gdb/sparc64-linux-tdep.c

   1 /* Target-dependent code for GNU/Linux UltraSPARC.
   2
   3    Copyright (C) 2003-2022 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 "frame.h"
  22 #include "frame-unwind.h"
  23 #include "dwarf2/frame.h"
  24 #include "regset.h"
  25 #include "regcache.h"
  26 #include "gdbarch.h"
  27 #include "gdbcore.h"
  28 #include "osabi.h"
  29 #include "solib-svr4.h"
  30 #include "symtab.h"
  31 #include "trad-frame.h"
  32 #include "tramp-frame.h"
  33 #include "xml-syscall.h"
  34 #include "linux-tdep.h"
  35
  36 /* ADI specific si_code */
  37 #ifndef SEGV_ACCADI
  38 #define SEGV_ACCADI     3
  39 #endif
  40 #ifndef SEGV_ADIDERR
  41 #define SEGV_ADIDERR    4
  42 #endif
  43 #ifndef SEGV_ADIPERR
  44 #define SEGV_ADIPERR    5
  45 #endif
  46
  47 /* The syscall's XML filename for sparc 64-bit.  */
  48 #define XML_SYSCALL_FILENAME_SPARC64 "syscalls/sparc64-linux.xml"
  49
  50 #include "sparc64-tdep.h"
  51
  52 /* Signal trampoline support.  */
  53
  54 static void sparc64_linux_sigframe_init (const struct tramp_frame *self,
  55                                          struct frame_info *this_frame,
  56                                          struct trad_frame_cache *this_cache,
  57                                          CORE_ADDR func);
  58
  59 /* See sparc-linux-tdep.c for details.  Note that 64-bit binaries only
  60    use RT signals.  */
  61
  62 static const struct tramp_frame sparc64_linux_rt_sigframe =
  63 {
  64   SIGTRAMP_FRAME,
  65   4,
  66   {
  67     { 0x82102065, ULONGEST_MAX },               /* mov __NR_rt_sigreturn, %g1 */
  68     { 0x91d0206d, ULONGEST_MAX },               /* ta  0x6d */
  69     { TRAMP_SENTINEL_INSN, ULONGEST_MAX }
  70   },
  71   sparc64_linux_sigframe_init
  72 };
  73
  74 static void
  75 sparc64_linux_sigframe_init (const struct tramp_frame *self,
  76                              struct frame_info *this_frame,
  77                              struct trad_frame_cache *this_cache,
  78                              CORE_ADDR func)
  79 {
  80   CORE_ADDR base, addr, sp_addr;
  81   int regnum;
  82
  83   base = get_frame_register_unsigned (this_frame, SPARC_O1_REGNUM);
  84   base += 128;
  85
  86   /* Offsets from <bits/sigcontext.h>.  */
  87
  88   /* Since %g0 is always zero, keep the identity encoding.  */
  89   addr = base + 8;
  90   sp_addr = base + ((SPARC_SP_REGNUM - SPARC_G0_REGNUM) * 8);
  91   for (regnum = SPARC_G1_REGNUM; regnum <= SPARC_O7_REGNUM; regnum++)
  92     {
  93       trad_frame_set_reg_addr (this_cache, regnum, addr);
  94       addr += 8;
  95     }
  96
  97   trad_frame_set_reg_addr (this_cache, SPARC64_STATE_REGNUM, addr + 0);
  98   trad_frame_set_reg_addr (this_cache, SPARC64_PC_REGNUM, addr + 8);
  99   trad_frame_set_reg_addr (this_cache, SPARC64_NPC_REGNUM, addr + 16);
 100   trad_frame_set_reg_addr (this_cache, SPARC64_Y_REGNUM, addr + 24);
 101   trad_frame_set_reg_addr (this_cache, SPARC64_FPRS_REGNUM, addr + 28);
 102
 103   base = get_frame_register_unsigned (this_frame, SPARC_SP_REGNUM);
 104   if (base & 1)
 105     base += BIAS;
 106
 107   addr = get_frame_memory_unsigned (this_frame, sp_addr, 8);
 108   if (addr & 1)
 109     addr += BIAS;
 110
 111   for (regnum = SPARC_L0_REGNUM; regnum <= SPARC_I7_REGNUM; regnum++)
 112     {
 113       trad_frame_set_reg_addr (this_cache, regnum, addr);
 114       addr += 8;
 115     }
 116   trad_frame_set_id (this_cache, frame_id_build (base, func));
 117 }
 118
 119 /* sparc64 GNU/Linux implementation of the report_signal_info
 120    gdbarch hook.
 121    Displays information related to ADI memory corruptions.  */
 122
 123 static void
 124 sparc64_linux_report_signal_info (struct gdbarch *gdbarch, struct ui_out *uiout,
 125                                   enum gdb_signal siggnal)
 126 {
 127   if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word != 64
 128       || siggnal != GDB_SIGNAL_SEGV)
 129     return;
 130
 131   CORE_ADDR addr = 0;
 132   long si_code = 0;
 133
 134   try
 135     {
 136       /* Evaluate si_code to see if the segfault is ADI related.  */
 137       si_code = parse_and_eval_long ("$_siginfo.si_code\n");
 138
 139       if (si_code >= SEGV_ACCADI && si_code <= SEGV_ADIPERR)
 140         addr = parse_and_eval_long ("$_siginfo._sifields._sigfault.si_addr");
 141     }
 142   catch (const gdb_exception &exception)
 143     {
 144       return;
 145     }
 146
 147   /* Print out ADI event based on sig_code value */
 148   switch (si_code)
 149     {
 150     case SEGV_ACCADI:   /* adi not enabled */
 151       uiout->text ("\n");
 152       uiout->field_string ("sigcode-meaning", _("ADI disabled"));
 153       uiout->text (_(" while accessing address "));
 154       uiout->field_core_addr ("bound-access", gdbarch, addr);
 155       break;
 156     case SEGV_ADIDERR:  /* disrupting mismatch */
 157       uiout->text ("\n");
 158       uiout->field_string ("sigcode-meaning", _("ADI deferred mismatch"));
 159       uiout->text (_(" while accessing address "));
 160       uiout->field_core_addr ("bound-access", gdbarch, addr);
 161       break;
 162     case SEGV_ADIPERR:  /* precise mismatch */
 163       uiout->text ("\n");
 164       uiout->field_string ("sigcode-meaning", _("ADI precise mismatch"));
 165       uiout->text (_(" while accessing address "));
 166       uiout->field_core_addr ("bound-access", gdbarch, addr);
 167       break;
 168     default:
 169       break;
 170     }
 171
 172 }
 173
 174 \f
 175 /* Return the address of a system call's alternative return
 176    address.  */
 177
 178 static CORE_ADDR
 179 sparc64_linux_step_trap (struct frame_info *frame, unsigned long insn)
 180 {
 181   /* __NR_rt_sigreturn is 101  */
 182   if ((insn == 0x91d0206d)
 183       && (get_frame_register_unsigned (frame, SPARC_G1_REGNUM) == 101))
 184     {
 185       struct gdbarch *gdbarch = get_frame_arch (frame);
 186       enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
 187
 188       ULONGEST sp = get_frame_register_unsigned (frame, SPARC_SP_REGNUM);
 189       if (sp & 1)
 190         sp += BIAS;
 191
 192       /* The kernel puts the sigreturn registers on the stack,
 193          and this is where the signal unwinding state is take from
 194          when returning from a signal.
 195
 196          A siginfo_t sits 192 bytes from the base of the stack.  This
 197          siginfo_t is 128 bytes, and is followed by the sigreturn
 198          register save area.  The saved PC sits at a 136 byte offset
 199          into there.  */
 200
 201       return read_memory_unsigned_integer (sp + 192 + 128 + 136,
 202                                            8, byte_order);
 203     }
 204
 205   return 0;
 206 }
 207 \f
 208
 209 const struct sparc_gregmap sparc64_linux_core_gregmap =
 210 {
 211   32 * 8,                       /* %tstate */
 212   33 * 8,                       /* %tpc */
 213   34 * 8,                       /* %tnpc */
 214   35 * 8,                       /* %y */
 215   -1,                           /* %wim */
 216   -1,                           /* %tbr */
 217   1 * 8,                        /* %g1 */
 218   16 * 8,                       /* %l0 */
 219   8,                            /* y size */
 220 };
 221 \f
 222
 223 static void
 224 sparc64_linux_supply_core_gregset (const struct regset *regset,
 225                                    struct regcache *regcache,
 226                                    int regnum, const void *gregs, size_t len)
 227 {
 228   sparc64_supply_gregset (&sparc64_linux_core_gregmap,
 229                           regcache, regnum, gregs);
 230 }
 231
 232 static void
 233 sparc64_linux_collect_core_gregset (const struct regset *regset,
 234                                     const struct regcache *regcache,
 235                                     int regnum, void *gregs, size_t len)
 236 {
 237   sparc64_collect_gregset (&sparc64_linux_core_gregmap,
 238                            regcache, regnum, gregs);
 239 }
 240
 241 static void
 242 sparc64_linux_supply_core_fpregset (const struct regset *regset,
 243                                     struct regcache *regcache,
 244                                     int regnum, const void *fpregs, size_t len)
 245 {
 246   sparc64_supply_fpregset (&sparc64_bsd_fpregmap, regcache, regnum, fpregs);
 247 }
 248
 249 static void
 250 sparc64_linux_collect_core_fpregset (const struct regset *regset,
 251                                      const struct regcache *regcache,
 252                                      int regnum, void *fpregs, size_t len)
 253 {
 254   sparc64_collect_fpregset (&sparc64_bsd_fpregmap, regcache, regnum, fpregs);
 255 }
 256
 257 /* Set the program counter for process PTID to PC.  */
 258
 259 #define TSTATE_SYSCALL  0x0000000000000020ULL
 260
 261 static void
 262 sparc64_linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
 263 {
 264   gdbarch *arch = regcache->arch ();
 265   sparc_gdbarch_tdep *tdep = (sparc_gdbarch_tdep *) gdbarch_tdep (arch);
 266   ULONGEST state;
 267
 268   regcache_cooked_write_unsigned (regcache, tdep->pc_regnum, pc);
 269   regcache_cooked_write_unsigned (regcache, tdep->npc_regnum, pc + 4);
 270
 271   /* Clear the "in syscall" bit to prevent the kernel from
 272      messing with the PCs we just installed, if we happen to be
 273      within an interrupted system call that the kernel wants to
 274      restart.
 275
 276      Note that after we return from the dummy call, the TSTATE et al.
 277      registers will be automatically restored, and the kernel
 278      continues to restart the system call at this point.  */
 279   regcache_cooked_read_unsigned (regcache, SPARC64_STATE_REGNUM, &state);
 280   state &= ~TSTATE_SYSCALL;
 281   regcache_cooked_write_unsigned (regcache, SPARC64_STATE_REGNUM, state);
 282 }
 283
 284 static LONGEST
 285 sparc64_linux_get_syscall_number (struct gdbarch *gdbarch,
 286                                   thread_info *thread)
 287 {
 288   struct regcache *regcache = get_thread_regcache (thread);
 289   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
 290   /* The content of a register.  */
 291   gdb_byte buf[8];
 292   /* The result.  */
 293   LONGEST ret;
 294
 295   /* Getting the system call number from the register.
 296      When dealing with the sparc architecture, this information
 297      is stored at the %g1 register.  */
 298   regcache->cooked_read (SPARC_G1_REGNUM, buf);
 299
 300   ret = extract_signed_integer (buf, 8, byte_order);
 301
 302   return ret;
 303 }
 304
 305 \f
 306 /* Implement the "get_longjmp_target" gdbarch method.  */
 307
 308 static int
 309 sparc64_linux_get_longjmp_target (struct frame_info *frame, CORE_ADDR *pc)
 310 {
 311   struct gdbarch *gdbarch = get_frame_arch (frame);
 312   CORE_ADDR jb_addr;
 313   gdb_byte buf[8];
 314
 315   jb_addr = get_frame_register_unsigned (frame, SPARC_O0_REGNUM);
 316
 317   /* setjmp and longjmp in SPARC64 are implemented in glibc using the
 318      setcontext and getcontext system calls respectively.  These
 319      system calls operate on ucontext_t structures, which happen to
 320      partially have the same structure than jmp_buf.  However the
 321      ucontext returned by getcontext, and thus the jmp_buf structure
 322      returned by setjmp, contains the context of the trap instruction
 323      in the glibc __[sig]setjmp wrapper, not the context of the user
 324      code calling setjmp.
 325
 326      %o7 in the jmp_buf structure is stored at offset 18*8 in the
 327      mc_gregs array, which is itself located at offset 32 into
 328      jmp_buf.  See bits/setjmp.h.  This register contains the address
 329      of the 'call setjmp' instruction in user code.
 330
 331      In order to determine the longjmp target address in the
 332      initiating frame we need to examine the call instruction itself,
 333      in particular whether the annul bit is set.  If it is not set
 334      then we need to jump over the instruction at the delay slot.  */
 335
 336   if (target_read_memory (jb_addr + 32 + (18 * 8), buf, 8))
 337     return 0;
 338
 339   *pc = extract_unsigned_integer (buf, 8, gdbarch_byte_order (gdbarch));
 340
 341   if (!sparc_is_annulled_branch_insn (*pc))
 342       *pc += 4; /* delay slot insn  */
 343   *pc += 4; /* call insn  */
 344
 345   return 1;
 346 }
 347
 348 \f
 349
 350 static const struct regset sparc64_linux_gregset =
 351   {
 352     NULL,
 353     sparc64_linux_supply_core_gregset,
 354     sparc64_linux_collect_core_gregset
 355   };
 356
 357 static const struct regset sparc64_linux_fpregset =
 358   {
 359     NULL,
 360     sparc64_linux_supply_core_fpregset,
 361     sparc64_linux_collect_core_fpregset
 362   };
 363
 364 static void
 365 sparc64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 366 {
 367   sparc_gdbarch_tdep *tdep = (sparc_gdbarch_tdep *) gdbarch_tdep (gdbarch);
 368
 369   linux_init_abi (info, gdbarch, 0);
 370
 371   tdep->gregset = &sparc64_linux_gregset;
 372   tdep->sizeof_gregset = 288;
 373
 374   tdep->fpregset = &sparc64_linux_fpregset;
 375   tdep->sizeof_fpregset = 280;
 376
 377   tramp_frame_prepend_unwinder (gdbarch, &sparc64_linux_rt_sigframe);
 378
 379   /* Hook in the DWARF CFI frame unwinder.  */
 380   dwarf2_append_unwinders (gdbarch);
 381
 382   sparc64_init_abi (info, gdbarch);
 383
 384   /* GNU/Linux has SVR4-style shared libraries...  */
 385   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
 386   set_solib_svr4_fetch_link_map_offsets
 387     (gdbarch, linux_lp64_fetch_link_map_offsets);
 388
 389   /* ...which means that we need some special handling when doing
 390      prologue analysis.  */
 391   tdep->plt_entry_size = 16;
 392
 393   /* Enable TLS support.  */
 394   set_gdbarch_fetch_tls_load_module_address (gdbarch,
 395                                              svr4_fetch_objfile_link_map);
 396
 397   /* Make sure we can single-step over signal return system calls.  */
 398   tdep->step_trap = sparc64_linux_step_trap;
 399
 400   /* Make sure we can single-step over longjmp calls.  */
 401   set_gdbarch_get_longjmp_target (gdbarch, sparc64_linux_get_longjmp_target);
 402
 403   set_gdbarch_write_pc (gdbarch, sparc64_linux_write_pc);
 404
 405   /* Functions for 'catch syscall'.  */
 406   set_xml_syscall_file_name (gdbarch, XML_SYSCALL_FILENAME_SPARC64);
 407   set_gdbarch_get_syscall_number (gdbarch,
 408                                   sparc64_linux_get_syscall_number);
 409   set_gdbarch_report_signal_info (gdbarch, sparc64_linux_report_signal_info);
 410 }
 411
 412 void _initialize_sparc64_linux_tdep ();
 413 void
 414 _initialize_sparc64_linux_tdep ()
 415 {
 416   gdbarch_register_osabi (bfd_arch_sparc, bfd_mach_sparc_v9,
 417                           GDB_OSABI_LINUX, sparc64_linux_init_abi);
 418 }