1 /* Signal trampoline unwinder, for GDB the GNU Debugger. 2 3 Copyright 2004 Free Software Foundation, Inc. 4 5 This file is part of GDB. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 2 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 59 Temple Place - Suite 330, 20 Boston, MA 02111-1307, USA. */ 21 22 #ifndef TRAMP_FRAME_H 23 #define TRAMP_FRAME_H 24 25 #include "frame.h" /* For "enum frame_type". */ 26 27 struct trad_frame; 28 struct frame_info; 29 struct trad_frame_cache; 30 31 /* A trampoline consists of a small sequence of instructions placed at 32 an unspecified location in the inferior's address space. The only 33 identifying attribute of the trampoline's address is that it does 34 not fall inside an object file's section. 35 36 The only way to identify a trampoline is to perform a brute force 37 examination of the instructions at and around the PC. 38 39 This module provides a convent interface for performing that 40 operation. */ 41 42 /* A trampoline descriptor. */ 43 44 /* Magic instruction that to mark the end of the signal trampoline 45 instruction sequence. */ 46 #define TRAMP_SENTINEL_INSN ((LONGEST) -1) 47 48 struct tramp_frame 49 { 50 /* The trampoline's type, some a signal trampolines, some are normal 51 call-frame trampolines (aka thunks). */ 52 enum frame_type frame_type; 53 /* The trampoline's entire instruction sequence. It consists of a 54 bytes/mask pair. Search for this in the inferior at or around 55 the frame's PC. It is assumed that the PC is INSN_SIZE aligned, 56 and that each element of TRAMP contains one INSN_SIZE 57 instruction. It is also assumed that INSN[0] contains the first 58 instruction of the trampoline and hence the address of the 59 instruction matching INSN[0] is the trampoline's "func" address. 60 The instruction sequence is terminated by 61 TRAMP_SENTINEL_INSN. */ 62 int insn_size; 63 struct 64 { 65 ULONGEST bytes; 66 ULONGEST mask; 67 } insn[8]; 68 /* Initialize a trad-frame cache corresponding to the tramp-frame. 69 FUNC is the address of the instruction TRAMP[0] in memory. */ 70 void (*init) (const struct tramp_frame *self, 71 struct frame_info *next_frame, 72 struct trad_frame_cache *this_cache, 73 CORE_ADDR func); 74 }; 75 76 void tramp_frame_prepend_unwinder (struct gdbarch *gdbarch, 77 const struct tramp_frame *tramp); 78 79 #endif 80