| 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 I386_LINUX_SIGTRAMP |
| 102 | #define IN_SIGTRAMP(pc, name) i386_linux_in_sigtramp (pc, name) |
| 103 | extern int i386_linux_in_sigtramp (CORE_ADDR, char *); |
| 104 | |
| 105 | /* We need our own version of sigtramp_saved_pc to get the saved PC in |
| 106 | a sigtramp routine. */ |
| 107 | |
| 108 | #define sigtramp_saved_pc i386_linux_sigtramp_saved_pc |
| 109 | extern CORE_ADDR i386_linux_sigtramp_saved_pc (struct frame_info *); |
| 110 | |
| 111 | /* Signal trampolines don't have a meaningful frame. As in tm-i386.h, |
| 112 | the frame pointer value we use is actually the frame pointer of the |
| 113 | calling frame--that is, the frame which was in progress when the |
| 114 | signal trampoline was entered. gdb mostly treats this frame |
| 115 | pointer value as a magic cookie. We detect the case of a signal |
| 116 | trampoline by looking at the SIGNAL_HANDLER_CALLER field, which is |
| 117 | set based on IN_SIGTRAMP. |
| 118 | |
| 119 | When a signal trampoline is invoked from a frameless function, we |
| 120 | essentially have two frameless functions in a row. In this case, |
| 121 | we use the same magic cookie for three frames in a row. We detect |
| 122 | this case by seeing whether the next frame has |
| 123 | SIGNAL_HANDLER_CALLER set, and, if it does, checking whether the |
| 124 | current frame is actually frameless. In this case, we need to get |
| 125 | the PC by looking at the SP register value stored in the signal |
| 126 | context. |
| 127 | |
| 128 | This should work in most cases except in horrible situations where |
| 129 | a signal occurs just as we enter a function but before the frame |
| 130 | has been set up. */ |
| 131 | |
| 132 | #define FRAMELESS_SIGNAL(FRAME) \ |
| 133 | ((FRAME)->next != NULL \ |
| 134 | && (FRAME)->next->signal_handler_caller \ |
| 135 | && frameless_look_for_prologue (FRAME)) |
| 136 | |
| 137 | #undef FRAME_CHAIN |
| 138 | #define FRAME_CHAIN(FRAME) \ |
| 139 | ((FRAME)->signal_handler_caller \ |
| 140 | ? (FRAME)->frame \ |
| 141 | : (FRAMELESS_SIGNAL (FRAME) \ |
| 142 | ? (FRAME)->frame \ |
| 143 | : (!inside_entry_file ((FRAME)->pc) \ |
| 144 | ? read_memory_integer ((FRAME)->frame, 4) \ |
| 145 | : 0))) |
| 146 | |
| 147 | #undef FRAME_SAVED_PC |
| 148 | #define FRAME_SAVED_PC(FRAME) \ |
| 149 | ((FRAME)->signal_handler_caller \ |
| 150 | ? sigtramp_saved_pc (FRAME) \ |
| 151 | : (FRAMELESS_SIGNAL (FRAME) \ |
| 152 | ? read_memory_integer (i386_linux_sigtramp_saved_sp ((FRAME)->next), 4) \ |
| 153 | : read_memory_integer ((FRAME)->frame + 4, 4))) |
| 154 | |
| 155 | extern CORE_ADDR i386_linux_sigtramp_saved_sp (struct frame_info *); |
| 156 | |
| 157 | #undef SAVED_PC_AFTER_CALL |
| 158 | #define SAVED_PC_AFTER_CALL(frame) i386_linux_saved_pc_after_call (frame) |
| 159 | extern CORE_ADDR i386_linux_saved_pc_after_call (struct frame_info *); |
| 160 | |
| 161 | /* When we call a function in a shared library, and the PLT sends us |
| 162 | into the dynamic linker to find the function's real address, we |
| 163 | need to skip over the dynamic linker call. This function decides |
| 164 | when to skip, and where to skip to. See the comments for |
| 165 | SKIP_SOLIB_RESOLVER at the top of infrun.c. */ |
| 166 | #define SKIP_SOLIB_RESOLVER i386_linux_skip_solib_resolver |
| 167 | extern CORE_ADDR i386_linux_skip_solib_resolver (CORE_ADDR pc); |
| 168 | |
| 169 | /* N_FUN symbols in shared libaries have 0 for their values and need |
| 170 | to be relocated. */ |
| 171 | #define SOFUN_ADDRESS_MAYBE_MISSING |
| 172 | |
| 173 | #endif /* #ifndef TM_LINUX_H */ |