gcc/config/arm/coff.h

   1 /* Definitions of target machine for GNU compiler,
   2    for ARM with COFF obj format.
   3    Copyright (C) 1995, 1996, 1997, 1998 Free Software Foundation, Inc.
   4    Contributed by Doug Evans (dje@cygnus.com).
   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 #include "arm/semi.h"
  24 #include "arm/aout.h"
  25
  26 /* Note - it is important that this definition matches the one in tcoff.h */
  27 #undef  USER_LABEL_PREFIX
  28 #define USER_LABEL_PREFIX "_"
  29
  30 \f
  31 /* Run-time Target Specification.  */
  32 #undef  TARGET_VERSION
  33 #define TARGET_VERSION fputs (" (ARM/coff)", stderr)
  34
  35 #undef  TARGET_DEFAULT
  36 #define TARGET_DEFAULT (ARM_FLAG_SOFT_FLOAT | ARM_FLAG_APCS_32)
  37
  38 #define MULTILIB_DEFAULTS { "mlittle-endian", "msoft-float", "mapcs-32", "mno-thumb-interwork" }
  39 \f
  40 /* Setting this to 32 produces more efficient code, but the value set in previous
  41    versions of this toolchain was 8, which produces more compact structures. The
  42    command line option -mstructure_size_boundary=<n> can be used to change this
  43    value.  */
  44 #undef  STRUCTURE_SIZE_BOUNDARY
  45 #define STRUCTURE_SIZE_BOUNDARY arm_structure_size_boundary
  46
  47 extern int arm_structure_size_boundary;
  48 \f
  49 /* A C expression whose value is nonzero if IDENTIFIER with arguments ARGS
  50    is a valid machine specific attribute for DECL.
  51    The attributes in ATTRIBUTES have previously been assigned to DECL.  */
  52 #define VALID_MACHINE_DECL_ATTRIBUTE(DECL, ATTRIBUTES, IDENTIFIER, ARGS) \
  53   arm_valid_machine_decl_attribute (DECL, IDENTIFIER, ARGS)
  54 \f
  55 /* This is COFF, but prefer stabs.  */
  56 #define SDB_DEBUGGING_INFO
  57
  58 #define PREFERRED_DEBUGGING_TYPE DBX_DEBUG
  59
  60 #include "dbxcoff.h"
  61 \f
  62 /* A C statement to output assembler commands which will identify the
  63    object file as having been compiled with GNU CC (or another GNU
  64    compiler).  */
  65 /* Define this to NULL so we don't get anything.
  66    We have ASM_IDENTIFY_LANGUAGE.
  67    Also, when using stabs, gcc2_compiled must be a stabs entry, not an
  68    ordinary symbol, or gdb won't see it.  The stabs entry must be
  69    before the N_SO in order for gdb to find it.  */
  70 #define ASM_IDENTIFY_GCC(STREAM)                                \
  71   fprintf (STREAM, "%sgcc2_compiled.:\n", LOCAL_LABEL_PREFIX )
  72
  73 /* This outputs a lot of .req's to define alias for various registers.
  74    Let's try to avoid this.  */
  75 #undef ASM_FILE_START
  76 #define ASM_FILE_START(STREAM)                                  \
  77   do                                                            \
  78     {                                                           \
  79       extern char * version_string;                             \
  80       fprintf (STREAM, "%s Generated by gcc %s for ARM/coff\n", \
  81                ASM_COMMENT_START, version_string);              \
  82       fprintf (STREAM, ASM_APP_OFF);                            \
  83     }                                                           \
  84   while (0)
  85
  86 /* A C statement to output something to the assembler file to switch to section
  87    NAME for object DECL which is either a FUNCTION_DECL, a VAR_DECL or
  88    NULL_TREE.  Some target formats do not support arbitrary sections.  Do not
  89    define this macro in such cases.  */
  90 #undef  ASM_OUTPUT_SECTION_NAME
  91 #define ASM_OUTPUT_SECTION_NAME(STREAM, DECL, NAME, RELOC)      \
  92   do                                                            \
  93     {                                                           \
  94       if ((DECL) && TREE_CODE (DECL) == FUNCTION_DECL)          \
  95         fprintf (STREAM, "\t.section %s,\"x\"\n", (NAME));      \
  96       else if ((DECL) && DECL_READONLY_SECTION (DECL, RELOC))   \
  97         fprintf (STREAM, "\t.section %s,\"\"\n", (NAME));       \
  98       else                                                      \
  99         fprintf (STREAM, "\t.section %s,\"w\"\n", (NAME));      \
 100     }                                                           \
 101   while (0)
 102 \f
 103 /* Support the ctors/dtors and other sections.  */
 104
 105 #undef INIT_SECTION_ASM_OP
 106
 107 /* Define this macro if jump tables (for `tablejump' insns) should be
 108    output in the text section, along with the assembler instructions.
 109    Otherwise, the readonly data section is used.  */
 110 #define JUMP_TABLES_IN_TEXT_SECTION 1
 111
 112 #undef  READONLY_DATA_SECTION
 113 #define READONLY_DATA_SECTION   rdata_section
 114 #undef  RDATA_SECTION_ASM_OP
 115 #define RDATA_SECTION_ASM_OP    "\t.section .rdata"
 116 #undef  CTORS_SECTION_ASM_OP
 117 #define CTORS_SECTION_ASM_OP    "\t.section .ctors,\"x\""
 118 #undef  DTORS_SECTION_ASM_OP
 119 #define DTORS_SECTION_ASM_OP    "\t.section .dtors,\"x\""
 120
 121 /* A list of other sections which the compiler might be "in" at any
 122    given time.  */
 123
 124 #undef EXTRA_SECTIONS
 125 #define EXTRA_SECTIONS SUBTARGET_EXTRA_SECTIONS in_rdata, in_ctors, in_dtors
 126
 127 #define SUBTARGET_EXTRA_SECTIONS
 128
 129 /* A list of extra section function definitions.  */
 130
 131 #undef EXTRA_SECTION_FUNCTIONS
 132 #define EXTRA_SECTION_FUNCTIONS \
 133   RDATA_SECTION_FUNCTION        \
 134   CTORS_SECTION_FUNCTION        \
 135   DTORS_SECTION_FUNCTION        \
 136   SUBTARGET_EXTRA_SECTION_FUNCTIONS
 137
 138 #define SUBTARGET_EXTRA_SECTION_FUNCTIONS
 139
 140 #define RDATA_SECTION_FUNCTION \
 141 void                                                                    \
 142 rdata_section ()                                                        \
 143 {                                                                       \
 144   if (in_section != in_rdata)                                           \
 145     {                                                                   \
 146       fprintf (asm_out_file, "%s\n", RDATA_SECTION_ASM_OP);             \
 147       in_section = in_rdata;                                            \
 148     }                                                                   \
 149 }
 150
 151 #define CTORS_SECTION_FUNCTION \
 152 void                                                                    \
 153 ctors_section ()                                                        \
 154 {                                                                       \
 155   if (in_section != in_ctors)                                           \
 156     {                                                                   \
 157       fprintf (asm_out_file, "%s\n", CTORS_SECTION_ASM_OP);             \
 158       in_section = in_ctors;                                            \
 159     }                                                                   \
 160 }
 161
 162 #define DTORS_SECTION_FUNCTION \
 163 void                                                                    \
 164 dtors_section ()                                                        \
 165 {                                                                       \
 166   if (in_section != in_dtors)                                           \
 167     {                                                                   \
 168       fprintf (asm_out_file, "%s\n", DTORS_SECTION_ASM_OP);             \
 169       in_section = in_dtors;                                            \
 170     }                                                                   \
 171 }
 172 \f
 173 /* Support the ctors/dtors sections for g++.  */
 174
 175 #define INT_ASM_OP ".word"
 176
 177 /* A C statement (sans semicolon) to output an element in the table of
 178    global constructors.  */
 179 #undef ASM_OUTPUT_CONSTRUCTOR
 180 #define ASM_OUTPUT_CONSTRUCTOR(STREAM, NAME)    \
 181   do                                            \
 182     {                                           \
 183       ctors_section ();                         \
 184       fprintf (STREAM, "\t%s\t ", INT_ASM_OP);  \
 185       assemble_name (STREAM, NAME);             \
 186       fprintf (STREAM, "\n");                   \
 187     }                                           \
 188   while (0)
 189
 190 /* A C statement (sans semicolon) to output an element in the table of
 191    global destructors.  */
 192 #undef ASM_OUTPUT_DESTRUCTOR
 193 #define ASM_OUTPUT_DESTRUCTOR(STREAM, NAME)     \
 194   do                                            \
 195     {                                           \
 196       dtors_section ();                         \
 197       fprintf (STREAM, "\t%s\t ", INT_ASM_OP);  \
 198       assemble_name (STREAM, NAME);             \
 199       fprintf (STREAM, "\n");                   \
 200     }                                           \
 201   while (0)
 202
 203 /* __CTOR_LIST__ and __DTOR_LIST__ must be defined by the linker script.  */
 204 #define CTOR_LISTS_DEFINED_EXTERNALLY
 205
 206 #undef DO_GLOBAL_CTORS_BODY
 207 #undef DO_GLOBAL_DTORS_BODY
 208
 209 /* If you don't define HAVE_ATEXIT, and the object file format/OS/whatever
 210    does not support constructors/destructors, then gcc implements destructors
 211    by defining its own exit function, which calls the destructors.  This gcc
 212    exit function overrides the C library's exit function, and this can cause
 213    all kinds of havoc if the C library has a non-trivial exit function.  You
 214    really don't want to use the exit function in libgcc2.c.  */
 215 #define HAVE_ATEXIT
 216
 217 /* The ARM development system defines __main.  */
 218 #define NAME__MAIN  "__gccmain"
 219 #define SYMBOL__MAIN __gccmain