/* Perform an inferior function call, for GDB, the GNU debugger.
- Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
- 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
- Free Software Foundation, Inc.
+ Copyright (C) 1986-2019 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., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
+#include "infcall.h"
#include "breakpoint.h"
+#include "tracepoint.h"
#include "target.h"
#include "regcache.h"
#include "inferior.h"
-#include "gdb_assert.h"
+#include "infrun.h"
#include "block.h"
#include "gdbcore.h"
#include "language.h"
#include "objfiles.h"
#include "gdbcmd.h"
#include "command.h"
-#include "gdb_string.h"
-#include "infcall.h"
#include "dummy-frame.h"
+#include "ada-lang.h"
+#include "f-lang.h"
+#include "gdbthread.h"
+#include "event-top.h"
+#include "observable.h"
+#include "top.h"
+#include "interps.h"
+#include "thread-fsm.h"
+#include <algorithm>
+#include "gdbsupport/scope-exit.h"
+
+/* If we can't find a function's name from its address,
+ we print this instead. */
+#define RAW_FUNCTION_ADDRESS_FORMAT "at 0x%s"
+#define RAW_FUNCTION_ADDRESS_SIZE (sizeof (RAW_FUNCTION_ADDRESS_FORMAT) \
+ + 2 * sizeof (CORE_ADDR))
/* NOTE: cagney/2003-04-16: What's the future of this code?
asynchronous inferior function call implementation, and that in
turn means restructuring the code so that it is event driven. */
+static bool may_call_functions_p = true;
+static void
+show_may_call_functions_p (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c,
+ const char *value)
+{
+ fprintf_filtered (file,
+ _("Permission to call functions in the program is %s.\n"),
+ value);
+}
+
/* How you should pass arguments to a function depends on whether it
was defined in K&R style or prototype style. If you define a
function using the K&R syntax that takes a `float' argument, then
Unfortunately, on certain older platforms, the debug info doesn't
indicate reliably how each function was defined. A function type's
- TYPE_FLAG_PROTOTYPED flag may be clear, even if the function was
- defined in prototype style. When calling a function whose
- TYPE_FLAG_PROTOTYPED flag is clear, GDB consults this flag to
- decide what to do.
+ TYPE_PROTOTYPED flag may be clear, even if the function was defined
+ in prototype style. When calling a function whose TYPE_PROTOTYPED
+ flag is clear, GDB consults this flag to decide what to do.
For modern targets, it is proper to assume that, if the prototype
flag is clear, that can be trusted: `float' arguments should be
trust the debug information; the user can override this behavior
with "set coerce-float-to-double 0". */
-static int coerce_float_to_double_p = 1;
+static bool coerce_float_to_double_p = true;
static void
show_coerce_float_to_double_p (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
- fprintf_filtered (file, _("\
-Coercion of floats to doubles when calling functions is %s.\n"),
+ fprintf_filtered (file,
+ _("Coercion of floats to doubles "
+ "when calling functions is %s.\n"),
value);
}
the stack and restore the context to what as it was before the
call.
- The default is to stop in the frame where the signal was received. */
+ The default is to stop in the frame where the signal was received. */
-int unwind_on_signal_p = 0;
+static bool unwind_on_signal_p = false;
static void
show_unwind_on_signal_p (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
- fprintf_filtered (file, _("\
-Unwinding of stack if a signal is received while in a call dummy is %s.\n"),
+ fprintf_filtered (file,
+ _("Unwinding of stack if a signal is "
+ "received while in a call dummy is %s.\n"),
value);
}
+/* This boolean tells what gdb should do if a std::terminate call is
+ made while in a function called from gdb (call dummy).
+ As the confines of a single dummy stack prohibit out-of-frame
+ handlers from handling a raised exception, and as out-of-frame
+ handlers are common in C++, this can lead to no handler being found
+ by the unwinder, and a std::terminate call. This is a false positive.
+ If set, gdb unwinds the stack and restores the context to what it
+ was before the call.
+
+ The default is to unwind the frame if a std::terminate call is
+ made. */
+
+static bool unwind_on_terminating_exception_p = true;
+
+static void
+show_unwind_on_terminating_exception_p (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c,
+ const char *value)
+
+{
+ fprintf_filtered (file,
+ _("Unwind stack if a C++ exception is "
+ "unhandled while in a call dummy is %s.\n"),
+ value);
+}
/* Perform the standard coercions that are specified
- for arguments to be passed to C functions.
+ for arguments to be passed to C, Ada or Fortran functions.
If PARAM_TYPE is non-NULL, it is the expected parameter type.
IS_PROTOTYPED is non-zero if the function declaration is prototyped. */
static struct value *
-value_arg_coerce (struct value *arg, struct type *param_type,
- int is_prototyped)
+value_arg_coerce (struct gdbarch *gdbarch, struct value *arg,
+ struct type *param_type, int is_prototyped)
{
+ const struct builtin_type *builtin = builtin_type (gdbarch);
struct type *arg_type = check_typedef (value_type (arg));
struct type *type
= param_type ? check_typedef (param_type) : arg_type;
+ /* Perform any Ada- and Fortran-specific coercion first. */
+ if (current_language->la_language == language_ada)
+ arg = ada_convert_actual (arg, type);
+ else if (current_language->la_language == language_fortran)
+ type = fortran_preserve_arg_pointer (arg, type);
+
+ /* Force the value to the target if we will need its address. At
+ this point, we could allocate arguments on the stack instead of
+ calling malloc if we knew that their addresses would not be
+ saved by the called function. */
+ arg = value_coerce_to_target (arg);
+
switch (TYPE_CODE (type))
{
case TYPE_CODE_REF:
+ case TYPE_CODE_RVALUE_REF:
{
struct value *new_value;
- if (TYPE_CODE (arg_type) == TYPE_CODE_REF)
- return value_cast_pointers (type, arg);
+ if (TYPE_IS_REFERENCE (arg_type))
+ return value_cast_pointers (type, arg, 0);
/* Cast the value to the reference's target type, and then
convert it back to a reference. This will issue an error
if the value was not previously in memory - in some cases
we should clearly be allowing this, but how? */
new_value = value_cast (TYPE_TARGET_TYPE (type), arg);
- new_value = value_ref (new_value);
+ new_value = value_ref (new_value, TYPE_CODE (type));
return new_value;
}
case TYPE_CODE_INT:
/* If we don't have a prototype, coerce to integer type if necessary. */
if (!is_prototyped)
{
- if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
- type = builtin_type_int;
+ if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin->builtin_int))
+ type = builtin->builtin_int;
}
/* Currently all target ABIs require at least the width of an integer
type for an argument. We may have to conditionalize the following
type coercion for future targets. */
- if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
- type = builtin_type_int;
+ if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin->builtin_int))
+ type = builtin->builtin_int;
break;
case TYPE_CODE_FLT:
if (!is_prototyped && coerce_float_to_double_p)
{
- if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_double))
- type = builtin_type_double;
- else if (TYPE_LENGTH (type) > TYPE_LENGTH (builtin_type_double))
- type = builtin_type_long_double;
+ if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin->builtin_double))
+ type = builtin->builtin_double;
+ else if (TYPE_LENGTH (type) > TYPE_LENGTH (builtin->builtin_double))
+ type = builtin->builtin_long_double;
}
break;
case TYPE_CODE_FUNC:
case TYPE_CODE_SET:
case TYPE_CODE_RANGE:
case TYPE_CODE_STRING:
- case TYPE_CODE_BITSTRING:
case TYPE_CODE_ERROR:
case TYPE_CODE_MEMBERPTR:
case TYPE_CODE_METHODPTR:
return value_cast (type, arg);
}
-/* Determine a function's address and its return type from its value.
- Calls error() if the function is not valid for calling. */
+/* See infcall.h. */
CORE_ADDR
-find_function_addr (struct value *function, struct type **retval_type)
+find_function_addr (struct value *function,
+ struct type **retval_type,
+ struct type **function_type)
{
struct type *ftype = check_typedef (value_type (function));
- enum type_code code = TYPE_CODE (ftype);
- struct type *value_type;
- CORE_ADDR funaddr;
+ struct gdbarch *gdbarch = get_type_arch (ftype);
+ struct type *value_type = NULL;
+ /* Initialize it just to avoid a GCC false warning. */
+ CORE_ADDR funaddr = 0;
/* If it's a member function, just look at the function
part of it. */
/* Determine address to call. */
- if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD)
- {
- funaddr = VALUE_ADDRESS (function);
- value_type = TYPE_TARGET_TYPE (ftype);
- }
- else if (code == TYPE_CODE_PTR)
+ if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
+ || TYPE_CODE (ftype) == TYPE_CODE_METHOD)
+ funaddr = value_address (function);
+ else if (TYPE_CODE (ftype) == TYPE_CODE_PTR)
{
funaddr = value_as_address (function);
ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
|| TYPE_CODE (ftype) == TYPE_CODE_METHOD)
+ funaddr = gdbarch_convert_from_func_ptr_addr (gdbarch, funaddr,
+ current_top_target ());
+ }
+ if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
+ || TYPE_CODE (ftype) == TYPE_CODE_METHOD)
+ {
+ if (TYPE_GNU_IFUNC (ftype))
{
- funaddr = gdbarch_convert_from_func_ptr_addr (current_gdbarch,
- funaddr,
- ¤t_target);
- value_type = TYPE_TARGET_TYPE (ftype);
+ CORE_ADDR resolver_addr = funaddr;
+
+ /* Resolve the ifunc. Note this may call the resolver
+ function in the inferior. */
+ funaddr = gnu_ifunc_resolve_addr (gdbarch, resolver_addr);
+
+ /* Skip querying the function symbol if no RETVAL_TYPE or
+ FUNCTION_TYPE have been asked for. */
+ if (retval_type != NULL || function_type != NULL)
+ {
+ type *target_ftype = find_function_type (funaddr);
+ /* If we don't have debug info for the target function,
+ see if we can instead extract the target function's
+ type from the type that the resolver returns. */
+ if (target_ftype == NULL)
+ target_ftype = find_gnu_ifunc_target_type (resolver_addr);
+ if (target_ftype != NULL)
+ {
+ value_type = TYPE_TARGET_TYPE (check_typedef (target_ftype));
+ ftype = target_ftype;
+ }
+ }
}
else
- value_type = builtin_type_int;
+ value_type = TYPE_TARGET_TYPE (ftype);
}
- else if (code == TYPE_CODE_INT)
+ else if (TYPE_CODE (ftype) == TYPE_CODE_INT)
{
/* Handle the case of functions lacking debugging info.
- Their values are characters since their addresses are char */
+ Their values are characters since their addresses are char. */
if (TYPE_LENGTH (ftype) == 1)
funaddr = value_as_address (value_addr (function));
else
- /* Handle integer used as address of a function. */
- funaddr = (CORE_ADDR) value_as_long (function);
+ {
+ /* Handle function descriptors lacking debug info. */
+ int found_descriptor = 0;
- value_type = builtin_type_int;
+ funaddr = 0; /* pacify "gcc -Werror" */
+ if (VALUE_LVAL (function) == lval_memory)
+ {
+ CORE_ADDR nfunaddr;
+
+ funaddr = value_as_address (value_addr (function));
+ nfunaddr = funaddr;
+ funaddr
+ = gdbarch_convert_from_func_ptr_addr (gdbarch, funaddr,
+ current_top_target ());
+ if (funaddr != nfunaddr)
+ found_descriptor = 1;
+ }
+ if (!found_descriptor)
+ /* Handle integer used as address of a function. */
+ funaddr = (CORE_ADDR) value_as_long (function);
+ }
}
else
error (_("Invalid data type for function to be called."));
if (retval_type != NULL)
*retval_type = value_type;
- return funaddr + DEPRECATED_FUNCTION_START_OFFSET;
+ if (function_type != NULL)
+ *function_type = ftype;
+ return funaddr + gdbarch_deprecated_function_start_offset (gdbarch);
}
-/* Call breakpoint_auto_delete on the current contents of the bpstat
- pointed to by arg (which is really a bpstat *). */
+/* For CALL_DUMMY_ON_STACK, push a breakpoint sequence that the called
+ function returns to. */
-static void
-breakpoint_auto_delete_contents (void *arg)
+static CORE_ADDR
+push_dummy_code (struct gdbarch *gdbarch,
+ CORE_ADDR sp, CORE_ADDR funaddr,
+ gdb::array_view<value *> args,
+ struct type *value_type,
+ CORE_ADDR *real_pc, CORE_ADDR *bp_addr,
+ struct regcache *regcache)
{
- breakpoint_auto_delete (*(bpstat *) arg);
+ gdb_assert (gdbarch_push_dummy_code_p (gdbarch));
+
+ return gdbarch_push_dummy_code (gdbarch, sp, funaddr,
+ args.data (), args.size (),
+ value_type, real_pc, bp_addr,
+ regcache);
}
-static CORE_ADDR
-generic_push_dummy_code (struct gdbarch *gdbarch,
- CORE_ADDR sp, CORE_ADDR funaddr, int using_gcc,
- struct value **args, int nargs,
- struct type *value_type,
- CORE_ADDR *real_pc, CORE_ADDR *bp_addr,
- struct regcache *regcache)
+/* See infcall.h. */
+
+void
+error_call_unknown_return_type (const char *func_name)
{
- /* Something here to findout the size of a breakpoint and then
- allocate space for it on the stack. */
- int bplen;
- /* This code assumes frame align. */
- gdb_assert (gdbarch_frame_align_p (gdbarch));
- /* Force the stack's alignment. The intent is to ensure that the SP
- is aligned to at least a breakpoint instruction's boundary. */
- sp = gdbarch_frame_align (gdbarch, sp);
- /* Allocate space for, and then position the breakpoint on the
- stack. */
- if (gdbarch_inner_than (gdbarch, 1, 2))
+ if (func_name != NULL)
+ error (_("'%s' has unknown return type; "
+ "cast the call to its declared return type"),
+ func_name);
+ else
+ error (_("function has unknown return type; "
+ "cast the call to its declared return type"));
+}
+
+/* Fetch the name of the function at FUNADDR.
+ This is used in printing an error message for call_function_by_hand.
+ BUF is used to print FUNADDR in hex if the function name cannot be
+ determined. It must be large enough to hold formatted result of
+ RAW_FUNCTION_ADDRESS_FORMAT. */
+
+static const char *
+get_function_name (CORE_ADDR funaddr, char *buf, int buf_size)
+{
+ {
+ struct symbol *symbol = find_pc_function (funaddr);
+
+ if (symbol)
+ return SYMBOL_PRINT_NAME (symbol);
+ }
+
+ {
+ /* Try the minimal symbols. */
+ struct bound_minimal_symbol msymbol = lookup_minimal_symbol_by_pc (funaddr);
+
+ if (msymbol.minsym)
+ return MSYMBOL_PRINT_NAME (msymbol.minsym);
+ }
+
+ {
+ std::string tmp = string_printf (_(RAW_FUNCTION_ADDRESS_FORMAT),
+ hex_string (funaddr));
+
+ gdb_assert (tmp.length () + 1 <= buf_size);
+ return strcpy (buf, tmp.c_str ());
+ }
+}
+
+/* All the meta data necessary to extract the call's return value. */
+
+struct call_return_meta_info
+{
+ /* The caller frame's architecture. */
+ struct gdbarch *gdbarch;
+
+ /* The called function. */
+ struct value *function;
+
+ /* The return value's type. */
+ struct type *value_type;
+
+ /* Are we returning a value using a structure return or a normal
+ value return? */
+ int struct_return_p;
+
+ /* If using a structure return, this is the structure's address. */
+ CORE_ADDR struct_addr;
+};
+
+/* Extract the called function's return value. */
+
+static struct value *
+get_call_return_value (struct call_return_meta_info *ri)
+{
+ struct value *retval = NULL;
+ thread_info *thr = inferior_thread ();
+ bool stack_temporaries = thread_stack_temporaries_enabled_p (thr);
+
+ if (TYPE_CODE (ri->value_type) == TYPE_CODE_VOID)
+ retval = allocate_value (ri->value_type);
+ else if (ri->struct_return_p)
{
- CORE_ADDR bppc = sp;
- gdbarch_breakpoint_from_pc (gdbarch, &bppc, &bplen);
- sp = gdbarch_frame_align (gdbarch, sp - bplen);
- (*bp_addr) = sp;
- /* Should the breakpoint size/location be re-computed here? */
- }
+ if (stack_temporaries)
+ {
+ retval = value_from_contents_and_address (ri->value_type, NULL,
+ ri->struct_addr);
+ push_thread_stack_temporary (thr, retval);
+ }
+ else
+ {
+ retval = allocate_value (ri->value_type);
+ read_value_memory (retval, 0, 1, ri->struct_addr,
+ value_contents_raw (retval),
+ TYPE_LENGTH (ri->value_type));
+ }
+ }
else
{
- (*bp_addr) = sp;
- gdbarch_breakpoint_from_pc (gdbarch, bp_addr, &bplen);
- sp = gdbarch_frame_align (gdbarch, sp + bplen);
+ retval = allocate_value (ri->value_type);
+ gdbarch_return_value (ri->gdbarch, ri->function, ri->value_type,
+ get_current_regcache (),
+ value_contents_raw (retval), NULL);
+ if (stack_temporaries && class_or_union_p (ri->value_type))
+ {
+ /* Values of class type returned in registers are copied onto
+ the stack and their lval_type set to lval_memory. This is
+ required because further evaluation of the expression
+ could potentially invoke methods on the return value
+ requiring GDB to evaluate the "this" pointer. To evaluate
+ the this pointer, GDB needs the memory address of the
+ value. */
+ value_force_lval (retval, ri->struct_addr);
+ push_thread_stack_temporary (thr, retval);
+ }
}
- /* Inferior resumes at the function entry point. */
- (*real_pc) = funaddr;
- return sp;
+
+ gdb_assert (retval != NULL);
+ return retval;
}
-/* For CALL_DUMMY_ON_STACK, push a breakpoint sequence that the called
- function returns to. */
+/* Data for the FSM that manages an infcall. It's main job is to
+ record the called function's return value. */
-static CORE_ADDR
-push_dummy_code (struct gdbarch *gdbarch,
- CORE_ADDR sp, CORE_ADDR funaddr, int using_gcc,
- struct value **args, int nargs,
- struct type *value_type,
- CORE_ADDR *real_pc, CORE_ADDR *bp_addr,
- struct regcache *regcache)
+struct call_thread_fsm : public thread_fsm
+{
+ /* All the info necessary to be able to extract the return
+ value. */
+ struct call_return_meta_info return_meta_info;
+
+ /* The called function's return value. This is extracted from the
+ target before the dummy frame is popped. */
+ struct value *return_value = nullptr;
+
+ /* The top level that started the infcall (and is synchronously
+ waiting for it to end). */
+ struct ui *waiting_ui;
+
+ call_thread_fsm (struct ui *waiting_ui, struct interp *cmd_interp,
+ struct gdbarch *gdbarch, struct value *function,
+ struct type *value_type,
+ int struct_return_p, CORE_ADDR struct_addr);
+
+ bool should_stop (struct thread_info *thread) override;
+
+ bool should_notify_stop () override;
+};
+
+/* Allocate a new call_thread_fsm object. */
+
+call_thread_fsm::call_thread_fsm (struct ui *waiting_ui,
+ struct interp *cmd_interp,
+ struct gdbarch *gdbarch,
+ struct value *function,
+ struct type *value_type,
+ int struct_return_p, CORE_ADDR struct_addr)
+ : thread_fsm (cmd_interp),
+ waiting_ui (waiting_ui)
+{
+ return_meta_info.gdbarch = gdbarch;
+ return_meta_info.function = function;
+ return_meta_info.value_type = value_type;
+ return_meta_info.struct_return_p = struct_return_p;
+ return_meta_info.struct_addr = struct_addr;
+}
+
+/* Implementation of should_stop method for infcalls. */
+
+bool
+call_thread_fsm::should_stop (struct thread_info *thread)
+{
+ if (stop_stack_dummy == STOP_STACK_DUMMY)
+ {
+ /* Done. */
+ set_finished ();
+
+ /* Stash the return value before the dummy frame is popped and
+ registers are restored to what they were before the
+ call.. */
+ return_value = get_call_return_value (&return_meta_info);
+
+ /* Break out of wait_sync_command_done. */
+ scoped_restore save_ui = make_scoped_restore (¤t_ui, waiting_ui);
+ target_terminal::ours ();
+ waiting_ui->prompt_state = PROMPT_NEEDED;
+ }
+
+ return true;
+}
+
+/* Implementation of should_notify_stop method for infcalls. */
+
+bool
+call_thread_fsm::should_notify_stop ()
+{
+ if (finished_p ())
+ {
+ /* Infcall succeeded. Be silent and proceed with evaluating the
+ expression. */
+ return false;
+ }
+
+ /* Something wrong happened. E.g., an unexpected breakpoint
+ triggered, or a signal was intercepted. Notify the stop. */
+ return true;
+}
+
+/* Subroutine of call_function_by_hand to simplify it.
+ Start up the inferior and wait for it to stop.
+ Return the exception if there's an error, or an exception with
+ reason >= 0 if there's no error.
+
+ This is done inside a TRY_CATCH so the caller needn't worry about
+ thrown errors. The caller should rethrow if there's an error. */
+
+static struct gdb_exception
+run_inferior_call (struct call_thread_fsm *sm,
+ struct thread_info *call_thread, CORE_ADDR real_pc)
{
- if (gdbarch_push_dummy_code_p (gdbarch))
- return gdbarch_push_dummy_code (gdbarch, sp, funaddr, using_gcc,
- args, nargs, value_type, real_pc, bp_addr,
- regcache);
- else
- return generic_push_dummy_code (gdbarch, sp, funaddr, using_gcc,
- args, nargs, value_type, real_pc, bp_addr,
- regcache);
+ struct gdb_exception caught_error;
+ int saved_in_infcall = call_thread->control.in_infcall;
+ ptid_t call_thread_ptid = call_thread->ptid;
+ enum prompt_state saved_prompt_state = current_ui->prompt_state;
+ int was_running = call_thread->state == THREAD_RUNNING;
+ int saved_ui_async = current_ui->async;
+
+ /* Infcalls run synchronously, in the foreground. */
+ current_ui->prompt_state = PROMPT_BLOCKED;
+ /* So that we don't print the prompt prematurely in
+ fetch_inferior_event. */
+ current_ui->async = 0;
+
+ delete_file_handler (current_ui->input_fd);
+
+ call_thread->control.in_infcall = 1;
+
+ clear_proceed_status (0);
+
+ /* Associate the FSM with the thread after clear_proceed_status
+ (otherwise it'd clear this FSM), and before anything throws, so
+ we don't leak it (and any resources it manages). */
+ call_thread->thread_fsm = sm;
+
+ disable_watchpoints_before_interactive_call_start ();
+
+ /* We want to print return value, please... */
+ call_thread->control.proceed_to_finish = 1;
+
+ try
+ {
+ proceed (real_pc, GDB_SIGNAL_0);
+
+ /* Inferior function calls are always synchronous, even if the
+ target supports asynchronous execution. */
+ wait_sync_command_done ();
+ }
+ catch (gdb_exception &e)
+ {
+ caught_error = std::move (e);
+ }
+
+ /* If GDB has the prompt blocked before, then ensure that it remains
+ so. normal_stop calls async_enable_stdin, so reset the prompt
+ state again here. In other cases, stdin will be re-enabled by
+ inferior_event_handler, when an exception is thrown. */
+ current_ui->prompt_state = saved_prompt_state;
+ if (current_ui->prompt_state == PROMPT_BLOCKED)
+ delete_file_handler (current_ui->input_fd);
+ else
+ ui_register_input_event_handler (current_ui);
+ current_ui->async = saved_ui_async;
+
+ /* If the infcall does NOT succeed, normal_stop will have already
+ finished the thread states. However, on success, normal_stop
+ defers here, so that we can set back the thread states to what
+ they were before the call. Note that we must also finish the
+ state of new threads that might have spawned while the call was
+ running. The main cases to handle are:
+
+ - "(gdb) print foo ()", or any other command that evaluates an
+ expression at the prompt. (The thread was marked stopped before.)
+
+ - "(gdb) break foo if return_false()" or similar cases where we
+ do an infcall while handling an event (while the thread is still
+ marked running). In this example, whether the condition
+ evaluates true and thus we'll present a user-visible stop is
+ decided elsewhere. */
+ if (!was_running
+ && call_thread_ptid == inferior_ptid
+ && stop_stack_dummy == STOP_STACK_DUMMY)
+ finish_thread_state (user_visible_resume_ptid (0));
+
+ enable_watchpoints_after_interactive_call_stop ();
+
+ /* Call breakpoint_auto_delete on the current contents of the bpstat
+ of inferior call thread.
+ If all error()s out of proceed ended up calling normal_stop
+ (and perhaps they should; it already does in the special case
+ of error out of resume()), then we wouldn't need this. */
+ if (caught_error.reason < 0)
+ {
+ if (call_thread->state != THREAD_EXITED)
+ breakpoint_auto_delete (call_thread->control.stop_bpstat);
+ }
+
+ call_thread->control.in_infcall = saved_in_infcall;
+
+ return caught_error;
+}
+
+/* See infcall.h. */
+
+struct value *
+call_function_by_hand (struct value *function,
+ type *default_return_type,
+ gdb::array_view<value *> args)
+{
+ return call_function_by_hand_dummy (function, default_return_type,
+ args, NULL, NULL);
}
/* All this stuff with a dummy frame may seem unnecessarily complicated
May fail to return, if a breakpoint or signal is hit
during the execution of the function.
- ARGS is modified to contain coerced values. */
+ ARGS is modified to contain coerced values. */
struct value *
-call_function_by_hand (struct value *function, int nargs, struct value **args)
+call_function_by_hand_dummy (struct value *function,
+ type *default_return_type,
+ gdb::array_view<value *> args,
+ dummy_frame_dtor_ftype *dummy_dtor,
+ void *dummy_dtor_data)
{
CORE_ADDR sp;
- CORE_ADDR dummy_addr;
- struct type *values_type;
- unsigned char struct_return;
+ struct type *target_values_type;
+ function_call_return_method return_method = return_method_normal;
CORE_ADDR struct_addr = 0;
- struct regcache *retbuf;
- struct cleanup *retbuf_cleanup;
- struct inferior_status *inf_status;
- struct cleanup *inf_status_cleanup;
- CORE_ADDR funaddr;
- int using_gcc; /* Set to version of gcc in use, or zero if not gcc */
CORE_ADDR real_pc;
- struct type *ftype = check_typedef (value_type (function));
CORE_ADDR bp_addr;
- struct regcache *caller_regcache;
- struct cleanup *caller_regcache_cleanup;
struct frame_id dummy_id;
+ struct frame_info *frame;
+ struct gdbarch *gdbarch;
+ ptid_t call_thread_ptid;
+ struct gdb_exception e;
+ char name_buf[RAW_FUNCTION_ADDRESS_SIZE];
- if (TYPE_CODE (ftype) == TYPE_CODE_PTR)
- ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
+ if (!may_call_functions_p)
+ error (_("Cannot call functions in the program: "
+ "may-call-functions is off."));
if (!target_has_execution)
noprocess ();
- if (!gdbarch_push_dummy_call_p (current_gdbarch))
- error (_("This target does not support function calls"));
+ if (get_traceframe_number () >= 0)
+ error (_("May not call functions while looking at trace frames."));
+
+ if (execution_direction == EXEC_REVERSE)
+ error (_("Cannot call functions in reverse mode."));
+
+ /* We're going to run the target, and inspect the thread's state
+ afterwards. Hold a strong reference so that the pointer remains
+ valid even if the thread exits. */
+ thread_info_ref call_thread
+ = thread_info_ref::new_reference (inferior_thread ());
- /* Create a cleanup chain that contains the retbuf (buffer
- containing the register values). This chain is create BEFORE the
- inf_status chain so that the inferior status can cleaned up
- (restored or discarded) without having the retbuf freed. */
- retbuf = regcache_xmalloc (current_gdbarch);
- retbuf_cleanup = make_cleanup_regcache_xfree (retbuf);
+ bool stack_temporaries = thread_stack_temporaries_enabled_p (call_thread.get ());
- /* A cleanup for the inferior status. Create this AFTER the retbuf
- so that this can be discarded or applied without interfering with
- the regbuf. */
- inf_status = save_inferior_status (1);
- inf_status_cleanup = make_cleanup_restore_inferior_status (inf_status);
+ frame = get_current_frame ();
+ gdbarch = get_frame_arch (frame);
- /* Save the caller's registers so that they can be restored once the
+ if (!gdbarch_push_dummy_call_p (gdbarch))
+ error (_("This target does not support function calls."));
+
+ /* Find the function type and do a sanity check. */
+ type *ftype;
+ type *values_type;
+ CORE_ADDR funaddr = find_function_addr (function, &values_type, &ftype);
+
+ if (values_type == NULL)
+ values_type = default_return_type;
+ if (values_type == NULL)
+ {
+ const char *name = get_function_name (funaddr,
+ name_buf, sizeof (name_buf));
+ error (_("'%s' has unknown return type; "
+ "cast the call to its declared return type"),
+ name);
+ }
+
+ values_type = check_typedef (values_type);
+
+ if (args.size () < TYPE_NFIELDS (ftype))
+ error (_("Too few arguments in function call."));
+
+ /* A holder for the inferior status.
+ This is only needed while we're preparing the inferior function call. */
+ infcall_control_state_up inf_status (save_infcall_control_state ());
+
+ /* Save the caller's registers and other state associated with the
+ inferior itself so that they can be restored once the
callee returns. To allow nested calls the registers are (further
- down) pushed onto a dummy frame stack. Include a cleanup (which
- is tossed once the regcache has been pushed). */
- caller_regcache = frame_save_as_regcache (get_current_frame ());
- caller_regcache_cleanup = make_cleanup_regcache_xfree (caller_regcache);
+ down) pushed onto a dummy frame stack. This unique pointer
+ is released once the regcache has been pushed). */
+ infcall_suspend_state_up caller_state (save_infcall_suspend_state ());
/* Ensure that the initial SP is correctly aligned. */
{
- CORE_ADDR old_sp = get_frame_sp (get_current_frame ());
- if (gdbarch_frame_align_p (current_gdbarch))
+ CORE_ADDR old_sp = get_frame_sp (frame);
+
+ if (gdbarch_frame_align_p (gdbarch))
{
- sp = gdbarch_frame_align (current_gdbarch, old_sp);
+ sp = gdbarch_frame_align (gdbarch, old_sp);
/* NOTE: cagney/2003-08-13: Skip the "red zone". For some
ABIs, a function can use memory beyond the inner most stack
address. AMD64 called that region the "red zone". Skip at
least the "red zone" size before allocating any space on
the stack. */
- if (gdbarch_inner_than (current_gdbarch, 1, 2))
- sp -= gdbarch_frame_red_zone_size (current_gdbarch);
+ if (gdbarch_inner_than (gdbarch, 1, 2))
+ sp -= gdbarch_frame_red_zone_size (gdbarch);
else
- sp += gdbarch_frame_red_zone_size (current_gdbarch);
+ sp += gdbarch_frame_red_zone_size (gdbarch);
/* Still aligned? */
- gdb_assert (sp == gdbarch_frame_align (current_gdbarch, sp));
+ gdb_assert (sp == gdbarch_frame_align (gdbarch, sp));
/* NOTE: cagney/2002-09-18:
On a RISC architecture, a void parameterless generic dummy
to pay :-). */
if (sp == old_sp)
{
- if (gdbarch_inner_than (current_gdbarch, 1, 2))
+ if (gdbarch_inner_than (gdbarch, 1, 2))
/* Stack grows down. */
- sp = gdbarch_frame_align (current_gdbarch, old_sp - 1);
+ sp = gdbarch_frame_align (gdbarch, old_sp - 1);
else
/* Stack grows up. */
- sp = gdbarch_frame_align (current_gdbarch, old_sp + 1);
+ sp = gdbarch_frame_align (gdbarch, old_sp + 1);
}
- gdb_assert ((gdbarch_inner_than (current_gdbarch, 1, 2)
- && sp <= old_sp)
- || (gdbarch_inner_than (current_gdbarch, 2, 1)
- && sp >= old_sp));
+ /* SP may have underflown address zero here from OLD_SP. Memory access
+ functions will probably fail in such case but that is a target's
+ problem. */
}
else
/* FIXME: cagney/2002-09-18: Hey, you loose!
If the generic dummy frame ends up empty (because nothing is
pushed) GDB won't be able to correctly perform back traces.
If a target is having trouble with backtraces, first thing to
- do is add FRAME_ALIGN() to the architecture vector. If that
- fails, try unwind_dummy_id().
+ do is add FRAME_ALIGN() to the architecture vector. If that
+ fails, try dummy_id().
If the ABI specifies a "Red Zone" (see the doco) the code
below will quietly trash it. */
sp = old_sp;
- }
- funaddr = find_function_addr (function, &values_type);
- CHECK_TYPEDEF (values_type);
+ /* Skip over the stack temporaries that might have been generated during
+ the evaluation of an expression. */
+ if (stack_temporaries)
+ {
+ struct value *lastval;
- {
- struct block *b = block_for_pc (funaddr);
- /* If compiled without -g, assume GCC 2. */
- using_gcc = (b == NULL ? 2 : BLOCK_GCC_COMPILED (b));
+ lastval = get_last_thread_stack_temporary (call_thread.get ());
+ if (lastval != NULL)
+ {
+ CORE_ADDR lastval_addr = value_address (lastval);
+
+ if (gdbarch_inner_than (gdbarch, 1, 2))
+ {
+ gdb_assert (sp >= lastval_addr);
+ sp = lastval_addr;
+ }
+ else
+ {
+ gdb_assert (sp <= lastval_addr);
+ sp = lastval_addr + TYPE_LENGTH (value_type (lastval));
+ }
+
+ if (gdbarch_frame_align_p (gdbarch))
+ sp = gdbarch_frame_align (gdbarch, sp);
+ }
+ }
}
- /* Are we returning a value using a structure return or a normal
- value return? */
+ /* Are we returning a value using a structure return? */
- struct_return = using_struct_return (values_type, using_gcc);
+ if (gdbarch_return_in_first_hidden_param_p (gdbarch, values_type))
+ {
+ return_method = return_method_hidden_param;
+
+ /* Tell the target specific argument pushing routine not to
+ expect a value. */
+ target_values_type = builtin_type (gdbarch)->builtin_void;
+ }
+ else
+ {
+ if (using_struct_return (gdbarch, function, values_type))
+ return_method = return_method_struct;
+ target_values_type = values_type;
+ }
+
+ gdb::observers::inferior_call_pre.notify (inferior_ptid, funaddr);
/* Determine the location of the breakpoint (and possibly other
stuff) that the called function will return to. The SPARC, for a
not just the breakpoint but also an extra word containing the
size (?) of the structure being passed. */
- /* The actual breakpoint (at BP_ADDR) is inserted separatly so there
- is no need to write that out. */
-
- switch (gdbarch_call_dummy_location (current_gdbarch))
+ switch (gdbarch_call_dummy_location (gdbarch))
{
case ON_STACK:
- /* "dummy_addr" is here just to keep old targets happy. New
- targets return that same information via "sp" and "bp_addr". */
- if (gdbarch_inner_than (current_gdbarch, 1, 2))
- {
- sp = push_dummy_code (current_gdbarch, sp, funaddr,
- using_gcc, args, nargs, values_type,
- &real_pc, &bp_addr, get_current_regcache ());
- dummy_addr = sp;
- }
- else
- {
- dummy_addr = sp;
- sp = push_dummy_code (current_gdbarch, sp, funaddr,
- using_gcc, args, nargs, values_type,
- &real_pc, &bp_addr, get_current_regcache ());
- }
+ {
+ const gdb_byte *bp_bytes;
+ CORE_ADDR bp_addr_as_address;
+ int bp_size;
+
+ /* Be careful BP_ADDR is in inferior PC encoding while
+ BP_ADDR_AS_ADDRESS is a plain memory address. */
+
+ sp = push_dummy_code (gdbarch, sp, funaddr, args,
+ target_values_type, &real_pc, &bp_addr,
+ get_current_regcache ());
+
+ /* Write a legitimate instruction at the point where the infcall
+ breakpoint is going to be inserted. While this instruction
+ is never going to be executed, a user investigating the
+ memory from GDB would see this instruction instead of random
+ uninitialized bytes. We chose the breakpoint instruction
+ as it may look as the most logical one to the user and also
+ valgrind 3.7.0 needs it for proper vgdb inferior calls.
+
+ If software breakpoints are unsupported for this target we
+ leave the user visible memory content uninitialized. */
+
+ bp_addr_as_address = bp_addr;
+ bp_bytes = gdbarch_breakpoint_from_pc (gdbarch, &bp_addr_as_address,
+ &bp_size);
+ if (bp_bytes != NULL)
+ write_memory (bp_addr_as_address, bp_bytes, bp_size);
+ }
break;
case AT_ENTRY_POINT:
- real_pc = funaddr;
- dummy_addr = entry_point_address ();
- /* Make certain that the address points at real code, and not a
- function descriptor. */
- dummy_addr = gdbarch_convert_from_func_ptr_addr (current_gdbarch,
- dummy_addr,
- ¤t_target);
- /* A call dummy always consists of just a single breakpoint, so
- it's address is the same as the address of the dummy. */
- bp_addr = dummy_addr;
- break;
- case AT_SYMBOL:
- /* Some executables define a symbol __CALL_DUMMY_ADDRESS whose
- address is the location where the breakpoint should be
- placed. Once all targets are using the overhauled frame code
- this can be deleted - ON_STACK is a better option. */
{
- struct minimal_symbol *sym;
+ CORE_ADDR dummy_addr;
- sym = lookup_minimal_symbol ("__CALL_DUMMY_ADDRESS", NULL, NULL);
real_pc = funaddr;
- if (sym)
- dummy_addr = SYMBOL_VALUE_ADDRESS (sym);
- else
- dummy_addr = entry_point_address ();
- /* Make certain that the address points at real code, and not
- a function descriptor. */
- dummy_addr = gdbarch_convert_from_func_ptr_addr (current_gdbarch,
- dummy_addr,
- ¤t_target);
- /* A call dummy always consists of just a single breakpoint,
- so it's address is the same as the address of the dummy. */
+ dummy_addr = entry_point_address ();
+
+ /* A call dummy always consists of just a single breakpoint, so
+ its address is the same as the address of the dummy.
+
+ The actual breakpoint is inserted separatly so there is no need to
+ write that out. */
bp_addr = dummy_addr;
break;
}
internal_error (__FILE__, __LINE__, _("bad switch"));
}
- if (nargs < TYPE_NFIELDS (ftype))
- error (_("too few arguments in function call"));
-
- {
- int i;
- for (i = nargs - 1; i >= 0; i--)
- {
- int prototyped;
- struct type *param_type;
-
- /* FIXME drow/2002-05-31: Should just always mark methods as
- prototyped. Can we respect TYPE_VARARGS? Probably not. */
- if (TYPE_CODE (ftype) == TYPE_CODE_METHOD)
- prototyped = 1;
- else if (i < TYPE_NFIELDS (ftype))
- prototyped = TYPE_PROTOTYPED (ftype);
- else
- prototyped = 0;
-
- if (i < TYPE_NFIELDS (ftype))
- param_type = TYPE_FIELD_TYPE (ftype, i);
- else
- param_type = NULL;
-
- args[i] = value_arg_coerce (args[i], param_type, prototyped);
-
- /* elz: this code is to handle the case in which the function
- to be called has a pointer to function as parameter and the
- corresponding actual argument is the address of a function
- and not a pointer to function variable. In aCC compiled
- code, the calls through pointers to functions (in the body
- of the function called by hand) are made via
- $$dyncall_external which requires some registers setting,
- this is taken care of if we call via a function pointer
- variable, but not via a function address. In cc this is
- not a problem. */
-
- if (using_gcc == 0)
- {
- if (param_type != NULL && TYPE_CODE (ftype) != TYPE_CODE_METHOD)
- {
- /* if this parameter is a pointer to function. */
- if (TYPE_CODE (param_type) == TYPE_CODE_PTR)
- if (TYPE_CODE (TYPE_TARGET_TYPE (param_type)) == TYPE_CODE_FUNC)
- /* elz: FIXME here should go the test about the
- compiler used to compile the target. We want to
- issue the error message only if the compiler
- used was HP's aCC. If we used HP's cc, then
- there is no problem and no need to return at
- this point. */
- /* Go see if the actual parameter is a variable of
- type pointer to function or just a function. */
- if (VALUE_LVAL (args[i]) == not_lval)
- {
- char *arg_name;
- /* NOTE: cagney/2005-01-02: THIS IS BOGUS. */
- if (find_pc_partial_function ((CORE_ADDR) value_contents (args[i])[0], &arg_name, NULL, NULL))
- error (_("\
-You cannot use function <%s> as argument. \n\
-You must use a pointer to function type variable. Command ignored."), arg_name);
- }
- }
- }
- }
- }
-
- if (gdbarch_deprecated_reg_struct_has_addr_p (current_gdbarch))
+ for (int i = args.size () - 1; i >= 0; i--)
{
- int i;
- /* This is a machine like the sparc, where we may need to pass a
- pointer to the structure, not the structure itself. */
- for (i = nargs - 1; i >= 0; i--)
+ int prototyped;
+ struct type *param_type;
+
+ /* FIXME drow/2002-05-31: Should just always mark methods as
+ prototyped. Can we respect TYPE_VARARGS? Probably not. */
+ if (TYPE_CODE (ftype) == TYPE_CODE_METHOD)
+ prototyped = 1;
+ if (TYPE_TARGET_TYPE (ftype) == NULL && TYPE_NFIELDS (ftype) == 0
+ && default_return_type != NULL)
{
- struct type *arg_type = check_typedef (value_type (args[i]));
- if ((TYPE_CODE (arg_type) == TYPE_CODE_STRUCT
- || TYPE_CODE (arg_type) == TYPE_CODE_UNION
- || TYPE_CODE (arg_type) == TYPE_CODE_ARRAY
- || TYPE_CODE (arg_type) == TYPE_CODE_STRING
- || TYPE_CODE (arg_type) == TYPE_CODE_BITSTRING
- || TYPE_CODE (arg_type) == TYPE_CODE_SET
- || (TYPE_CODE (arg_type) == TYPE_CODE_FLT
- && TYPE_LENGTH (arg_type) > 8)
- )
- && gdbarch_deprecated_reg_struct_has_addr
- (current_gdbarch, using_gcc, arg_type))
- {
- CORE_ADDR addr;
- int len; /* = TYPE_LENGTH (arg_type); */
- int aligned_len;
- arg_type = check_typedef (value_enclosing_type (args[i]));
- len = TYPE_LENGTH (arg_type);
-
- aligned_len = len;
- if (gdbarch_inner_than (current_gdbarch, 1, 2))
- {
- /* stack grows downward */
- sp -= aligned_len;
- /* ... so the address of the thing we push is the
- stack pointer after we push it. */
- addr = sp;
- }
- else
- {
- /* The stack grows up, so the address of the thing
- we push is the stack pointer before we push it. */
- addr = sp;
- sp += aligned_len;
- }
- /* Push the structure. */
- write_memory (addr, value_contents_all (args[i]), len);
- /* The value we're going to pass is the address of the
- thing we just pushed. */
- /*args[i] = value_from_longest (lookup_pointer_type (values_type),
- (LONGEST) addr); */
- args[i] = value_from_pointer (lookup_pointer_type (arg_type),
- addr);
- }
+ /* Calling a no-debug function with the return type
+ explicitly cast. Assume the function is prototyped,
+ with a prototype matching the types of the arguments.
+ E.g., with:
+ float mult (float v1, float v2) { return v1 * v2; }
+ This:
+ (gdb) p (float) mult (2.0f, 3.0f)
+ Is a simpler alternative to:
+ (gdb) p ((float (*) (float, float)) mult) (2.0f, 3.0f)
+ */
+ prototyped = 1;
}
- }
+ else if (i < TYPE_NFIELDS (ftype))
+ prototyped = TYPE_PROTOTYPED (ftype);
+ else
+ prototyped = 0;
+ if (i < TYPE_NFIELDS (ftype))
+ param_type = TYPE_FIELD_TYPE (ftype, i);
+ else
+ param_type = NULL;
+
+ args[i] = value_arg_coerce (gdbarch, args[i],
+ param_type, prototyped);
+
+ if (param_type != NULL && language_pass_by_reference (param_type))
+ args[i] = value_addr (args[i]);
+ }
/* Reserve space for the return structure to be written on the
stack, if necessary. Make certain that the value is correctly
- aligned. */
+ aligned.
+
+ While evaluating expressions, we reserve space on the stack for
+ return values of class type even if the language ABI and the target
+ ABI do not require that the return value be passed as a hidden first
+ argument. This is because we want to store the return value as an
+ on-stack temporary while the expression is being evaluated. This
+ enables us to have chained function calls in expressions.
- if (struct_return)
+ Keeping the return values as on-stack temporaries while the expression
+ is being evaluated is OK because the thread is stopped until the
+ expression is completely evaluated. */
+
+ if (return_method != return_method_normal
+ || (stack_temporaries && class_or_union_p (values_type)))
{
- int len = TYPE_LENGTH (values_type);
- if (gdbarch_inner_than (current_gdbarch, 1, 2))
+ if (gdbarch_inner_than (gdbarch, 1, 2))
{
/* Stack grows downward. Align STRUCT_ADDR and SP after
making space for the return value. */
- sp -= len;
- if (gdbarch_frame_align_p (current_gdbarch))
- sp = gdbarch_frame_align (current_gdbarch, sp);
+ sp -= TYPE_LENGTH (values_type);
+ if (gdbarch_frame_align_p (gdbarch))
+ sp = gdbarch_frame_align (gdbarch, sp);
struct_addr = sp;
}
else
{
/* Stack grows upward. Align the frame, allocate space, and
- then again, re-align the frame??? */
- if (gdbarch_frame_align_p (current_gdbarch))
- sp = gdbarch_frame_align (current_gdbarch, sp);
+ then again, re-align the frame??? */
+ if (gdbarch_frame_align_p (gdbarch))
+ sp = gdbarch_frame_align (gdbarch, sp);
struct_addr = sp;
- sp += len;
- if (gdbarch_frame_align_p (current_gdbarch))
- sp = gdbarch_frame_align (current_gdbarch, sp);
+ sp += TYPE_LENGTH (values_type);
+ if (gdbarch_frame_align_p (gdbarch))
+ sp = gdbarch_frame_align (gdbarch, sp);
}
}
+ std::vector<struct value *> new_args;
+ if (return_method == return_method_hidden_param)
+ {
+ /* Add the new argument to the front of the argument list. */
+ new_args.reserve (args.size ());
+ new_args.push_back
+ (value_from_pointer (lookup_pointer_type (values_type), struct_addr));
+ new_args.insert (new_args.end (), args.begin (), args.end ());
+ args = new_args;
+ }
+
/* Create the dummy stack frame. Pass in the call dummy address as,
presumably, the ABI code knows where, in the call dummy, the
return address should be pointed. */
- sp = gdbarch_push_dummy_call (current_gdbarch, function,
- get_current_regcache (), bp_addr, nargs, args,
- sp, struct_return, struct_addr);
+ sp = gdbarch_push_dummy_call (gdbarch, function, get_current_regcache (),
+ bp_addr, args.size (), args.data (),
+ sp, return_method, struct_addr);
/* Set up a frame ID for the dummy frame so we can pass it to
set_momentary_breakpoint. We need to give the breakpoint a frame
ID so that the breakpoint code can correctly re-identify the
dummy breakpoint. */
/* Sanity. The exact same SP value is returned by PUSH_DUMMY_CALL,
- saved as the dummy-frame TOS, and used by unwind_dummy_id to form
+ saved as the dummy-frame TOS, and used by dummy_id to form
the frame ID's stack address. */
dummy_id = frame_id_build (sp, bp_addr);
inferior. That way it breaks when it returns. */
{
- struct breakpoint *bpt;
- struct symtab_and_line sal;
- init_sal (&sal); /* initialize to zeroes */
+ symtab_and_line sal;
+ sal.pspace = current_program_space;
sal.pc = bp_addr;
sal.section = find_pc_overlay (sal.pc);
+
/* Sanity. The exact same SP value is returned by
PUSH_DUMMY_CALL, saved as the dummy-frame TOS, and used by
- unwind_dummy_id to form the frame ID's stack address. */
- bpt = set_momentary_breakpoint (sal, dummy_id, bp_call_dummy);
+ dummy_id to form the frame ID's stack address. */
+ breakpoint *bpt
+ = set_momentary_breakpoint (gdbarch, sal,
+ dummy_id, bp_call_dummy).release ();
+
+ /* set_momentary_breakpoint invalidates FRAME. */
+ frame = NULL;
+
bpt->disposition = disp_del;
+ gdb_assert (bpt->related_breakpoint == bpt);
+
+ breakpoint *longjmp_b = set_longjmp_breakpoint_for_call_dummy ();
+ if (longjmp_b)
+ {
+ /* Link BPT into the chain of LONGJMP_B. */
+ bpt->related_breakpoint = longjmp_b;
+ while (longjmp_b->related_breakpoint != bpt->related_breakpoint)
+ longjmp_b = longjmp_b->related_breakpoint;
+ longjmp_b->related_breakpoint = bpt;
+ }
}
+ /* Create a breakpoint in std::terminate.
+ If a C++ exception is raised in the dummy-frame, and the
+ exception handler is (normally, and expected to be) out-of-frame,
+ the default C++ handler will (wrongly) be called in an inferior
+ function call. This is wrong, as an exception can be normally
+ and legally handled out-of-frame. The confines of the dummy frame
+ prevent the unwinder from finding the correct handler (or any
+ handler, unless it is in-frame). The default handler calls
+ std::terminate. This will kill the inferior. Assert that
+ terminate should never be called in an inferior function
+ call. Place a momentary breakpoint in the std::terminate function
+ and if triggered in the call, rewind. */
+ if (unwind_on_terminating_exception_p)
+ set_std_terminate_breakpoint ();
+
/* Everything's ready, push all the info needed to restore the
caller (and identify the dummy-frame) onto the dummy-frame
stack. */
- dummy_frame_push (caller_regcache, &dummy_id);
- discard_cleanups (caller_regcache_cleanup);
+ dummy_frame_push (caller_state.release (), &dummy_id, call_thread.get ());
+ if (dummy_dtor != NULL)
+ register_dummy_frame_dtor (dummy_id, call_thread.get (),
+ dummy_dtor, dummy_dtor_data);
+
+ /* Register a clean-up for unwind_on_terminating_exception_breakpoint. */
+ SCOPE_EXIT { delete_std_terminate_breakpoint (); };
/* - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP -
If you're looking to implement asynchronous dummy-frames, then
just below is the place to chop this function in two.. */
- /* Now proceed, having reached the desired place. */
- clear_proceed_status ();
-
- /* Execute a "stack dummy", a piece of code stored in the stack by
- the debugger to be executed in the inferior.
-
- The dummy's frame is automatically popped whenever that break is
- hit. If that is the first time the program stops,
- call_function_by_hand returns to its caller with that frame
- already gone and sets RC to 0.
-
- Otherwise, set RC to a non-zero value. If the called function
- receives a random signal, we do not allow the user to continue
- executing it as this may not work. The dummy frame is poped and
- we return 1. If we hit a breakpoint, we leave the frame in place
- and return 2 (the frame will eventually be popped when we do hit
- the dummy end breakpoint). */
-
{
- struct cleanup *old_cleanups = make_cleanup (null_cleanup, 0);
- int saved_async = 0;
-
- /* If all error()s out of proceed ended up calling normal_stop
- (and perhaps they should; it already does in the special case
- of error out of resume()), then we wouldn't need this. */
- make_cleanup (breakpoint_auto_delete_contents, &stop_bpstat);
-
- disable_watchpoints_before_interactive_call_start ();
- proceed_to_finish = 1; /* We want stop_registers, please... */
-
- if (target_can_async_p ())
- saved_async = target_async_mask (0);
-
- proceed (real_pc, TARGET_SIGNAL_0, 0);
-
- if (saved_async)
- target_async_mask (saved_async);
-
- enable_watchpoints_after_interactive_call_stop ();
-
- discard_cleanups (old_cleanups);
- }
+ struct thread_fsm *saved_sm;
+ struct call_thread_fsm *sm;
- if (stopped_by_random_signal || !stop_stack_dummy)
- {
- /* Find the name of the function we're about to complain about. */
- const char *name = NULL;
+ /* Save the current FSM. We'll override it. */
+ saved_sm = call_thread->thread_fsm;
+ call_thread->thread_fsm = NULL;
+
+ /* Save this thread's ptid, we need it later but the thread
+ may have exited. */
+ call_thread_ptid = call_thread->ptid;
+
+ /* Run the inferior until it stops. */
+
+ /* Create the FSM used to manage the infcall. It tells infrun to
+ not report the stop to the user, and captures the return value
+ before the dummy frame is popped. run_inferior_call registers
+ it with the thread ASAP. */
+ sm = new call_thread_fsm (current_ui, command_interp (),
+ gdbarch, function,
+ values_type,
+ return_method != return_method_normal,
+ struct_addr);
+
+ e = run_inferior_call (sm, call_thread.get (), real_pc);
+
+ gdb::observers::inferior_call_post.notify (call_thread_ptid, funaddr);
+
+ if (call_thread->state != THREAD_EXITED)
{
- struct symbol *symbol = find_pc_function (funaddr);
- if (symbol)
- name = SYMBOL_PRINT_NAME (symbol);
- else
- {
- /* Try the minimal symbols. */
- struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (funaddr);
- if (msymbol)
- name = SYMBOL_PRINT_NAME (msymbol);
- }
- if (name == NULL)
+ /* The FSM should still be the same. */
+ gdb_assert (call_thread->thread_fsm == sm);
+
+ if (call_thread->thread_fsm->finished_p ())
{
- /* Can't use a cleanup here. It is discarded, instead use
- an alloca. */
- char *tmp = xstrprintf ("at %s", hex_string (funaddr));
- char *a = alloca (strlen (tmp) + 1);
- strcpy (a, tmp);
- xfree (tmp);
- name = a;
+ struct value *retval;
+
+ /* The inferior call is successful. Pop the dummy frame,
+ which runs its destructors and restores the inferior's
+ suspend state, and restore the inferior control
+ state. */
+ dummy_frame_pop (dummy_id, call_thread.get ());
+ restore_infcall_control_state (inf_status.release ());
+
+ /* Get the return value. */
+ retval = sm->return_value;
+
+ /* Clean up / destroy the call FSM, and restore the
+ original one. */
+ call_thread->thread_fsm->clean_up (call_thread.get ());
+ delete call_thread->thread_fsm;
+ call_thread->thread_fsm = saved_sm;
+
+ maybe_remove_breakpoints ();
+
+ gdb_assert (retval != NULL);
+ return retval;
}
+
+ /* Didn't complete. Clean up / destroy the call FSM, and restore the
+ previous state machine, and handle the error. */
+ call_thread->thread_fsm->clean_up (call_thread.get ());
+ delete call_thread->thread_fsm;
+ call_thread->thread_fsm = saved_sm;
}
+ }
+
+ /* Rethrow an error if we got one trying to run the inferior. */
+
+ if (e.reason < 0)
+ {
+ const char *name = get_function_name (funaddr,
+ name_buf, sizeof (name_buf));
+
+ discard_infcall_control_state (inf_status.release ());
+
+ /* We could discard the dummy frame here if the program exited,
+ but it will get garbage collected the next time the program is
+ run anyway. */
+
+ switch (e.reason)
+ {
+ case RETURN_ERROR:
+ throw_error (e.error, _("%s\n\
+An error occurred while in a function called from GDB.\n\
+Evaluation of the expression containing the function\n\
+(%s) will be abandoned.\n\
+When the function is done executing, GDB will silently stop."),
+ e.what (), name);
+ case RETURN_QUIT:
+ default:
+ throw_exception (std::move (e));
+ }
+ }
+
+ /* If the program has exited, or we stopped at a different thread,
+ exit and inform the user. */
+
+ if (! target_has_execution)
+ {
+ const char *name = get_function_name (funaddr,
+ name_buf, sizeof (name_buf));
+
+ /* If we try to restore the inferior status,
+ we'll crash as the inferior is no longer running. */
+ discard_infcall_control_state (inf_status.release ());
+
+ /* We could discard the dummy frame here given that the program exited,
+ but it will get garbage collected the next time the program is
+ run anyway. */
+
+ error (_("The program being debugged exited while in a function "
+ "called from GDB.\n"
+ "Evaluation of the expression containing the function\n"
+ "(%s) will be abandoned."),
+ name);
+ }
+
+ if (call_thread_ptid != inferior_ptid)
+ {
+ const char *name = get_function_name (funaddr,
+ name_buf, sizeof (name_buf));
+
+ /* We've switched threads. This can happen if another thread gets a
+ signal or breakpoint while our thread was running.
+ There's no point in restoring the inferior status,
+ we're in a different thread. */
+ discard_infcall_control_state (inf_status.release ());
+ /* Keep the dummy frame record, if the user switches back to the
+ thread with the hand-call, we'll need it. */
+ if (stopped_by_random_signal)
+ error (_("\
+The program received a signal in another thread while\n\
+making a function call from GDB.\n\
+Evaluation of the expression containing the function\n\
+(%s) will be abandoned.\n\
+When the function is done executing, GDB will silently stop."),
+ name);
+ else
+ error (_("\
+The program stopped in another thread while making a function call from GDB.\n\
+Evaluation of the expression containing the function\n\
+(%s) will be abandoned.\n\
+When the function is done executing, GDB will silently stop."),
+ name);
+ }
+
+ {
+ /* Make a copy as NAME may be in an objfile freed by dummy_frame_pop. */
+ std::string name = get_function_name (funaddr, name_buf,
+ sizeof (name_buf));
+
if (stopped_by_random_signal)
{
/* We stopped inside the FUNCTION because of a random
signal. Further execution of the FUNCTION is not
- allowed. */
+ allowed. */
if (unwind_on_signal_p)
{
- /* The user wants the context restored. */
+ /* The user wants the context restored. */
/* We must get back to the frame we were before the
- dummy call. */
- frame_pop (get_current_frame ());
+ dummy call. */
+ dummy_frame_pop (dummy_id, call_thread.get ());
+
+ /* We also need to restore inferior status to that before the
+ dummy call. */
+ restore_infcall_control_state (inf_status.release ());
/* FIXME: Insert a bunch of wrap_here; name can be very
long if it's a C++ name with arguments and stuff. */
error (_("\
The program being debugged was signaled while in a function called from GDB.\n\
GDB has restored the context to what it was before the call.\n\
-To change this behavior use \"set unwindonsignal off\"\n\
-Evaluation of the expression containing the function (%s) will be abandoned."),
- name);
+To change this behavior use \"set unwindonsignal off\".\n\
+Evaluation of the expression containing the function\n\
+(%s) will be abandoned."),
+ name.c_str ());
}
else
{
/* The user wants to stay in the frame where we stopped
- (default).*/
- /* If we restored the inferior status (via the cleanup),
- we would print a spurious error message (Unable to
- restore previously selected frame), would write the
- registers from the inf_status (which is wrong), and
- would do other wrong things. */
- discard_cleanups (inf_status_cleanup);
- discard_inferior_status (inf_status);
+ (default).
+ Discard inferior status, we're not at the same point
+ we started at. */
+ discard_infcall_control_state (inf_status.release ());
+
/* FIXME: Insert a bunch of wrap_here; name can be very
long if it's a C++ name with arguments and stuff. */
error (_("\
The program being debugged was signaled while in a function called from GDB.\n\
GDB remains in the frame where the signal was received.\n\
-To change this behavior use \"set unwindonsignal on\"\n\
-Evaluation of the expression containing the function (%s) will be abandoned."),
- name);
+To change this behavior use \"set unwindonsignal on\".\n\
+Evaluation of the expression containing the function\n\
+(%s) will be abandoned.\n\
+When the function is done executing, GDB will silently stop."),
+ name.c_str ());
}
}
- if (!stop_stack_dummy)
+ if (stop_stack_dummy == STOP_STD_TERMINATE)
+ {
+ /* We must get back to the frame we were before the dummy
+ call. */
+ dummy_frame_pop (dummy_id, call_thread.get ());
+
+ /* We also need to restore inferior status to that before
+ the dummy call. */
+ restore_infcall_control_state (inf_status.release ());
+
+ error (_("\
+The program being debugged entered a std::terminate call, most likely\n\
+caused by an unhandled C++ exception. GDB blocked this call in order\n\
+to prevent the program from being terminated, and has restored the\n\
+context to its original state before the call.\n\
+To change this behaviour use \"set unwind-on-terminating-exception off\".\n\
+Evaluation of the expression containing the function (%s)\n\
+will be abandoned."),
+ name.c_str ());
+ }
+ else if (stop_stack_dummy == STOP_NONE)
{
- /* We hit a breakpoint inside the FUNCTION. */
- /* If we restored the inferior status (via the cleanup), we
- would print a spurious error message (Unable to restore
- previously selected frame), would write the registers
- from the inf_status (which is wrong), and would do other
- wrong things. */
- discard_cleanups (inf_status_cleanup);
- discard_inferior_status (inf_status);
+
+ /* We hit a breakpoint inside the FUNCTION.
+ Keep the dummy frame, the user may want to examine its state.
+ Discard inferior status, we're not at the same point
+ we started at. */
+ discard_infcall_control_state (inf_status.release ());
+
/* The following error message used to say "The expression
which contained the function call has been discarded."
It is a hard concept to explain in a few words. Ideally,
a C++ name with arguments and stuff. */
error (_("\
The program being debugged stopped while in a function called from GDB.\n\
-When the function (%s) is done executing, GDB will silently\n\
-stop (instead of continuing to evaluate the expression containing\n\
-the function call)."), name);
+Evaluation of the expression containing the function\n\
+(%s) will be abandoned.\n\
+When the function is done executing, GDB will silently stop."),
+ name.c_str ());
}
- /* The above code errors out, so ... */
- internal_error (__FILE__, __LINE__, _("... should not be here"));
}
- /* If we get here the called FUNCTION run to completion. */
-
- /* On normal return, the stack dummy has been popped already. */
- regcache_cpy_no_passthrough (retbuf, stop_registers);
-
- /* Restore the inferior status, via its cleanup. At this stage,
- leave the RETBUF alone. */
- do_cleanups (inf_status_cleanup);
-
- /* Figure out the value returned by the function. */
- {
- struct value *retval = NULL;
-
- if (TYPE_CODE (values_type) == TYPE_CODE_VOID)
- {
- /* If the function returns void, don't bother fetching the
- return value. */
- retval = allocate_value (values_type);
- }
- else
- {
- struct gdbarch *arch = current_gdbarch;
-
- switch (gdbarch_return_value (arch, values_type, NULL, NULL, NULL))
- {
- case RETURN_VALUE_REGISTER_CONVENTION:
- case RETURN_VALUE_ABI_RETURNS_ADDRESS:
- case RETURN_VALUE_ABI_PRESERVES_ADDRESS:
- retval = allocate_value (values_type);
- gdbarch_return_value (current_gdbarch, values_type, retbuf,
- value_contents_raw (retval), NULL);
- break;
- case RETURN_VALUE_STRUCT_CONVENTION:
- retval = value_at (values_type, struct_addr);
- break;
- }
- }
-
- do_cleanups (retbuf_cleanup);
-
- gdb_assert(retval);
- return retval;
- }
+ /* The above code errors out, so ... */
+ gdb_assert_not_reached ("... should not be here");
}
-\f
-
-/* Provide a prototype to silence -Wmissing-prototypes. */
-void _initialize_infcall (void);
void
_initialize_infcall (void)
{
+ add_setshow_boolean_cmd ("may-call-functions", no_class,
+ &may_call_functions_p, _("\
+Set permission to call functions in the program."), _("\
+Show permission to call functions in the program."), _("\
+When this permission is on, GDB may call functions in the program.\n\
+Otherwise, any sort of attempt to call a function in the program\n\
+will result in an error."),
+ NULL,
+ show_may_call_functions_p,
+ &setlist, &showlist);
+
add_setshow_boolean_cmd ("coerce-float-to-double", class_obscure,
&coerce_float_to_double_p, _("\
Set coercion of floats to doubles when calling functions."), _("\
-Show coercion of floats to doubles when calling functions"), _("\
+Show coercion of floats to doubles when calling functions."), _("\
Variables of type float should generally be converted to doubles before\n\
calling an unprototyped function, and left alone when calling a prototyped\n\
function. However, some older debug info formats do not provide enough\n\
information to determine that a function is prototyped. If this flag is\n\
set, GDB will perform the conversion for a function it considers\n\
unprototyped.\n\
-The default is to perform the conversion.\n"),
+The default is to perform the conversion."),
NULL,
show_coerce_float_to_double_p,
&setlist, &showlist);
NULL,
show_unwind_on_signal_p,
&setlist, &showlist);
+
+ add_setshow_boolean_cmd ("unwind-on-terminating-exception", no_class,
+ &unwind_on_terminating_exception_p, _("\
+Set unwinding of stack if std::terminate is called while in call dummy."), _("\
+Show unwinding of stack if std::terminate() is called while in a call dummy."),
+ _("\
+The unwind on terminating exception flag lets the user determine\n\
+what gdb should do if a std::terminate() call is made from the\n\
+default exception handler. If set, gdb unwinds the stack and restores\n\
+the context to what it was before the call. If unset, gdb allows the\n\
+std::terminate call to proceed.\n\
+The default is to unwind the frame."),
+ NULL,
+ show_unwind_on_terminating_exception_p,
+ &setlist, &showlist);
+
}
projects / deliverable / binutils-gdb.git / blobdiff