2002-11-08 Andrew Cagney <ac131313@redhat.com>

* Makefile.in (frame.o): Update dependencies.
	* blockframe.c (current_frame, frame_obstack_alloc)
	(frame_saved_regs_zalloc, get_current_frame)
	(set_current_frame, create_new_frame)
	(set_unwind_by_pc, get_next_frame)
	(flush_cached_frames, reinit_frame_cache)
	(frame_saved_regs_register_unwind)
	(deprecated_generic_get_saved_register)
	(get_prev_frame, get_frame_pc, get_frame_saved_regs)
	(_initialize_blockframe): Move frame code from
	here...
	* frame.c: ...to here.  Include "gdb_obstack.h", "gdbcore.h",
	"annotate.h" and "dummy-frame.h".
	(_initialize_frame): New function.
This commit is contained in:
Andrew Cagney 2002-11-08 20:48:55 +00:00
parent e78c0063c1
commit 4c1e7e9d5e
4 changed files with 563 additions and 552 deletions

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@ -1,3 +1,19 @@
2002-11-08 Andrew Cagney <ac131313@redhat.com>
* Makefile.in (frame.o): Update dependencies.
* blockframe.c (current_frame, frame_obstack_alloc)
(frame_saved_regs_zalloc, get_current_frame)
(set_current_frame, create_new_frame)
(set_unwind_by_pc, get_next_frame)
(flush_cached_frames, reinit_frame_cache)
(frame_saved_regs_register_unwind)
(deprecated_generic_get_saved_register)
(get_prev_frame, get_frame_pc, get_frame_saved_regs)
(_initialize_blockframe): Move frame code from here...
* frame.c: ...to here. Include "gdb_obstack.h", "gdbcore.h",
"annotate.h" and "dummy-frame.h".
(_initialize_frame): New function.
2002-11-08 Jim Blandy <jimb@redhat.com>
* dwarf2read.c (read_func_scope): Restore list_in_scope properly

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@ -1681,7 +1681,8 @@ fork-child.o: fork-child.c $(defs_h) $(gdb_string_h) $(frame_h) \
$(terminal_h) $(gdbthread_h) $(command_h)
# OBSOLETE fr30-tdep.o: fr30-tdep.c
frame.o: frame.c $(defs_h) $(frame_h) $(target_h) $(value_h) $(inferior_h) \
$(regcache_h) $(gdb_assert_h)
$(regcache_h) $(gdb_assert_h) $(gdb_obstack_h) $(dummy_frame_h) \
$(gdbcore_h) $(annotate_h)
frv-tdep.o: frv-tdep.c $(defs_h) $(inferior_h) $(symfile_h) $(gdbcore_h) \
$(arch_utils_h) $(regcache_h)
gcore.o: gcore.c $(defs_h) $(cli_decode_h) $(inferior_h) $(gdbcore_h) \

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@ -39,16 +39,6 @@
/* Prototypes for exported functions. */
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
@ -174,140 +164,6 @@ inside_entry_func (CORE_ADDR 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. */
@ -339,188 +195,6 @@ frameless_look_for_prologue (struct frame_info *frame)
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;
}
/* return the address of the PC for the given FRAME, ie the current PC value
if FRAME is the innermost frame, or the address adjusted to point to the
call instruction if not. */
@ -542,34 +216,6 @@ frame_address_in_block (struct frame_info *frame)
return 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.
@ -1128,200 +774,3 @@ generic_func_frame_chain_valid (CORE_ADDR fp, struct frame_info *fi)
&& !inside_entry_func ((fi)->pc));
}
/* 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);
/* If we're using generic dummy frames, we'd better not be in a call
dummy. (generic_call_dummy_register_unwind ought to have been called
instead.) */
gdb_assert (!(USE_GENERIC_DUMMY_FRAMES
&& 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
deprecated_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)
/* FIXME: cagney/2002-06-26: This should be via the
gdbarch_register_read() method so that it, on the fly,
constructs either a raw or pseudo register from the raw
register cache. */
regcache_raw_read (generic_find_dummy_frame (frame->pc,
frame->frame),
regnum, raw_buffer);
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)
deprecated_read_register_gen (regnum, raw_buffer);
}
void
_initialize_blockframe (void)
{
obstack_init (&frame_cache_obstack);
}

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@ -29,6 +29,10 @@
#include "gdb_assert.h"
#include "gdb_string.h"
#include "builtin-regs.h"
#include "gdb_obstack.h"
#include "dummy-frame.h"
#include "gdbcore.h"
#include "annotate.h"
/* Return a frame uniq ID that can be used to, later re-find the
frame. */
@ -378,3 +382,544 @@ frame_map_regnum_to_name (int regnum)
return REGISTER_NAME (regnum);
return builtin_reg_map_regnum_to_name (regnum);
}
/* 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;
}
/* 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);
/* If we're using generic dummy frames, we'd better not be in a call
dummy. (generic_call_dummy_register_unwind ought to have been called
instead.) */
gdb_assert (!(USE_GENERIC_DUMMY_FRAMES
&& 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
deprecated_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)
/* FIXME: cagney/2002-06-26: This should be via the
gdbarch_register_read() method so that it, on the fly,
constructs either a raw or pseudo register from the raw
register cache. */
regcache_raw_read (generic_find_dummy_frame (frame->pc,
frame->frame),
regnum, raw_buffer);
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)
deprecated_read_register_gen (regnum, raw_buffer);
}
/* 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 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
void
_initialize_frame (void)
{
obstack_init (&frame_cache_obstack);
}