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 #undef  OBJECT_FORMAT_COFF
  24 #undef  EXTENDED_COFF
  25
  26 #undef  SDB_DEBUGGING_INFO
  27 #define DBX_DEBUGGING_INFO 1
  28 #define DWARF2_DEBUGGING_INFO 1
  29
  30 #undef  PREFERRED_DEBUGGING_TYPE
  31 #define PREFERRED_DEBUGGING_TYPE DWARF2_DEBUG
  32
  33 #undef  SUBTARGET_ASM_DEBUGGING_SPEC
  34 #define SUBTARGET_ASM_DEBUGGING_SPEC "-g0"
  35
  36 /* Biggest alignment supported by the object file format of this
  37    machine.  Use this macro to limit the alignment which can be
  38    specified using the `__attribute__ ((aligned (N)))' construct.  If
  39    not defined, the default value is `BIGGEST_ALIGNMENT'.  */
  40
  41 #undef MAX_OFILE_ALIGNMENT
  42 #define MAX_OFILE_ALIGNMENT (32768*8)
  43
  44 /* Switch into a generic section.  */
  45 #undef TARGET_ASM_NAMED_SECTION
  46 #define TARGET_ASM_NAMED_SECTION  default_elf_asm_named_section
  47
  48 /* Given that Irix has it's own headers, not having TARGET_GAS here
  49    seems a mistake.  If we actually need to be prepared for file
  50    switching, then we need a custom TARGET_ASM_NAMED_SECTION too.  */
  51
  52 #undef TEXT_SECTION
  53 #define TEXT_SECTION()                          \
  54 do {                                            \
  55   if (TARGET_FILE_SWITCHING)                    \
  56     abort ();                                   \
  57   fputs (TEXT_SECTION_ASM_OP, asm_out_file);    \
  58   fputc ('\n', asm_out_file);                   \
  59 } while (0)
  60
  61 /* The following macro defines the format used to output the second
  62    operand of the .type assembler directive.  Different svr4 assemblers
  63    expect various different forms for this operand.  The one given here
  64    is just a default.  You may need to override it in your machine-
  65    specific tm.h file (depending upon the particulars of your assembler).  */
  66
  67 #define TYPE_OPERAND_FMT        "@%s"
  68
  69 /* Define the strings used for the special svr4 .type and .size directives.
  70    These strings generally do not vary from one system running svr4 to
  71    another, but if a given system (e.g. m88k running svr) needs to use
  72    different pseudo-op names for these, they may be overridden in the
  73    file which includes this one.  */
  74
  75 #undef TYPE_ASM_OP
  76 #undef SIZE_ASM_OP
  77 #define TYPE_ASM_OP     "\t.type\t"
  78 #define SIZE_ASM_OP     "\t.size\t"
  79
  80 /* These macros generate the special .type and .size directives which
  81    are used to set the corresponding fields of the linker symbol table
  82    entries in an ELF object file under SVR4.  These macros also output
  83    the starting labels for the relevant functions/objects.  */
  84
  85 /* Write the extra assembler code needed to declare an object properly.  */
  86
  87 #undef ASM_DECLARE_OBJECT_NAME
  88 #define ASM_DECLARE_OBJECT_NAME(FILE, NAME, DECL)                       \
  89   do {                                                                  \
  90     HOST_WIDE_INT size;                                                 \
  91     ASM_OUTPUT_TYPE_DIRECTIVE (FILE, NAME, "object");                   \
  92     size_directive_output = 0;                                          \
  93     if (!flag_inhibit_size_directive && DECL_SIZE (DECL))               \
  94       {                                                                 \
  95         size_directive_output = 1;                                      \
  96         size = int_size_in_bytes (TREE_TYPE (DECL));                    \
  97         ASM_OUTPUT_SIZE_DIRECTIVE (FILE, NAME, size);                   \
  98       }                                                                 \
  99     mips_declare_object (FILE, NAME, "", ":\n", 0);                     \
 100   } while (0)
 101
 102 /* Output the size directive for a decl in rest_of_decl_compilation
 103    in the case where we did not do so before the initializer.
 104    Once we find the error_mark_node, we know that the value of
 105    size_directive_output was set
 106    by ASM_DECLARE_OBJECT_NAME when it was run for the same decl.  */
 107
 108 #undef ASM_FINISH_DECLARE_OBJECT
 109 #define ASM_FINISH_DECLARE_OBJECT(FILE, DECL, TOP_LEVEL, AT_END)         \
 110 do {                                                                     \
 111      const char *name = XSTR (XEXP (DECL_RTL (DECL), 0), 0);             \
 112      HOST_WIDE_INT size;                                                 \
 113      if (!flag_inhibit_size_directive && DECL_SIZE (DECL)                \
 114          && ! AT_END && TOP_LEVEL                                        \
 115          && DECL_INITIAL (DECL) == error_mark_node                       \
 116          && !size_directive_output)                                      \
 117        {                                                                 \
 118          size_directive_output = 1;                                      \
 119          size = int_size_in_bytes (TREE_TYPE (DECL));                    \
 120          ASM_OUTPUT_SIZE_DIRECTIVE (FILE, name, size);                   \
 121        }                                                                 \
 122    } while (0)
 123
 124 #define ASM_OUTPUT_DEF(FILE,LABEL1,LABEL2)                            \
 125  do { fputc ( '\t', FILE);                                            \
 126       assemble_name (FILE, LABEL1);                                   \
 127       fputs ( " = ", FILE);                                           \
 128       assemble_name (FILE, LABEL2);                                   \
 129       fputc ( '\n', FILE);                                            \
 130  } while (0)
 131
 132 /* Note about .weak vs. .weakext
 133    The mips native assemblers support .weakext, but not .weak.
 134    mips-elf gas supports .weak, but not .weakext.
 135    mips-elf gas has been changed to support both .weak and .weakext,
 136    but until that support is generally available, the 'if' below
 137    should serve.  */
 138
 139 #undef ASM_WEAKEN_LABEL
 140 #define ASM_WEAKEN_LABEL(FILE,NAME) ASM_OUTPUT_WEAK_ALIAS(FILE,NAME,0)
 141 #define ASM_OUTPUT_WEAK_ALIAS(FILE,NAME,VALUE)  \
 142  do {                                           \
 143   if (TARGET_GAS)                               \
 144       fputs ("\t.weak\t", FILE);                \
 145   else                                          \
 146       fputs ("\t.weakext\t", FILE);             \
 147   assemble_name (FILE, NAME);                   \
 148   if (VALUE)                                    \
 149     {                                           \
 150       fputc (' ', FILE);                        \
 151       assemble_name (FILE, VALUE);              \
 152     }                                           \
 153   fputc ('\n', FILE);                           \
 154  } while (0)
 155
 156 #define MAKE_DECL_ONE_ONLY(DECL) (DECL_WEAK (DECL) = 1)
 157
 158 #define TARGET_ASM_UNIQUE_SECTION mips_unique_section
 159
 160 /* A list of other sections which the compiler might be "in" at any
 161    given time.  */
 162 #undef EXTRA_SECTIONS
 163 #define EXTRA_SECTIONS in_sdata
 164
 165 #undef EXTRA_SECTION_FUNCTIONS
 166 #define EXTRA_SECTION_FUNCTIONS                                         \
 167   SECTION_FUNCTION_TEMPLATE(sdata_section, in_sdata, SDATA_SECTION_ASM_OP)
 168
 169 #define SECTION_FUNCTION_TEMPLATE(FN, ENUM, OP)                               \
 170 void FN ()                                                            \
 171 {                                                                     \
 172   if (in_section != ENUM)                                             \
 173     {                                                                 \
 174       fprintf (asm_out_file, "%s\n", OP);                             \
 175       in_section = ENUM;                                              \
 176     }                                                                 \
 177 }
 178
 179 /* On elf, we *do* have support for the .init and .fini sections, and we
 180    can put stuff in there to be executed before and after `main'.  We let
 181    crtstuff.c and other files know this by defining the following symbols.
 182    The definitions say how to change sections to the .init and .fini
 183    sections.  This is the same for all known elf assemblers.  */
 184
 185 #undef  INIT_SECTION_ASM_OP
 186 #define INIT_SECTION_ASM_OP     "\t.section\t.init"
 187 #undef  FINI_SECTION_ASM_OP
 188 #define FINI_SECTION_ASM_OP     "\t.section\t.fini"
 189
 190 /* Don't set the target flags, this is done by the linker script */
 191 #undef LIB_SPEC
 192 #define LIB_SPEC ""
 193
 194 #undef  STARTFILE_SPEC
 195 #if defined(HAVE_MIPS_LIBGLOSS_STARTUP_DIRECTIVES) \
 196     || (MIPS_ABI_DEFAULT == ABI_MEABI)
 197 #define STARTFILE_SPEC "crti%O%s crtbegin%O%s"
 198 #else
 199 #define STARTFILE_SPEC "crti%O%s crtbegin%O%s %{!mno-crt0:crt0%O%s}"
 200 #endif
 201
 202 #undef  ENDFILE_SPEC
 203 #define ENDFILE_SPEC "crtend%O%s crtn%O%s"
 204
 205 /* We support #pragma.  */
 206 #define HANDLE_SYSV_PRAGMA 1