gdb/ppcfbsd-tdep.c - gdb

Global variables defined

Functions defined

Source code

  1. /* Target-dependent code for PowerPC systems running FreeBSD.

  3.    Copyright (C) 2013-2015 Free Software Foundation, Inc.

  5.    This file is part of GDB.

  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.

  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.

  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/>.  */

  20. #include "defs.h"
  21. #include "arch-utils.h"
  22. #include "frame.h"
  23. #include "gdbcore.h"
  24. #include "frame-unwind.h"
  25. #include "gdbtypes.h"
  26. #include "osabi.h"
  27. #include "regcache.h"
  28. #include "regset.h"
  29. #include "symtab.h"
  30. #include "target.h"
  31. #include "trad-frame.h"

  33. #include "ppc-tdep.h"
  34. #include "ppc64-tdep.h"
  35. #include "ppcfbsd-tdep.h"
  36. #include "fbsd-tdep.h"
  37. #include "solib-svr4.h"


  40. /* 32-bit regset descriptions.  */

  42. ‌static const struct ppc_reg_offsets ppc32_fbsd_reg_offsets =
  43.   {
  44.         /* General-purpose registers.  */
  45.         /* .r0_offset = */     0,
  46.         /* .gpr_size = */      4,
  47.         /* .xr_size = */       4,
  48.         /* .pc_offset = */     144,
  49.         /* .ps_offset = */     -1,
  50.         /* .cr_offset = */     132,
  51.         /* .lr_offset = */     128,
  52.         /* .ctr_offset = */    140,
  53.         /* .xer_offset = */    136,
  54.         /* .mq_offset = */     -1,

  56.         /* Floating-point registers.  */
  57.         /* .f0_offset = */     0,
  58.         /* .fpscr_offset = */  256,
  59.         /* .fpscr_size = */    8,
  60. #ifdef NOTYET
  61.         /* AltiVec registers.  */
  62.         /* .vr0_offset = */    0,
  63.         /* .vscr_offset = */   512 + 12,
  64.         /* .vrsave_offset = */ 512
  65. #endif
  66.   };

  68. /* 64-bit regset descriptions.  */

  70. ‌static const struct ppc_reg_offsets ppc64_fbsd_reg_offsets =
  71.   {
  72.         /* General-purpose registers.  */
  73.         /* .r0_offset = */     0,
  74.         /* .gpr_size = */      8,
  75.         /* .xr_size = */       8,
  76.         /* .pc_offset = */     288,
  77.         /* .ps_offset = */     -1,
  78.         /* .cr_offset = */     264,
  79.         /* .lr_offset = */     256,
  80.         /* .ctr_offset = */    280,
  81.         /* .xer_offset = */    272,
  82.         /* .mq_offset = */     -1,

  84.         /* Floating-point registers.  */
  85.         /* .f0_offset = */     0,
  86.         /* .fpscr_offset = */  256,
  87.         /* .fpscr_size = */    8,
  88. #ifdef NOYET
  89.         /* AltiVec registers.  */
  90.         /* .vr0_offset = */    0,
  91.         /* .vscr_offset = */   512 + 12,
  92.         /* .vrsave_offset = */ 528
  93. #endif
  94.   };

  96. /* 32-bit general-purpose register set.  */

  98. ‌static const struct regset ppc32_fbsd_gregset = {
  99.   &ppc32_fbsd_reg_offsets,
  100.   ppc_supply_gregset,
  101.   ppc_collect_gregset
  102. };

  104. /* 64-bit general-purpose register set.  */

  106. ‌static const struct regset ppc64_fbsd_gregset = {
  107.   &ppc64_fbsd_reg_offsets,
  108.   ppc_supply_gregset,
  109.   ppc_collect_gregset
  110. };

  112. /* 32-/64-bit floating-point register set.  */

  114. ‌static const struct regset ppc32_fbsd_fpregset = {
  115.   &ppc32_fbsd_reg_offsets,
  116.   ppc_supply_fpregset,
  117.   ppc_collect_fpregset
  118. };

  120. const struct regset *
  121. ‌ppc_fbsd_gregset (int wordsize)
  122. {
  123.   return wordsize == 8 ? &ppc64_fbsd_gregset : &ppc32_fbsd_gregset;
  124. }

  126. const struct regset *
  127. ‌ppc_fbsd_fpregset (void)
  128. {
  129.   return &ppc32_fbsd_fpregset;
  130. }

  132. /* Iterate over core file register note sections.  */

  134. static void
  135. ‌ppcfbsd_iterate_over_regset_sections (struct gdbarch *gdbarch,
  136.                                       iterate_over_regset_sections_cb *cb,
  137.                                       void *cb_data,
  138.                                       const struct regcache *regcache)
  139. {
  140.   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  142.   if (tdep->wordsize == 4)
  143.     cb (".reg", 148, &ppc32_fbsd_gregset, NULL, cb_data);
  144.   else
  145.     cb (".reg", 296, &ppc64_fbsd_gregset, NULL, cb_data);
  146.   cb (".reg2", 264, &ppc32_fbsd_fpregset, NULL, cb_data);
  147. }

  149. /* Default page size.  */

  151. ‌static const int ppcfbsd_page_size = 4096;

  153. /* Offset for sigreturn(2).  */

  155. ‌static const int ppcfbsd_sigreturn_offset[] = {
  156.   0xc,                                /* FreeBSD 32-bit  */
  157.   -1
  158. };

  160. /* Signal trampolines.  */

  162. static int
  163. ‌ppcfbsd_sigtramp_frame_sniffer (const struct frame_unwind *self,
  164.                                 struct frame_info *this_frame,
  165.                                 void **this_cache)
  166. {
  167.   struct gdbarch *gdbarch = get_frame_arch (this_frame);
  168.   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
  169.   CORE_ADDR pc = get_frame_pc (this_frame);
  170.   CORE_ADDR start_pc = (pc & ~(ppcfbsd_page_size - 1));
  171.   const int *offset;
  172.   const char *name;

  174.   /* A stack trampoline is detected if no name is associated
  175.    to the current pc and if it points inside a trampoline
  176.    sequence.  */

  178.   find_pc_partial_function (pc, &name, NULL, NULL);

  180.   /* If we have a name, we have no trampoline, return.  */
  181.   if (name)
  182.     return 0;

  184.   for (offset = ppcfbsd_sigreturn_offset; *offset != -1; offset++)
  185.     {
  186.       gdb_byte buf[2 * PPC_INSN_SIZE];
  187.       unsigned long insn;

  189.       if (!safe_frame_unwind_memory (this_frame, start_pc + *offset,
  190.                                      buf, sizeof buf))
  191.         continue;

  193.       /* Check for "li r0,SYS_sigreturn".  */
  194.       insn = extract_unsigned_integer (buf, PPC_INSN_SIZE, byte_order);
  195.       if (insn != 0x380001a1)
  196.         continue;

  198.       /* Check for "sc".  */
  199.       insn = extract_unsigned_integer (buf + PPC_INSN_SIZE,
  200.                                        PPC_INSN_SIZE, byte_order);
  201.       if (insn != 0x44000002)
  202.         continue;

  204.       return 1;
  205.     }

  207.   return 0;
  208. }

  210. static struct trad_frame_cache *
  211. ‌ppcfbsd_sigtramp_frame_cache (struct frame_info *this_frame, void **this_cache)
  212. {
  213.   struct gdbarch *gdbarch = get_frame_arch (this_frame);
  214.   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  215.   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
  216.   struct trad_frame_cache *cache;
  217.   CORE_ADDR addr, base, func;
  218.   gdb_byte buf[PPC_INSN_SIZE];
  219.   int i;

  221.   if (*this_cache)
  222.     return *this_cache;

  224.   cache = trad_frame_cache_zalloc (this_frame);
  225.   *this_cache = cache;

  227.   func = get_frame_pc (this_frame);
  228.   func &= ~(ppcfbsd_page_size - 1);
  229.   if (!safe_frame_unwind_memory (this_frame, func, buf, sizeof buf))
  230.     return cache;

  232.   base = get_frame_register_unsigned (this_frame, gdbarch_sp_regnum (gdbarch));
  233.   addr = base + 0x10 + 2 * tdep->wordsize;
  234.   for (i = 0; i < ppc_num_gprs; i++, addr += tdep->wordsize)
  235.     {
  236.       int regnum = i + tdep->ppc_gp0_regnum;
  237.       trad_frame_set_reg_addr (cache, regnum, addr);
  238.     }
  239.   trad_frame_set_reg_addr (cache, tdep->ppc_lr_regnum, addr);
  240.   addr += tdep->wordsize;
  241.   trad_frame_set_reg_addr (cache, tdep->ppc_cr_regnum, addr);
  242.   addr += tdep->wordsize;
  243.   trad_frame_set_reg_addr (cache, tdep->ppc_xer_regnum, addr);
  244.   addr += tdep->wordsize;
  245.   trad_frame_set_reg_addr (cache, tdep->ppc_ctr_regnum, addr);
  246.   addr += tdep->wordsize;
  247.   trad_frame_set_reg_addr (cache, gdbarch_pc_regnum (gdbarch), addr);
  248.   /* SRR0?  */
  249.   addr += tdep->wordsize;

  251.   /* Construct the frame ID using the function start.  */
  252.   trad_frame_set_id (cache, frame_id_build (base, func));

  254.   return cache;
  255. }

  257. static void
  258. ‌ppcfbsd_sigtramp_frame_this_id (struct frame_info *this_frame,
  259.                                 void **this_cache, struct frame_id *this_id)
  260. {
  261.   struct trad_frame_cache *cache =
  262.     ppcfbsd_sigtramp_frame_cache (this_frame, this_cache);

  264.   trad_frame_get_id (cache, this_id);
  265. }

  267. static struct value *
  268. ‌ppcfbsd_sigtramp_frame_prev_register (struct frame_info *this_frame,
  269.                                       void **this_cache, int regnum)
  270. {
  271.   struct trad_frame_cache *cache =
  272.     ppcfbsd_sigtramp_frame_cache (this_frame, this_cache);

  274.   return trad_frame_get_register (cache, this_frame, regnum);
  275. }

  277. ‌static const struct frame_unwind ppcfbsd_sigtramp_frame_unwind = {
  278.   SIGTRAMP_FRAME,
  279.   default_frame_unwind_stop_reason,
  280.   ppcfbsd_sigtramp_frame_this_id,
  281.   ppcfbsd_sigtramp_frame_prev_register,
  282.   NULL,
  283.   ppcfbsd_sigtramp_frame_sniffer
  284. };

  286. static enum return_value_convention
  287. ‌ppcfbsd_return_value (struct gdbarch *gdbarch, struct value *function,
  288.                       struct type *valtype, struct regcache *regcache,
  289.                       gdb_byte *readbuf, const gdb_byte *writebuf)
  290. {
  291.   return ppc_sysv_abi_broken_return_value (gdbarch, function, valtype,
  292.                                            regcache, readbuf, writebuf);
  293. }


  296. static void
  297. ‌ppcfbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
  298. {
  299.   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  301.   /* Generic FreeBSD support. */
  302.   fbsd_init_abi (info, gdbarch);

  304.   /* FreeBSD doesn't support the 128-bit `long double' from the psABI.  */
  305.   set_gdbarch_long_double_bit (gdbarch, 64);
  306.   set_gdbarch_long_double_format (gdbarch, floatformats_ieee_double);

  308.   if (tdep->wordsize == 4)
  309.     {
  310.       set_gdbarch_return_value (gdbarch, ppcfbsd_return_value);

  312.       set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
  313.       set_solib_svr4_fetch_link_map_offsets (gdbarch,
  314.                                              svr4_ilp32_fetch_link_map_offsets);

  316.       frame_unwind_append_unwinder (gdbarch, &ppcfbsd_sigtramp_frame_unwind);
  317.       set_gdbarch_gcore_bfd_target (gdbarch, "elf32-powerpc");
  318.     }

  320.   if (tdep->wordsize == 8)
  321.     {
  322.       set_gdbarch_convert_from_func_ptr_addr
  323.         (gdbarch, ppc64_convert_from_func_ptr_addr);
  324.       set_gdbarch_elf_make_msymbol_special (gdbarch,
  325.                                             ppc64_elf_make_msymbol_special);

  327.       set_gdbarch_skip_trampoline_code (gdbarch, ppc64_skip_trampoline_code);
  328.       set_solib_svr4_fetch_link_map_offsets (gdbarch,
  329.                                              svr4_lp64_fetch_link_map_offsets);
  330.       set_gdbarch_gcore_bfd_target (gdbarch, "elf64-powerpc");
  331.     }

  333.   set_gdbarch_iterate_over_regset_sections
  334.     (gdbarch, ppcfbsd_iterate_over_regset_sections);

  336.   set_gdbarch_fetch_tls_load_module_address (gdbarch,
  337.                                              svr4_fetch_objfile_link_map);
  338. }

  340. /* Provide a prototype to silence -Wmissing-prototypes.  */

  342. void _initialize_ppcfbsd_tdep (void);

  344. void
  345. ‌_initialize_ppcfbsd_tdep (void)
  346. {
  347.   gdbarch_register_osabi (bfd_arch_powerpc, bfd_mach_ppc, GDB_OSABI_FREEBSD_ELF,
  348.                           ppcfbsd_init_abi);
  349.   gdbarch_register_osabi (bfd_arch_powerpc, bfd_mach_ppc64,
  350.                           GDB_OSABI_FREEBSD_ELF,
  351.                           ppcfbsd_init_abi);
  352.   gdbarch_register_osabi (bfd_arch_rs6000, 0, GDB_OSABI_FREEBSD_ELF,
  353.                           ppcfbsd_init_abi);
  354. }