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_block_label_prefix(void) {
 275         return ".LG";
 276 }
 277
 278 /**
 279  * Return the label prefix for labeled instructions.
 280  */
 281 const char *be_gas_insn_label_prefix(void) {
 282         return ".LE";
 283 }
 284
 285 /**
 286  * Dump a label.
 287  */
 288 static void dump_label(ir_label_t label) {
 289         be_emit_irprintf("%s%u", be_gas_block_label_prefix(), label);
 290 }
 291
 292 /**
 293  * Return the tarval of an atomic initializer.
 294  *
 295  * @param init  a node representing the initializer (on the const code irg)
 296  *
 297  * @return the tarval
 298  */
 299 static tarval *get_atomic_init_tv(ir_node *init)
 300 {
 301         for (;;) {
 302                 ir_mode *mode = get_irn_mode(init);
 303
 304                 switch (get_irn_opcode(init)) {
 305
 306                 case iro_Cast:
 307                         init = get_Cast_op(init);
 308                         continue;
 309
 310                 case iro_Conv:
 311                         init = get_Conv_op(init);
 312                         continue;
 313
 314                 case iro_Const:
 315                         return get_Const_tarval(init);
 316
 317                 case iro_SymConst:
 318                         switch (get_SymConst_kind(init)) {
 319                         case symconst_type_size:
 320                                 return new_tarval_from_long(get_type_size_bytes(get_SymConst_type(init)), mode);
 321
 322                         case symconst_type_align:
 323                                 return new_tarval_from_long(get_type_alignment_bytes(get_SymConst_type(init)), mode);
 324
 325                         case symconst_ofs_ent:
 326                                 return new_tarval_from_long(get_entity_offset(get_SymConst_entity(init)), mode);
 327
 328                         case symconst_enum_const:
 329                                 return get_enumeration_value(get_SymConst_enum(init));
 330
 331                         case symconst_label:
 332                                 return NULL;
 333
 334                         default:
 335                                 return NULL;
 336                         }
 337
 338                 default:
 339                         return NULL;
 340                 }
 341         }
 342 }
 343
 344 /**
 345  * Dump an atomic value.
 346  *
 347  * @param env   the gas output environment
 348  * @param init  a node representing the atomic value (on the const code irg)
 349  */
 350 static void do_dump_atomic_init(be_gas_decl_env_t *env, ir_node *init)
 351 {
 352         ir_mode *mode = get_irn_mode(init);
 353         int bytes     = get_mode_size_bytes(mode);
 354         tarval *tv;
 355         ir_label_t label;
 356         ir_entity *ent;
 357
 358         init = skip_Id(init);
 359
 360         switch (get_irn_opcode(init)) {
 361         case iro_Cast:
 362                 do_dump_atomic_init(env, get_Cast_op(init));
 363                 return;
 364
 365         case iro_Conv:
 366                 do_dump_atomic_init(env, get_Conv_op(init));
 367                 return;
 368
 369         case iro_Const:
 370                 tv = get_Const_tarval(init);
 371
 372                 /* it's a arithmetic value */
 373                 dump_arith_tarval(tv, bytes);
 374                 return;
 375
 376         case iro_SymConst:
 377                 switch (get_SymConst_kind(init)) {
 378                 case symconst_addr_name:
 379                         be_emit_ident(get_SymConst_name(init));
 380                         break;
 381
 382                 case symconst_addr_ent:
 383                         ent = get_SymConst_entity(init);
 384                         if(!is_entity_backend_marked(ent)) {
 385                                 waitq_put(env->worklist, ent);
 386                                 set_entity_backend_marked(ent, 1);
 387                         }
 388                         be_emit_ident(get_entity_ld_ident(ent));
 389                         break;
 390
 391                 case symconst_ofs_ent:
 392                         ent = get_SymConst_entity(init);
 393 #if 0       /* not needed, is it? */
 394                         if(!is_entity_backend_marked(ent)) {
 395                                 waitq_put(env->worklist, ent);
 396                                 set_entity_backend_marked(ent, 1);
 397                         }
 398 #endif
 399                         be_emit_irprintf("%d", get_entity_offset(ent));
 400                         break;
 401
 402                 case symconst_type_size:
 403                         be_emit_irprintf("%u", get_type_size_bytes(get_SymConst_type(init)));
 404                         break;
 405
 406                 case symconst_type_align:
 407                         be_emit_irprintf("%u", get_type_alignment_bytes(get_SymConst_type(init)));
 408                         break;
 409
 410                 case symconst_enum_const:
 411                         tv = get_enumeration_value(get_SymConst_enum(init));
 412                         dump_arith_tarval(tv, bytes);
 413                         break;
 414
 415                 case symconst_label:
 416                         label = get_SymConst_label(init);
 417                         dump_label(label);
 418                         break;
 419
 420                 default:
 421                         assert(!"dump_atomic_init(): don't know how to init from this SymConst");
 422                 }
 423                 return;
 424
 425                 case iro_Add:
 426                         if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 427                                 panic("Constant must be int or pointer for '+' to work");
 428                         }
 429                         do_dump_atomic_init(env, get_Add_left(init));
 430                         be_emit_cstring(" + ");
 431                         do_dump_atomic_init(env, get_Add_right(init));
 432                         return;
 433
 434                 case iro_Sub:
 435                         if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 436                                 panic("Constant must be int or pointer for '-' to work");
 437                         }
 438                         do_dump_atomic_init(env, get_Sub_left(init));
 439                         be_emit_cstring(" - ");
 440                         do_dump_atomic_init(env, get_Sub_right(init));
 441                         return;
 442
 443                 case iro_Mul:
 444                         if (!mode_is_int(mode) && !mode_is_reference(mode)) {
 445                                 panic("Constant must be int or pointer for '*' to work");
 446                         }
 447                         do_dump_atomic_init(env, get_Mul_left(init));
 448                         be_emit_cstring(" * ");
 449                         do_dump_atomic_init(env, get_Mul_right(init));
 450                         return;
 451
 452                 default:
 453                         assert(0 && "dump_atomic_init(): unknown IR-node");
 454         }
 455 }
 456
 457 /**
 458  * Dumps the type for given size (.byte, .long, ...)
 459  *
 460  * @param size  the size in bytes
 461  */
 462 static void dump_size_type(size_t size) {
 463         switch (size) {
 464         case 1:
 465                 be_emit_cstring("\t.byte\t");
 466                 break;
 467
 468         case 2:
 469                 be_emit_cstring("\t.word\t");
 470                 break;
 471
 472         case 4:
 473                 be_emit_cstring("\t.long\t");
 474                 break;
 475
 476         case 8:
 477                 be_emit_cstring("\t.quad\t");
 478                 break;
 479
 480         case 10:
 481         case 12:
 482                 /* handled in arith */
 483                 break;
 484
 485         case 16:
 486                 be_emit_cstring("\t.octa\t");
 487                 break;
 488
 489         default:
 490                 panic("Try to dump a type with %u bytes\n", (unsigned) size);
 491         }
 492 }
 493
 494 /**
 495  * Emit an atomic value.
 496  *
 497  * @param env   the gas output environment
 498  * @param init  a node representing the atomic value (on the const code irg)
 499  */
 500 static void dump_atomic_init(be_gas_decl_env_t *env, ir_node *init)
 501 {
 502         ir_mode *mode = get_irn_mode(init);
 503         int bytes     = get_mode_size_bytes(mode);
 504
 505         dump_size_type(bytes);
 506         do_dump_atomic_init(env, init);
 507         be_emit_char('\n');
 508         be_emit_write_line();
 509 }
 510
 511 /************************************************************************/
 512 /* Routines to dump global variables                                    */
 513 /************************************************************************/
 514
 515 static int initializer_is_string_const(const ir_initializer_t *initializer)
 516 {
 517         size_t i, len;
 518         int found_printable = 0;
 519
 520         if(initializer->kind != IR_INITIALIZER_COMPOUND)
 521                 return 0;
 522
 523         len = initializer->compound.n_initializers;
 524         if (len < 1)
 525                 return 0;
 526         for(i = 0; i < len; ++i) {
 527                 int               c;
 528                 tarval           *tv;
 529                 ir_mode          *mode;
 530                 ir_initializer_t *sub_initializer
 531                         = initializer->compound.initializers[i];
 532
 533                 if(sub_initializer->kind != IR_INITIALIZER_TARVAL)
 534                         return 0;
 535
 536                 tv   = sub_initializer->tarval.value;
 537                 mode = get_tarval_mode(tv);
 538
 539                 if (!mode_is_int(mode)
 540                                 || get_mode_size_bits(mode) != get_mode_size_bits(mode_Bs))
 541                         return 0;
 542
 543                 c = get_tarval_long(tv);
 544                 if (isgraph(c) || isspace(c))
 545                         found_printable = 1;
 546                 else if(c != 0)
 547                         return 0;
 548
 549                 if (i == len - 1 && c != '\0')
 550                         return 0;
 551         }
 552
 553         return found_printable;
 554 }
 555
 556 /**
 557  * Determine if an entity is a string constant
 558  * @param ent The entity
 559  * @return 1 if it is a string constant, 0 otherwise
 560  */
 561 static int ent_is_string_const(ir_entity *ent)
 562 {
 563         ir_type *type, *element_type;
 564         ir_mode *mode;
 565         int i, c, n;
 566         int found_printable = 0;
 567
 568         type = get_entity_type(ent);
 569
 570         /* if it's an array */
 571         if (!is_Array_type(type))
 572                 return 0;
 573
 574         element_type = get_array_element_type(type);
 575
 576         /* and the array's element type is primitive */
 577         if (!is_Primitive_type(element_type))
 578                 return 0;
 579
 580         /* and the mode of the element type is an int of
 581          * the same size as the byte mode */
 582         mode = get_type_mode(element_type);
 583         if (!mode_is_int(mode)
 584                 || get_mode_size_bits(mode) != get_mode_size_bits(mode_Bs))
 585                 return 0;
 586
 587         if(ent->has_initializer) {
 588                 /* TODO */
 589                 return 0;
 590         } else {
 591                 /* if it contains only printable chars and a 0 at the end */
 592                 n = get_compound_ent_n_values(ent);
 593                 for (i = 0; i < n; ++i) {
 594                         ir_node *irn = get_compound_ent_value(ent, i);
 595                         if (! is_Const(irn))
 596                                 return 0;
 597
 598                         c = (int) get_tarval_long(get_Const_tarval(irn));
 599
 600                         if (isgraph(c) || isspace(c))
 601                                 found_printable = 1;
 602                         else if(c != 0)
 603                                 return 0;
 604
 605                         if (i == n - 1 && c != '\0')
 606                                 return 0;
 607                 }
 608         }
 609
 610         /* then we can emit it as a string constant */
 611         return found_printable;
 612 }
 613
 614 /**
 615  * Dump a string constant.
 616  * No checks are made!!
 617  *
 618  * @param ent  The entity to dump.
 619  */
 620 static void dump_string_cst(ir_entity *ent)
 621 {
 622         int      i, len;
 623         ir_type *type;
 624         int      type_size;
 625         int      remaining_space;
 626
 627         len = get_compound_ent_n_values(ent);
 628         if (be_gas_flavour == GAS_FLAVOUR_MACH_O) {
 629                 be_emit_cstring("\t.ascii \"");
 630         } else {
 631                 be_emit_cstring("\t.string \"");
 632                 len -= 1;
 633         }
 634
 635         for (i = 0; i < len; ++i) {
 636                 ir_node *irn;
 637                 int c;
 638
 639                 irn = get_compound_ent_value(ent, i);
 640                 c = (int) get_tarval_long(get_Const_tarval(irn));
 641
 642                 switch (c) {
 643                 case '"' : be_emit_cstring("\\\""); break;
 644                 case '\n': be_emit_cstring("\\n"); break;
 645                 case '\r': be_emit_cstring("\\r"); break;
 646                 case '\t': be_emit_cstring("\\t"); break;
 647                 case '\\': be_emit_cstring("\\\\"); break;
 648                 default  :
 649                         if (isprint(c))
 650                                 be_emit_char(c);
 651                         else
 652                                 be_emit_irprintf("\\%o", c);
 653                         break;
 654                 }
 655         }
 656         be_emit_cstring("\"\n");
 657         be_emit_write_line();
 658
 659         type            = get_entity_type(ent);
 660         type_size       = get_type_size_bytes(type);
 661         remaining_space = type_size - len;
 662         assert(remaining_space >= 0);
 663         if(remaining_space > 0) {
 664                 be_emit_irprintf("\t.skip\t%d\n", remaining_space);
 665         }
 666 }
 667
 668 static void dump_string_initializer(const ir_initializer_t *initializer)
 669 {
 670         size_t i, len;
 671
 672         len = initializer->compound.n_initializers;
 673         if(be_gas_flavour == GAS_FLAVOUR_MACH_O) {
 674                 be_emit_cstring("\t.ascii \"");
 675         } else {
 676                 be_emit_cstring("\t.string \"");
 677                 len -= 1;
 678         }
 679
 680         for(i = 0; i < len; ++i) {
 681                 const ir_initializer_t *sub_initializer
 682                         = get_initializer_compound_value(initializer, i);
 683
 684                 tarval *tv = get_initializer_tarval_value(sub_initializer);
 685                 int     c  = get_tarval_long(tv);
 686
 687                 switch (c) {
 688                 case '"' : be_emit_cstring("\\\""); break;
 689                 case '\n': be_emit_cstring("\\n"); break;
 690                 case '\r': be_emit_cstring("\\r"); break;
 691                 case '\t': be_emit_cstring("\\t"); break;
 692                 case '\\': be_emit_cstring("\\\\"); break;
 693                 default  :
 694                         if (isprint(c))
 695                                 be_emit_char(c);
 696                         else
 697                                 be_emit_irprintf("\\%o", c);
 698                         break;
 699                 }
 700         }
 701         be_emit_cstring("\"\n");
 702         be_emit_write_line();
 703 }
 704
 705 enum normal_or_bitfield_kind {
 706         NORMAL = 0,
 707         TARVAL,
 708         BITFIELD
 709 };
 710
 711 typedef struct {
 712         enum normal_or_bitfield_kind kind;
 713         union {
 714                 ir_node       *value;
 715                 tarval        *tarval;
 716                 unsigned char  bf_val;
 717         } v;
 718 } normal_or_bitfield;
 719
 720 static int is_type_variable_size(ir_type *type)
 721 {
 722         (void) type;
 723         /* TODO */
 724         return 0;
 725 }
 726
 727 static size_t get_initializer_size(const ir_initializer_t *initializer,
 728                                    ir_type *type)
 729 {
 730         switch(get_initializer_kind(initializer)) {
 731         case IR_INITIALIZER_TARVAL: {
 732                 assert(get_tarval_mode(get_initializer_tarval_value(initializer)) == get_type_mode(type));
 733                 return get_type_size_bytes(type);
 734         }
 735         case IR_INITIALIZER_CONST:
 736         case IR_INITIALIZER_NULL:
 737                 return get_type_size_bytes(type);
 738         case IR_INITIALIZER_COMPOUND: {
 739                 if(!is_type_variable_size(type)) {
 740                         return get_type_size_bytes(type);
 741                 } else {
 742                         unsigned n_entries
 743                                 = get_initializer_compound_n_entries(initializer);
 744                         unsigned i;
 745                         unsigned initializer_size = get_type_size_bytes(type);
 746                         for(i = 0; i < n_entries; ++i) {
 747                                 ir_entity *entity = get_compound_member(type, i);
 748                                 ir_type   *type   = get_entity_type(entity);
 749
 750                                 const ir_initializer_t *sub_initializer
 751                                         = get_initializer_compound_value(initializer, i);
 752
 753                                 unsigned offset = get_entity_offset(entity);
 754                                 unsigned size   = get_initializer_size(sub_initializer, type);
 755
 756                                 if(offset + size > initializer_size) {
 757                                         initializer_size = offset + size;
 758                                 }
 759                         }
 760                         return initializer_size;
 761                 }
 762         }
 763         }
 764
 765         panic("found invalid initializer");
 766 }
 767
 768 #ifndef NDEBUG
 769 static normal_or_bitfield *glob_vals;
 770 static size_t              max_vals;
 771 #endif
 772
 773 static void dump_bitfield(normal_or_bitfield *vals, size_t offset_bits,
 774                           const ir_initializer_t *initializer, ir_type *type)
 775 {
 776         unsigned char  last_bits = 0;
 777         ir_mode       *mode      = get_type_mode(type);
 778         tarval        *tv        = NULL;
 779         unsigned char  curr_bits;
 780         int            value_len;
 781         int            j;
 782
 783         switch(get_initializer_kind(initializer)) {
 784         case IR_INITIALIZER_NULL:
 785                 return;
 786         case IR_INITIALIZER_TARVAL:
 787                 tv = get_initializer_tarval_value(initializer);
 788                 break;
 789         case IR_INITIALIZER_CONST: {
 790                 ir_node *node = get_initializer_const_value(initializer);
 791                 if(!is_Const(node)) {
 792                         panic("bitfield initializer not a Const node");
 793                 }
 794                 tv = get_Const_tarval(node);
 795                 break;
 796         }
 797         case IR_INITIALIZER_COMPOUND:
 798                 panic("bitfield initializer is compound");
 799         }
 800         if (tv == NULL) {
 801                 panic("Couldn't get numeric value for bitfield initializer\n");
 802         }
 803
 804         /* normalize offset */
 805         vals        += offset_bits >> 3;
 806         offset_bits &= 7;
 807         value_len    = get_mode_size_bits(mode);
 808
 809         /* combine bits with existing bits */
 810         for (j = 0; value_len + (int) offset_bits > 0; ++j) {
 811                 assert((size_t) (vals - glob_vals) + j < max_vals);
 812                 assert(vals[j].kind == BITFIELD ||
 813                                 (vals[j].kind == NORMAL && vals[j].v.value == NULL));
 814                 vals[j].kind = BITFIELD;
 815                 curr_bits    = get_tarval_sub_bits(tv, j);
 816                 vals[j].v.bf_val
 817                         |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
 818                 value_len -= 8;
 819                 last_bits = curr_bits;
 820         }
 821 }
 822
 823 static void dump_ir_initializer(normal_or_bitfield *vals,
 824                                 const ir_initializer_t *initializer,
 825                                 ir_type *type)
 826 {
 827         assert((size_t) (vals - glob_vals) < max_vals);
 828
 829         switch(get_initializer_kind(initializer)) {
 830         case IR_INITIALIZER_NULL:
 831                 return;
 832         case IR_INITIALIZER_TARVAL: {
 833                 size_t i;
 834
 835                 assert(vals->kind != BITFIELD);
 836                 vals->kind     = TARVAL;
 837                 vals->v.tarval = get_initializer_tarval_value(initializer);
 838                 assert(get_type_mode(type) == get_tarval_mode(vals->v.tarval));
 839                 for(i = 1; i < get_type_size_bytes(type); ++i) {
 840                         vals[i].kind    = NORMAL;
 841                         vals[i].v.value = NULL;
 842                 }
 843                 return;
 844         }
 845         case IR_INITIALIZER_CONST: {
 846                 size_t i;
 847
 848                 assert(vals->kind != BITFIELD);
 849                 vals->kind    = NORMAL;
 850                 vals->v.value = get_initializer_const_value(initializer);
 851                 for(i = 1; i < get_type_size_bytes(type); ++i) {
 852                         vals[i].kind    = NORMAL;
 853                         vals[i].v.value = NULL;
 854                 }
 855                 return;
 856         }
 857         case IR_INITIALIZER_COMPOUND: {
 858                 size_t i = 0;
 859                 size_t n = get_initializer_compound_n_entries(initializer);
 860
 861                 if(is_Array_type(type)) {
 862                         ir_type *element_type = get_array_element_type(type);
 863                         size_t   skip         = get_type_size_bytes(element_type);
 864                         size_t   alignment    = get_type_alignment_bytes(element_type);
 865                         size_t   misalign     = skip % alignment;
 866                         if(misalign != 0) {
 867                                 skip += alignment - misalign;
 868                         }
 869
 870                         for(i = 0; i < n; ++i) {
 871                                 ir_initializer_t *sub_initializer
 872                                         = get_initializer_compound_value(initializer, i);
 873
 874                                 dump_ir_initializer(vals, sub_initializer, element_type);
 875
 876                                 vals += skip;
 877                         }
 878                 } else {
 879                         size_t n_members, i;
 880                         assert(is_compound_type(type));
 881                         n_members = get_compound_n_members(type);
 882                         for(i = 0; i < n_members; ++i) {
 883                                 ir_entity        *member    = get_compound_member(type, i);
 884                                 size_t            offset    = get_entity_offset(member);
 885                                 ir_type          *subtype   = get_entity_type(member);
 886                                 ir_mode          *mode      = get_type_mode(subtype);
 887                                 ir_initializer_t *sub_initializer;
 888
 889                                 assert(i < get_initializer_compound_n_entries(initializer));
 890                                 sub_initializer
 891                                         = get_initializer_compound_value(initializer, i);
 892
 893                                 if(mode != NULL) {
 894                                         size_t offset_bits
 895                                                 = get_entity_offset_bits_remainder(member);
 896                                         size_t value_len   = get_mode_size_bits(mode);
 897
 898                                         if(offset_bits != 0 ||
 899                                                 (value_len != 8 && value_len != 16 && value_len != 32
 900                                                  && value_len != 64)) {
 901                                                 dump_bitfield(&vals[offset], offset_bits,
 902                                                               sub_initializer, subtype);
 903                                                 continue;
 904                                         }
 905                                 }
 906
 907                                 dump_ir_initializer(&vals[offset], sub_initializer, subtype);
 908                         }
 909                 }
 910
 911                 return;
 912         }
 913         }
 914         panic("invalid ir_initializer kind found");
 915 }
 916
 917 static void dump_initializer(be_gas_decl_env_t *env, ir_entity *entity)
 918 {
 919         const ir_initializer_t *initializer = entity->attr.initializer;
 920         ir_type                *type;
 921         normal_or_bitfield     *vals;
 922         size_t                  size;
 923         size_t                  k;
 924
 925         if(initializer_is_string_const(initializer)) {
 926                 dump_string_initializer(initializer);
 927                 return;
 928         }
 929
 930         type = get_entity_type(entity);
 931         size = get_initializer_size(initializer, type);
 932
 933         if (size == 0)
 934                 return;
 935
 936         /*
 937          * In the worst case, every initializer allocates one byte.
 938          * Moreover, initializer might be big, do not allocate on stack.
 939          */
 940         vals = xcalloc(size, sizeof(vals[0]));
 941
 942 #ifndef NDEBUG
 943         glob_vals = vals;
 944         max_vals  = size;
 945 #endif
 946
 947         dump_ir_initializer(vals, initializer, type);
 948
 949         /* now write values sorted */
 950         for (k = 0; k < size; ) {
 951                 int space     = 0;
 952                 int elem_size = 1;
 953                 if (vals[k].kind == NORMAL) {
 954                         if(vals[k].v.value != NULL) {
 955                                 dump_atomic_init(env, vals[k].v.value);
 956                                 elem_size = get_mode_size_bytes(get_irn_mode(vals[k].v.value));
 957                         } else {
 958                                 elem_size = 0;
 959                         }
 960                 } else if(vals[k].kind == TARVAL) {
 961                         tarval *tv   = vals[k].v.tarval;
 962                         size_t  size = get_mode_size_bytes(get_tarval_mode(tv));
 963
 964                         assert(tv != NULL);
 965
 966                         elem_size = size;
 967                         dump_size_type(size);
 968                         dump_arith_tarval(tv, size);
 969                         be_emit_char('\n');
 970                         be_emit_write_line();
 971                 } else {
 972                         assert(vals[k].kind == BITFIELD);
 973                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
 974                         be_emit_write_line();
 975                 }
 976
 977                 k += elem_size;
 978                 while (k < size && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
 979                         ++space;
 980                         ++k;
 981                 }
 982
 983                 /* a gap */
 984                 if (space > 0) {
 985                         be_emit_irprintf("\t.skip\t%d\n", space);
 986                         be_emit_write_line();
 987                 }
 988         }
 989         xfree(vals);
 990 }
 991
 992 /**
 993  * Dump an initializer for a compound entity.
 994  */
 995 static void dump_compound_init(be_gas_decl_env_t *env, ir_entity *ent)
 996 {
 997         normal_or_bitfield *vals;
 998         int i, j, n;
 999         unsigned k, last_ofs;
1000
1001         if(ent->has_initializer) {
1002                 dump_initializer(env, ent);
1003                 return;
1004         }
1005
1006         n = get_compound_ent_n_values(ent);
1007
1008         /* Find the initializer size. Sorrily gcc support a nasty feature:
1009            The last field of a compound may be a flexible array. This allows
1010            initializers bigger than the type size. */
1011         last_ofs = get_type_size_bytes(get_entity_type(ent));
1012         for (i = 0; i < n; ++i) {
1013                 unsigned offset         = get_compound_ent_value_offset_bytes(ent, i);
1014                 unsigned bits_remainder = get_compound_ent_value_offset_bit_remainder(ent, i);
1015                 ir_node  *value         = get_compound_ent_value(ent, i);
1016                 unsigned value_len      = get_mode_size_bits(get_irn_mode(value));
1017
1018                 offset += (value_len + bits_remainder + 7) >> 3;
1019
1020                 if (offset > last_ofs) {
1021                         last_ofs = offset;
1022                 }
1023         }
1024
1025         /*
1026          * In the worst case, every initializer allocates one byte.
1027          * Moreover, initializer might be big, do not allocate on stack.
1028          */
1029         vals = xcalloc(last_ofs, sizeof(vals[0]));
1030
1031         /* collect the values and store them at the offsets */
1032         for (i = 0; i < n; ++i) {
1033                 unsigned offset      = get_compound_ent_value_offset_bytes(ent, i);
1034                 int      offset_bits = get_compound_ent_value_offset_bit_remainder(ent, i);
1035                 ir_node  *value      = get_compound_ent_value(ent, i);
1036                 int      value_len   = get_mode_size_bits(get_irn_mode(value));
1037
1038                 assert(offset_bits >= 0);
1039
1040                 if (offset_bits != 0 ||
1041                         (value_len != 8 && value_len != 16 && value_len != 32 && value_len != 64)) {
1042                         tarval *tv = get_atomic_init_tv(value);
1043                         unsigned char curr_bits, last_bits = 0;
1044                         if (tv == NULL) {
1045                                 panic("Couldn't get numeric value for bitfield initializer '%s'\n",
1046                                       get_entity_ld_name(ent));
1047                         }
1048                         /* normalize offset */
1049                         offset += offset_bits >> 3;
1050                         offset_bits &= 7;
1051
1052                         for (j = 0; value_len + offset_bits > 0; ++j) {
1053                                 assert(offset + j < last_ofs);
1054                                 assert(vals[offset + j].kind == BITFIELD || vals[offset + j].v.value == NULL);
1055                                 vals[offset + j].kind = BITFIELD;
1056                                 curr_bits = get_tarval_sub_bits(tv, j);
1057                                 vals[offset + j].v.bf_val |= (last_bits >> (8 - offset_bits)) | (curr_bits << offset_bits);
1058                                 value_len -= 8;
1059                                 last_bits = curr_bits;
1060                         }
1061                 } else {
1062                         int i;
1063
1064                         assert(offset < last_ofs);
1065                         assert(vals[offset].kind == NORMAL);
1066                         for (i = 1; i < value_len / 8; ++i) {
1067                                 assert(vals[offset + i].v.value == NULL);
1068                         }
1069                         vals[offset].v.value = value;
1070                 }
1071         }
1072
1073         /* now write them sorted */
1074         for (k = 0; k < last_ofs; ) {
1075                 int space = 0, skip = 0;
1076                 if (vals[k].kind == NORMAL) {
1077                         if(vals[k].v.value != NULL) {
1078                                 dump_atomic_init(env, vals[k].v.value);
1079                                 skip = get_mode_size_bytes(get_irn_mode(vals[k].v.value)) - 1;
1080                         } else {
1081                                 space = 1;
1082                         }
1083                 } else {
1084                         assert(vals[k].kind == BITFIELD);
1085                         be_emit_irprintf("\t.byte\t%d\n", vals[k].v.bf_val);
1086                 }
1087
1088                 ++k;
1089                 while (k < last_ofs && vals[k].kind == NORMAL && vals[k].v.value == NULL) {
1090                         ++space;
1091                         ++k;
1092                 }
1093                 space -= skip;
1094                 assert(space >= 0);
1095
1096                 /* a gap */
1097                 if (space > 0) {
1098                         be_emit_irprintf("\t.skip\t%d\n", space);
1099                         be_emit_write_line();
1100                 }
1101         }
1102         xfree(vals);
1103 }
1104
1105 static void emit_align(unsigned alignment)
1106 {
1107         if (!is_po2(alignment))
1108                 panic("alignment not a power of 2");
1109
1110         be_emit_irprintf(".p2align\t%u\n", log2_floor(alignment));
1111         be_emit_write_line();
1112 }
1113
1114 /**
1115  * Dump a global entity.
1116  *
1117  * @param env           the gas output environment
1118  * @param ent           the entity to be dumped
1119  */
1120 static void dump_global(be_gas_decl_env_t *env, ir_entity *ent)
1121 {
1122         ir_type          *type           = get_entity_type(ent);
1123         ident            *ld_ident       = get_entity_ld_ident(ent);
1124         unsigned          align          = get_type_alignment_bytes(type);
1125         int               emit_as_common = 0;
1126         be_gas_section_t  section        = env->section;
1127         ir_variability    variability    = get_entity_variability(ent);
1128         ir_visibility     visibility     = get_entity_visibility(ent);
1129
1130         if (is_Method_type(type) && section != GAS_SECTION_PIC_TRAMPOLINES) {
1131                 return;
1132         }
1133
1134         if (section != (be_gas_section_t) -1) {
1135                 emit_as_common = 0;
1136         } else if (variability == variability_constant) {
1137                 /* a constant entity, put it on the rdata */
1138                 section = GAS_SECTION_RODATA;
1139                 if (be_gas_flavour == GAS_FLAVOUR_MACH_O
1140                                 && ent_is_string_const(ent)) {
1141                         section = GAS_SECTION_CSTRING;
1142                 }
1143         } else if (variability == variability_uninitialized) {
1144                 /* uninitialized entity put it in bss segment */
1145                 section = GAS_SECTION_COMMON;
1146                 if (visibility != visibility_local)
1147                         emit_as_common = 1;
1148         } else {
1149                 section = GAS_SECTION_DATA;
1150         }
1151
1152         if(!emit_as_common) {
1153                 be_gas_emit_switch_section(section);
1154         }
1155
1156         be_dbg_variable(ent);
1157
1158         /* global or not global */
1159         if (visibility == visibility_external_visible && !emit_as_common) {
1160                 be_emit_cstring(".globl\t");
1161                 be_emit_ident(ld_ident);
1162                 be_emit_char('\n');
1163                 be_emit_write_line();
1164         } else if(visibility == visibility_external_allocated) {
1165                 be_emit_cstring(".globl\t");
1166                 be_emit_ident(ld_ident);
1167                 be_emit_char('\n');
1168                 be_emit_write_line();
1169                 /* we can return now... */
1170                 return;
1171         }
1172         /* alignment */
1173         if (align > 1 && !emit_as_common && section != GAS_SECTION_PIC_TRAMPOLINES
1174                         && section != GAS_SECTION_PIC_SYMBOLS) {
1175                 emit_align(align);
1176         }
1177
1178         if (!emit_as_common) {
1179                 be_emit_ident(ld_ident);
1180                 be_emit_cstring(":\n");
1181                 be_emit_write_line();
1182         }
1183
1184         if (variability == variability_uninitialized) {
1185                 if (emit_as_common) {
1186                         switch (be_gas_flavour) {
1187                         case GAS_FLAVOUR_ELF:
1188                         case GAS_FLAVOUR_MACH_O:
1189                         case GAS_FLAVOUR_YASM:
1190                                 be_emit_irprintf("\t.comm %s,%u,%u\n",
1191                                         get_id_str(ld_ident), get_type_size_bytes(type), align);
1192                                 be_emit_write_line();
1193                                 break;
1194                         case GAS_FLAVOUR_MINGW:
1195                                 be_emit_irprintf("\t.comm %s,%u # %u\n",
1196                                         get_id_str(ld_ident), get_type_size_bytes(type), align);
1197                                 be_emit_write_line();
1198                                 break;
1199                         }
1200                 } else if (section == GAS_SECTION_PIC_TRAMPOLINES) {
1201                         if (be_gas_flavour == GAS_FLAVOUR_MACH_O) {
1202                                 be_emit_cstring("\t.indirect_symbol ");
1203                                 be_emit_ident(get_entity_ident(ent));
1204                                 be_emit_char('\n');
1205                                 be_emit_write_line();
1206                                 be_emit_cstring("\thlt ; hlt ; hlt ; hlt ; hlt\n");
1207                                 be_emit_write_line();
1208                         } else {
1209                                 panic("PIC trampolines not yet supported in this gas mode");
1210                         }
1211                 } else {
1212                         be_emit_irprintf("\t.space %u\n", get_type_size_bytes(type));
1213                         be_emit_write_line();
1214                 }
1215         } else {
1216                 if (is_atomic_entity(ent)) {
1217                         dump_atomic_init(env, get_atomic_ent_value(ent));
1218                 } else {
1219                         /* sort_compound_ent_values(ent); */
1220
1221                         switch (get_type_tpop_code(get_entity_type(ent))) {
1222                         case tpo_array:
1223                                 if (ent_is_string_const(ent))
1224                                         dump_string_cst(ent);
1225                                 else
1226                                         dump_compound_init(env, ent);
1227                                 break;
1228                         case tpo_struct:
1229                         case tpo_class:
1230                         case tpo_union:
1231                                 dump_compound_init(env, ent);
1232                                 break;
1233                         default:
1234                                 assert(0);
1235                         }
1236                 }
1237         }
1238 }
1239
1240 /**
1241  * Dumps declarations of global variables and the initialization code.
1242  *
1243  * @param gt                a global like type, either the global or the TLS one
1244  * @param env               an environment
1245  * @param only_emit_marked  if non-zero, external allocated entities that do not have
1246  *                          its visited flag set are ignored
1247  */
1248 static void be_gas_dump_globals(ir_type *gt, be_gas_decl_env_t *env,
1249                                 int only_emit_marked)
1250 {
1251         int i, n = get_compound_n_members(gt);
1252         waitq *worklist = new_waitq();
1253
1254         if (only_emit_marked) {
1255                 for (i = 0; i < n; i++) {
1256                         ir_entity *ent = get_compound_member(gt, i);
1257                         if (is_entity_backend_marked(ent) ||
1258                             get_entity_visibility(ent) != visibility_external_allocated) {
1259                                 waitq_put(worklist, ent);
1260                                 set_entity_backend_marked(ent, 1);
1261                         }
1262                 }
1263         } else {
1264                 for (i = 0; i < n; i++) {
1265                         ir_entity *ent = get_compound_member(gt, i);
1266                         set_entity_backend_marked(ent, 1);
1267                         waitq_put(worklist, ent);
1268                 }
1269         }
1270
1271         env->worklist = worklist;
1272
1273         while (!waitq_empty(worklist)) {
1274                 ir_entity *ent = waitq_get(worklist);
1275
1276                 dump_global(env, ent);
1277         }
1278
1279         del_waitq(worklist);
1280         env->worklist = NULL;
1281 }
1282
1283 /************************************************************************/
1284
1285 /* Generate all entities. */
1286 void be_gas_emit_decls(const be_main_env_t *main_env,
1287                        int only_emit_marked_entities)
1288 {
1289         be_gas_decl_env_t env;
1290         memset(&env, 0, sizeof(env));
1291
1292         env.main_env = main_env;
1293
1294         /* dump global type */
1295         env.section = (be_gas_section_t) -1;
1296         be_gas_dump_globals(get_glob_type(), &env, only_emit_marked_entities);
1297         env.section = GAS_SECTION_TLS;
1298         be_gas_dump_globals(get_tls_type(), &env, only_emit_marked_entities);
1299         env.section = GAS_SECTION_CTOR;
1300         be_gas_dump_globals(get_constructors_type(), &env,
1301                             only_emit_marked_entities);
1302         env.section = GAS_SECTION_PIC_SYMBOLS;
1303         be_gas_dump_globals(main_env->pic_symbols_type, &env,
1304                             only_emit_marked_entities);
1305
1306         if (get_compound_n_members(main_env->pic_trampolines_type) > 0) {
1307                 env.section = GAS_SECTION_PIC_TRAMPOLINES;
1308                 be_gas_dump_globals(main_env->pic_trampolines_type, &env,
1309                                     only_emit_marked_entities);
1310                 if (be_gas_flavour == GAS_FLAVOUR_MACH_O) {
1311                         be_emit_cstring("\t.subsections_via_symbols\n");
1312                         be_emit_write_line();
1313                 }
1314         }
1315 }