gcc/config/i386/i386elf.h

   1 /* Target definitions for GNU compiler for Intel 80386 using ELF
   2    Copyright (C) 1988, 1991, 1995, 2000, 2001 Free Software Foundation, Inc.
   3
   4    Derived from sysv4.h written by Ron Guilmette (rfg@netcom.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 /* Use stabs instead of DWARF debug format.  */
  24 #undef  PREFERRED_DEBUGGING_TYPE
  25 #define PREFERRED_DEBUGGING_TYPE DBX_DEBUG
  26
  27 #undef TARGET_VERSION
  28 #define TARGET_VERSION fprintf (stderr, " (i386 bare ELF target)");
  29
  30 /* By default, target has a 80387, uses IEEE compatible arithmetic,
  31    and returns float values in the 387.  */
  32
  33 #define TARGET_SUBTARGET_DEFAULT (MASK_80387 | MASK_IEEE_FP | MASK_FLOAT_RETURNS)
  34
  35 /* The ELF ABI for the i386 says that records and unions are returned
  36    in memory.  */
  37
  38 #undef RETURN_IN_MEMORY
  39 #define RETURN_IN_MEMORY(TYPE) \
  40   (TYPE_MODE (TYPE) == BLKmode \
  41    || (VECTOR_MODE_P (TYPE_MODE (TYPE)) && int_size_in_bytes (TYPE) == 8))
  42
  43 /* This used to define X86, but james@bigtex.cactus.org says that
  44    is supposed to be defined optionally by user programs--not by default.  */
  45 #define CPP_PREDEFINES ""
  46
  47 #undef CPP_SPEC
  48 #define CPP_SPEC "%(cpp_cpu)"
  49
  50 #define ENDFILE_SPEC "crtend.o%s"
  51
  52 #define STARTFILE_SPEC "%{!shared: \
  53                          %{!symbolic: \
  54                           %{pg:gcrt0.o%s}%{!pg:%{p:mcrt0.o%s}%{!p:crt0.o%s}}}}\
  55                         crtbegin.o%s"
  56
  57 /* This is how to output assembly code to define a `float' constant.
  58    We always have to use a .long pseudo-op to do this because the native
  59    SVR4 ELF assembler is buggy and it generates incorrect values when we
  60    try to use the .float pseudo-op instead.  */
  61
  62 #undef ASM_OUTPUT_FLOAT
  63 #define ASM_OUTPUT_FLOAT(FILE,VALUE)                                    \
  64 do { long value;                                                        \
  65      REAL_VALUE_TO_TARGET_SINGLE ((VALUE), value);                      \
  66      if (sizeof (int) == sizeof (long))                                 \
  67          fprintf((FILE), "%s0x%x\n", ASM_LONG, (int) value);            \
  68      else                                                               \
  69          fprintf((FILE), "%s0x%lx\n", ASM_LONG, value);                 \
  70    } while (0)
  71
  72 /* This is how to output assembly code to define a `double' constant.
  73    We always have to use a pair of .long pseudo-ops to do this because
  74    the native SVR4 ELF assembler is buggy and it generates incorrect
  75    values when we try to use the the .double pseudo-op instead.  */
  76
  77 #undef ASM_OUTPUT_DOUBLE
  78 #define ASM_OUTPUT_DOUBLE(FILE,VALUE)                                   \
  79 do { long value[2];                                                     \
  80      REAL_VALUE_TO_TARGET_DOUBLE ((VALUE), value);                      \
  81      if (sizeof (int) == sizeof (long))                                 \
  82        {                                                                \
  83          fprintf((FILE), "%s0x%x\n", ASM_LONG, (int) value[0]);         \
  84          fprintf((FILE), "%s0x%x\n", ASM_LONG, (int) value[1]);         \
  85        }                                                                \
  86      else                                                               \
  87        {                                                                \
  88          fprintf((FILE), "%s0x%lx\n", ASM_LONG, value[0]);              \
  89          fprintf((FILE), "%s0x%lx\n", ASM_LONG, value[1]);              \
  90        }                                                                \
  91    } while (0)
  92
  93
  94 #undef ASM_OUTPUT_LONG_DOUBLE
  95 #define ASM_OUTPUT_LONG_DOUBLE(FILE,VALUE)                              \
  96 do { long value[3];                                                     \
  97      REAL_VALUE_TO_TARGET_LONG_DOUBLE ((VALUE), value);                 \
  98      if (sizeof (int) == sizeof (long))                                 \
  99        {                                                                \
 100          fprintf((FILE), "%s0x%x\n", ASM_LONG, (int) value[0]);         \
 101          fprintf((FILE), "%s0x%x\n", ASM_LONG, (int) value[1]);         \
 102          fprintf((FILE), "%s0x%x\n", ASM_LONG, (int) value[2]);         \
 103        }                                                                \
 104      else                                                               \
 105        {                                                                \
 106          fprintf((FILE), "%s0x%lx\n", ASM_LONG, value[0]);              \
 107          fprintf((FILE), "%s0x%lx\n", ASM_LONG, value[1]);              \
 108          fprintf((FILE), "%s0x%lx\n", ASM_LONG, value[2]);              \
 109        }                                                                \
 110    } while (0)
 111
 112 #undef DBX_REGISTER_NUMBER
 113 #define DBX_REGISTER_NUMBER(n) \
 114   (TARGET_64BIT ? dbx64_register_map[n] : svr4_dbx_register_map[n])
 115
 116 /* The routine used to output sequences of byte values.  We use a special
 117    version of this for most svr4 targets because doing so makes the
 118    generated assembly code more compact (and thus faster to assemble)
 119    as well as more readable.  Note that if we find subparts of the
 120    character sequence which end with NUL (and which are shorter than
 121    STRING_LIMIT) we output those using ASM_OUTPUT_LIMITED_STRING.  */
 122
 123 #undef ASM_OUTPUT_ASCII
 124 #define ASM_OUTPUT_ASCII(FILE, STR, LENGTH)                             \
 125   do                                                                    \
 126     {                                                                   \
 127       register const unsigned char *_ascii_bytes =                      \
 128         (const unsigned char *) (STR);                                  \
 129       register const unsigned char *limit = _ascii_bytes + (LENGTH);    \
 130       register unsigned bytes_in_chunk = 0;                             \
 131       for (; _ascii_bytes < limit; _ascii_bytes++)                      \
 132         {                                                               \
 133           register const unsigned char *p;                              \
 134           if (bytes_in_chunk >= 64)                                     \
 135             {                                                           \
 136               fputc ('\n', (FILE));                                     \
 137               bytes_in_chunk = 0;                                       \
 138             }                                                           \
 139           for (p = _ascii_bytes; p < limit && *p != '\0'; p++)          \
 140             continue;                                                   \
 141           if (p < limit && (p - _ascii_bytes) <= (long) STRING_LIMIT)   \
 142             {                                                           \
 143               if (bytes_in_chunk > 0)                                   \
 144                 {                                                       \
 145                   fputc ('\n', (FILE));                                 \
 146                   bytes_in_chunk = 0;                                   \
 147                 }                                                       \
 148               ASM_OUTPUT_LIMITED_STRING ((FILE), _ascii_bytes);         \
 149               _ascii_bytes = p;                                         \
 150             }                                                           \
 151           else                                                          \
 152             {                                                           \
 153               if (bytes_in_chunk == 0)                                  \
 154                 fprintf ((FILE), "\t.byte\t");                          \
 155               else                                                      \
 156                 fputc (',', (FILE));                                    \
 157               fprintf ((FILE), "0x%02x", *_ascii_bytes);                \
 158               bytes_in_chunk += 5;                                      \
 159             }                                                           \
 160         }                                                               \
 161       if (bytes_in_chunk > 0)                                           \
 162         fprintf ((FILE), "\n");                                         \
 163     }                                                                   \
 164   while (0)
 165
 166 #define LOCAL_LABEL_PREFIX      "."
 167
 168 /* Switch into a generic section.  */
 169 #define TARGET_ASM_NAMED_SECTION  default_elf_asm_named_section
 170
 171 /* If defined, a C expression whose value is a string containing the
 172    assembler operation to identify the following data as
 173    uninitialized global data.  If not defined, and neither
 174    `ASM_OUTPUT_BSS' nor `ASM_OUTPUT_ALIGNED_BSS' are defined,
 175    uninitialized global data will be output in the data section if
 176    `-fno-common' is passed, otherwise `ASM_OUTPUT_COMMON' will be
 177    used.  */
 178 #undef BSS_SECTION_ASM_OP
 179 #define BSS_SECTION_ASM_OP "\t.section\t.bss"
 180
 181 /* Like `ASM_OUTPUT_BSS' except takes the required alignment as a
 182    separate, explicit argument.  If you define this macro, it is used
 183    in place of `ASM_OUTPUT_BSS', and gives you more flexibility in
 184    handling the required alignment of the variable.  The alignment is
 185    specified as the number of bits.
 186
 187    Try to use function `asm_output_aligned_bss' defined in file
 188    `varasm.c' when defining this macro.  */
 189 #undef ASM_OUTPUT_ALIGNED_BSS
 190 #define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \
 191   asm_output_aligned_bss (FILE, DECL, NAME, SIZE, ALIGN)