/* Signal trampoline unwinder. Copyright (C) 2004-2019 Free Software Foundation, Inc. This file is part of GDB. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ #ifndef TRAMP_FRAME_H #define TRAMP_FRAME_H #include "frame.h" /* For "enum frame_type". */ struct trad_frame; struct frame_info; struct trad_frame_cache; /* A trampoline consists of a small sequence of instructions placed at an unspecified location in the inferior's address space. The only identifying attribute of the trampoline's address is that it does not fall inside an object file's section. The only way to identify a trampoline is to perform a brute force examination of the instructions at and around the PC. This module provides a convenient interface for performing that operation. */ /* A trampoline descriptor. */ /* Magic instruction that to mark the end of the signal trampoline instruction sequence. */ #define TRAMP_SENTINEL_INSN ULONGEST_MAX struct tramp_frame { /* The trampoline's type, some a signal trampolines, some are normal call-frame trampolines (aka thunks). */ enum frame_type frame_type; /* The trampoline's entire instruction sequence. It consists of a bytes/mask pair. Search for this in the inferior at or around the frame's PC. It is assumed that the PC is INSN_SIZE aligned, and that each element of TRAMP contains one INSN_SIZE instruction. It is also assumed that INSN[0] contains the first instruction of the trampoline and hence the address of the instruction matching INSN[0] is the trampoline's "func" address. The instruction sequence is terminated by TRAMP_SENTINEL_INSN. */ int insn_size; struct { ULONGEST bytes; ULONGEST mask; } insn[48]; /* Initialize a trad-frame cache corresponding to the tramp-frame. FUNC is the address of the instruction TRAMP[0] in memory. */ void (*init) (const struct tramp_frame *self, struct frame_info *this_frame, struct trad_frame_cache *this_cache, CORE_ADDR func); /* Return non-zero if the tramp-frame is valid for the PC requested. Adjust the PC to point to the address to check the instruction sequence against if required. If this is NULL, then the tramp-frame is valid for any PC. */ int (*validate) (const struct tramp_frame *self, struct frame_info *this_frame, CORE_ADDR *pc); }; void tramp_frame_prepend_unwinder (struct gdbarch *gdbarch, const struct tramp_frame *tramp); #endif