gcc/config/i386/sysv3.h

   1 /* Definitions for Intel 386 running system V.
   2    Copyright (C) 1988, 1996 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU CC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21
  22 #include "i386/i386.h"
  23
  24 /* Use default settings for system V.3.  */
  25
  26 #include "svr3.h"
  27
  28 /* Use the ATT assembler syntax.
  29    This overrides at least one macro (USER_LABEL_PREFIX) from svr3.h.  */
  30
  31 #include "i386/att.h"
  32
  33 /* Use crt1.o as a startup file and crtn.o as a closing file.  */
  34
  35 #define STARTFILE_SPEC  \
  36   "%{pg:gcrt1.o%s}%{!pg:%{posix:%{p:mcrtp1.o%s}%{!p:crtp1.o%s}}%{!posix:%{p:mcrt1.o%s}%{!p:crt1.o%s}}} crtbegin.o%s\
  37    %{p:-L/usr/lib/libp}%{pg:-L/usr/lib/libp}"
  38
  39 /* ??? There is a suggestion that -lg is needed here.
  40    Does anyone know whether this is right?  */
  41 #define LIB_SPEC "%{posix:-lcposix} %{shlib:-lc_s} -lc crtend.o%s crtn.o%s"
  42
  43 /* Specify predefined symbols in preprocessor.  */
  44
  45 #define CPP_PREDEFINES "-Dunix -Asystem(svr3)"
  46
  47 #define CPP_SPEC "%(cpp_cpu) %{posix:-D_POSIX_SOURCE}"
  48
  49 /* Writing `int' for a bitfield forces int alignment for the structure.  */
  50
  51 #define PCC_BITFIELD_TYPE_MATTERS 1
  52
  53 /* Don't write a `.optim' pseudo; this assembler doesn't handle them.  */
  54
  55 #undef ASM_FILE_START_1
  56 #define ASM_FILE_START_1(FILE)
  57
  58 /* We want to be able to get DBX debugging information via -gstabs.  */
  59
  60 #undef DBX_DEBUGGING_INFO
  61 #define DBX_DEBUGGING_INFO
  62
  63 #undef PREFERRED_DEBUGGING_TYPE
  64 #define PREFERRED_DEBUGGING_TYPE SDB_DEBUG
  65 \f
  66 /* longjmp may fail to restore the registers if called from the same
  67    function that called setjmp.  To compensate, the compiler avoids
  68    putting variables in registers in functions that use both setjmp
  69    and longjmp.  */
  70
  71 #define NON_SAVING_SETJMP \
  72   (current_function_calls_setjmp && current_function_calls_longjmp)
  73
  74 /* longjmp may fail to restore the stack pointer if the saved frame
  75    pointer is the same as the caller's frame pointer.  Requiring a frame
  76    pointer in any function that calls setjmp or longjmp avoids this
  77    problem, unless setjmp and longjmp are called from the same function.
  78    Since a frame pointer will be required in such a function, it is OK
  79    that the stack pointer is not restored.  */
  80
  81 #undef FRAME_POINTER_REQUIRED
  82 #define FRAME_POINTER_REQUIRED \
  83   (current_function_calls_setjmp || current_function_calls_longjmp)
  84
  85 /* Modify ASM_OUTPUT_LOCAL slightly to test -msvr3-shlib.  */
  86 #undef ASM_OUTPUT_LOCAL
  87 #define ASM_OUTPUT_LOCAL(FILE, NAME, SIZE, ROUNDED)     \
  88   do {                                                  \
  89     int align = exact_log2 (ROUNDED);                   \
  90     if (align > 2) align = 2;                           \
  91     if (TARGET_SVR3_SHLIB)                              \
  92       data_section ();                                  \
  93     else                                                \
  94       bss_section ();                                   \
  95     ASM_OUTPUT_ALIGN ((FILE), align == -1 ? 2 : align); \
  96     ASM_OUTPUT_LABEL ((FILE), (NAME));                  \
  97     fprintf ((FILE), "\t.set .,.+%u\n", (ROUNDED));     \
  98   } while (0)
  99 \f
 100 /* Define a few machine-specific details of the implementation of
 101    constructors.
 102
 103    The __CTORS_LIST__ goes in the .init section.  Define CTOR_LIST_BEGIN
 104    and CTOR_LIST_END to contribute to the .init section an instruction to
 105    push a word containing 0 (or some equivalent of that).
 106
 107    ASM_OUTPUT_CONSTRUCTOR should be defined to push the address of the
 108    constructor.  */
 109
 110 #undef INIT_SECTION_ASM_OP
 111 #define INIT_SECTION_ASM_OP     ".section .init,\"x\""
 112
 113 #define CTOR_LIST_BEGIN                         \
 114   asm (INIT_SECTION_ASM_OP);                    \
 115   asm ("pushl $0")
 116 #define CTOR_LIST_END CTOR_LIST_BEGIN
 117
 118 #define ASM_OUTPUT_CONSTRUCTOR(FILE,NAME)       \
 119   do {                                          \
 120     init_section ();                            \
 121     fprintf (FILE, "\tpushl $");                \
 122     assemble_name (FILE, NAME);                 \
 123     fprintf (FILE, "\n");                       \
 124   } while (0)