/* Cache and manage frames for GDB, the GNU debugger.
- Copyright (C) 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000,
- 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000, 2001,
+ 2002, 2003, 2004, 2007 Free Software Foundation, Inc.
This file is part of GDB.
comment in "frame.h", there is some fuzz here. Frameless
functions are not strictly inner than (same .stack but
different .code and/or .special address). */
- inner = INNER_THAN (l.stack_addr, r.stack_addr);
+ inner = gdbarch_inner_than (current_gdbarch, l.stack_addr, r.stack_addr);
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog, "{ frame_id_inner (l=");
}
CORE_ADDR
-frame_func_unwind (struct frame_info *fi)
+frame_func_unwind (struct frame_info *fi, enum frame_type this_type)
{
if (!fi->prev_func.p)
{
/* Make certain that this, and not the adjacent, function is
found. */
- CORE_ADDR addr_in_block = frame_unwind_address_in_block (fi);
+ CORE_ADDR addr_in_block = frame_unwind_address_in_block (fi, this_type);
fi->prev_func.p = 1;
fi->prev_func.addr = get_pc_function_start (addr_in_block);
if (frame_debug)
CORE_ADDR
get_frame_func (struct frame_info *fi)
{
- return frame_func_unwind (fi->next);
+ return frame_func_unwind (fi->next, get_frame_type (fi));
}
static int
void
frame_pop (struct frame_info *this_frame)
{
+ struct frame_info *prev_frame;
+ struct regcache *scratch;
+ struct cleanup *cleanups;
+
+ /* Ensure that we have a frame to pop to. */
+ prev_frame = get_prev_frame_1 (this_frame);
+
+ if (!prev_frame)
+ error (_("Cannot pop the initial frame."));
+
/* Make a copy of all the register values unwound from this frame.
Save them in a scratch buffer so that there isn't a race between
trying to extract the old values from the current_regcache while
at the same time writing new values into that same cache. */
- struct regcache *scratch
- = frame_save_as_regcache (get_prev_frame_1 (this_frame));
- struct cleanup *cleanups = make_cleanup_regcache_xfree (scratch);
+ scratch = frame_save_as_regcache (prev_frame);
+ cleanups = make_cleanup_regcache_xfree (scratch);
/* FIXME: cagney/2003-03-16: It should be possible to tell the
target's register cache that it is about to be hit with a burst
/* We've made right mess of GDB's local state, just discard
everything. */
- flush_cached_frames ();
+ reinit_frame_cache ();
}
void
int realnum;
frame_register (frame, regnum, &optimized, &lval, &addr, &realnum, myaddr);
- /* FIXME: cagney/2002-05-15: This test is just bogus.
+ return !optimized;
+}
- It indicates that the target failed to supply a value for a
- register because it was "not available" at this time. Problem
- is, the target still has the register and so get saved_register()
- may be returning a value saved on the stack. */
+int
+get_frame_register_bytes (struct frame_info *frame, int regnum,
+ CORE_ADDR offset, int len, gdb_byte *myaddr)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
- if (register_cached (regnum) < 0)
- return 0; /* register value not available */
+ /* Skip registers wholly inside of OFFSET. */
+ while (offset >= register_size (gdbarch, regnum))
+ {
+ offset -= register_size (gdbarch, regnum);
+ regnum++;
+ }
- return !optimized;
+ /* Copy the data. */
+ while (len > 0)
+ {
+ int curr_len = register_size (gdbarch, regnum) - offset;
+ if (curr_len > len)
+ curr_len = len;
+
+ if (curr_len == register_size (gdbarch, regnum))
+ {
+ if (!frame_register_read (frame, regnum, myaddr))
+ return 0;
+ }
+ else
+ {
+ gdb_byte buf[MAX_REGISTER_SIZE];
+ if (!frame_register_read (frame, regnum, buf))
+ return 0;
+ memcpy (myaddr, buf + offset, curr_len);
+ }
+
+ myaddr += curr_len;
+ len -= curr_len;
+ offset = 0;
+ regnum++;
+ }
+
+ return 1;
}
+void
+put_frame_register_bytes (struct frame_info *frame, int regnum,
+ CORE_ADDR offset, int len, const gdb_byte *myaddr)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+
+ /* Skip registers wholly inside of OFFSET. */
+ while (offset >= register_size (gdbarch, regnum))
+ {
+ offset -= register_size (gdbarch, regnum);
+ regnum++;
+ }
+
+ /* Copy the data. */
+ while (len > 0)
+ {
+ int curr_len = register_size (gdbarch, regnum) - offset;
+ if (curr_len > len)
+ curr_len = len;
+
+ if (curr_len == register_size (gdbarch, regnum))
+ {
+ put_frame_register (frame, regnum, myaddr);
+ }
+ else
+ {
+ gdb_byte buf[MAX_REGISTER_SIZE];
+ frame_register_read (frame, regnum, buf);
+ memcpy (buf + offset, myaddr, curr_len);
+ put_frame_register (frame, regnum, buf);
+ }
+
+ myaddr += curr_len;
+ len -= curr_len;
+ offset = 0;
+ regnum++;
+ }
+}
/* Map between a frame register number and its name. A frame register
space is a superset of the cooked register space --- it also
/* The "selected" stack frame is used by default for local and arg
access. May be zero, for no selected frame. */
-struct frame_info *deprecated_selected_frame;
+static struct frame_info *selected_frame;
/* Return the selected frame. Always non-NULL (unless there isn't an
inferior sufficient for creating a frame) in which case an error is
struct frame_info *
get_selected_frame (const char *message)
{
- if (deprecated_selected_frame == NULL)
+ if (selected_frame == NULL)
{
if (message != NULL && (!target_has_registers
|| !target_has_stack
select_frame (get_current_frame ());
}
/* There is always a frame. */
- gdb_assert (deprecated_selected_frame != NULL);
- return deprecated_selected_frame;
+ gdb_assert (selected_frame != NULL);
+ return selected_frame;
}
/* This is a variant of get_selected_frame() which can be called when
{
struct symtab *s;
- deprecated_selected_frame = fi;
+ selected_frame = fi;
/* NOTE: cagney/2002-05-04: FI can be NULL. This occurs when the
frame is being invalidated. */
if (deprecated_selected_frame_level_changed_hook)
void
frame_observer_target_changed (struct target_ops *target)
{
- flush_cached_frames ();
+ reinit_frame_cache ();
}
/* Flush the entire frame cache. */
void
-flush_cached_frames (void)
+reinit_frame_cache (void)
{
+ struct frame_info *fi;
+
+ /* Tear down all frame caches. */
+ for (fi = current_frame; fi != NULL; fi = fi->prev)
+ {
+ if (fi->prologue_cache && fi->unwind->dealloc_cache)
+ fi->unwind->dealloc_cache (fi, fi->prologue_cache);
+ if (fi->base_cache && fi->base->unwind->dealloc_cache)
+ fi->base->unwind->dealloc_cache (fi, fi->base_cache);
+ }
+
/* Since we can't really be sure what the first object allocated was */
obstack_free (&frame_cache_obstack, 0);
obstack_init (&frame_cache_obstack);
select_frame (NULL);
annotate_frames_invalid ();
if (frame_debug)
- fprintf_unfiltered (gdb_stdlog, "{ flush_cached_frames () }\n");
+ fprintf_unfiltered (gdb_stdlog, "{ reinit_frame_cache () }\n");
}
-/* Flush the frame cache, and start a new one if necessary. */
+/* Find where a register is saved (in memory or another register).
+ The result of frame_register_unwind is just where it is saved
+ relative to this particular frame. */
-void
-reinit_frame_cache (void)
+static void
+frame_register_unwind_location (struct frame_info *this_frame, int regnum,
+ int *optimizedp, enum lval_type *lvalp,
+ CORE_ADDR *addrp, int *realnump)
{
- flush_cached_frames ();
+ gdb_assert (this_frame == NULL || this_frame->level >= 0);
- /* FIXME: The inferior_ptid test is wrong if there is a corefile. */
- if (PIDGET (inferior_ptid) != 0)
+ while (this_frame != NULL)
{
- select_frame (get_current_frame ());
+ frame_register_unwind (this_frame, regnum, optimizedp, lvalp,
+ addrp, realnump, NULL);
+
+ if (*optimizedp)
+ break;
+
+ if (*lvalp != lval_register)
+ break;
+
+ regnum = *realnump;
+ this_frame = get_next_frame (this_frame);
}
}
return NULL;
}
+ /* Check that this and the next frame do not unwind the PC register
+ to the same memory location. If they do, then even though they
+ have different frame IDs, the new frame will be bogus; two
+ functions can't share a register save slot for the PC. This can
+ happen when the prologue analyzer finds a stack adjustment, but
+ no PC save.
+
+ This check does assume that the "PC register" is roughly a
+ traditional PC, even if the gdbarch_unwind_pc method adjusts
+ it (we do not rely on the value, only on the unwound PC being
+ dependent on this value). A potential improvement would be
+ to have the frame prev_pc method and the gdbarch unwind_pc
+ method set the same lval and location information as
+ frame_register_unwind. */
+ if (this_frame->level > 0
+ && PC_REGNUM >= 0
+ && get_frame_type (this_frame) == NORMAL_FRAME
+ && get_frame_type (this_frame->next) == NORMAL_FRAME)
+ {
+ int optimized, realnum;
+ enum lval_type lval, nlval;
+ CORE_ADDR addr, naddr;
+
+ frame_register_unwind_location (this_frame, PC_REGNUM, &optimized,
+ &lval, &addr, &realnum);
+ frame_register_unwind_location (get_next_frame (this_frame), PC_REGNUM,
+ &optimized, &nlval, &naddr, &realnum);
+
+ if (lval == lval_memory && lval == nlval && addr == naddr)
+ {
+ if (frame_debug)
+ {
+ fprintf_unfiltered (gdb_stdlog, "-> ");
+ fprint_frame (gdb_stdlog, NULL);
+ fprintf_unfiltered (gdb_stdlog, " // no saved PC }\n");
+ }
+
+ this_frame->stop_reason = UNWIND_NO_SAVED_PC;
+ this_frame->prev = NULL;
+ return NULL;
+ }
+ }
+
/* Allocate the new frame but do not wire it in to the frame chain.
Some (bad) code in INIT_FRAME_EXTRA_INFO tries to look along
frame->next to pull some fancy tricks (of course such code is, by
return frame_pc_unwind (frame->next);
}
-/* Return an address of that falls within the frame's code block. */
+/* Return an address that falls within NEXT_FRAME's caller's code
+ block, assuming that the caller is a THIS_TYPE frame. */
CORE_ADDR
-frame_unwind_address_in_block (struct frame_info *next_frame)
+frame_unwind_address_in_block (struct frame_info *next_frame,
+ enum frame_type this_type)
{
/* A draft address. */
CORE_ADDR pc = frame_pc_unwind (next_frame);
+ /* If NEXT_FRAME was called by a signal frame or dummy frame, then
+ we shold not adjust the unwound PC. These frames may not call
+ their next frame in the normal way; the operating system or GDB
+ may have pushed their resume address manually onto the stack, so
+ it may be the very first instruction. Even if the resume address
+ was not manually pushed, they expect to be returned to. */
+ if (this_type != NORMAL_FRAME)
+ return pc;
+
/* If THIS frame is not inner most (i.e., NEXT isn't the sentinel),
and NEXT is `normal' (i.e., not a sigtramp, dummy, ....) THIS
frame's PC ends up pointing at the instruction fallowing the
"call". Adjust that PC value so that it falls on the call
instruction (which, hopefully, falls within THIS frame's code
- block. So far it's proved to be a very good approximation. See
+ block). So far it's proved to be a very good approximation. See
get_frame_type() for why ->type can't be used. */
if (next_frame->level >= 0
&& get_frame_type (next_frame) == NORMAL_FRAME)
CORE_ADDR
get_frame_address_in_block (struct frame_info *this_frame)
{
- return frame_unwind_address_in_block (this_frame->next);
+ return frame_unwind_address_in_block (this_frame->next,
+ get_frame_type (this_frame));
}
static int
frame inner-most address. */
if (gdbarch_unwind_sp_p (current_gdbarch))
return gdbarch_unwind_sp (current_gdbarch, next_frame);
- /* Things are looking grim. If it's the inner-most frame and there
- is a TARGET_READ_SP, then that can be used. */
- if (next_frame->level < 0 && TARGET_READ_SP_P ())
- return TARGET_READ_SP ();
/* Now things are really are grim. Hope that the value returned by
the SP_REGNUM register is meaningful. */
if (SP_REGNUM >= 0)
case UNWIND_SAME_ID:
return _("previous frame identical to this frame (corrupt stack?)");
+ case UNWIND_NO_SAVED_PC:
+ return _("frame did not save the PC");
+
case UNWIND_NO_REASON:
case UNWIND_FIRST_ERROR:
default:
projects / deliverable / binutils-gdb.git / blobdiff