gcc/config/arm/linux-telf.h

   1 /* Definitions for Thumb running Linux-based GNU systems using ELF
   2    Copyright (C) 1999 Free Software Foundation, Inc.
   3    Contributed by Philip Blundell <philb@gnu.org>
   4
   5 This file is part of GNU CC.
   6
   7 GNU CC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU CC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 #define SUBTARGET_EXTRA_ASM_SPEC        \
  23         " %{fPIC:-k} %{fpic:-k}"
  24
  25 /* This was defined in linux.h.  Define it here also. */
  26 #undef  DEFAULT_VTABLE_THUNKS
  27 #define DEFAULT_VTABLE_THUNKS   1
  28
  29 /* Handle #pragma weak and #pragma pack.  */
  30 #define HANDLE_SYSV_PRAGMA
  31
  32 /* Now we define the strings used to build the spec file.  */
  33 #define LIB_SPEC \
  34   "%{shared: -lc} \
  35    %{!shared: %{pthread:-lpthread} \
  36         %{profile:-lc_p} %{!profile: -lc}}"
  37
  38 /* Provide a STARTFILE_SPEC appropriate for GNU/Linux.  Here we add
  39    the GNU/Linux magical crtbegin.o file (see crtstuff.c) which
  40    provides part of the support for getting C++ file-scope static
  41    object constructed before entering `main'. */
  42
  43 #define STARTFILE_SPEC \
  44   "%{!shared: \
  45      %{pg:gcrt1.o%s} %{!pg:%{p:gcrt1.o%s} \
  46                        %{!p:%{profile:gcrt1.o%s} \
  47                          %{!profile:crt1.o%s}}}} \
  48    crti.o%s %{!shared:crtbegin.o%s} %{shared:crtbeginS.o%s}"
  49
  50 /* Provide a ENDFILE_SPEC appropriate for GNU/Linux.  Here we tack on
  51    the GNU/Linux magical crtend.o file (see crtstuff.c) which
  52    provides part of the support for getting C++ file-scope static
  53    object constructed before entering `main', followed by a normal
  54    GNU/Linux "finalizer" file, `crtn.o'.  */
  55
  56 #define ENDFILE_SPEC \
  57   "%{!shared:crtend.o%s} %{shared:crtendS.o%s} crtn.o%s"
  58
  59 #define LINK_SPEC "%{h*} %{version:-v} \
  60    %{b} %{Wl,*:%*} \
  61    %{static:-Bstatic} \
  62    %{shared:-shared} \
  63    %{symbolic:-Bsymbolic} \
  64    %{rdynamic:-export-dynamic} \
  65    %{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.2} \
  66    -X -mno-fpu -p \
  67    %{mbig-endian:-EB} \
  68    -m armelf_linux"
  69
  70 #define CPP_PREDEFINES \
  71   "-Dunix -Dthumb -D__thumb -Dlinux \
  72 -Asystem(unix) -Asystem(posix) -Acpu(arm) \
  73 -Amachine(arm) -D__ELF__"
  74
  75 /* Allow #sccs in preprocessor.  */
  76 #define SCCS_DIRECTIVE
  77
  78 #define USER_LABEL_PREFIX       ""      /* For ELF the default is no underscores */
  79 #define LOCAL_LABEL_PREFIX      "."
  80
  81 /* Attach a special .ident directive to the end of the file to identify
  82    the version of GCC which compiled this code.  */
  83 #define IDENT_ASM_OP    ".ident"
  84
  85 /* Output #ident as a .ident.  */
  86 #define ASM_OUTPUT_IDENT(FILE, NAME) \
  87   fprintf (FILE, "\t%s\t\"%s\"\n", IDENT_ASM_OP, NAME);
  88
  89 #ifdef IDENTIFY_WITH_IDENT
  90 #define ASM_IDENTIFY_GCC(FILE) /* nothing */
  91 #define ASM_IDENTIFY_LANGUAGE(FILE)                     \
  92  fprintf (FILE, "\t%s \"GCC (%s) %s\"\n", IDENT_ASM_OP, \
  93          lang_identify (), version_string)
  94 #else
  95 #define ASM_FILE_END(FILE)                              \
  96   do                                                    \
  97     {                                                   \
  98       if (!flag_no_ident)                               \
  99         fprintf (FILE, "\t%s\t\"GCC: (GNU) %s\"\n",     \
 100                  IDENT_ASM_OP, version_string);         \
 101     }                                                   \
 102   while (0)
 103 #endif
 104
 105 /* Support const sections and the ctors and dtors sections for g++.
 106    Note that there appears to be two different ways to support const
 107    sections at the moment.  You can either #define the symbol
 108    READONLY_DATA_SECTION (giving it some code which switches to the
 109    readonly data section) or else you can #define the symbols
 110    EXTRA_SECTIONS, EXTRA_SECTION_FUNCTIONS, SELECT_SECTION, and
 111    SELECT_RTX_SECTION.  We do both here just to be on the safe side.  */
 112 #define USE_CONST_SECTION       1
 113
 114 /* Support for Constructors and Destructors.  */
 115 #define READONLY_DATA_SECTION() const_section ()
 116
 117 /* A default list of other sections which we might be "in" at any given
 118    time.  For targets that use additional sections (e.g. .tdesc) you
 119    should override this definition in the target-specific file which
 120    includes this file.  */
 121 #define SUBTARGET_EXTRA_SECTIONS in_const,
 122
 123 /* A default list of extra section function definitions.  For targets
 124    that use additional sections (e.g. .tdesc) you should override this
 125    definition in the target-specific file which includes this file.  */
 126 #define SUBTARGET_EXTRA_SECTION_FUNCTIONS       CONST_SECTION_FUNCTION
 127
 128 #define CONST_SECTION_ASM_OP    ".section\t.rodata"
 129
 130 #define CONST_SECTION_FUNCTION                                          \
 131 void                                                                    \
 132 const_section ()                                                        \
 133 {                                                                       \
 134   if (!USE_CONST_SECTION)                                               \
 135     text_section ();                                                    \
 136   else if (in_section != in_const)                                      \
 137     {                                                                   \
 138       fprintf (asm_out_file, "%s\n", CONST_SECTION_ASM_OP);             \
 139       in_section = in_const;                                            \
 140     }                                                                   \
 141 }
 142
 143 /* A C statement or statements to switch to the appropriate
 144    section for output of DECL.  DECL is either a `VAR_DECL' node
 145    or a constant of some sort.  RELOC indicates whether forming
 146    the initial value of DECL requires link-time relocations.  */
 147 #define SELECT_SECTION(DECL, RELOC)                                     \
 148 {                                                                       \
 149   if (TREE_CODE (DECL) == STRING_CST)                                   \
 150     {                                                                   \
 151       if (! flag_writable_strings)                                      \
 152         const_section ();                                               \
 153       else                                                              \
 154         data_section ();                                                \
 155     }                                                                   \
 156   else if (TREE_CODE (DECL) == VAR_DECL)                                \
 157     {                                                                   \
 158       if ((flag_pic && RELOC)                                           \
 159           || !TREE_READONLY (DECL) || TREE_SIDE_EFFECTS (DECL)          \
 160           || !DECL_INITIAL (DECL)                                       \
 161           || (DECL_INITIAL (DECL) != error_mark_node                    \
 162               && !TREE_CONSTANT (DECL_INITIAL (DECL))))                 \
 163         data_section ();                                                \
 164       else                                                              \
 165         const_section ();                                               \
 166     }                                                                   \
 167   else                                                                  \
 168     const_section ();                                                   \
 169 }
 170
 171 /* A C statement or statements to switch to the appropriate
 172    section for output of RTX in mode MODE.  RTX is some kind
 173    of constant in RTL.  The argument MODE is redundant except
 174    in the case of a `const_int' rtx.  Currently, these always
 175    go into the const section.  */
 176 #define SELECT_RTX_SECTION(MODE, RTX) const_section ()
 177
 178 /* On svr4, we *do* have support for the .init and .fini sections, and we
 179    can put stuff in there to be executed before and after `main'.  We let
 180    crtstuff.c and other files know this by defining the following symbols.
 181    The definitions say how to change sections to the .init and .fini
 182    sections.  This is the same for all known svr4 assemblers.  */
 183 #define INIT_SECTION_ASM_OP     ".section\t.init"
 184 #define FINI_SECTION_ASM_OP     ".section\t.fini"
 185
 186
 187 /* This is how we tell the assembler that a symbol is weak.  */
 188 #define ASM_WEAKEN_LABEL(FILE, NAME)            \
 189   do                                            \
 190     {                                           \
 191       fputs ("\t.weak\t", FILE);                \
 192       assemble_name (FILE, NAME);               \
 193       fputc ('\n', FILE);                       \
 194     }                                           \
 195   while (0)
 196
 197 #include "arm/telf.h"
 198 #include "arm/linux-tgas.h"
 199
 200 /* Run-time Target Specification.  */
 201 #undef TARGET_VERSION
 202 #define TARGET_VERSION  fputs (" (Thumb GNU/Linux)", stderr);