gcc/config/mips/elf64.h

   1 /* Definitions of target machine for GNU compiler.  MIPS R4000 version with
   2    GOFAST floating point library.
   3    Copyright (C) 1994, 1995, 1996, 1997, 1999, 2000, 2002
   4    Free Software Foundation, Inc.
   5
   6 This file is part of GNU CC.
   7
   8 GNU CC is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 2, or (at your option)
  11 any later version.
  12
  13 GNU CC is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GNU CC; see the file COPYING.  If not, write to
  20 the Free Software Foundation, 59 Temple Place - Suite 330,
  21 Boston, MA 02111-1307, USA.  */
  22
  23 #define OBJECT_FORMAT_ELF
  24
  25 /* Default to -mips3.  */
  26 #ifndef TARGET_DEFAULT
  27 #define TARGET_DEFAULT MASK_FLOAT64|MASK_64BIT
  28 #endif
  29
  30 #ifndef MIPS_ISA_DEFAULT
  31 #define MIPS_ISA_DEFAULT 3
  32 #endif
  33
  34 /* This should change to n32 when it is supported in gas.  */
  35 #ifndef MIPS_ABI_DEFAULT
  36 #define MIPS_ABI_DEFAULT ABI_O64
  37 #endif
  38
  39 /* Until we figure out what MIPS ELF targets normally use, just do
  40    stabs in ELF.  */
  41 #ifndef PREFERRED_DEBUGGING_TYPE
  42 #define PREFERRED_DEBUGGING_TYPE DBX_DEBUG
  43 #endif
  44
  45 /* US Software GOFAST library support.  */
  46 #include "gofast.h"
  47 #define INIT_SUBTARGET_OPTABS INIT_GOFAST_OPTABS
  48
  49 #include "mips/mips.h"
  50
  51 /* Use memcpy, et. al., rather than bcopy.  */
  52 #define TARGET_MEM_FUNCTIONS
  53
  54 /* Biggest alignment supported by the object file format of this
  55    machine.  Use this macro to limit the alignment which can be
  56    specified using the `__attribute__ ((aligned (N)))' construct.  If
  57    not defined, the default value is `BIGGEST_ALIGNMENT'.  */
  58
  59 #undef MAX_OFILE_ALIGNMENT
  60 #define MAX_OFILE_ALIGNMENT (32768*8)
  61
  62 /* We need to use .esize and .etype instead of .size and .type to
  63    avoid conflicting with ELF directives.  */
  64 #undef PUT_SDB_SIZE
  65 #define PUT_SDB_SIZE(a)                                 \
  66 do {                                                    \
  67   extern FILE *asm_out_text_file;                       \
  68   fprintf (asm_out_text_file, "\t.esize\t");            \
  69   fprintf (asm_out_text_file, HOST_WIDE_INT_PRINT_DEC, (HOST_WIDE_INT) (a)); \
  70   fprintf (asm_out_text_file, ";");                     \
  71 } while (0)
  72
  73 #undef PUT_SDB_TYPE
  74 #define PUT_SDB_TYPE(a)                                 \
  75 do {                                                    \
  76   extern FILE *asm_out_text_file;                       \
  77   fprintf (asm_out_text_file, "\t.etype\t0x%x;", (a));  \
  78 } while (0)
  79
  80 /* Switch into a generic section.  */
  81 #undef TARGET_ASM_NAMED_SECTION
  82 #define TARGET_ASM_NAMED_SECTION  default_elf_asm_named_section
  83
  84 /* Given that Irix has it's own headers, not having TARGET_GAS here
  85    seems a mistake.  If we actually need to be prepared for file
  86    switching, then we need a custom TARGET_ASM_NAMED_SECTION too.  */
  87
  88 #undef TEXT_SECTION
  89 #define TEXT_SECTION()                          \
  90 do {                                            \
  91   if (TARGET_FILE_SWITCHING)                    \
  92     abort ();                                   \
  93   fputs (TEXT_SECTION_ASM_OP, asm_out_file);    \
  94   fputc ('\n', asm_out_file);                   \
  95 } while (0)
  96
  97 /* The following macro defines the format used to output the second
  98    operand of the .type assembler directive.  Different svr4 assemblers
  99    expect various different forms for this operand.  The one given here
 100    is just a default.  You may need to override it in your machine-
 101    specific tm.h file (depending upon the particulars of your assembler).  */
 102
 103 #define TYPE_OPERAND_FMT        "@%s"
 104
 105 /* Define the strings used for the special svr4 .type and .size directives.
 106    These strings generally do not vary from one system running svr4 to
 107    another, but if a given system (e.g. m88k running svr) needs to use
 108    different pseudo-op names for these, they may be overridden in the
 109    file which includes this one.  */
 110
 111 #undef TYPE_ASM_OP
 112 #undef SIZE_ASM_OP
 113 #define TYPE_ASM_OP     "\t.type\t"
 114 #define SIZE_ASM_OP     "\t.size\t"
 115
 116 /* These macros generate the special .type and .size directives which
 117    are used to set the corresponding fields of the linker symbol table
 118    entries in an ELF object file under SVR4.  These macros also output
 119    the starting labels for the relevant functions/objects.  */
 120
 121 /* Write the extra assembler code needed to declare an object properly.  */
 122
 123 #undef ASM_DECLARE_OBJECT_NAME
 124 #define ASM_DECLARE_OBJECT_NAME(FILE, NAME, DECL)                       \
 125   do {                                                                  \
 126     fprintf (FILE, "%s", TYPE_ASM_OP);                                  \
 127     assemble_name (FILE, NAME);                                         \
 128     putc (',', FILE);                                                   \
 129     fprintf (FILE, TYPE_OPERAND_FMT, "object");                         \
 130     putc ('\n', FILE);                                                  \
 131     size_directive_output = 0;                                          \
 132     if (!flag_inhibit_size_directive && DECL_SIZE (DECL))               \
 133       {                                                                 \
 134         size_directive_output = 1;                                      \
 135         fprintf (FILE, "%s", SIZE_ASM_OP);                              \
 136         assemble_name (FILE, NAME);                                     \
 137         fprintf (FILE, ",");                                            \
 138         fprintf (FILE, HOST_WIDE_INT_PRINT_DEC,                         \
 139           int_size_in_bytes (TREE_TYPE (DECL)));                        \
 140         fprintf (FILE, "\n");                                           \
 141       }                                                                 \
 142     mips_declare_object (FILE, NAME, "", ":\n", 0);                     \
 143   } while (0)
 144
 145 /* Output the size directive for a decl in rest_of_decl_compilation
 146    in the case where we did not do so before the initializer.
 147    Once we find the error_mark_node, we know that the value of
 148    size_directive_output was set
 149    by ASM_DECLARE_OBJECT_NAME when it was run for the same decl.  */
 150
 151 #undef ASM_FINISH_DECLARE_OBJECT
 152 #define ASM_FINISH_DECLARE_OBJECT(FILE, DECL, TOP_LEVEL, AT_END)         \
 153 do {                                                                     \
 154      const char *name = XSTR (XEXP (DECL_RTL (DECL), 0), 0);             \
 155      if (!flag_inhibit_size_directive && DECL_SIZE (DECL)                \
 156          && ! AT_END && TOP_LEVEL                                        \
 157          && DECL_INITIAL (DECL) == error_mark_node                       \
 158          && !size_directive_output)                                      \
 159        {                                                                 \
 160          size_directive_output = 1;                                      \
 161          fprintf (FILE, "%s", SIZE_ASM_OP);                              \
 162          assemble_name (FILE, name);                                     \
 163          fprintf (FILE, ",");                                            \
 164          fprintf (FILE, HOST_WIDE_INT_PRINT_DEC,                         \
 165                   int_size_in_bytes (TREE_TYPE (DECL)));                 \
 166          fprintf (FILE, "\n");                                           \
 167        }                                                                 \
 168    } while (0)
 169
 170 #define ASM_OUTPUT_DEF(FILE,LABEL1,LABEL2)                            \
 171  do { fputc ( '\t', FILE);                                            \
 172       assemble_name (FILE, LABEL1);                                   \
 173       fputs ( " = ", FILE);                                           \
 174       assemble_name (FILE, LABEL2);                                   \
 175       fputc ( '\n', FILE);                                            \
 176  } while (0)
 177
 178 /* Note about .weak vs. .weakext
 179    The mips native assemblers support .weakext, but not .weak.
 180    mips-elf gas supports .weak, but not .weakext.
 181    mips-elf gas has been changed to support both .weak and .weakext,
 182    but until that support is generally available, the 'if' below
 183    should serve.  */
 184
 185 #undef ASM_WEAKEN_LABEL
 186 #define ASM_WEAKEN_LABEL(FILE,NAME) ASM_OUTPUT_WEAK_ALIAS(FILE,NAME,0)
 187 #define ASM_OUTPUT_WEAK_ALIAS(FILE,NAME,VALUE)  \
 188  do {                                           \
 189   if (TARGET_GAS)                               \
 190       fputs ("\t.weak\t", FILE);                \
 191   else                                          \
 192       fputs ("\t.weakext\t", FILE);             \
 193   assemble_name (FILE, NAME);                   \
 194   if (VALUE)                                    \
 195     {                                           \
 196       fputc (' ', FILE);                        \
 197       assemble_name (FILE, VALUE);              \
 198     }                                           \
 199   fputc ('\n', FILE);                           \
 200  } while (0)
 201
 202 #define MAKE_DECL_ONE_ONLY(DECL) (DECL_WEAK (DECL) = 1)
 203
 204 #define TARGET_ASM_UNIQUE_SECTION mips_unique_section
 205
 206 /* A list of other sections which the compiler might be "in" at any
 207    given time.  */
 208 #undef EXTRA_SECTIONS
 209 #define EXTRA_SECTIONS in_sdata
 210
 211 #undef EXTRA_SECTION_FUNCTIONS
 212 #define EXTRA_SECTION_FUNCTIONS                                         \
 213   SECTION_FUNCTION_TEMPLATE(sdata_section, in_sdata, SDATA_SECTION_ASM_OP)
 214
 215 #define SECTION_FUNCTION_TEMPLATE(FN, ENUM, OP)                               \
 216 void FN ()                                                            \
 217 {                                                                     \
 218   if (in_section != ENUM)                                             \
 219     {                                                                 \
 220       fprintf (asm_out_file, "%s\n", OP);                             \
 221       in_section = ENUM;                                              \
 222     }                                                                 \
 223 }
 224
 225 /* On elf, we *do* have support for the .init and .fini sections, and we
 226    can put stuff in there to be executed before and after `main'.  We let
 227    crtstuff.c and other files know this by defining the following symbols.
 228    The definitions say how to change sections to the .init and .fini
 229    sections.  This is the same for all known elf assemblers.  */
 230
 231 #undef  INIT_SECTION_ASM_OP
 232 #define INIT_SECTION_ASM_OP     "\t.section\t.init"
 233 #undef  FINI_SECTION_ASM_OP
 234 #define FINI_SECTION_ASM_OP     "\t.section\t.fini"
 235
 236 /* Don't set the target flags, this is done by the linker script */
 237 #undef LIB_SPEC
 238 #define LIB_SPEC ""
 239
 240 #undef  STARTFILE_SPEC
 241 #define STARTFILE_SPEC "crti%O%s crtbegin%O%s %{!mno-crt0:crt0%O%s}"
 242
 243 #undef  ENDFILE_SPEC
 244 #define ENDFILE_SPEC "crtend%O%s crtn%O%s"