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, 2004 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   READ_ONLY_DATA_SECTION_FUNCTION                       \
  73   PRIVATE_DATA_SECTION_FUNCTION                         \
  74   READ_ONLY_PRIVATE_DATA_SECTION_FUNCTION               \
  75   TOC_SECTION_FUNCTION
  76
  77 #define READ_ONLY_DATA_SECTION_FUNCTION                 \
  78 void                                                    \
  79 read_only_data_section (void)                           \
  80 {                                                       \
  81   if (in_section != read_only_data)                     \
  82     {                                                   \
  83       fprintf (asm_out_file, "\t.csect %s[RO],3\n",     \
  84                xcoff_read_only_section_name);           \
  85       in_section = read_only_data;                      \
  86     }                                                   \
  87 }
  88
  89 #define PRIVATE_DATA_SECTION_FUNCTION                   \
  90 void                                                    \
  91 private_data_section (void)                             \
  92 {                                                       \
  93   if (in_section != private_data)                       \
  94     {                                                   \
  95       fprintf (asm_out_file, "\t.csect %s[RW],3\n",     \
  96                xcoff_private_data_section_name);        \
  97       in_section = private_data;                        \
  98     }                                                   \
  99 }
 100
 101 #define READ_ONLY_PRIVATE_DATA_SECTION_FUNCTION         \
 102 void                                                    \
 103 read_only_private_data_section (void)                   \
 104 {                                                       \
 105   if (in_section != read_only_private_data)             \
 106     {                                                   \
 107       fprintf (asm_out_file, "\t.csect %s[RO],3\n",     \
 108                xcoff_private_data_section_name);        \
 109       in_section = read_only_private_data;              \
 110     }                                                   \
 111 }
 112
 113 #define TOC_SECTION_FUNCTION                            \
 114 void                                                    \
 115 toc_section (void)                                      \
 116 {                                                       \
 117   if (TARGET_MINIMAL_TOC)                               \
 118     {                                                   \
 119       /* toc_section is always called at least once     \
 120          from rs6000_xcoff_file_start, so this is       \
 121          guaranteed to always be defined once and       \
 122          only once in each file.  */                    \
 123       if (! toc_initialized)                            \
 124         {                                               \
 125           fputs ("\t.toc\nLCTOC..1:\n", asm_out_file);  \
 126           fputs ("\t.tc toc_table[TC],toc_table[RW]\n", asm_out_file); \
 127           toc_initialized = 1;                          \
 128         }                                               \
 129                                                         \
 130       if (in_section != toc)                            \
 131         fprintf (asm_out_file, "\t.csect toc_table[RW]%s\n",    \
 132                  (TARGET_32BIT ? "" : ",3"));           \
 133     }                                                   \
 134   else                                                  \
 135     {                                                   \
 136       if (in_section != toc)                            \
 137         fputs ("\t.toc\n", asm_out_file);               \
 138     }                                                   \
 139   in_section = toc;                                     \
 140 }
 141
 142 /* Define the name of our readonly data section.  */
 143
 144 #define READONLY_DATA_SECTION read_only_data_section
 145
 146 /* Return nonzero if this entry is to be written into the constant
 147    pool in a special way.  We do so if this is a SYMBOL_REF, LABEL_REF
 148    or a CONST containing one of them.  If -mfp-in-toc (the default),
 149    we also do this for floating-point constants.  We actually can only
 150    do this if the FP formats of the target and host machines are the
 151    same, but we can't check that since not every file that uses
 152    GO_IF_LEGITIMATE_ADDRESS_P includes real.h.  We also do this when
 153    we can write the entry into the TOC and the entry is not larger
 154    than a TOC entry.  */
 155
 156 #define ASM_OUTPUT_SPECIAL_POOL_ENTRY_P(X, MODE)                        \
 157   (TARGET_TOC                                                           \
 158    && (GET_CODE (X) == SYMBOL_REF                                       \
 159        || (GET_CODE (X) == CONST && GET_CODE (XEXP (X, 0)) == PLUS      \
 160            && GET_CODE (XEXP (XEXP (X, 0), 0)) == SYMBOL_REF)           \
 161        || GET_CODE (X) == LABEL_REF                                     \
 162        || (GET_CODE (X) == CONST_INT                                    \
 163            && GET_MODE_BITSIZE (MODE) <= GET_MODE_BITSIZE (Pmode))      \
 164        || (GET_CODE (X) == CONST_DOUBLE                                 \
 165            && (TARGET_POWERPC64                                         \
 166                || TARGET_MINIMAL_TOC                                    \
 167                || (GET_MODE_CLASS (GET_MODE (X)) == MODE_FLOAT          \
 168                    && ! TARGET_NO_FP_IN_TOC)))))
 169
 170 #define TARGET_ASM_GLOBALIZE_LABEL  rs6000_xcoff_asm_globalize_label
 171 #define TARGET_ASM_NAMED_SECTION  rs6000_xcoff_asm_named_section
 172 #define TARGET_ASM_SELECT_SECTION  rs6000_xcoff_select_section
 173 #define TARGET_ASM_SELECT_RTX_SECTION  rs6000_xcoff_select_rtx_section
 174 #define TARGET_ASM_UNIQUE_SECTION  rs6000_xcoff_unique_section
 175 #define TARGET_STRIP_NAME_ENCODING  rs6000_xcoff_strip_name_encoding
 176 #define TARGET_SECTION_TYPE_FLAGS  rs6000_xcoff_section_type_flags
 177
 178 /* FP save and restore routines.  */
 179 #define SAVE_FP_PREFIX "._savef"
 180 #define SAVE_FP_SUFFIX ""
 181 #define RESTORE_FP_PREFIX "._restf"
 182 #define RESTORE_FP_SUFFIX ""
 183
 184 /* Function name to call to do profiling.  */
 185 #undef  RS6000_MCOUNT
 186 #define RS6000_MCOUNT ".__mcount"
 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 #undef TARGET_ASM_FILE_START
 206 #define TARGET_ASM_FILE_START rs6000_xcoff_file_start
 207 #define TARGET_ASM_FILE_END rs6000_xcoff_file_end
 208 #undef TARGET_ASM_FILE_START_FILE_DIRECTIVE
 209 #define TARGET_ASM_FILE_START_FILE_DIRECTIVE false
 210
 211 /* This macro produces the initial definition of a function name.
 212    On the RS/6000, we need to place an extra '.' in the function name and
 213    output the function descriptor.
 214
 215    The csect for the function will have already been created by the
 216    `text_section' call previously done.  We do have to go back to that
 217    csect, however.
 218
 219    The third and fourth parameters to the .function pseudo-op (16 and 044)
 220    are placeholders which no longer have any use.  */
 221
 222 #define ASM_DECLARE_FUNCTION_NAME(FILE,NAME,DECL)               \
 223 { if (TREE_PUBLIC (DECL))                                       \
 224     {                                                           \
 225       if (!RS6000_WEAK || !DECL_WEAK (decl))                    \
 226         {                                                       \
 227           fputs ("\t.globl .", FILE);                           \
 228           RS6000_OUTPUT_BASENAME (FILE, NAME);                  \
 229           putc ('\n', FILE);                                    \
 230         }                                                       \
 231     }                                                           \
 232   else                                                          \
 233     {                                                           \
 234       fputs ("\t.lglobl .", FILE);                              \
 235       RS6000_OUTPUT_BASENAME (FILE, NAME);                      \
 236       putc ('\n', FILE);                                        \
 237     }                                                           \
 238   fputs ("\t.csect ", FILE);                                    \
 239   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 240   fputs (TARGET_32BIT ? "[DS]\n" : "[DS],3\n", FILE);           \
 241   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 242   fputs (":\n", FILE);                                          \
 243   fputs (TARGET_32BIT ? "\t.long ." : "\t.llong .", FILE);      \
 244   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 245   fputs (", TOC[tc0], 0\n", FILE);                              \
 246   in_section = no_section;                                      \
 247   function_section(DECL);                                       \
 248   putc ('.', FILE);                                             \
 249   RS6000_OUTPUT_BASENAME (FILE, NAME);                          \
 250   fputs (":\n", FILE);                                          \
 251   if (write_symbols != NO_DEBUG)                                \
 252     xcoffout_declare_function (FILE, DECL, NAME);               \
 253 }
 254
 255 /* Output a reference to SYM on FILE.  */
 256
 257 #define ASM_OUTPUT_SYMBOL_REF(FILE, SYM) \
 258   rs6000_output_symbol_ref (FILE, SYM)
 259
 260 /* This says how to output an external.  */
 261
 262 #undef  ASM_OUTPUT_EXTERNAL
 263 #define ASM_OUTPUT_EXTERNAL(FILE, DECL, NAME)                           \
 264 { rtx _symref = XEXP (DECL_RTL (DECL), 0);                              \
 265   if ((TREE_CODE (DECL) == VAR_DECL                                     \
 266        || TREE_CODE (DECL) == FUNCTION_DECL)                            \
 267       && (NAME)[strlen (NAME) - 1] != ']')                              \
 268     {                                                                   \
 269       XSTR (_symref, 0) = concat (XSTR (_symref, 0),                    \
 270                                   (TREE_CODE (DECL) == FUNCTION_DECL    \
 271                                    ? "[DS]" : "[RW]"),                  \
 272                                   NULL);                                \
 273     }                                                                   \
 274 }
 275
 276 /* This is how to output an internal label prefix.  rs6000.c uses this
 277    when generating traceback tables.  */
 278
 279 #define ASM_OUTPUT_INTERNAL_LABEL_PREFIX(FILE,PREFIX)   \
 280   fprintf (FILE, "%s..", PREFIX)
 281
 282 /* This is how to output a label for a jump table.  Arguments are the same as
 283    for (*targetm.asm_out.internal_label), except the insn for the jump table is
 284    passed.  */
 285
 286 #define ASM_OUTPUT_CASE_LABEL(FILE,PREFIX,NUM,TABLEINSN)        \
 287 { ASM_OUTPUT_ALIGN (FILE, 2); (*targetm.asm_out.internal_label) (FILE, PREFIX, NUM); }
 288
 289 /* This is how to store into the string LABEL
 290    the symbol_ref name of an internal numbered label where
 291    PREFIX is the class of label and NUM is the number within the class.
 292    This is suitable for output with `assemble_name'.  */
 293
 294 #define ASM_GENERATE_INTERNAL_LABEL(LABEL,PREFIX,NUM)   \
 295   sprintf (LABEL, "*%s..%u", (PREFIX), (unsigned) (NUM))
 296
 297 /* This is how to output an assembler line to define N characters starting
 298    at P to FILE.  */
 299
 300 #define ASM_OUTPUT_ASCII(FILE, P, N)  output_ascii ((FILE), (P), (N))
 301
 302 /* This is how to advance the location counter by SIZE bytes.  */
 303
 304 #define SKIP_ASM_OP "\t.space "
 305
 306 #define ASM_OUTPUT_SKIP(FILE,SIZE)  \
 307   fprintf (FILE, "%s"HOST_WIDE_INT_PRINT_UNSIGNED"\n", SKIP_ASM_OP, (SIZE))
 308
 309 /* This says how to output an assembler line
 310    to define a global common symbol.  */
 311
 312 #define COMMON_ASM_OP "\t.comm "
 313
 314 #define ASM_OUTPUT_ALIGNED_COMMON(FILE, NAME, SIZE, ALIGN)      \
 315   do { fputs (COMMON_ASM_OP, (FILE));                   \
 316        RS6000_OUTPUT_BASENAME ((FILE), (NAME));         \
 317        if ((ALIGN) > 32)                                \
 318          fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%u\n", (SIZE), \
 319                   exact_log2 ((ALIGN) / BITS_PER_UNIT)); \
 320        else if ((SIZE) > 4)                             \
 321          fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",3\n", (SIZE)); \
 322        else                                             \
 323          fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED"\n", (SIZE)); \
 324   } while (0)
 325
 326 /* This says how to output an assembler line
 327    to define a local common symbol.
 328    Alignment cannot be specified, but we can try to maintain
 329    alignment after preceding TOC section if it was aligned
 330    for 64-bit mode.  */
 331
 332 #define LOCAL_COMMON_ASM_OP "\t.lcomm "
 333
 334 #define ASM_OUTPUT_LOCAL(FILE, NAME, SIZE, ROUNDED)     \
 335   do { fputs (LOCAL_COMMON_ASM_OP, (FILE));             \
 336        RS6000_OUTPUT_BASENAME ((FILE), (NAME));         \
 337        fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%s\n", \
 338                 (TARGET_32BIT ? (SIZE) : (ROUNDED)),    \
 339                 xcoff_bss_section_name);                \
 340      } while (0)
 341
 342 /* This is how we tell the assembler that two symbols have the same value.  */
 343 #define SET_ASM_OP "\t.set "
 344
 345 /* This is how we tell the assembler to equate two values.  */
 346 #define ASM_OUTPUT_DEF(FILE,LABEL1,LABEL2)                              \
 347  do {   fprintf ((FILE), "%s", SET_ASM_OP);                             \
 348         RS6000_OUTPUT_BASENAME (FILE, LABEL1);                          \
 349         fprintf (FILE, ",");                                            \
 350         RS6000_OUTPUT_BASENAME (FILE, LABEL2);                          \
 351         fprintf (FILE, "\n");                                           \
 352   } while (0)
 353
 354 /* Used by rs6000_assemble_integer, among others.  */
 355 #define DOUBLE_INT_ASM_OP "\t.llong\t"
 356
 357 /* Output before instructions.  */
 358 #define TEXT_SECTION_ASM_OP "\t.csect .text[PR]"
 359
 360 /* Output before writable data.
 361    Align entire section to BIGGEST_ALIGNMENT.  */
 362 #define DATA_SECTION_ASM_OP "\t.csect .data[RW],3"
 363
 364 /* Define the name of the section to use for the EH language specific
 365    data areas (.gcc_except_table on most other systems).  */
 366 #define TARGET_ASM_EXCEPTION_SECTION data_section
 367
 368 /* Define to prevent DWARF2 unwind info in the data section rather
 369    than in the .eh_frame section.  We do this because the AIX linker
 370    would otherwise garbage collect these sections.  */
 371 #define EH_FRAME_IN_DATA_SECTION 1