gdb/sh-linux-tdep.c

   1 /* Target-dependent code for GNU/Linux Super-H.
   2
   3    Copyright (C) 2005-2023 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 #include "gdbarch.h"
  33
  34 #define REGSx16(base) \
  35   {(base),      0}, \
  36   {(base) +  1, 4}, \
  37   {(base) +  2, 8}, \
  38   {(base) +  3, 12}, \
  39   {(base) +  4, 16}, \
  40   {(base) +  5, 20}, \
  41   {(base) +  6, 24}, \
  42   {(base) +  7, 28}, \
  43   {(base) +  8, 32}, \
  44   {(base) +  9, 36}, \
  45   {(base) + 10, 40}, \
  46   {(base) + 11, 44}, \
  47   {(base) + 12, 48}, \
  48   {(base) + 13, 52}, \
  49   {(base) + 14, 56}, \
  50   {(base) + 15, 60}
  51
  52 /* Describe the contents of the .reg section of the core file.  */
  53
  54 static const struct sh_corefile_regmap gregs_table[] =
  55 {
  56   REGSx16 (R0_REGNUM),
  57   {PC_REGNUM,   64},
  58   {PR_REGNUM,   68},
  59   {SR_REGNUM,   72},
  60   {GBR_REGNUM,  76},
  61   {MACH_REGNUM, 80},
  62   {MACL_REGNUM, 84},
  63   {-1 /* Terminator.  */, 0}
  64 };
  65
  66 /* Describe the contents of the .reg2 section of the core file.  */
  67
  68 static const struct sh_corefile_regmap fpregs_table[] =
  69 {
  70   REGSx16 (FR0_REGNUM),
  71   /* REGSx16 xfp_regs omitted.  */
  72   {FPSCR_REGNUM, 128},
  73   {FPUL_REGNUM,  132},
  74   {-1 /* Terminator.  */, 0}
  75 };
  76
  77 /* SH signal handler frame support.  */
  78
  79 static void
  80 sh_linux_sigtramp_cache (frame_info_ptr this_frame,
  81                          struct trad_frame_cache *this_cache,
  82                          CORE_ADDR func, int regs_offset)
  83 {
  84   int i;
  85   struct gdbarch *gdbarch = get_frame_arch (this_frame);
  86   CORE_ADDR base = get_frame_register_unsigned (this_frame,
  87                                                 gdbarch_sp_regnum (gdbarch));
  88   CORE_ADDR regs = base + regs_offset;
  89
  90   for (i = 0; i < 18; i++)
  91     trad_frame_set_reg_addr (this_cache, i, regs + i * 4);
  92
  93   trad_frame_set_reg_addr (this_cache, SR_REGNUM, regs + 18 * 4);
  94   trad_frame_set_reg_addr (this_cache, GBR_REGNUM, regs + 19 * 4);
  95   trad_frame_set_reg_addr (this_cache, MACH_REGNUM, regs + 20 * 4);
  96   trad_frame_set_reg_addr (this_cache, MACL_REGNUM, regs + 21 * 4);
  97
  98   /* Restore FP state if we have an FPU.  */
  99   if (gdbarch_fp0_regnum (gdbarch) != -1)
 100     {
 101       CORE_ADDR fpregs = regs + 22 * 4;
 102       for (i = FR0_REGNUM; i <= FP_LAST_REGNUM; i++)
 103         trad_frame_set_reg_addr (this_cache, i, fpregs + i * 4);
 104       trad_frame_set_reg_addr (this_cache, FPSCR_REGNUM, fpregs + 32 * 4);
 105       trad_frame_set_reg_addr (this_cache, FPUL_REGNUM, fpregs + 33 * 4);
 106     }
 107
 108   /* Save a frame ID.  */
 109   trad_frame_set_id (this_cache, frame_id_build (base, func));
 110 }
 111
 112 /* Implement struct tramp_frame "init" callbacks for signal
 113    trampolines on 32-bit SH.  */
 114
 115 static void
 116 sh_linux_sigreturn_init (const struct tramp_frame *self,
 117                          frame_info_ptr this_frame,
 118                          struct trad_frame_cache *this_cache,
 119                          CORE_ADDR func)
 120 {
 121   /* SH 32-bit sigframe: sigcontext at start of sigframe,
 122      registers start after a single 'oldmask' word.  */
 123   sh_linux_sigtramp_cache (this_frame, this_cache, func, 4);
 124 }
 125
 126 static void
 127 sh_linux_rt_sigreturn_init (const struct tramp_frame *self,
 128                             frame_info_ptr this_frame,
 129                             struct trad_frame_cache *this_cache,
 130                             CORE_ADDR func)
 131 {
 132   /* SH 32-bit rt_sigframe: starts with a siginfo (128 bytes), then
 133      we can find sigcontext embedded within a ucontext (offset 20 bytes).
 134      Then registers start after a single 'oldmask' word.  */
 135   sh_linux_sigtramp_cache (this_frame, this_cache, func,
 136                            128 /* sizeof (struct siginfo)  */
 137                            + 20 /* offsetof (struct ucontext, uc_mcontext) */
 138                            + 4 /* oldmask word at start of sigcontext */);
 139 }
 140
 141 /* Instruction patterns.  */
 142 #define SH_MOVW     0x9305
 143 #define SH_TRAP     0xc300
 144 #define SH_OR_R0_R0 0x200b
 145
 146 /* SH sigreturn syscall numbers.  */
 147 #define SH_NR_SIGRETURN 0x0077
 148 #define SH_NR_RT_SIGRETURN 0x00ad
 149
 150 static struct tramp_frame sh_linux_sigreturn_tramp_frame = {
 151   SIGTRAMP_FRAME,
 152   2,
 153   {
 154     { SH_MOVW, 0xffff },
 155     { SH_TRAP, 0xff00 }, /* #imm argument part filtered out.  */
 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_OR_R0_R0, 0xffff },
 161     { SH_NR_SIGRETURN, 0xffff },
 162     { TRAMP_SENTINEL_INSN }
 163   },
 164   sh_linux_sigreturn_init
 165 };
 166
 167 static struct tramp_frame sh_linux_rt_sigreturn_tramp_frame = {
 168   SIGTRAMP_FRAME,
 169   2,
 170   {
 171     { SH_MOVW, 0xffff },
 172     { SH_TRAP, 0xff00 }, /* #imm argument part filtered out.  */
 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_OR_R0_R0, 0xffff },
 178     { SH_NR_RT_SIGRETURN, 0xffff },
 179     { TRAMP_SENTINEL_INSN }
 180   },
 181   sh_linux_rt_sigreturn_init
 182 };
 183
 184 static void
 185 sh_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 186 {
 187   linux_init_abi (info, gdbarch, 0);
 188
 189   /* GNU/Linux uses SVR4-style shared libraries.  */
 190   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
 191   set_solib_svr4_fetch_link_map_offsets
 192     (gdbarch, linux_ilp32_fetch_link_map_offsets);
 193   set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
 194
 195   set_gdbarch_fetch_tls_load_module_address (gdbarch,
 196                                              svr4_fetch_objfile_link_map);
 197
 198   sh_gdbarch_tdep *tdep = gdbarch_tdep<sh_gdbarch_tdep> (gdbarch);
 199
 200   /* Remember regset characteristics.  The sizes should match
 201      elf_gregset_t and elf_fpregset_t from Linux.  */
 202   tdep->core_gregmap = (struct sh_corefile_regmap *) gregs_table;
 203   tdep->sizeof_gregset = 92;
 204   tdep->core_fpregmap = (struct sh_corefile_regmap *) fpregs_table;
 205   tdep->sizeof_fpregset = 136;
 206
 207   tramp_frame_prepend_unwinder (gdbarch, &sh_linux_sigreturn_tramp_frame);
 208   tramp_frame_prepend_unwinder (gdbarch, &sh_linux_rt_sigreturn_tramp_frame);
 209 }
 210
 211 void _initialize_sh_linux_tdep ();
 212 void
 213 _initialize_sh_linux_tdep ()
 214 {
 215   gdbarch_register_osabi (bfd_arch_sh, 0, GDB_OSABI_LINUX, sh_linux_init_abi);
 216 }