1 /* Frame unwinder for frames with DWARF Call Frame Information. 2 3 Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011 4 Free Software Foundation, Inc. 5 6 Contributed by Mark Kettenis. 7 8 This file is part of GDB. 9 10 This program is free software; you can redistribute it and/or modify 11 it under the terms of the GNU General Public License as published by 12 the Free Software Foundation; either version 3 of the License, or 13 (at your option) any later version. 14 15 This program is distributed in the hope that it will be useful, 16 but WITHOUT ANY WARRANTY; without even the implied warranty of 17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 GNU General Public License for more details. 19 20 You should have received a copy of the GNU General Public License 21 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 22 23 #ifndef DWARF2_FRAME_H 24 #define DWARF2_FRAME_H 1 25 26 struct gdbarch; 27 struct objfile; 28 struct frame_info; 29 struct dwarf2_per_cu_data; 30 struct agent_expr; 31 struct axs_value; 32 33 /* Register rule. */ 34 35 enum dwarf2_frame_reg_rule 36 { 37 /* Make certain that 0 maps onto the correct enum value; the 38 corresponding structure is being initialized using memset zero. 39 This indicates that CFI didn't provide any information at all 40 about a register, leaving how to obtain its value totally 41 unspecified. */ 42 DWARF2_FRAME_REG_UNSPECIFIED = 0, 43 44 /* The term "undefined" comes from the DWARF2 CFI spec which this 45 code is moddeling; it indicates that the register's value is 46 "undefined". GCC uses the less formal term "unsaved". Its 47 definition is a combination of REG_UNDEFINED and REG_UNSPECIFIED. 48 The failure to differentiate the two helps explain a few problems 49 with the CFI generated by GCC. */ 50 DWARF2_FRAME_REG_UNDEFINED, 51 DWARF2_FRAME_REG_SAVED_OFFSET, 52 DWARF2_FRAME_REG_SAVED_REG, 53 DWARF2_FRAME_REG_SAVED_EXP, 54 DWARF2_FRAME_REG_SAME_VALUE, 55 56 /* These are defined in Dwarf3. */ 57 DWARF2_FRAME_REG_SAVED_VAL_OFFSET, 58 DWARF2_FRAME_REG_SAVED_VAL_EXP, 59 60 /* These aren't defined by the DWARF2 CFI specification, but are 61 used internally by GDB. */ 62 DWARF2_FRAME_REG_FN, /* Call a registered function. */ 63 DWARF2_FRAME_REG_RA, /* Return Address. */ 64 DWARF2_FRAME_REG_RA_OFFSET, /* Return Address with offset. */ 65 DWARF2_FRAME_REG_CFA, /* Call Frame Address. */ 66 DWARF2_FRAME_REG_CFA_OFFSET /* Call Frame Address with offset. */ 67 }; 68 69 /* Register state. */ 70 71 struct dwarf2_frame_state_reg 72 { 73 /* Each register save state can be described in terms of a CFA slot, 74 another register, or a location expression. */ 75 union { 76 LONGEST offset; 77 ULONGEST reg; 78 const gdb_byte *exp; 79 struct value *(*fn) (struct frame_info *this_frame, void **this_cache, 80 int regnum); 81 } loc; 82 ULONGEST exp_len; 83 enum dwarf2_frame_reg_rule how; 84 }; 85 86 /* Set the architecture-specific register state initialization 87 function for GDBARCH to INIT_REG. */ 88 89 extern void dwarf2_frame_set_init_reg (struct gdbarch *gdbarch, 90 void (*init_reg) (struct gdbarch *, int, 91 struct dwarf2_frame_state_reg *, 92 struct frame_info *)); 93 94 /* Set the architecture-specific signal trampoline recognition 95 function for GDBARCH to SIGNAL_FRAME_P. */ 96 97 extern void 98 dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, 99 int (*signal_frame_p) (struct gdbarch *, 100 struct frame_info *)); 101 102 /* Set the architecture-specific adjustment of .eh_frame and .debug_frame 103 register numbers. */ 104 105 extern void 106 dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, 107 int (*adjust_regnum) (struct gdbarch *, 108 int, int)); 109 110 /* Append the DWARF-2 frame unwinders to GDBARCH's list. */ 111 112 void dwarf2_append_unwinders (struct gdbarch *gdbarch); 113 114 /* Return the frame base methods for the function that contains PC, or 115 NULL if it can't be handled by the DWARF CFI frame unwinder. */ 116 117 extern const struct frame_base * 118 dwarf2_frame_base_sniffer (struct frame_info *this_frame); 119 120 /* Compute the DWARF CFA for a frame. */ 121 122 CORE_ADDR dwarf2_frame_cfa (struct frame_info *this_frame); 123 124 /* Update the agent expression EXPR with code to compute the CFA for a 125 frame at PC. GDBARCH is the architecture of the function at PC. 126 This function may call dwarf2_compile_expr_to_ax; DATA is passed 127 through to that function if needed. */ 128 129 extern void dwarf2_compile_cfa_to_ax (struct agent_expr *expr, 130 struct axs_value *loc, 131 struct gdbarch *gdbarch, 132 CORE_ADDR pc, 133 struct dwarf2_per_cu_data *data); 134 135 #endif /* dwarf2-frame.h */ 136