binutils-gdb/gdb/dummy-frame.h

87 lines
3.4 KiB
C

/* Code dealing with dummy stack frames, for GDB, the GNU debugger.
Copyright 2002 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 2 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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#if !defined (DUMMY_FRAME_H)
#define DUMMY_FRAME_H 1
struct frame_info;
struct regcache;
struct frame_unwind;
struct frame_id;
/* GENERIC DUMMY FRAMES
The following code serves to maintain the dummy stack frames for
inferior function calls (ie. when gdb calls into the inferior via
call_function_by_hand). This code saves the machine state before
the call in host memory, so we must maintain an independent stack
and keep it consistant etc. I am attempting to make this code
generic enough to be used by many targets.
The cheapest and most generic way to do CALL_DUMMY on a new target
is probably to define CALL_DUMMY to be empty,
DEPRECATED_CALL_DUMMY_LENGTH to zero, and CALL_DUMMY_LOCATION to
AT_ENTRY. Then you must remember to define PUSH_RETURN_ADDRESS,
because no call instruction will be being executed by the target.
Also DEPRECATED_FRAME_CHAIN_VALID as
generic_{file,func}_frame_chain_valid and do not set
DEPRECATED_FIX_CALL_DUMMY. */
/* If the PC falls in a dummy frame, return a dummy frame
unwinder. */
extern const struct frame_unwind *dummy_frame_sniffer (struct frame_info *next_frame);
/* Does the PC fall in a dummy frame?
This function is used by "frame.c" when creating a new `struct
frame_info'.
Note that there is also very similar code in breakpoint.c (where
the bpstat stop reason is computed). It is looking for a PC
falling on a dummy_frame breakpoint. Perhaphs this, and that code
should be combined?
Architecture dependant code, that has access to a frame, should not
use this function. Instead (get_frame_type() == DUMMY_FRAME)
should be used.
Hmm, but what about threads? When the dummy-frame code tries to
relocate a dummy frame's saved registers it definitly needs to
differentiate between threads (otherwize it will do things like
clean-up the wrong threads frames). However, when just trying to
identify a dummy-frame that shouldn't matter. The wost that can
happen is that a thread is marked as sitting in a dummy frame when,
in reality, its corrupted its stack, to the point that a PC is
pointing into a dummy frame. */
extern int pc_in_dummy_frame (CORE_ADDR pc);
/* Return the regcache that belongs to the dummy-frame identifed by PC
and FP, or NULL if no such frame exists. */
/* FIXME: cagney/2002-11-08: The function only exists because of
deprecated_generic_get_saved_register. Eliminate that function and
this, to, can go. */
extern struct regcache *deprecated_find_dummy_frame_regcache (CORE_ADDR pc,
CORE_ADDR fp);
#endif /* !defined (DUMMY_FRAME_H) */