gcc/config/i386/sysv4.h

   1 /* Target definitions for GCC for Intel 80386 running System V.4
   2    Copyright (C) 1991, 2001, 2002, 2007 Free Software Foundation, Inc.
   3
   4    Written by Ron Guilmette (rfg@netcom.com).
   5
   6 This file is part of GCC.
   7
   8 GCC 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 3, or (at your option)
  11 any later version.
  12
  13 GCC 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 GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22
  23 #define TARGET_VERSION fprintf (stderr, " (i386 System V Release 4)");
  24
  25 /* The svr4 ABI for the i386 says that records and unions are returned
  26    in memory.  */
  27
  28 #undef RETURN_IN_MEMORY
  29 #define RETURN_IN_MEMORY(TYPE) \
  30   (TYPE_MODE (TYPE) == BLKmode \
  31    || (VECTOR_MODE_P (TYPE_MODE (TYPE)) && int_size_in_bytes (TYPE) == 8))
  32
  33 /* Output at beginning of assembler file.  */
  34 /* The .file command should always begin the output.  */
  35
  36 #define TARGET_ASM_FILE_START_FILE_DIRECTIVE true
  37 #undef X86_FILE_START_VERSION_DIRECTIVE
  38 #define X86_FILE_START_VERSION_DIRECTIVE true
  39
  40 #undef DBX_REGISTER_NUMBER
  41 #define DBX_REGISTER_NUMBER(n)  svr4_dbx_register_map[n]
  42
  43 /* The routine used to output sequences of byte values.  We use a special
  44    version of this for most svr4 targets because doing so makes the
  45    generated assembly code more compact (and thus faster to assemble)
  46    as well as more readable.  Note that if we find subparts of the
  47    character sequence which end with NUL (and which are shorter than
  48    STRING_LIMIT) we output those using ASM_OUTPUT_LIMITED_STRING.  */
  49
  50 #undef ASM_OUTPUT_ASCII
  51 #define ASM_OUTPUT_ASCII(FILE, STR, LENGTH)                             \
  52   do                                                                    \
  53     {                                                                   \
  54       const unsigned char *_ascii_bytes =                               \
  55         (const unsigned char *) (STR);                                  \
  56       const unsigned char *limit = _ascii_bytes + (LENGTH);             \
  57       unsigned bytes_in_chunk = 0;                                      \
  58       for (; _ascii_bytes < limit; _ascii_bytes++)                      \
  59         {                                                               \
  60           const unsigned char *p;                                       \
  61           if (bytes_in_chunk >= 64)                                     \
  62             {                                                           \
  63               fputc ('\n', (FILE));                                     \
  64               bytes_in_chunk = 0;                                       \
  65             }                                                           \
  66           for (p = _ascii_bytes; p < limit && *p != '\0'; p++)          \
  67             continue;                                                   \
  68           if (p < limit && (p - _ascii_bytes) <= (long) STRING_LIMIT)   \
  69             {                                                           \
  70               if (bytes_in_chunk > 0)                                   \
  71                 {                                                       \
  72                   fputc ('\n', (FILE));                                 \
  73                   bytes_in_chunk = 0;                                   \
  74                 }                                                       \
  75               ASM_OUTPUT_LIMITED_STRING ((FILE), _ascii_bytes);         \
  76               _ascii_bytes = p;                                         \
  77             }                                                           \
  78           else                                                          \
  79             {                                                           \
  80               if (bytes_in_chunk == 0)                                  \
  81                 fprintf ((FILE), "\t.byte\t");                          \
  82               else                                                      \
  83                 fputc (',', (FILE));                                    \
  84               fprintf ((FILE), "0x%02x", *_ascii_bytes);                \
  85               bytes_in_chunk += 5;                                      \
  86             }                                                           \
  87         }                                                               \
  88       if (bytes_in_chunk > 0)                                           \
  89         fprintf ((FILE), "\n");                                         \
  90     }                                                                   \
  91   while (0)
  92
  93 /* A C statement (sans semicolon) to output to the stdio stream
  94    FILE the assembler definition of uninitialized global DECL named
  95    NAME whose size is SIZE bytes and alignment is ALIGN bytes.
  96    Try to use asm_output_aligned_bss to implement this macro.  */
  97
  98 #define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \
  99   asm_output_aligned_bss (FILE, DECL, NAME, SIZE, ALIGN)
 100
 101 /* Handle special EH pointer encodings.  Absolute, pc-relative, and
 102    indirect are handled automatically.  */
 103 #define ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX(FILE, ENCODING, SIZE, ADDR, DONE) \
 104   do {                                                                  \
 105     if ((SIZE) == 4 && ((ENCODING) & 0x70) == DW_EH_PE_datarel)         \
 106       {                                                                 \
 107         fputs (ASM_LONG, FILE);                                         \
 108         assemble_name (FILE, XSTR (ADDR, 0));                           \
 109         fputs (((ENCODING) & DW_EH_PE_indirect ? "@GOT" : "@GOTOFF"), FILE); \
 110         goto DONE;                                                      \
 111       }                                                                 \
 112   } while (0)
 113
 114 /* Used by crtstuff.c to initialize the base of data-relative relocations.
 115    These are GOT relative on x86, so return the pic register.  */
 116 #ifdef __PIC__
 117 #define CRT_GET_RFIB_DATA(BASE)                 \
 118   {                                             \
 119     register void *ebx_ __asm__("ebx");         \
 120     BASE = ebx_;                                \
 121   }
 122 #else
 123 #define CRT_GET_RFIB_DATA(BASE)                                         \
 124   __asm__ ("call\t.LPR%=\n"                                             \
 125            ".LPR%=:\n\t"                                                \
 126            "popl\t%0\n\t"                                               \
 127            /* Due to a GAS bug, this cannot use EAX.  That encodes      \
 128               smaller than the traditional EBX, which results in the    \
 129               offset being off by one.  */                              \
 130            "addl\t$_GLOBAL_OFFSET_TABLE_+[.-.LPR%=],%0"                 \
 131            : "=d"(BASE))
 132 #endif