* blockframe.c, frame.h (sigtramp_saved_pc): New routine to fetch

the saved pc from sigcontext on the stack for BSD signal handling.
	* config/i386/tm-i386bsd.h (SIGTRAMP_START, SIGTRAMP_END, FRAME_CHAIN,
	FRAMELESS_FUNCTION_INVOCATION, FRAME_SAVED_PC, SIGCONTEXT_PC_OFFSET):
	Define to make backtracing through sigtramp work.
	* config/vax/tm-vax.h (SIGTRAMP_START, SIGTRAMP_END, TARGET_UPAGES,
	FRAME_SAVED_PC, SIGCONTEXT_PC_OFFSET):  Ditto.
This commit is contained in:
Peter Schauer 1993-08-17 08:47:25 +00:00
parent b606bd8df4
commit d541211d61
3 changed files with 342 additions and 134 deletions

View File

@ -1,5 +1,18 @@
Tue Aug 17 01:43:55 1993 Peter Schauer (pes@regent.e-technik.tu-muenchen.de)
* blockframe.c, frame.h (sigtramp_saved_pc): New routine to fetch
the saved pc from sigcontext on the stack for BSD signal handling.
* config/i386/tm-i386bsd.h (SIGTRAMP_START, SIGTRAMP_END, FRAME_CHAIN,
FRAMELESS_FUNCTION_INVOCATION, FRAME_SAVED_PC, SIGCONTEXT_PC_OFFSET):
Define to make backtracing through sigtramp work.
* config/vax/tm-vax.h (SIGTRAMP_START, SIGTRAMP_END, TARGET_UPAGES,
FRAME_SAVED_PC, SIGCONTEXT_PC_OFFSET): Ditto.
Mon Aug 16 13:52:14 1993 Jim Kingdon (kingdon@lioth.cygnus.com)
* target.c (target_xfer_memory): Clear errno before calling
to_xfer_memory.
* stack.c (frame_info, print_frame_info): Add comment about using
the starting source line number on a line boundary if backtracing
through sigtramp.

View File

@ -124,6 +124,7 @@ create_new_frame (addr, pc)
CORE_ADDR pc;
{
struct frame_info *fci; /* Same type as FRAME */
char *name;
fci = (struct frame_info *)
obstack_alloc (&frame_cache_obstack,
@ -134,7 +135,8 @@ create_new_frame (addr, pc)
fci->prev = (struct frame_info *) 0;
fci->frame = addr;
fci->pc = pc;
fci->signal_handler_caller = IN_SIGTRAMP (fci->pc, (char *)NULL);
find_pc_partial_function (pc, &name, (CORE_ADDR *)NULL,(CORE_ADDR *)NULL);
fci->signal_handler_caller = IN_SIGTRAMP (fci->pc, name);
#ifdef INIT_EXTRA_FRAME_INFO
INIT_EXTRA_FRAME_INFO (0, fci);
@ -263,6 +265,7 @@ get_prev_frame_info (next_frame)
FRAME_ADDR address;
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
@ -382,7 +385,9 @@ get_prev_frame_info (next_frame)
(see tm-sparc.h). We want the pc saved in the inferior frame. */
INIT_FRAME_PC(fromleaf, prev);
if (IN_SIGTRAMP (prev->pc, (char *)NULL))
find_pc_partial_function (prev->pc, &name,
(CORE_ADDR *)NULL,(CORE_ADDR *)NULL);
if (IN_SIGTRAMP (prev->pc, name))
prev->signal_handler_caller = 1;
return prev;
@ -578,18 +583,23 @@ clear_pc_function_cache()
cache_pc_function_name = (char *)0;
}
/* Finds the "function" (text symbol) that is smaller than PC
but greatest of all of the potential text symbols. Sets
*NAME and/or *ADDRESS conditionally if that pointer is non-zero.
Returns 0 if it couldn't find anything, 1 if it did. On a zero
return, *NAME and *ADDRESS are always set to zero. On a 1 return,
*NAME and *ADDRESS contain real information. */
/* Finds the "function" (text symbol) that is smaller than PC but
greatest of all of the potential text symbols. 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_partial_function (pc, name, address)
find_pc_partial_function (pc, name, address, endaddr)
CORE_ADDR pc;
char **name;
CORE_ADDR *address;
CORE_ADDR *endaddr;
{
struct partial_symtab *pst;
struct symbol *f;
@ -597,54 +607,51 @@ find_pc_partial_function (pc, name, address)
struct partial_symbol *psb;
if (pc >= cache_pc_function_low && pc < cache_pc_function_high)
{
if (address)
*address = cache_pc_function_low;
if (name)
*name = cache_pc_function_name;
return 1;
}
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 (IN_SIGTRAMP (pc, (char *)NULL))
{
cache_pc_function_low = SIGTRAMP_START;
cache_pc_function_high = SIGTRAMP_END;
cache_pc_function_name = "<sigtramp>";
goto return_cached_value;
}
#endif
msymbol = lookup_minimal_symbol_by_pc (pc);
pst = find_pc_psymtab (pc);
if (pst)
{
/* Need to read the symbols to get a good value for the end address. */
if (endaddr != NULL && !pst->readin)
PSYMTAB_TO_SYMTAB (pst);
if (pst->readin)
{
/* The information we want has already been read in.
We can go to the already readin symbols and we'll get
the best possible answer. */
/* Checking whether the msymbol has a larger value is for the
"pathological" case mentioned in print_frame_info. */
f = find_pc_function (pc);
if (!f)
if (f != NULL
&& (msymbol == NULL
|| (BLOCK_START (SYMBOL_BLOCK_VALUE (f))
>= SYMBOL_VALUE_ADDRESS (msymbol))))
{
return_error:
/* No available symbol. */
if (name != 0)
*name = 0;
if (address != 0)
*address = 0;
return 0;
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);
goto return_cached_value;
}
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);
if (name)
*name = cache_pc_function_name;
if (address)
*address = cache_pc_function_low;
return 1;
}
/* Get the information from a combination of the pst
(static symbols), and the minimal symbol table (extern
symbols). */
msymbol = lookup_minimal_symbol_by_pc (pc);
/* 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_psymbol (pst, pc);
if (!psb && (msymbol == NULL))
{
goto return_error;
}
if (psb
&& (msymbol == NULL ||
(SYMBOL_VALUE_ADDRESS (psb) >= SYMBOL_VALUE_ADDRESS (msymbol))))
@ -654,35 +661,66 @@ find_pc_partial_function (pc, name, address)
*address = SYMBOL_VALUE_ADDRESS (psb);
if (name)
*name = SYMBOL_NAME (psb);
/* endaddr non-NULL can't happen here. */
return 1;
}
}
else
/* Must be in the minimal symbol table. */
/* Must be in the minimal symbol table. */
if (msymbol == NULL)
{
msymbol = lookup_minimal_symbol_by_pc (pc);
if (msymbol == NULL)
goto return_error;
/* No available symbol. */
if (name != NULL)
*name = 0;
if (address != NULL)
*address = 0;
if (endaddr != NULL)
*endaddr = 0;
return 0;
}
{
if (msymbol -> type == mst_text)
cache_pc_function_low = SYMBOL_VALUE_ADDRESS (msymbol);
else
/* It is a transfer table for Sun shared libraries. */
cache_pc_function_low = pc - FUNCTION_START_OFFSET;
}
/* I believe the purpose of this check is to make sure that anything
beyond the end of the text segment does not appear as part of the
last function of the text segment. It assumes that there is something
other than a mst_text symbol after the text segment. It is broken in
various cases, so anything relying on this behavior (there might be
some places) should be using find_pc_section or some such instead. */
if (msymbol -> type == mst_text)
cache_pc_function_low = SYMBOL_VALUE_ADDRESS (msymbol);
else
/* It is a transfer table for Sun shared libraries. */
cache_pc_function_low = pc - FUNCTION_START_OFFSET;
cache_pc_function_name = SYMBOL_NAME (msymbol);
/* FIXME: Deal with bumping into end of minimal symbols for a given
objfile, and what about testing for mst_text again? */
if (SYMBOL_NAME (msymbol + 1) != NULL)
/* This might be part of a different segment, which might be a bad
idea. Perhaps we should be using the smaller of this address or the
endaddr from find_pc_section. */
cache_pc_function_high = SYMBOL_VALUE_ADDRESS (msymbol + 1);
else
cache_pc_function_high = cache_pc_function_low + 1;
{
/* We got the start address from the last msymbol in the objfile.
So the end address is the end of the section. */
struct obj_section *sec;
sec = find_pc_section (pc);
if (sec == NULL)
{
/* Don't know if this can happen but if it does, then just say
that the function is 1 byte long. */
cache_pc_function_high = cache_pc_function_low + 1;
}
else
cache_pc_function_high = sec->endaddr;
}
return_cached_value:
if (address)
*address = cache_pc_function_low;
if (name)
*name = cache_pc_function_name;
if (endaddr)
*endaddr = cache_pc_function_high;
return 1;
}
@ -714,6 +752,35 @@ block_innermost_frame (block)
#endif /* 0 */
#ifdef SIGCONTEXT_PC_OFFSET
/* Get saved user PC for sigtramp from sigcontext for BSD style sigtramp. */
CORE_ADDR
sigtramp_saved_pc (frame)
FRAME frame;
{
CORE_ADDR sigcontext_addr;
char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT];
int ptrbytes = TARGET_PTR_BIT / TARGET_CHAR_BIT;
int sigcontext_offs = (2 * TARGET_INT_BIT) / TARGET_CHAR_BIT;
/* 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 */
void
_initialize_blockframe ()
{

View File

@ -1,81 +1,113 @@
/* Definitions for dealing with stack frames, for GDB, the GNU debugger.
Copyright (C) 1986, 1989 Free Software Foundation, Inc.
Copyright 1986, 1989, 1991, 1992 Free Software Foundation, Inc.
This file is part of GDB.
GDB is free software; you can redistribute it and/or modify
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 1, or (at your option)
any later version.
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
GDB is distributed in the hope that it will be useful,
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 GDB; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
#if !defined (FRAME_H)
#define FRAME_H 1
#include "param.h"
/*
* FRAME is the type of the identifier of a specific stack frame. It
* is a pointer to the frame cache item corresponding to this frame.
* Please note that frame id's are *not* constant over calls to the
* inferior. Use frame addresses, which are.
*
* FRAME_ADDR is the type of the address of a specific frame. I
* cannot imagine a case in which this would not be CORE_ADDR, so
* maybe it's silly to give it it's own type. Life's rough.
*
* FRAME_FP is a macro which converts from a frame identifier into a
* frame_address.
*
* FRAME_INFO_ID is a macro which "converts" from a frame info pointer
* to a frame id. This is here in case I or someone else decides to
* change the FRAME type again.
*
* This file and blockframe.c are the only places which are allowed to
* use the equivalence between FRAME and struct frame_info *. EXCEPTION:
* value.h uses CORE_ADDR instead of FRAME_ADDR because the compiler
* will accept that in the absense of this file.
*/
/* A FRAME identifies a specific stack frame. It is not constant over
calls to the inferior (frame addresses are, see below).
This is implemented as a "struct frame_info *". This file and
blockframe.c are the only places which are allowed to use the
equivalence between FRAME and struct frame_info *. Exception:
Prototypes in other files use "struct frame_info *" because this
file might not be included.
The distinction between a FRAME and a "struct frame_info *" is made
with the idea of maybe someday changing a FRAME to be something else,
but seems to me that a "struct frame_info *" is fully general (since
any necessarily fields can be added; changing the meaning of existing
fields is not helped by the FRAME distinction), and this distinction
merely creates unnecessary hair. -kingdon, 18 May 93. */
typedef struct frame_info *FRAME;
typedef CORE_ADDR FRAME_ADDR;
#define FRAME_FP(fr) ((fr)->frame)
/* Convert from a "struct frame_info *" into a FRAME. */
#define FRAME_INFO_ID(f) (f)
/*
* Caching structure for stack frames. This is also the structure
* used for extended info about stack frames. May add more to this
* structure as it becomes necessary.
*
* Note that the first entry in the cache will always refer to the
* innermost executing frame. This value should be set (is it?
* Check) in something like normal_stop.
*/
/* Convert from a FRAME into a "struct frame_info *". */
extern struct frame_info *
get_frame_info PARAMS ((FRAME));
/* Type of the address of a frame. It is widely assumed (at least in
prototypes in headers which might not include this header) that
this is the same as CORE_ADDR, and no one can think of a case in
which it wouldn't be, so it might be best to remove this typedef. */
typedef CORE_ADDR FRAME_ADDR;
/* Convert from a FRAME into a frame address. Except in the
machine-dependent *FRAME* macros, a frame address has no defined
meaning other than as a magic cookie which identifies a frame over
calls to the inferior. The only known exception is inferior.h
(PC_IN_CALL_DUMMY) [ON_STACK]; see comments there. You cannot
assume that a frame address contains enough information to
reconstruct the frame; if you want more than just to identify the
frame (e.g. be able to fetch variables relative to that frame),
then save the whole struct frame_info (and the next struct
frame_info, since the latter is used for fetching variables on some
machines). */
#define FRAME_FP(fr) ((fr)->frame)
/* We keep a cache of stack frames, each of which is a "struct
frame_info". The innermost one gets allocated (in
wait_for_inferior) each time the inferior stops; current_frame
points to it. Additional frames get allocated (in
get_prev_frame_info) as needed, and are chained through the next
and prev fields. Any time that the frame cache becomes invalid
(most notably when we execute something, but also if we change how
we interpret the frames (e.g. "set heuristic-fence-post" in
mips-tdep.c, or anything which reads new symbols)), we should call
reinit_frame_cache. */
struct frame_info
{
/* Nominal address of the frame described. */
/* Nominal address of the frame described. See comments at FRAME_FP
about what this means outside the *FRAME* macros; in the *FRAME*
macros, it can mean whatever makes most sense for this machine. */
FRAME_ADDR frame;
/* Address at which execution is occurring in this frame.
For the innermost frame, it's the current pc.
For other frames, it is a pc saved in the next frame. */
CORE_ADDR pc;
/* The frame called by the frame we are describing, or 0.
This may be set even if there isn't a frame called by the one
we are describing (.->next == 0); in that case it is simply the
bottom of this frame */
FRAME_ADDR next_frame;
/* Nonzero if this is a frame associated with calling a signal handler.
Set by machine-dependent code. On some machines, if
the machine-dependent code fails to check for this, the backtrace
will look relatively normal. For example, on the i386
#3 0x158728 in sighold ()
On other machines (e.g. rs6000), the machine-dependent code better
set this to prevent us from trying to print it like a normal frame. */
int signal_handler_caller;
/* Anything extra for this structure that may have been defined
in the machine depedent files. */
#ifdef EXTRA_FRAME_INFO
EXTRA_FRAME_INFO
#endif
/* Pointers to the next and previous frame_info's in this stack. */
/* We should probably also store a "struct frame_saved_regs" here.
This is already done by some machines (e.g. config/m88k/tm-m88k.h)
but there is no reason it couldn't be general. */
/* Pointers to the next and previous frame_info's in the frame cache. */
FRAME next, prev;
};
@ -83,46 +115,142 @@ struct frame_info
struct frame_saved_regs
{
/* For each register, address of where it was saved on entry to the frame,
or zero if it was not saved on entry to this frame. */
/* For each register, address of where it was saved on entry to
the frame, or zero if it was not saved on entry to this frame.
This includes special registers such as pc and fp saved in
special ways in the stack frame. The SP_REGNUM is even more
special, the address here is the sp for the next frame, not the
address where the sp was saved. */
CORE_ADDR regs[NUM_REGS];
};
/* Define 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.
If a particular target needs a different definition, then it can override
the definition here by providing one in the tm file. */
#if !defined (FRAME_CHAIN_VALID)
#if defined (FRAME_CHAIN_VALID_ALTERNATE)
/* 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. */
#define FRAME_CHAIN_VALID(chain, thisframe) \
((chain) != 0 \
&& !inside_main_func ((thisframe) -> pc) \
&& !inside_entry_func ((thisframe) -> pc))
#else
#define FRAME_CHAIN_VALID(chain, thisframe) \
((chain) != 0 \
&& !inside_entry_file (FRAME_SAVED_PC (thisframe)))
#endif /* FRAME_CHAIN_VALID_ALTERNATE */
#endif /* FRAME_CHAIN_VALID */
/* If we encounter a request to use base register addressing of variables
on a machine for which gdb has not been configured to support such
access, report the failure to support this access mode. */
#if !defined (FRAME_GET_BASEREG_VALUE)
#define FRAME_GET_BASEREG_VALUE(frame, regno) \
(error ("Missing valid method for finding contents of base register."),0)
#endif
/* The stack frame that the user has specified for commands to act on.
Note that one cannot assume this is the address of valid data. */
extern FRAME selected_frame;
extern struct frame_info *get_frame_info ();
extern struct frame_info *get_prev_frame_info ();
/* Level of the selected frame:
0 for innermost, 1 for its caller, ...
or -1 for frame specified by address with no defined level. */
extern FRAME create_new_frame ();
extern void flush_cached_frames ();
extern int selected_frame_level;
extern void get_frame_saved_regs ();
extern struct frame_info *
get_prev_frame_info PARAMS ((FRAME));
extern void set_current_frame ();
extern FRAME get_prev_frame ();
extern FRAME get_current_frame ();
extern FRAME get_next_frame ();
extern FRAME
create_new_frame PARAMS ((FRAME_ADDR, CORE_ADDR));
extern struct block *get_frame_block ();
extern struct block *get_current_block ();
extern struct block *get_selected_block ();
extern struct symbol *get_frame_function ();
extern CORE_ADDR get_frame_pc ();
extern CORE_ADDR get_pc_function_start ();
struct block *block_for_pc ();
extern void
flush_cached_frames PARAMS ((void));
int frameless_look_for_prologue ();
extern void
reinit_frame_cache PARAMS ((void));
void print_frame_args ();
extern void
get_frame_saved_regs PARAMS ((struct frame_info *, struct frame_saved_regs *));
/* In stack.c */
extern FRAME find_relative_frame ();
extern void print_selected_frame ();
extern void print_sel_frame ();
extern void select_frame ();
extern void record_selected_frame ();
extern void
set_current_frame PARAMS ((FRAME));
#endif /* frame.h not already included. */
extern FRAME
get_prev_frame PARAMS ((FRAME));
extern FRAME
get_current_frame PARAMS ((void));
extern FRAME
get_next_frame PARAMS ((FRAME));
extern struct block *
get_frame_block PARAMS ((FRAME));
extern struct block *
get_current_block PARAMS ((void));
extern struct block *
get_selected_block PARAMS ((void));
extern struct symbol *
get_frame_function PARAMS ((FRAME));
extern CORE_ADDR
get_frame_pc PARAMS ((FRAME));
extern CORE_ADDR
get_pc_function_start PARAMS ((CORE_ADDR));
extern struct block *
block_for_pc PARAMS ((CORE_ADDR));
extern int
frameless_look_for_prologue PARAMS ((FRAME));
extern void
print_frame_args PARAMS ((struct symbol *, struct frame_info *, int, FILE *));
extern FRAME
find_relative_frame PARAMS ((FRAME, int*));
extern void
print_stack_frame PARAMS ((FRAME, int, int));
extern void
select_frame PARAMS ((FRAME, int));
extern void
record_selected_frame PARAMS ((FRAME_ADDR *, int *));
extern void
print_frame_info PARAMS ((struct frame_info *, int, int, int));
extern CORE_ADDR
find_saved_register PARAMS ((FRAME, int));
extern CORE_ADDR
sigtramp_saved_pc PARAMS ((FRAME));
#endif /* !defined (FRAME_H) */