gdb/tic6x-linux-tdep.c - gdb

Global variables defined

Functions defined

Macros defined

Source code

  1. /* GNU/Linux on  TI C6x target support.
  2.    Copyright (C) 2011-2015 Free Software Foundation, Inc.
  3.    Contributed by Yao Qi <yao@codesourcery.com>

  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 "solib.h"
  22. #include "osabi.h"
  23. #include "linux-tdep.h"
  24. #include "tic6x-tdep.h"
  25. #include "trad-frame.h"
  26. #include "tramp-frame.h"
  27. #include "elf-bfd.h"
  28. #include "elf/tic6x.h"

  30. #include "features/tic6x-c64xp-linux.c"
  31. #include "features/tic6x-c64x-linux.c"
  32. #include "features/tic6x-c62x-linux.c"

  34. /* The offset from rt_sigframe pointer to SP register.  */
  35. ‌#define TIC6X_SP_RT_SIGFRAME 8
  36. /* Size of struct siginfo info.  */
  37. ‌#define TIC6X_SIGINFO_SIZE 128
  38. /* Size of type stack_t, which contains three fields of type void*, int, and
  39.    size_t respectively.  */
  40. ‌#define TIC6X_STACK_T_SIZE (3 * 4)

  42. ‌static const gdb_byte tic6x_bkpt_bnop_be[] = { 0x00, 0x00, 0xa1, 0x22 };
  43. ‌static const gdb_byte tic6x_bkpt_bnop_le[] = { 0x22, 0xa1, 0x00, 0x00 };

  45. /* Return the offset of register REGNUM in struct sigcontext.  Return 0 if no
  46.    such register in sigcontext.  */

  48. static unsigned int
  49. ‌tic6x_register_sigcontext_offset (unsigned int regnum, struct gdbarch *gdbarch)
  50. {
  51.   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  53.   if (regnum == TIC6X_A4_REGNUM || regnum == TIC6X_A4_REGNUM + 2
  54.       || regnum == TIC6X_A4_REGNUM + 4)
  55.     return 4 * (regnum - TIC6X_A4_REGNUM + 2);        /* A4, A6, A8 */
  56.   else if (regnum == TIC6X_A5_REGNUM || regnum == TIC6X_A5_REGNUM + 2
  57.            || regnum == TIC6X_A5_REGNUM + 4)
  58.     return 4 * (regnum - TIC6X_A5_REGNUM + 12);        /* A5, A7, A9 */
  59.   else if (regnum == TIC6X_B4_REGNUM || regnum == TIC6X_B4_REGNUM + 2
  60.            || regnum == TIC6X_B4_REGNUM + 4)
  61.     return 4 * (regnum - TIC6X_B4_REGNUM + 3);        /* B4, B6, B8 */
  62.   else if (regnum == TIC6X_B5_REGNUM || regnum == TIC6X_B5_REGNUM + 2
  63.            || regnum == TIC6X_B5_REGNUM + 4)
  64.     return 4 * (regnum - TIC6X_B5_REGNUM + 19);        /* B5, B7, B9 */
  65.   else if (regnum < TIC6X_A4_REGNUM)
  66.     return 4 * (regnum - 0 + 8);        /* A0 - A3 */
  67.   else if (regnum >= TIC6X_B0_REGNUM && regnum < TIC6X_B4_REGNUM)
  68.     return 4 * (regnum - TIC6X_B0_REGNUM + 15);        /* B0 - B3 */
  69.   else if (regnum >= 34 && regnum < 34 + 32)
  70.     return 4 * (regnum - 34 + 23);        /* A16 - A31, B16 - B31 */
  71.   else if (regnum == TIC6X_PC_REGNUM)
  72.     return 4 * (tdep->has_gp ? 55 : 23);
  73.   else if (regnum == TIC6X_SP_REGNUM)
  74.     return 4;

  76.   return 0;
  77. }

  79. /* Support unwinding frame in signal trampoline.  We don't check sigreturn,
  80.    since it is not used in kernel.  */

  82. static void
  83. ‌tic6x_linux_rt_sigreturn_init (const struct tramp_frame *self,
  84.                                struct frame_info *this_frame,
  85.                                struct trad_frame_cache *this_cache,
  86.                                CORE_ADDR func)
  87. {
  88.   struct gdbarch *gdbarch = get_frame_arch (this_frame);
  89.   CORE_ADDR sp = get_frame_register_unsigned (this_frame, TIC6X_SP_REGNUM);
  90.   /* The base of struct sigcontext is computed by examining the definition of
  91.      struct rt_sigframe in linux kernel source arch/c6x/kernel/signal.c.  */
  92.   CORE_ADDR base = (sp + TIC6X_SP_RT_SIGFRAME
  93.                     /* Pointer type *pinfo and *puc in struct rt_sigframe.  */
  94.                     + 4 + 4
  95.                     + TIC6X_SIGINFO_SIZE
  96.                     + 4 + 4 /* uc_flags and *uc_link in struct ucontext.  */
  97.                     + TIC6X_STACK_T_SIZE);
  98.   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  99.   unsigned int reg_offset;
  100.   unsigned int i;

  102.   for (i = 0; i < 10; i++)        /* A0 - A9 */
  103.     {
  104.       reg_offset = tic6x_register_sigcontext_offset (i, gdbarch);
  105.       gdb_assert (reg_offset != 0);

  107.       trad_frame_set_reg_addr (this_cache, i, base + reg_offset);
  108.     }

  110.   for (i = TIC6X_B0_REGNUM; i < TIC6X_B0_REGNUM + 10; i++)        /* B0 - B9 */
  111.     {
  112.       reg_offset = tic6x_register_sigcontext_offset (i, gdbarch);
  113.       gdb_assert (reg_offset != 0);

  115.       trad_frame_set_reg_addr (this_cache, i, base + reg_offset);
  116.     }

  118.   if (tdep->has_gp)
  119.     for (i = 34; i < 34 + 32; i++)        /* A16 - A31, B16 - B31 */
  120.       {
  121.         reg_offset = tic6x_register_sigcontext_offset (i, gdbarch);
  122.         gdb_assert (reg_offset != 0);

  124.         trad_frame_set_reg_addr (this_cache, i, base + reg_offset);
  125.       }

  127.   trad_frame_set_reg_addr (this_cache, TIC6X_PC_REGNUM,
  128.                            base + tic6x_register_sigcontext_offset (TIC6X_PC_REGNUM,
  129.                                                                     gdbarch));
  130.   trad_frame_set_reg_addr (this_cache, TIC6X_SP_REGNUM,
  131.                            base + tic6x_register_sigcontext_offset (TIC6X_SP_REGNUM,
  132.                                                                     gdbarch));

  134.   /* Save a frame ID.  */
  135.   trad_frame_set_id (this_cache, frame_id_build (sp, func));
  136. }

  138. ‌static struct tramp_frame tic6x_linux_rt_sigreturn_tramp_frame =
  139. {
  140.   SIGTRAMP_FRAME,
  141.   4,
  142.   {
  143.     {0x000045aa, 0x0fffffff},        /* mvk .S2 139,b0 */
  144.     {0x10000000, -1},                /* swe */
  145.     {TRAMP_SENTINEL_INSN}
  146.   },
  147.   tic6x_linux_rt_sigreturn_init
  148. };

  150. /* When FRAME is at a syscall instruction, return the PC of the next
  151.    instruction to be executed.  */

  153. static CORE_ADDR
  154. ‌tic6x_linux_syscall_next_pc (struct frame_info *frame)
  155. {
  156.   ULONGEST syscall_number = get_frame_register_unsigned (frame,
  157.                                                          TIC6X_B0_REGNUM);
  158.   CORE_ADDR pc = get_frame_pc (frame);

  160.   if (syscall_number == 139 /* rt_sigreturn */)
  161.     return frame_unwind_caller_pc (frame);

  163.   return pc + 4;
  164. }


  167. extern struct target_so_ops dsbt_so_ops;
  168. static void
  169. ‌tic6x_uclinux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
  170. {
  171.   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  173.   linux_init_abi (info, gdbarch);

  175.   /* Shared library handling.  */
  176.   set_solib_ops (gdbarch, &dsbt_so_ops);

  178.   tdep->syscall_next_pc = tic6x_linux_syscall_next_pc;

  180. #ifdef HAVE_ELF
  181.   /* In tic6x Linux kernel, breakpoint instructions varies on different archs.
  182.      On C64x+ and C67x+, breakpoint instruction is 0x56454314, which is an
  183.      illegal opcode.  On other arch, breakpoint instruction is 0x0000a122
  184.      (BNOP .S2 0,5).  */
  185.   if (info.abfd)
  186.     switch (bfd_elf_get_obj_attr_int (info.abfd, OBJ_ATTR_PROC, Tag_ISA))
  187.       {
  188.       case C6XABI_Tag_ISA_C64XP:
  189.       case C6XABI_Tag_ISA_C67XP:
  190.         if (info.byte_order == BFD_ENDIAN_BIG)
  191.           tdep->breakpoint = tic6x_bkpt_illegal_opcode_be;
  192.         else
  193.           tdep->breakpoint = tic6x_bkpt_illegal_opcode_le;
  194.         break;
  195.       default:
  196.         {
  197.           if (info.byte_order == BFD_ENDIAN_BIG)
  198.             tdep->breakpoint = tic6x_bkpt_bnop_be;
  199.           else
  200.             tdep->breakpoint = tic6x_bkpt_bnop_le;
  201.         }
  202.       }
  203. #endif

  205.   /* Signal trampoline support.  */
  206.   tramp_frame_prepend_unwinder (gdbarch,
  207.                                 &tic6x_linux_rt_sigreturn_tramp_frame);
  208. }

  210. /* Provide a prototype to silence -Wmissing-prototypes.  */
  211. extern initialize_file_ftype _initialize_tic6x_linux_tdep;

  213. void
  214. ‌_initialize_tic6x_linux_tdep (void)
  215. {
  216.   gdbarch_register_osabi (bfd_arch_tic6x, 0, GDB_OSABI_LINUX,
  217.                           tic6x_uclinux_init_abi);

  219.   initialize_tdesc_tic6x_c64xp_linux ();
  220.   initialize_tdesc_tic6x_c64x_linux ();
  221.   initialize_tdesc_tic6x_c62x_linux ();
  222. }