| 1 | /* Dwarf2 Expression Evaluator |
| 2 | Copyright 2001, 2002, 2003 Free Software Foundation, Inc. |
| 3 | Contributed by Daniel Berlin (dan@dberlin.org) |
| 4 | This file is part of GDB. |
| 5 | |
| 6 | This program is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 19 | Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | #if !defined (DWARF2EXPR_H) |
| 22 | #define DWARF2EXPR_H |
| 23 | |
| 24 | /* The expression evaluator works with a dwarf_expr_context, describing |
| 25 | its current state and its callbacks. */ |
| 26 | struct dwarf_expr_context |
| 27 | { |
| 28 | /* The stack of values, allocated with xmalloc. */ |
| 29 | CORE_ADDR *stack; |
| 30 | |
| 31 | /* The number of values currently pushed on the stack, and the |
| 32 | number of elements allocated to the stack. */ |
| 33 | int stack_len, stack_allocated; |
| 34 | |
| 35 | /* An opaque argument provided by the caller, which will be passed |
| 36 | to all of the callback functions. */ |
| 37 | void *baton; |
| 38 | |
| 39 | /* Return the value of register number REGNUM. */ |
| 40 | CORE_ADDR (*read_reg) (void *baton, int regnum); |
| 41 | |
| 42 | /* Read LENGTH bytes at ADDR into BUF. */ |
| 43 | void (*read_mem) (void *baton, char *buf, CORE_ADDR addr, |
| 44 | size_t length); |
| 45 | |
| 46 | /* Return the location expression for the frame base attribute, in |
| 47 | START and LENGTH. The result must be live until the current |
| 48 | expression evaluation is complete. */ |
| 49 | void (*get_frame_base) (void *baton, unsigned char **start, |
| 50 | size_t *length); |
| 51 | |
| 52 | /* Return the thread-local storage address for |
| 53 | DW_OP_GNU_push_tls_address. */ |
| 54 | CORE_ADDR (*get_tls_address) (void *baton, CORE_ADDR offset); |
| 55 | |
| 56 | #if 0 |
| 57 | /* Not yet implemented. */ |
| 58 | |
| 59 | /* Return the location expression for the dwarf expression |
| 60 | subroutine in the die at OFFSET in the current compilation unit. |
| 61 | The result must be live until the current expression evaluation |
| 62 | is complete. */ |
| 63 | unsigned char *(*get_subr) (void *baton, off_t offset, size_t *length); |
| 64 | |
| 65 | /* Return the `object address' for DW_OP_push_object_address. */ |
| 66 | CORE_ADDR (*get_object_address) (void *baton); |
| 67 | #endif |
| 68 | |
| 69 | /* The current depth of dwarf expression recursion, via DW_OP_call*, |
| 70 | DW_OP_fbreg, DW_OP_push_object_address, etc., and the maximum |
| 71 | depth we'll tolerate before raising an error. */ |
| 72 | int recursion_depth, max_recursion_depth; |
| 73 | |
| 74 | /* Non-zero if the result is in a register. The register number |
| 75 | will be on the expression stack. */ |
| 76 | int in_reg; |
| 77 | }; |
| 78 | |
| 79 | struct dwarf_expr_context *new_dwarf_expr_context (); |
| 80 | void free_dwarf_expr_context (struct dwarf_expr_context *ctx); |
| 81 | |
| 82 | void dwarf_expr_push (struct dwarf_expr_context *ctx, CORE_ADDR value); |
| 83 | void dwarf_expr_pop (struct dwarf_expr_context *ctx); |
| 84 | void dwarf_expr_eval (struct dwarf_expr_context *ctx, unsigned char *addr, |
| 85 | size_t len); |
| 86 | CORE_ADDR dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n); |
| 87 | |
| 88 | |
| 89 | unsigned char *read_uleb128 (unsigned char *buf, unsigned char *buf_end, |
| 90 | ULONGEST * r); |
| 91 | unsigned char *read_sleb128 (unsigned char *buf, unsigned char *buf_end, |
| 92 | LONGEST * r); |
| 93 | CORE_ADDR dwarf2_read_address (unsigned char *buf, unsigned char *buf_end, |
| 94 | int *bytes_read); |
| 95 | |
| 96 | #endif |