gdb/alpha-bsd-nat.c

   1 /* Native-dependent code for Alpha BSD's.
   2
   3    Copyright (C) 2000-2020 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 /* We define this to get types like register_t.  */
  21 #define _KERNTYPES
  22 #include "defs.h"
  23 #include "inferior.h"
  24 #include "regcache.h"
  25
  26 #include "alpha-tdep.h"
  27 #include "alpha-bsd-tdep.h"
  28 #include "inf-ptrace.h"
  29 #include "nbsd-nat.h"
  30
  31 #include <sys/types.h>
  32 #include <sys/ptrace.h>
  33 #include <machine/reg.h>
  34
  35 struct alpha_bsd_nat_target final : public nbsd_nat_target
  36 {
  37   void fetch_registers (struct regcache *, int) override;
  38   void store_registers (struct regcache *, int) override;
  39 };
  40
  41 static alpha_bsd_nat_target the_alpha_bsd_nat_target;
  42
  43 /* Determine if PT_GETREGS fetches this register.  */
  44
  45 static int
  46 getregs_supplies (int regno)
  47 {
  48   return ((regno >= ALPHA_V0_REGNUM && regno <= ALPHA_ZERO_REGNUM)
  49           || regno >= ALPHA_PC_REGNUM);
  50 }
  51
  52 /* Fetch register REGNO from the inferior.  If REGNO is -1, do this
  53    for all registers (including the floating point registers).  */
  54
  55 void
  56 alpha_bsd_nat_target::fetch_registers (struct regcache *regcache, int regno)
  57 {
  58   int lwp = regcache->ptid ().lwp ();
  59
  60   if (regno == -1 || getregs_supplies (regno))
  61     {
  62       struct reg gregs;
  63
  64       if (ptrace (PT_GETREGS, regcache->ptid ().pid (),
  65                   (PTRACE_TYPE_ARG3) &gregs, lwp) == -1)
  66         perror_with_name (_("Couldn't get registers"));
  67
  68       alphabsd_supply_reg (regcache, (char *) &gregs, regno);
  69       if (regno != -1)
  70         return;
  71     }
  72
  73   if (regno == -1
  74       || regno >= gdbarch_fp0_regnum (regcache->arch ()))
  75     {
  76       struct fpreg fpregs;
  77
  78       if (ptrace (PT_GETFPREGS, regcache->ptid ().pid (),
  79                   (PTRACE_TYPE_ARG3) &fpregs, lwp) == -1)
  80         perror_with_name (_("Couldn't get floating point status"));
  81
  82       alphabsd_supply_fpreg (regcache, (char *) &fpregs, regno);
  83     }
  84 }
  85
  86 /* Store register REGNO back into the inferior.  If REGNO is -1, do
  87    this for all registers (including the floating point registers).  */
  88
  89 void
  90 alpha_bsd_nat_target::store_registers (struct regcache *regcache, int regno)
  91 {
  92   int lwp = regcache->ptid ().lwp ();
  93
  94   if (regno == -1 || getregs_supplies (regno))
  95     {
  96       struct reg gregs;
  97       if (ptrace (PT_GETREGS, regcache->ptid ().pid (),
  98                   (PTRACE_TYPE_ARG3) &gregs, lwp) == -1)
  99         perror_with_name (_("Couldn't get registers"));
 100
 101       alphabsd_fill_reg (regcache, (char *) &gregs, regno);
 102
 103       if (ptrace (PT_SETREGS, regcache->ptid ().pid (),
 104                   (PTRACE_TYPE_ARG3) &gregs, lwp) == -1)
 105         perror_with_name (_("Couldn't write registers"));
 106
 107       if (regno != -1)
 108         return;
 109     }
 110
 111   if (regno == -1
 112       || regno >= gdbarch_fp0_regnum (regcache->arch ()))
 113     {
 114       struct fpreg fpregs;
 115
 116       if (ptrace (PT_GETFPREGS, regcache->ptid ().pid (),
 117                   (PTRACE_TYPE_ARG3) &fpregs, lwp) == -1)
 118         perror_with_name (_("Couldn't get floating point status"));
 119
 120       alphabsd_fill_fpreg (regcache, (char *) &fpregs, regno);
 121
 122       if (ptrace (PT_SETFPREGS, regcache->ptid ().pid (),
 123                   (PTRACE_TYPE_ARG3) &fpregs, lwp) == -1)
 124         perror_with_name (_("Couldn't write floating point status"));
 125     }
 126 }
 127 \f
 128
 129 /* Support for debugging kernel virtual memory images.  */
 130
 131 #include <sys/signal.h>
 132 #include <machine/pcb.h>
 133
 134 #include "bsd-kvm.h"
 135
 136 static int
 137 alphabsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 138 {
 139   int regnum;
 140
 141   /* The following is true for OpenBSD 3.9:
 142
 143      The pcb contains the register state at the context switch inside
 144      cpu_switch().  */
 145
 146   /* The stack pointer shouldn't be zero.  */
 147   if (pcb->pcb_hw.apcb_ksp == 0)
 148     return 0;
 149
 150   regcache->raw_supply (ALPHA_SP_REGNUM, &pcb->pcb_hw.apcb_ksp);
 151
 152   for (regnum = ALPHA_S0_REGNUM; regnum < ALPHA_A0_REGNUM; regnum++)
 153     regcache->raw_supply (regnum, &pcb->pcb_context[regnum - ALPHA_S0_REGNUM]);
 154   regcache->raw_supply (ALPHA_RA_REGNUM, &pcb->pcb_context[7]);
 155
 156   return 1;
 157 }
 158 \f
 159
 160 void _initialize_alphabsd_nat ();
 161 void
 162 _initialize_alphabsd_nat ()
 163 {
 164   add_inf_child_target (&the_alpha_bsd_nat_target);
 165
 166   /* Support debugging kernel virtual memory images.  */
 167   bsd_kvm_add_target (alphabsd_supply_pcb);
 168 }