gdb/amd64-nbsd-tdep.c

   1 /* Target-dependent code for NetBSD/amd64.
   2
   3    Copyright (C) 2003-2020 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "arch-utils.h"
  22 #include "frame.h"
  23 #include "gdbcore.h"
  24 #include "osabi.h"
  25 #include "symtab.h"
  26
  27 #include "amd64-tdep.h"
  28 #include "gdbsupport/x86-xstate.h"
  29 #include "nbsd-tdep.h"
  30 #include "solib-svr4.h"
  31
  32 /* Support for signal handlers.  */
  33
  34 /* Return whether THIS_FRAME corresponds to a NetBSD sigtramp
  35    routine.  */
  36
  37 static int
  38 amd64nbsd_sigtramp_p (struct frame_info *this_frame)
  39 {
  40   CORE_ADDR pc = get_frame_pc (this_frame);
  41   const char *name;
  42
  43   find_pc_partial_function (pc, &name, NULL, NULL);
  44   return nbsd_pc_in_sigtramp (pc, name);
  45 }
  46
  47 /* Assuming THIS_FRAME corresponds to a NetBSD sigtramp routine,
  48    return the address of the associated mcontext structure.  */
  49
  50 static CORE_ADDR
  51 amd64nbsd_mcontext_addr (struct frame_info *this_frame)
  52 {
  53   CORE_ADDR addr;
  54
  55   /* The register %r15 points at `struct ucontext' upon entry of a
  56      signal trampoline.  */
  57   addr = get_frame_register_unsigned (this_frame, AMD64_R15_REGNUM);
  58
  59   /* The mcontext structure lives as offset 56 in `struct ucontext'.  */
  60   return addr + 56;
  61 }
  62 \f
  63 /* NetBSD 2.0 or later.  */
  64
  65 /* Mapping between the general-purpose registers in `struct reg'
  66    format and GDB's register cache layout.  */
  67
  68 /* From <machine/reg.h>.  */
  69 int amd64nbsd_r_reg_offset[] =
  70 {
  71   14 * 8,                       /* %rax */
  72   13 * 8,                       /* %rbx */
  73   3 * 8,                        /* %rcx */
  74   2 * 8,                        /* %rdx */
  75   1 * 8,                        /* %rsi */
  76   0 * 8,                        /* %rdi */
  77   12 * 8,                       /* %rbp */
  78   24 * 8,                       /* %rsp */
  79   4 * 8,                        /* %r8 ..  */
  80   5 * 8,
  81   6 * 8,
  82   7 * 8,
  83   8 * 8,
  84   9 * 8,
  85   10 * 8,
  86   11 * 8,                       /* ... %r15 */
  87   21 * 8,                       /* %rip */
  88   23 * 8,                       /* %eflags */
  89   22 * 8,                       /* %cs */
  90   25 * 8,                       /* %ss */
  91   18 * 8,                       /* %ds */
  92   17 * 8,                       /* %es */
  93   16 * 8,                       /* %fs */
  94   15 * 8                        /* %gs */
  95 };
  96
  97 static void
  98 amd64nbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
  99 {
 100   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 101
 102   /* Initialize general-purpose register set details first.  */
 103   tdep->gregset_reg_offset = amd64nbsd_r_reg_offset;
 104   tdep->gregset_num_regs = ARRAY_SIZE (amd64nbsd_r_reg_offset);
 105   tdep->sizeof_gregset = 26 * 8;
 106
 107   amd64_init_abi (info, gdbarch,
 108                   amd64_target_description (X86_XSTATE_SSE_MASK, true));
 109
 110   tdep->jb_pc_offset = 7 * 8;
 111
 112   /* NetBSD has its own convention for signal trampolines.  */
 113   tdep->sigtramp_p = amd64nbsd_sigtramp_p;
 114   tdep->sigcontext_addr = amd64nbsd_mcontext_addr;
 115   tdep->sc_reg_offset = amd64nbsd_r_reg_offset;
 116   tdep->sc_num_regs = ARRAY_SIZE (amd64nbsd_r_reg_offset);
 117
 118   /* NetBSD uses SVR4-style shared libraries.  */
 119   set_solib_svr4_fetch_link_map_offsets
 120     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 121 }
 122
 123 void
 124 _initialize_amd64nbsd_tdep (void)
 125 {
 126   /* The NetBSD/amd64 native dependent code makes this assumption.  */
 127   gdb_assert (ARRAY_SIZE (amd64nbsd_r_reg_offset) == AMD64_NUM_GREGS);
 128
 129   gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
 130                           GDB_OSABI_NETBSD, amd64nbsd_init_abi);
 131 }