gdb/frame-base.c

   1 /* Definitions for frame address handler, for GDB, the GNU debugger.
   2
   3    Copyright (C) 2003-2022 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 #include "defs.h"
  21 #include "frame-base.h"
  22 #include "frame.h"
  23 #include "gdbsupport/gdb_obstack.h"
  24 #include "gdbarch.h"
  25
  26 /* A default frame base implementations.  If it wasn't for the old
  27    DEPRECATED_FRAME_LOCALS_ADDRESS and DEPRECATED_FRAME_ARGS_ADDRESS,
  28    these could be combined into a single function.  All architectures
  29    really need to override this.  */
  30
  31 static CORE_ADDR
  32 default_frame_base_address (struct frame_info *this_frame, void **this_cache)
  33 {
  34   return get_frame_base (this_frame); /* sigh! */
  35 }
  36
  37 static CORE_ADDR
  38 default_frame_locals_address (struct frame_info *this_frame, void **this_cache)
  39 {
  40   return default_frame_base_address (this_frame, this_cache);
  41 }
  42
  43 static CORE_ADDR
  44 default_frame_args_address (struct frame_info *this_frame, void **this_cache)
  45 {
  46   return default_frame_base_address (this_frame, this_cache);
  47 }
  48
  49 const struct frame_base default_frame_base = {
  50   NULL, /* No parent.  */
  51   default_frame_base_address,
  52   default_frame_locals_address,
  53   default_frame_args_address
  54 };
  55
  56 struct frame_base_table_entry
  57 {
  58   frame_base_sniffer_ftype *sniffer;
  59   struct frame_base_table_entry *next;
  60 };
  61
  62 struct frame_base_table
  63 {
  64   struct frame_base_table_entry *head = nullptr;
  65   struct frame_base_table_entry **tail = &head;
  66   const struct frame_base *default_base = &default_frame_base;
  67 };
  68
  69 static const registry<gdbarch>::key<struct frame_base_table> frame_base_data;
  70
  71 static struct frame_base_table *
  72 get_frame_base_table (struct gdbarch *gdbarch)
  73 {
  74   struct frame_base_table *table = frame_base_data.get (gdbarch);
  75   if (table == nullptr)
  76     table = frame_base_data.emplace (gdbarch);
  77   return table;
  78 }
  79
  80 void
  81 frame_base_append_sniffer (struct gdbarch *gdbarch,
  82                            frame_base_sniffer_ftype *sniffer)
  83 {
  84   struct frame_base_table *table = get_frame_base_table (gdbarch);
  85
  86   (*table->tail)
  87     = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_base_table_entry);
  88   (*table->tail)->sniffer = sniffer;
  89   table->tail = &(*table->tail)->next;
  90 }
  91
  92 void
  93 frame_base_set_default (struct gdbarch *gdbarch,
  94                         const struct frame_base *default_base)
  95 {
  96   struct frame_base_table *table = get_frame_base_table (gdbarch);
  97
  98   table->default_base = default_base;
  99 }
 100
 101 const struct frame_base *
 102 frame_base_find_by_frame (struct frame_info *this_frame)
 103 {
 104   struct gdbarch *gdbarch = get_frame_arch (this_frame);
 105   struct frame_base_table *table = get_frame_base_table (gdbarch);
 106   struct frame_base_table_entry *entry;
 107
 108   for (entry = table->head; entry != NULL; entry = entry->next)
 109     {
 110       const struct frame_base *desc = NULL;
 111
 112       desc = entry->sniffer (this_frame);
 113       if (desc != NULL)
 114         return desc;
 115     }
 116   return table->default_base;
 117 }