gcc/config/i386/sysv4.h

   1 /* Target definitions for GNU compiler for Intel 80386 running System V.4
   2    Copyright (C) 1991, 2001 Free Software Foundation, Inc.
   3
   4    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
  24 #undef TARGET_VERSION
  25 #define TARGET_VERSION fprintf (stderr, " (i386 System V Release 4)");
  26
  27 /* The svr4 ABI for the i386 says that records and unions are returned
  28    in memory.  */
  29
  30 #undef RETURN_IN_MEMORY
  31 #define RETURN_IN_MEMORY(TYPE) \
  32   (TYPE_MODE (TYPE) == BLKmode \
  33    || (VECTOR_MODE_P (TYPE_MODE (TYPE)) && int_size_in_bytes (TYPE) == 8))
  34
  35 /* Define which macros to predefine.  __svr4__ is our extension.  */
  36 /* This used to define X86, but james@bigtex.cactus.org says that
  37    is supposed to be defined optionally by user programs--not by default.  */
  38 #define CPP_PREDEFINES \
  39   "-Dunix -D__svr4__ -Asystem=unix -Asystem=svr4"
  40
  41 /* Output at beginning of assembler file.  */
  42 /* The .file command should always begin the output.  */
  43
  44 #undef ASM_FILE_START
  45 #define ASM_FILE_START(FILE)                                            \
  46   do {                                                                  \
  47         output_file_directive (FILE, main_input_filename);              \
  48         fprintf (FILE, "\t.version\t\"01.01\"\n");                      \
  49   } while (0)
  50
  51 #undef DBX_REGISTER_NUMBER
  52 #define DBX_REGISTER_NUMBER(n)  svr4_dbx_register_map[n]
  53
  54 /* The routine used to output sequences of byte values.  We use a special
  55    version of this for most svr4 targets because doing so makes the
  56    generated assembly code more compact (and thus faster to assemble)
  57    as well as more readable.  Note that if we find subparts of the
  58    character sequence which end with NUL (and which are shorter than
  59    STRING_LIMIT) we output those using ASM_OUTPUT_LIMITED_STRING.  */
  60
  61 #undef ASM_OUTPUT_ASCII
  62 #define ASM_OUTPUT_ASCII(FILE, STR, LENGTH)                             \
  63   do                                                                    \
  64     {                                                                   \
  65       register const unsigned char *_ascii_bytes =                      \
  66         (const unsigned char *) (STR);                                  \
  67       register const unsigned char *limit = _ascii_bytes + (LENGTH);    \
  68       register unsigned bytes_in_chunk = 0;                             \
  69       for (; _ascii_bytes < limit; _ascii_bytes++)                      \
  70         {                                                               \
  71           register const unsigned char *p;                              \
  72           if (bytes_in_chunk >= 64)                                     \
  73             {                                                           \
  74               fputc ('\n', (FILE));                                     \
  75               bytes_in_chunk = 0;                                       \
  76             }                                                           \
  77           for (p = _ascii_bytes; p < limit && *p != '\0'; p++)          \
  78             continue;                                                   \
  79           if (p < limit && (p - _ascii_bytes) <= (long) STRING_LIMIT)   \
  80             {                                                           \
  81               if (bytes_in_chunk > 0)                                   \
  82                 {                                                       \
  83                   fputc ('\n', (FILE));                                 \
  84                   bytes_in_chunk = 0;                                   \
  85                 }                                                       \
  86               ASM_OUTPUT_LIMITED_STRING ((FILE), _ascii_bytes);         \
  87               _ascii_bytes = p;                                         \
  88             }                                                           \
  89           else                                                          \
  90             {                                                           \
  91               if (bytes_in_chunk == 0)                                  \
  92                 fprintf ((FILE), "\t.byte\t");                          \
  93               else                                                      \
  94                 fputc (',', (FILE));                                    \
  95               fprintf ((FILE), "0x%02x", *_ascii_bytes);                \
  96               bytes_in_chunk += 5;                                      \
  97             }                                                           \
  98         }                                                               \
  99       if (bytes_in_chunk > 0)                                           \
 100         fprintf ((FILE), "\n");                                         \
 101     }                                                                   \
 102   while (0)
 103
 104 /* A C statement (sans semicolon) to output to the stdio stream
 105    FILE the assembler definition of uninitialized global DECL named
 106    NAME whose size is SIZE bytes and alignment is ALIGN bytes.
 107    Try to use asm_output_aligned_bss to implement this macro.  */
 108
 109 #define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \
 110   asm_output_aligned_bss (FILE, DECL, NAME, SIZE, ALIGN)
 111
 112 /* Handle special EH pointer encodings.  Absolute, pc-relative, and
 113    indirect are handled automatically.  */
 114 #define ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX(FILE, ENCODING, SIZE, ADDR, DONE) \
 115   do {                                                                  \
 116     if ((SIZE) == 4 && ((ENCODING) & 0x70) == DW_EH_PE_datarel)         \
 117       {                                                                 \
 118         fputs (ASM_LONG, FILE);                                         \
 119         assemble_name (FILE, XSTR (ADDR, 0));                           \
 120         fputs (((ENCODING) & DW_EH_PE_indirect ? "@GOT" : "@GOTOFF"), FILE); \
 121         goto DONE;                                                      \
 122       }                                                                 \
 123   } while (0)
 124
 125 /* Used by crtstuff.c to initialize the base of data-relative relocations.
 126    These are GOT relative on x86, so return the pic register.  */
 127 #ifdef __PIC__
 128 #define CRT_GET_RFIB_DATA(BASE)                 \
 129   {                                             \
 130     register void *ebx_ __asm__("ebx");         \
 131     BASE = ebx_;                                \
 132   }
 133 #else
 134 #define CRT_GET_RFIB_DATA(BASE)                                         \
 135   __asm__ ("call\t.LPR%=\n"                                             \
 136            ".LPR%=:\n\t"                                                \
 137            "popl\t%0\n\t"                                               \
 138            /* Due to a GAS bug, this cannot use EAX.  That encodes      \
 139               smaller than the traditional EBX, which results in the    \
 140               offset being off by one.  */                              \
 141            "addl\t$_GLOBAL_OFFSET_TABLE_+[.-.LPR%=],%0"                 \
 142            : "=d"(BASE))
 143 #endif