gdb/sparc64-linux-tdep.c

   1 /* Target-dependent code for GNU/Linux UltraSPARC.
   2
   3    Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "defs.h"
  22 #include "frame.h"
  23 #include "frame-unwind.h"
  24 #include "dwarf2-frame.h"
  25 #include "regset.h"
  26 #include "regcache.h"
  27 #include "gdbarch.h"
  28 #include "gdbcore.h"
  29 #include "osabi.h"
  30 #include "solib-svr4.h"
  31 #include "symtab.h"
  32 #include "trad-frame.h"
  33 #include "tramp-frame.h"
  34 #include "xml-syscall.h"
  35 #include "linux-tdep.h"
  36
  37 /* The syscall's XML filename for sparc 64-bit.  */
  38 #define XML_SYSCALL_FILENAME_SPARC64 "syscalls/sparc64-linux.xml"
  39
  40 #include "sparc64-tdep.h"
  41
  42 /* Signal trampoline support.  */
  43
  44 static void sparc64_linux_sigframe_init (const struct tramp_frame *self,
  45                                          struct frame_info *this_frame,
  46                                          struct trad_frame_cache *this_cache,
  47                                          CORE_ADDR func);
  48
  49 /* See sparc-linux-tdep.c for details.  Note that 64-bit binaries only
  50    use RT signals.  */
  51
  52 static const struct tramp_frame sparc64_linux_rt_sigframe =
  53 {
  54   SIGTRAMP_FRAME,
  55   4,
  56   {
  57     { 0x82102065, -1 },         /* mov __NR_rt_sigreturn, %g1 */
  58     { 0x91d0206d, -1 },         /* ta  0x6d */
  59     { TRAMP_SENTINEL_INSN, -1 }
  60   },
  61   sparc64_linux_sigframe_init
  62 };
  63
  64 static void
  65 sparc64_linux_sigframe_init (const struct tramp_frame *self,
  66                              struct frame_info *this_frame,
  67                              struct trad_frame_cache *this_cache,
  68                              CORE_ADDR func)
  69 {
  70   CORE_ADDR base, addr, sp_addr;
  71   int regnum;
  72
  73   base = get_frame_register_unsigned (this_frame, SPARC_O1_REGNUM);
  74   base += 128;
  75
  76   /* Offsets from <bits/sigcontext.h>.  */
  77
  78   /* Since %g0 is always zero, keep the identity encoding.  */
  79   addr = base + 8;
  80   sp_addr = base + ((SPARC_SP_REGNUM - SPARC_G0_REGNUM) * 8);
  81   for (regnum = SPARC_G1_REGNUM; regnum <= SPARC_O7_REGNUM; regnum++)
  82     {
  83       trad_frame_set_reg_addr (this_cache, regnum, addr);
  84       addr += 8;
  85     }
  86
  87   trad_frame_set_reg_addr (this_cache, SPARC64_STATE_REGNUM, addr + 0);
  88   trad_frame_set_reg_addr (this_cache, SPARC64_PC_REGNUM, addr + 8);
  89   trad_frame_set_reg_addr (this_cache, SPARC64_NPC_REGNUM, addr + 16);
  90   trad_frame_set_reg_addr (this_cache, SPARC64_Y_REGNUM, addr + 24);
  91   trad_frame_set_reg_addr (this_cache, SPARC64_FPRS_REGNUM, addr + 28);
  92
  93   base = get_frame_register_unsigned (this_frame, SPARC_SP_REGNUM);
  94   if (base & 1)
  95     base += BIAS;
  96
  97   addr = get_frame_memory_unsigned (this_frame, sp_addr, 8);
  98   if (addr & 1)
  99     addr += BIAS;
 100
 101   for (regnum = SPARC_L0_REGNUM; regnum <= SPARC_I7_REGNUM; regnum++)
 102     {
 103       trad_frame_set_reg_addr (this_cache, regnum, addr);
 104       addr += 8;
 105     }
 106   trad_frame_set_id (this_cache, frame_id_build (base, func));
 107 }
 108 \f
 109 /* Return the address of a system call's alternative return
 110    address.  */
 111
 112 static CORE_ADDR
 113 sparc64_linux_step_trap (struct frame_info *frame, unsigned long insn)
 114 {
 115   if (insn == 0x91d0206d)
 116     {
 117       struct gdbarch *gdbarch = get_frame_arch (frame);
 118       enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
 119
 120       ULONGEST sp = get_frame_register_unsigned (frame, SPARC_SP_REGNUM);
 121       if (sp & 1)
 122         sp += BIAS;
 123
 124       /* The kernel puts the sigreturn registers on the stack,
 125          and this is where the signal unwinding state is take from
 126          when returning from a signal.
 127
 128          A siginfo_t sits 192 bytes from the base of the stack.  This
 129          siginfo_t is 128 bytes, and is followed by the sigreturn
 130          register save area.  The saved PC sits at a 136 byte offset
 131          into there.  */
 132
 133       return read_memory_unsigned_integer (sp + 192 + 128 + 136,
 134                                            8, byte_order);
 135     }
 136
 137   return 0;
 138 }
 139 \f
 140
 141 const struct sparc_gregset sparc64_linux_core_gregset =
 142 {
 143   32 * 8,                       /* %tstate */
 144   33 * 8,                       /* %tpc */
 145   34 * 8,                       /* %tnpc */
 146   35 * 8,                       /* %y */
 147   -1,                           /* %wim */
 148   -1,                           /* %tbr */
 149   1 * 8,                        /* %g1 */
 150   16 * 8,                       /* %l0 */
 151   8,                            /* y size */
 152 };
 153 \f
 154
 155 static void
 156 sparc64_linux_supply_core_gregset (const struct regset *regset,
 157                                    struct regcache *regcache,
 158                                    int regnum, const void *gregs, size_t len)
 159 {
 160   sparc64_supply_gregset (&sparc64_linux_core_gregset, regcache, regnum, gregs);
 161 }
 162
 163 static void
 164 sparc64_linux_collect_core_gregset (const struct regset *regset,
 165                                     const struct regcache *regcache,
 166                                     int regnum, void *gregs, size_t len)
 167 {
 168   sparc64_collect_gregset (&sparc64_linux_core_gregset, regcache, regnum, gregs);
 169 }
 170
 171 static void
 172 sparc64_linux_supply_core_fpregset (const struct regset *regset,
 173                                     struct regcache *regcache,
 174                                     int regnum, const void *fpregs, size_t len)
 175 {
 176   sparc64_supply_fpregset (regcache, regnum, fpregs);
 177 }
 178
 179 static void
 180 sparc64_linux_collect_core_fpregset (const struct regset *regset,
 181                                      const struct regcache *regcache,
 182                                      int regnum, void *fpregs, size_t len)
 183 {
 184   sparc64_collect_fpregset (regcache, regnum, fpregs);
 185 }
 186
 187 /* Set the program counter for process PTID to PC.  */
 188
 189 #define TSTATE_SYSCALL  0x0000000000000020ULL
 190
 191 static void
 192 sparc64_linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
 193 {
 194   struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
 195   ULONGEST state;
 196
 197   regcache_cooked_write_unsigned (regcache, tdep->pc_regnum, pc);
 198   regcache_cooked_write_unsigned (regcache, tdep->npc_regnum, pc + 4);
 199
 200   /* Clear the "in syscall" bit to prevent the kernel from
 201      messing with the PCs we just installed, if we happen to be
 202      within an interrupted system call that the kernel wants to
 203      restart.
 204
 205      Note that after we return from the dummy call, the TSTATE et al.
 206      registers will be automatically restored, and the kernel
 207      continues to restart the system call at this point.  */
 208   regcache_cooked_read_unsigned (regcache, SPARC64_STATE_REGNUM, &state);
 209   state &= ~TSTATE_SYSCALL;
 210   regcache_cooked_write_unsigned (regcache, SPARC64_STATE_REGNUM, state);
 211 }
 212
 213 static LONGEST
 214 sparc64_linux_get_syscall_number (struct gdbarch *gdbarch,
 215                                   ptid_t ptid)
 216 {
 217   struct regcache *regcache = get_thread_regcache (ptid);
 218   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
 219   /* The content of a register.  */
 220   gdb_byte buf[8];
 221   /* The result.  */
 222   LONGEST ret;
 223
 224   /* Getting the system call number from the register.
 225      When dealing with the sparc architecture, this information
 226      is stored at the %g1 register.  */
 227   regcache_cooked_read (regcache, SPARC_G1_REGNUM, buf);
 228
 229   ret = extract_signed_integer (buf, 8, byte_order);
 230
 231   return ret;
 232 }
 233
 234 \f
 235
 236 static void
 237 sparc64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 238 {
 239   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 240
 241   linux_init_abi (info, gdbarch);
 242
 243   tdep->gregset = regset_alloc (gdbarch, sparc64_linux_supply_core_gregset,
 244                                 sparc64_linux_collect_core_gregset);
 245   tdep->sizeof_gregset = 288;
 246
 247   tdep->fpregset = regset_alloc (gdbarch, sparc64_linux_supply_core_fpregset,
 248                                  sparc64_linux_collect_core_fpregset);
 249   tdep->sizeof_fpregset = 280;
 250
 251   tramp_frame_prepend_unwinder (gdbarch, &sparc64_linux_rt_sigframe);
 252
 253   /* Hook in the DWARF CFI frame unwinder.  */
 254   dwarf2_append_unwinders (gdbarch);
 255
 256   sparc64_init_abi (info, gdbarch);
 257
 258   /* GNU/Linux has SVR4-style shared libraries...  */
 259   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
 260   set_solib_svr4_fetch_link_map_offsets
 261     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 262
 263   /* ...which means that we need some special handling when doing
 264      prologue analysis.  */
 265   tdep->plt_entry_size = 16;
 266
 267   /* Enable TLS support.  */
 268   set_gdbarch_fetch_tls_load_module_address (gdbarch,
 269                                              svr4_fetch_objfile_link_map);
 270
 271   /* Make sure we can single-step over signal return system calls.  */
 272   tdep->step_trap = sparc64_linux_step_trap;
 273
 274   set_gdbarch_write_pc (gdbarch, sparc64_linux_write_pc);
 275
 276   /* Functions for 'catch syscall'.  */
 277   set_xml_syscall_file_name (XML_SYSCALL_FILENAME_SPARC64);
 278   set_gdbarch_get_syscall_number (gdbarch,
 279                                   sparc64_linux_get_syscall_number);
 280 }
 281 \f
 282
 283 /* Provide a prototype to silence -Wmissing-prototypes.  */
 284 extern void _initialize_sparc64_linux_tdep (void);
 285
 286 void
 287 _initialize_sparc64_linux_tdep (void)
 288 {
 289   gdbarch_register_osabi (bfd_arch_sparc, bfd_mach_sparc_v9,
 290                           GDB_OSABI_LINUX, sparc64_linux_init_abi);
 291 }