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, 2003 Free Software Foundation, Inc.
   4
   5    This file is part of GCC.
   6
   7    GCC is free software; you can redistribute it and/or modify it
   8    under the terms of the GNU General Public License as published
   9    by the Free Software Foundation; either version 2, or (at your
  10    option) any later version.
  11
  12    GCC is distributed in the hope that it will be useful, but WITHOUT
  13    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  15    License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with GCC; see the file COPYING.  If not, write to the
  19    Free Software Foundation, 59 Temple Place - Suite 330, Boston,
  20    MA 02111-1307, USA.  */
  21
  22 #define TARGET_OBJECT_FORMAT OBJECT_XCOFF
  23
  24 /* The RS/6000 uses the XCOFF format.  */
  25 #define XCOFF_DEBUGGING_INFO 1
  26
  27 /* Define if the object format being used is COFF or a superset.  */
  28 #define OBJECT_FORMAT_COFF
  29
  30 /* Define the magic numbers that we recognize as COFF.
  31
  32     AIX 4.3 adds U803XTOCMAGIC (0757) for 64-bit objects and AIX V5 adds
  33     U64_TOCMAGIC (0767), but collect2.c does not include files in the
  34     correct order to conditionally define the symbolic name in this macro.
  35
  36     The AIX linker accepts import/export files as object files,
  37     so accept "#!" (0x2321) magic number.  */
  38 #define MY_ISCOFF(magic) \
  39   ((magic) == U802WRMAGIC || (magic) == U802ROMAGIC \
  40    || (magic) == U802TOCMAGIC || (magic) == 0757 || (magic) == 0767 \
  41    || (magic) == 0x2321)
  42
  43 /* We don't have GAS for the RS/6000 yet, so don't write out special
  44     .stabs in cc1plus.  */
  45
  46 #define FASCIST_ASSEMBLER
  47
  48 /* We define this to prevent the name mangler from putting dollar signs into
  49    function names.  */
  50
  51 #define NO_DOLLAR_IN_LABEL
  52
  53 /* We define this to 0 so that gcc will never accept a dollar sign in a
  54    variable name.  This is needed because the AIX assembler will not accept
  55    dollar signs.  */
  56
  57 #define DOLLARS_IN_IDENTIFIERS 0
  58
  59 /* Define the extra sections we need.  We define three: one is the read-only
  60    data section which is used for constants.  This is a csect whose name is
  61    derived from the name of the input file.  The second is for initialized
  62    global variables.  This is a csect whose name is that of the variable.
  63    The third is the TOC.  */
  64
  65 #define EXTRA_SECTIONS \
  66    read_only_data, private_data, read_only_private_data, toc, bss
  67
  68 /* Define the routines to implement these extra sections.
  69    BIGGEST_ALIGNMENT is 64, so align the sections that much.  */
  70
  71 #define EXTRA_SECTION_FUNCTIONS                         \
  72                                                         \
  73 void                                                    \
  74 read_only_data_section ()                               \
  75 {                                                       \
  76   if (in_section != read_only_data)                     \
  77     {                                                   \
  78       fprintf (asm_out_file, "\t.csect %s[RO],3\n",     \
  79                xcoff_read_only_section_name);           \
  80       in_section = read_only_data;                      \
  81     }                                                   \
  82 }                                                       \
  83                                                         \
  84 void                                                    \
  85 private_data_section ()                                 \
  86 {                                                       \
  87   if (in_section != private_data)                       \
  88     {                                                   \
  89       fprintf (asm_out_file, "\t.csect %s[RW],3\n",     \
  90                xcoff_private_data_section_name);        \
  91       in_section = private_data;                        \
  92     }                                                   \
  93 }                                                       \
  94                                                         \
  95 void                                                    \
  96 read_only_private_data_section ()                       \
  97 {                                                       \
  98   if (in_section != read_only_private_data)             \
  99     {                                                   \
 100       fprintf (asm_out_file, "\t.csect %s[RO],3\n",     \
 101                xcoff_private_data_section_name);        \
 102       in_section = read_only_private_data;              \
 103     }                                                   \
 104 }                                                       \
 105                                                         \
 106 void                                                    \
 107 toc_section ()                                          \
 108 {                                                       \
 109   if (TARGET_MINIMAL_TOC)                               \
 110     {                                                   \
 111       /* toc_section is always called at least once from ASM_FILE_START, \
 112          so this is guaranteed to always be defined once and only once   \
 113          in each file.  */                                               \
 114       if (! toc_initialized)                            \
 115         {                                               \
 116           fputs ("\t.toc\nLCTOC..1:\n", asm_out_file);  \
 117           fputs ("\t.tc toc_table[TC],toc_table[RW]\n", asm_out_file); \
 118           toc_initialized = 1;                          \
 119         }                                               \
 120                                                         \
 121       if (in_section != toc)                            \
 122         fprintf (asm_out_file, "\t.csect toc_table[RW]%s\n",    \
 123                  (TARGET_32BIT ? "" : ",3"));           \
 124     }                                                   \
 125   else                                                  \
 126     {                                                   \
 127       if (in_section != toc)                            \
 128         fputs ("\t.toc\n", asm_out_file);               \
 129     }                                                   \
 130   in_section = toc;                                     \
 131 }
 132
 133 /* Define the name of our readonly data section.  */
 134
 135 #define READONLY_DATA_SECTION read_only_data_section
 136
 137 /* Return nonzero if this entry is to be written into the constant
 138    pool in a special way.  We do so if this is a SYMBOL_REF, LABEL_REF
 139    or a CONST containing one of them.  If -mfp-in-toc (the default),
 140    we also do this for floating-point constants.  We actually can only
 141    do this if the FP formats of the target and host machines are the
 142    same, but we can't check that since not every file that uses
 143    GO_IF_LEGITIMATE_ADDRESS_P includes real.h.  We also do this when
 144    we can write the entry into the TOC and the entry is not larger
 145    than a TOC entry.  */
 146
 147 #define ASM_OUTPUT_SPECIAL_POOL_ENTRY_P(X, MODE)                        \
 148   (TARGET_TOC                                                           \
 149    && (GET_CODE (X) == SYMBOL_REF                                       \
 150        || (GET_CODE (X) == CONST && GET_CODE (XEXP (X, 0)) == PLUS      \
 151            && GET_CODE (XEXP (XEXP (X, 0), 0)) == SYMBOL_REF)           \
 152        || GET_CODE (X) == LABEL_REF                                     \
 153        || (GET_CODE (X) == CONST_INT                                    \
 154            && GET_MODE_BITSIZE (MODE) <= GET_MODE_BITSIZE (Pmode))      \
 155        || (GET_CODE (X) == CONST_DOUBLE                                 \
 156            && (TARGET_POWERPC64                                         \
 157                || TARGET_MINIMAL_TOC                                    \
 158                || (GET_MODE_CLASS (GET_MODE (X)) == MODE_FLOAT          \
 159                    && ! TARGET_NO_FP_IN_TOC)))))
 160
 161 #define TARGET_ASM_GLOBALIZE_LABEL  rs6000_xcoff_asm_globalize_label
 162 #define TARGET_ASM_NAMED_SECTION  rs6000_xcoff_asm_named_section
 163 #define TARGET_ASM_SELECT_SECTION  rs6000_xcoff_select_section
 164 #define TARGET_ASM_SELECT_RTX_SECTION  rs6000_xcoff_select_rtx_section
 165 #define TARGET_ASM_UNIQUE_SECTION  rs6000_xcoff_unique_section
 166 #define TARGET_STRIP_NAME_ENCODING  rs6000_xcoff_strip_name_encoding
 167 #define TARGET_SECTION_TYPE_FLAGS  rs6000_xcoff_section_type_flags
 168
 169 /* FP save and restore routines.  */
 170 #define SAVE_FP_PREFIX "._savef"
 171 #define SAVE_FP_SUFFIX ""
 172 #define RESTORE_FP_PREFIX "._restf"
 173 #define RESTORE_FP_SUFFIX ""
 174
 175 /* Function name to call to do profiling.  */
 176 #undef  RS6000_MCOUNT
 177 #define RS6000_MCOUNT ".__mcount"
 178
 179 /* Function names to call to do floating point truncation.  */
 180
 181 #undef  RS6000_ITRUNC
 182 #define RS6000_ITRUNC "__itrunc"
 183 #undef  RS6000_UITRUNC
 184 #define RS6000_UITRUNC "__uitrunc"
 185
 186 /* This outputs NAME to FILE up to the first null or '['.  */
 187
 188 #define RS6000_OUTPUT_BASENAME(FILE, NAME) \
 189   assemble_name ((FILE), (*targetm.strip_name_encoding) (NAME))
 190
 191 /* This is how to output the definition of a user-level label named NAME,
 192    such as the label on a static function or variable NAME.  */
 193
 194 #define ASM_OUTPUT_LABEL(FILE,NAME)     \
 195   do { RS6000_OUTPUT_BASENAME (FILE, NAME); fputs (":\n", FILE); } while (0)
 196
 197 /* This is how to output a command to make the user-level label named NAME
 198    defined for reference from other files.  */
 199
 200 /* Globalizing directive for a label.  */
 201 #define GLOBAL_ASM_OP "\t.globl "
 202
 203 /* Output at beginning of assembler file.
 204
 205    Initialize the section names for the RS/6000 at this point.
 206
 207    Specify filename, including full path, to assembler.
 208
 209    We want to go into the TOC section so at least one .toc will be emitted.
 210    Also, in order to output proper .bs/.es pairs, we need at least one static
 211    [RW] section emitted.
 212
 213    Finally, declare mcount when profiling to make the assembler happy.  */
 214
 215 #define ASM_FILE_START(FILE)                                    \
 216 {                                                               \
 217   rs6000_gen_section_name (&xcoff_bss_section_name,             \
 218                            main_input_filename, ".bss_");       \
 219   rs6000_gen_section_name (&xcoff_private_data_section_name,    \
 220                            main_input_filename, ".rw_");        \
 221   rs6000_gen_section_name (&xcoff_read_only_section_name,       \
 222                            main_input_filename, ".ro_");        \
 223                                                                 \
 224   fputs ("\t.file\t", FILE);                                    \
 225   output_quoted_string (FILE, main_input_filename);             \
 226   fputc ('\n', FILE);                                           \
 227   toc_section ();                                               \
 228   if (write_symbols != NO_DEBUG)                                \
 229     private_data_section ();                                    \
 230   text_section ();                                              \
 231   if (profile_flag)                                             \
 232     fprintf (FILE, "\t.extern %s\n", RS6000_MCOUNT);            \
 233   rs6000_file_start (FILE, TARGET_CPU_DEFAULT);                 \
 234 }
 235
 236 /* Output at end of assembler file.
 237
 238    On the RS/6000, referencing data should automatically pull in text.  */
 239
 240 #define ASM_FILE_END(FILE)                                      \
 241 {                                                               \
 242   text_section ();                                              \
 243   fputs ("_section_.text:\n", FILE);                            \
 244   data_section ();                                              \
 245   fputs (TARGET_32BIT                                           \
 246          ? "\t.long _section_.text\n" : "\t.llong _section_.text\n", FILE); \
 247 }
 248
 249 /* This macro produces the initial definition of a function name.
 250    On the RS/6000, we need to place an extra '.' in the function name and
 251    output the function descriptor.
 252
 253    The csect for the function will have already been created by the
 254    `text_section' call previously done.  We do have to go back to that
 255    csect, however.
 256
 257    The third and fourth parameters to the .function pseudo-op (16 and 044)
 258    are placeholders which no longer have any use.  */
 259
 260 #define ASM_DECLARE_FUNCTION_NAME(FILE,NAME,DECL)               \
 261 { rtx sym_ref = XEXP (DECL_RTL (DECL), 0);                      \
 262   if (TREE_PUBLIC (DECL))                                       \
 263     {                                                           \
 264       if (!RS6000_WEAK || !DECL_WEAK (decl))                    \
 265         {                                                       \
 266           fputs ("\t.globl .", FILE);                           \
 267           RS6000_OUTPUT_BASENAME (FILE, NAME);                  \
 268           putc ('\n', FILE);                                    \
 269         }                                                       \
 270     }                                                           \
 271   else                                                          \
 272     {                                                           \
 273       fputs ("\t.lglobl .", FILE);                              \
 274       RS6000_OUTPUT_BASENAME (FILE, NAME);                      \
 275       putc ('\n', FILE);                                        \
 276     }                                                           \
 277   fputs ("\t.csect ", FILE);                                    \
 278   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 279   fputs (TARGET_32BIT ? "[DS]\n" : "[DS],3\n", FILE);           \
 280   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 281   fputs (":\n", FILE);                                          \
 282   fputs (TARGET_32BIT ? "\t.long ." : "\t.llong .", FILE);      \
 283   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 284   fputs (", TOC[tc0], 0\n", FILE);                              \
 285   in_section = no_section;                                      \
 286   function_section(DECL);                                       \
 287   putc ('.', FILE);                                             \
 288   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 289   fputs (":\n", FILE);                                          \
 290   if (write_symbols != NO_DEBUG)                                \
 291     xcoffout_declare_function (FILE, DECL, NAME);               \
 292 }
 293
 294 /* Output a reference to SYM on FILE.  */
 295
 296 #define ASM_OUTPUT_SYMBOL_REF(FILE, SYM) \
 297   rs6000_output_symbol_ref (FILE, SYM)
 298
 299 /* This says how to output an external.  */
 300
 301 #undef  ASM_OUTPUT_EXTERNAL
 302 #define ASM_OUTPUT_EXTERNAL(FILE, DECL, NAME)                           \
 303 { rtx _symref = XEXP (DECL_RTL (DECL), 0);                              \
 304   if ((TREE_CODE (DECL) == VAR_DECL                                     \
 305        || TREE_CODE (DECL) == FUNCTION_DECL)                            \
 306       && (NAME)[strlen (NAME) - 1] != ']')                              \
 307     {                                                                   \
 308       XSTR (_symref, 0) = concat (XSTR (_symref, 0),                    \
 309                                   (TREE_CODE (DECL) == FUNCTION_DECL    \
 310                                    ? "[DS]" : "[RW]"),                  \
 311                                   NULL);                                \
 312     }                                                                   \
 313 }
 314
 315 /* This is how to output an internal label prefix.  rs6000.c uses this
 316    when generating traceback tables.  */
 317
 318 #define ASM_OUTPUT_INTERNAL_LABEL_PREFIX(FILE,PREFIX)   \
 319   fprintf (FILE, "%s..", PREFIX)
 320
 321 /* This is how to output a label for a jump table.  Arguments are the same as
 322    for (*targetm.asm_out.internal_label), except the insn for the jump table is
 323    passed.  */
 324
 325 #define ASM_OUTPUT_CASE_LABEL(FILE,PREFIX,NUM,TABLEINSN)        \
 326 { ASM_OUTPUT_ALIGN (FILE, 2); (*targetm.asm_out.internal_label) (FILE, PREFIX, NUM); }
 327
 328 /* This is how to store into the string LABEL
 329    the symbol_ref name of an internal numbered label where
 330    PREFIX is the class of label and NUM is the number within the class.
 331    This is suitable for output with `assemble_name'.  */
 332
 333 #define ASM_GENERATE_INTERNAL_LABEL(LABEL,PREFIX,NUM)   \
 334   sprintf (LABEL, "*%s..%u", (PREFIX), (unsigned) (NUM))
 335
 336 /* This is how to output an assembler line to define N characters starting
 337    at P to FILE.  */
 338
 339 #define ASM_OUTPUT_ASCII(FILE, P, N)  output_ascii ((FILE), (P), (N))
 340
 341 /* This is how to advance the location counter by SIZE bytes.  */
 342
 343 #define SKIP_ASM_OP "\t.space "
 344
 345 #define ASM_OUTPUT_SKIP(FILE,SIZE)  \
 346   fprintf (FILE, "%s"HOST_WIDE_INT_PRINT_UNSIGNED"\n", SKIP_ASM_OP, (SIZE))
 347
 348 /* This says how to output an assembler line
 349    to define a global common symbol.  */
 350
 351 #define COMMON_ASM_OP "\t.comm "
 352
 353 #define ASM_OUTPUT_ALIGNED_COMMON(FILE, NAME, SIZE, ALIGN)      \
 354   do { fputs (COMMON_ASM_OP, (FILE));                   \
 355        RS6000_OUTPUT_BASENAME ((FILE), (NAME));         \
 356        if ((ALIGN) > 32)                                \
 357          fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%u\n", (SIZE), \
 358                   exact_log2 ((ALIGN) / BITS_PER_UNIT)); \
 359        else if ((SIZE) > 4)                             \
 360          fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",3\n", (SIZE)); \
 361        else                                             \
 362          fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED"\n", (SIZE)); \
 363   } while (0)
 364
 365 /* This says how to output an assembler line
 366    to define a local common symbol.
 367    Alignment cannot be specified, but we can try to maintain
 368    alignment after preceding TOC section if it was aligned
 369    for 64-bit mode.  */
 370
 371 #define LOCAL_COMMON_ASM_OP "\t.lcomm "
 372
 373 #define ASM_OUTPUT_LOCAL(FILE, NAME, SIZE, ROUNDED)     \
 374   do { fputs (LOCAL_COMMON_ASM_OP, (FILE));             \
 375        RS6000_OUTPUT_BASENAME ((FILE), (NAME));         \
 376        fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%s\n", \
 377                 (TARGET_32BIT ? (SIZE) : (ROUNDED)),    \
 378                 xcoff_bss_section_name);                \
 379      } while (0)
 380
 381 /* This is how we tell the assembler that two symbols have the same value.  */
 382 #define SET_ASM_OP "\t.set "
 383
 384 /* This is how we tell the assembler to equate two values.  */
 385 #define ASM_OUTPUT_DEF(FILE,LABEL1,LABEL2)                              \
 386  do {   fprintf ((FILE), "%s", SET_ASM_OP);                             \
 387         RS6000_OUTPUT_BASENAME (FILE, LABEL1);                          \
 388         fprintf (FILE, ",");                                            \
 389         RS6000_OUTPUT_BASENAME (FILE, LABEL2);                          \
 390         fprintf (FILE, "\n");                                           \
 391   } while (0)
 392
 393 /* Used by rs6000_assemble_integer, among others.  */
 394 #define DOUBLE_INT_ASM_OP "\t.llong\t"
 395
 396 /* Output before instructions.  */
 397 #define TEXT_SECTION_ASM_OP "\t.csect .text[PR]"
 398
 399 /* Output before writable data.
 400    Align entire section to BIGGEST_ALIGNMENT.  */
 401 #define DATA_SECTION_ASM_OP "\t.csect .data[RW],3"
 402
 403 /* Define the name of the section to use for the EH language specific
 404    data areas (.gcc_except_table on most other systems).  */
 405 #define TARGET_ASM_EXCEPTION_SECTION data_section
 406
 407 /* Define to prevent DWARF2 unwind info in the data section rather
 408    than in the .eh_frame section.  We do this because the AIX linker
 409    would otherwise garbage collect these sections.  */
 410 #define EH_FRAME_IN_DATA_SECTION 1