gdb/sh-linux-tdep.c

   1 /* Target-dependent code for GNU/Linux Super-H.
   2
   3    Copyright (C) 2005-2015 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 "osabi.h"
  22
  23 #include "solib-svr4.h"
  24 #include "symtab.h"
  25
  26 #include "trad-frame.h"
  27 #include "tramp-frame.h"
  28
  29 #include "glibc-tdep.h"
  30 #include "sh-tdep.h"
  31 #include "linux-tdep.h"
  32
  33 #define REGSx16(base) \
  34   {(base),      0}, \
  35   {(base) +  1, 4}, \
  36   {(base) +  2, 8}, \
  37   {(base) +  3, 12}, \
  38   {(base) +  4, 16}, \
  39   {(base) +  5, 20}, \
  40   {(base) +  6, 24}, \
  41   {(base) +  7, 28}, \
  42   {(base) +  8, 32}, \
  43   {(base) +  9, 36}, \
  44   {(base) + 10, 40}, \
  45   {(base) + 11, 44}, \
  46   {(base) + 12, 48}, \
  47   {(base) + 13, 52}, \
  48   {(base) + 14, 56}, \
  49   {(base) + 15, 60}
  50
  51 /* Describe the contents of the .reg section of the core file.  */
  52
  53 static const struct sh_corefile_regmap gregs_table[] =
  54 {
  55   REGSx16 (R0_REGNUM),
  56   {PC_REGNUM,   64},
  57   {PR_REGNUM,   68},
  58   {SR_REGNUM,   72},
  59   {GBR_REGNUM,  76},
  60   {MACH_REGNUM, 80},
  61   {MACL_REGNUM, 84},
  62   {-1 /* Terminator.  */, 0}
  63 };
  64
  65 /* Describe the contents of the .reg2 section of the core file.  */
  66
  67 static const struct sh_corefile_regmap fpregs_table[] =
  68 {
  69   REGSx16 (FR0_REGNUM),
  70   /* REGSx16 xfp_regs omitted.  */
  71   {FPSCR_REGNUM, 128},
  72   {FPUL_REGNUM,  132},
  73   {-1 /* Terminator.  */, 0}
  74 };
  75
  76 /* SH signal handler frame support.  */
  77
  78 static void
  79 sh_linux_sigtramp_cache (struct frame_info *this_frame,
  80                          struct trad_frame_cache *this_cache,
  81                          CORE_ADDR func, int regs_offset)
  82 {
  83   int i;
  84   struct gdbarch *gdbarch = get_frame_arch (this_frame);
  85   CORE_ADDR base = get_frame_register_unsigned (this_frame,
  86                                                 gdbarch_sp_regnum (gdbarch));
  87   CORE_ADDR regs = base + regs_offset;
  88
  89   for (i = 0; i < 18; i++)
  90     trad_frame_set_reg_addr (this_cache, i, regs + i * 4);
  91
  92   trad_frame_set_reg_addr (this_cache, SR_REGNUM, regs + 18 * 4);
  93   trad_frame_set_reg_addr (this_cache, GBR_REGNUM, regs + 19 * 4);
  94   trad_frame_set_reg_addr (this_cache, MACH_REGNUM, regs + 20 * 4);
  95   trad_frame_set_reg_addr (this_cache, MACL_REGNUM, regs + 21 * 4);
  96
  97   /* Restore FP state if we have an FPU.  */
  98   if (gdbarch_fp0_regnum (gdbarch) != -1)
  99     {
 100       CORE_ADDR fpregs = regs + 22 * 4;
 101       for (i = FR0_REGNUM; i <= FP_LAST_REGNUM; i++)
 102         trad_frame_set_reg_addr (this_cache, i, fpregs + i * 4);
 103       trad_frame_set_reg_addr (this_cache, FPSCR_REGNUM, fpregs + 32 * 4);
 104       trad_frame_set_reg_addr (this_cache, FPUL_REGNUM, fpregs + 33 * 4);
 105     }
 106
 107   /* Save a frame ID.  */
 108   trad_frame_set_id (this_cache, frame_id_build (base, func));
 109 }
 110
 111 /* Implement struct tramp_frame "init" callbacks for signal
 112    trampolines on 32-bit SH.  */
 113
 114 static void
 115 sh_linux_sigreturn_init (const struct tramp_frame *self,
 116                          struct frame_info *this_frame,
 117                          struct trad_frame_cache *this_cache,
 118                          CORE_ADDR func)
 119 {
 120   /* SH 32-bit sigframe: sigcontext at start of sigframe,
 121      registers start after a single 'oldmask' word.  */
 122   sh_linux_sigtramp_cache (this_frame, this_cache, func, 4);
 123 }
 124
 125 static void
 126 sh_linux_rt_sigreturn_init (const struct tramp_frame *self,
 127                             struct frame_info *this_frame,
 128                             struct trad_frame_cache *this_cache,
 129                             CORE_ADDR func)
 130 {
 131   /* SH 32-bit rt_sigframe: starts with a siginfo (128 bytes), then
 132      we can find sigcontext embedded within a ucontext (offset 20 bytes).
 133      Then registers start after a single 'oldmask' word.  */
 134   sh_linux_sigtramp_cache (this_frame, this_cache, func,
 135                            128 /* sizeof (struct siginfo)  */
 136                            + 20 /* offsetof (struct ucontext, uc_mcontext) */
 137                            + 4 /* oldmask word at start of sigcontext */);
 138 }
 139
 140 /* Instruction patterns.  */
 141 #define SH_MOVW     0x9305
 142 #define SH_TRAP     0xc300
 143 #define SH_OR_R0_R0 0x200b
 144
 145 /* SH sigreturn syscall numbers.  */
 146 #define SH_NR_SIGRETURN 0x0077
 147 #define SH_NR_RT_SIGRETURN 0x00ad
 148
 149 static struct tramp_frame sh_linux_sigreturn_tramp_frame = {
 150   SIGTRAMP_FRAME,
 151   2,
 152   {
 153     { SH_MOVW, 0xffff },
 154     { SH_TRAP, 0xff00 }, /* #imm argument part filtered out.  */
 155     { SH_OR_R0_R0, 0xffff },
 156     { SH_OR_R0_R0, 0xffff },
 157     { SH_OR_R0_R0, 0xffff },
 158     { SH_OR_R0_R0, 0xffff },
 159     { SH_OR_R0_R0, 0xffff },
 160     { SH_NR_SIGRETURN, 0xffff },
 161     { TRAMP_SENTINEL_INSN }
 162   },
 163   sh_linux_sigreturn_init
 164 };
 165
 166 static struct tramp_frame sh_linux_rt_sigreturn_tramp_frame = {
 167   SIGTRAMP_FRAME,
 168   2,
 169   {
 170     { SH_MOVW, 0xffff },
 171     { SH_TRAP, 0xff00 }, /* #imm argument part filtered out.  */
 172     { SH_OR_R0_R0, 0xffff },
 173     { SH_OR_R0_R0, 0xffff },
 174     { SH_OR_R0_R0, 0xffff },
 175     { SH_OR_R0_R0, 0xffff },
 176     { SH_OR_R0_R0, 0xffff },
 177     { SH_NR_RT_SIGRETURN, 0xffff },
 178     { TRAMP_SENTINEL_INSN }
 179   },
 180   sh_linux_rt_sigreturn_init
 181 };
 182
 183 static void
 184 sh_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 185 {
 186   linux_init_abi (info, gdbarch);
 187
 188   /* GNU/Linux uses SVR4-style shared libraries.  */
 189   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
 190   set_solib_svr4_fetch_link_map_offsets
 191     (gdbarch, svr4_ilp32_fetch_link_map_offsets);
 192   set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
 193
 194   set_gdbarch_fetch_tls_load_module_address (gdbarch,
 195                                              svr4_fetch_objfile_link_map);
 196
 197   /* Core files and signal handler frame unwinding are supported for
 198      32-bit SH only, at present.  */
 199   if (info.bfd_arch_info->mach != bfd_mach_sh5)
 200     {
 201       struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 202
 203       /* Remember regset characteristics.  The sizes should match
 204          elf_gregset_t and elf_fpregset_t from Linux.  */
 205       tdep->core_gregmap = (struct sh_corefile_regmap *)gregs_table;
 206       tdep->sizeof_gregset = 92;
 207       tdep->core_fpregmap = (struct sh_corefile_regmap *)fpregs_table;
 208       tdep->sizeof_fpregset = 136;
 209
 210       tramp_frame_prepend_unwinder (gdbarch, &sh_linux_sigreturn_tramp_frame);
 211       tramp_frame_prepend_unwinder (gdbarch, &sh_linux_rt_sigreturn_tramp_frame);
 212     }
 213 }
 214
 215 /* Provide a prototype to silence -Wmissing-prototypes.  */
 216 extern void _initialize_sh_linux_tdep (void);
 217
 218 void
 219 _initialize_sh_linux_tdep (void)
 220 {
 221   gdbarch_register_osabi (bfd_arch_sh, 0, GDB_OSABI_LINUX, sh_linux_init_abi);
 222 }