1 /* DWARF 2 location expression support for GDB. 2 3 Copyright (C) 2003, 2005, 2007, 2008, 2009, 2010, 2011 4 Free Software Foundation, Inc. 5 6 This file is part of GDB. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 3 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 20 21 #if !defined (DWARF2LOC_H) 22 #define DWARF2LOC_H 23 24 struct symbol_computed_ops; 25 struct objfile; 26 struct dwarf2_per_cu_data; 27 struct dwarf2_loclist_baton; 28 struct agent_expr; 29 struct axs_value; 30 31 /* This header is private to the DWARF-2 reader. It is shared between 32 dwarf2read.c and dwarf2loc.c. */ 33 34 /* Return the OBJFILE associated with the compilation unit CU. If CU 35 came from a separate debuginfo file, then the master objfile is 36 returned. */ 37 struct objfile *dwarf2_per_cu_objfile (struct dwarf2_per_cu_data *cu); 38 39 /* Return the address size given in the compilation unit header for CU. */ 40 CORE_ADDR dwarf2_per_cu_addr_size (struct dwarf2_per_cu_data *cu); 41 42 /* Return the offset size given in the compilation unit header for CU. */ 43 int dwarf2_per_cu_offset_size (struct dwarf2_per_cu_data *cu); 44 45 /* Return the text offset of the CU. The returned offset comes from 46 this CU's objfile. If this objfile came from a separate debuginfo 47 file, then the offset may be different from the corresponding 48 offset in the parent objfile. */ 49 CORE_ADDR dwarf2_per_cu_text_offset (struct dwarf2_per_cu_data *cu); 50 51 /* Find a particular location expression from a location list. */ 52 const gdb_byte *dwarf2_find_location_expression 53 (struct dwarf2_loclist_baton *baton, 54 size_t *locexpr_length, 55 CORE_ADDR pc); 56 57 struct dwarf2_locexpr_baton dwarf2_fetch_die_location_block 58 (unsigned int offset, struct dwarf2_per_cu_data *per_cu, 59 CORE_ADDR (*get_frame_pc) (void *baton), 60 void *baton); 61 62 /* Evaluate a location description, starting at DATA and with length 63 SIZE, to find the current location of variable of TYPE in the context 64 of FRAME. */ 65 66 struct value *dwarf2_evaluate_loc_desc (struct type *type, 67 struct frame_info *frame, 68 const gdb_byte *data, 69 unsigned short size, 70 struct dwarf2_per_cu_data *per_cu); 71 72 /* The symbol location baton types used by the DWARF-2 reader (i.e. 73 SYMBOL_LOCATION_BATON for a LOC_COMPUTED symbol). "struct 74 dwarf2_locexpr_baton" is for a symbol with a single location 75 expression; "struct dwarf2_loclist_baton" is for a symbol with a 76 location list. */ 77 78 struct dwarf2_locexpr_baton 79 { 80 /* Pointer to the start of the location expression. */ 81 const gdb_byte *data; 82 83 /* Length of the location expression. */ 84 unsigned long size; 85 86 /* The compilation unit containing the symbol whose location 87 we're computing. */ 88 struct dwarf2_per_cu_data *per_cu; 89 }; 90 91 struct dwarf2_loclist_baton 92 { 93 /* The initial base address for the location list, based on the compilation 94 unit. */ 95 CORE_ADDR base_address; 96 97 /* Pointer to the start of the location list. */ 98 const gdb_byte *data; 99 100 /* Length of the location list. */ 101 unsigned long size; 102 103 /* The compilation unit containing the symbol whose location 104 we're computing. */ 105 struct dwarf2_per_cu_data *per_cu; 106 }; 107 108 extern const struct symbol_computed_ops dwarf2_locexpr_funcs; 109 extern const struct symbol_computed_ops dwarf2_loclist_funcs; 110 111 /* Compile a DWARF location expression to an agent expression. 112 113 EXPR is the agent expression we are building. 114 LOC is the agent value we modify. 115 ARCH is the architecture. 116 ADDR_SIZE is the size of addresses, in bytes. 117 OP_PTR is the start of the location expression. 118 OP_END is one past the last byte of the location expression. 119 120 This will throw an exception for various kinds of errors -- for 121 example, if the expression cannot be compiled, or if the expression 122 is invalid. */ 123 124 extern void dwarf2_compile_expr_to_ax (struct agent_expr *expr, 125 struct axs_value *loc, 126 struct gdbarch *arch, 127 unsigned int addr_size, 128 const gdb_byte *op_ptr, 129 const gdb_byte *op_end, 130 struct dwarf2_per_cu_data *per_cu); 131 132 #endif /* dwarf2loc.h */ 133