ca0d0b529b
generic_func_frame_chain_valid. * gdbarch.h, gdbarch.c: Re-generate. * blockframe.c (generic_func_frame_chain_valid): Only check PC_IN_CALL_DUMMY when generic dummy frames. Don't worry about passing FP to PC_IN_CALL_DUMMY. Fix PR gdb/360.
1564 lines
47 KiB
C
1564 lines
47 KiB
C
/* Get info from stack frames; convert between frames, blocks,
|
||
functions and pc values.
|
||
|
||
Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
|
||
1995, 1996, 1997, 1998, 1999, 2000, 2001, 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. */
|
||
|
||
#include "defs.h"
|
||
#include "symtab.h"
|
||
#include "bfd.h"
|
||
#include "symfile.h"
|
||
#include "objfiles.h"
|
||
#include "frame.h"
|
||
#include "gdbcore.h"
|
||
#include "value.h" /* for read_register */
|
||
#include "target.h" /* for target_has_stack */
|
||
#include "inferior.h" /* for read_pc */
|
||
#include "annotate.h"
|
||
#include "regcache.h"
|
||
#include "gdb_assert.h"
|
||
|
||
/* Prototypes for exported functions. */
|
||
|
||
static void generic_call_dummy_register_unwind (struct frame_info *frame,
|
||
void **cache,
|
||
int regnum,
|
||
int *optimized,
|
||
enum lval_type *lval,
|
||
CORE_ADDR *addrp,
|
||
int *realnum,
|
||
void *raw_buffer);
|
||
static void frame_saved_regs_register_unwind (struct frame_info *frame,
|
||
void **cache,
|
||
int regnum,
|
||
int *optimized,
|
||
enum lval_type *lval,
|
||
CORE_ADDR *addrp,
|
||
int *realnum,
|
||
void *buffer);
|
||
|
||
|
||
void _initialize_blockframe (void);
|
||
|
||
/* A default FRAME_CHAIN_VALID, in the form that is suitable for most
|
||
targets. If FRAME_CHAIN_VALID returns zero it means that the given
|
||
frame is the outermost one and has no caller. */
|
||
|
||
int
|
||
file_frame_chain_valid (CORE_ADDR chain, struct frame_info *thisframe)
|
||
{
|
||
return ((chain) != 0
|
||
&& !inside_entry_file (FRAME_SAVED_PC (thisframe)));
|
||
}
|
||
|
||
/* Use the alternate method of avoiding running up off the end of the
|
||
frame chain or following frames back into the startup code. See
|
||
the comments in objfiles.h. */
|
||
|
||
int
|
||
func_frame_chain_valid (CORE_ADDR chain, struct frame_info *thisframe)
|
||
{
|
||
return ((chain) != 0
|
||
&& !inside_main_func ((thisframe)->pc)
|
||
&& !inside_entry_func ((thisframe)->pc));
|
||
}
|
||
|
||
/* A very simple method of determining a valid frame */
|
||
|
||
int
|
||
nonnull_frame_chain_valid (CORE_ADDR chain, struct frame_info *thisframe)
|
||
{
|
||
return ((chain) != 0);
|
||
}
|
||
|
||
/* Is ADDR inside the startup file? Note that if your machine
|
||
has a way to detect the bottom of the stack, there is no need
|
||
to call this function from FRAME_CHAIN_VALID; the reason for
|
||
doing so is that some machines have no way of detecting bottom
|
||
of stack.
|
||
|
||
A PC of zero is always considered to be the bottom of the stack. */
|
||
|
||
int
|
||
inside_entry_file (CORE_ADDR addr)
|
||
{
|
||
if (addr == 0)
|
||
return 1;
|
||
if (symfile_objfile == 0)
|
||
return 0;
|
||
if (CALL_DUMMY_LOCATION == AT_ENTRY_POINT)
|
||
{
|
||
/* Do not stop backtracing if the pc is in the call dummy
|
||
at the entry point. */
|
||
/* FIXME: Won't always work with zeros for the last two arguments */
|
||
if (PC_IN_CALL_DUMMY (addr, 0, 0))
|
||
return 0;
|
||
}
|
||
return (addr >= symfile_objfile->ei.entry_file_lowpc &&
|
||
addr < symfile_objfile->ei.entry_file_highpc);
|
||
}
|
||
|
||
/* Test a specified PC value to see if it is in the range of addresses
|
||
that correspond to the main() function. See comments above for why
|
||
we might want to do this.
|
||
|
||
Typically called from FRAME_CHAIN_VALID.
|
||
|
||
A PC of zero is always considered to be the bottom of the stack. */
|
||
|
||
int
|
||
inside_main_func (CORE_ADDR pc)
|
||
{
|
||
if (pc == 0)
|
||
return 1;
|
||
if (symfile_objfile == 0)
|
||
return 0;
|
||
|
||
/* If the addr range is not set up at symbol reading time, set it up now.
|
||
This is for FRAME_CHAIN_VALID_ALTERNATE. I do this for coff, because
|
||
it is unable to set it up and symbol reading time. */
|
||
|
||
if (symfile_objfile->ei.main_func_lowpc == INVALID_ENTRY_LOWPC &&
|
||
symfile_objfile->ei.main_func_highpc == INVALID_ENTRY_HIGHPC)
|
||
{
|
||
struct symbol *mainsym;
|
||
|
||
mainsym = lookup_symbol (main_name (), NULL, VAR_NAMESPACE, NULL, NULL);
|
||
if (mainsym && SYMBOL_CLASS (mainsym) == LOC_BLOCK)
|
||
{
|
||
symfile_objfile->ei.main_func_lowpc =
|
||
BLOCK_START (SYMBOL_BLOCK_VALUE (mainsym));
|
||
symfile_objfile->ei.main_func_highpc =
|
||
BLOCK_END (SYMBOL_BLOCK_VALUE (mainsym));
|
||
}
|
||
}
|
||
return (symfile_objfile->ei.main_func_lowpc <= pc &&
|
||
symfile_objfile->ei.main_func_highpc > pc);
|
||
}
|
||
|
||
/* Test a specified PC value to see if it is in the range of addresses
|
||
that correspond to the process entry point function. See comments
|
||
in objfiles.h for why we might want to do this.
|
||
|
||
Typically called from FRAME_CHAIN_VALID.
|
||
|
||
A PC of zero is always considered to be the bottom of the stack. */
|
||
|
||
int
|
||
inside_entry_func (CORE_ADDR pc)
|
||
{
|
||
if (pc == 0)
|
||
return 1;
|
||
if (symfile_objfile == 0)
|
||
return 0;
|
||
if (CALL_DUMMY_LOCATION == AT_ENTRY_POINT)
|
||
{
|
||
/* Do not stop backtracing if the pc is in the call dummy
|
||
at the entry point. */
|
||
/* FIXME: Won't always work with zeros for the last two arguments */
|
||
if (PC_IN_CALL_DUMMY (pc, 0, 0))
|
||
return 0;
|
||
}
|
||
return (symfile_objfile->ei.entry_func_lowpc <= pc &&
|
||
symfile_objfile->ei.entry_func_highpc > pc);
|
||
}
|
||
|
||
/* Info about the innermost stack frame (contents of FP register) */
|
||
|
||
static struct frame_info *current_frame;
|
||
|
||
/* Cache for frame addresses already read by gdb. Valid only while
|
||
inferior is stopped. Control variables for the frame cache should
|
||
be local to this module. */
|
||
|
||
static struct obstack frame_cache_obstack;
|
||
|
||
void *
|
||
frame_obstack_alloc (unsigned long size)
|
||
{
|
||
return obstack_alloc (&frame_cache_obstack, size);
|
||
}
|
||
|
||
void
|
||
frame_saved_regs_zalloc (struct frame_info *fi)
|
||
{
|
||
fi->saved_regs = (CORE_ADDR *)
|
||
frame_obstack_alloc (SIZEOF_FRAME_SAVED_REGS);
|
||
memset (fi->saved_regs, 0, SIZEOF_FRAME_SAVED_REGS);
|
||
}
|
||
|
||
|
||
/* Return the innermost (currently executing) stack frame. */
|
||
|
||
struct frame_info *
|
||
get_current_frame (void)
|
||
{
|
||
if (current_frame == NULL)
|
||
{
|
||
if (target_has_stack)
|
||
current_frame = create_new_frame (read_fp (), read_pc ());
|
||
else
|
||
error ("No stack.");
|
||
}
|
||
return current_frame;
|
||
}
|
||
|
||
void
|
||
set_current_frame (struct frame_info *frame)
|
||
{
|
||
current_frame = frame;
|
||
}
|
||
|
||
|
||
/* Using the PC, select a mechanism for unwinding a frame returning
|
||
the previous frame. The register unwind function should, on
|
||
demand, initialize the ->context object. */
|
||
|
||
static void
|
||
set_unwind_by_pc (CORE_ADDR pc, CORE_ADDR fp,
|
||
frame_register_unwind_ftype **unwind)
|
||
{
|
||
if (!USE_GENERIC_DUMMY_FRAMES)
|
||
/* Still need to set this to something. The ``info frame'' code
|
||
calls this function to find out where the saved registers are.
|
||
Hopefully this is robust enough to stop any core dumps and
|
||
return vaguely correct values.. */
|
||
*unwind = frame_saved_regs_register_unwind;
|
||
else if (PC_IN_CALL_DUMMY (pc, fp, fp))
|
||
*unwind = generic_call_dummy_register_unwind;
|
||
else
|
||
*unwind = frame_saved_regs_register_unwind;
|
||
}
|
||
|
||
/* Create an arbitrary (i.e. address specified by user) or innermost frame.
|
||
Always returns a non-NULL value. */
|
||
|
||
struct frame_info *
|
||
create_new_frame (CORE_ADDR addr, CORE_ADDR pc)
|
||
{
|
||
struct frame_info *fi;
|
||
char *name;
|
||
|
||
fi = (struct frame_info *)
|
||
obstack_alloc (&frame_cache_obstack,
|
||
sizeof (struct frame_info));
|
||
|
||
/* Zero all fields by default. */
|
||
memset (fi, 0, sizeof (struct frame_info));
|
||
|
||
fi->frame = addr;
|
||
fi->pc = pc;
|
||
find_pc_partial_function (pc, &name, (CORE_ADDR *) NULL, (CORE_ADDR *) NULL);
|
||
fi->signal_handler_caller = PC_IN_SIGTRAMP (fi->pc, name);
|
||
|
||
if (INIT_EXTRA_FRAME_INFO_P ())
|
||
INIT_EXTRA_FRAME_INFO (0, fi);
|
||
|
||
/* Select/initialize an unwind function. */
|
||
set_unwind_by_pc (fi->pc, fi->frame, &fi->register_unwind);
|
||
|
||
return fi;
|
||
}
|
||
|
||
/* Return the frame that FRAME calls (NULL if FRAME is the innermost
|
||
frame). */
|
||
|
||
struct frame_info *
|
||
get_next_frame (struct frame_info *frame)
|
||
{
|
||
return frame->next;
|
||
}
|
||
|
||
/* Flush the entire frame cache. */
|
||
|
||
void
|
||
flush_cached_frames (void)
|
||
{
|
||
/* Since we can't really be sure what the first object allocated was */
|
||
obstack_free (&frame_cache_obstack, 0);
|
||
obstack_init (&frame_cache_obstack);
|
||
|
||
current_frame = NULL; /* Invalidate cache */
|
||
select_frame (NULL);
|
||
annotate_frames_invalid ();
|
||
}
|
||
|
||
/* Flush the frame cache, and start a new one if necessary. */
|
||
|
||
void
|
||
reinit_frame_cache (void)
|
||
{
|
||
flush_cached_frames ();
|
||
|
||
/* FIXME: The inferior_ptid test is wrong if there is a corefile. */
|
||
if (PIDGET (inferior_ptid) != 0)
|
||
{
|
||
select_frame (get_current_frame ());
|
||
}
|
||
}
|
||
|
||
/* Return nonzero if the function for this frame lacks a prologue. Many
|
||
machines can define FRAMELESS_FUNCTION_INVOCATION to just call this
|
||
function. */
|
||
|
||
int
|
||
frameless_look_for_prologue (struct frame_info *frame)
|
||
{
|
||
CORE_ADDR func_start, after_prologue;
|
||
|
||
func_start = get_pc_function_start (frame->pc);
|
||
if (func_start)
|
||
{
|
||
func_start += FUNCTION_START_OFFSET;
|
||
/* This is faster, since only care whether there *is* a
|
||
prologue, not how long it is. */
|
||
return PROLOGUE_FRAMELESS_P (func_start);
|
||
}
|
||
else if (frame->pc == 0)
|
||
/* A frame with a zero PC is usually created by dereferencing a
|
||
NULL function pointer, normally causing an immediate core dump
|
||
of the inferior. Mark function as frameless, as the inferior
|
||
has no chance of setting up a stack frame. */
|
||
return 1;
|
||
else
|
||
/* If we can't find the start of the function, we don't really
|
||
know whether the function is frameless, but we should be able
|
||
to get a reasonable (i.e. best we can do under the
|
||
circumstances) backtrace by saying that it isn't. */
|
||
return 0;
|
||
}
|
||
|
||
/* Return a structure containing various interesting information
|
||
about the frame that called NEXT_FRAME. Returns NULL
|
||
if there is no such frame. */
|
||
|
||
struct frame_info *
|
||
get_prev_frame (struct frame_info *next_frame)
|
||
{
|
||
CORE_ADDR address = 0;
|
||
struct frame_info *prev;
|
||
int fromleaf = 0;
|
||
char *name;
|
||
|
||
/* If the requested entry is in the cache, return it.
|
||
Otherwise, figure out what the address should be for the entry
|
||
we're about to add to the cache. */
|
||
|
||
if (!next_frame)
|
||
{
|
||
#if 0
|
||
/* This screws value_of_variable, which just wants a nice clean
|
||
NULL return from block_innermost_frame if there are no frames.
|
||
I don't think I've ever seen this message happen otherwise.
|
||
And returning NULL here is a perfectly legitimate thing to do. */
|
||
if (!current_frame)
|
||
{
|
||
error ("You haven't set up a process's stack to examine.");
|
||
}
|
||
#endif
|
||
|
||
return current_frame;
|
||
}
|
||
|
||
/* If we have the prev one, return it */
|
||
if (next_frame->prev)
|
||
return next_frame->prev;
|
||
|
||
/* On some machines it is possible to call a function without
|
||
setting up a stack frame for it. On these machines, we
|
||
define this macro to take two args; a frameinfo pointer
|
||
identifying a frame and a variable to set or clear if it is
|
||
or isn't leafless. */
|
||
|
||
/* Still don't want to worry about this except on the innermost
|
||
frame. This macro will set FROMLEAF if NEXT_FRAME is a
|
||
frameless function invocation. */
|
||
if (!(next_frame->next))
|
||
{
|
||
fromleaf = FRAMELESS_FUNCTION_INVOCATION (next_frame);
|
||
if (fromleaf)
|
||
address = FRAME_FP (next_frame);
|
||
}
|
||
|
||
if (!fromleaf)
|
||
{
|
||
/* Two macros defined in tm.h specify the machine-dependent
|
||
actions to be performed here.
|
||
First, get the frame's chain-pointer.
|
||
If that is zero, the frame is the outermost frame or a leaf
|
||
called by the outermost frame. This means that if start
|
||
calls main without a frame, we'll return 0 (which is fine
|
||
anyway).
|
||
|
||
Nope; there's a problem. This also returns when the current
|
||
routine is a leaf of main. This is unacceptable. We move
|
||
this to after the ffi test; I'd rather have backtraces from
|
||
start go curfluy than have an abort called from main not show
|
||
main. */
|
||
address = FRAME_CHAIN (next_frame);
|
||
|
||
/* FIXME: cagney/2002-06-08: There should be two tests here.
|
||
The first would check for a valid frame chain based on a user
|
||
selectable policy. The default being ``stop at main'' (as
|
||
implemented by generic_func_frame_chain_valid()). Other
|
||
policies would be available - stop at NULL, .... The second
|
||
test, if provided by the target architecture, would check for
|
||
more exotic cases - most target architectures wouldn't bother
|
||
with this second case. */
|
||
if (!FRAME_CHAIN_VALID (address, next_frame))
|
||
return 0;
|
||
}
|
||
if (address == 0)
|
||
return 0;
|
||
|
||
prev = (struct frame_info *)
|
||
obstack_alloc (&frame_cache_obstack,
|
||
sizeof (struct frame_info));
|
||
|
||
/* Zero all fields by default. */
|
||
memset (prev, 0, sizeof (struct frame_info));
|
||
|
||
if (next_frame)
|
||
next_frame->prev = prev;
|
||
prev->next = next_frame;
|
||
prev->frame = address;
|
||
prev->level = next_frame->level + 1;
|
||
|
||
/* This change should not be needed, FIXME! We should
|
||
determine whether any targets *need* INIT_FRAME_PC to happen
|
||
after INIT_EXTRA_FRAME_INFO and come up with a simple way to
|
||
express what goes on here.
|
||
|
||
INIT_EXTRA_FRAME_INFO is called from two places: create_new_frame
|
||
(where the PC is already set up) and here (where it isn't).
|
||
INIT_FRAME_PC is only called from here, always after
|
||
INIT_EXTRA_FRAME_INFO.
|
||
|
||
The catch is the MIPS, where INIT_EXTRA_FRAME_INFO requires the PC
|
||
value (which hasn't been set yet). Some other machines appear to
|
||
require INIT_EXTRA_FRAME_INFO before they can do INIT_FRAME_PC. Phoo.
|
||
|
||
We shouldn't need INIT_FRAME_PC_FIRST to add more complication to
|
||
an already overcomplicated part of GDB. gnu@cygnus.com, 15Sep92.
|
||
|
||
Assuming that some machines need INIT_FRAME_PC after
|
||
INIT_EXTRA_FRAME_INFO, one possible scheme:
|
||
|
||
SETUP_INNERMOST_FRAME()
|
||
Default version is just create_new_frame (read_fp ()),
|
||
read_pc ()). Machines with extra frame info would do that (or the
|
||
local equivalent) and then set the extra fields.
|
||
SETUP_ARBITRARY_FRAME(argc, argv)
|
||
Only change here is that create_new_frame would no longer init extra
|
||
frame info; SETUP_ARBITRARY_FRAME would have to do that.
|
||
INIT_PREV_FRAME(fromleaf, prev)
|
||
Replace INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC. This should
|
||
also return a flag saying whether to keep the new frame, or
|
||
whether to discard it, because on some machines (e.g. mips) it
|
||
is really awkward to have FRAME_CHAIN_VALID called *before*
|
||
INIT_EXTRA_FRAME_INFO (there is no good way to get information
|
||
deduced in FRAME_CHAIN_VALID into the extra fields of the new frame).
|
||
std_frame_pc(fromleaf, prev)
|
||
This is the default setting for INIT_PREV_FRAME. It just does what
|
||
the default INIT_FRAME_PC does. Some machines will call it from
|
||
INIT_PREV_FRAME (either at the beginning, the end, or in the middle).
|
||
Some machines won't use it.
|
||
kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
|
||
|
||
INIT_FRAME_PC_FIRST (fromleaf, prev);
|
||
|
||
if (INIT_EXTRA_FRAME_INFO_P ())
|
||
INIT_EXTRA_FRAME_INFO (fromleaf, prev);
|
||
|
||
/* This entry is in the frame queue now, which is good since
|
||
FRAME_SAVED_PC may use that queue to figure out its value
|
||
(see tm-sparc.h). We want the pc saved in the inferior frame. */
|
||
INIT_FRAME_PC (fromleaf, prev);
|
||
|
||
/* If ->frame and ->pc are unchanged, we are in the process of getting
|
||
ourselves into an infinite backtrace. Some architectures check this
|
||
in FRAME_CHAIN or thereabouts, but it seems like there is no reason
|
||
this can't be an architecture-independent check. */
|
||
if (next_frame != NULL)
|
||
{
|
||
if (prev->frame == next_frame->frame
|
||
&& prev->pc == next_frame->pc)
|
||
{
|
||
next_frame->prev = NULL;
|
||
obstack_free (&frame_cache_obstack, prev);
|
||
return NULL;
|
||
}
|
||
}
|
||
|
||
/* Initialize the code used to unwind the frame PREV based on the PC
|
||
(and probably other architectural information). The PC lets you
|
||
check things like the debug info at that point (dwarf2cfi?) and
|
||
use that to decide how the frame should be unwound. */
|
||
set_unwind_by_pc (prev->pc, prev->frame, &prev->register_unwind);
|
||
|
||
find_pc_partial_function (prev->pc, &name,
|
||
(CORE_ADDR *) NULL, (CORE_ADDR *) NULL);
|
||
if (PC_IN_SIGTRAMP (prev->pc, name))
|
||
prev->signal_handler_caller = 1;
|
||
|
||
return prev;
|
||
}
|
||
|
||
CORE_ADDR
|
||
get_frame_pc (struct frame_info *frame)
|
||
{
|
||
return frame->pc;
|
||
}
|
||
|
||
|
||
#ifdef FRAME_FIND_SAVED_REGS
|
||
/* XXX - deprecated. This is a compatibility function for targets
|
||
that do not yet implement FRAME_INIT_SAVED_REGS. */
|
||
/* Find the addresses in which registers are saved in FRAME. */
|
||
|
||
void
|
||
get_frame_saved_regs (struct frame_info *frame,
|
||
struct frame_saved_regs *saved_regs_addr)
|
||
{
|
||
if (frame->saved_regs == NULL)
|
||
{
|
||
frame->saved_regs = (CORE_ADDR *)
|
||
frame_obstack_alloc (SIZEOF_FRAME_SAVED_REGS);
|
||
}
|
||
if (saved_regs_addr == NULL)
|
||
{
|
||
struct frame_saved_regs saved_regs;
|
||
FRAME_FIND_SAVED_REGS (frame, saved_regs);
|
||
memcpy (frame->saved_regs, &saved_regs, SIZEOF_FRAME_SAVED_REGS);
|
||
}
|
||
else
|
||
{
|
||
FRAME_FIND_SAVED_REGS (frame, *saved_regs_addr);
|
||
memcpy (frame->saved_regs, saved_regs_addr, SIZEOF_FRAME_SAVED_REGS);
|
||
}
|
||
}
|
||
#endif
|
||
|
||
/* Return the innermost lexical block in execution
|
||
in a specified stack frame. The frame address is assumed valid.
|
||
|
||
If ADDR_IN_BLOCK is non-zero, set *ADDR_IN_BLOCK to the exact code
|
||
address we used to choose the block. We use this to find a source
|
||
line, to decide which macro definitions are in scope.
|
||
|
||
The value returned in *ADDR_IN_BLOCK isn't necessarily the frame's
|
||
PC, and may not really be a valid PC at all. For example, in the
|
||
caller of a function declared to never return, the code at the
|
||
return address will never be reached, so the call instruction may
|
||
be the very last instruction in the block. So the address we use
|
||
to choose the block is actually one byte before the return address
|
||
--- hopefully pointing us at the call instruction, or its delay
|
||
slot instruction. */
|
||
|
||
struct block *
|
||
get_frame_block (struct frame_info *frame, CORE_ADDR *addr_in_block)
|
||
{
|
||
CORE_ADDR pc;
|
||
|
||
pc = frame->pc;
|
||
if (frame->next != 0 && frame->next->signal_handler_caller == 0)
|
||
/* We are not in the innermost frame and we were not interrupted
|
||
by a signal. We need to subtract one to get the correct block,
|
||
in case the call instruction was the last instruction of the block.
|
||
If there are any machines on which the saved pc does not point to
|
||
after the call insn, we probably want to make frame->pc point after
|
||
the call insn anyway. */
|
||
--pc;
|
||
|
||
if (addr_in_block)
|
||
*addr_in_block = pc;
|
||
|
||
return block_for_pc (pc);
|
||
}
|
||
|
||
struct block *
|
||
get_current_block (CORE_ADDR *addr_in_block)
|
||
{
|
||
CORE_ADDR pc = read_pc ();
|
||
|
||
if (addr_in_block)
|
||
*addr_in_block = pc;
|
||
|
||
return block_for_pc (pc);
|
||
}
|
||
|
||
CORE_ADDR
|
||
get_pc_function_start (CORE_ADDR pc)
|
||
{
|
||
register struct block *bl;
|
||
register struct symbol *symbol;
|
||
register struct minimal_symbol *msymbol;
|
||
CORE_ADDR fstart;
|
||
|
||
if ((bl = block_for_pc (pc)) != NULL &&
|
||
(symbol = block_function (bl)) != NULL)
|
||
{
|
||
bl = SYMBOL_BLOCK_VALUE (symbol);
|
||
fstart = BLOCK_START (bl);
|
||
}
|
||
else if ((msymbol = lookup_minimal_symbol_by_pc (pc)) != NULL)
|
||
{
|
||
fstart = SYMBOL_VALUE_ADDRESS (msymbol);
|
||
}
|
||
else
|
||
{
|
||
fstart = 0;
|
||
}
|
||
return (fstart);
|
||
}
|
||
|
||
/* Return the symbol for the function executing in frame FRAME. */
|
||
|
||
struct symbol *
|
||
get_frame_function (struct frame_info *frame)
|
||
{
|
||
register struct block *bl = get_frame_block (frame, 0);
|
||
if (bl == 0)
|
||
return 0;
|
||
return block_function (bl);
|
||
}
|
||
|
||
|
||
/* Return the blockvector immediately containing the innermost lexical block
|
||
containing the specified pc value and section, or 0 if there is none.
|
||
PINDEX is a pointer to the index value of the block. If PINDEX
|
||
is NULL, we don't pass this information back to the caller. */
|
||
|
||
struct blockvector *
|
||
blockvector_for_pc_sect (register CORE_ADDR pc, struct sec *section,
|
||
int *pindex, struct symtab *symtab)
|
||
{
|
||
register struct block *b;
|
||
register int bot, top, half;
|
||
struct blockvector *bl;
|
||
|
||
if (symtab == 0) /* if no symtab specified by caller */
|
||
{
|
||
/* First search all symtabs for one whose file contains our pc */
|
||
if ((symtab = find_pc_sect_symtab (pc, section)) == 0)
|
||
return 0;
|
||
}
|
||
|
||
bl = BLOCKVECTOR (symtab);
|
||
b = BLOCKVECTOR_BLOCK (bl, 0);
|
||
|
||
/* Then search that symtab for the smallest block that wins. */
|
||
/* Use binary search to find the last block that starts before PC. */
|
||
|
||
bot = 0;
|
||
top = BLOCKVECTOR_NBLOCKS (bl);
|
||
|
||
while (top - bot > 1)
|
||
{
|
||
half = (top - bot + 1) >> 1;
|
||
b = BLOCKVECTOR_BLOCK (bl, bot + half);
|
||
if (BLOCK_START (b) <= pc)
|
||
bot += half;
|
||
else
|
||
top = bot + half;
|
||
}
|
||
|
||
/* Now search backward for a block that ends after PC. */
|
||
|
||
while (bot >= 0)
|
||
{
|
||
b = BLOCKVECTOR_BLOCK (bl, bot);
|
||
if (BLOCK_END (b) > pc)
|
||
{
|
||
if (pindex)
|
||
*pindex = bot;
|
||
return bl;
|
||
}
|
||
bot--;
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
/* Return the blockvector immediately containing the innermost lexical block
|
||
containing the specified pc value, or 0 if there is none.
|
||
Backward compatibility, no section. */
|
||
|
||
struct blockvector *
|
||
blockvector_for_pc (register CORE_ADDR pc, int *pindex)
|
||
{
|
||
return blockvector_for_pc_sect (pc, find_pc_mapped_section (pc),
|
||
pindex, NULL);
|
||
}
|
||
|
||
/* Return the innermost lexical block containing the specified pc value
|
||
in the specified section, or 0 if there is none. */
|
||
|
||
struct block *
|
||
block_for_pc_sect (register CORE_ADDR pc, struct sec *section)
|
||
{
|
||
register struct blockvector *bl;
|
||
int index;
|
||
|
||
bl = blockvector_for_pc_sect (pc, section, &index, NULL);
|
||
if (bl)
|
||
return BLOCKVECTOR_BLOCK (bl, index);
|
||
return 0;
|
||
}
|
||
|
||
/* Return the innermost lexical block containing the specified pc value,
|
||
or 0 if there is none. Backward compatibility, no section. */
|
||
|
||
struct block *
|
||
block_for_pc (register CORE_ADDR pc)
|
||
{
|
||
return block_for_pc_sect (pc, find_pc_mapped_section (pc));
|
||
}
|
||
|
||
/* Return the function containing pc value PC in section SECTION.
|
||
Returns 0 if function is not known. */
|
||
|
||
struct symbol *
|
||
find_pc_sect_function (CORE_ADDR pc, struct sec *section)
|
||
{
|
||
register struct block *b = block_for_pc_sect (pc, section);
|
||
if (b == 0)
|
||
return 0;
|
||
return block_function (b);
|
||
}
|
||
|
||
/* Return the function containing pc value PC.
|
||
Returns 0 if function is not known. Backward compatibility, no section */
|
||
|
||
struct symbol *
|
||
find_pc_function (CORE_ADDR pc)
|
||
{
|
||
return find_pc_sect_function (pc, find_pc_mapped_section (pc));
|
||
}
|
||
|
||
/* These variables are used to cache the most recent result
|
||
* of find_pc_partial_function. */
|
||
|
||
static CORE_ADDR cache_pc_function_low = 0;
|
||
static CORE_ADDR cache_pc_function_high = 0;
|
||
static char *cache_pc_function_name = 0;
|
||
static struct sec *cache_pc_function_section = NULL;
|
||
|
||
/* Clear cache, e.g. when symbol table is discarded. */
|
||
|
||
void
|
||
clear_pc_function_cache (void)
|
||
{
|
||
cache_pc_function_low = 0;
|
||
cache_pc_function_high = 0;
|
||
cache_pc_function_name = (char *) 0;
|
||
cache_pc_function_section = NULL;
|
||
}
|
||
|
||
/* Finds the "function" (text symbol) that is smaller than PC but
|
||
greatest of all of the potential text symbols in SECTION. Sets
|
||
*NAME and/or *ADDRESS conditionally if that pointer is non-null.
|
||
If ENDADDR is non-null, then set *ENDADDR to be the end of the
|
||
function (exclusive), but passing ENDADDR as non-null means that
|
||
the function might cause symbols to be read. This function either
|
||
succeeds or fails (not halfway succeeds). If it succeeds, it sets
|
||
*NAME, *ADDRESS, and *ENDADDR to real information and returns 1.
|
||
If it fails, it sets *NAME, *ADDRESS, and *ENDADDR to zero and
|
||
returns 0. */
|
||
|
||
int
|
||
find_pc_sect_partial_function (CORE_ADDR pc, asection *section, char **name,
|
||
CORE_ADDR *address, CORE_ADDR *endaddr)
|
||
{
|
||
struct partial_symtab *pst;
|
||
struct symbol *f;
|
||
struct minimal_symbol *msymbol;
|
||
struct partial_symbol *psb;
|
||
struct obj_section *osect;
|
||
int i;
|
||
CORE_ADDR mapped_pc;
|
||
|
||
mapped_pc = overlay_mapped_address (pc, section);
|
||
|
||
if (mapped_pc >= cache_pc_function_low &&
|
||
mapped_pc < cache_pc_function_high &&
|
||
section == cache_pc_function_section)
|
||
goto return_cached_value;
|
||
|
||
/* If sigtramp is in the u area, it counts as a function (especially
|
||
important for step_1). */
|
||
#if defined SIGTRAMP_START
|
||
if (PC_IN_SIGTRAMP (mapped_pc, (char *) NULL))
|
||
{
|
||
cache_pc_function_low = SIGTRAMP_START (mapped_pc);
|
||
cache_pc_function_high = SIGTRAMP_END (mapped_pc);
|
||
cache_pc_function_name = "<sigtramp>";
|
||
cache_pc_function_section = section;
|
||
goto return_cached_value;
|
||
}
|
||
#endif
|
||
|
||
msymbol = lookup_minimal_symbol_by_pc_section (mapped_pc, section);
|
||
pst = find_pc_sect_psymtab (mapped_pc, section);
|
||
if (pst)
|
||
{
|
||
/* Need to read the symbols to get a good value for the end address. */
|
||
if (endaddr != NULL && !pst->readin)
|
||
{
|
||
/* Need to get the terminal in case symbol-reading produces
|
||
output. */
|
||
target_terminal_ours_for_output ();
|
||
PSYMTAB_TO_SYMTAB (pst);
|
||
}
|
||
|
||
if (pst->readin)
|
||
{
|
||
/* Checking whether the msymbol has a larger value is for the
|
||
"pathological" case mentioned in print_frame_info. */
|
||
f = find_pc_sect_function (mapped_pc, section);
|
||
if (f != NULL
|
||
&& (msymbol == NULL
|
||
|| (BLOCK_START (SYMBOL_BLOCK_VALUE (f))
|
||
>= SYMBOL_VALUE_ADDRESS (msymbol))))
|
||
{
|
||
cache_pc_function_low = BLOCK_START (SYMBOL_BLOCK_VALUE (f));
|
||
cache_pc_function_high = BLOCK_END (SYMBOL_BLOCK_VALUE (f));
|
||
cache_pc_function_name = SYMBOL_NAME (f);
|
||
cache_pc_function_section = section;
|
||
goto return_cached_value;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* Now that static symbols go in the minimal symbol table, perhaps
|
||
we could just ignore the partial symbols. But at least for now
|
||
we use the partial or minimal symbol, whichever is larger. */
|
||
psb = find_pc_sect_psymbol (pst, mapped_pc, section);
|
||
|
||
if (psb
|
||
&& (msymbol == NULL ||
|
||
(SYMBOL_VALUE_ADDRESS (psb)
|
||
>= SYMBOL_VALUE_ADDRESS (msymbol))))
|
||
{
|
||
/* This case isn't being cached currently. */
|
||
if (address)
|
||
*address = SYMBOL_VALUE_ADDRESS (psb);
|
||
if (name)
|
||
*name = SYMBOL_NAME (psb);
|
||
/* endaddr non-NULL can't happen here. */
|
||
return 1;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Not in the normal symbol tables, see if the pc is in a known section.
|
||
If it's not, then give up. This ensures that anything beyond the end
|
||
of the text seg doesn't appear to be part of the last function in the
|
||
text segment. */
|
||
|
||
osect = find_pc_sect_section (mapped_pc, section);
|
||
|
||
if (!osect)
|
||
msymbol = NULL;
|
||
|
||
/* Must be in the minimal symbol table. */
|
||
if (msymbol == NULL)
|
||
{
|
||
/* No available symbol. */
|
||
if (name != NULL)
|
||
*name = 0;
|
||
if (address != NULL)
|
||
*address = 0;
|
||
if (endaddr != NULL)
|
||
*endaddr = 0;
|
||
return 0;
|
||
}
|
||
|
||
cache_pc_function_low = SYMBOL_VALUE_ADDRESS (msymbol);
|
||
cache_pc_function_name = SYMBOL_NAME (msymbol);
|
||
cache_pc_function_section = section;
|
||
|
||
/* Use the lesser of the next minimal symbol in the same section, or
|
||
the end of the section, as the end of the function. */
|
||
|
||
/* Step over other symbols at this same address, and symbols in
|
||
other sections, to find the next symbol in this section with
|
||
a different address. */
|
||
|
||
for (i = 1; SYMBOL_NAME (msymbol + i) != NULL; i++)
|
||
{
|
||
if (SYMBOL_VALUE_ADDRESS (msymbol + i) != SYMBOL_VALUE_ADDRESS (msymbol)
|
||
&& SYMBOL_BFD_SECTION (msymbol + i) == SYMBOL_BFD_SECTION (msymbol))
|
||
break;
|
||
}
|
||
|
||
if (SYMBOL_NAME (msymbol + i) != NULL
|
||
&& SYMBOL_VALUE_ADDRESS (msymbol + i) < osect->endaddr)
|
||
cache_pc_function_high = SYMBOL_VALUE_ADDRESS (msymbol + i);
|
||
else
|
||
/* We got the start address from the last msymbol in the objfile.
|
||
So the end address is the end of the section. */
|
||
cache_pc_function_high = osect->endaddr;
|
||
|
||
return_cached_value:
|
||
|
||
if (address)
|
||
{
|
||
if (pc_in_unmapped_range (pc, section))
|
||
*address = overlay_unmapped_address (cache_pc_function_low, section);
|
||
else
|
||
*address = cache_pc_function_low;
|
||
}
|
||
|
||
if (name)
|
||
*name = cache_pc_function_name;
|
||
|
||
if (endaddr)
|
||
{
|
||
if (pc_in_unmapped_range (pc, section))
|
||
{
|
||
/* Because the high address is actually beyond the end of
|
||
the function (and therefore possibly beyond the end of
|
||
the overlay), we must actually convert (high - 1)
|
||
and then add one to that. */
|
||
|
||
*endaddr = 1 + overlay_unmapped_address (cache_pc_function_high - 1,
|
||
section);
|
||
}
|
||
else
|
||
*endaddr = cache_pc_function_high;
|
||
}
|
||
|
||
return 1;
|
||
}
|
||
|
||
/* Backward compatibility, no section argument */
|
||
|
||
int
|
||
find_pc_partial_function (CORE_ADDR pc, char **name, CORE_ADDR *address,
|
||
CORE_ADDR *endaddr)
|
||
{
|
||
asection *section;
|
||
|
||
section = find_pc_overlay (pc);
|
||
return find_pc_sect_partial_function (pc, section, name, address, endaddr);
|
||
}
|
||
|
||
/* Return the innermost stack frame executing inside of BLOCK,
|
||
or NULL if there is no such frame. If BLOCK is NULL, just return NULL. */
|
||
|
||
struct frame_info *
|
||
block_innermost_frame (struct block *block)
|
||
{
|
||
struct frame_info *frame;
|
||
register CORE_ADDR start;
|
||
register CORE_ADDR end;
|
||
|
||
if (block == NULL)
|
||
return NULL;
|
||
|
||
start = BLOCK_START (block);
|
||
end = BLOCK_END (block);
|
||
|
||
frame = NULL;
|
||
while (1)
|
||
{
|
||
frame = get_prev_frame (frame);
|
||
if (frame == NULL)
|
||
return NULL;
|
||
if (frame->pc >= start && frame->pc < end)
|
||
return frame;
|
||
}
|
||
}
|
||
|
||
/* Return the full FRAME which corresponds to the given CORE_ADDR
|
||
or NULL if no FRAME on the chain corresponds to CORE_ADDR. */
|
||
|
||
struct frame_info *
|
||
find_frame_addr_in_frame_chain (CORE_ADDR frame_addr)
|
||
{
|
||
struct frame_info *frame = NULL;
|
||
|
||
if (frame_addr == (CORE_ADDR) 0)
|
||
return NULL;
|
||
|
||
while (1)
|
||
{
|
||
frame = get_prev_frame (frame);
|
||
if (frame == NULL)
|
||
return NULL;
|
||
if (FRAME_FP (frame) == frame_addr)
|
||
return frame;
|
||
}
|
||
}
|
||
|
||
#ifdef SIGCONTEXT_PC_OFFSET
|
||
/* Get saved user PC for sigtramp from sigcontext for BSD style sigtramp. */
|
||
|
||
CORE_ADDR
|
||
sigtramp_saved_pc (struct frame_info *frame)
|
||
{
|
||
CORE_ADDR sigcontext_addr;
|
||
char *buf;
|
||
int ptrbytes = TARGET_PTR_BIT / TARGET_CHAR_BIT;
|
||
int sigcontext_offs = (2 * TARGET_INT_BIT) / TARGET_CHAR_BIT;
|
||
|
||
buf = alloca (ptrbytes);
|
||
/* Get sigcontext address, it is the third parameter on the stack. */
|
||
if (frame->next)
|
||
sigcontext_addr = read_memory_integer (FRAME_ARGS_ADDRESS (frame->next)
|
||
+ FRAME_ARGS_SKIP
|
||
+ sigcontext_offs,
|
||
ptrbytes);
|
||
else
|
||
sigcontext_addr = read_memory_integer (read_register (SP_REGNUM)
|
||
+ sigcontext_offs,
|
||
ptrbytes);
|
||
|
||
/* Don't cause a memory_error when accessing sigcontext in case the stack
|
||
layout has changed or the stack is corrupt. */
|
||
target_read_memory (sigcontext_addr + SIGCONTEXT_PC_OFFSET, buf, ptrbytes);
|
||
return extract_unsigned_integer (buf, ptrbytes);
|
||
}
|
||
#endif /* SIGCONTEXT_PC_OFFSET */
|
||
|
||
|
||
/* Are we in a call dummy? The code below which allows DECR_PC_AFTER_BREAK
|
||
below is for infrun.c, which may give the macro a pc without that
|
||
subtracted out. */
|
||
|
||
extern CORE_ADDR text_end;
|
||
|
||
int
|
||
pc_in_call_dummy_before_text_end (CORE_ADDR pc, CORE_ADDR sp,
|
||
CORE_ADDR frame_address)
|
||
{
|
||
return ((pc) >= text_end - CALL_DUMMY_LENGTH
|
||
&& (pc) <= text_end + DECR_PC_AFTER_BREAK);
|
||
}
|
||
|
||
int
|
||
pc_in_call_dummy_after_text_end (CORE_ADDR pc, CORE_ADDR sp,
|
||
CORE_ADDR frame_address)
|
||
{
|
||
return ((pc) >= text_end
|
||
&& (pc) <= text_end + CALL_DUMMY_LENGTH + DECR_PC_AFTER_BREAK);
|
||
}
|
||
|
||
/* Is the PC in a call dummy? SP and FRAME_ADDRESS are the bottom and
|
||
top of the stack frame which we are checking, where "bottom" and
|
||
"top" refer to some section of memory which contains the code for
|
||
the call dummy. Calls to this macro assume that the contents of
|
||
SP_REGNUM and FP_REGNUM (or the saved values thereof), respectively,
|
||
are the things to pass.
|
||
|
||
This won't work on the 29k, where SP_REGNUM and FP_REGNUM don't
|
||
have that meaning, but the 29k doesn't use ON_STACK. This could be
|
||
fixed by generalizing this scheme, perhaps by passing in a frame
|
||
and adding a few fields, at least on machines which need them for
|
||
PC_IN_CALL_DUMMY.
|
||
|
||
Something simpler, like checking for the stack segment, doesn't work,
|
||
since various programs (threads implementations, gcc nested function
|
||
stubs, etc) may either allocate stack frames in another segment, or
|
||
allocate other kinds of code on the stack. */
|
||
|
||
int
|
||
pc_in_call_dummy_on_stack (CORE_ADDR pc, CORE_ADDR sp, CORE_ADDR frame_address)
|
||
{
|
||
return (INNER_THAN ((sp), (pc))
|
||
&& (frame_address != 0)
|
||
&& INNER_THAN ((pc), (frame_address)));
|
||
}
|
||
|
||
int
|
||
pc_in_call_dummy_at_entry_point (CORE_ADDR pc, CORE_ADDR sp,
|
||
CORE_ADDR frame_address)
|
||
{
|
||
return ((pc) >= CALL_DUMMY_ADDRESS ()
|
||
&& (pc) <= (CALL_DUMMY_ADDRESS () + DECR_PC_AFTER_BREAK));
|
||
}
|
||
|
||
|
||
/*
|
||
* 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, 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 FRAME_CHAIN_VALID as
|
||
* generic_{file,func}_frame_chain_valid and FIX_CALL_DUMMY as
|
||
* generic_fix_call_dummy. */
|
||
|
||
/* Dummy frame. This saves the processor state just prior to setting
|
||
up the inferior function call. Older targets save the registers
|
||
on the target stack (but that really slows down function calls). */
|
||
|
||
struct dummy_frame
|
||
{
|
||
struct dummy_frame *next;
|
||
|
||
CORE_ADDR pc;
|
||
CORE_ADDR fp;
|
||
CORE_ADDR sp;
|
||
CORE_ADDR top;
|
||
char *registers;
|
||
|
||
/* Address range of the call dummy code. Look for PC in the range
|
||
[LO..HI) (after allowing for DECR_PC_AFTER_BREAK). */
|
||
CORE_ADDR call_lo;
|
||
CORE_ADDR call_hi;
|
||
};
|
||
|
||
static struct dummy_frame *dummy_frame_stack = NULL;
|
||
|
||
/* Function: find_dummy_frame(pc, fp, sp)
|
||
|
||
Search the stack of dummy frames for one matching the given PC, FP
|
||
and SP. Unlike PC_IN_CALL_DUMMY, this function doesn't need to
|
||
adjust for DECR_PC_AFTER_BREAK. This is because it is only legal
|
||
to call this function after the PC has been adjusted. */
|
||
|
||
char *
|
||
generic_find_dummy_frame (CORE_ADDR pc, CORE_ADDR fp)
|
||
{
|
||
struct dummy_frame *dummyframe;
|
||
|
||
for (dummyframe = dummy_frame_stack; dummyframe != NULL;
|
||
dummyframe = dummyframe->next)
|
||
if ((pc >= dummyframe->call_lo && pc < dummyframe->call_hi)
|
||
&& (fp == dummyframe->fp
|
||
|| fp == dummyframe->sp
|
||
|| fp == dummyframe->top))
|
||
/* The frame in question lies between the saved fp and sp, inclusive */
|
||
return dummyframe->registers;
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Function: pc_in_call_dummy (pc, sp, fp)
|
||
|
||
Return true if the PC falls in a dummy frame created by gdb for an
|
||
inferior call. The code below which allows DECR_PC_AFTER_BREAK is
|
||
for infrun.c, which may give the function a PC without that
|
||
subtracted out. */
|
||
|
||
int
|
||
generic_pc_in_call_dummy (CORE_ADDR pc, CORE_ADDR sp, CORE_ADDR fp)
|
||
{
|
||
struct dummy_frame *dummyframe;
|
||
for (dummyframe = dummy_frame_stack;
|
||
dummyframe != NULL;
|
||
dummyframe = dummyframe->next)
|
||
{
|
||
if ((pc >= dummyframe->call_lo)
|
||
&& (pc < dummyframe->call_hi + DECR_PC_AFTER_BREAK))
|
||
return 1;
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
/* Function: read_register_dummy
|
||
Find a saved register from before GDB calls a function in the inferior */
|
||
|
||
CORE_ADDR
|
||
generic_read_register_dummy (CORE_ADDR pc, CORE_ADDR fp, int regno)
|
||
{
|
||
char *dummy_regs = generic_find_dummy_frame (pc, fp);
|
||
|
||
if (dummy_regs)
|
||
return extract_address (&dummy_regs[REGISTER_BYTE (regno)],
|
||
REGISTER_RAW_SIZE (regno));
|
||
else
|
||
return 0;
|
||
}
|
||
|
||
/* Save all the registers on the dummy frame stack. Most ports save the
|
||
registers on the target stack. This results in lots of unnecessary memory
|
||
references, which are slow when debugging via a serial line. Instead, we
|
||
save all the registers internally, and never write them to the stack. The
|
||
registers get restored when the called function returns to the entry point,
|
||
where a breakpoint is laying in wait. */
|
||
|
||
void
|
||
generic_push_dummy_frame (void)
|
||
{
|
||
struct dummy_frame *dummy_frame;
|
||
CORE_ADDR fp = (get_current_frame ())->frame;
|
||
|
||
/* check to see if there are stale dummy frames,
|
||
perhaps left over from when a longjump took us out of a
|
||
function that was called by the debugger */
|
||
|
||
dummy_frame = dummy_frame_stack;
|
||
while (dummy_frame)
|
||
if (INNER_THAN (dummy_frame->fp, fp)) /* stale -- destroy! */
|
||
{
|
||
dummy_frame_stack = dummy_frame->next;
|
||
xfree (dummy_frame->registers);
|
||
xfree (dummy_frame);
|
||
dummy_frame = dummy_frame_stack;
|
||
}
|
||
else
|
||
dummy_frame = dummy_frame->next;
|
||
|
||
dummy_frame = xmalloc (sizeof (struct dummy_frame));
|
||
dummy_frame->registers = xmalloc (REGISTER_BYTES);
|
||
|
||
dummy_frame->pc = read_pc ();
|
||
dummy_frame->sp = read_sp ();
|
||
dummy_frame->top = dummy_frame->sp;
|
||
dummy_frame->fp = fp;
|
||
read_register_bytes (0, dummy_frame->registers, REGISTER_BYTES);
|
||
dummy_frame->next = dummy_frame_stack;
|
||
dummy_frame_stack = dummy_frame;
|
||
}
|
||
|
||
void
|
||
generic_save_dummy_frame_tos (CORE_ADDR sp)
|
||
{
|
||
dummy_frame_stack->top = sp;
|
||
}
|
||
|
||
/* Record the upper/lower bounds on the address of the call dummy. */
|
||
|
||
void
|
||
generic_save_call_dummy_addr (CORE_ADDR lo, CORE_ADDR hi)
|
||
{
|
||
dummy_frame_stack->call_lo = lo;
|
||
dummy_frame_stack->call_hi = hi;
|
||
}
|
||
|
||
/* Restore the machine state from either the saved dummy stack or a
|
||
real stack frame. */
|
||
|
||
void
|
||
generic_pop_current_frame (void (*popper) (struct frame_info * frame))
|
||
{
|
||
struct frame_info *frame = get_current_frame ();
|
||
|
||
if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
|
||
generic_pop_dummy_frame ();
|
||
else
|
||
(*popper) (frame);
|
||
}
|
||
|
||
/* Function: pop_dummy_frame
|
||
Restore the machine state from a saved dummy stack frame. */
|
||
|
||
void
|
||
generic_pop_dummy_frame (void)
|
||
{
|
||
struct dummy_frame *dummy_frame = dummy_frame_stack;
|
||
|
||
/* FIXME: what if the first frame isn't the right one, eg..
|
||
because one call-by-hand function has done a longjmp into another one? */
|
||
|
||
if (!dummy_frame)
|
||
error ("Can't pop dummy frame!");
|
||
dummy_frame_stack = dummy_frame->next;
|
||
write_register_bytes (0, dummy_frame->registers, REGISTER_BYTES);
|
||
flush_cached_frames ();
|
||
|
||
xfree (dummy_frame->registers);
|
||
xfree (dummy_frame);
|
||
}
|
||
|
||
/* Function: frame_chain_valid
|
||
Returns true for a user frame or a call_function_by_hand dummy frame,
|
||
and false for the CRT0 start-up frame. Purpose is to terminate backtrace */
|
||
|
||
int
|
||
generic_file_frame_chain_valid (CORE_ADDR fp, struct frame_info *fi)
|
||
{
|
||
if (PC_IN_CALL_DUMMY (FRAME_SAVED_PC (fi), fp, fp))
|
||
return 1; /* don't prune CALL_DUMMY frames */
|
||
else /* fall back to default algorithm (see frame.h) */
|
||
return (fp != 0
|
||
&& (INNER_THAN (fi->frame, fp) || fi->frame == fp)
|
||
&& !inside_entry_file (FRAME_SAVED_PC (fi)));
|
||
}
|
||
|
||
int
|
||
generic_func_frame_chain_valid (CORE_ADDR fp, struct frame_info *fi)
|
||
{
|
||
if (USE_GENERIC_DUMMY_FRAMES
|
||
&& PC_IN_CALL_DUMMY ((fi)->pc, 0, 0))
|
||
return 1; /* don't prune CALL_DUMMY frames */
|
||
else /* fall back to default algorithm (see frame.h) */
|
||
return (fp != 0
|
||
&& (INNER_THAN (fi->frame, fp) || fi->frame == fp)
|
||
&& !inside_main_func ((fi)->pc)
|
||
&& !inside_entry_func ((fi)->pc));
|
||
}
|
||
|
||
/* Function: fix_call_dummy
|
||
Stub function. Generic dummy frames typically do not need to fix
|
||
the frame being created */
|
||
|
||
void
|
||
generic_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs,
|
||
struct value **args, struct type *type, int gcc_p)
|
||
{
|
||
return;
|
||
}
|
||
|
||
/* Given a call-dummy dummy-frame, return the registers. Here the
|
||
register value is taken from the local copy of the register buffer. */
|
||
|
||
static void
|
||
generic_call_dummy_register_unwind (struct frame_info *frame, void **cache,
|
||
int regnum, int *optimized,
|
||
enum lval_type *lvalp, CORE_ADDR *addrp,
|
||
int *realnum, void *bufferp)
|
||
{
|
||
gdb_assert (frame != NULL);
|
||
gdb_assert (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame));
|
||
|
||
/* Describe the register's location. Generic dummy frames always
|
||
have the register value in an ``expression''. */
|
||
*optimized = 0;
|
||
*lvalp = not_lval;
|
||
*addrp = 0;
|
||
*realnum = -1;
|
||
|
||
/* If needed, find and return the value of the register. */
|
||
if (bufferp != NULL)
|
||
{
|
||
char *registers;
|
||
#if 1
|
||
/* Get the address of the register buffer that contains all the
|
||
saved registers for this dummy frame. Cache that address. */
|
||
registers = (*cache);
|
||
if (registers == NULL)
|
||
{
|
||
registers = generic_find_dummy_frame (frame->pc, frame->frame);
|
||
(*cache) = registers;
|
||
}
|
||
#else
|
||
/* Get the address of the register buffer that contains the
|
||
saved registers and then extract the value from that. */
|
||
registers = generic_find_dummy_frame (frame->pc, frame->frame);
|
||
#endif
|
||
gdb_assert (registers != NULL);
|
||
/* Return the actual value. */
|
||
memcpy (bufferp, registers + REGISTER_BYTE (regnum),
|
||
REGISTER_RAW_SIZE (regnum));
|
||
}
|
||
}
|
||
|
||
/* Return the register saved in the simplistic ``saved_regs'' cache.
|
||
If the value isn't here AND a value is needed, try the next inner
|
||
most frame. */
|
||
|
||
static void
|
||
frame_saved_regs_register_unwind (struct frame_info *frame, void **cache,
|
||
int regnum, int *optimizedp,
|
||
enum lval_type *lvalp, CORE_ADDR *addrp,
|
||
int *realnump, void *bufferp)
|
||
{
|
||
/* There is always a frame at this point. And THIS is the frame
|
||
we're interested in. */
|
||
gdb_assert (frame != NULL);
|
||
gdb_assert (!PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame));
|
||
|
||
/* Load the saved_regs register cache. */
|
||
if (frame->saved_regs == NULL)
|
||
FRAME_INIT_SAVED_REGS (frame);
|
||
|
||
if (frame->saved_regs != NULL
|
||
&& frame->saved_regs[regnum] != 0)
|
||
{
|
||
if (regnum == SP_REGNUM)
|
||
{
|
||
/* SP register treated specially. */
|
||
*optimizedp = 0;
|
||
*lvalp = not_lval;
|
||
*addrp = 0;
|
||
*realnump = -1;
|
||
if (bufferp != NULL)
|
||
store_address (bufferp, REGISTER_RAW_SIZE (regnum),
|
||
frame->saved_regs[regnum]);
|
||
}
|
||
else
|
||
{
|
||
/* Any other register is saved in memory, fetch it but cache
|
||
a local copy of its value. */
|
||
*optimizedp = 0;
|
||
*lvalp = lval_memory;
|
||
*addrp = frame->saved_regs[regnum];
|
||
*realnump = -1;
|
||
if (bufferp != NULL)
|
||
{
|
||
#if 1
|
||
/* Save each register value, as it is read in, in a
|
||
frame based cache. */
|
||
void **regs = (*cache);
|
||
if (regs == NULL)
|
||
{
|
||
int sizeof_cache = ((NUM_REGS + NUM_PSEUDO_REGS)
|
||
* sizeof (void *));
|
||
regs = frame_obstack_alloc (sizeof_cache);
|
||
memset (regs, 0, sizeof_cache);
|
||
(*cache) = regs;
|
||
}
|
||
if (regs[regnum] == NULL)
|
||
{
|
||
regs[regnum]
|
||
= frame_obstack_alloc (REGISTER_RAW_SIZE (regnum));
|
||
read_memory (frame->saved_regs[regnum], regs[regnum],
|
||
REGISTER_RAW_SIZE (regnum));
|
||
}
|
||
memcpy (bufferp, regs[regnum], REGISTER_RAW_SIZE (regnum));
|
||
#else
|
||
/* Read the value in from memory. */
|
||
read_memory (frame->saved_regs[regnum], bufferp,
|
||
REGISTER_RAW_SIZE (regnum));
|
||
#endif
|
||
}
|
||
}
|
||
return;
|
||
}
|
||
|
||
/* No luck, assume this and the next frame have the same register
|
||
value. If a value is needed, pass the request on down the chain;
|
||
otherwise just return an indication that the value is in the same
|
||
register as the next frame. */
|
||
if (bufferp == NULL)
|
||
{
|
||
*optimizedp = 0;
|
||
*lvalp = lval_register;
|
||
*addrp = 0;
|
||
*realnump = regnum;
|
||
}
|
||
else
|
||
{
|
||
frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp,
|
||
realnump, bufferp);
|
||
}
|
||
}
|
||
|
||
/* Function: get_saved_register
|
||
Find register number REGNUM relative to FRAME and put its (raw,
|
||
target format) contents in *RAW_BUFFER.
|
||
|
||
Set *OPTIMIZED if the variable was optimized out (and thus can't be
|
||
fetched). Note that this is never set to anything other than zero
|
||
in this implementation.
|
||
|
||
Set *LVAL to lval_memory, lval_register, or not_lval, depending on
|
||
whether the value was fetched from memory, from a register, or in a
|
||
strange and non-modifiable way (e.g. a frame pointer which was
|
||
calculated rather than fetched). We will use not_lval for values
|
||
fetched from generic dummy frames.
|
||
|
||
Set *ADDRP to the address, either in memory or as a REGISTER_BYTE
|
||
offset into the registers array. If the value is stored in a dummy
|
||
frame, set *ADDRP to zero.
|
||
|
||
To use this implementation, define a function called
|
||
"get_saved_register" in your target code, which simply passes all
|
||
of its arguments to this function.
|
||
|
||
The argument RAW_BUFFER must point to aligned memory. */
|
||
|
||
void
|
||
generic_get_saved_register (char *raw_buffer, int *optimized, CORE_ADDR *addrp,
|
||
struct frame_info *frame, int regnum,
|
||
enum lval_type *lval)
|
||
{
|
||
if (!target_has_registers)
|
||
error ("No registers.");
|
||
|
||
/* Normal systems don't optimize out things with register numbers. */
|
||
if (optimized != NULL)
|
||
*optimized = 0;
|
||
|
||
if (addrp) /* default assumption: not found in memory */
|
||
*addrp = 0;
|
||
|
||
/* Note: since the current frame's registers could only have been
|
||
saved by frames INTERIOR TO the current frame, we skip examining
|
||
the current frame itself: otherwise, we would be getting the
|
||
previous frame's registers which were saved by the current frame. */
|
||
|
||
while (frame && ((frame = frame->next) != NULL))
|
||
{
|
||
if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
|
||
{
|
||
if (lval) /* found it in a CALL_DUMMY frame */
|
||
*lval = not_lval;
|
||
if (raw_buffer)
|
||
memcpy (raw_buffer,
|
||
generic_find_dummy_frame (frame->pc, frame->frame) +
|
||
REGISTER_BYTE (regnum),
|
||
REGISTER_RAW_SIZE (regnum));
|
||
return;
|
||
}
|
||
|
||
FRAME_INIT_SAVED_REGS (frame);
|
||
if (frame->saved_regs != NULL
|
||
&& frame->saved_regs[regnum] != 0)
|
||
{
|
||
if (lval) /* found it saved on the stack */
|
||
*lval = lval_memory;
|
||
if (regnum == SP_REGNUM)
|
||
{
|
||
if (raw_buffer) /* SP register treated specially */
|
||
store_address (raw_buffer, REGISTER_RAW_SIZE (regnum),
|
||
frame->saved_regs[regnum]);
|
||
}
|
||
else
|
||
{
|
||
if (addrp) /* any other register */
|
||
*addrp = frame->saved_regs[regnum];
|
||
if (raw_buffer)
|
||
read_memory (frame->saved_regs[regnum], raw_buffer,
|
||
REGISTER_RAW_SIZE (regnum));
|
||
}
|
||
return;
|
||
}
|
||
}
|
||
|
||
/* If we get thru the loop to this point, it means the register was
|
||
not saved in any frame. Return the actual live-register value. */
|
||
|
||
if (lval) /* found it in a live register */
|
||
*lval = lval_register;
|
||
if (addrp)
|
||
*addrp = REGISTER_BYTE (regnum);
|
||
if (raw_buffer)
|
||
read_register_gen (regnum, raw_buffer);
|
||
}
|
||
|
||
void
|
||
_initialize_blockframe (void)
|
||
{
|
||
obstack_init (&frame_cache_obstack);
|
||
}
|