         be_emit_write_line();
1306                 }
1307         }
1308 }