1 /* elfos.h -- operating system specific defines to be used when 2 targeting GCC for some generic ELF system 3 Copyright (C) 1991, 1994, 1995, 1999, 2000, 2001, 2002 4 Free Software Foundation, Inc. 5 Based on svr4.h contributed by Ron Guilmette (rfg@netcom.com). 6 7 This file is part of GNU CC. 8 9 GNU CC is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 2, or (at your option) 12 any later version. 13 14 GNU CC is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with GNU CC; see the file COPYING. If not, write to 21 the Free Software Foundation, 59 Temple Place - Suite 330, 22 Boston, MA 02111-1307, USA. */ 23 24 25 /* Define a symbol indicating that we are using elfos.h. 26 Some CPU specific configuration files use this. */ 27 #define USING_ELFOS_H 28 29 /* The prefix to add to user-visible assembler symbols. 30 31 For ELF systems the convention is *not* to prepend a leading 32 underscore onto user-level symbol names. */ 33 34 #undef USER_LABEL_PREFIX 35 #define USER_LABEL_PREFIX "" 36 37 /* Biggest alignment supported by the object file format of this 38 machine. Use this macro to limit the alignment which can be 39 specified using the `__attribute__ ((aligned (N)))' construct. If 40 not defined, the default value is `BIGGEST_ALIGNMENT'. */ 41 #ifndef MAX_OFILE_ALIGNMENT 42 #define MAX_OFILE_ALIGNMENT (32768 * 8) 43 #endif 44 45 /* Use periods rather than dollar signs in special g++ assembler names. */ 46 47 #define NO_DOLLAR_IN_LABEL 48 49 /* Writing `int' for a bit-field forces int alignment for the structure. */ 50 51 #ifndef PCC_BITFIELD_TYPE_MATTERS 52 #define PCC_BITFIELD_TYPE_MATTERS 1 53 #endif 54 55 /* Implicit library calls should use memcpy, not bcopy, etc. */ 56 57 #define TARGET_MEM_FUNCTIONS 58 59 /* Handle #pragma weak and #pragma pack. */ 60 61 #define HANDLE_SYSV_PRAGMA 1 62 63 /* System V Release 4 uses DWARF debugging info. */ 64 65 #define DWARF_DEBUGGING_INFO 1 66 67 /* All ELF targets can support DWARF-2. */ 68 69 #define DWARF2_DEBUGGING_INFO 1 70 71 /* The GNU tools operate better with dwarf2, and it is required by some 72 psABI's. Since we don't have any native tools to be compatible with, 73 default to dwarf2. */ 74 75 #ifndef PREFERRED_DEBUGGING_TYPE 76 #define PREFERRED_DEBUGGING_TYPE DWARF2_DEBUG 77 #endif 78 79 /* All SVR4 targets use the ELF object file format. */ 80 #define OBJECT_FORMAT_ELF 81 82 83 /* Output #ident as a .ident. */ 84 85 #define ASM_OUTPUT_IDENT(FILE, NAME) \ 86 fprintf (FILE, "%s\"%s\"\n", IDENT_ASM_OP, NAME); 87 88 #define IDENT_ASM_OP "\t.ident\t" 89 90 #undef SET_ASM_OP 91 #define SET_ASM_OP "\t.set\t" 92 93 /* This is how to begin an assembly language file. Most svr4 assemblers want 94 at least a .file directive to come first, and some want to see a .version 95 directive come right after that. Here we just establish a default 96 which generates only the .file directive. If you need a .version 97 directive for any specific target, you should override this definition 98 in the target-specific file which includes this one. */ 99 100 #undef ASM_FILE_START 101 #define ASM_FILE_START(FILE) \ 102 output_file_directive ((FILE), main_input_filename) 103 104 /* This is how to allocate empty space in some section. The .zero 105 pseudo-op is used for this on most svr4 assemblers. */ 106 107 #define SKIP_ASM_OP "\t.zero\t" 108 109 #undef ASM_OUTPUT_SKIP 110 #define ASM_OUTPUT_SKIP(FILE, SIZE) \ 111 fprintf (FILE, "%s%u\n", SKIP_ASM_OP, (SIZE)) 112 113 /* This is how to output an internal numbered label where 114 PREFIX is the class of label and NUM is the number within the class. 115 116 For most svr4 systems, the convention is that any symbol which begins 117 with a period is not put into the linker symbol table by the assembler. */ 118 119 #undef ASM_OUTPUT_INTERNAL_LABEL 120 #define ASM_OUTPUT_INTERNAL_LABEL(FILE, PREFIX, NUM) \ 121 do \ 122 { \ 123 fprintf (FILE, ".%s%u:\n", PREFIX, (unsigned) (NUM)); \ 124 } \ 125 while (0) 126 127 /* This is how to store into the string LABEL 128 the symbol_ref name of an internal numbered label where 129 PREFIX is the class of label and NUM is the number within the class. 130 This is suitable for output with `assemble_name'. 131 132 For most svr4 systems, the convention is that any symbol which begins 133 with a period is not put into the linker symbol table by the assembler. */ 134 135 #undef ASM_GENERATE_INTERNAL_LABEL 136 #define ASM_GENERATE_INTERNAL_LABEL(LABEL, PREFIX, NUM) \ 137 do \ 138 { \ 139 sprintf (LABEL, "*.%s%u", PREFIX, (unsigned) (NUM)); \ 140 } \ 141 while (0) 142 143 /* Output the label which precedes a jumptable. Note that for all svr4 144 systems where we actually generate jumptables (which is to say every 145 svr4 target except i386, where we use casesi instead) we put the jump- 146 tables into the .rodata section and since other stuff could have been 147 put into the .rodata section prior to any given jumptable, we have to 148 make sure that the location counter for the .rodata section gets pro- 149 perly re-aligned prior to the actual beginning of the jump table. */ 150 151 #undef ALIGN_ASM_OP 152 #define ALIGN_ASM_OP "\t.align\t" 153 154 #ifndef ASM_OUTPUT_BEFORE_CASE_LABEL 155 #define ASM_OUTPUT_BEFORE_CASE_LABEL(FILE, PREFIX, NUM, TABLE) \ 156 ASM_OUTPUT_ALIGN ((FILE), 2); 157 #endif 158 159 #undef ASM_OUTPUT_CASE_LABEL 160 #define ASM_OUTPUT_CASE_LABEL(FILE, PREFIX, NUM, JUMPTABLE) \ 161 do \ 162 { \ 163 ASM_OUTPUT_BEFORE_CASE_LABEL (FILE, PREFIX, NUM, JUMPTABLE) \ 164 ASM_OUTPUT_INTERNAL_LABEL (FILE, PREFIX, NUM); \ 165 } \ 166 while (0) 167 168 /* The standard SVR4 assembler seems to require that certain builtin 169 library routines (e.g. .udiv) be explicitly declared as .globl 170 in each assembly file where they are referenced. */ 171 172 #define ASM_OUTPUT_EXTERNAL_LIBCALL(FILE, FUN) \ 173 (*targetm.asm_out.globalize_label) (FILE, XSTR (FUN, 0)) 174 175 /* This says how to output assembler code to declare an 176 uninitialized external linkage data object. Under SVR4, 177 the linker seems to want the alignment of data objects 178 to depend on their types. We do exactly that here. */ 179 180 #define COMMON_ASM_OP "\t.comm\t" 181 182 #undef ASM_OUTPUT_ALIGNED_COMMON 183 #define ASM_OUTPUT_ALIGNED_COMMON(FILE, NAME, SIZE, ALIGN) \ 184 do \ 185 { \ 186 fprintf ((FILE), "%s", COMMON_ASM_OP); \ 187 assemble_name ((FILE), (NAME)); \ 188 fprintf ((FILE), ",%u,%u\n", (SIZE), (ALIGN) / BITS_PER_UNIT); \ 189 } \ 190 while (0) 191 192 /* This says how to output assembler code to declare an 193 uninitialized internal linkage data object. Under SVR4, 194 the linker seems to want the alignment of data objects 195 to depend on their types. We do exactly that here. */ 196 197 #define LOCAL_ASM_OP "\t.local\t" 198 199 #undef ASM_OUTPUT_ALIGNED_LOCAL 200 #define ASM_OUTPUT_ALIGNED_LOCAL(FILE, NAME, SIZE, ALIGN) \ 201 do \ 202 { \ 203 fprintf ((FILE), "%s", LOCAL_ASM_OP); \ 204 assemble_name ((FILE), (NAME)); \ 205 fprintf ((FILE), "\n"); \ 206 ASM_OUTPUT_ALIGNED_COMMON (FILE, NAME, SIZE, ALIGN); \ 207 } \ 208 while (0) 209 210 /* This is the pseudo-op used to generate a contiguous sequence of byte 211 values from a double-quoted string WITHOUT HAVING A TERMINATING NUL 212 AUTOMATICALLY APPENDED. This is the same for most svr4 assemblers. */ 213 214 #undef ASCII_DATA_ASM_OP 215 #define ASCII_DATA_ASM_OP "\t.ascii\t" 216 217 /* Support a read-only data section. */ 218 #define READONLY_DATA_SECTION_ASM_OP "\t.section\t.rodata" 219 220 /* On svr4, we *do* have support for the .init and .fini sections, and we 221 can put stuff in there to be executed before and after `main'. We let 222 crtstuff.c and other files know this by defining the following symbols. 223 The definitions say how to change sections to the .init and .fini 224 sections. This is the same for all known svr4 assemblers. */ 225 226 #define INIT_SECTION_ASM_OP "\t.section\t.init" 227 #define FINI_SECTION_ASM_OP "\t.section\t.fini" 228 229 /* Output assembly directive to move to the beginning of current section. */ 230 #ifdef HAVE_GAS_SUBSECTION_ORDERING 231 # define ASM_SECTION_START_OP "\t.subsection\t-1" 232 # define ASM_OUTPUT_SECTION_START(FILE) \ 233 fprintf ((FILE), "%s\n", ASM_SECTION_START_OP) 234 #endif 235 236 #define MAKE_DECL_ONE_ONLY(DECL) (DECL_WEAK (DECL) = 1) 237 238 /* Switch into a generic section. */ 239 #define TARGET_ASM_NAMED_SECTION default_elf_asm_named_section 240 241 #undef TARGET_ASM_SELECT_RTX_SECTION 242 #define TARGET_ASM_SELECT_RTX_SECTION default_elf_select_rtx_section 243 #undef TARGET_ASM_SELECT_SECTION 244 #define TARGET_ASM_SELECT_SECTION default_elf_select_section 245 246 /* Define the strings used for the special svr4 .type and .size directives. 247 These strings generally do not vary from one system running svr4 to 248 another, but if a given system (e.g. m88k running svr) needs to use 249 different pseudo-op names for these, they may be overridden in the 250 file which includes this one. */ 251 252 #define TYPE_ASM_OP "\t.type\t" 253 #define SIZE_ASM_OP "\t.size\t" 254 255 /* This is how we tell the assembler that a symbol is weak. */ 256 257 #define ASM_WEAKEN_LABEL(FILE, NAME) \ 258 do \ 259 { \ 260 fputs ("\t.weak\t", (FILE)); \ 261 assemble_name ((FILE), (NAME)); \ 262 fputc ('\n', (FILE)); \ 263 } \ 264 while (0) 265 266 /* The following macro defines the format used to output the second 267 operand of the .type assembler directive. Different svr4 assemblers 268 expect various different forms for this operand. The one given here 269 is just a default. You may need to override it in your machine- 270 specific tm.h file (depending upon the particulars of your assembler). */ 271 272 #define TYPE_OPERAND_FMT "@%s" 273 274 /* Write the extra assembler code needed to declare a function's result. 275 Most svr4 assemblers don't require any special declaration of the 276 result value, but there are exceptions. */ 277 278 #ifndef ASM_DECLARE_RESULT 279 #define ASM_DECLARE_RESULT(FILE, RESULT) 280 #endif 281 282 /* These macros generate the special .type and .size directives which 283 are used to set the corresponding fields of the linker symbol table 284 entries in an ELF object file under SVR4. These macros also output 285 the starting labels for the relevant functions/objects. */ 286 287 /* Write the extra assembler code needed to declare a function properly. 288 Some svr4 assemblers need to also have something extra said about the 289 function's return value. We allow for that here. */ 290 291 #ifndef ASM_DECLARE_FUNCTION_NAME 292 #define ASM_DECLARE_FUNCTION_NAME(FILE, NAME, DECL) \ 293 do \ 294 { \ 295 ASM_OUTPUT_TYPE_DIRECTIVE (FILE, NAME, "function"); \ 296 ASM_DECLARE_RESULT (FILE, DECL_RESULT (DECL)); \ 297 ASM_OUTPUT_LABEL (FILE, NAME); \ 298 } \ 299 while (0) 300 #endif 301 302 /* Write the extra assembler code needed to declare an object properly. */ 303 304 #define ASM_DECLARE_OBJECT_NAME(FILE, NAME, DECL) \ 305 do \ 306 { \ 307 HOST_WIDE_INT size; \ 308 \ 309 ASM_OUTPUT_TYPE_DIRECTIVE (FILE, NAME, "object"); \ 310 \ 311 size_directive_output = 0; \ 312 if (!flag_inhibit_size_directive \ 313 && (DECL) && DECL_SIZE (DECL)) \ 314 { \ 315 size_directive_output = 1; \ 316 size = int_size_in_bytes (TREE_TYPE (DECL)); \ 317 ASM_OUTPUT_SIZE_DIRECTIVE (FILE, NAME, size); \ 318 } \ 319 \ 320 ASM_OUTPUT_LABEL (FILE, NAME); \ 321 } \ 322 while (0) 323 324 /* Output the size directive for a decl in rest_of_decl_compilation 325 in the case where we did not do so before the initializer. 326 Once we find the error_mark_node, we know that the value of 327 size_directive_output was set 328 by ASM_DECLARE_OBJECT_NAME when it was run for the same decl. */ 329 330 #define ASM_FINISH_DECLARE_OBJECT(FILE, DECL, TOP_LEVEL, AT_END)\ 331 do \ 332 { \ 333 const char *name = XSTR (XEXP (DECL_RTL (DECL), 0), 0); \ 334 HOST_WIDE_INT size; \ 335 \ 336 if (!flag_inhibit_size_directive \ 337 && DECL_SIZE (DECL) \ 338 && ! AT_END && TOP_LEVEL \ 339 && DECL_INITIAL (DECL) == error_mark_node \ 340 && !size_directive_output) \ 341 { \ 342 size_directive_output = 1; \ 343 size = int_size_in_bytes (TREE_TYPE (DECL)); \ 344 ASM_OUTPUT_SIZE_DIRECTIVE (FILE, name, size); \ 345 } \ 346 } \ 347 while (0) 348 349 /* This is how to declare the size of a function. */ 350 #ifndef ASM_DECLARE_FUNCTION_SIZE 351 #define ASM_DECLARE_FUNCTION_SIZE(FILE, FNAME, DECL) \ 352 do \ 353 { \ 354 if (!flag_inhibit_size_directive) \ 355 ASM_OUTPUT_MEASURED_SIZE (FILE, FNAME); \ 356 } \ 357 while (0) 358 #endif 359 360 /* A table of bytes codes used by the ASM_OUTPUT_ASCII and 361 ASM_OUTPUT_LIMITED_STRING macros. Each byte in the table 362 corresponds to a particular byte value [0..255]. For any 363 given byte value, if the value in the corresponding table 364 position is zero, the given character can be output directly. 365 If the table value is 1, the byte must be output as a \ooo 366 octal escape. If the tables value is anything else, then the 367 byte value should be output as a \ followed by the value 368 in the table. Note that we can use standard UN*X escape 369 sequences for many control characters, but we don't use 370 \a to represent BEL because some svr4 assemblers (e.g. on 371 the i386) don't know about that. Also, we don't use \v 372 since some versions of gas, such as 2.2 did not accept it. */ 373 374 #define ESCAPES \ 375 "\1\1\1\1\1\1\1\1btn\1fr\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\ 376 \0\0\"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\ 377 \0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\\\0\0\0\ 378 \0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\1\ 379 \1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\ 380 \1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\ 381 \1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\ 382 \1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1" 383 384 /* Some svr4 assemblers have a limit on the number of characters which 385 can appear in the operand of a .string directive. If your assembler 386 has such a limitation, you should define STRING_LIMIT to reflect that 387 limit. Note that at least some svr4 assemblers have a limit on the 388 actual number of bytes in the double-quoted string, and that they 389 count each character in an escape sequence as one byte. Thus, an 390 escape sequence like \377 would count as four bytes. 391 392 If your target assembler doesn't support the .string directive, you 393 should define this to zero. 394 */ 395 396 #define STRING_LIMIT ((unsigned) 256) 397 398 #define STRING_ASM_OP "\t.string\t" 399 400 /* The routine used to output NUL terminated strings. We use a special 401 version of this for most svr4 targets because doing so makes the 402 generated assembly code more compact (and thus faster to assemble) 403 as well as more readable, especially for targets like the i386 404 (where the only alternative is to output character sequences as 405 comma separated lists of numbers). */ 406 407 #define ASM_OUTPUT_LIMITED_STRING(FILE, STR) \ 408 do \ 409 { \ 410 register const unsigned char *_limited_str = \ 411 (const unsigned char *) (STR); \ 412 register unsigned ch; \ 413 \ 414 fprintf ((FILE), "%s\"", STRING_ASM_OP); \ 415 \ 416 for (; (ch = *_limited_str); _limited_str++) \ 417 { \ 418 register int escape; \ 419 \ 420 switch (escape = ESCAPES[ch]) \ 421 { \ 422 case 0: \ 423 putc (ch, (FILE)); \ 424 break; \ 425 case 1: \ 426 fprintf ((FILE), "\\%03o", ch); \ 427 break; \ 428 default: \ 429 putc ('\\', (FILE)); \ 430 putc (escape, (FILE)); \ 431 break; \ 432 } \ 433 } \ 434 \ 435 fprintf ((FILE), "\"\n"); \ 436 } \ 437 while (0) 438 439 /* The routine used to output sequences of byte values. We use a special 440 version of this for most svr4 targets because doing so makes the 441 generated assembly code more compact (and thus faster to assemble) 442 as well as more readable. Note that if we find subparts of the 443 character sequence which end with NUL (and which are shorter than 444 STRING_LIMIT) we output those using ASM_OUTPUT_LIMITED_STRING. */ 445 446 #undef ASM_OUTPUT_ASCII 447 #define ASM_OUTPUT_ASCII(FILE, STR, LENGTH) \ 448 do \ 449 { \ 450 register const unsigned char *_ascii_bytes = \ 451 (const unsigned char *) (STR); \ 452 register const unsigned char *limit = _ascii_bytes + (LENGTH); \ 453 register unsigned bytes_in_chunk = 0; \ 454 \ 455 for (; _ascii_bytes < limit; _ascii_bytes++) \ 456 { \ 457 register const unsigned char *p; \ 458 \ 459 if (bytes_in_chunk >= 60) \ 460 { \ 461 fprintf ((FILE), "\"\n"); \ 462 bytes_in_chunk = 0; \ 463 } \ 464 \ 465 for (p = _ascii_bytes; p < limit && *p != '\0'; p++) \ 466 continue; \ 467 \ 468 if (p < limit && (p - _ascii_bytes) <= (long)STRING_LIMIT) \ 469 { \ 470 if (bytes_in_chunk > 0) \ 471 { \ 472 fprintf ((FILE), "\"\n"); \ 473 bytes_in_chunk = 0; \ 474 } \ 475 \ 476 ASM_OUTPUT_LIMITED_STRING ((FILE), _ascii_bytes); \ 477 _ascii_bytes = p; \ 478 } \ 479 else \ 480 { \ 481 register int escape; \ 482 register unsigned ch; \ 483 \ 484 if (bytes_in_chunk == 0) \ 485 fprintf ((FILE), "%s\"", ASCII_DATA_ASM_OP); \ 486 \ 487 switch (escape = ESCAPES[ch = *_ascii_bytes]) \ 488 { \ 489 case 0: \ 490 putc (ch, (FILE)); \ 491 bytes_in_chunk++; \ 492 break; \ 493 case 1: \ 494 fprintf ((FILE), "\\%03o", ch); \ 495 bytes_in_chunk += 4; \ 496 break; \ 497 default: \ 498 putc ('\\', (FILE)); \ 499 putc (escape, (FILE)); \ 500 bytes_in_chunk += 2; \ 501 break; \ 502 } \ 503 } \ 504 } \ 505 \ 506 if (bytes_in_chunk > 0) \ 507 fprintf ((FILE), "\"\n"); \ 508 } \ 509 while (0) 510