/* Code dealing with dummy stack frames, for GDB, the GNU debugger.
- Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
- 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free
- Software Foundation, Inc.
+ Copyright (C) 1986-2004, 2007-2012 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
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
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. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "frame-unwind.h"
#include "command.h"
#include "gdbcmd.h"
-
-static int pc_in_dummy_frame (CORE_ADDR pc);
+#include "gdb_string.h"
+#include "observer.h"
+#include "gdbthread.h"
/* Dummy frame. This saves the processor state just prior to setting
up the inferior function call. Older targets save the registers
struct dummy_frame
{
struct dummy_frame *next;
-
- /* These values belong to the caller (the previous frame, the frame
- that this unwinds back to). */
- CORE_ADDR pc;
- CORE_ADDR top;
+ /* This frame's ID. Must match the value returned by
+ gdbarch_dummy_id. */
struct frame_id id;
- struct regcache *regcache;
-
- /* 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;
+ /* The caller's state prior to the call. */
+ struct infcall_suspend_state *caller_state;
};
static struct dummy_frame *dummy_frame_stack = NULL;
-/* Function: pc_in_call_dummy (pc)
-
- 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
-deprecated_pc_in_call_dummy (CORE_ADDR pc)
-{
- return pc_in_dummy_frame (pc);
-}
+/* Function: deprecated_pc_in_call_dummy (pc)
-/* Return non-zero if the PC falls in a dummy frame.
-
- The code below which allows DECR_PC_AFTER_BREAK is for infrun.c,
- which may give the function a PC without that subtracted out.
+ Return non-zero if the PC falls in a dummy frame created by gdb for
+ an inferior call. The code below which allows gdbarch_decr_pc_after_break
+ is for infrun.c, which may give the function a PC without that
+ subtracted out.
FIXME: cagney/2002-11-23: This is silly. Surely "infrun.c" can
figure out what the real PC (as in the resume address) is BEFORE
- calling this function. */
+ calling this function.
-static int
-pc_in_dummy_frame (CORE_ADDR pc)
+ NOTE: cagney/2004-08-02: I'm pretty sure that, with the introduction of
+ infrun.c:adjust_pc_after_break (thanks), this function is now
+ always called with a correctly adjusted PC!
+
+ NOTE: cagney/2004-08-02: Code should not need to call this. */
+
+int
+deprecated_pc_in_call_dummy (struct gdbarch *gdbarch, CORE_ADDR pc)
{
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))
+ if ((pc >= dummyframe->id.code_addr)
+ && (pc <= dummyframe->id.code_addr
+ + gdbarch_decr_pc_after_break (gdbarch)))
return 1;
}
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. */
+/* Push the caller's state, along with the dummy frame info, onto the
+ dummy-frame stack. */
void
-generic_push_dummy_frame (void)
+dummy_frame_push (struct infcall_suspend_state *caller_state,
+ const struct frame_id *dummy_id)
{
struct dummy_frame *dummy_frame;
- CORE_ADDR fp = get_frame_base (get_current_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 (gdbarch_inner_than (current_gdbarch, dummy_frame->top, fp))
- /* stale -- destroy! */
- {
- dummy_frame_stack = dummy_frame->next;
- regcache_xfree (dummy_frame->regcache);
- xfree (dummy_frame);
- dummy_frame = dummy_frame_stack;
- }
- else
- dummy_frame = dummy_frame->next;
-
- dummy_frame = xmalloc (sizeof (struct dummy_frame));
- dummy_frame->regcache = frame_save_as_regcache (get_current_frame ());
-
- dummy_frame->pc = read_pc ();
- dummy_frame->top = 0;
- dummy_frame->id = get_frame_id (get_current_frame ());
+
+ dummy_frame = XZALLOC (struct dummy_frame);
+ dummy_frame->caller_state = caller_state;
+ dummy_frame->id = (*dummy_id);
dummy_frame->next = dummy_frame_stack;
dummy_frame_stack = dummy_frame;
}
+/* Remove *DUMMY_PTR from the dummy frame stack. */
+
+static void
+remove_dummy_frame (struct dummy_frame **dummy_ptr)
+{
+ struct dummy_frame *dummy = *dummy_ptr;
+
+ *dummy_ptr = dummy->next;
+ discard_infcall_suspend_state (dummy->caller_state);
+ xfree (dummy);
+}
+
+/* Delete any breakpoint B which is a momentary breakpoint for return from
+ inferior call matching DUMMY_VOIDP. */
+
+static int
+pop_dummy_frame_bpt (struct breakpoint *b, void *dummy_voidp)
+{
+ struct dummy_frame *dummy = dummy_voidp;
+
+ if (b->thread == pid_to_thread_id (inferior_ptid)
+ && b->disposition == disp_del && frame_id_eq (b->frame_id, dummy->id))
+ {
+ while (b->related_breakpoint != b)
+ delete_breakpoint (b->related_breakpoint);
+
+ delete_breakpoint (b);
+
+ /* Stop the traversal. */
+ return 1;
+ }
+
+ /* Continue the traversal. */
+ return 0;
+}
+
+/* Pop *DUMMY_PTR, restoring program state to that before the
+ frame was created. */
+
+static void
+pop_dummy_frame (struct dummy_frame **dummy_ptr)
+{
+ struct dummy_frame *dummy = *dummy_ptr;
+
+ restore_infcall_suspend_state (dummy->caller_state);
+
+ iterate_over_breakpoints (pop_dummy_frame_bpt, dummy);
+
+ /* restore_infcall_control_state frees inf_state,
+ all that remains is to pop *dummy_ptr. */
+ *dummy_ptr = dummy->next;
+ xfree (dummy);
+
+ /* We've made right mess of GDB's local state, just discard
+ everything. */
+ reinit_frame_cache ();
+}
+
+/* Look up DUMMY_ID.
+ Return NULL if not found. */
+
+static struct dummy_frame **
+lookup_dummy_frame (struct frame_id dummy_id)
+{
+ struct dummy_frame **dp;
+
+ for (dp = &dummy_frame_stack; *dp != NULL; dp = &(*dp)->next)
+ {
+ if (frame_id_eq ((*dp)->id, dummy_id))
+ return dp;
+ }
+
+ return NULL;
+}
+
+/* Pop the dummy frame DUMMY_ID, restoring program state to that before the
+ frame was created.
+ On return reinit_frame_cache has been called.
+ If the frame isn't found, flag an internal error.
+
+ NOTE: This can only pop the one frame, even if it is in the middle of the
+ stack, because the other frames may be for different threads, and there's
+ currently no way to tell which stack frame is for which thread. */
+
void
-generic_save_dummy_frame_tos (CORE_ADDR sp)
+dummy_frame_pop (struct frame_id dummy_id)
{
- dummy_frame_stack->top = sp;
+ struct dummy_frame **dp;
+
+ dp = lookup_dummy_frame (dummy_id);
+ gdb_assert (dp != NULL);
+
+ pop_dummy_frame (dp);
}
-/* Record the upper/lower bounds on the address of the call dummy. */
+/* Drop dummy frame DUMMY_ID. Do nothing if it is not found. Do not restore
+ its state into inferior, just free its memory. */
void
-generic_save_call_dummy_addr (CORE_ADDR lo, CORE_ADDR hi)
+dummy_frame_discard (struct frame_id dummy_id)
+{
+ struct dummy_frame **dp;
+
+ dp = lookup_dummy_frame (dummy_id);
+ if (dp)
+ remove_dummy_frame (dp);
+}
+
+/* There may be stale dummy frames, perhaps left over from when an uncaught
+ longjmp took us out of a function that was called by the debugger. Clean
+ them up at least once whenever we start a new inferior. */
+
+static void
+cleanup_dummy_frames (struct target_ops *target, int from_tty)
{
- dummy_frame_stack->call_lo = lo;
- dummy_frame_stack->call_hi = hi;
+ while (dummy_frame_stack != NULL)
+ remove_dummy_frame (&dummy_frame_stack);
}
/* Return the dummy frame cache, it contains both the ID, and a
struct regcache *prev_regcache;
};
-int
+static int
dummy_frame_sniffer (const struct frame_unwind *self,
- struct frame_info *next_frame,
+ struct frame_info *this_frame,
void **this_prologue_cache)
{
struct dummy_frame *dummyframe;
entry point, or some random address on the stack. Trying to use
that PC to apply standard frame ID unwind techniques is just
asking for trouble. */
- /* Use an architecture specific method to extract the prev's dummy
- ID from the next frame. Note that this method uses
- frame_register_unwind to obtain the register values needed to
- determine the dummy frame's ID. */
- this_id = gdbarch_unwind_dummy_id (get_frame_arch (next_frame), next_frame);
-
- /* Use that ID to find the corresponding cache entry. */
- for (dummyframe = dummy_frame_stack;
- dummyframe != NULL;
- dummyframe = dummyframe->next)
+
+ /* Don't bother unless there is at least one dummy frame. */
+ if (dummy_frame_stack != NULL)
{
- /* Does the PC fall within the dummy frame's breakpoint
- instruction. If not, discard this one. */
- if (!(this_id.code_addr >= dummyframe->call_lo
- && this_id.code_addr < dummyframe->call_hi))
- continue;
- /* Does the FP match? "infcall.c" explicitly saved the
- top-of-stack before the inferior function call, assume
- unwind_dummy_id() returns that same stack value. */
- if (this_id.stack_addr != dummyframe->top)
- continue;
- /* The FP matches this dummy frame. */
- {
- struct dummy_frame_cache *cache;
- cache = FRAME_OBSTACK_ZALLOC (struct dummy_frame_cache);
- cache->prev_regcache = dummyframe->regcache;
- cache->this_id = this_id;
- (*this_prologue_cache) = cache;
- return 1;
- }
+ /* Use an architecture specific method to extract this frame's
+ dummy ID, assuming it is a dummy frame. */
+ this_id = gdbarch_dummy_id (get_frame_arch (this_frame), this_frame);
+
+ /* Use that ID to find the corresponding cache entry. */
+ for (dummyframe = dummy_frame_stack;
+ dummyframe != NULL;
+ dummyframe = dummyframe->next)
+ {
+ if (frame_id_eq (dummyframe->id, this_id))
+ {
+ struct dummy_frame_cache *cache;
+
+ cache = FRAME_OBSTACK_ZALLOC (struct dummy_frame_cache);
+ cache->prev_regcache = get_infcall_suspend_state_regcache
+ (dummyframe->caller_state);
+ cache->this_id = this_id;
+ (*this_prologue_cache) = cache;
+ return 1;
+ }
+ }
}
return 0;
}
/* 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
-dummy_frame_prev_register (struct frame_info *next_frame,
+static struct value *
+dummy_frame_prev_register (struct frame_info *this_frame,
void **this_prologue_cache,
- int regnum, int *optimized,
- enum lval_type *lvalp, CORE_ADDR *addrp,
- int *realnum, void *bufferp)
+ int regnum)
{
- /* The dummy-frame sniffer always fills in the cache. */
struct dummy_frame_cache *cache = (*this_prologue_cache);
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ struct value *reg_val;
+
+ /* The dummy-frame sniffer always fills in the cache. */
gdb_assert (cache != NULL);
/* 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)
- {
- /* Return the actual value. */
- /* Use the regcache_cooked_read() method so that it, on the fly,
- constructs either a raw or pseudo register from the raw
- register cache. */
- regcache_cooked_read (cache->prev_regcache, regnum, bufferp);
- }
+ reg_val = value_zero (register_type (gdbarch, regnum), not_lval);
+
+ /* Use the regcache_cooked_read() method so that it, on the fly,
+ constructs either a raw or pseudo register from the raw
+ register cache. */
+ regcache_cooked_read (cache->prev_regcache, regnum,
+ value_contents_writeable (reg_val));
+ return reg_val;
}
-/* Assuming that THIS frame is a dummy (remember, the NEXT and not
- THIS frame is passed in), return the ID of THIS frame. That ID is
+/* Assuming that THIS_FRAME is a dummy, return its ID. That ID is
determined by examining the NEXT frame's unwound registers using
- the method unwind_dummy_id(). As a side effect, THIS dummy frame's
- dummy cache is located and and saved in THIS_PROLOGUE_CACHE. */
+ the method dummy_id(). As a side effect, THIS dummy frame's
+ dummy cache is located and saved in THIS_PROLOGUE_CACHE. */
static void
-dummy_frame_this_id (struct frame_info *next_frame,
+dummy_frame_this_id (struct frame_info *this_frame,
void **this_prologue_cache,
struct frame_id *this_id)
{
/* The dummy-frame sniffer always fills in the cache. */
struct dummy_frame_cache *cache = (*this_prologue_cache);
+
gdb_assert (cache != NULL);
(*this_id) = cache->this_id;
}
-static const struct frame_unwind dummy_frame_unwinder =
+const struct frame_unwind dummy_frame_unwind =
{
DUMMY_FRAME,
+ default_frame_unwind_stop_reason,
dummy_frame_this_id,
dummy_frame_prev_register,
NULL,
dummy_frame_sniffer,
};
-const struct frame_unwind *const dummy_frame_unwind = {
- &dummy_frame_unwinder
-};
-
static void
fprint_dummy_frames (struct ui_file *file)
{
struct dummy_frame *s;
+
for (s = dummy_frame_stack; s != NULL; s = s->next)
{
gdb_print_host_address (s, file);
fprintf_unfiltered (file, ":");
- fprintf_unfiltered (file, " pc=0x%s", paddr (s->pc));
- fprintf_unfiltered (file, " top=0x%s", paddr (s->top));
fprintf_unfiltered (file, " id=");
fprint_frame_id (file, s->id);
- fprintf_unfiltered (file, " call_lo=0x%s", paddr (s->call_lo));
- fprintf_unfiltered (file, " call_hi=0x%s", paddr (s->call_hi));
fprintf_unfiltered (file, "\n");
}
}
fprint_dummy_frames (gdb_stdout);
else
{
+ struct cleanup *cleanups;
struct ui_file *file = gdb_fopen (args, "w");
+
if (file == NULL)
- perror_with_name ("maintenance print dummy-frames");
+ perror_with_name (_("maintenance print dummy-frames"));
+ cleanups = make_cleanup_ui_file_delete (file);
fprint_dummy_frames (file);
- ui_file_delete (file);
+ do_cleanups (cleanups);
}
}
_initialize_dummy_frame (void)
{
add_cmd ("dummy-frames", class_maintenance, maintenance_print_dummy_frames,
- "Print the contents of the internal dummy-frame stack.",
+ _("Print the contents of the internal dummy-frame stack."),
&maintenanceprintlist);
+ observer_attach_inferior_created (cleanup_dummy_frames);
}
projects / deliverable / binutils-gdb.git / blobdiff