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
  36 /* The syscall's XML filename for sparc 64-bit.  */
  37 #define XML_SYSCALL_FILENAME_SPARC64 "syscalls/sparc64-linux.xml"
  38
  39 #include "sparc64-tdep.h"
  40
  41 /* Signal trampoline support.  */
  42
  43 static void sparc64_linux_sigframe_init (const struct tramp_frame *self,
  44                                          struct frame_info *this_frame,
  45                                          struct trad_frame_cache *this_cache,
  46                                          CORE_ADDR func);
  47
  48 /* See sparc-linux-tdep.c for details.  Note that 64-bit binaries only
  49    use RT signals.  */
  50
  51 static const struct tramp_frame sparc64_linux_rt_sigframe =
  52 {
  53   SIGTRAMP_FRAME,
  54   4,
  55   {
  56     { 0x82102065, -1 },         /* mov __NR_rt_sigreturn, %g1 */
  57     { 0x91d0206d, -1 },         /* ta  0x6d */
  58     { TRAMP_SENTINEL_INSN, -1 }
  59   },
  60   sparc64_linux_sigframe_init
  61 };
  62
  63 static void
  64 sparc64_linux_sigframe_init (const struct tramp_frame *self,
  65                              struct frame_info *this_frame,
  66                              struct trad_frame_cache *this_cache,
  67                              CORE_ADDR func)
  68 {
  69   CORE_ADDR base, addr, sp_addr;
  70   int regnum;
  71
  72   base = get_frame_register_unsigned (this_frame, SPARC_O1_REGNUM);
  73   base += 128;
  74
  75   /* Offsets from <bits/sigcontext.h>.  */
  76
  77   /* Since %g0 is always zero, keep the identity encoding.  */
  78   addr = base + 8;
  79   sp_addr = base + ((SPARC_SP_REGNUM - SPARC_G0_REGNUM) * 8);
  80   for (regnum = SPARC_G1_REGNUM; regnum <= SPARC_O7_REGNUM; regnum++)
  81     {
  82       trad_frame_set_reg_addr (this_cache, regnum, addr);
  83       addr += 8;
  84     }
  85
  86   trad_frame_set_reg_addr (this_cache, SPARC64_STATE_REGNUM, addr + 0);
  87   trad_frame_set_reg_addr (this_cache, SPARC64_PC_REGNUM, addr + 8);
  88   trad_frame_set_reg_addr (this_cache, SPARC64_NPC_REGNUM, addr + 16);
  89   trad_frame_set_reg_addr (this_cache, SPARC64_Y_REGNUM, addr + 24);
  90   trad_frame_set_reg_addr (this_cache, SPARC64_FPRS_REGNUM, addr + 28);
  91
  92   base = get_frame_register_unsigned (this_frame, SPARC_SP_REGNUM);
  93   if (base & 1)
  94     base += BIAS;
  95
  96   addr = get_frame_memory_unsigned (this_frame, sp_addr, 8);
  97   if (addr & 1)
  98     addr += BIAS;
  99
 100   for (regnum = SPARC_L0_REGNUM; regnum <= SPARC_I7_REGNUM; regnum++)
 101     {
 102       trad_frame_set_reg_addr (this_cache, regnum, addr);
 103       addr += 8;
 104     }
 105   trad_frame_set_id (this_cache, frame_id_build (base, func));
 106 }
 107 \f
 108 /* Return the address of a system call's alternative return
 109    address.  */
 110
 111 static CORE_ADDR
 112 sparc64_linux_step_trap (struct frame_info *frame, unsigned long insn)
 113 {
 114   if (insn == 0x91d0206d)
 115     {
 116       struct gdbarch *gdbarch = get_frame_arch (frame);
 117       enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
 118
 119       ULONGEST sp = get_frame_register_unsigned (frame, SPARC_SP_REGNUM);
 120       if (sp & 1)
 121         sp += BIAS;
 122
 123       /* The kernel puts the sigreturn registers on the stack,
 124          and this is where the signal unwinding state is take from
 125          when returning from a signal.
 126
 127          A siginfo_t sits 192 bytes from the base of the stack.  This
 128          siginfo_t is 128 bytes, and is followed by the sigreturn
 129          register save area.  The saved PC sits at a 136 byte offset
 130          into there.  */
 131
 132       return read_memory_unsigned_integer (sp + 192 + 128 + 136,
 133                                            8, byte_order);
 134     }
 135
 136   return 0;
 137 }
 138 \f
 139
 140 const struct sparc_gregset sparc64_linux_core_gregset =
 141 {
 142   32 * 8,                       /* %tstate */
 143   33 * 8,                       /* %tpc */
 144   34 * 8,                       /* %tnpc */
 145   35 * 8,                       /* %y */
 146   -1,                           /* %wim */
 147   -1,                           /* %tbr */
 148   1 * 8,                        /* %g1 */
 149   16 * 8,                       /* %l0 */
 150   8,                            /* y size */
 151 };
 152 \f
 153
 154 static void
 155 sparc64_linux_supply_core_gregset (const struct regset *regset,
 156                                    struct regcache *regcache,
 157                                    int regnum, const void *gregs, size_t len)
 158 {
 159   sparc64_supply_gregset (&sparc64_linux_core_gregset, regcache, regnum, gregs);
 160 }
 161
 162 static void
 163 sparc64_linux_collect_core_gregset (const struct regset *regset,
 164                                     const struct regcache *regcache,
 165                                     int regnum, void *gregs, size_t len)
 166 {
 167   sparc64_collect_gregset (&sparc64_linux_core_gregset, regcache, regnum, gregs);
 168 }
 169
 170 static void
 171 sparc64_linux_supply_core_fpregset (const struct regset *regset,
 172                                     struct regcache *regcache,
 173                                     int regnum, const void *fpregs, size_t len)
 174 {
 175   sparc64_supply_fpregset (regcache, regnum, fpregs);
 176 }
 177
 178 static void
 179 sparc64_linux_collect_core_fpregset (const struct regset *regset,
 180                                      const struct regcache *regcache,
 181                                      int regnum, void *fpregs, size_t len)
 182 {
 183   sparc64_collect_fpregset (regcache, regnum, fpregs);
 184 }
 185
 186 /* Set the program counter for process PTID to PC.  */
 187
 188 #define TSTATE_SYSCALL  0x0000000000000020ULL
 189
 190 static void
 191 sparc64_linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
 192 {
 193   struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
 194   ULONGEST state;
 195
 196   regcache_cooked_write_unsigned (regcache, tdep->pc_regnum, pc);
 197   regcache_cooked_write_unsigned (regcache, tdep->npc_regnum, pc + 4);
 198
 199   /* Clear the "in syscall" bit to prevent the kernel from
 200      messing with the PCs we just installed, if we happen to be
 201      within an interrupted system call that the kernel wants to
 202      restart.
 203
 204      Note that after we return from the dummy call, the TSTATE et al.
 205      registers will be automatically restored, and the kernel
 206      continues to restart the system call at this point.  */
 207   regcache_cooked_read_unsigned (regcache, SPARC64_STATE_REGNUM, &state);
 208   state &= ~TSTATE_SYSCALL;
 209   regcache_cooked_write_unsigned (regcache, SPARC64_STATE_REGNUM, state);
 210 }
 211
 212 static LONGEST
 213 sparc64_linux_get_syscall_number (struct gdbarch *gdbarch,
 214                                   ptid_t ptid)
 215 {
 216   struct regcache *regcache = get_thread_regcache (ptid);
 217   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
 218   /* The content of a register.  */
 219   gdb_byte buf[8];
 220   /* The result.  */
 221   LONGEST ret;
 222
 223   /* Getting the system call number from the register.
 224      When dealing with the sparc architecture, this information
 225      is stored at the %g1 register.  */
 226   regcache_cooked_read (regcache, SPARC_G1_REGNUM, buf);
 227
 228   ret = extract_signed_integer (buf, 8, byte_order);
 229
 230   return ret;
 231 }
 232
 233 \f
 234
 235 static void
 236 sparc64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 237 {
 238   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 239
 240   tdep->gregset = regset_alloc (gdbarch, sparc64_linux_supply_core_gregset,
 241                                 sparc64_linux_collect_core_gregset);
 242   tdep->sizeof_gregset = 288;
 243
 244   tdep->fpregset = regset_alloc (gdbarch, sparc64_linux_supply_core_fpregset,
 245                                  sparc64_linux_collect_core_fpregset);
 246   tdep->sizeof_fpregset = 280;
 247
 248   tramp_frame_prepend_unwinder (gdbarch, &sparc64_linux_rt_sigframe);
 249
 250   /* Hook in the DWARF CFI frame unwinder.  */
 251   dwarf2_append_unwinders (gdbarch);
 252
 253   sparc64_init_abi (info, gdbarch);
 254
 255   /* GNU/Linux has SVR4-style shared libraries...  */
 256   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
 257   set_solib_svr4_fetch_link_map_offsets
 258     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 259
 260   /* ...which means that we need some special handling when doing
 261      prologue analysis.  */
 262   tdep->plt_entry_size = 16;
 263
 264   /* Enable TLS support.  */
 265   set_gdbarch_fetch_tls_load_module_address (gdbarch,
 266                                              svr4_fetch_objfile_link_map);
 267
 268   /* Make sure we can single-step over signal return system calls.  */
 269   tdep->step_trap = sparc64_linux_step_trap;
 270
 271   set_gdbarch_write_pc (gdbarch, sparc64_linux_write_pc);
 272
 273   /* Functions for 'catch syscall'.  */
 274   set_xml_syscall_file_name (XML_SYSCALL_FILENAME_SPARC64);
 275   set_gdbarch_get_syscall_number (gdbarch,
 276                                   sparc64_linux_get_syscall_number);
 277 }
 278 \f
 279
 280 /* Provide a prototype to silence -Wmissing-prototypes.  */
 281 extern void _initialize_sparc64_linux_tdep (void);
 282
 283 void
 284 _initialize_sparc64_linux_tdep (void)
 285 {
 286   gdbarch_register_osabi (bfd_arch_sparc, bfd_mach_sparc_v9,
 287                           GDB_OSABI_LINUX, sparc64_linux_init_abi);
 288 }