gdb/config/i386/tm-linux.h

   1 /* Definitions to target GDB to GNU/Linux on 386.
   2    Copyright 1992, 1993 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program 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 of the License, or
   9    (at your option) any later version.
  10
  11    This program 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 this program; if not, write to the Free Software
  18    Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #ifndef TM_LINUX_H
  22 #define TM_LINUX_H
  23
  24 #define I386_GNULINUX_TARGET
  25 #define HAVE_I387_REGS
  26 #ifdef HAVE_PTRACE_GETXFPREGS
  27 #define HAVE_SSE_REGS
  28 #endif
  29
  30 #include "i386/tm-i386.h"
  31 #include "tm-linux.h"
  32
  33 #define LOW_RETURN_REGNUM 0     /* holds low four bytes of result */
  34 #define HIGH_RETURN_REGNUM 2    /* holds high four bytes of result */
  35
  36 /* This should probably move to tm-i386.h.  */
  37 #define TARGET_LONG_DOUBLE_BIT 80
  38
  39 #if defined(HAVE_LONG_DOUBLE) && defined(HOST_I386)
  40 /* The host and target are i386 machines and the compiler supports
  41    long doubles. Long doubles on the host therefore have the same
  42    layout as a 387 FPU stack register. */
  43 #define LD_I387
  44
  45 extern int i387_extract_floating (PTR addr, int len, long double *dretptr);
  46 extern int i387_store_floating   (PTR addr, int len, long double val);
  47
  48 #define TARGET_EXTRACT_FLOATING i387_extract_floating
  49 #define TARGET_STORE_FLOATING   i387_store_floating
  50
  51 #define TARGET_ANALYZE_FLOATING                                 \
  52   do                                                            \
  53     {                                                           \
  54       unsigned expon;                                           \
  55                                                                 \
  56       low = extract_unsigned_integer (valaddr, 4);              \
  57       high = extract_unsigned_integer (valaddr + 4, 4);         \
  58       expon = extract_unsigned_integer (valaddr + 8, 2);        \
  59                                                                 \
  60       nonnegative = ((expon & 0x8000) == 0);                    \
  61       is_nan = ((expon & 0x7fff) == 0x7fff)                     \
  62         && ((high & 0x80000000) == 0x80000000)                  \
  63         && (((high & 0x7fffffff) | low) != 0);                  \
  64     }                                                           \
  65   while (0)
  66
  67 #undef REGISTER_CONVERT_TO_VIRTUAL
  68 #define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,TYPE,FROM,TO)        \
  69 {                                                               \
  70   long double val = *((long double *)FROM);                     \
  71   store_floating ((TO), TYPE_LENGTH (TYPE), val);               \
  72 }
  73
  74 #undef REGISTER_CONVERT_TO_RAW
  75 #define REGISTER_CONVERT_TO_RAW(TYPE,REGNUM,FROM,TO)                    \
  76 {                                                                       \
  77   long double val = extract_floating ((FROM), TYPE_LENGTH (TYPE));      \
  78   *((long double *)TO) = val;                                           \
  79 }
  80
  81 /* Return the GDB type object for the "standard" data type
  82    of data in register N.  */
  83 #undef REGISTER_VIRTUAL_TYPE
  84 #define REGISTER_VIRTUAL_TYPE(N)                                \
  85   (((N) == PC_REGNUM || (N) == FP_REGNUM || (N) == SP_REGNUM)   \
  86    ? lookup_pointer_type (builtin_type_void)                    \
  87    : IS_FP_REGNUM(N) ? builtin_type_long_double                 \
  88    : IS_SSE_REGNUM(N) ? builtin_type_v4sf                       \
  89    : builtin_type_int)
  90
  91 #endif
  92
  93 /* The following works around a problem with /usr/include/sys/procfs.h  */
  94 #define sys_quotactl 1
  95
  96 /* When the i386 Linux kernel calls a signal handler, the return
  97    address points to a bit of code on the stack.  These definitions
  98    are used to identify this bit of code as a signal trampoline in
  99    order to support backtracing through calls to signal handlers.  */
 100
 101 #define IN_SIGTRAMP(pc, name) i386_linux_in_sigtramp (pc, name)
 102 extern int i386_linux_in_sigtramp (CORE_ADDR, char *);
 103
 104 /* We need our own version of sigtramp_saved_pc to get the saved PC in
 105    a sigtramp routine.  */
 106
 107 #define sigtramp_saved_pc i386_linux_sigtramp_saved_pc
 108 extern CORE_ADDR i386_linux_sigtramp_saved_pc (struct frame_info *);
 109
 110 /* Signal trampolines don't have a meaningful frame.  As in tm-i386.h,
 111    the frame pointer value we use is actually the frame pointer of the
 112    calling frame--that is, the frame which was in progress when the
 113    signal trampoline was entered.  gdb mostly treats this frame
 114    pointer value as a magic cookie.  We detect the case of a signal
 115    trampoline by looking at the SIGNAL_HANDLER_CALLER field, which is
 116    set based on IN_SIGTRAMP.
 117
 118    When a signal trampoline is invoked from a frameless function, we
 119    essentially have two frameless functions in a row.  In this case,
 120    we use the same magic cookie for three frames in a row.  We detect
 121    this case by seeing whether the next frame has
 122    SIGNAL_HANDLER_CALLER set, and, if it does, checking whether the
 123    current frame is actually frameless.  In this case, we need to get
 124    the PC by looking at the SP register value stored in the signal
 125    context.
 126
 127    This should work in most cases except in horrible situations where
 128    a signal occurs just as we enter a function but before the frame
 129    has been set up.  */
 130
 131 #define FRAMELESS_SIGNAL(FRAME)                                 \
 132   ((FRAME)->next != NULL                                        \
 133    && (FRAME)->next->signal_handler_caller                      \
 134    && frameless_look_for_prologue (FRAME))
 135
 136 #undef FRAME_CHAIN
 137 #define FRAME_CHAIN(FRAME)                                      \
 138   ((FRAME)->signal_handler_caller                               \
 139    ? (FRAME)->frame                                             \
 140     : (FRAMELESS_SIGNAL (FRAME)                                 \
 141        ? (FRAME)->frame                                         \
 142        : (!inside_entry_file ((FRAME)->pc)                      \
 143           ? read_memory_integer ((FRAME)->frame, 4)             \
 144           : 0)))
 145
 146 #undef FRAME_SAVED_PC
 147 #define FRAME_SAVED_PC(FRAME)                                   \
 148   ((FRAME)->signal_handler_caller                               \
 149    ? sigtramp_saved_pc (FRAME)                                  \
 150    : (FRAMELESS_SIGNAL (FRAME)                                  \
 151       ? read_memory_integer (i386_linux_sigtramp_saved_sp ((FRAME)->next), 4) \
 152       : read_memory_integer ((FRAME)->frame + 4, 4)))
 153
 154 extern CORE_ADDR i386_linux_sigtramp_saved_sp (struct frame_info *);
 155
 156 #undef SAVED_PC_AFTER_CALL
 157 #define SAVED_PC_AFTER_CALL(frame) i386_linux_saved_pc_after_call (frame)
 158 extern CORE_ADDR i386_linux_saved_pc_after_call (struct frame_info *);
 159
 160 /* When we call a function in a shared library, and the PLT sends us
 161    into the dynamic linker to find the function's real address, we
 162    need to skip over the dynamic linker call.  This function decides
 163    when to skip, and where to skip to.  See the comments for
 164    SKIP_SOLIB_RESOLVER at the top of infrun.c.  */
 165 #define SKIP_SOLIB_RESOLVER i386_linux_skip_solib_resolver
 166 extern CORE_ADDR i386_linux_skip_solib_resolver (CORE_ADDR pc);
 167
 168 /* N_FUN symbols in shared libaries have 0 for their values and need
 169    to be relocated. */
 170 #define SOFUN_ADDRESS_MAYBE_MISSING
 171
 172 #endif /* #ifndef TM_LINUX_H */