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3360bae61f
get_call_return_value can handle RETURN_VALUE_STRUCT_CONVENTION, because the call is completely managed by gdb. However, it does not handle variably-sized types correctly. The simplest way to fix this is to use value_at_non_lval, which does type resolution.
1641 lines
55 KiB
C
1641 lines
55 KiB
C
/* Perform an inferior function call, for GDB, the GNU debugger.
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Copyright (C) 1986-2023 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "defs.h"
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#include "infcall.h"
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#include "breakpoint.h"
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#include "tracepoint.h"
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#include "target.h"
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#include "regcache.h"
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#include "inferior.h"
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#include "infrun.h"
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#include "block.h"
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#include "gdbcore.h"
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#include "language.h"
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#include "objfiles.h"
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#include "gdbcmd.h"
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#include "command.h"
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#include "dummy-frame.h"
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#include "ada-lang.h"
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#include "f-lang.h"
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#include "gdbthread.h"
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#include "event-top.h"
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#include "observable.h"
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#include "top.h"
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#include "interps.h"
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#include "thread-fsm.h"
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#include <algorithm>
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#include "gdbsupport/scope-exit.h"
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#include <list>
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/* True if we are debugging inferior calls. */
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static bool debug_infcall = false;
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/* Print an "infcall" debug statement. */
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#define infcall_debug_printf(fmt, ...) \
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debug_prefixed_printf_cond (debug_infcall, "infcall", fmt, ##__VA_ARGS__)
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/* Print "infcall" enter/exit debug statements. */
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#define INFCALL_SCOPED_DEBUG_ENTER_EXIT \
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scoped_debug_enter_exit (debug_infcall, "infcall")
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/* Print "infcall" start/end debug statements. */
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#define INFCALL_SCOPED_DEBUG_START_END(fmt, ...) \
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scoped_debug_start_end (debug_infrun, "infcall", fmt, ##__VA_ARGS__)
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/* Implement 'show debug infcall'. */
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static void
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show_debug_infcall (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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gdb_printf (file, _("Inferior call debugging is %s.\n"), value);
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}
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/* If we can't find a function's name from its address,
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we print this instead. */
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#define RAW_FUNCTION_ADDRESS_FORMAT "at 0x%s"
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#define RAW_FUNCTION_ADDRESS_SIZE (sizeof (RAW_FUNCTION_ADDRESS_FORMAT) \
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+ 2 * sizeof (CORE_ADDR))
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/* NOTE: cagney/2003-04-16: What's the future of this code?
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GDB needs an asynchronous expression evaluator, that means an
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asynchronous inferior function call implementation, and that in
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turn means restructuring the code so that it is event driven. */
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static bool may_call_functions_p = true;
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static void
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show_may_call_functions_p (struct ui_file *file, int from_tty,
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struct cmd_list_element *c,
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const char *value)
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{
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gdb_printf (file,
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_("Permission to call functions in the program is %s.\n"),
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value);
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}
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/* How you should pass arguments to a function depends on whether it
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was defined in K&R style or prototype style. If you define a
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function using the K&R syntax that takes a `float' argument, then
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callers must pass that argument as a `double'. If you define the
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function using the prototype syntax, then you must pass the
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argument as a `float', with no promotion.
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Unfortunately, on certain older platforms, the debug info doesn't
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indicate reliably how each function was defined. A function type's
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TYPE_PROTOTYPED flag may be clear, even if the function was defined
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in prototype style. When calling a function whose TYPE_PROTOTYPED
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flag is clear, GDB consults this flag to decide what to do.
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For modern targets, it is proper to assume that, if the prototype
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flag is clear, that can be trusted: `float' arguments should be
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promoted to `double'. For some older targets, if the prototype
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flag is clear, that doesn't tell us anything. The default is to
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trust the debug information; the user can override this behavior
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with "set coerce-float-to-double 0". */
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static bool coerce_float_to_double_p = true;
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static void
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show_coerce_float_to_double_p (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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gdb_printf (file,
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_("Coercion of floats to doubles "
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"when calling functions is %s.\n"),
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value);
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}
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/* This boolean tells what gdb should do if a signal is received while
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in a function called from gdb (call dummy). If set, gdb unwinds
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the stack and restore the context to what as it was before the
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call.
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The default is to stop in the frame where the signal was received. */
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static bool unwind_on_signal_p = false;
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static void
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show_unwind_on_signal_p (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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gdb_printf (file,
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_("Unwinding of stack if a signal is "
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"received while in a call dummy is %s.\n"),
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value);
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}
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/* This boolean tells what gdb should do if a std::terminate call is
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made while in a function called from gdb (call dummy).
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As the confines of a single dummy stack prohibit out-of-frame
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handlers from handling a raised exception, and as out-of-frame
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handlers are common in C++, this can lead to no handler being found
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by the unwinder, and a std::terminate call. This is a false positive.
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If set, gdb unwinds the stack and restores the context to what it
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was before the call.
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The default is to unwind the frame if a std::terminate call is
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made. */
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static bool unwind_on_terminating_exception_p = true;
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static void
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show_unwind_on_terminating_exception_p (struct ui_file *file, int from_tty,
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struct cmd_list_element *c,
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const char *value)
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{
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gdb_printf (file,
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_("Unwind stack if a C++ exception is "
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"unhandled while in a call dummy is %s.\n"),
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value);
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}
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/* Perform the standard coercions that are specified
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for arguments to be passed to C, Ada or Fortran functions.
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If PARAM_TYPE is non-NULL, it is the expected parameter type.
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IS_PROTOTYPED is non-zero if the function declaration is prototyped. */
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static struct value *
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value_arg_coerce (struct gdbarch *gdbarch, struct value *arg,
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struct type *param_type, int is_prototyped)
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{
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const struct builtin_type *builtin = builtin_type (gdbarch);
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struct type *arg_type = check_typedef (value_type (arg));
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struct type *type
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= param_type ? check_typedef (param_type) : arg_type;
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/* Perform any Ada- and Fortran-specific coercion first. */
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if (current_language->la_language == language_ada)
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arg = ada_convert_actual (arg, type);
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else if (current_language->la_language == language_fortran)
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type = fortran_preserve_arg_pointer (arg, type);
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/* Force the value to the target if we will need its address. At
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this point, we could allocate arguments on the stack instead of
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calling malloc if we knew that their addresses would not be
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saved by the called function. */
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arg = value_coerce_to_target (arg);
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switch (type->code ())
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{
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case TYPE_CODE_REF:
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case TYPE_CODE_RVALUE_REF:
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{
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struct value *new_value;
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if (TYPE_IS_REFERENCE (arg_type))
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return value_cast_pointers (type, arg, 0);
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/* Cast the value to the reference's target type, and then
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convert it back to a reference. This will issue an error
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if the value was not previously in memory - in some cases
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we should clearly be allowing this, but how? */
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new_value = value_cast (type->target_type (), arg);
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new_value = value_ref (new_value, type->code ());
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return new_value;
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}
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case TYPE_CODE_INT:
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case TYPE_CODE_CHAR:
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case TYPE_CODE_BOOL:
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case TYPE_CODE_ENUM:
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/* If we don't have a prototype, coerce to integer type if necessary. */
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if (!is_prototyped)
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{
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if (type->length () < builtin->builtin_int->length ())
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type = builtin->builtin_int;
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}
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/* Currently all target ABIs require at least the width of an integer
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type for an argument. We may have to conditionalize the following
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type coercion for future targets. */
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if (type->length () < builtin->builtin_int->length ())
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type = builtin->builtin_int;
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break;
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case TYPE_CODE_FLT:
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if (!is_prototyped && coerce_float_to_double_p)
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{
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if (type->length () < builtin->builtin_double->length ())
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type = builtin->builtin_double;
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else if (type->length () > builtin->builtin_double->length ())
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type = builtin->builtin_long_double;
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}
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break;
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case TYPE_CODE_FUNC:
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type = lookup_pointer_type (type);
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break;
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case TYPE_CODE_ARRAY:
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/* Arrays are coerced to pointers to their first element, unless
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they are vectors, in which case we want to leave them alone,
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because they are passed by value. */
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if (current_language->c_style_arrays_p ())
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if (!type->is_vector ())
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type = lookup_pointer_type (type->target_type ());
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break;
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case TYPE_CODE_UNDEF:
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case TYPE_CODE_PTR:
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case TYPE_CODE_STRUCT:
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case TYPE_CODE_UNION:
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case TYPE_CODE_VOID:
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case TYPE_CODE_SET:
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case TYPE_CODE_RANGE:
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case TYPE_CODE_STRING:
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case TYPE_CODE_ERROR:
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case TYPE_CODE_MEMBERPTR:
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case TYPE_CODE_METHODPTR:
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case TYPE_CODE_METHOD:
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case TYPE_CODE_COMPLEX:
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default:
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break;
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}
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return value_cast (type, arg);
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}
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/* See infcall.h. */
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CORE_ADDR
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find_function_addr (struct value *function,
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struct type **retval_type,
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struct type **function_type)
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{
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struct type *ftype = check_typedef (value_type (function));
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struct gdbarch *gdbarch = ftype->arch ();
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struct type *value_type = NULL;
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/* Initialize it just to avoid a GCC false warning. */
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CORE_ADDR funaddr = 0;
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/* If it's a member function, just look at the function
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part of it. */
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/* Determine address to call. */
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if (ftype->code () == TYPE_CODE_FUNC
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|| ftype->code () == TYPE_CODE_METHOD)
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funaddr = value_address (function);
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else if (ftype->code () == TYPE_CODE_PTR)
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{
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funaddr = value_as_address (function);
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ftype = check_typedef (ftype->target_type ());
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if (ftype->code () == TYPE_CODE_FUNC
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|| ftype->code () == TYPE_CODE_METHOD)
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funaddr = gdbarch_convert_from_func_ptr_addr
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(gdbarch, funaddr, current_inferior ()->top_target());
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}
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if (ftype->code () == TYPE_CODE_FUNC
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|| ftype->code () == TYPE_CODE_METHOD)
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{
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if (ftype->is_gnu_ifunc ())
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{
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CORE_ADDR resolver_addr = funaddr;
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/* Resolve the ifunc. Note this may call the resolver
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function in the inferior. */
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funaddr = gnu_ifunc_resolve_addr (gdbarch, resolver_addr);
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/* Skip querying the function symbol if no RETVAL_TYPE or
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FUNCTION_TYPE have been asked for. */
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if (retval_type != NULL || function_type != NULL)
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{
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type *target_ftype = find_function_type (funaddr);
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/* If we don't have debug info for the target function,
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see if we can instead extract the target function's
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type from the type that the resolver returns. */
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if (target_ftype == NULL)
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target_ftype = find_gnu_ifunc_target_type (resolver_addr);
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if (target_ftype != NULL)
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{
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value_type = check_typedef (target_ftype)->target_type ();
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ftype = target_ftype;
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}
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}
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}
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else
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value_type = ftype->target_type ();
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}
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else if (ftype->code () == TYPE_CODE_INT)
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{
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/* Handle the case of functions lacking debugging info.
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Their values are characters since their addresses are char. */
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if (ftype->length () == 1)
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funaddr = value_as_address (value_addr (function));
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else
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{
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/* Handle function descriptors lacking debug info. */
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int found_descriptor = 0;
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funaddr = 0; /* pacify "gcc -Werror" */
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if (VALUE_LVAL (function) == lval_memory)
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{
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CORE_ADDR nfunaddr;
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funaddr = value_as_address (value_addr (function));
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nfunaddr = funaddr;
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funaddr = gdbarch_convert_from_func_ptr_addr
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(gdbarch, funaddr, current_inferior ()->top_target ());
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if (funaddr != nfunaddr)
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found_descriptor = 1;
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}
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if (!found_descriptor)
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/* Handle integer used as address of a function. */
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funaddr = (CORE_ADDR) value_as_long (function);
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}
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}
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else
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error (_("Invalid data type for function to be called."));
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if (retval_type != NULL)
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*retval_type = value_type;
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if (function_type != NULL)
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*function_type = ftype;
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return funaddr + gdbarch_deprecated_function_start_offset (gdbarch);
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}
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/* For CALL_DUMMY_ON_STACK, push a breakpoint sequence that the called
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function returns to. */
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static CORE_ADDR
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push_dummy_code (struct gdbarch *gdbarch,
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CORE_ADDR sp, CORE_ADDR funaddr,
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gdb::array_view<value *> args,
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struct type *value_type,
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CORE_ADDR *real_pc, CORE_ADDR *bp_addr,
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struct regcache *regcache)
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{
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gdb_assert (gdbarch_push_dummy_code_p (gdbarch));
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return gdbarch_push_dummy_code (gdbarch, sp, funaddr,
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args.data (), args.size (),
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value_type, real_pc, bp_addr,
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regcache);
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}
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/* See infcall.h. */
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void
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error_call_unknown_return_type (const char *func_name)
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{
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if (func_name != NULL)
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error (_("'%s' has unknown return type; "
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"cast the call to its declared return type"),
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func_name);
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else
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error (_("function has unknown return type; "
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"cast the call to its declared return type"));
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}
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/* Fetch the name of the function at FUNADDR.
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This is used in printing an error message for call_function_by_hand.
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BUF is used to print FUNADDR in hex if the function name cannot be
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determined. It must be large enough to hold formatted result of
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RAW_FUNCTION_ADDRESS_FORMAT. */
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static const char *
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get_function_name (CORE_ADDR funaddr, char *buf, int buf_size)
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{
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{
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struct symbol *symbol = find_pc_function (funaddr);
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if (symbol)
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return symbol->print_name ();
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}
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{
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/* Try the minimal symbols. */
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struct bound_minimal_symbol msymbol = lookup_minimal_symbol_by_pc (funaddr);
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if (msymbol.minsym)
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return msymbol.minsym->print_name ();
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}
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{
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std::string tmp = string_printf (_(RAW_FUNCTION_ADDRESS_FORMAT),
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hex_string (funaddr));
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gdb_assert (tmp.length () + 1 <= buf_size);
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return strcpy (buf, tmp.c_str ());
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}
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}
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/* All the meta data necessary to extract the call's return value. */
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struct call_return_meta_info
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{
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/* The caller frame's architecture. */
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struct gdbarch *gdbarch;
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/* The called function. */
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struct value *function;
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/* The return value's type. */
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struct type *value_type;
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/* Are we returning a value using a structure return or a normal
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value return? */
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int struct_return_p;
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/* If using a structure return, this is the structure's address. */
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CORE_ADDR struct_addr;
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};
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/* Extract the called function's return value. */
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static struct value *
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get_call_return_value (struct call_return_meta_info *ri)
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{
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struct value *retval = NULL;
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thread_info *thr = inferior_thread ();
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bool stack_temporaries = thread_stack_temporaries_enabled_p (thr);
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if (ri->value_type->code () == TYPE_CODE_VOID)
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retval = allocate_value (ri->value_type);
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else if (ri->struct_return_p)
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{
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if (stack_temporaries)
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{
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retval = value_from_contents_and_address (ri->value_type, NULL,
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ri->struct_addr);
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push_thread_stack_temporary (thr, retval);
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}
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else
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retval = value_at_non_lval (ri->value_type, ri->struct_addr);
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}
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else
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{
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gdbarch_return_value_as_value (ri->gdbarch, ri->function, ri->value_type,
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get_current_regcache (),
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&retval, NULL);
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if (stack_temporaries && class_or_union_p (ri->value_type))
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{
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/* Values of class type returned in registers are copied onto
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the stack and their lval_type set to lval_memory. This is
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required because further evaluation of the expression
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could potentially invoke methods on the return value
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|
requiring GDB to evaluate the "this" pointer. To evaluate
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the this pointer, GDB needs the memory address of the
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value. */
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value_force_lval (retval, ri->struct_addr);
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push_thread_stack_temporary (thr, retval);
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}
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}
|
|
|
|
gdb_assert (retval != NULL);
|
|
return retval;
|
|
}
|
|
|
|
/* Data for the FSM that manages an infcall. It's main job is to
|
|
record the called function's return value. */
|
|
|
|
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)
|
|
{
|
|
INFCALL_SCOPED_DEBUG_ENTER_EXIT;
|
|
|
|
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 (std::unique_ptr<call_thread_fsm> sm,
|
|
struct thread_info *call_thread, CORE_ADDR real_pc)
|
|
{
|
|
INFCALL_SCOPED_DEBUG_ENTER_EXIT;
|
|
|
|
struct gdb_exception caught_error;
|
|
ptid_t call_thread_ptid = call_thread->ptid;
|
|
int was_running = call_thread->state == THREAD_RUNNING;
|
|
|
|
infcall_debug_printf ("call function at %s in thread %s, was_running = %d",
|
|
core_addr_to_string (real_pc),
|
|
call_thread_ptid.to_string ().c_str (),
|
|
was_running);
|
|
|
|
current_ui->unregister_file_handler ();
|
|
|
|
scoped_restore restore_in_infcall
|
|
= make_scoped_restore (&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). */
|
|
call_thread->set_thread_fsm (std::move (sm));
|
|
|
|
disable_watchpoints_before_interactive_call_start ();
|
|
|
|
/* We want to print return value, please... */
|
|
call_thread->control.proceed_to_finish = 1;
|
|
|
|
try
|
|
{
|
|
/* Infcalls run synchronously, in the foreground. */
|
|
scoped_restore restore_prompt_state
|
|
= make_scoped_restore (¤t_ui->prompt_state, PROMPT_BLOCKED);
|
|
|
|
/* So that we don't print the prompt prematurely in
|
|
fetch_inferior_event. */
|
|
scoped_restore restore_ui_async
|
|
= make_scoped_restore (¤t_ui->async, 0);
|
|
|
|
proceed (real_pc, GDB_SIGNAL_0);
|
|
|
|
infrun_debug_show_threads ("non-exited threads after proceed for inferior-call",
|
|
all_non_exited_threads ());
|
|
|
|
/* Inferior function calls are always synchronous, even if the
|
|
target supports asynchronous execution. */
|
|
wait_sync_command_done ();
|
|
|
|
infcall_debug_printf ("inferior call completed successfully");
|
|
}
|
|
catch (gdb_exception &e)
|
|
{
|
|
infcall_debug_printf ("exception while making inferior call (%d): %s",
|
|
e.reason, e.what ());
|
|
caught_error = std::move (e);
|
|
}
|
|
|
|
infcall_debug_printf ("thread is now: %s",
|
|
inferior_ptid.to_string ().c_str ());
|
|
|
|
/* 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. */
|
|
if (current_ui->prompt_state == PROMPT_BLOCKED)
|
|
current_ui->unregister_file_handler ();
|
|
else
|
|
current_ui->register_file_handler ();
|
|
|
|
/* 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 (call_thread->inf->process_target (),
|
|
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);
|
|
}
|
|
|
|
return caught_error;
|
|
}
|
|
|
|
/* Reserve space on the stack for a value of the given type.
|
|
Return the address of the allocated space.
|
|
Make certain that the value is correctly aligned.
|
|
The SP argument is modified. */
|
|
|
|
static CORE_ADDR
|
|
reserve_stack_space (const type *values_type, CORE_ADDR &sp)
|
|
{
|
|
frame_info_ptr frame = get_current_frame ();
|
|
struct gdbarch *gdbarch = get_frame_arch (frame);
|
|
CORE_ADDR addr = 0;
|
|
|
|
if (gdbarch_inner_than (gdbarch, 1, 2))
|
|
{
|
|
/* Stack grows downward. Align STRUCT_ADDR and SP after
|
|
making space. */
|
|
sp -= values_type->length ();
|
|
if (gdbarch_frame_align_p (gdbarch))
|
|
sp = gdbarch_frame_align (gdbarch, sp);
|
|
addr = sp;
|
|
}
|
|
else
|
|
{
|
|
/* Stack grows upward. Align the frame, allocate space, and
|
|
then again, re-align the frame??? */
|
|
if (gdbarch_frame_align_p (gdbarch))
|
|
sp = gdbarch_frame_align (gdbarch, sp);
|
|
addr = sp;
|
|
sp += values_type->length ();
|
|
if (gdbarch_frame_align_p (gdbarch))
|
|
sp = gdbarch_frame_align (gdbarch, sp);
|
|
}
|
|
|
|
return addr;
|
|
}
|
|
|
|
/* The data structure which keeps a destructor function and
|
|
its implicit 'this' parameter. */
|
|
|
|
struct destructor_info
|
|
{
|
|
destructor_info (struct value *function, struct value *self)
|
|
: function (function), self (self) { }
|
|
|
|
struct value *function;
|
|
struct value *self;
|
|
};
|
|
|
|
|
|
/* Auxiliary function that takes a list of destructor functions
|
|
with their 'this' parameters, and invokes the functions. */
|
|
|
|
static void
|
|
call_destructors (const std::list<destructor_info> &dtors_to_invoke,
|
|
struct type *default_return_type)
|
|
{
|
|
for (auto vals : dtors_to_invoke)
|
|
{
|
|
call_function_by_hand (vals.function, default_return_type,
|
|
gdb::make_array_view (&(vals.self), 1));
|
|
}
|
|
}
|
|
|
|
/* 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
|
|
(why not just save registers in GDB?). The purpose of pushing a dummy
|
|
frame which looks just like a real frame is so that if you call a
|
|
function and then hit a breakpoint (get a signal, etc), "backtrace"
|
|
will look right. Whether the backtrace needs to actually show the
|
|
stack at the time the inferior function was called is debatable, but
|
|
it certainly needs to not display garbage. So if you are contemplating
|
|
making dummy frames be different from normal frames, consider that. */
|
|
|
|
/* Perform a function call in the inferior.
|
|
ARGS is a vector of values of arguments.
|
|
FUNCTION is a value, the function to be called.
|
|
Returns a value representing what the function returned.
|
|
May fail to return, if a breakpoint or signal is hit
|
|
during the execution of the function.
|
|
|
|
ARGS is modified to contain coerced values. */
|
|
|
|
struct value *
|
|
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)
|
|
{
|
|
INFCALL_SCOPED_DEBUG_ENTER_EXIT;
|
|
|
|
CORE_ADDR sp;
|
|
struct type *target_values_type;
|
|
function_call_return_method return_method = return_method_normal;
|
|
CORE_ADDR struct_addr = 0;
|
|
CORE_ADDR real_pc;
|
|
CORE_ADDR bp_addr;
|
|
struct frame_id dummy_id;
|
|
frame_info_ptr frame;
|
|
struct gdbarch *gdbarch;
|
|
ptid_t call_thread_ptid;
|
|
struct gdb_exception e;
|
|
char name_buf[RAW_FUNCTION_ADDRESS_SIZE];
|
|
|
|
if (!may_call_functions_p)
|
|
error (_("Cannot call functions in the program: "
|
|
"may-call-functions is off."));
|
|
|
|
if (!target_has_execution ())
|
|
noprocess ();
|
|
|
|
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 ());
|
|
|
|
bool stack_temporaries = thread_stack_temporaries_enabled_p (call_thread.get ());
|
|
|
|
frame = get_current_frame ();
|
|
frame.prepare_reinflate ();
|
|
gdbarch = get_frame_arch (frame);
|
|
|
|
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 (is_nocall_function (ftype))
|
|
error (_("Cannot call the function '%s' which does not follow the "
|
|
"target calling convention."),
|
|
get_function_name (funaddr, name_buf, sizeof (name_buf)));
|
|
|
|
frame.reinflate ();
|
|
|
|
if (values_type == NULL || values_type->is_stub ())
|
|
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 () < ftype->num_fields ())
|
|
error (_("Too few arguments in function call."));
|
|
|
|
infcall_debug_printf ("calling %s", get_function_name (funaddr, name_buf,
|
|
sizeof (name_buf)));
|
|
|
|
/* 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. 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 (frame);
|
|
|
|
if (gdbarch_frame_align_p (gdbarch))
|
|
{
|
|
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 (gdbarch, 1, 2))
|
|
sp -= gdbarch_frame_red_zone_size (gdbarch);
|
|
else
|
|
sp += gdbarch_frame_red_zone_size (gdbarch);
|
|
/* Still aligned? */
|
|
gdb_assert (sp == gdbarch_frame_align (gdbarch, sp));
|
|
/* NOTE: cagney/2002-09-18:
|
|
|
|
On a RISC architecture, a void parameterless generic dummy
|
|
frame (i.e., no parameters, no result) typically does not
|
|
need to push anything the stack and hence can leave SP and
|
|
FP. Similarly, a frameless (possibly leaf) function does
|
|
not push anything on the stack and, hence, that too can
|
|
leave FP and SP unchanged. As a consequence, a sequence of
|
|
void parameterless generic dummy frame calls to frameless
|
|
functions will create a sequence of effectively identical
|
|
frames (SP, FP and TOS and PC the same). This, not
|
|
surprisingly, results in what appears to be a stack in an
|
|
infinite loop --- when GDB tries to find a generic dummy
|
|
frame on the internal dummy frame stack, it will always
|
|
find the first one.
|
|
|
|
To avoid this problem, the code below always grows the
|
|
stack. That way, two dummy frames can never be identical.
|
|
It does burn a few bytes of stack but that is a small price
|
|
to pay :-). */
|
|
if (sp == old_sp)
|
|
{
|
|
if (gdbarch_inner_than (gdbarch, 1, 2))
|
|
/* Stack grows down. */
|
|
sp = gdbarch_frame_align (gdbarch, old_sp - 1);
|
|
else
|
|
/* Stack grows up. */
|
|
sp = gdbarch_frame_align (gdbarch, old_sp + 1);
|
|
}
|
|
/* 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!
|
|
|
|
Who knows how badly aligned the SP is!
|
|
|
|
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 dummy_id().
|
|
|
|
If the ABI specifies a "Red Zone" (see the doco) the code
|
|
below will quietly trash it. */
|
|
sp = old_sp;
|
|
|
|
/* Skip over the stack temporaries that might have been generated during
|
|
the evaluation of an expression. */
|
|
if (stack_temporaries)
|
|
{
|
|
struct value *lastval;
|
|
|
|
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 + value_type (lastval)->length ();
|
|
}
|
|
|
|
if (gdbarch_frame_align_p (gdbarch))
|
|
sp = gdbarch_frame_align (gdbarch, sp);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Are we returning a value using a structure return? */
|
|
|
|
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
|
|
function returning a structure or union, needs to make space for
|
|
not just the breakpoint but also an extra word containing the
|
|
size (?) of the structure being passed. */
|
|
|
|
switch (gdbarch_call_dummy_location (gdbarch))
|
|
{
|
|
case ON_STACK:
|
|
{
|
|
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:
|
|
{
|
|
CORE_ADDR dummy_addr;
|
|
|
|
real_pc = funaddr;
|
|
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;
|
|
}
|
|
default:
|
|
internal_error (_("bad switch"));
|
|
}
|
|
|
|
/* Coerce the arguments and handle pass-by-reference.
|
|
We want to remember the destruction required for pass-by-ref values.
|
|
For these, store the dtor function and the 'this' argument
|
|
in DTORS_TO_INVOKE. */
|
|
std::list<destructor_info> dtors_to_invoke;
|
|
|
|
for (int i = args.size () - 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 (ftype->code () == TYPE_CODE_METHOD)
|
|
prototyped = 1;
|
|
else if (ftype->target_type () == NULL && ftype->num_fields () == 0
|
|
&& default_return_type != NULL)
|
|
{
|
|
/* 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 < ftype->num_fields ())
|
|
prototyped = ftype->is_prototyped ();
|
|
else
|
|
prototyped = 0;
|
|
|
|
if (i < ftype->num_fields ())
|
|
param_type = ftype->field (i).type ();
|
|
else
|
|
param_type = NULL;
|
|
|
|
value *original_arg = args[i];
|
|
args[i] = value_arg_coerce (gdbarch, args[i],
|
|
param_type, prototyped);
|
|
|
|
if (param_type == NULL)
|
|
continue;
|
|
|
|
auto info = language_pass_by_reference (param_type);
|
|
if (!info.copy_constructible)
|
|
error (_("expression cannot be evaluated because the type '%s' "
|
|
"is not copy constructible"), param_type->name ());
|
|
|
|
if (!info.destructible)
|
|
error (_("expression cannot be evaluated because the type '%s' "
|
|
"is not destructible"), param_type->name ());
|
|
|
|
if (info.trivially_copyable)
|
|
continue;
|
|
|
|
/* Make a copy of the argument on the stack. If the argument is
|
|
trivially copy ctor'able, copy bit by bit. Otherwise, call
|
|
the copy ctor to initialize the clone. */
|
|
CORE_ADDR addr = reserve_stack_space (param_type, sp);
|
|
value *clone
|
|
= value_from_contents_and_address (param_type, nullptr, addr);
|
|
push_thread_stack_temporary (call_thread.get (), clone);
|
|
value *clone_ptr
|
|
= value_from_pointer (lookup_pointer_type (param_type), addr);
|
|
|
|
if (info.trivially_copy_constructible)
|
|
{
|
|
int length = param_type->length ();
|
|
write_memory (addr, value_contents (args[i]).data (), length);
|
|
}
|
|
else
|
|
{
|
|
value *copy_ctor;
|
|
value *cctor_args[2] = { clone_ptr, original_arg };
|
|
find_overload_match (gdb::make_array_view (cctor_args, 2),
|
|
param_type->name (), METHOD,
|
|
&clone_ptr, nullptr, ©_ctor, nullptr,
|
|
nullptr, 0, EVAL_NORMAL);
|
|
|
|
if (copy_ctor == nullptr)
|
|
error (_("expression cannot be evaluated because a copy "
|
|
"constructor for the type '%s' could not be found "
|
|
"(maybe inlined?)"), param_type->name ());
|
|
|
|
call_function_by_hand (copy_ctor, default_return_type,
|
|
gdb::make_array_view (cctor_args, 2));
|
|
}
|
|
|
|
/* If the argument has a destructor, remember it so that we
|
|
invoke it after the infcall is complete. */
|
|
if (!info.trivially_destructible)
|
|
{
|
|
/* Looking up the function via overload resolution does not
|
|
work because the compiler (in particular, gcc) adds an
|
|
artificial int parameter in some cases. So we look up
|
|
the function by using the "~" name. This should be OK
|
|
because there can be only one dtor definition. */
|
|
const char *dtor_name = nullptr;
|
|
for (int fieldnum = 0;
|
|
fieldnum < TYPE_NFN_FIELDS (param_type);
|
|
fieldnum++)
|
|
{
|
|
fn_field *fn
|
|
= TYPE_FN_FIELDLIST1 (param_type, fieldnum);
|
|
const char *field_name
|
|
= TYPE_FN_FIELDLIST_NAME (param_type, fieldnum);
|
|
|
|
if (field_name[0] == '~')
|
|
dtor_name = TYPE_FN_FIELD_PHYSNAME (fn, 0);
|
|
}
|
|
|
|
if (dtor_name == nullptr)
|
|
error (_("expression cannot be evaluated because a destructor "
|
|
"for the type '%s' could not be found "
|
|
"(maybe inlined?)"), param_type->name ());
|
|
|
|
value *dtor
|
|
= find_function_in_inferior (dtor_name, 0);
|
|
|
|
/* Insert the dtor to the front of the list to call them
|
|
in reverse order later. */
|
|
dtors_to_invoke.emplace_front (dtor, clone_ptr);
|
|
}
|
|
|
|
args[i] = clone_ptr;
|
|
}
|
|
|
|
/* Reserve space for the return structure to be written on the
|
|
stack, if necessary.
|
|
|
|
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.
|
|
|
|
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)))
|
|
struct_addr = reserve_stack_space (values_type, 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 (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 dummy_id to form
|
|
the frame ID's stack address. */
|
|
dummy_id = frame_id_build (sp, bp_addr);
|
|
|
|
/* Create a momentary breakpoint at the return address of the
|
|
inferior. That way it breaks when it returns. */
|
|
|
|
{
|
|
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
|
|
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_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.. */
|
|
|
|
{
|
|
/* Save the current FSM. We'll override it. */
|
|
std::unique_ptr<thread_fsm> saved_sm = call_thread->release_thread_fsm ();
|
|
struct call_thread_fsm *sm;
|
|
|
|
/* 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);
|
|
{
|
|
std::unique_ptr<call_thread_fsm> sm_up (sm);
|
|
e = run_inferior_call (std::move (sm_up), call_thread.get (), real_pc);
|
|
}
|
|
|
|
if (e.reason < 0)
|
|
infcall_debug_printf ("after inferior call, exception (%d): %s",
|
|
e.reason, e.what ());
|
|
infcall_debug_printf ("after inferior call, thread state is: %s",
|
|
thread_state_string (call_thread->state));
|
|
|
|
gdb::observers::inferior_call_post.notify (call_thread_ptid, funaddr);
|
|
|
|
if (call_thread->state != THREAD_EXITED)
|
|
{
|
|
/* The FSM should still be the same. */
|
|
gdb_assert (call_thread->thread_fsm () == sm);
|
|
|
|
if (call_thread->thread_fsm ()->finished_p ())
|
|
{
|
|
struct value *retval;
|
|
|
|
infcall_debug_printf ("call completed");
|
|
|
|
/* 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;
|
|
|
|
/* Restore the original FSM and clean up / destroh the call FSM.
|
|
Doing it in this order ensures that if the call to clean_up
|
|
throws, the original FSM is properly restored. */
|
|
{
|
|
std::unique_ptr<thread_fsm> finalizing
|
|
= call_thread->release_thread_fsm ();
|
|
call_thread->set_thread_fsm (std::move (saved_sm));
|
|
|
|
finalizing->clean_up (call_thread.get ());
|
|
}
|
|
|
|
maybe_remove_breakpoints ();
|
|
|
|
gdb_assert (retval != NULL);
|
|
|
|
/* Destruct the pass-by-ref argument clones. */
|
|
call_destructors (dtors_to_invoke, default_return_type);
|
|
|
|
return retval;
|
|
}
|
|
else
|
|
infcall_debug_printf ("call did not complete");
|
|
|
|
/* Didn't complete. Clean up / destroy the call FSM, and restore the
|
|
previous state machine, and handle the error. */
|
|
{
|
|
std::unique_ptr<thread_fsm> finalizing
|
|
= call_thread->release_thread_fsm ();
|
|
call_thread->set_thread_fsm (std::move (saved_sm));
|
|
|
|
finalizing->clean_up (call_thread.get ());
|
|
}
|
|
}
|
|
}
|
|
|
|
/* 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. */
|
|
|
|
if (unwind_on_signal_p)
|
|
{
|
|
/* The user wants the context restored. */
|
|
|
|
/* 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 ());
|
|
|
|
/* 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\n\
|
|
(%s) will be abandoned."),
|
|
name.c_str ());
|
|
}
|
|
else
|
|
{
|
|
/* The user wants to stay in the frame where we stopped
|
|
(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\n\
|
|
(%s) will be abandoned.\n\
|
|
When the function is done executing, GDB will silently stop."),
|
|
name.c_str ());
|
|
}
|
|
}
|
|
|
|
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.
|
|
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,
|
|
GDB would be able to resume evaluation of the expression
|
|
when the function finally is done executing. Perhaps
|
|
someday this will be implemented (it would not be easy). */
|
|
/* 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 stopped 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."),
|
|
name.c_str ());
|
|
}
|
|
|
|
}
|
|
|
|
/* The above code errors out, so ... */
|
|
gdb_assert_not_reached ("... should not be here");
|
|
}
|
|
|
|
void _initialize_infcall ();
|
|
void
|
|
_initialize_infcall ()
|
|
{
|
|
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."), _("\
|
|
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."),
|
|
NULL,
|
|
show_coerce_float_to_double_p,
|
|
&setlist, &showlist);
|
|
|
|
add_setshow_boolean_cmd ("unwindonsignal", no_class,
|
|
&unwind_on_signal_p, _("\
|
|
Set unwinding of stack if a signal is received while in a call dummy."), _("\
|
|
Show unwinding of stack if a signal is received while in a call dummy."), _("\
|
|
The unwindonsignal lets the user determine what gdb should do if a signal\n\
|
|
is received while in a function called from gdb (call dummy). If set, gdb\n\
|
|
unwinds the stack and restore the context to what as it was before the call.\n\
|
|
The default is to stop in the frame where the signal was received."),
|
|
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);
|
|
|
|
add_setshow_boolean_cmd
|
|
("infcall", class_maintenance, &debug_infcall,
|
|
_("Set inferior call debugging."),
|
|
_("Show inferior call debugging."),
|
|
_("When on, inferior function call specific debugging is enabled."),
|
|
NULL, show_debug_infcall, &setdebuglist, &showdebuglist);
|
|
}
|