gcc/config/i386/freebsd-elf.h

   1 /* Definitions for Intel 386 running FreeBSD with ELF format
   2    Copyright (C) 1996 Free Software Foundation, Inc.
   3    Contributed by Eric Youngdale.
   4    Modified for stabs-in-ELF by H.J. Lu.
   5    Adapted from GNU/Linux version by John Polstra.
   6
   7 This file is part of GNU CC.
   8
   9 GNU CC is free software; you can redistribute it and/or modify
  10 it under the terms of the GNU General Public License as published by
  11 the Free Software Foundation; either version 2, or (at your option)
  12 any later version.
  13
  14 GNU CC is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with GNU CC; see the file COPYING.  If not, write to
  21 the Free Software Foundation, 59 Temple Place - Suite 330,
  22 Boston, MA 02111-1307, USA.  */
  23
  24 #undef TARGET_VERSION
  25 #define TARGET_VERSION fprintf (stderr, " (i386 FreeBSD/ELF)");
  26
  27 /* The svr4 ABI for the i386 says that records and unions are returned
  28    in memory.  */
  29 #undef DEFAULT_PCC_STRUCT_RETURN
  30 #define DEFAULT_PCC_STRUCT_RETURN 1
  31
  32 /* This is how to output an element of a case-vector that is relative.
  33    This is only used for PIC code.  See comments by the `casesi' insn in
  34    i386.md for an explanation of the expression this outputs. */
  35 #undef ASM_OUTPUT_ADDR_DIFF_ELT
  36 #define ASM_OUTPUT_ADDR_DIFF_ELT(FILE, VALUE, REL) \
  37   fprintf (FILE, "\t.long _GLOBAL_OFFSET_TABLE_+[.-%s%d]\n", LPREFIX, VALUE)
  38
  39 /* Indicate that jump tables go in the text section.  This is
  40    necessary when compiling PIC code.  */
  41 #define JUMP_TABLES_IN_TEXT_SECTION
  42
  43 /* Copy this from the svr4 specifications... */
  44 /* Define the register numbers to be used in Dwarf debugging information.
  45    The SVR4 reference port C compiler uses the following register numbers
  46    in its Dwarf output code:
  47         0 for %eax (gnu regno = 0)
  48         1 for %ecx (gnu regno = 2)
  49         2 for %edx (gnu regno = 1)
  50         3 for %ebx (gnu regno = 3)
  51         4 for %esp (gnu regno = 7)
  52         5 for %ebp (gnu regno = 6)
  53         6 for %esi (gnu regno = 4)
  54         7 for %edi (gnu regno = 5)
  55    The following three DWARF register numbers are never generated by
  56    the SVR4 C compiler or by the GNU compilers, but SDB on x86/svr4
  57    believes these numbers have these meanings.
  58         8  for %eip    (no gnu equivalent)
  59         9  for %eflags (no gnu equivalent)
  60         10 for %trapno (no gnu equivalent)
  61    It is not at all clear how we should number the FP stack registers
  62    for the x86 architecture.  If the version of SDB on x86/svr4 were
  63    a bit less brain dead with respect to floating-point then we would
  64    have a precedent to follow with respect to DWARF register numbers
  65    for x86 FP registers, but the SDB on x86/svr4 is so completely
  66    broken with respect to FP registers that it is hardly worth thinking
  67    of it as something to strive for compatibility with.
  68    The version of x86/svr4 SDB I have at the moment does (partially)
  69    seem to believe that DWARF register number 11 is associated with
  70    the x86 register %st(0), but that's about all.  Higher DWARF
  71    register numbers don't seem to be associated with anything in
  72    particular, and even for DWARF regno 11, SDB only seems to under-
  73    stand that it should say that a variable lives in %st(0) (when
  74    asked via an `=' command) if we said it was in DWARF regno 11,
  75    but SDB still prints garbage when asked for the value of the
  76    variable in question (via a `/' command).
  77    (Also note that the labels SDB prints for various FP stack regs
  78    when doing an `x' command are all wrong.)
  79    Note that these problems generally don't affect the native SVR4
  80    C compiler because it doesn't allow the use of -O with -g and
  81    because when it is *not* optimizing, it allocates a memory
  82    location for each floating-point variable, and the memory
  83    location is what gets described in the DWARF AT_location
  84    attribute for the variable in question.
  85    Regardless of the severe mental illness of the x86/svr4 SDB, we
  86    do something sensible here and we use the following DWARF
  87    register numbers.  Note that these are all stack-top-relative
  88    numbers.
  89         11 for %st(0) (gnu regno = 8)
  90         12 for %st(1) (gnu regno = 9)
  91         13 for %st(2) (gnu regno = 10)
  92         14 for %st(3) (gnu regno = 11)
  93         15 for %st(4) (gnu regno = 12)
  94         16 for %st(5) (gnu regno = 13)
  95         17 for %st(6) (gnu regno = 14)
  96         18 for %st(7) (gnu regno = 15)
  97 */
  98 #undef DBX_REGISTER_NUMBER
  99 #define DBX_REGISTER_NUMBER(n) \
 100 ((n) == 0 ? 0 \
 101  : (n) == 1 ? 2 \
 102  : (n) == 2 ? 1 \
 103  : (n) == 3 ? 3 \
 104  : (n) == 4 ? 6 \
 105  : (n) == 5 ? 7 \
 106  : (n) == 6 ? 5 \
 107  : (n) == 7 ? 4 \
 108  : ((n) >= FIRST_STACK_REG && (n) <= LAST_STACK_REG) ? (n)+3 \
 109  : (-1))
 110
 111 /* Output assembler code to FILE to increment profiler label # LABELNO
 112    for profiling a function entry.  */
 113
 114 #undef FUNCTION_PROFILER
 115 #define FUNCTION_PROFILER(FILE, LABELNO)  \
 116 {                                                                       \
 117   if (flag_pic)                                                         \
 118     {                                                                   \
 119       fprintf (FILE, "\tleal %sP%d@GOTOFF(%%ebx),%%edx\n",              \
 120                LPREFIX, (LABELNO));                                     \
 121       fprintf (FILE, "\tcall *mcount@GOT(%%ebx)\n");                    \
 122     }                                                                   \
 123   else                                                                  \
 124     {                                                                   \
 125       fprintf (FILE, "\tmovl $%sP%d,%%edx\n", LPREFIX, (LABELNO));      \
 126       fprintf (FILE, "\tcall mcount\n");                                \
 127     }                                                                   \
 128 }
 129
 130 #undef SIZE_TYPE
 131 #define SIZE_TYPE "unsigned int"
 132
 133 #undef PTRDIFF_TYPE
 134 #define PTRDIFF_TYPE "int"
 135
 136 #undef WCHAR_TYPE
 137 #define WCHAR_TYPE "int"
 138
 139 #undef WCHAR_TYPE_SIZE
 140 #define WCHAR_TYPE_SIZE BITS_PER_WORD
 141
 142 #undef CPP_PREDEFINES
 143 #define CPP_PREDEFINES "-Dunix -D__ELF__ -D__FreeBSD__=2 -Asystem(FreeBSD)"
 144
 145 #undef CPP_SPEC
 146 #define CPP_SPEC "%(cpp_cpu) %[cpp_cpu] %{fPIC:-D__PIC__ -D__pic__} %{fpic:-D__PIC__ -D__pic__} %{posix:-D_POSIX_SOURCE}"
 147
 148 #undef  LIB_SPEC
 149 #if 1
 150 /* We no longer link with libc_p.a or libg.a by default. If you
 151  * want to profile or debug the C library, please add
 152  * -lc_p or -ggdb to LDFLAGS at the link time, respectively.
 153  */
 154 #define LIB_SPEC \
 155   "%{!shared: %{mieee-fp:-lieee} %{p:-lgmon} %{pg:-lgmon} \
 156      %{!ggdb:-lc} %{ggdb:-lg}}"
 157 #else
 158 #define LIB_SPEC \
 159   "%{!shared: \
 160      %{mieee-fp:-lieee} %{p:-lgmon -lc_p} %{pg:-lgmon -lc_p} \
 161        %{!p:%{!pg:%{!g*:-lc} %{g*:-lg}}}}"
 162 #endif
 163
 164 /* Provide a LINK_SPEC appropriate for FreeBSD.  Here we provide support
 165    for the special GCC options -static and -shared, which allow us to
 166    link things in one of these three modes by applying the appropriate
 167    combinations of options at link-time. We like to support here for
 168    as many of the other GNU linker options as possible. But I don't
 169    have the time to search for those flags. I am sure how to add
 170    support for -soname shared_object_name. H.J.
 171
 172    I took out %{v:%{!V:-V}}. It is too much :-(. They can use
 173    -Wl,-V.
 174
 175    When the -shared link option is used a final link is not being
 176    done.  */
 177
 178 #undef  LINK_SPEC
 179 #define LINK_SPEC "-m elf_i386 %{shared:-shared} \
 180   %{!shared: \
 181     %{!ibcs: \
 182       %{!static: \
 183         %{rdynamic:-export-dynamic} \
 184         %{!dynamic-linker:-dynamic-linker /usr/libexec/ld-elf.so.1}} \
 185         %{static:-static}}}"
 186
 187 /* Get perform_* macros to build libgcc.a.  */