gdb/dwarf2-frame.h - gdb

Data types defined

Macros defined

Source code

  1. /* Frame unwinder for frames with DWARF Call Frame Information.

  3.    Copyright (C) 2003-2015 Free Software Foundation, Inc.

  5.    Contributed by Mark Kettenis.

  7.    This file is part of GDB.

  9.    This program is free software; you can redistribute it and/or modify
  10.    it under the terms of the GNU General Public License as published by
  11.    the Free Software Foundation; either version 3 of the License, or
  12.    (at your option) any later version.

  14.    This program is distributed in the hope that it will be useful,
  15.    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16.    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17.    GNU General Public License for more details.

  19.    You should have received a copy of the GNU General Public License
  20.    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

  22. #ifndef DWARF2_FRAME_H
  23. ‌#define DWARF2_FRAME_H 1

  25. struct gdbarch;
  26. struct objfile;
  27. struct frame_info;
  28. struct dwarf2_per_cu_data;
  29. struct agent_expr;
  30. struct axs_value;

  32. /* Register rule.  */

  34. ‌enum dwarf2_frame_reg_rule
  35. {
  36.   /* Make certain that 0 maps onto the correct enum value; the
  37.      corresponding structure is being initialized using memset zero.
  38.      This indicates that CFI didn't provide any information at all
  39.      about a register, leaving how to obtain its value totally
  40.      unspecified.  */
  41.   DWARF2_FRAME_REG_UNSPECIFIED = 0,

  43.   /* The term "undefined" comes from the DWARF2 CFI spec which this
  44.      code is moddeling; it indicates that the register's value is
  45.      "undefined".  GCC uses the less formal term "unsaved".  Its
  46.      definition is a combination of REG_UNDEFINED and REG_UNSPECIFIED.
  47.      The failure to differentiate the two helps explain a few problems
  48.      with the CFI generated by GCC.  */
  49.   DWARF2_FRAME_REG_UNDEFINED,
  50.   DWARF2_FRAME_REG_SAVED_OFFSET,
  51.   DWARF2_FRAME_REG_SAVED_REG,
  52.   DWARF2_FRAME_REG_SAVED_EXP,
  53.   DWARF2_FRAME_REG_SAME_VALUE,

  55.   /* These are defined in Dwarf3.  */
  56.   DWARF2_FRAME_REG_SAVED_VAL_OFFSET,
  57.   DWARF2_FRAME_REG_SAVED_VAL_EXP,

  59.   /* These aren't defined by the DWARF2 CFI specification, but are
  60.      used internally by GDB.  */
  61.   DWARF2_FRAME_REG_FN,                /* Call a registered function.  */
  62.   DWARF2_FRAME_REG_RA,                /* Return Address.  */
  63.   DWARF2_FRAME_REG_RA_OFFSET,        /* Return Address with offset.  */
  64.   DWARF2_FRAME_REG_CFA,                /* Call Frame Address.  */
  65.   DWARF2_FRAME_REG_CFA_OFFSET        /* Call Frame Address with offset.  */
  66. };

  68. /* Register state.  */

  70. ‌struct dwarf2_frame_state_reg
  71. {
  72.   /* Each register save state can be described in terms of a CFA slot,
  73.      another register, or a location expression.  */
  74.   union {
  75.     LONGEST offset;
  76.     ULONGEST reg;
  77.     const gdb_byte *exp;
  78.     struct value *(*fn) (struct frame_info *this_frame, void **this_cache,
  79.                          int regnum);
  80.   } loc;
  81.   ULONGEST exp_len;
  82.   enum dwarf2_frame_reg_rule how;
  83. };

  85. /* Set the architecture-specific register state initialization
  86.    function for GDBARCH to INIT_REG.  */

  88. extern void dwarf2_frame_set_init_reg (struct gdbarch *gdbarch,
  89.                                        void (*init_reg) (struct gdbarch *, int,
  90.                                              struct dwarf2_frame_state_reg *,
  91.                                              struct frame_info *));

  93. /* Set the architecture-specific signal trampoline recognition
  94.    function for GDBARCH to SIGNAL_FRAME_P.  */

  96. extern void
  97.   dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch,
  98.                                    int (*signal_frame_p) (struct gdbarch *,
  99.                                                           struct frame_info *));

  101. /* Set the architecture-specific adjustment of .eh_frame and .debug_frame
  102.    register numbers.  */

  104. extern void
  105.   dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch,
  106.                                   int (*adjust_regnum) (struct gdbarch *,
  107.                                                         int, int));

  109. /* Append the DWARF-2 frame unwinders to GDBARCH's list.  */

  111. void dwarf2_append_unwinders (struct gdbarch *gdbarch);

  113. /* Return the frame base methods for the function that contains PC, or
  114.    NULL if it can't be handled by the DWARF CFI frame unwinder.  */

  116. extern const struct frame_base *
  117.   dwarf2_frame_base_sniffer (struct frame_info *this_frame);

  119. /* Compute the DWARF CFA for a frame.  */

  121. CORE_ADDR dwarf2_frame_cfa (struct frame_info *this_frame);

  123. /* Find the CFA information for PC.

  125.    Return 1 if a register is used for the CFA, or 0 if another
  126.    expression is used.  Throw an exception on error.

  128.    GDBARCH is the architecture to use.
  129.    DATA is the per-CU data.

  131.    REGNUM_OUT is an out parameter that is set to the register number.
  132.    OFFSET_OUT is the offset to use from this register.
  133.    These are only filled in when 1 is returned.

  135.    TEXT_OFFSET_OUT, CFA_START_OUT, and CFA_END_OUT describe the CFA
  136.    in other cases.  These are only used when 0 is returned.  */

  138. extern int dwarf2_fetch_cfa_info (struct gdbarch *gdbarch, CORE_ADDR pc,
  139.                                   struct dwarf2_per_cu_data *data,
  140.                                   int *regnum_out, LONGEST *offset_out,
  141.                                   CORE_ADDR *text_offset_out,
  142.                                   const gdb_byte **cfa_start_out,
  143.                                   const gdb_byte **cfa_end_out);

  145. #endif /* dwarf2-frame.h */