gcc/config/rs6000/xcoff.h

   1 /* Definitions of target machine for GNU compiler,
   2    for some generic XCOFF file format
   3    Copyright (C) 2001, 2002 Free Software Foundation, Inc.
   4
   5 This file is part of GNU CC.
   6
   7 GNU CC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU CC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU CC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22
  23 #define TARGET_OBJECT_FORMAT OBJECT_XCOFF
  24
  25 /* The RS/6000 uses the XCOFF format.  */
  26 #define XCOFF_DEBUGGING_INFO 1
  27
  28 /* Define if the object format being used is COFF or a superset.  */
  29 #define OBJECT_FORMAT_COFF
  30
  31 /* Define the magic numbers that we recognize as COFF.
  32
  33     AIX 4.3 adds U803XTOCMAGIC (0757) for 64-bit objects and AIX V5 adds
  34     U64_TOCMAGIC (0767), but collect2.c does not include files in the
  35     correct order to conditionally define the symbolic name in this macro.
  36
  37     The AIX linker accepts import/export files as object files,
  38     so accept "#!" (0x2321) magic number.  */
  39 #define MY_ISCOFF(magic) \
  40   ((magic) == U802WRMAGIC || (magic) == U802ROMAGIC \
  41    || (magic) == U802TOCMAGIC || (magic) == 0757 || (magic) == 0767 \
  42    || (magic) == 0x2321)
  43
  44 /* We don't have GAS for the RS/6000 yet, so don't write out special
  45     .stabs in cc1plus.  */
  46
  47 #define FASCIST_ASSEMBLER
  48
  49 /* We define this to prevent the name mangler from putting dollar signs into
  50    function names.  */
  51
  52 #define NO_DOLLAR_IN_LABEL
  53
  54 /* We define this to 0 so that gcc will never accept a dollar sign in a
  55    variable name.  This is needed because the AIX assembler will not accept
  56    dollar signs.  */
  57
  58 #define DOLLARS_IN_IDENTIFIERS 0
  59
  60 /* Define the extra sections we need.  We define three: one is the read-only
  61    data section which is used for constants.  This is a csect whose name is
  62    derived from the name of the input file.  The second is for initialized
  63    global variables.  This is a csect whose name is that of the variable.
  64    The third is the TOC.  */
  65
  66 #define EXTRA_SECTIONS \
  67    read_only_data, private_data, read_only_private_data, toc, bss
  68
  69 /* Define the routines to implement these extra sections.
  70    BIGGEST_ALIGNMENT is 64, so align the sections that much.  */
  71
  72 #define EXTRA_SECTION_FUNCTIONS                         \
  73                                                         \
  74 void                                                    \
  75 read_only_data_section ()                               \
  76 {                                                       \
  77   if (in_section != read_only_data)                     \
  78     {                                                   \
  79       fprintf (asm_out_file, "\t.csect %s[RO],3\n",     \
  80                xcoff_read_only_section_name);           \
  81       in_section = read_only_data;                      \
  82     }                                                   \
  83 }                                                       \
  84                                                         \
  85 void                                                    \
  86 private_data_section ()                                 \
  87 {                                                       \
  88   if (in_section != private_data)                       \
  89     {                                                   \
  90       fprintf (asm_out_file, "\t.csect %s[RW],3\n",     \
  91                xcoff_private_data_section_name);        \
  92       in_section = private_data;                        \
  93     }                                                   \
  94 }                                                       \
  95                                                         \
  96 void                                                    \
  97 read_only_private_data_section ()                       \
  98 {                                                       \
  99   if (in_section != read_only_private_data)             \
 100     {                                                   \
 101       fprintf (asm_out_file, "\t.csect %s[RO],3\n",     \
 102                xcoff_private_data_section_name);        \
 103       in_section = read_only_private_data;              \
 104     }                                                   \
 105 }                                                       \
 106                                                         \
 107 void                                                    \
 108 toc_section ()                                          \
 109 {                                                       \
 110   if (TARGET_MINIMAL_TOC)                               \
 111     {                                                   \
 112       /* toc_section is always called at least once from ASM_FILE_START, \
 113          so this is guaranteed to always be defined once and only once   \
 114          in each file.  */                                               \
 115       if (! toc_initialized)                            \
 116         {                                               \
 117           fputs ("\t.toc\nLCTOC..1:\n", asm_out_file);  \
 118           fputs ("\t.tc toc_table[TC],toc_table[RW]\n", asm_out_file); \
 119           toc_initialized = 1;                          \
 120         }                                               \
 121                                                         \
 122       if (in_section != toc)                            \
 123         fprintf (asm_out_file, "\t.csect toc_table[RW]%s\n",    \
 124                  (TARGET_32BIT ? "" : ",3"));           \
 125     }                                                   \
 126   else                                                  \
 127     {                                                   \
 128       if (in_section != toc)                            \
 129         fputs ("\t.toc\n", asm_out_file);               \
 130     }                                                   \
 131   in_section = toc;                                     \
 132 }
 133
 134 /* Define the name of our readonly data section.  */
 135
 136 #define READONLY_DATA_SECTION read_only_data_section
 137
 138 /* Return nonzero if this entry is to be written into the constant
 139    pool in a special way.  We do so if this is a SYMBOL_REF, LABEL_REF
 140    or a CONST containing one of them.  If -mfp-in-toc (the default),
 141    we also do this for floating-point constants.  We actually can only
 142    do this if the FP formats of the target and host machines are the
 143    same, but we can't check that since not every file that uses
 144    GO_IF_LEGITIMATE_ADDRESS_P includes real.h.  We also do this when
 145    we can write the entry into the TOC and the entry is not larger
 146    than a TOC entry.  */
 147
 148 #define ASM_OUTPUT_SPECIAL_POOL_ENTRY_P(X, MODE)                        \
 149   (TARGET_TOC                                                           \
 150    && (GET_CODE (X) == SYMBOL_REF                                       \
 151        || (GET_CODE (X) == CONST && GET_CODE (XEXP (X, 0)) == PLUS      \
 152            && GET_CODE (XEXP (XEXP (X, 0), 0)) == SYMBOL_REF)           \
 153        || GET_CODE (X) == LABEL_REF                                     \
 154        || (GET_CODE (X) == CONST_INT                                    \
 155            && GET_MODE_BITSIZE (MODE) <= GET_MODE_BITSIZE (Pmode))      \
 156        || (GET_CODE (X) == CONST_DOUBLE                                 \
 157            && (TARGET_POWERPC64                                         \
 158                || TARGET_MINIMAL_TOC                                    \
 159                || (GET_MODE_CLASS (GET_MODE (X)) == MODE_FLOAT          \
 160                    && ! TARGET_NO_FP_IN_TOC)))))
 161
 162 #define TARGET_ASM_GLOBALIZE_LABEL  rs6000_xcoff_asm_globalize_label
 163 #define TARGET_ASM_NAMED_SECTION  rs6000_xcoff_asm_named_section
 164 #define TARGET_ASM_SELECT_SECTION  rs6000_xcoff_select_section
 165 #define TARGET_ASM_SELECT_RTX_SECTION  rs6000_xcoff_select_rtx_section
 166 #define TARGET_ASM_UNIQUE_SECTION  rs6000_xcoff_unique_section
 167 #define TARGET_ENCODE_SECTION_INFO  rs6000_xcoff_encode_section_info
 168 #define TARGET_STRIP_NAME_ENCODING  rs6000_xcoff_strip_name_encoding
 169 #define TARGET_SECTION_TYPE_FLAGS  rs6000_xcoff_section_type_flags
 170
 171 /* FP save and restore routines.  */
 172 #define SAVE_FP_PREFIX "._savef"
 173 #define SAVE_FP_SUFFIX ""
 174 #define RESTORE_FP_PREFIX "._restf"
 175 #define RESTORE_FP_SUFFIX ""
 176
 177 /* Function name to call to do profiling.  */
 178 #undef RS6000_MCOUNT
 179 #define RS6000_MCOUNT ".__mcount"
 180
 181 /* Function names to call to do floating point truncation.  */
 182
 183 #undef RS6000_ITRUNC
 184 #define RS6000_ITRUNC "__itrunc"
 185 #undef RS6000_UITRUNC
 186 #define RS6000_UITRUNC "__uitrunc"
 187
 188 /* This outputs NAME to FILE up to the first null or '['.  */
 189
 190 #define RS6000_OUTPUT_BASENAME(FILE, NAME) \
 191   assemble_name ((FILE), (*targetm.strip_name_encoding) (NAME))
 192
 193 /* This is how to output the definition of a user-level label named NAME,
 194    such as the label on a static function or variable NAME.  */
 195
 196 #define ASM_OUTPUT_LABEL(FILE,NAME)     \
 197   do { RS6000_OUTPUT_BASENAME (FILE, NAME); fputs (":\n", FILE); } while (0)
 198
 199 /* This is how to output a command to make the user-level label named NAME
 200    defined for reference from other files.  */
 201
 202 /* Globalizing directive for a label.  */
 203 #define GLOBAL_ASM_OP "\t.globl "
 204
 205 /* Output at beginning of assembler file.
 206
 207    Initialize the section names for the RS/6000 at this point.
 208
 209    Specify filename, including full path, to assembler.
 210
 211    We want to go into the TOC section so at least one .toc will be emitted.
 212    Also, in order to output proper .bs/.es pairs, we need at least one static
 213    [RW] section emitted.
 214
 215    Finally, declare mcount when profiling to make the assembler happy.  */
 216
 217 #define ASM_FILE_START(FILE)                                    \
 218 {                                                               \
 219   rs6000_gen_section_name (&xcoff_bss_section_name,             \
 220                            main_input_filename, ".bss_");       \
 221   rs6000_gen_section_name (&xcoff_private_data_section_name,    \
 222                            main_input_filename, ".rw_");        \
 223   rs6000_gen_section_name (&xcoff_read_only_section_name,       \
 224                            main_input_filename, ".ro_");        \
 225                                                                 \
 226   fputs ("\t.file\t", FILE);                                    \
 227   output_quoted_string (FILE, main_input_filename);             \
 228   fputc ('\n', FILE);                                           \
 229   if (TARGET_64BIT)                                             \
 230     fputs ("\t.machine\t\"ppc64\"\n", FILE);                    \
 231   toc_section ();                                               \
 232   if (write_symbols != NO_DEBUG)                                \
 233     private_data_section ();                                    \
 234   text_section ();                                              \
 235   if (profile_flag)                                             \
 236     fprintf (FILE, "\t.extern %s\n", RS6000_MCOUNT);            \
 237   rs6000_file_start (FILE, TARGET_CPU_DEFAULT);                 \
 238 }
 239
 240 /* Output at end of assembler file.
 241
 242    On the RS/6000, referencing data should automatically pull in text.  */
 243
 244 #define ASM_FILE_END(FILE)                                      \
 245 {                                                               \
 246   text_section ();                                              \
 247   fputs ("_section_.text:\n", FILE);                            \
 248   data_section ();                                              \
 249   fputs (TARGET_32BIT                                           \
 250          ? "\t.long _section_.text\n" : "\t.llong _section_.text\n", FILE); \
 251 }
 252
 253 /* This macro produces the initial definition of a function name.
 254    On the RS/6000, we need to place an extra '.' in the function name and
 255    output the function descriptor.
 256
 257    The csect for the function will have already been created by the
 258    `text_section' call previously done.  We do have to go back to that
 259    csect, however.
 260
 261    We also record that the function exists in the current compilation
 262    unit, reachable by short branch, by setting SYMBOL_REF_FLAG.
 263
 264    The third and fourth parameters to the .function pseudo-op (16 and 044)
 265    are placeholders which no longer have any use.  */
 266
 267 #define ASM_DECLARE_FUNCTION_NAME(FILE,NAME,DECL)               \
 268 { rtx sym_ref = XEXP (DECL_RTL (DECL), 0);                      \
 269   if ((*targetm.binds_local_p) (DECL))                          \
 270     SYMBOL_REF_FLAG (sym_ref) = 1;                              \
 271   if (TREE_PUBLIC (DECL))                                       \
 272     {                                                           \
 273       if (!RS6000_WEAK || !DECL_WEAK (decl))                    \
 274         {                                                       \
 275           fputs ("\t.globl .", FILE);                           \
 276           RS6000_OUTPUT_BASENAME (FILE, NAME);                  \
 277           putc ('\n', FILE);                                    \
 278         }                                                       \
 279     }                                                           \
 280   else                                                          \
 281     {                                                           \
 282       fputs ("\t.lglobl .", FILE);                              \
 283       RS6000_OUTPUT_BASENAME (FILE, NAME);                      \
 284       putc ('\n', FILE);                                        \
 285     }                                                           \
 286   fputs ("\t.csect ", FILE);                                    \
 287   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 288   fputs (TARGET_32BIT ? "[DS]\n" : "[DS],3\n", FILE);           \
 289   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 290   fputs (":\n", FILE);                                          \
 291   fputs (TARGET_32BIT ? "\t.long ." : "\t.llong .", FILE);      \
 292   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 293   fputs (", TOC[tc0], 0\n", FILE);                              \
 294   in_section = no_section;                                      \
 295   function_section(DECL);                                       \
 296   putc ('.', FILE);                                             \
 297   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 298   fputs (":\n", FILE);                                          \
 299   if (write_symbols != NO_DEBUG)                                \
 300     xcoffout_declare_function (FILE, DECL, NAME);               \
 301 }
 302
 303 /* Output a reference to SYM on FILE.  */
 304
 305 #define ASM_OUTPUT_SYMBOL_REF(FILE, SYM) \
 306   rs6000_output_symbol_ref (FILE, SYM)
 307
 308 /* This says how to output an external.  */
 309
 310 #undef ASM_OUTPUT_EXTERNAL
 311 #define ASM_OUTPUT_EXTERNAL(FILE, DECL, NAME)                           \
 312 { rtx _symref = XEXP (DECL_RTL (DECL), 0);                              \
 313   if ((TREE_CODE (DECL) == VAR_DECL                                     \
 314        || TREE_CODE (DECL) == FUNCTION_DECL)                            \
 315       && (NAME)[strlen (NAME) - 1] != ']')                              \
 316     {                                                                   \
 317       XSTR (_symref, 0) = concat (XSTR (_symref, 0),                    \
 318                                   (TREE_CODE (DECL) == FUNCTION_DECL    \
 319                                    ? "[DS]" : "[RW]"),                  \
 320                                   NULL);                                \
 321     }                                                                   \
 322 }
 323
 324 /* This is how to output an internal label prefix.  rs6000.c uses this
 325    when generating traceback tables.  */
 326
 327 #define ASM_OUTPUT_INTERNAL_LABEL_PREFIX(FILE,PREFIX)   \
 328   fprintf (FILE, "%s..", PREFIX)
 329
 330 /* This is how to output a label for a jump table.  Arguments are the same as
 331    for (*targetm.asm_out.internal_label), except the insn for the jump table is
 332    passed.  */
 333
 334 #define ASM_OUTPUT_CASE_LABEL(FILE,PREFIX,NUM,TABLEINSN)        \
 335 { ASM_OUTPUT_ALIGN (FILE, 2); (*targetm.asm_out.internal_label) (FILE, PREFIX, NUM); }
 336
 337 /* This is how to store into the string LABEL
 338    the symbol_ref name of an internal numbered label where
 339    PREFIX is the class of label and NUM is the number within the class.
 340    This is suitable for output with `assemble_name'.  */
 341
 342 #define ASM_GENERATE_INTERNAL_LABEL(LABEL,PREFIX,NUM)   \
 343   sprintf (LABEL, "*%s..%u", (PREFIX), (unsigned) (NUM))
 344
 345 /* This is how to output an assembler line to define N characters starting
 346    at P to FILE.  */
 347
 348 #define ASM_OUTPUT_ASCII(FILE, P, N)  output_ascii ((FILE), (P), (N))
 349
 350 /* This is how to advance the location counter by SIZE bytes.  */
 351
 352 #define SKIP_ASM_OP "\t.space "
 353
 354 #define ASM_OUTPUT_SKIP(FILE,SIZE)  \
 355   fprintf (FILE, "%s%u\n", SKIP_ASM_OP, (SIZE))
 356
 357 /* This says how to output an assembler line
 358    to define a global common symbol.  */
 359
 360 #define COMMON_ASM_OP "\t.comm "
 361
 362 #define ASM_OUTPUT_ALIGNED_COMMON(FILE, NAME, SIZE, ALIGN)      \
 363   do { fputs (COMMON_ASM_OP, (FILE));                   \
 364        RS6000_OUTPUT_BASENAME ((FILE), (NAME));         \
 365        if ((ALIGN) > 32)                                \
 366          fprintf ((FILE), ",%u,%u\n", (SIZE),           \
 367                   exact_log2 ((ALIGN) / BITS_PER_UNIT)); \
 368        else if ((SIZE) > 4)                             \
 369          fprintf ((FILE), ",%u,3\n", (SIZE));           \
 370        else                                             \
 371          fprintf ((FILE), ",%u\n", (SIZE));             \
 372   } while (0)
 373
 374 /* This says how to output an assembler line
 375    to define a local common symbol.
 376    Alignment cannot be specified, but we can try to maintain
 377    alignment after preceding TOC section if it was aligned
 378    for 64-bit mode.  */
 379
 380 #define LOCAL_COMMON_ASM_OP "\t.lcomm "
 381
 382 #define ASM_OUTPUT_LOCAL(FILE, NAME, SIZE, ROUNDED)     \
 383   do { fputs (LOCAL_COMMON_ASM_OP, (FILE));             \
 384        RS6000_OUTPUT_BASENAME ((FILE), (NAME));         \
 385        fprintf ((FILE), ",%u,%s\n", (TARGET_32BIT ? (SIZE) : (ROUNDED)), \
 386                 xcoff_bss_section_name);                \
 387      } while (0)
 388
 389 /* This is how we tell the assembler that two symbols have the same value.  */
 390 #define SET_ASM_OP "\t.set "
 391
 392 /* This is how we tell the assembler to equate two values.  */
 393 #define ASM_OUTPUT_DEF(FILE,LABEL1,LABEL2)                              \
 394  do {   fprintf ((FILE), "%s", SET_ASM_OP);                             \
 395         RS6000_OUTPUT_BASENAME (FILE, LABEL1);                          \
 396         fprintf (FILE, ",");                                            \
 397         RS6000_OUTPUT_BASENAME (FILE, LABEL2);                          \
 398         fprintf (FILE, "\n");                                           \
 399   } while (0)
 400
 401 /* Used by rs6000_assemble_integer, among others.  */
 402 #define DOUBLE_INT_ASM_OP "\t.llong\t"
 403
 404 /* Output before instructions.  */
 405 #define TEXT_SECTION_ASM_OP "\t.csect .text[PR]"
 406
 407 /* Output before writable data.
 408    Align entire section to BIGGEST_ALIGNMENT.  */
 409 #define DATA_SECTION_ASM_OP "\t.csect .data[RW],3"
 410
 411 /* Define the name of the section to use for the EH language specific
 412    data areas (.gcc_except_table on most other systems).  */
 413 #define TARGET_ASM_EXCEPTION_SECTION data_section
 414
 415 /* Define to prevent DWARF2 unwind info in the data section rather
 416    than in the .eh_frame section.  We do this because the AIX linker
 417    would otherwise garbage collect these sections.  */
 418 #define EH_FRAME_IN_DATA_SECTION 1