gcc/defaults.h

   1 /* Definitions of various defaults for tm.h macros.
   2    Copyright (C) 1992, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
   3    2005, 2007, 2008, 2009
   4    Free Software Foundation, Inc.
   5    Contributed by Ron Guilmette (rfg@monkeys.com)
   6
   7 This file is part of GCC.
   8
   9 GCC is free software; you can redistribute it and/or modify it under
  10 the terms of the GNU General Public License as published by the Free
  11 Software Foundation; either version 3, or (at your option) any later
  12 version.
  13
  14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  17 for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with GCC; see the file COPYING3.  If not see
  21 <http://www.gnu.org/licenses/>.  */
  22
  23 #ifndef GCC_DEFAULTS_H
  24 #define GCC_DEFAULTS_H
  25
  26 #ifndef GET_ENVIRONMENT
  27 #define GET_ENVIRONMENT(VALUE, NAME) do { (VALUE) = getenv (NAME); } while (0)
  28 #endif
  29
  30 #define obstack_chunk_alloc     ((void *(*) (long)) xmalloc)
  31 #define obstack_chunk_free      ((void (*) (void *)) free)
  32 #define OBSTACK_CHUNK_SIZE      0
  33 #define gcc_obstack_init(OBSTACK)                       \
  34   _obstack_begin ((OBSTACK), OBSTACK_CHUNK_SIZE, 0,     \
  35                   obstack_chunk_alloc,                  \
  36                   obstack_chunk_free)
  37
  38 /* Store in OUTPUT a string (made with alloca) containing an
  39    assembler-name for a local static variable or function named NAME.
  40    LABELNO is an integer which is different for each call.  */
  41
  42 #ifndef ASM_PN_FORMAT
  43 # ifndef NO_DOT_IN_LABEL
  44 #  define ASM_PN_FORMAT "%s.%lu"
  45 # else
  46 #  ifndef NO_DOLLAR_IN_LABEL
  47 #   define ASM_PN_FORMAT "%s$%lu"
  48 #  else
  49 #   define ASM_PN_FORMAT "__%s_%lu"
  50 #  endif
  51 # endif
  52 #endif /* ! ASM_PN_FORMAT */
  53
  54 #ifndef ASM_FORMAT_PRIVATE_NAME
  55 # define ASM_FORMAT_PRIVATE_NAME(OUTPUT, NAME, LABELNO) \
  56   do { const char *const name_ = (NAME); \
  57        char *const output_ = (OUTPUT) = \
  58          (char *) alloca (strlen (name_) + 32); \
  59        sprintf (output_, ASM_PN_FORMAT, name_, (unsigned long)(LABELNO)); \
  60   } while (0)
  61 #endif
  62
  63 /* Choose a reasonable default for ASM_OUTPUT_ASCII.  */
  64
  65 #ifndef ASM_OUTPUT_ASCII
  66 #define ASM_OUTPUT_ASCII(MYFILE, MYSTRING, MYLENGTH) \
  67   do {                                                                        \
  68     FILE *_hide_asm_out_file = (MYFILE);                                      \
  69     const unsigned char *_hide_p = (const unsigned char *) (MYSTRING);        \
  70     int _hide_thissize = (MYLENGTH);                                          \
  71     {                                                                         \
  72       FILE *asm_out_file = _hide_asm_out_file;                                \
  73       const unsigned char *p = _hide_p;                                       \
  74       int thissize = _hide_thissize;                                          \
  75       int i;                                                                  \
  76       fprintf (asm_out_file, "\t.ascii \"");                                  \
  77                                                                               \
  78       for (i = 0; i < thissize; i++)                                          \
  79         {                                                                     \
  80           int c = p[i];                                                       \
  81           if (c == '\"' || c == '\\')                                         \
  82             putc ('\\', asm_out_file);                                        \
  83           if (ISPRINT(c))                                                     \
  84             putc (c, asm_out_file);                                           \
  85           else                                                                \
  86             {                                                                 \
  87               fprintf (asm_out_file, "\\%o", c);                              \
  88               /* After an octal-escape, if a digit follows,                   \
  89                  terminate one string constant and start another.             \
  90                  The VAX assembler fails to stop reading the escape           \
  91                  after three digits, so this is the only way we               \
  92                  can get it to parse the data properly.  */                   \
  93               if (i < thissize - 1 && ISDIGIT(p[i + 1]))                      \
  94                 fprintf (asm_out_file, "\"\n\t.ascii \"");                    \
  95           }                                                                   \
  96         }                                                                     \
  97       fprintf (asm_out_file, "\"\n");                                         \
  98     }                                                                         \
  99   }                                                                           \
 100   while (0)
 101 #endif
 102
 103 /* This is how we tell the assembler to equate two values.  */
 104 #ifdef SET_ASM_OP
 105 #ifndef ASM_OUTPUT_DEF
 106 #define ASM_OUTPUT_DEF(FILE,LABEL1,LABEL2)                              \
 107  do {   fprintf ((FILE), "%s", SET_ASM_OP);                             \
 108         assemble_name (FILE, LABEL1);                                   \
 109         fprintf (FILE, ",");                                            \
 110         assemble_name (FILE, LABEL2);                                   \
 111         fprintf (FILE, "\n");                                           \
 112   } while (0)
 113 #endif
 114 #endif
 115
 116 #if defined (HAVE_AS_TLS) && !defined (ASM_OUTPUT_TLS_COMMON)
 117 #define ASM_OUTPUT_TLS_COMMON(FILE, DECL, NAME, SIZE)                   \
 118   do                                                                    \
 119     {                                                                   \
 120       fprintf ((FILE), "\t.tls_common\t");                              \
 121       assemble_name ((FILE), (NAME));                                   \
 122       fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%u\n",          \
 123                (SIZE), DECL_ALIGN (DECL) / BITS_PER_UNIT);              \
 124     }                                                                   \
 125   while (0)
 126 #endif
 127
 128 /* Decide whether to defer emitting the assembler output for an equate
 129    of two values.  The default is to not defer output.  */
 130 #ifndef TARGET_DEFERRED_OUTPUT_DEFS
 131 #define TARGET_DEFERRED_OUTPUT_DEFS(DECL,TARGET) false
 132 #endif
 133
 134 /* This is how to output the definition of a user-level label named
 135    NAME, such as the label on a static function or variable NAME.  */
 136
 137 #ifndef ASM_OUTPUT_LABEL
 138 #define ASM_OUTPUT_LABEL(FILE,NAME) \
 139   do { assemble_name ((FILE), (NAME)); fputs (":\n", (FILE)); } while (0)
 140 #endif
 141
 142 /* Output the definition of a compiler-generated label named NAME.  */
 143 #ifndef ASM_OUTPUT_INTERNAL_LABEL
 144 #define ASM_OUTPUT_INTERNAL_LABEL(FILE,NAME)    \
 145   do {                                          \
 146     assemble_name_raw ((FILE), (NAME));         \
 147     fputs (":\n", (FILE));                      \
 148   } while (0)
 149 #endif
 150
 151 /* This is how to output a reference to a user-level label named NAME.  */
 152
 153 #ifndef ASM_OUTPUT_LABELREF
 154 #define ASM_OUTPUT_LABELREF(FILE,NAME)  asm_fprintf ((FILE), "%U%s", (NAME))
 155 #endif
 156
 157 /* Allow target to print debug info labels specially.  This is useful for
 158    VLIW targets, since debug info labels should go into the middle of
 159    instruction bundles instead of breaking them.  */
 160
 161 #ifndef ASM_OUTPUT_DEBUG_LABEL
 162 #define ASM_OUTPUT_DEBUG_LABEL(FILE, PREFIX, NUM) \
 163   (*targetm.asm_out.internal_label) (FILE, PREFIX, NUM)
 164 #endif
 165
 166 /* This is how we tell the assembler that a symbol is weak.  */
 167 #ifndef ASM_OUTPUT_WEAK_ALIAS
 168 #if defined (ASM_WEAKEN_LABEL) && defined (ASM_OUTPUT_DEF)
 169 #define ASM_OUTPUT_WEAK_ALIAS(STREAM, NAME, VALUE)      \
 170   do                                                    \
 171     {                                                   \
 172       ASM_WEAKEN_LABEL (STREAM, NAME);                  \
 173       if (VALUE)                                        \
 174         ASM_OUTPUT_DEF (STREAM, NAME, VALUE);           \
 175     }                                                   \
 176   while (0)
 177 #endif
 178 #endif
 179
 180 /* This is how we tell the assembler that a symbol is a weak alias to
 181    another symbol that doesn't require the other symbol to be defined.
 182    Uses of the former will turn into weak uses of the latter, i.e.,
 183    uses that, in case the latter is undefined, will not cause errors,
 184    and will add it to the symbol table as weak undefined.  However, if
 185    the latter is referenced directly, a strong reference prevails.  */
 186 #ifndef ASM_OUTPUT_WEAKREF
 187 #if defined HAVE_GAS_WEAKREF
 188 #define ASM_OUTPUT_WEAKREF(FILE, DECL, NAME, VALUE)                     \
 189   do                                                                    \
 190     {                                                                   \
 191       fprintf ((FILE), "\t.weakref\t");                                 \
 192       assemble_name ((FILE), (NAME));                                   \
 193       fprintf ((FILE), ",");                                            \
 194       assemble_name ((FILE), (VALUE));                                  \
 195       fprintf ((FILE), "\n");                                           \
 196     }                                                                   \
 197   while (0)
 198 #endif
 199 #endif
 200
 201 /* How to emit a .type directive.  */
 202 #ifndef ASM_OUTPUT_TYPE_DIRECTIVE
 203 #if defined TYPE_ASM_OP && defined TYPE_OPERAND_FMT
 204 #define ASM_OUTPUT_TYPE_DIRECTIVE(STREAM, NAME, TYPE)   \
 205   do                                                    \
 206     {                                                   \
 207       fputs (TYPE_ASM_OP, STREAM);                      \
 208       assemble_name (STREAM, NAME);                     \
 209       fputs (", ", STREAM);                             \
 210       fprintf (STREAM, TYPE_OPERAND_FMT, TYPE);         \
 211       putc ('\n', STREAM);                              \
 212     }                                                   \
 213   while (0)
 214 #endif
 215 #endif
 216
 217 /* How to emit a .size directive.  */
 218 #ifndef ASM_OUTPUT_SIZE_DIRECTIVE
 219 #ifdef SIZE_ASM_OP
 220 #define ASM_OUTPUT_SIZE_DIRECTIVE(STREAM, NAME, SIZE)   \
 221   do                                                    \
 222     {                                                   \
 223       HOST_WIDE_INT size_ = (SIZE);                     \
 224       fputs (SIZE_ASM_OP, STREAM);                      \
 225       assemble_name (STREAM, NAME);                     \
 226       fprintf (STREAM, ", " HOST_WIDE_INT_PRINT_DEC "\n", size_); \
 227     }                                                   \
 228   while (0)
 229
 230 #define ASM_OUTPUT_MEASURED_SIZE(STREAM, NAME)          \
 231   do                                                    \
 232     {                                                   \
 233       fputs (SIZE_ASM_OP, STREAM);                      \
 234       assemble_name (STREAM, NAME);                     \
 235       fputs (", .-", STREAM);                           \
 236       assemble_name (STREAM, NAME);                     \
 237       putc ('\n', STREAM);                              \
 238     }                                                   \
 239   while (0)
 240
 241 #endif
 242 #endif
 243
 244 /* This determines whether or not we support weak symbols.  */
 245 #ifndef SUPPORTS_WEAK
 246 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
 247 #define SUPPORTS_WEAK 1
 248 #else
 249 #define SUPPORTS_WEAK 0
 250 #endif
 251 #endif
 252
 253 /* This determines whether or not we support link-once semantics.  */
 254 #ifndef SUPPORTS_ONE_ONLY
 255 #ifdef MAKE_DECL_ONE_ONLY
 256 #define SUPPORTS_ONE_ONLY 1
 257 #else
 258 #define SUPPORTS_ONE_ONLY 0
 259 #endif
 260 #endif
 261
 262 /* This determines whether weak symbols must be left out of a static
 263    archive's table of contents.  Defining this macro to be nonzero has
 264    the consequence that certain symbols will not be made weak that
 265    otherwise would be.  The C++ ABI requires this macro to be zero;
 266    see the documentation.  */
 267 #ifndef TARGET_WEAK_NOT_IN_ARCHIVE_TOC
 268 #define TARGET_WEAK_NOT_IN_ARCHIVE_TOC 0
 269 #endif
 270
 271 /* This determines whether or not we need linkonce unwind information.  */
 272 #ifndef TARGET_USES_WEAK_UNWIND_INFO
 273 #define TARGET_USES_WEAK_UNWIND_INFO 0
 274 #endif
 275
 276 /* By default, there is no prefix on user-defined symbols.  */
 277 #ifndef USER_LABEL_PREFIX
 278 #define USER_LABEL_PREFIX ""
 279 #endif
 280
 281 /* If the target supports weak symbols, define TARGET_ATTRIBUTE_WEAK to
 282    provide a weak attribute.  Else define it to nothing.
 283
 284    This would normally belong in ansidecl.h, but SUPPORTS_WEAK is
 285    not available at that time.
 286
 287    Note, this is only for use by target files which we know are to be
 288    compiled by GCC.  */
 289 #ifndef TARGET_ATTRIBUTE_WEAK
 290 # if SUPPORTS_WEAK
 291 #  define TARGET_ATTRIBUTE_WEAK __attribute__ ((weak))
 292 # else
 293 #  define TARGET_ATTRIBUTE_WEAK
 294 # endif
 295 #endif
 296
 297 /* Determines whether we may use common symbols to represent one-only
 298    semantics (a.k.a. "vague linkage").  */
 299 #ifndef USE_COMMON_FOR_ONE_ONLY
 300 # define USE_COMMON_FOR_ONE_ONLY 1
 301 #endif
 302
 303 /* By default we can assume that all global symbols are in one namespace,
 304    across all shared libraries.  */
 305 #ifndef MULTIPLE_SYMBOL_SPACES
 306 # define MULTIPLE_SYMBOL_SPACES 0
 307 #endif
 308
 309 /* If the target supports init_priority C++ attribute, give
 310    SUPPORTS_INIT_PRIORITY a nonzero value.  */
 311 #ifndef SUPPORTS_INIT_PRIORITY
 312 #define SUPPORTS_INIT_PRIORITY 1
 313 #endif /* SUPPORTS_INIT_PRIORITY */
 314
 315 /* If duplicate library search directories can be removed from a
 316    linker command without changing the linker's semantics, give this
 317    symbol a nonzero.  */
 318 #ifndef LINK_ELIMINATE_DUPLICATE_LDIRECTORIES
 319 #define LINK_ELIMINATE_DUPLICATE_LDIRECTORIES 0
 320 #endif /* LINK_ELIMINATE_DUPLICATE_LDIRECTORIES */
 321
 322 /* If we have a definition of INCOMING_RETURN_ADDR_RTX, assume that
 323    the rest of the DWARF 2 frame unwind support is also provided.  */
 324 #if !defined (DWARF2_UNWIND_INFO) && defined (INCOMING_RETURN_ADDR_RTX) \
 325     && !defined (TARGET_UNWIND_INFO)
 326 #define DWARF2_UNWIND_INFO 1
 327 #endif
 328
 329 /* If we have named sections, and we're using crtstuff to run ctors,
 330    use them for registering eh frame information.  */
 331 #if defined (TARGET_ASM_NAMED_SECTION) && DWARF2_UNWIND_INFO \
 332     && !defined(EH_FRAME_IN_DATA_SECTION)
 333 #ifndef EH_FRAME_SECTION_NAME
 334 #define EH_FRAME_SECTION_NAME ".eh_frame"
 335 #endif
 336 #endif
 337
 338 /* On many systems, different EH table encodings are used under
 339    difference circumstances.  Some will require runtime relocations;
 340    some will not.  For those that do not require runtime relocations,
 341    we would like to make the table read-only.  However, since the
 342    read-only tables may need to be combined with read-write tables
 343    that do require runtime relocation, it is not safe to make the
 344    tables read-only unless the linker will merge read-only and
 345    read-write sections into a single read-write section.  If your
 346    linker does not have this ability, but your system is such that no
 347    encoding used with non-PIC code will ever require a runtime
 348    relocation, then you can define EH_TABLES_CAN_BE_READ_ONLY to 1 in
 349    your target configuration file.  */
 350 #ifndef EH_TABLES_CAN_BE_READ_ONLY
 351 #ifdef HAVE_LD_RO_RW_SECTION_MIXING
 352 #define EH_TABLES_CAN_BE_READ_ONLY 1
 353 #else
 354 #define EH_TABLES_CAN_BE_READ_ONLY 0
 355 #endif
 356 #endif
 357
 358 /* If we have named section and we support weak symbols, then use the
 359    .jcr section for recording java classes which need to be registered
 360    at program start-up time.  */
 361 #if defined (TARGET_ASM_NAMED_SECTION) && SUPPORTS_WEAK
 362 #ifndef JCR_SECTION_NAME
 363 #define JCR_SECTION_NAME ".jcr"
 364 #endif
 365 #endif
 366
 367 /* This decision to use a .jcr section can be overridden by defining
 368    USE_JCR_SECTION to 0 in target file.  This is necessary if target
 369    can define JCR_SECTION_NAME but does not have crtstuff or
 370    linker support for .jcr section.  */
 371 #ifndef TARGET_USE_JCR_SECTION
 372 #ifdef JCR_SECTION_NAME
 373 #define TARGET_USE_JCR_SECTION 1
 374 #else
 375 #define TARGET_USE_JCR_SECTION 0
 376 #endif
 377 #endif
 378
 379 /* Number of hardware registers that go into the DWARF-2 unwind info.
 380    If not defined, equals FIRST_PSEUDO_REGISTER  */
 381
 382 #ifndef DWARF_FRAME_REGISTERS
 383 #define DWARF_FRAME_REGISTERS FIRST_PSEUDO_REGISTER
 384 #endif
 385
 386 /* How to renumber registers for dbx and gdb.  If not defined, assume
 387    no renumbering is necessary.  */
 388
 389 #ifndef DBX_REGISTER_NUMBER
 390 #define DBX_REGISTER_NUMBER(REGNO) (REGNO)
 391 #endif
 392
 393 /* Default sizes for base C types.  If the sizes are different for
 394    your target, you should override these values by defining the
 395    appropriate symbols in your tm.h file.  */
 396
 397 #ifndef BITS_PER_UNIT
 398 #define BITS_PER_UNIT 8
 399 #endif
 400
 401 #ifndef BITS_PER_WORD
 402 #define BITS_PER_WORD (BITS_PER_UNIT * UNITS_PER_WORD)
 403 #endif
 404
 405 #ifndef CHAR_TYPE_SIZE
 406 #define CHAR_TYPE_SIZE BITS_PER_UNIT
 407 #endif
 408
 409 #ifndef BOOL_TYPE_SIZE
 410 /* `bool' has size and alignment `1', on almost all platforms.  */
 411 #define BOOL_TYPE_SIZE CHAR_TYPE_SIZE
 412 #endif
 413
 414 #ifndef SHORT_TYPE_SIZE
 415 #define SHORT_TYPE_SIZE (BITS_PER_UNIT * MIN ((UNITS_PER_WORD + 1) / 2, 2))
 416 #endif
 417
 418 #ifndef INT_TYPE_SIZE
 419 #define INT_TYPE_SIZE BITS_PER_WORD
 420 #endif
 421
 422 #ifndef LONG_TYPE_SIZE
 423 #define LONG_TYPE_SIZE BITS_PER_WORD
 424 #endif
 425
 426 #ifndef LONG_LONG_TYPE_SIZE
 427 #define LONG_LONG_TYPE_SIZE (BITS_PER_WORD * 2)
 428 #endif
 429
 430 #ifndef WCHAR_TYPE_SIZE
 431 #define WCHAR_TYPE_SIZE INT_TYPE_SIZE
 432 #endif
 433
 434 #ifndef FLOAT_TYPE_SIZE
 435 #define FLOAT_TYPE_SIZE BITS_PER_WORD
 436 #endif
 437
 438 #ifndef DOUBLE_TYPE_SIZE
 439 #define DOUBLE_TYPE_SIZE (BITS_PER_WORD * 2)
 440 #endif
 441
 442 #ifndef LONG_DOUBLE_TYPE_SIZE
 443 #define LONG_DOUBLE_TYPE_SIZE (BITS_PER_WORD * 2)
 444 #endif
 445
 446 #ifndef DECIMAL32_TYPE_SIZE
 447 #define DECIMAL32_TYPE_SIZE 32
 448 #endif
 449
 450 #ifndef DECIMAL64_TYPE_SIZE
 451 #define DECIMAL64_TYPE_SIZE 64
 452 #endif
 453
 454 #ifndef DECIMAL128_TYPE_SIZE
 455 #define DECIMAL128_TYPE_SIZE 128
 456 #endif
 457
 458 #ifndef SHORT_FRACT_TYPE_SIZE
 459 #define SHORT_FRACT_TYPE_SIZE BITS_PER_UNIT
 460 #endif
 461
 462 #ifndef FRACT_TYPE_SIZE
 463 #define FRACT_TYPE_SIZE (BITS_PER_UNIT * 2)
 464 #endif
 465
 466 #ifndef LONG_FRACT_TYPE_SIZE
 467 #define LONG_FRACT_TYPE_SIZE (BITS_PER_UNIT * 4)
 468 #endif
 469
 470 #ifndef LONG_LONG_FRACT_TYPE_SIZE
 471 #define LONG_LONG_FRACT_TYPE_SIZE (BITS_PER_UNIT * 8)
 472 #endif
 473
 474 #ifndef SHORT_ACCUM_TYPE_SIZE
 475 #define SHORT_ACCUM_TYPE_SIZE (SHORT_FRACT_TYPE_SIZE * 2)
 476 #endif
 477
 478 #ifndef ACCUM_TYPE_SIZE
 479 #define ACCUM_TYPE_SIZE (FRACT_TYPE_SIZE * 2)
 480 #endif
 481
 482 #ifndef LONG_ACCUM_TYPE_SIZE
 483 #define LONG_ACCUM_TYPE_SIZE (LONG_FRACT_TYPE_SIZE * 2)
 484 #endif
 485
 486 #ifndef LONG_LONG_ACCUM_TYPE_SIZE
 487 #define LONG_LONG_ACCUM_TYPE_SIZE (LONG_LONG_FRACT_TYPE_SIZE * 2)
 488 #endif
 489
 490 /* Width in bits of a pointer.  Mind the value of the macro `Pmode'.  */
 491 #ifndef POINTER_SIZE
 492 #define POINTER_SIZE BITS_PER_WORD
 493 #endif
 494
 495 #ifndef PIC_OFFSET_TABLE_REGNUM
 496 #define PIC_OFFSET_TABLE_REGNUM INVALID_REGNUM
 497 #endif
 498
 499 #ifndef TARGET_DLLIMPORT_DECL_ATTRIBUTES
 500 #define TARGET_DLLIMPORT_DECL_ATTRIBUTES 0
 501 #endif
 502
 503 #ifndef TARGET_DECLSPEC
 504 #if TARGET_DLLIMPORT_DECL_ATTRIBUTES
 505 /* If the target supports the "dllimport" attribute, users are
 506    probably used to the "__declspec" syntax.  */
 507 #define TARGET_DECLSPEC 1
 508 #else
 509 #define TARGET_DECLSPEC 0
 510 #endif
 511 #endif
 512
 513 /* By default, the preprocessor should be invoked the same way in C++
 514    as in C.  */
 515 #ifndef CPLUSPLUS_CPP_SPEC
 516 #ifdef CPP_SPEC
 517 #define CPLUSPLUS_CPP_SPEC CPP_SPEC
 518 #endif
 519 #endif
 520
 521 #ifndef ACCUMULATE_OUTGOING_ARGS
 522 #define ACCUMULATE_OUTGOING_ARGS 0
 523 #endif
 524
 525 /* Supply a default definition for PUSH_ARGS.  */
 526 #ifndef PUSH_ARGS
 527 #ifdef PUSH_ROUNDING
 528 #define PUSH_ARGS       !ACCUMULATE_OUTGOING_ARGS
 529 #else
 530 #define PUSH_ARGS       0
 531 #endif
 532 #endif
 533
 534 /* Decide whether a function's arguments should be processed
 535    from first to last or from last to first.
 536
 537    They should if the stack and args grow in opposite directions, but
 538    only if we have push insns.  */
 539
 540 #ifdef PUSH_ROUNDING
 541
 542 #ifndef PUSH_ARGS_REVERSED
 543 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
 544 #define PUSH_ARGS_REVERSED  PUSH_ARGS
 545 #endif
 546 #endif
 547
 548 #endif
 549
 550 #ifndef PUSH_ARGS_REVERSED
 551 #define PUSH_ARGS_REVERSED 0
 552 #endif
 553
 554 /* Default value for the alignment (in bits) a C conformant malloc has to
 555    provide. This default is intended to be safe and always correct.  */
 556 #ifndef MALLOC_ABI_ALIGNMENT
 557 #define MALLOC_ABI_ALIGNMENT BITS_PER_WORD
 558 #endif
 559
 560 /* If PREFERRED_STACK_BOUNDARY is not defined, set it to STACK_BOUNDARY.
 561    STACK_BOUNDARY is required.  */
 562 #ifndef PREFERRED_STACK_BOUNDARY
 563 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
 564 #endif
 565
 566 /* Set INCOMING_STACK_BOUNDARY to PREFERRED_STACK_BOUNDARY if it is not
 567    defined.  */
 568 #ifndef INCOMING_STACK_BOUNDARY
 569 #define INCOMING_STACK_BOUNDARY PREFERRED_STACK_BOUNDARY
 570 #endif
 571
 572 #ifndef TARGET_DEFAULT_PACK_STRUCT
 573 #define TARGET_DEFAULT_PACK_STRUCT 0
 574 #endif
 575
 576 /* By default, the C++ compiler will use function addresses in the
 577    vtable entries.  Setting this nonzero tells the compiler to use
 578    function descriptors instead.  The value of this macro says how
 579    many words wide the descriptor is (normally 2).  It is assumed
 580    that the address of a function descriptor may be treated as a
 581    pointer to a function.  */
 582 #ifndef TARGET_VTABLE_USES_DESCRIPTORS
 583 #define TARGET_VTABLE_USES_DESCRIPTORS 0
 584 #endif
 585
 586 /* By default, the vtable entries are void pointers, the so the alignment
 587    is the same as pointer alignment.  The value of this macro specifies
 588    the alignment of the vtable entry in bits.  It should be defined only
 589    when special alignment is necessary.  */
 590 #ifndef TARGET_VTABLE_ENTRY_ALIGN
 591 #define TARGET_VTABLE_ENTRY_ALIGN POINTER_SIZE
 592 #endif
 593
 594 /* There are a few non-descriptor entries in the vtable at offsets below
 595    zero.  If these entries must be padded (say, to preserve the alignment
 596    specified by TARGET_VTABLE_ENTRY_ALIGN), set this to the number of
 597    words in each data entry.  */
 598 #ifndef TARGET_VTABLE_DATA_ENTRY_DISTANCE
 599 #define TARGET_VTABLE_DATA_ENTRY_DISTANCE 1
 600 #endif
 601
 602 /* Decide whether it is safe to use a local alias for a virtual function
 603    when constructing thunks.  */
 604 #ifndef TARGET_USE_LOCAL_THUNK_ALIAS_P
 605 #ifdef ASM_OUTPUT_DEF
 606 #define TARGET_USE_LOCAL_THUNK_ALIAS_P(DECL) 1
 607 #else
 608 #define TARGET_USE_LOCAL_THUNK_ALIAS_P(DECL) 0
 609 #endif
 610 #endif
 611
 612 /* Select a format to encode pointers in exception handling data.  We
 613    prefer those that result in fewer dynamic relocations.  Assume no
 614    special support here and encode direct references.  */
 615 #ifndef ASM_PREFERRED_EH_DATA_FORMAT
 616 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE,GLOBAL)  DW_EH_PE_absptr
 617 #endif
 618
 619 /* By default, the C++ compiler will use the lowest bit of the pointer
 620    to function to indicate a pointer-to-member-function points to a
 621    virtual member function.  However, if FUNCTION_BOUNDARY indicates
 622    function addresses aren't always even, the lowest bit of the delta
 623    field will be used.  */
 624 #ifndef TARGET_PTRMEMFUNC_VBIT_LOCATION
 625 #define TARGET_PTRMEMFUNC_VBIT_LOCATION \
 626   (FUNCTION_BOUNDARY >= 2 * BITS_PER_UNIT \
 627    ? ptrmemfunc_vbit_in_pfn : ptrmemfunc_vbit_in_delta)
 628 #endif
 629
 630 #ifndef DEFAULT_GDB_EXTENSIONS
 631 #define DEFAULT_GDB_EXTENSIONS 1
 632 #endif
 633
 634 /* If more than one debugging type is supported, you must define
 635    PREFERRED_DEBUGGING_TYPE to choose the default.  */
 636
 637 #if 1 < (defined (DBX_DEBUGGING_INFO) + defined (SDB_DEBUGGING_INFO) \
 638          + defined (DWARF2_DEBUGGING_INFO) + defined (XCOFF_DEBUGGING_INFO) \
 639          + defined (VMS_DEBUGGING_INFO))
 640 #ifndef PREFERRED_DEBUGGING_TYPE
 641 #error You must define PREFERRED_DEBUGGING_TYPE
 642 #endif /* no PREFERRED_DEBUGGING_TYPE */
 643
 644 /* If only one debugging format is supported, define PREFERRED_DEBUGGING_TYPE
 645    here so other code needn't care.  */
 646 #elif defined DBX_DEBUGGING_INFO
 647 #define PREFERRED_DEBUGGING_TYPE DBX_DEBUG
 648
 649 #elif defined SDB_DEBUGGING_INFO
 650 #define PREFERRED_DEBUGGING_TYPE SDB_DEBUG
 651
 652 #elif defined DWARF2_DEBUGGING_INFO
 653 #define PREFERRED_DEBUGGING_TYPE DWARF2_DEBUG
 654
 655 #elif defined VMS_DEBUGGING_INFO
 656 #define PREFERRED_DEBUGGING_TYPE VMS_AND_DWARF2_DEBUG
 657
 658 #elif defined XCOFF_DEBUGGING_INFO
 659 #define PREFERRED_DEBUGGING_TYPE XCOFF_DEBUG
 660
 661 #else
 662 /* No debugging format is supported by this target.  */
 663 #define PREFERRED_DEBUGGING_TYPE NO_DEBUG
 664 #endif
 665
 666 #ifndef LARGEST_EXPONENT_IS_NORMAL
 667 #define LARGEST_EXPONENT_IS_NORMAL(SIZE) 0
 668 #endif
 669
 670 #ifndef ROUND_TOWARDS_ZERO
 671 #define ROUND_TOWARDS_ZERO 0
 672 #endif
 673
 674 #ifndef FLOAT_LIB_COMPARE_RETURNS_BOOL
 675 #define FLOAT_LIB_COMPARE_RETURNS_BOOL(MODE, COMPARISON) false
 676 #endif
 677
 678 /* True if the targets integer-comparison functions return { 0, 1, 2
 679    } to indicate { <, ==, > }.  False if { -1, 0, 1 } is used
 680    instead.  The libgcc routines are biased.  */
 681 #ifndef TARGET_LIB_INT_CMP_BIASED
 682 #define TARGET_LIB_INT_CMP_BIASED (true)
 683 #endif
 684
 685 /* If FLOAT_WORDS_BIG_ENDIAN is not defined in the header files,
 686    then the word-endianness is the same as for integers.  */
 687 #ifndef FLOAT_WORDS_BIG_ENDIAN
 688 #define FLOAT_WORDS_BIG_ENDIAN WORDS_BIG_ENDIAN
 689 #endif
 690
 691 #ifndef TARGET_FLT_EVAL_METHOD
 692 #define TARGET_FLT_EVAL_METHOD 0
 693 #endif
 694
 695 #ifndef TARGET_DEC_EVAL_METHOD
 696 #define TARGET_DEC_EVAL_METHOD 2
 697 #endif
 698
 699 #ifndef HOT_TEXT_SECTION_NAME
 700 #define HOT_TEXT_SECTION_NAME ".text.hot"
 701 #endif
 702
 703 #ifndef UNLIKELY_EXECUTED_TEXT_SECTION_NAME
 704 #define UNLIKELY_EXECUTED_TEXT_SECTION_NAME ".text.unlikely"
 705 #endif
 706
 707 #ifndef HAS_LONG_COND_BRANCH
 708 #define HAS_LONG_COND_BRANCH 0
 709 #endif
 710
 711 #ifndef HAS_LONG_UNCOND_BRANCH
 712 #define HAS_LONG_UNCOND_BRANCH 0
 713 #endif
 714
 715 /* By default, only attempt to parallelize bitwise operations, and
 716    possibly adds/subtracts using bit-twiddling.  */
 717 #ifndef UNITS_PER_SIMD_WORD
 718 #define UNITS_PER_SIMD_WORD(MODE) UNITS_PER_WORD
 719 #endif
 720
 721 /* Determine whether __cxa_atexit, rather than atexit, is used to
 722    register C++ destructors for local statics and global objects.  */
 723 #ifndef DEFAULT_USE_CXA_ATEXIT
 724 #define DEFAULT_USE_CXA_ATEXIT 0
 725 #endif
 726
 727 /* If none of these macros are defined, the port must use the new
 728    technique of defining constraints in the machine description.
 729    tm_p.h will define those macros that machine-independent code
 730    still uses.  */
 731 #if  !defined CONSTRAINT_LEN                    \
 732   && !defined REG_CLASS_FROM_LETTER             \
 733   && !defined REG_CLASS_FROM_CONSTRAINT         \
 734   && !defined CONST_OK_FOR_LETTER_P             \
 735   && !defined CONST_OK_FOR_CONSTRAINT_P         \
 736   && !defined CONST_DOUBLE_OK_FOR_LETTER_P      \
 737   && !defined CONST_DOUBLE_OK_FOR_CONSTRAINT_P  \
 738   && !defined EXTRA_CONSTRAINT                  \
 739   && !defined EXTRA_CONSTRAINT_STR              \
 740   && !defined EXTRA_MEMORY_CONSTRAINT           \
 741   && !defined EXTRA_ADDRESS_CONSTRAINT
 742
 743 #define USE_MD_CONSTRAINTS
 744
 745 #if GCC_VERSION >= 3000 && defined IN_GCC
 746 /* These old constraint macros shouldn't appear anywhere in a
 747    configuration using MD constraint definitions.  */
 748 #pragma GCC poison REG_CLASS_FROM_LETTER CONST_OK_FOR_LETTER_P \
 749                    CONST_DOUBLE_OK_FOR_LETTER_P EXTRA_CONSTRAINT
 750 #endif
 751
 752 #else /* old constraint mechanism in use */
 753
 754 /* Determine whether extra constraint letter should be handled
 755    via address reload (like 'o').  */
 756 #ifndef EXTRA_MEMORY_CONSTRAINT
 757 #define EXTRA_MEMORY_CONSTRAINT(C,STR) 0
 758 #endif
 759
 760 /* Determine whether extra constraint letter should be handled
 761    as an address (like 'p').  */
 762 #ifndef EXTRA_ADDRESS_CONSTRAINT
 763 #define EXTRA_ADDRESS_CONSTRAINT(C,STR) 0
 764 #endif
 765
 766 /* When a port defines CONSTRAINT_LEN, it should use DEFAULT_CONSTRAINT_LEN
 767    for all the characters that it does not want to change, so things like the
 768   'length' of a digit in a matching constraint is an implementation detail,
 769    and not part of the interface.  */
 770 #define DEFAULT_CONSTRAINT_LEN(C,STR) 1
 771
 772 #ifndef CONSTRAINT_LEN
 773 #define CONSTRAINT_LEN(C,STR) DEFAULT_CONSTRAINT_LEN (C, STR)
 774 #endif
 775
 776 #if defined (CONST_OK_FOR_LETTER_P) && ! defined (CONST_OK_FOR_CONSTRAINT_P)
 777 #define CONST_OK_FOR_CONSTRAINT_P(VAL,C,STR) CONST_OK_FOR_LETTER_P (VAL, C)
 778 #endif
 779
 780 #if defined (CONST_DOUBLE_OK_FOR_LETTER_P) && ! defined (CONST_DOUBLE_OK_FOR_CONSTRAINT_P)
 781 #define CONST_DOUBLE_OK_FOR_CONSTRAINT_P(OP,C,STR) \
 782   CONST_DOUBLE_OK_FOR_LETTER_P (OP, C)
 783 #endif
 784
 785 #ifndef REG_CLASS_FROM_CONSTRAINT
 786 #define REG_CLASS_FROM_CONSTRAINT(C,STR) REG_CLASS_FROM_LETTER (C)
 787 #endif
 788
 789 #if defined (EXTRA_CONSTRAINT) && ! defined (EXTRA_CONSTRAINT_STR)
 790 #define EXTRA_CONSTRAINT_STR(OP, C,STR) EXTRA_CONSTRAINT (OP, C)
 791 #endif
 792
 793 #endif /* old constraint mechanism in use */
 794
 795 #ifndef REGISTER_MOVE_COST
 796 #define REGISTER_MOVE_COST(m, x, y) 2
 797 #endif
 798
 799 /* Determine whether the entire c99 runtime
 800    is present in the runtime library.  */
 801 #ifndef TARGET_C99_FUNCTIONS
 802 #define TARGET_C99_FUNCTIONS 0
 803 #endif
 804
 805 /* Determine whether the target runtime library has
 806    a sincos implementation following the GNU extension.  */
 807 #ifndef TARGET_HAS_SINCOS
 808 #define TARGET_HAS_SINCOS 0
 809 #endif
 810
 811 /* Indicate that CLZ and CTZ are undefined at zero.  */
 812 #ifndef CLZ_DEFINED_VALUE_AT_ZERO
 813 #define CLZ_DEFINED_VALUE_AT_ZERO(MODE, VALUE)  0
 814 #endif
 815 #ifndef CTZ_DEFINED_VALUE_AT_ZERO
 816 #define CTZ_DEFINED_VALUE_AT_ZERO(MODE, VALUE)  0
 817 #endif
 818
 819 /* Provide a default value for STORE_FLAG_VALUE.  */
 820 #ifndef STORE_FLAG_VALUE
 821 #define STORE_FLAG_VALUE  1
 822 #endif
 823
 824 /* This macro is used to determine what the largest unit size that
 825    move_by_pieces can use is.  */
 826
 827 /* MOVE_MAX_PIECES is the number of bytes at a time which we can
 828    move efficiently, as opposed to  MOVE_MAX which is the maximum
 829    number of bytes we can move with a single instruction.  */
 830
 831 #ifndef MOVE_MAX_PIECES
 832 #define MOVE_MAX_PIECES   MOVE_MAX
 833 #endif
 834
 835 #ifndef STACK_POINTER_OFFSET
 836 #define STACK_POINTER_OFFSET    0
 837 #endif
 838
 839 #ifndef LOCAL_REGNO
 840 #define LOCAL_REGNO(REGNO)  0
 841 #endif
 842
 843 /* EXIT_IGNORE_STACK should be nonzero if, when returning from a function,
 844    the stack pointer does not matter.  The value is tested only in
 845    functions that have frame pointers.  */
 846 #ifndef EXIT_IGNORE_STACK
 847 #define EXIT_IGNORE_STACK 0
 848 #endif
 849
 850 /* Assume that case vectors are not pc-relative.  */
 851 #ifndef CASE_VECTOR_PC_RELATIVE
 852 #define CASE_VECTOR_PC_RELATIVE 0
 853 #endif
 854
 855 /* Assume that trampolines need function alignment.  */
 856 #ifndef TRAMPOLINE_ALIGNMENT
 857 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
 858 #endif
 859
 860 /* Register mappings for target machines without register windows.  */
 861 #ifndef INCOMING_REGNO
 862 #define INCOMING_REGNO(N) (N)
 863 #endif
 864
 865 #ifndef OUTGOING_REGNO
 866 #define OUTGOING_REGNO(N) (N)
 867 #endif
 868
 869 #ifndef SHIFT_COUNT_TRUNCATED
 870 #define SHIFT_COUNT_TRUNCATED 0
 871 #endif
 872
 873 #ifndef LEGITIMIZE_ADDRESS
 874 #define LEGITIMIZE_ADDRESS(X, OLDX, MODE, WIN)
 875 #endif
 876
 877 #ifndef LEGITIMATE_PIC_OPERAND_P
 878 #define LEGITIMATE_PIC_OPERAND_P(X) 1
 879 #endif
 880
 881 #ifndef TARGET_MEM_CONSTRAINT
 882 #define TARGET_MEM_CONSTRAINT 'm'
 883 #endif
 884
 885 #ifndef REVERSIBLE_CC_MODE
 886 #define REVERSIBLE_CC_MODE(MODE) 0
 887 #endif
 888
 889 /* Biggest alignment supported by the object file format of this machine.  */
 890 #ifndef MAX_OFILE_ALIGNMENT
 891 #define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT
 892 #endif
 893
 894 #ifndef FRAME_GROWS_DOWNWARD
 895 #define FRAME_GROWS_DOWNWARD 0
 896 #endif
 897
 898 /* On most machines, the CFA coincides with the first incoming parm.  */
 899 #ifndef ARG_POINTER_CFA_OFFSET
 900 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
 901 #endif
 902
 903 /* On most machines, we use the CFA as DW_AT_frame_base.  */
 904 #ifndef CFA_FRAME_BASE_OFFSET
 905 #define CFA_FRAME_BASE_OFFSET(FNDECL) 0
 906 #endif
 907
 908 /* The offset from the incoming value of %sp to the top of the stack frame
 909    for the current function.  */
 910 #ifndef INCOMING_FRAME_SP_OFFSET
 911 #define INCOMING_FRAME_SP_OFFSET 0
 912 #endif
 913
 914 #ifndef HARD_REGNO_NREGS_HAS_PADDING
 915 #define HARD_REGNO_NREGS_HAS_PADDING(REGNO, MODE) 0
 916 #define HARD_REGNO_NREGS_WITH_PADDING(REGNO, MODE) -1
 917 #endif
 918
 919 #ifndef OUTGOING_REG_PARM_STACK_SPACE
 920 #define OUTGOING_REG_PARM_STACK_SPACE(FNTYPE) 0
 921 #endif
 922
 923 /* MAX_STACK_ALIGNMENT is the maximum stack alignment guaranteed by
 924    the backend.  MAX_SUPPORTED_STACK_ALIGNMENT is the maximum best
 925    effort stack alignment supported by the backend.  If the backend
 926    supports stack alignment, MAX_SUPPORTED_STACK_ALIGNMENT and
 927    MAX_STACK_ALIGNMENT are the same.  Otherwise, the incoming stack
 928    boundary will limit the maximum guaranteed stack alignment.  */
 929 #ifdef MAX_STACK_ALIGNMENT
 930 #define MAX_SUPPORTED_STACK_ALIGNMENT MAX_STACK_ALIGNMENT
 931 #else
 932 #define MAX_STACK_ALIGNMENT STACK_BOUNDARY
 933 #define MAX_SUPPORTED_STACK_ALIGNMENT PREFERRED_STACK_BOUNDARY
 934 #endif
 935
 936 #define SUPPORTS_STACK_ALIGNMENT (MAX_STACK_ALIGNMENT > STACK_BOUNDARY)
 937
 938 #ifndef LOCAL_ALIGNMENT
 939 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
 940 #endif
 941
 942 #ifndef STACK_SLOT_ALIGNMENT
 943 #define STACK_SLOT_ALIGNMENT(TYPE,MODE,ALIGN) \
 944   ((TYPE) ? LOCAL_ALIGNMENT ((TYPE), (ALIGN)) : (ALIGN))
 945 #endif
 946
 947 /* Alignment value for attribute ((aligned)).  */
 948 #ifndef ATTRIBUTE_ALIGNED_VALUE
 949 #define ATTRIBUTE_ALIGNED_VALUE BIGGEST_ALIGNMENT
 950 #endif
 951
 952 #endif  /* ! GCC_DEFAULTS_H */