gdb/sparc64-linux-tdep.c

   1 /* Target-dependent code for GNU/Linux UltraSPARC.
   2
   3    Copyright (C) 2003, 2004, 2005, 2007, 2008 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 "frame.h"
  22 #include "frame-unwind.h"
  23 #include "dwarf2-frame.h"
  24 #include "regset.h"
  25 #include "regcache.h"
  26 #include "gdbarch.h"
  27 #include "gdbcore.h"
  28 #include "osabi.h"
  29 #include "solib-svr4.h"
  30 #include "symtab.h"
  31 #include "trad-frame.h"
  32 #include "tramp-frame.h"
  33
  34 #include "sparc64-tdep.h"
  35
  36 /* Signal trampoline support.  */
  37
  38 static void sparc64_linux_sigframe_init (const struct tramp_frame *self,
  39                                          struct frame_info *next_frame,
  40                                          struct trad_frame_cache *this_cache,
  41                                          CORE_ADDR func);
  42
  43 /* See sparc-linux-tdep.c for details.  Note that 64-bit binaries only
  44    use RT signals.  */
  45
  46 static const struct tramp_frame sparc64_linux_rt_sigframe =
  47 {
  48   SIGTRAMP_FRAME,
  49   4,
  50   {
  51     { 0x82102065, -1 },         /* mov __NR_rt_sigreturn, %g1 */
  52     { 0x91d0206d, -1 },         /* ta  0x6d */
  53     { TRAMP_SENTINEL_INSN, -1 }
  54   },
  55   sparc64_linux_sigframe_init
  56 };
  57
  58 static void
  59 sparc64_linux_sigframe_init (const struct tramp_frame *self,
  60                              struct frame_info *next_frame,
  61                              struct trad_frame_cache *this_cache,
  62                              CORE_ADDR func)
  63 {
  64   CORE_ADDR base, addr, sp_addr;
  65   int regnum;
  66
  67   base = frame_unwind_register_unsigned (next_frame, SPARC_O1_REGNUM);
  68   base += 128;
  69
  70   /* Offsets from <bits/sigcontext.h>.  */
  71
  72   /* Since %g0 is always zero, keep the identity encoding.  */
  73   addr = base + 8;
  74   sp_addr = base + ((SPARC_SP_REGNUM - SPARC_G0_REGNUM) * 8);
  75   for (regnum = SPARC_G1_REGNUM; regnum <= SPARC_O7_REGNUM; regnum++)
  76     {
  77       trad_frame_set_reg_addr (this_cache, regnum, addr);
  78       addr += 8;
  79     }
  80
  81   trad_frame_set_reg_addr (this_cache, SPARC64_STATE_REGNUM, addr + 0);
  82   trad_frame_set_reg_addr (this_cache, SPARC64_PC_REGNUM, addr + 8);
  83   trad_frame_set_reg_addr (this_cache, SPARC64_NPC_REGNUM, addr + 16);
  84   trad_frame_set_reg_addr (this_cache, SPARC64_Y_REGNUM, addr + 24);
  85   trad_frame_set_reg_addr (this_cache, SPARC64_FPRS_REGNUM, addr + 28);
  86
  87   base = frame_unwind_register_unsigned (next_frame, SPARC_SP_REGNUM);
  88   if (base & 1)
  89     base += BIAS;
  90
  91   addr = get_frame_memory_unsigned (next_frame, sp_addr, 8);
  92   if (addr & 1)
  93     addr += BIAS;
  94
  95   for (regnum = SPARC_L0_REGNUM; regnum <= SPARC_I7_REGNUM; regnum++)
  96     {
  97       trad_frame_set_reg_addr (this_cache, regnum, addr);
  98       addr += 8;
  99     }
 100   trad_frame_set_id (this_cache, frame_id_build (base, func));
 101 }
 102 \f
 103 /* Return the address of a system call's alternative return
 104    address.  */
 105
 106 static CORE_ADDR
 107 sparc64_linux_step_trap (struct frame_info *frame, unsigned long insn)
 108 {
 109   if (insn == 0x91d0206d)
 110     {
 111       ULONGEST sp = get_frame_register_unsigned (frame, SPARC_SP_REGNUM);
 112       if (sp & 1)
 113         sp += BIAS;
 114
 115       /* The kernel puts the sigreturn registers on the stack,
 116          and this is where the signal unwinding state is take from
 117          when returning from a signal.
 118
 119          A siginfo_t sits 192 bytes from the base of the stack.  This
 120          siginfo_t is 128 bytes, and is followed by the sigreturn
 121          register save area.  The saved PC sits at a 136 byte offset
 122          into there.  */
 123
 124       return read_memory_unsigned_integer (sp + 192 + 128 + 136, 8);
 125     }
 126
 127   return 0;
 128 }
 129 \f
 130
 131 const struct sparc_gregset sparc64_linux_core_gregset =
 132 {
 133   32 * 8,                       /* %tstate */
 134   33 * 8,                       /* %tpc */
 135   34 * 8,                       /* %tnpc */
 136   35 * 8,                       /* %y */
 137   -1,                           /* %wim */
 138   -1,                           /* %tbr */
 139   1 * 8,                        /* %g1 */
 140   16 * 8,                       /* %l0 */
 141   8,                            /* y size */
 142 };
 143 \f
 144
 145 static void
 146 sparc64_linux_supply_core_gregset (const struct regset *regset,
 147                                    struct regcache *regcache,
 148                                    int regnum, const void *gregs, size_t len)
 149 {
 150   sparc64_supply_gregset (&sparc64_linux_core_gregset, regcache, regnum, gregs);
 151 }
 152
 153 static void
 154 sparc64_linux_collect_core_gregset (const struct regset *regset,
 155                                     const struct regcache *regcache,
 156                                     int regnum, void *gregs, size_t len)
 157 {
 158   sparc64_collect_gregset (&sparc64_linux_core_gregset, regcache, regnum, gregs);
 159 }
 160
 161 static void
 162 sparc64_linux_supply_core_fpregset (const struct regset *regset,
 163                                     struct regcache *regcache,
 164                                     int regnum, const void *fpregs, size_t len)
 165 {
 166   sparc64_supply_fpregset (regcache, regnum, fpregs);
 167 }
 168
 169 static void
 170 sparc64_linux_collect_core_fpregset (const struct regset *regset,
 171                                      const struct regcache *regcache,
 172                                      int regnum, void *fpregs, size_t len)
 173 {
 174   sparc64_collect_fpregset (regcache, regnum, fpregs);
 175 }
 176
 177 \f
 178
 179 static void
 180 sparc64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 181 {
 182   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 183
 184   tdep->gregset = regset_alloc (gdbarch, sparc64_linux_supply_core_gregset,
 185                                 sparc64_linux_collect_core_gregset);
 186   tdep->sizeof_gregset = 288;
 187
 188   tdep->fpregset = regset_alloc (gdbarch, sparc64_linux_supply_core_fpregset,
 189                                  sparc64_linux_collect_core_fpregset);
 190   tdep->sizeof_fpregset = 280;
 191
 192   tramp_frame_prepend_unwinder (gdbarch, &sparc64_linux_rt_sigframe);
 193
 194   /* Hook in the DWARF CFI frame unwinder.  */
 195   frame_unwind_append_sniffer (gdbarch, dwarf2_frame_sniffer);
 196
 197   sparc64_init_abi (info, gdbarch);
 198
 199   /* GNU/Linux has SVR4-style shared libraries...  */
 200   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
 201   set_solib_svr4_fetch_link_map_offsets
 202     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 203
 204   /* ...which means that we need some special handling when doing
 205      prologue analysis.  */
 206   tdep->plt_entry_size = 16;
 207
 208   /* Enable TLS support.  */
 209   set_gdbarch_fetch_tls_load_module_address (gdbarch,
 210                                              svr4_fetch_objfile_link_map);
 211
 212   /* Make sure we can single-step over signal return system calls.  */
 213   tdep->step_trap = sparc64_linux_step_trap;
 214 }
 215 \f
 216
 217 /* Provide a prototype to silence -Wmissing-prototypes.  */
 218 extern void _initialize_sparc64_linux_tdep (void);
 219
 220 void
 221 _initialize_sparc64_linux_tdep (void)
 222 {
 223   gdbarch_register_osabi (bfd_arch_sparc, bfd_mach_sparc_v9,
 224                           GDB_OSABI_LINUX, sparc64_linux_init_abi);
 225 }