1/* Code dealing with register stack frames, for GDB, the GNU debugger. 2 3 Copyright (C) 1986-2020 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 3 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, see <http://www.gnu.org/licenses/>. */ 19 20 21#include "defs.h" 22#include "regcache.h" 23#include "sentinel-frame.h" 24#include "inferior.h" 25#include "frame-unwind.h" 26 27struct frame_unwind_cache 28{ 29 struct regcache *regcache; 30}; 31 32void * 33sentinel_frame_cache (struct regcache *regcache) 34{ 35 struct frame_unwind_cache *cache = 36 FRAME_OBSTACK_ZALLOC (struct frame_unwind_cache); 37 38 cache->regcache = regcache; 39 return cache; 40} 41 42/* Here the register value is taken direct from the register cache. */ 43 44static struct value * 45sentinel_frame_prev_register (struct frame_info *this_frame, 46 void **this_prologue_cache, 47 int regnum) 48{ 49 struct frame_unwind_cache *cache 50 = (struct frame_unwind_cache *) *this_prologue_cache; 51 struct value *value; 52 53 value = cache->regcache->cooked_read_value (regnum); 54 VALUE_NEXT_FRAME_ID (value) = sentinel_frame_id; 55 56 return value; 57} 58 59static void 60sentinel_frame_this_id (struct frame_info *this_frame, 61 void **this_prologue_cache, 62 struct frame_id *this_id) 63{ 64 /* The sentinel frame is used as a starting point for creating the 65 previous (inner most) frame. That frame's THIS_ID method will be 66 called to determine the inner most frame's ID. Not this one. */ 67 internal_error (__FILE__, __LINE__, _("sentinel_frame_this_id called")); 68} 69 70static struct gdbarch * 71sentinel_frame_prev_arch (struct frame_info *this_frame, 72 void **this_prologue_cache) 73{ 74 struct frame_unwind_cache *cache 75 = (struct frame_unwind_cache *) *this_prologue_cache; 76 77 return cache->regcache->arch (); 78} 79 80const struct frame_unwind sentinel_frame_unwind = 81{ 82 SENTINEL_FRAME, 83 default_frame_unwind_stop_reason, 84 sentinel_frame_this_id, 85 sentinel_frame_prev_register, 86 NULL, 87 NULL, 88 NULL, 89 sentinel_frame_prev_arch, 90}; 91