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 = IN_SIGTRAMP (fi->pc, name);
#ifdef INIT_EXTRA_FRAME_INFO
INIT_EXTRA_FRAME_INFO (0, fi);
#endif
return fi;
}
int
legacy_pc_in_sigtramp (CORE_ADDR pc, char *name)
{
return IN_SIGTRAMP(pc, name);
}
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 (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;
}
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);
if (!FRAME_CHAIN_VALID (address, next_frame))
return 0;
address = FRAME_CHAIN_COMBINE (address, next_frame);
}
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;
/* 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. [email protected], 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.
[email protected], 13Apr93, 31Jan94, 14Dec94. */
INIT_FRAME_PC_FIRST (fromleaf, prev);
#ifdef INIT_EXTRA_FRAME_INFO
INIT_EXTRA_FRAME_INFO (fromleaf, prev);
#endif
/* 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;
}
}
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;
}
