gdb/sparc64-linux-tdep.c

   1 /* Target-dependent code for GNU/Linux UltraSPARC.
   2
   3    Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
   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,
 161                           regcache, regnum, gregs);
 162 }
 163
 164 static void
 165 sparc64_linux_collect_core_gregset (const struct regset *regset,
 166                                     const struct regcache *regcache,
 167                                     int regnum, void *gregs, size_t len)
 168 {
 169   sparc64_collect_gregset (&sparc64_linux_core_gregset,
 170                            regcache, regnum, gregs);
 171 }
 172
 173 static void
 174 sparc64_linux_supply_core_fpregset (const struct regset *regset,
 175                                     struct regcache *regcache,
 176                                     int regnum, const void *fpregs, size_t len)
 177 {
 178   sparc64_supply_fpregset (regcache, regnum, fpregs);
 179 }
 180
 181 static void
 182 sparc64_linux_collect_core_fpregset (const struct regset *regset,
 183                                      const struct regcache *regcache,
 184                                      int regnum, void *fpregs, size_t len)
 185 {
 186   sparc64_collect_fpregset (regcache, regnum, fpregs);
 187 }
 188
 189 /* Set the program counter for process PTID to PC.  */
 190
 191 #define TSTATE_SYSCALL  0x0000000000000020ULL
 192
 193 static void
 194 sparc64_linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
 195 {
 196   struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
 197   ULONGEST state;
 198
 199   regcache_cooked_write_unsigned (regcache, tdep->pc_regnum, pc);
 200   regcache_cooked_write_unsigned (regcache, tdep->npc_regnum, pc + 4);
 201
 202   /* Clear the "in syscall" bit to prevent the kernel from
 203      messing with the PCs we just installed, if we happen to be
 204      within an interrupted system call that the kernel wants to
 205      restart.
 206
 207      Note that after we return from the dummy call, the TSTATE et al.
 208      registers will be automatically restored, and the kernel
 209      continues to restart the system call at this point.  */
 210   regcache_cooked_read_unsigned (regcache, SPARC64_STATE_REGNUM, &state);
 211   state &= ~TSTATE_SYSCALL;
 212   regcache_cooked_write_unsigned (regcache, SPARC64_STATE_REGNUM, state);
 213 }
 214
 215 static LONGEST
 216 sparc64_linux_get_syscall_number (struct gdbarch *gdbarch,
 217                                   ptid_t ptid)
 218 {
 219   struct regcache *regcache = get_thread_regcache (ptid);
 220   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
 221   /* The content of a register.  */
 222   gdb_byte buf[8];
 223   /* The result.  */
 224   LONGEST ret;
 225
 226   /* Getting the system call number from the register.
 227      When dealing with the sparc architecture, this information
 228      is stored at the %g1 register.  */
 229   regcache_cooked_read (regcache, SPARC_G1_REGNUM, buf);
 230
 231   ret = extract_signed_integer (buf, 8, byte_order);
 232
 233   return ret;
 234 }
 235
 236 \f
 237
 238 static void
 239 sparc64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 240 {
 241   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 242
 243   linux_init_abi (info, gdbarch);
 244
 245   tdep->gregset = regset_alloc (gdbarch, sparc64_linux_supply_core_gregset,
 246                                 sparc64_linux_collect_core_gregset);
 247   tdep->sizeof_gregset = 288;
 248
 249   tdep->fpregset = regset_alloc (gdbarch, sparc64_linux_supply_core_fpregset,
 250                                  sparc64_linux_collect_core_fpregset);
 251   tdep->sizeof_fpregset = 280;
 252
 253   tramp_frame_prepend_unwinder (gdbarch, &sparc64_linux_rt_sigframe);
 254
 255   /* Hook in the DWARF CFI frame unwinder.  */
 256   dwarf2_append_unwinders (gdbarch);
 257
 258   sparc64_init_abi (info, gdbarch);
 259
 260   /* GNU/Linux has SVR4-style shared libraries...  */
 261   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
 262   set_solib_svr4_fetch_link_map_offsets
 263     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 264
 265   /* ...which means that we need some special handling when doing
 266      prologue analysis.  */
 267   tdep->plt_entry_size = 16;
 268
 269   /* Enable TLS support.  */
 270   set_gdbarch_fetch_tls_load_module_address (gdbarch,
 271                                              svr4_fetch_objfile_link_map);
 272
 273   /* Make sure we can single-step over signal return system calls.  */
 274   tdep->step_trap = sparc64_linux_step_trap;
 275
 276   set_gdbarch_write_pc (gdbarch, sparc64_linux_write_pc);
 277
 278   /* Functions for 'catch syscall'.  */
 279   set_xml_syscall_file_name (XML_SYSCALL_FILENAME_SPARC64);
 280   set_gdbarch_get_syscall_number (gdbarch,
 281                                   sparc64_linux_get_syscall_number);
 282 }
 283 \f
 284
 285 /* Provide a prototype to silence -Wmissing-prototypes.  */
 286 extern void _initialize_sparc64_linux_tdep (void);
 287
 288 void
 289 _initialize_sparc64_linux_tdep (void)
 290 {
 291   gdbarch_register_osabi (bfd_arch_sparc, bfd_mach_sparc_v9,
 292                           GDB_OSABI_LINUX, sparc64_linux_init_abi);
 293 }