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, 2007, 2008
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GCC.
   7
   8    GCC is free software; you can redistribute it and/or modify it
   9    under the terms of the GNU General Public License as published
  10    by the Free Software Foundation; either version 3, or (at your
  11    option) any later version.
  12
  13    GCC is distributed in the hope that it will be useful, but WITHOUT
  14    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  16    License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with GCC; see the file COPYING3.  If not see
  20    <http://www.gnu.org/licenses/>.  */
  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 /* AIX .align pseudo-op accept value from 0 to 12, corresponding to
  60    log base 2 of the alignment in bytes; 12 = 4096 bytes = 32768 bits.  */
  61
  62 #define MAX_OFILE_ALIGNMENT 32768
  63
  64 /* Default alignment factor for csect directives, chosen to honor
  65    BIGGEST_ALIGNMENT.  */
  66 #define XCOFF_CSECT_DEFAULT_ALIGNMENT_STR "4"
  67
  68 /* Return nonzero if this entry is to be written into the constant
  69    pool in a special way.  We do so if this is a SYMBOL_REF, LABEL_REF
  70    or a CONST containing one of them.  If -mfp-in-toc (the default),
  71    we also do this for floating-point constants.  We actually can only
  72    do this if the FP formats of the target and host machines are the
  73    same, but we can't check that since not every file that uses
  74    GO_IF_LEGITIMATE_ADDRESS_P includes real.h.  We also do this when
  75    we can write the entry into the TOC and the entry is not larger
  76    than a TOC entry.  */
  77
  78 #define ASM_OUTPUT_SPECIAL_POOL_ENTRY_P(X, MODE)                        \
  79   (TARGET_TOC                                                           \
  80    && (GET_CODE (X) == SYMBOL_REF                                       \
  81        || (GET_CODE (X) == CONST && GET_CODE (XEXP (X, 0)) == PLUS      \
  82            && GET_CODE (XEXP (XEXP (X, 0), 0)) == SYMBOL_REF)           \
  83        || GET_CODE (X) == LABEL_REF                                     \
  84        || (GET_CODE (X) == CONST_INT                                    \
  85            && GET_MODE_BITSIZE (MODE) <= GET_MODE_BITSIZE (Pmode))      \
  86        || (GET_CODE (X) == CONST_DOUBLE                                 \
  87            && (TARGET_MINIMAL_TOC                                       \
  88                || (SCALAR_FLOAT_MODE_P (GET_MODE (X))                   \
  89                    && ! TARGET_NO_FP_IN_TOC)))))
  90
  91 #define TARGET_ASM_OUTPUT_ANCHOR  rs6000_xcoff_asm_output_anchor
  92 #define TARGET_ASM_GLOBALIZE_LABEL  rs6000_xcoff_asm_globalize_label
  93 #define TARGET_ASM_INIT_SECTIONS  rs6000_xcoff_asm_init_sections
  94 #define TARGET_ASM_RELOC_RW_MASK  rs6000_xcoff_reloc_rw_mask
  95 #define TARGET_ASM_NAMED_SECTION  rs6000_xcoff_asm_named_section
  96 #define TARGET_ASM_SELECT_SECTION  rs6000_xcoff_select_section
  97 #define TARGET_ASM_SELECT_RTX_SECTION  rs6000_xcoff_select_rtx_section
  98 #define TARGET_ASM_UNIQUE_SECTION  rs6000_xcoff_unique_section
  99 #define TARGET_ASM_FUNCTION_RODATA_SECTION default_no_function_rodata_section
 100 #define TARGET_STRIP_NAME_ENCODING  rs6000_xcoff_strip_name_encoding
 101 #define TARGET_SECTION_TYPE_FLAGS  rs6000_xcoff_section_type_flags
 102
 103 /* FP save and restore routines.  */
 104 #define SAVE_FP_PREFIX "._savef"
 105 #define SAVE_FP_SUFFIX ""
 106 #define RESTORE_FP_PREFIX "._restf"
 107 #define RESTORE_FP_SUFFIX ""
 108
 109 /* Function name to call to do profiling.  */
 110 #undef  RS6000_MCOUNT
 111 #define RS6000_MCOUNT ".__mcount"
 112
 113 /* This outputs NAME to FILE up to the first null or '['.  */
 114
 115 #define RS6000_OUTPUT_BASENAME(FILE, NAME) \
 116   assemble_name ((FILE), (*targetm.strip_name_encoding) (NAME))
 117
 118 /* This is how to output the definition of a user-level label named NAME,
 119    such as the label on a static function or variable NAME.  */
 120
 121 #define ASM_OUTPUT_LABEL(FILE,NAME)     \
 122   do { RS6000_OUTPUT_BASENAME (FILE, NAME); fputs (":\n", FILE); } while (0)
 123
 124 /* This is how to output a command to make the user-level label named NAME
 125    defined for reference from other files.  */
 126
 127 /* Globalizing directive for a label.  */
 128 #define GLOBAL_ASM_OP "\t.globl "
 129
 130 #undef TARGET_ASM_FILE_START
 131 #define TARGET_ASM_FILE_START rs6000_xcoff_file_start
 132 #define TARGET_ASM_FILE_END rs6000_xcoff_file_end
 133 #undef TARGET_ASM_FILE_START_FILE_DIRECTIVE
 134 #define TARGET_ASM_FILE_START_FILE_DIRECTIVE false
 135
 136 /* This macro produces the initial definition of a function name.
 137    On the RS/6000, we need to place an extra '.' in the function name and
 138    output the function descriptor.
 139    Dollar signs are converted to underscores.
 140
 141    The csect for the function will have already been created when
 142    text_section was selected.  We do have to go back to that csect, however.
 143
 144    The third and fourth parameters to the .function pseudo-op (16 and 044)
 145    are placeholders which no longer have any use.  */
 146
 147 #define ASM_DECLARE_FUNCTION_NAME(FILE,NAME,DECL)               \
 148 { char *buffer = (char *) alloca (strlen (NAME) + 1);           \
 149   char *p;                                                      \
 150   int dollar_inside = 0;                                        \
 151   strcpy (buffer, NAME);                                        \
 152   p = strchr (buffer, '$');                                     \
 153   while (p) {                                                   \
 154     *p = '_';                                                   \
 155     dollar_inside++;                                            \
 156     p = strchr (p + 1, '$');                                    \
 157   }                                                             \
 158   if (TREE_PUBLIC (DECL))                                       \
 159     {                                                           \
 160       if (!RS6000_WEAK || !DECL_WEAK (decl))                    \
 161         {                                                       \
 162           if (dollar_inside) {                                  \
 163               fprintf(FILE, "\t.rename .%s,\".%s\"\n", buffer, NAME);   \
 164               fprintf(FILE, "\t.rename %s,\"%s\"\n", buffer, NAME);     \
 165             }                                                   \
 166           fputs ("\t.globl .", FILE);                           \
 167           RS6000_OUTPUT_BASENAME (FILE, buffer);                \
 168           putc ('\n', FILE);                                    \
 169         }                                                       \
 170     }                                                           \
 171   else                                                          \
 172     {                                                           \
 173       if (dollar_inside) {                                      \
 174           fprintf(FILE, "\t.rename .%s,\".%s\"\n", buffer, NAME);       \
 175           fprintf(FILE, "\t.rename %s,\"%s\"\n", buffer, NAME); \
 176         }                                                       \
 177       fputs ("\t.lglobl .", FILE);                              \
 178       RS6000_OUTPUT_BASENAME (FILE, buffer);                    \
 179       putc ('\n', FILE);                                        \
 180     }                                                           \
 181   fputs ("\t.csect ", FILE);                                    \
 182   RS6000_OUTPUT_BASENAME (FILE, buffer);                        \
 183   fputs (TARGET_32BIT ? "[DS]\n" : "[DS],3\n", FILE);           \
 184   RS6000_OUTPUT_BASENAME (FILE, buffer);                        \
 185   fputs (":\n", FILE);                                          \
 186   fputs (TARGET_32BIT ? "\t.long ." : "\t.llong .", FILE);      \
 187   RS6000_OUTPUT_BASENAME (FILE, buffer);                        \
 188   fputs (", TOC[tc0], 0\n", FILE);                              \
 189   in_section = NULL;                                            \
 190   switch_to_section (function_section (DECL));                  \
 191   putc ('.', FILE);                                             \
 192   RS6000_OUTPUT_BASENAME (FILE, buffer);                        \
 193   fputs (":\n", FILE);                                          \
 194   if (write_symbols != NO_DEBUG)                                \
 195     xcoffout_declare_function (FILE, DECL, buffer);             \
 196 }
 197
 198 /* Output a reference to SYM on FILE.  */
 199
 200 #define ASM_OUTPUT_SYMBOL_REF(FILE, SYM) \
 201   rs6000_output_symbol_ref (FILE, SYM)
 202
 203 /* This says how to output an external.
 204    Dollar signs are converted to underscores.  */
 205
 206 #undef  ASM_OUTPUT_EXTERNAL
 207 #define ASM_OUTPUT_EXTERNAL(FILE, DECL, NAME)                           \
 208 { char *buffer = (char *) alloca (strlen (NAME) + 1);                   \
 209   char *p;                                                              \
 210   rtx _symref = XEXP (DECL_RTL (DECL), 0);                              \
 211   int dollar_inside = 0;                                                \
 212   strcpy (buffer, NAME);                                                \
 213   p = strchr (buffer, '$');                                             \
 214   while (p) {                                                           \
 215     *p = '_';                                                           \
 216     dollar_inside++;                                                    \
 217     p = strchr (p + 1, '$');                                            \
 218   }                                                                     \
 219   if (dollar_inside) {                                                  \
 220       fputs ("\t.extern .", FILE);                                      \
 221       RS6000_OUTPUT_BASENAME (FILE, buffer);                            \
 222       putc ('\n', FILE);                                                \
 223       fprintf(FILE, "\t.rename .%s,\".%s\"\n", buffer, NAME);           \
 224     }                                                                   \
 225   if ((TREE_CODE (DECL) == VAR_DECL                                     \
 226        || TREE_CODE (DECL) == FUNCTION_DECL)                            \
 227       && (NAME)[strlen (NAME) - 1] != ']')                              \
 228     {                                                                   \
 229       XSTR (_symref, 0) = concat (XSTR (_symref, 0),                    \
 230                                   (TREE_CODE (DECL) == FUNCTION_DECL    \
 231                                    ? "[DS]" : "[RW]"),                  \
 232                                   NULL);                                \
 233     }                                                                   \
 234 }
 235
 236 /* This is how to output a reference to a user-level label named NAME.
 237    `assemble_name' uses this.  */
 238
 239 #define ASM_OUTPUT_LABELREF(FILE,NAME)  \
 240   asm_fprintf ((FILE), "%U%s", rs6000_xcoff_strip_dollar (NAME));
 241
 242 /* This is how to output an internal label prefix.  rs6000.c uses this
 243    when generating traceback tables.  */
 244
 245 #define ASM_OUTPUT_INTERNAL_LABEL_PREFIX(FILE,PREFIX)   \
 246   fprintf (FILE, "%s..", PREFIX)
 247
 248 /* This is how to output a label for a jump table.  Arguments are the same as
 249    for (*targetm.asm_out.internal_label), except the insn for the jump table is
 250    passed.  */
 251
 252 #define ASM_OUTPUT_CASE_LABEL(FILE,PREFIX,NUM,TABLEINSN)        \
 253 { ASM_OUTPUT_ALIGN (FILE, 2); (*targetm.asm_out.internal_label) (FILE, PREFIX, NUM); }
 254
 255 /* This is how to store into the string LABEL
 256    the symbol_ref name of an internal numbered label where
 257    PREFIX is the class of label and NUM is the number within the class.
 258    This is suitable for output with `assemble_name'.  */
 259
 260 #define ASM_GENERATE_INTERNAL_LABEL(LABEL,PREFIX,NUM)   \
 261   sprintf (LABEL, "*%s..%u", rs6000_xcoff_strip_dollar (PREFIX), (unsigned) (NUM))
 262
 263 /* This is how to output an assembler line to define N characters starting
 264    at P to FILE.  */
 265
 266 #define ASM_OUTPUT_ASCII(FILE, P, N)  output_ascii ((FILE), (P), (N))
 267
 268 /* This is how to advance the location counter by SIZE bytes.  */
 269
 270 #define SKIP_ASM_OP "\t.space "
 271
 272 #define ASM_OUTPUT_SKIP(FILE,SIZE)  \
 273   fprintf (FILE, "%s"HOST_WIDE_INT_PRINT_UNSIGNED"\n", SKIP_ASM_OP, (SIZE))
 274
 275 /* This says how to output an assembler line
 276    to define a global common symbol.  */
 277
 278 #define COMMON_ASM_OP "\t.comm "
 279
 280 #define ASM_OUTPUT_ALIGNED_COMMON(FILE, NAME, SIZE, ALIGN)      \
 281   do { fputs (COMMON_ASM_OP, (FILE));                   \
 282        RS6000_OUTPUT_BASENAME ((FILE), (NAME));         \
 283        if ((ALIGN) > 32)                                \
 284          fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%u\n", (SIZE), \
 285                   exact_log2 ((ALIGN) / BITS_PER_UNIT)); \
 286        else if ((SIZE) > 4)                             \
 287          fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",3\n", (SIZE)); \
 288        else                                             \
 289          fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED"\n", (SIZE)); \
 290   } while (0)
 291
 292 /* This says how to output an assembler line
 293    to define a local common symbol.
 294    Alignment cannot be specified, but we can try to maintain
 295    alignment after preceding TOC section if it was aligned
 296    for 64-bit mode.  */
 297
 298 #define LOCAL_COMMON_ASM_OP "\t.lcomm "
 299
 300 #define ASM_OUTPUT_LOCAL(FILE, NAME, SIZE, ROUNDED)     \
 301   do { fputs (LOCAL_COMMON_ASM_OP, (FILE));             \
 302        RS6000_OUTPUT_BASENAME ((FILE), (NAME));         \
 303        fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%s\n", \
 304                 (TARGET_32BIT ? (SIZE) : (ROUNDED)),    \
 305                 xcoff_bss_section_name);                \
 306      } while (0)
 307
 308 /* This is how we tell the assembler that two symbols have the same value.  */
 309 #define SET_ASM_OP "\t.set "
 310
 311 /* This is how we tell the assembler to equate two values.  */
 312 #define ASM_OUTPUT_DEF(FILE,LABEL1,LABEL2)                              \
 313  do {   fprintf ((FILE), "%s", SET_ASM_OP);                             \
 314         RS6000_OUTPUT_BASENAME (FILE, LABEL1);                          \
 315         fprintf (FILE, ",");                                            \
 316         RS6000_OUTPUT_BASENAME (FILE, LABEL2);                          \
 317         fprintf (FILE, "\n");                                           \
 318   } while (0)
 319
 320 /* Used by rs6000_assemble_integer, among others.  */
 321 #define DOUBLE_INT_ASM_OP "\t.llong\t"
 322
 323 /* Output before instructions.  */
 324 #define TEXT_SECTION_ASM_OP "\t.csect .text[PR]"
 325
 326 /* Output before writable data.  */
 327 #define DATA_SECTION_ASM_OP \
 328   "\t.csect .data[RW]," XCOFF_CSECT_DEFAULT_ALIGNMENT_STR
 329
 330
 331 /* Define to prevent DWARF2 unwind info in the data section rather
 332    than in the .eh_frame section.  We do this because the AIX linker
 333    would otherwise garbage collect these sections.  */
 334 #define EH_FRAME_IN_DATA_SECTION 1