892 lines
31 KiB
C
892 lines
31 KiB
C
/* Perform an inferior function call, for GDB, the GNU debugger.
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Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
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1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
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2008 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 "breakpoint.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 "gdb_assert.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 "gdb_string.h"
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#include "infcall.h"
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#include "dummy-frame.h"
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#include "ada-lang.h"
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#include "gdbthread.h"
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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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/* 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_FLAG_PROTOTYPED flag may be clear, even if the function was
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defined in prototype style. When calling a function whose
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TYPE_FLAG_PROTOTYPED flag is clear, GDB consults this flag to
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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 int coerce_float_to_double_p = 1;
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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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fprintf_filtered (file, _("\
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Coercion of floats to doubles 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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int unwind_on_signal_p = 0;
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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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fprintf_filtered (file, _("\
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Unwinding of stack if a signal is received 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 or Ada 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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SP is the stack pointer were additional data can be pushed (updating
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its value as needed). */
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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, CORE_ADDR *sp)
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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-specific coercion first. */
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if (current_language->la_language == language_ada)
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arg = ada_convert_actual (arg, type, sp);
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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 (type))
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{
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case TYPE_CODE_REF:
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{
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struct value *new_value;
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if (TYPE_CODE (arg_type) == TYPE_CODE_REF)
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return value_cast_pointers (type, arg);
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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 (type), arg);
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new_value = value_ref (new_value);
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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 (type) < TYPE_LENGTH (builtin->builtin_int))
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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 (type) < TYPE_LENGTH (builtin->builtin_int))
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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 (type) < TYPE_LENGTH (builtin->builtin_double))
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type = builtin->builtin_double;
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else if (TYPE_LENGTH (type) > TYPE_LENGTH (builtin->builtin_double))
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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)
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if (!TYPE_VECTOR (type))
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type = lookup_pointer_type (TYPE_TARGET_TYPE (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_BITSTRING:
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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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/* Determine a function's address and its return type from its value.
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Calls error() if the function is not valid for calling. */
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CORE_ADDR
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find_function_addr (struct value *function, struct type **retval_type)
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{
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struct type *ftype = check_typedef (value_type (function));
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enum type_code code = TYPE_CODE (ftype);
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struct type *value_type = NULL;
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CORE_ADDR funaddr;
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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 (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD)
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{
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funaddr = VALUE_ADDRESS (function);
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value_type = TYPE_TARGET_TYPE (ftype);
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}
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else if (code == TYPE_CODE_PTR)
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{
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funaddr = value_as_address (function);
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ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
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if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
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|| TYPE_CODE (ftype) == TYPE_CODE_METHOD)
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{
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funaddr = gdbarch_convert_from_func_ptr_addr (current_gdbarch,
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funaddr,
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¤t_target);
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value_type = TYPE_TARGET_TYPE (ftype);
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}
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}
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else if (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 (TYPE_LENGTH (ftype) == 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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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 (current_gdbarch,
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funaddr,
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¤t_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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return funaddr + gdbarch_deprecated_function_start_offset (current_gdbarch);
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}
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/* Call breakpoint_auto_delete on the current contents of the bpstat
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of the current thread. */
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static void
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breakpoint_auto_delete_contents (void *arg)
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{
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if (!ptid_equal (inferior_ptid, null_ptid))
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breakpoint_auto_delete (inferior_thread ()->stop_bpstat);
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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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struct value **args, int nargs,
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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, nargs, value_type, real_pc, bp_addr,
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regcache);
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}
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/* All this stuff with a dummy frame may seem unnecessarily complicated
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(why not just save registers in GDB?). The purpose of pushing a dummy
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frame which looks just like a real frame is so that if you call a
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function and then hit a breakpoint (get a signal, etc), "backtrace"
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will look right. Whether the backtrace needs to actually show the
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stack at the time the inferior function was called is debatable, but
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it certainly needs to not display garbage. So if you are contemplating
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making dummy frames be different from normal frames, consider that. */
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/* Perform a function call in the inferior.
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ARGS is a vector of values of arguments (NARGS of them).
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FUNCTION is a value, the function to be called.
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Returns a value representing what the function returned.
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May fail to return, if a breakpoint or signal is hit
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during the execution of the function.
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ARGS is modified to contain coerced values. */
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struct value *
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call_function_by_hand (struct value *function, int nargs, struct value **args)
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{
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CORE_ADDR sp;
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CORE_ADDR dummy_addr;
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struct type *values_type, *target_values_type;
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unsigned char struct_return = 0, lang_struct_return = 0;
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CORE_ADDR struct_addr = 0;
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struct regcache *retbuf;
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struct cleanup *retbuf_cleanup;
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struct inferior_status *inf_status;
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struct cleanup *inf_status_cleanup;
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CORE_ADDR funaddr;
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CORE_ADDR real_pc;
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struct type *ftype = check_typedef (value_type (function));
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CORE_ADDR bp_addr;
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struct regcache *caller_regcache;
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struct cleanup *caller_regcache_cleanup;
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struct frame_id dummy_id;
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struct cleanup *args_cleanup;
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struct frame_info *frame;
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struct gdbarch *gdbarch;
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if (TYPE_CODE (ftype) == TYPE_CODE_PTR)
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ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
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if (!target_has_execution)
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noprocess ();
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frame = get_current_frame ();
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gdbarch = get_frame_arch (frame);
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if (!gdbarch_push_dummy_call_p (gdbarch))
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error (_("This target does not support function calls"));
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/* Create a cleanup chain that contains the retbuf (buffer
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containing the register values). This chain is create BEFORE the
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inf_status chain so that the inferior status can cleaned up
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(restored or discarded) without having the retbuf freed. */
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retbuf = regcache_xmalloc (gdbarch);
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retbuf_cleanup = make_cleanup_regcache_xfree (retbuf);
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/* A cleanup for the inferior status. Create this AFTER the retbuf
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so that this can be discarded or applied without interfering with
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the regbuf. */
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inf_status = save_inferior_status (1);
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inf_status_cleanup = make_cleanup_restore_inferior_status (inf_status);
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/* Save the caller's registers so that they can be restored once the
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callee returns. To allow nested calls the registers are (further
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down) pushed onto a dummy frame stack. Include a cleanup (which
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is tossed once the regcache has been pushed). */
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caller_regcache = frame_save_as_regcache (frame);
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caller_regcache_cleanup = make_cleanup_regcache_xfree (caller_regcache);
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/* Ensure that the initial SP is correctly aligned. */
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{
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CORE_ADDR old_sp = get_frame_sp (frame);
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if (gdbarch_frame_align_p (gdbarch))
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{
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sp = gdbarch_frame_align (gdbarch, old_sp);
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/* NOTE: cagney/2003-08-13: Skip the "red zone". For some
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ABIs, a function can use memory beyond the inner most stack
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address. AMD64 called that region the "red zone". Skip at
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least the "red zone" size before allocating any space on
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the stack. */
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if (gdbarch_inner_than (gdbarch, 1, 2))
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sp -= gdbarch_frame_red_zone_size (gdbarch);
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else
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sp += gdbarch_frame_red_zone_size (gdbarch);
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/* Still aligned? */
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gdb_assert (sp == gdbarch_frame_align (gdbarch, sp));
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/* NOTE: cagney/2002-09-18:
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On a RISC architecture, a void parameterless generic dummy
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frame (i.e., no parameters, no result) typically does not
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need to push anything the stack and hence can leave SP and
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FP. Similarly, a frameless (possibly leaf) function does
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not push anything on the stack and, hence, that too can
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leave FP and SP unchanged. As a consequence, a sequence of
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void parameterless generic dummy frame calls to frameless
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functions will create a sequence of effectively identical
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frames (SP, FP and TOS and PC the same). This, not
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suprisingly, results in what appears to be a stack in an
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infinite loop --- when GDB tries to find a generic dummy
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frame on the internal dummy frame stack, it will always
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find the first one.
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To avoid this problem, the code below always grows the
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stack. That way, two dummy frames can never be identical.
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It does burn a few bytes of stack but that is a small price
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to pay :-). */
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if (sp == old_sp)
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{
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if (gdbarch_inner_than (gdbarch, 1, 2))
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/* Stack grows down. */
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sp = gdbarch_frame_align (gdbarch, old_sp - 1);
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else
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/* Stack grows up. */
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sp = gdbarch_frame_align (gdbarch, old_sp + 1);
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}
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gdb_assert ((gdbarch_inner_than (gdbarch, 1, 2)
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&& sp <= old_sp)
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|| (gdbarch_inner_than (gdbarch, 2, 1)
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&& sp >= old_sp));
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}
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else
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/* FIXME: cagney/2002-09-18: Hey, you loose!
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Who knows how badly aligned the SP is!
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If the generic dummy frame ends up empty (because nothing is
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pushed) GDB won't be able to correctly perform back traces.
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If a target is having trouble with backtraces, first thing to
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do is add FRAME_ALIGN() to the architecture vector. If that
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fails, try dummy_id().
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If the ABI specifies a "Red Zone" (see the doco) the code
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below will quietly trash it. */
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sp = old_sp;
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}
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funaddr = find_function_addr (function, &values_type);
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if (!values_type)
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values_type = builtin_type (gdbarch)->builtin_int;
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CHECK_TYPEDEF (values_type);
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/* Are we returning a value using a structure return (passing a
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hidden argument pointing to storage) or a normal value return?
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There are two cases: language-mandated structure return and
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target ABI structure return. The variable STRUCT_RETURN only
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describes the latter. The language version is handled by passing
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the return location as the first parameter to the function,
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even preceding "this". This is different from the target
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ABI version, which is target-specific; for instance, on ia64
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the first argument is passed in out0 but the hidden structure
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return pointer would normally be passed in r8. */
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if (language_pass_by_reference (values_type))
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{
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lang_struct_return = 1;
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/* Tell the target specific argument pushing routine not to
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expect a value. */
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target_values_type = builtin_type_void;
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}
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else
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{
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struct_return = using_struct_return (value_type (function), values_type);
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target_values_type = values_type;
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}
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/* Determine the location of the breakpoint (and possibly other
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stuff) that the called function will return to. The SPARC, for a
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function returning a structure or union, needs to make space for
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not just the breakpoint but also an extra word containing the
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size (?) of the structure being passed. */
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/* The actual breakpoint (at BP_ADDR) is inserted separatly so there
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is no need to write that out. */
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switch (gdbarch_call_dummy_location (gdbarch))
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{
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case ON_STACK:
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/* "dummy_addr" is here just to keep old targets happy. New
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targets return that same information via "sp" and "bp_addr". */
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if (gdbarch_inner_than (gdbarch, 1, 2))
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{
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sp = push_dummy_code (gdbarch, sp, funaddr,
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args, nargs, target_values_type,
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&real_pc, &bp_addr, get_current_regcache ());
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dummy_addr = sp;
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}
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else
|
||
{
|
||
dummy_addr = sp;
|
||
sp = push_dummy_code (gdbarch, sp, funaddr,
|
||
args, nargs, target_values_type,
|
||
&real_pc, &bp_addr, get_current_regcache ());
|
||
}
|
||
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 (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;
|
||
|
||
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 (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;
|
||
}
|
||
default:
|
||
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 (gdbarch, args[i],
|
||
param_type, prototyped, &sp);
|
||
|
||
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. */
|
||
|
||
if (struct_return || lang_struct_return)
|
||
{
|
||
int len = TYPE_LENGTH (values_type);
|
||
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 (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 (gdbarch))
|
||
sp = gdbarch_frame_align (gdbarch, sp);
|
||
struct_addr = sp;
|
||
sp += len;
|
||
if (gdbarch_frame_align_p (gdbarch))
|
||
sp = gdbarch_frame_align (gdbarch, sp);
|
||
}
|
||
}
|
||
|
||
if (lang_struct_return)
|
||
{
|
||
struct value **new_args;
|
||
|
||
/* Add the new argument to the front of the argument list. */
|
||
new_args = xmalloc (sizeof (struct value *) * (nargs + 1));
|
||
new_args[0] = value_from_pointer (lookup_pointer_type (values_type),
|
||
struct_addr);
|
||
memcpy (&new_args[1], &args[0], sizeof (struct value *) * nargs);
|
||
args = new_args;
|
||
nargs++;
|
||
args_cleanup = make_cleanup (xfree, args);
|
||
}
|
||
else
|
||
args_cleanup = make_cleanup (null_cleanup, NULL);
|
||
|
||
/* 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, nargs, args,
|
||
sp, struct_return, struct_addr);
|
||
|
||
do_cleanups (args_cleanup);
|
||
|
||
/* 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. */
|
||
|
||
{
|
||
struct breakpoint *bpt;
|
||
struct symtab_and_line sal;
|
||
init_sal (&sal); /* initialize to zeroes */
|
||
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. */
|
||
bpt = set_momentary_breakpoint (sal, dummy_id, bp_call_dummy);
|
||
bpt->disposition = disp_del;
|
||
}
|
||
|
||
/* 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);
|
||
|
||
/* - 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);
|
||
struct cleanup *old_cleanups2;
|
||
int saved_async = 0;
|
||
struct thread_info *tp = inferior_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. */
|
||
make_cleanup (breakpoint_auto_delete_contents, NULL);
|
||
|
||
disable_watchpoints_before_interactive_call_start ();
|
||
tp->proceed_to_finish = 1; /* We want stop_registers, please... */
|
||
|
||
if (target_can_async_p ())
|
||
saved_async = target_async_mask (0);
|
||
|
||
old_cleanups2 = make_cleanup_restore_integer (&suppress_resume_observer);
|
||
suppress_resume_observer = 1;
|
||
make_cleanup_restore_integer (&suppress_stop_observer);
|
||
suppress_stop_observer = 1;
|
||
proceed (real_pc, TARGET_SIGNAL_0, 0);
|
||
do_cleanups (old_cleanups2);
|
||
|
||
if (saved_async)
|
||
target_async_mask (saved_async);
|
||
|
||
enable_watchpoints_after_interactive_call_stop ();
|
||
|
||
discard_cleanups (old_cleanups);
|
||
}
|
||
|
||
if (! target_has_execution)
|
||
{
|
||
/* If we try to restore the inferior status (via the cleanup),
|
||
we'll crash as the inferior is no longer running. */
|
||
discard_cleanups (inf_status_cleanup);
|
||
discard_inferior_status (inf_status);
|
||
error (_("\
|
||
The program being debugged exited while in a function called from GDB."));
|
||
}
|
||
|
||
if (stopped_by_random_signal || !stop_stack_dummy)
|
||
{
|
||
/* Find the name of the function we're about to complain about. */
|
||
const char *name = NULL;
|
||
{
|
||
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)
|
||
{
|
||
/* 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;
|
||
}
|
||
}
|
||
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. */
|
||
frame_pop (get_current_frame ());
|
||
|
||
/* 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);
|
||
}
|
||
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);
|
||
/* 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);
|
||
}
|
||
}
|
||
|
||
if (!stop_stack_dummy)
|
||
{
|
||
/* 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);
|
||
/* 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\
|
||
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);
|
||
}
|
||
|
||
/* 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 (lang_struct_return)
|
||
retval = value_at (values_type, struct_addr);
|
||
else if (TYPE_CODE (target_values_type) == TYPE_CODE_VOID)
|
||
{
|
||
/* If the function returns void, don't bother fetching the
|
||
return value. */
|
||
retval = allocate_value (values_type);
|
||
}
|
||
else
|
||
{
|
||
switch (gdbarch_return_value (gdbarch, value_type (function),
|
||
target_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 (gdbarch, value_type (function), 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;
|
||
}
|
||
}
|
||
|
||
|
||
/* Provide a prototype to silence -Wmissing-prototypes. */
|
||
void _initialize_infcall (void);
|
||
|
||
void
|
||
_initialize_infcall (void)
|
||
{
|
||
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.\n"),
|
||
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);
|
||
}
|