1 /* Frame unwinder for frames with DWARF Call Frame Information. 2 3 Copyright (C) 2003-2013 Free Software Foundation, Inc. 4 5 Contributed by Mark Kettenis. 6 7 This file is part of GDB. 8 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. 13 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. 18 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/>. */ 21 22 #ifndef DWARF2_FRAME_H 23 #define DWARF2_FRAME_H 1 24 25 struct gdbarch; 26 struct objfile; 27 struct frame_info; 28 struct dwarf2_per_cu_data; 29 struct agent_expr; 30 struct axs_value; 31 32 /* Register rule. */ 33 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, 42 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, 54 55 /* These are defined in Dwarf3. */ 56 DWARF2_FRAME_REG_SAVED_VAL_OFFSET, 57 DWARF2_FRAME_REG_SAVED_VAL_EXP, 58 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 }; 67 68 /* Register state. */ 69 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 }; 84 85 /* Set the architecture-specific register state initialization 86 function for GDBARCH to INIT_REG. */ 87 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 *)); 92 93 /* Set the architecture-specific signal trampoline recognition 94 function for GDBARCH to SIGNAL_FRAME_P. */ 95 96 extern void 97 dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, 98 int (*signal_frame_p) (struct gdbarch *, 99 struct frame_info *)); 100 101 /* Set the architecture-specific adjustment of .eh_frame and .debug_frame 102 register numbers. */ 103 104 extern void 105 dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, 106 int (*adjust_regnum) (struct gdbarch *, 107 int, int)); 108 109 /* Append the DWARF-2 frame unwinders to GDBARCH's list. */ 110 111 void dwarf2_append_unwinders (struct gdbarch *gdbarch); 112 113 /* 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. */ 115 116 extern const struct frame_base * 117 dwarf2_frame_base_sniffer (struct frame_info *this_frame); 118 119 /* Compute the DWARF CFA for a frame. */ 120 121 CORE_ADDR dwarf2_frame_cfa (struct frame_info *this_frame); 122 123 /* Update the agent expression EXPR with code to compute the CFA for a 124 frame at PC. GDBARCH is the architecture of the function at PC. 125 This function may call dwarf2_compile_expr_to_ax; DATA is passed 126 through to that function if needed. */ 127 128 extern void dwarf2_compile_cfa_to_ax (struct agent_expr *expr, 129 struct axs_value *loc, 130 struct gdbarch *gdbarch, 131 CORE_ADDR pc, 132 struct dwarf2_per_cu_data *data); 133 134 #endif /* dwarf2-frame.h */ 135