1 /* Perform non-arithmetic operations on values, for GDB.
2 Copyright 1986, 1987, 1989, 1991, 1992 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
33 /* Local functions. */
36 typecmp
PARAMS ((int staticp
, struct type
*t1
[], value t2
[]));
39 find_function_addr
PARAMS ((value
, struct type
**));
42 value_push
PARAMS ((CORE_ADDR
, value
));
45 value_arg_push
PARAMS ((CORE_ADDR
, value
));
48 search_struct_field
PARAMS ((char *, value
, int, struct type
*, int));
51 search_struct_method
PARAMS ((char *, value
*, value
*, int, int *,
55 check_field_in
PARAMS ((struct type
*, const char *));
58 allocate_space_in_inferior
PARAMS ((int));
61 /* Allocate NBYTES of space in the inferior using the inferior's malloc
62 and return a value that is a pointer to the allocated space. */
65 allocate_space_in_inferior (len
)
69 register struct symbol
*sym
;
70 struct minimal_symbol
*msymbol
;
75 /* Find the address of malloc in the inferior. */
77 sym
= lookup_symbol ("malloc", 0, VAR_NAMESPACE
, 0, NULL
);
80 if (SYMBOL_CLASS (sym
) != LOC_BLOCK
)
82 error ("\"malloc\" exists in this program but is not a function.");
84 val
= value_of_variable (sym
);
88 msymbol
= lookup_minimal_symbol ("malloc", (struct objfile
*) NULL
);
91 type
= lookup_pointer_type (builtin_type_char
);
92 type
= lookup_function_type (type
);
93 type
= lookup_pointer_type (type
);
94 maddr
= (LONGEST
) SYMBOL_VALUE_ADDRESS (msymbol
);
95 val
= value_from_longest (type
, maddr
);
99 error ("evaluation of this expression requires the program to have a function \"malloc\".");
103 blocklen
= value_from_longest (builtin_type_int
, (LONGEST
) len
);
104 val
= call_function_by_hand (val
, 1, &blocklen
);
105 if (value_logical_not (val
))
107 error ("No memory available to program.");
109 return (value_as_long (val
));
112 /* Cast value ARG2 to type TYPE and return as a value.
113 More general than a C cast: accepts any two types of the same length,
114 and if ARG2 is an lvalue it can be cast into anything at all. */
115 /* In C++, casts may change pointer or object representations. */
118 value_cast (type
, arg2
)
122 register enum type_code code1
;
123 register enum type_code code2
;
126 /* Coerce arrays but not enums. Enums will work as-is
127 and coercing them would cause an infinite recursion. */
128 if (TYPE_CODE (VALUE_TYPE (arg2
)) != TYPE_CODE_ENUM
)
131 code1
= TYPE_CODE (type
);
132 code2
= TYPE_CODE (VALUE_TYPE (arg2
));
133 scalar
= (code2
== TYPE_CODE_INT
|| code2
== TYPE_CODE_FLT
134 || code2
== TYPE_CODE_ENUM
);
136 if ( code1
== TYPE_CODE_STRUCT
137 && code2
== TYPE_CODE_STRUCT
138 && TYPE_NAME (type
) != 0)
140 /* Look in the type of the source to see if it contains the
141 type of the target as a superclass. If so, we'll need to
142 offset the object in addition to changing its type. */
143 value v
= search_struct_field (type_name_no_tag (type
),
144 arg2
, 0, VALUE_TYPE (arg2
), 1);
147 VALUE_TYPE (v
) = type
;
151 if (code1
== TYPE_CODE_FLT
&& scalar
)
152 return value_from_double (type
, value_as_double (arg2
));
153 else if ((code1
== TYPE_CODE_INT
|| code1
== TYPE_CODE_ENUM
)
154 && (scalar
|| code2
== TYPE_CODE_PTR
))
155 return value_from_longest (type
, value_as_long (arg2
));
156 else if (TYPE_LENGTH (type
) == TYPE_LENGTH (VALUE_TYPE (arg2
)))
158 if (code1
== TYPE_CODE_PTR
&& code2
== TYPE_CODE_PTR
)
160 /* Look in the type of the source to see if it contains the
161 type of the target as a superclass. If so, we'll need to
162 offset the pointer rather than just change its type. */
163 struct type
*t1
= TYPE_TARGET_TYPE (type
);
164 struct type
*t2
= TYPE_TARGET_TYPE (VALUE_TYPE (arg2
));
165 if ( TYPE_CODE (t1
) == TYPE_CODE_STRUCT
166 && TYPE_CODE (t2
) == TYPE_CODE_STRUCT
167 && TYPE_NAME (t1
) != 0) /* if name unknown, can't have supercl */
169 value v
= search_struct_field (type_name_no_tag (t1
),
170 value_ind (arg2
), 0, t2
, 1);
174 VALUE_TYPE (v
) = type
;
178 /* No superclass found, just fall through to change ptr type. */
180 VALUE_TYPE (arg2
) = type
;
183 else if (VALUE_LVAL (arg2
) == lval_memory
)
185 return value_at_lazy (type
, VALUE_ADDRESS (arg2
) + VALUE_OFFSET (arg2
));
187 else if (code1
== TYPE_CODE_VOID
)
189 return value_zero (builtin_type_void
, not_lval
);
193 error ("Invalid cast.");
198 /* Create a value of type TYPE that is zero, and return it. */
201 value_zero (type
, lv
)
205 register value val
= allocate_value (type
);
207 memset (VALUE_CONTENTS (val
), 0, TYPE_LENGTH (type
));
208 VALUE_LVAL (val
) = lv
;
213 /* Return a value with type TYPE located at ADDR.
215 Call value_at only if the data needs to be fetched immediately;
216 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
217 value_at_lazy instead. value_at_lazy simply records the address of
218 the data and sets the lazy-evaluation-required flag. The lazy flag
219 is tested in the VALUE_CONTENTS macro, which is used if and when
220 the contents are actually required. */
223 value_at (type
, addr
)
227 register value val
= allocate_value (type
);
229 read_memory (addr
, VALUE_CONTENTS_RAW (val
), TYPE_LENGTH (type
));
231 VALUE_LVAL (val
) = lval_memory
;
232 VALUE_ADDRESS (val
) = addr
;
237 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */
240 value_at_lazy (type
, addr
)
244 register value val
= allocate_value (type
);
246 VALUE_LVAL (val
) = lval_memory
;
247 VALUE_ADDRESS (val
) = addr
;
248 VALUE_LAZY (val
) = 1;
253 /* Called only from the VALUE_CONTENTS macro, if the current data for
254 a variable needs to be loaded into VALUE_CONTENTS(VAL). Fetches the
255 data from the user's process, and clears the lazy flag to indicate
256 that the data in the buffer is valid.
258 If the value is zero-length, we avoid calling read_memory, which would
259 abort. We mark the value as fetched anyway -- all 0 bytes of it.
261 This function returns a value because it is used in the VALUE_CONTENTS
262 macro as part of an expression, where a void would not work. The
266 value_fetch_lazy (val
)
269 CORE_ADDR addr
= VALUE_ADDRESS (val
) + VALUE_OFFSET (val
);
271 if (TYPE_LENGTH (VALUE_TYPE (val
)))
272 read_memory (addr
, VALUE_CONTENTS_RAW (val
),
273 TYPE_LENGTH (VALUE_TYPE (val
)));
274 VALUE_LAZY (val
) = 0;
279 /* Store the contents of FROMVAL into the location of TOVAL.
280 Return a new value with the location of TOVAL and contents of FROMVAL. */
283 value_assign (toval
, fromval
)
284 register value toval
, fromval
;
286 register struct type
*type
= VALUE_TYPE (toval
);
288 char raw_buffer
[MAX_REGISTER_RAW_SIZE
];
289 char virtual_buffer
[MAX_REGISTER_VIRTUAL_SIZE
];
292 COERCE_ARRAY (fromval
);
295 if (VALUE_LVAL (toval
) != lval_internalvar
)
296 fromval
= value_cast (type
, fromval
);
298 /* If TOVAL is a special machine register requiring conversion
299 of program values to a special raw format,
300 convert FROMVAL's contents now, with result in `raw_buffer',
301 and set USE_BUFFER to the number of bytes to write. */
303 if (VALUE_REGNO (toval
) >= 0
304 && REGISTER_CONVERTIBLE (VALUE_REGNO (toval
)))
306 int regno
= VALUE_REGNO (toval
);
307 if (VALUE_TYPE (fromval
) != REGISTER_VIRTUAL_TYPE (regno
))
308 fromval
= value_cast (REGISTER_VIRTUAL_TYPE (regno
), fromval
);
309 memcpy (virtual_buffer
, VALUE_CONTENTS (fromval
),
310 REGISTER_VIRTUAL_SIZE (regno
));
311 REGISTER_CONVERT_TO_RAW (regno
, virtual_buffer
, raw_buffer
);
312 use_buffer
= REGISTER_RAW_SIZE (regno
);
315 switch (VALUE_LVAL (toval
))
317 case lval_internalvar
:
318 set_internalvar (VALUE_INTERNALVAR (toval
), fromval
);
321 case lval_internalvar_component
:
322 set_internalvar_component (VALUE_INTERNALVAR (toval
),
323 VALUE_OFFSET (toval
),
324 VALUE_BITPOS (toval
),
325 VALUE_BITSIZE (toval
),
330 if (VALUE_BITSIZE (toval
))
332 int v
; /* FIXME, this won't work for large bitfields */
333 read_memory (VALUE_ADDRESS (toval
) + VALUE_OFFSET (toval
),
334 (char *) &v
, sizeof v
);
335 modify_field ((char *) &v
, (int) value_as_long (fromval
),
336 VALUE_BITPOS (toval
), VALUE_BITSIZE (toval
));
337 write_memory (VALUE_ADDRESS (toval
) + VALUE_OFFSET (toval
),
338 (char *)&v
, sizeof v
);
341 write_memory (VALUE_ADDRESS (toval
) + VALUE_OFFSET (toval
),
342 raw_buffer
, use_buffer
);
344 write_memory (VALUE_ADDRESS (toval
) + VALUE_OFFSET (toval
),
345 VALUE_CONTENTS (fromval
), TYPE_LENGTH (type
));
349 if (VALUE_BITSIZE (toval
))
353 read_register_bytes (VALUE_ADDRESS (toval
) + VALUE_OFFSET (toval
),
354 (char *) &v
, sizeof v
);
355 modify_field ((char *) &v
, (int) value_as_long (fromval
),
356 VALUE_BITPOS (toval
), VALUE_BITSIZE (toval
));
357 write_register_bytes (VALUE_ADDRESS (toval
) + VALUE_OFFSET (toval
),
358 (char *) &v
, sizeof v
);
361 write_register_bytes (VALUE_ADDRESS (toval
) + VALUE_OFFSET (toval
),
362 raw_buffer
, use_buffer
);
365 /* Do any conversion necessary when storing this type to more
366 than one register. */
367 #ifdef REGISTER_CONVERT_FROM_TYPE
368 memcpy (raw_buffer
, VALUE_CONTENTS (fromval
), TYPE_LENGTH (type
));
369 REGISTER_CONVERT_FROM_TYPE(VALUE_REGNO (toval
), type
, raw_buffer
);
370 write_register_bytes (VALUE_ADDRESS (toval
) + VALUE_OFFSET (toval
),
371 raw_buffer
, TYPE_LENGTH (type
));
373 write_register_bytes (VALUE_ADDRESS (toval
) + VALUE_OFFSET (toval
),
374 VALUE_CONTENTS (fromval
), TYPE_LENGTH (type
));
379 case lval_reg_frame_relative
:
381 /* value is stored in a series of registers in the frame
382 specified by the structure. Copy that value out, modify
383 it, and copy it back in. */
384 int amount_to_copy
= (VALUE_BITSIZE (toval
) ? 1 : TYPE_LENGTH (type
));
385 int reg_size
= REGISTER_RAW_SIZE (VALUE_FRAME_REGNUM (toval
));
386 int byte_offset
= VALUE_OFFSET (toval
) % reg_size
;
387 int reg_offset
= VALUE_OFFSET (toval
) / reg_size
;
389 char *buffer
= (char *) alloca (amount_to_copy
);
393 /* Figure out which frame this is in currently. */
394 for (frame
= get_current_frame ();
395 frame
&& FRAME_FP (frame
) != VALUE_FRAME (toval
);
396 frame
= get_prev_frame (frame
))
400 error ("Value being assigned to is no longer active.");
402 amount_to_copy
+= (reg_size
- amount_to_copy
% reg_size
);
405 for ((regno
= VALUE_FRAME_REGNUM (toval
) + reg_offset
,
407 amount_copied
< amount_to_copy
;
408 amount_copied
+= reg_size
, regno
++)
410 get_saved_register (buffer
+ amount_copied
,
411 (int *)NULL
, (CORE_ADDR
*)NULL
,
412 frame
, regno
, (enum lval_type
*)NULL
);
415 /* Modify what needs to be modified. */
416 if (VALUE_BITSIZE (toval
))
417 modify_field (buffer
+ byte_offset
,
418 (int) value_as_long (fromval
),
419 VALUE_BITPOS (toval
), VALUE_BITSIZE (toval
));
421 memcpy (buffer
+ byte_offset
, raw_buffer
, use_buffer
);
423 memcpy (buffer
+ byte_offset
, VALUE_CONTENTS (fromval
),
427 for ((regno
= VALUE_FRAME_REGNUM (toval
) + reg_offset
,
429 amount_copied
< amount_to_copy
;
430 amount_copied
+= reg_size
, regno
++)
436 /* Just find out where to put it. */
437 get_saved_register ((char *)NULL
,
438 &optim
, &addr
, frame
, regno
, &lval
);
441 error ("Attempt to assign to a value that was optimized out.");
442 if (lval
== lval_memory
)
443 write_memory (addr
, buffer
+ amount_copied
, reg_size
);
444 else if (lval
== lval_register
)
445 write_register_bytes (addr
, buffer
+ amount_copied
, reg_size
);
447 error ("Attempt to assign to an unmodifiable value.");
454 error ("Left side of = operation is not an lvalue.");
457 /* Return a value just like TOVAL except with the contents of FROMVAL
458 (except in the case of the type if TOVAL is an internalvar). */
460 if (VALUE_LVAL (toval
) == lval_internalvar
461 || VALUE_LVAL (toval
) == lval_internalvar_component
)
463 type
= VALUE_TYPE (fromval
);
466 val
= allocate_value (type
);
467 memcpy (val
, toval
, VALUE_CONTENTS_RAW (val
) - (char *) val
);
468 memcpy (VALUE_CONTENTS_RAW (val
), VALUE_CONTENTS (fromval
),
470 VALUE_TYPE (val
) = type
;
475 /* Extend a value VAL to COUNT repetitions of its type. */
478 value_repeat (arg1
, count
)
484 if (VALUE_LVAL (arg1
) != lval_memory
)
485 error ("Only values in memory can be extended with '@'.");
487 error ("Invalid number %d of repetitions.", count
);
489 val
= allocate_repeat_value (VALUE_TYPE (arg1
), count
);
491 read_memory (VALUE_ADDRESS (arg1
) + VALUE_OFFSET (arg1
),
492 VALUE_CONTENTS_RAW (val
),
493 TYPE_LENGTH (VALUE_TYPE (val
)) * count
);
494 VALUE_LVAL (val
) = lval_memory
;
495 VALUE_ADDRESS (val
) = VALUE_ADDRESS (arg1
) + VALUE_OFFSET (arg1
);
501 value_of_variable (var
)
506 val
= read_var_value (var
, (FRAME
) 0);
508 error ("Address of symbol \"%s\" is unknown.", SYMBOL_SOURCE_NAME (var
));
512 /* Given a value which is an array, return a value which is a pointer to its
513 first element, regardless of whether or not the array has a nonzero lower
516 FIXME: A previous comment here indicated that this routine should be
517 substracting the array's lower bound. It's not clear to me that this
518 is correct. Given an array subscripting operation, it would certainly
519 work to do the adjustment here, essentially computing:
521 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
523 However I believe a more appropriate and logical place to account for
524 the lower bound is to do so in value_subscript, essentially computing:
526 (&array[0] + ((index - lowerbound) * sizeof array[0]))
528 As further evidence consider what would happen with operations other
529 than array subscripting, where the caller would get back a value that
530 had an address somewhere before the actual first element of the array,
531 and the information about the lower bound would be lost because of
532 the coercion to pointer type.
536 value_coerce_array (arg1
)
539 register struct type
*type
;
541 if (VALUE_LVAL (arg1
) != lval_memory
)
542 error ("Attempt to take address of value not located in memory.");
544 /* Get type of elements. */
545 if (TYPE_CODE (VALUE_TYPE (arg1
)) == TYPE_CODE_ARRAY
)
546 type
= TYPE_TARGET_TYPE (VALUE_TYPE (arg1
));
548 /* A phony array made by value_repeat.
549 Its type is the type of the elements, not an array type. */
550 type
= VALUE_TYPE (arg1
);
552 return value_from_longest (lookup_pointer_type (type
),
553 (LONGEST
) (VALUE_ADDRESS (arg1
) + VALUE_OFFSET (arg1
)));
556 /* Given a value which is a function, return a value which is a pointer
560 value_coerce_function (arg1
)
564 if (VALUE_LVAL (arg1
) != lval_memory
)
565 error ("Attempt to take address of value not located in memory.");
567 return value_from_longest (lookup_pointer_type (VALUE_TYPE (arg1
)),
568 (LONGEST
) (VALUE_ADDRESS (arg1
) + VALUE_OFFSET (arg1
)));
571 /* Return a pointer value for the object for which ARG1 is the contents. */
577 struct type
*type
= VALUE_TYPE (arg1
);
578 if (TYPE_CODE (type
) == TYPE_CODE_REF
)
580 /* Copy the value, but change the type from (T&) to (T*).
581 We keep the same location information, which is efficient,
582 and allows &(&X) to get the location containing the reference. */
583 value arg2
= value_copy (arg1
);
584 VALUE_TYPE (arg2
) = lookup_pointer_type (TYPE_TARGET_TYPE (type
));
587 if (VALUE_REPEATED (arg1
)
588 || TYPE_CODE (type
) == TYPE_CODE_ARRAY
)
589 return value_coerce_array (arg1
);
590 if (TYPE_CODE (type
) == TYPE_CODE_FUNC
)
591 return value_coerce_function (arg1
);
593 if (VALUE_LVAL (arg1
) != lval_memory
)
594 error ("Attempt to take address of value not located in memory.");
596 return value_from_longest (lookup_pointer_type (type
),
597 (LONGEST
) (VALUE_ADDRESS (arg1
) + VALUE_OFFSET (arg1
)));
600 /* Given a value of a pointer type, apply the C unary * operator to it. */
608 if (TYPE_CODE (VALUE_TYPE (arg1
)) == TYPE_CODE_MEMBER
)
609 error ("not implemented: member types in value_ind");
611 /* Allow * on an integer so we can cast it to whatever we want.
612 This returns an int, which seems like the most C-like thing
613 to do. "long long" variables are rare enough that
614 BUILTIN_TYPE_LONGEST would seem to be a mistake. */
615 if (TYPE_CODE (VALUE_TYPE (arg1
)) == TYPE_CODE_INT
)
616 return value_at (builtin_type_int
,
617 (CORE_ADDR
) value_as_long (arg1
));
618 else if (TYPE_CODE (VALUE_TYPE (arg1
)) == TYPE_CODE_PTR
)
619 return value_at_lazy (TYPE_TARGET_TYPE (VALUE_TYPE (arg1
)),
620 value_as_pointer (arg1
));
621 error ("Attempt to take contents of a non-pointer value.");
622 return 0; /* For lint -- never reached */
625 /* Pushing small parts of stack frames. */
627 /* Push one word (the size of object that a register holds). */
634 register int len
= sizeof (REGISTER_TYPE
);
635 REGISTER_TYPE buffer
;
637 store_unsigned_integer (&buffer
, len
, word
);
640 write_memory (sp
, (char *)&buffer
, len
);
641 #else /* stack grows upward */
642 write_memory (sp
, (char *)&buffer
, len
);
644 #endif /* stack grows upward */
649 /* Push LEN bytes with data at BUFFER. */
652 push_bytes (sp
, buffer
, len
)
659 write_memory (sp
, buffer
, len
);
660 #else /* stack grows upward */
661 write_memory (sp
, buffer
, len
);
663 #endif /* stack grows upward */
668 /* Push onto the stack the specified value VALUE. */
672 register CORE_ADDR sp
;
675 register int len
= TYPE_LENGTH (VALUE_TYPE (arg
));
679 write_memory (sp
, VALUE_CONTENTS (arg
), len
);
680 #else /* stack grows upward */
681 write_memory (sp
, VALUE_CONTENTS (arg
), len
);
683 #endif /* stack grows upward */
688 /* Perform the standard coercions that are specified
689 for arguments to be passed to C functions. */
692 value_arg_coerce (arg
)
695 register struct type
*type
;
698 #if 1 /* FIXME: This is only a temporary patch. -fnf */
699 if (VALUE_REPEATED (arg
)
700 || TYPE_CODE (VALUE_TYPE (arg
)) == TYPE_CODE_ARRAY
)
701 arg
= value_coerce_array (arg
);
702 if (TYPE_CODE (VALUE_TYPE (arg
)) == TYPE_CODE_FUNC
)
703 arg
= value_coerce_function (arg
);
706 type
= VALUE_TYPE (arg
);
708 if (TYPE_CODE (type
) == TYPE_CODE_INT
709 && TYPE_LENGTH (type
) < TYPE_LENGTH (builtin_type_int
))
710 return value_cast (builtin_type_int
, arg
);
712 if (TYPE_CODE (type
) == TYPE_CODE_FLT
713 && TYPE_LENGTH (type
) < TYPE_LENGTH (builtin_type_double
))
714 return value_cast (builtin_type_double
, arg
);
719 /* Push the value ARG, first coercing it as an argument
723 value_arg_push (sp
, arg
)
724 register CORE_ADDR sp
;
727 return value_push (sp
, value_arg_coerce (arg
));
730 /* Determine a function's address and its return type from its value.
731 Calls error() if the function is not valid for calling. */
734 find_function_addr (function
, retval_type
)
736 struct type
**retval_type
;
738 register struct type
*ftype
= VALUE_TYPE (function
);
739 register enum type_code code
= TYPE_CODE (ftype
);
740 struct type
*value_type
;
743 /* If it's a member function, just look at the function
746 /* Determine address to call. */
747 if (code
== TYPE_CODE_FUNC
|| code
== TYPE_CODE_METHOD
)
749 funaddr
= VALUE_ADDRESS (function
);
750 value_type
= TYPE_TARGET_TYPE (ftype
);
752 else if (code
== TYPE_CODE_PTR
)
754 funaddr
= value_as_pointer (function
);
755 if (TYPE_CODE (TYPE_TARGET_TYPE (ftype
)) == TYPE_CODE_FUNC
756 || TYPE_CODE (TYPE_TARGET_TYPE (ftype
)) == TYPE_CODE_METHOD
)
757 value_type
= TYPE_TARGET_TYPE (TYPE_TARGET_TYPE (ftype
));
759 value_type
= builtin_type_int
;
761 else if (code
== TYPE_CODE_INT
)
763 /* Handle the case of functions lacking debugging info.
764 Their values are characters since their addresses are char */
765 if (TYPE_LENGTH (ftype
) == 1)
766 funaddr
= value_as_pointer (value_addr (function
));
768 /* Handle integer used as address of a function. */
769 funaddr
= (CORE_ADDR
) value_as_long (function
);
771 value_type
= builtin_type_int
;
774 error ("Invalid data type for function to be called.");
776 *retval_type
= value_type
;
780 #if defined (CALL_DUMMY)
781 /* All this stuff with a dummy frame may seem unnecessarily complicated
782 (why not just save registers in GDB?). The purpose of pushing a dummy
783 frame which looks just like a real frame is so that if you call a
784 function and then hit a breakpoint (get a signal, etc), "backtrace"
785 will look right. Whether the backtrace needs to actually show the
786 stack at the time the inferior function was called is debatable, but
787 it certainly needs to not display garbage. So if you are contemplating
788 making dummy frames be different from normal frames, consider that. */
790 /* Perform a function call in the inferior.
791 ARGS is a vector of values of arguments (NARGS of them).
792 FUNCTION is a value, the function to be called.
793 Returns a value representing what the function returned.
794 May fail to return, if a breakpoint or signal is hit
795 during the execution of the function. */
798 call_function_by_hand (function
, nargs
, args
)
803 register CORE_ADDR sp
;
806 /* CALL_DUMMY is an array of words (REGISTER_TYPE), but each word
807 is in host byte order. It is switched to target byte order before calling
809 static REGISTER_TYPE dummy
[] = CALL_DUMMY
;
810 REGISTER_TYPE dummy1
[sizeof dummy
/ sizeof (REGISTER_TYPE
)];
812 struct type
*value_type
;
813 unsigned char struct_return
;
814 CORE_ADDR struct_addr
;
815 struct inferior_status inf_status
;
816 struct cleanup
*old_chain
;
821 if (!target_has_execution
)
824 save_inferior_status (&inf_status
, 1);
825 old_chain
= make_cleanup (restore_inferior_status
, &inf_status
);
827 /* PUSH_DUMMY_FRAME is responsible for saving the inferior registers
828 (and POP_FRAME for restoring them). (At least on most machines)
829 they are saved on the stack in the inferior. */
832 old_sp
= sp
= read_sp ();
834 #if 1 INNER_THAN 2 /* Stack grows down */
837 #else /* Stack grows up */
842 funaddr
= find_function_addr (function
, &value_type
);
845 struct block
*b
= block_for_pc (funaddr
);
846 /* If compiled without -g, assume GCC. */
847 using_gcc
= b
== NULL
|| BLOCK_GCC_COMPILED (b
);
850 /* Are we returning a value using a structure return or a normal
853 struct_return
= using_struct_return (function
, funaddr
, value_type
,
856 /* Create a call sequence customized for this function
857 and the number of arguments for it. */
858 for (i
= 0; i
< sizeof dummy
/ sizeof (REGISTER_TYPE
); i
++)
859 store_unsigned_integer (&dummy1
[i
], sizeof (REGISTER_TYPE
),
860 (unsigned LONGEST
)dummy
[i
]);
862 #ifdef GDB_TARGET_IS_HPPA
863 real_pc
= FIX_CALL_DUMMY (dummy1
, start_sp
, funaddr
, nargs
, args
,
864 value_type
, using_gcc
);
866 FIX_CALL_DUMMY (dummy1
, start_sp
, funaddr
, nargs
, args
,
867 value_type
, using_gcc
);
871 #if CALL_DUMMY_LOCATION == ON_STACK
872 write_memory (start_sp
, (char *)dummy1
, sizeof dummy
);
874 #else /* Not on stack. */
875 #if CALL_DUMMY_LOCATION == BEFORE_TEXT_END
876 /* Convex Unix prohibits executing in the stack segment. */
877 /* Hope there is empty room at the top of the text segment. */
879 extern CORE_ADDR text_end
;
882 for (start_sp
= text_end
- sizeof dummy
; start_sp
< text_end
; ++start_sp
)
883 if (read_memory_integer (start_sp
, 1) != 0)
884 error ("text segment full -- no place to put call");
887 start_sp
= text_end
- sizeof dummy
;
888 write_memory (start_sp
, (char *)dummy1
, sizeof dummy
);
890 #else /* After text_end. */
892 extern CORE_ADDR text_end
;
896 errcode
= target_write_memory (start_sp
, (char *)dummy1
, sizeof dummy
);
898 error ("Cannot write text segment -- call_function failed");
900 #endif /* After text_end. */
901 #endif /* Not on stack. */
904 sp
= old_sp
; /* It really is used, for some ifdef's... */
908 /* If stack grows down, we must leave a hole at the top. */
912 /* Reserve space for the return structure to be written on the
913 stack, if necessary */
916 len
+= TYPE_LENGTH (value_type
);
918 for (i
= nargs
- 1; i
>= 0; i
--)
919 len
+= TYPE_LENGTH (VALUE_TYPE (value_arg_coerce (args
[i
])));
920 #ifdef CALL_DUMMY_STACK_ADJUST
921 len
+= CALL_DUMMY_STACK_ADJUST
;
924 sp
-= STACK_ALIGN (len
) - len
;
926 sp
+= STACK_ALIGN (len
) - len
;
929 #endif /* STACK_ALIGN */
931 /* Reserve space for the return structure to be written on the
932 stack, if necessary */
937 sp
-= TYPE_LENGTH (value_type
);
941 sp
+= TYPE_LENGTH (value_type
);
945 #if defined (REG_STRUCT_HAS_ADDR)
947 /* This is a machine like the sparc, where we need to pass a pointer
948 to the structure, not the structure itself. */
949 if (REG_STRUCT_HAS_ADDR (using_gcc
))
950 for (i
= nargs
- 1; i
>= 0; i
--)
951 if (TYPE_CODE (VALUE_TYPE (args
[i
])) == TYPE_CODE_STRUCT
)
954 #if !(1 INNER_THAN 2)
955 /* The stack grows up, so the address of the thing we push
956 is the stack pointer before we push it. */
959 /* Push the structure. */
960 sp
= value_push (sp
, args
[i
]);
962 /* The stack grows down, so the address of the thing we push
963 is the stack pointer after we push it. */
966 /* The value we're going to pass is the address of the thing
968 args
[i
] = value_from_longest (lookup_pointer_type (value_type
),
972 #endif /* REG_STRUCT_HAS_ADDR. */
974 #ifdef PUSH_ARGUMENTS
975 PUSH_ARGUMENTS(nargs
, args
, sp
, struct_return
, struct_addr
);
976 #else /* !PUSH_ARGUMENTS */
977 for (i
= nargs
- 1; i
>= 0; i
--)
978 sp
= value_arg_push (sp
, args
[i
]);
979 #endif /* !PUSH_ARGUMENTS */
981 #ifdef CALL_DUMMY_STACK_ADJUST
983 sp
-= CALL_DUMMY_STACK_ADJUST
;
985 sp
+= CALL_DUMMY_STACK_ADJUST
;
987 #endif /* CALL_DUMMY_STACK_ADJUST */
989 /* Store the address at which the structure is supposed to be
990 written. Note that this (and the code which reserved the space
991 above) assumes that gcc was used to compile this function. Since
992 it doesn't cost us anything but space and if the function is pcc
993 it will ignore this value, we will make that assumption.
995 Also note that on some machines (like the sparc) pcc uses a
996 convention like gcc's. */
999 STORE_STRUCT_RETURN (struct_addr
, sp
);
1001 /* Write the stack pointer. This is here because the statements above
1002 might fool with it. On SPARC, this write also stores the register
1003 window into the right place in the new stack frame, which otherwise
1004 wouldn't happen. (See store_inferior_registers in sparc-nat.c.) */
1007 /* Figure out the value returned by the function. */
1009 char retbuf
[REGISTER_BYTES
];
1011 struct symbol
*symbol
;
1014 symbol
= find_pc_function (funaddr
);
1017 name
= SYMBOL_SOURCE_NAME (symbol
);
1021 /* Try the minimal symbols. */
1022 struct minimal_symbol
*msymbol
= lookup_minimal_symbol_by_pc (funaddr
);
1026 name
= SYMBOL_SOURCE_NAME (msymbol
);
1032 sprintf (format
, "at %s", local_hex_format ());
1034 sprintf (name
, format
, funaddr
);
1037 /* Execute the stack dummy routine, calling FUNCTION.
1038 When it is done, discard the empty frame
1039 after storing the contents of all regs into retbuf. */
1040 run_stack_dummy (name
, real_pc
+ CALL_DUMMY_START_OFFSET
, retbuf
);
1042 do_cleanups (old_chain
);
1044 return value_being_returned (value_type
, retbuf
, struct_return
);
1047 #else /* no CALL_DUMMY. */
1049 call_function_by_hand (function
, nargs
, args
)
1054 error ("Cannot invoke functions on this machine.");
1056 #endif /* no CALL_DUMMY. */
1059 /* Create a value for an array by allocating space in the inferior, copying
1060 the data into that space, and then setting up an array value.
1062 The array bounds are set from LOWBOUND and HIGHBOUND, and the array is
1063 populated from the values passed in ELEMVEC.
1065 The element type of the array is inherited from the type of the
1066 first element, and all elements must have the same size (though we
1067 don't currently enforce any restriction on their types). */
1070 value_array (lowbound
, highbound
, elemvec
)
1079 struct type
*rangetype
;
1080 struct type
*arraytype
;
1083 /* Validate that the bounds are reasonable and that each of the elements
1084 have the same size. */
1086 nelem
= highbound
- lowbound
+ 1;
1089 error ("bad array bounds (%d, %d)", lowbound
, highbound
);
1091 typelength
= TYPE_LENGTH (VALUE_TYPE (elemvec
[0]));
1092 for (idx
= 0; idx
< nelem
; idx
++)
1094 if (TYPE_LENGTH (VALUE_TYPE (elemvec
[idx
])) != typelength
)
1096 error ("array elements must all be the same size");
1100 /* Allocate space to store the array in the inferior, and then initialize
1101 it by copying in each element. FIXME: Is it worth it to create a
1102 local buffer in which to collect each value and then write all the
1103 bytes in one operation? */
1105 addr
= allocate_space_in_inferior (nelem
* typelength
);
1106 for (idx
= 0; idx
< nelem
; idx
++)
1108 write_memory (addr
+ (idx
* typelength
), VALUE_CONTENTS (elemvec
[idx
]),
1112 /* Create the array type and set up an array value to be evaluated lazily. */
1114 rangetype
= create_range_type ((struct type
*) NULL
, builtin_type_int
,
1115 lowbound
, highbound
);
1116 arraytype
= create_array_type ((struct type
*) NULL
,
1117 VALUE_TYPE (elemvec
[0]), rangetype
);
1118 val
= value_at_lazy (arraytype
, addr
);
1122 /* Create a value for a string constant by allocating space in the inferior,
1123 copying the data into that space, and returning the address with type
1124 TYPE_CODE_STRING. PTR points to the string constant data; LEN is number
1126 Note that string types are like array of char types with a lower bound of
1127 zero and an upper bound of LEN - 1. Also note that the string may contain
1128 embedded null bytes. */
1131 value_string (ptr
, len
)
1136 struct type
*rangetype
;
1137 struct type
*stringtype
;
1140 /* Allocate space to store the string in the inferior, and then
1141 copy LEN bytes from PTR in gdb to that address in the inferior. */
1143 addr
= allocate_space_in_inferior (len
);
1144 write_memory (addr
, ptr
, len
);
1146 /* Create the string type and set up a string value to be evaluated
1149 rangetype
= create_range_type ((struct type
*) NULL
, builtin_type_int
,
1151 stringtype
= create_string_type ((struct type
*) NULL
, rangetype
);
1152 val
= value_at_lazy (stringtype
, addr
);
1156 /* Compare two argument lists and return the position in which they differ,
1159 STATICP is nonzero if the T1 argument list came from a
1160 static member function.
1162 For non-static member functions, we ignore the first argument,
1163 which is the type of the instance variable. This is because we want
1164 to handle calls with objects from derived classes. This is not
1165 entirely correct: we should actually check to make sure that a
1166 requested operation is type secure, shouldn't we? FIXME. */
1169 typecmp (staticp
, t1
, t2
)
1178 if (staticp
&& t1
== 0)
1182 if (TYPE_CODE (t1
[0]) == TYPE_CODE_VOID
) return 0;
1183 if (t1
[!staticp
] == 0) return 0;
1184 for (i
= !staticp
; t1
[i
] && TYPE_CODE (t1
[i
]) != TYPE_CODE_VOID
; i
++)
1188 if (TYPE_CODE (t1
[i
]) == TYPE_CODE_REF
1189 && TYPE_TARGET_TYPE (t1
[i
]) == VALUE_TYPE (t2
[i
]))
1191 if (TYPE_CODE (t1
[i
]) != TYPE_CODE (VALUE_TYPE (t2
[i
])))
1194 if (!t1
[i
]) return 0;
1195 return t2
[i
] ? i
+1 : 0;
1198 /* Helper function used by value_struct_elt to recurse through baseclasses.
1199 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
1200 and search in it assuming it has (class) type TYPE.
1201 If found, return value, else return NULL.
1203 If LOOKING_FOR_BASECLASS, then instead of looking for struct fields,
1204 look for a baseclass named NAME. */
1207 search_struct_field (name
, arg1
, offset
, type
, looking_for_baseclass
)
1209 register value arg1
;
1211 register struct type
*type
;
1212 int looking_for_baseclass
;
1216 check_stub_type (type
);
1218 if (! looking_for_baseclass
)
1219 for (i
= TYPE_NFIELDS (type
) - 1; i
>= TYPE_N_BASECLASSES (type
); i
--)
1221 char *t_field_name
= TYPE_FIELD_NAME (type
, i
);
1223 if (t_field_name
&& STREQ (t_field_name
, name
))
1226 if (TYPE_FIELD_STATIC (type
, i
))
1228 char *phys_name
= TYPE_FIELD_STATIC_PHYSNAME (type
, i
);
1229 struct symbol
*sym
=
1230 lookup_symbol (phys_name
, 0, VAR_NAMESPACE
, 0, NULL
);
1232 error ("Internal error: could not find physical static variable named %s",
1234 v
= value_at (TYPE_FIELD_TYPE (type
, i
),
1235 (CORE_ADDR
)SYMBOL_BLOCK_VALUE (sym
));
1238 v
= value_primitive_field (arg1
, offset
, i
, type
);
1240 error("there is no field named %s", name
);
1245 for (i
= TYPE_N_BASECLASSES (type
) - 1; i
>= 0; i
--)
1248 /* If we are looking for baseclasses, this is what we get when we
1249 hit them. But it could happen that the base part's member name
1250 is not yet filled in. */
1251 int found_baseclass
= (looking_for_baseclass
1252 && TYPE_BASECLASS_NAME (type
, i
) != NULL
1253 && STREQ (name
, TYPE_BASECLASS_NAME (type
, i
)));
1255 if (BASETYPE_VIA_VIRTUAL (type
, i
))
1258 /* Fix to use baseclass_offset instead. FIXME */
1259 baseclass_addr (type
, i
, VALUE_CONTENTS (arg1
) + offset
,
1262 error ("virtual baseclass botch");
1263 if (found_baseclass
)
1265 v
= search_struct_field (name
, v2
, 0, TYPE_BASECLASS (type
, i
),
1266 looking_for_baseclass
);
1268 else if (found_baseclass
)
1269 v
= value_primitive_field (arg1
, offset
, i
, type
);
1271 v
= search_struct_field (name
, arg1
,
1272 offset
+ TYPE_BASECLASS_BITPOS (type
, i
) / 8,
1273 TYPE_BASECLASS (type
, i
),
1274 looking_for_baseclass
);
1280 /* Helper function used by value_struct_elt to recurse through baseclasses.
1281 Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
1282 and search in it assuming it has (class) type TYPE.
1283 If found, return value, else return NULL. */
1286 search_struct_method (name
, arg1p
, args
, offset
, static_memfuncp
, type
)
1288 register value
*arg1p
, *args
;
1289 int offset
, *static_memfuncp
;
1290 register struct type
*type
;
1294 check_stub_type (type
);
1295 for (i
= TYPE_NFN_FIELDS (type
) - 1; i
>= 0; i
--)
1297 char *t_field_name
= TYPE_FN_FIELDLIST_NAME (type
, i
);
1298 if (t_field_name
&& STREQ (t_field_name
, name
))
1300 int j
= TYPE_FN_FIELDLIST_LENGTH (type
, i
) - 1;
1301 struct fn_field
*f
= TYPE_FN_FIELDLIST1 (type
, i
);
1303 if (j
> 0 && args
== 0)
1304 error ("cannot resolve overloaded method `%s'", name
);
1307 if (TYPE_FN_FIELD_STUB (f
, j
))
1308 check_stub_method (type
, i
, j
);
1309 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f
, j
),
1310 TYPE_FN_FIELD_ARGS (f
, j
), args
))
1312 if (TYPE_FN_FIELD_VIRTUAL_P (f
, j
))
1313 return (value
)value_virtual_fn_field (arg1p
, f
, j
, type
, offset
);
1314 if (TYPE_FN_FIELD_STATIC_P (f
, j
) && static_memfuncp
)
1315 *static_memfuncp
= 1;
1316 return (value
)value_fn_field (arg1p
, f
, j
, type
, offset
);
1323 for (i
= TYPE_N_BASECLASSES (type
) - 1; i
>= 0; i
--)
1328 if (BASETYPE_VIA_VIRTUAL (type
, i
))
1330 base_offset
= baseclass_offset (type
, i
, *arg1p
, offset
);
1331 if (base_offset
== -1)
1332 error ("virtual baseclass botch");
1336 base_offset
= TYPE_BASECLASS_BITPOS (type
, i
) / 8;
1338 v
= search_struct_method (name
, arg1p
, args
, base_offset
+ offset
,
1339 static_memfuncp
, TYPE_BASECLASS (type
, i
));
1342 /* FIXME-bothner: Why is this commented out? Why is it here? */
1343 /* *arg1p = arg1_tmp;*/
1350 /* Given *ARGP, a value of type (pointer to a)* structure/union,
1351 extract the component named NAME from the ultimate target structure/union
1352 and return it as a value with its appropriate type.
1353 ERR is used in the error message if *ARGP's type is wrong.
1355 C++: ARGS is a list of argument types to aid in the selection of
1356 an appropriate method. Also, handle derived types.
1358 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
1359 where the truthvalue of whether the function that was resolved was
1360 a static member function or not is stored.
1362 ERR is an error message to be printed in case the field is not found. */
1365 value_struct_elt (argp
, args
, name
, static_memfuncp
, err
)
1366 register value
*argp
, *args
;
1368 int *static_memfuncp
;
1371 register struct type
*t
;
1374 COERCE_ARRAY (*argp
);
1376 t
= VALUE_TYPE (*argp
);
1378 /* Follow pointers until we get to a non-pointer. */
1380 while (TYPE_CODE (t
) == TYPE_CODE_PTR
|| TYPE_CODE (t
) == TYPE_CODE_REF
)
1382 *argp
= value_ind (*argp
);
1383 /* Don't coerce fn pointer to fn and then back again! */
1384 if (TYPE_CODE (VALUE_TYPE (*argp
)) != TYPE_CODE_FUNC
)
1385 COERCE_ARRAY (*argp
);
1386 t
= VALUE_TYPE (*argp
);
1389 if (TYPE_CODE (t
) == TYPE_CODE_MEMBER
)
1390 error ("not implemented: member type in value_struct_elt");
1392 if ( TYPE_CODE (t
) != TYPE_CODE_STRUCT
1393 && TYPE_CODE (t
) != TYPE_CODE_UNION
)
1394 error ("Attempt to extract a component of a value that is not a %s.", err
);
1396 /* Assume it's not, unless we see that it is. */
1397 if (static_memfuncp
)
1398 *static_memfuncp
=0;
1402 /* if there are no arguments ...do this... */
1404 /* Try as a field first, because if we succeed, there
1405 is less work to be done. */
1406 v
= search_struct_field (name
, *argp
, 0, t
, 0);
1410 /* C++: If it was not found as a data field, then try to
1411 return it as a pointer to a method. */
1413 if (destructor_name_p (name
, t
))
1414 error ("Cannot get value of destructor");
1416 v
= search_struct_method (name
, argp
, args
, 0, static_memfuncp
, t
);
1420 if (TYPE_NFN_FIELDS (t
))
1421 error ("There is no member or method named %s.", name
);
1423 error ("There is no member named %s.", name
);
1428 if (destructor_name_p (name
, t
))
1432 /* destructors are a special case. */
1433 return (value
)value_fn_field (NULL
, TYPE_FN_FIELDLIST1 (t
, 0),
1434 TYPE_FN_FIELDLIST_LENGTH (t
, 0),
1439 error ("destructor should not have any argument");
1443 v
= search_struct_method (name
, argp
, args
, 0, static_memfuncp
, t
);
1447 /* See if user tried to invoke data as function. If so,
1448 hand it back. If it's not callable (i.e., a pointer to function),
1449 gdb should give an error. */
1450 v
= search_struct_field (name
, *argp
, 0, t
, 0);
1454 error ("Structure has no component named %s.", name
);
1458 /* C++: return 1 is NAME is a legitimate name for the destructor
1459 of type TYPE. If TYPE does not have a destructor, or
1460 if NAME is inappropriate for TYPE, an error is signaled. */
1462 destructor_name_p (name
, type
)
1464 const struct type
*type
;
1466 /* destructors are a special case. */
1470 char *dname
= type_name_no_tag (type
);
1471 if (!STREQ (dname
, name
+1))
1472 error ("name of destructor must equal name of class");
1479 /* Helper function for check_field: Given TYPE, a structure/union,
1480 return 1 if the component named NAME from the ultimate
1481 target structure/union is defined, otherwise, return 0. */
1484 check_field_in (type
, name
)
1485 register struct type
*type
;
1490 for (i
= TYPE_NFIELDS (type
) - 1; i
>= TYPE_N_BASECLASSES (type
); i
--)
1492 char *t_field_name
= TYPE_FIELD_NAME (type
, i
);
1493 if (t_field_name
&& STREQ (t_field_name
, name
))
1497 /* C++: If it was not found as a data field, then try to
1498 return it as a pointer to a method. */
1500 /* Destructors are a special case. */
1501 if (destructor_name_p (name
, type
))
1504 for (i
= TYPE_NFN_FIELDS (type
) - 1; i
>= 0; --i
)
1506 if (STREQ (TYPE_FN_FIELDLIST_NAME (type
, i
), name
))
1510 for (i
= TYPE_N_BASECLASSES (type
) - 1; i
>= 0; i
--)
1511 if (check_field_in (TYPE_BASECLASS (type
, i
), name
))
1518 /* C++: Given ARG1, a value of type (pointer to a)* structure/union,
1519 return 1 if the component named NAME from the ultimate
1520 target structure/union is defined, otherwise, return 0. */
1523 check_field (arg1
, name
)
1524 register value arg1
;
1527 register struct type
*t
;
1529 COERCE_ARRAY (arg1
);
1531 t
= VALUE_TYPE (arg1
);
1533 /* Follow pointers until we get to a non-pointer. */
1535 while (TYPE_CODE (t
) == TYPE_CODE_PTR
|| TYPE_CODE (t
) == TYPE_CODE_REF
)
1536 t
= TYPE_TARGET_TYPE (t
);
1538 if (TYPE_CODE (t
) == TYPE_CODE_MEMBER
)
1539 error ("not implemented: member type in check_field");
1541 if ( TYPE_CODE (t
) != TYPE_CODE_STRUCT
1542 && TYPE_CODE (t
) != TYPE_CODE_UNION
)
1543 error ("Internal error: `this' is not an aggregate");
1545 return check_field_in (t
, name
);
1548 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
1549 return the address of this member as a "pointer to member"
1550 type. If INTYPE is non-null, then it will be the type
1551 of the member we are looking for. This will help us resolve
1552 "pointers to member functions". This function is used
1553 to resolve user expressions of the form "DOMAIN::NAME". */
1556 value_struct_elt_for_reference (domain
, offset
, curtype
, name
, intype
)
1557 struct type
*domain
, *curtype
, *intype
;
1561 register struct type
*t
= curtype
;
1565 if ( TYPE_CODE (t
) != TYPE_CODE_STRUCT
1566 && TYPE_CODE (t
) != TYPE_CODE_UNION
)
1567 error ("Internal error: non-aggregate type to value_struct_elt_for_reference");
1569 for (i
= TYPE_NFIELDS (t
) - 1; i
>= TYPE_N_BASECLASSES (t
); i
--)
1571 char *t_field_name
= TYPE_FIELD_NAME (t
, i
);
1573 if (t_field_name
&& STREQ (t_field_name
, name
))
1575 if (TYPE_FIELD_STATIC (t
, i
))
1577 char *phys_name
= TYPE_FIELD_STATIC_PHYSNAME (t
, i
);
1578 struct symbol
*sym
=
1579 lookup_symbol (phys_name
, 0, VAR_NAMESPACE
, 0, NULL
);
1581 error ("Internal error: could not find physical static variable named %s",
1583 return value_at (SYMBOL_TYPE (sym
),
1584 (CORE_ADDR
)SYMBOL_BLOCK_VALUE (sym
));
1586 if (TYPE_FIELD_PACKED (t
, i
))
1587 error ("pointers to bitfield members not allowed");
1589 return value_from_longest
1590 (lookup_reference_type (lookup_member_type (TYPE_FIELD_TYPE (t
, i
),
1592 offset
+ (LONGEST
) (TYPE_FIELD_BITPOS (t
, i
) >> 3));
1596 /* C++: If it was not found as a data field, then try to
1597 return it as a pointer to a method. */
1599 /* Destructors are a special case. */
1600 if (destructor_name_p (name
, t
))
1602 error ("member pointers to destructors not implemented yet");
1605 /* Perform all necessary dereferencing. */
1606 while (intype
&& TYPE_CODE (intype
) == TYPE_CODE_PTR
)
1607 intype
= TYPE_TARGET_TYPE (intype
);
1609 for (i
= TYPE_NFN_FIELDS (t
) - 1; i
>= 0; --i
)
1611 if (STREQ (TYPE_FN_FIELDLIST_NAME (t
, i
), name
))
1613 int j
= TYPE_FN_FIELDLIST_LENGTH (t
, i
);
1614 struct fn_field
*f
= TYPE_FN_FIELDLIST1 (t
, i
);
1616 if (intype
== 0 && j
> 1)
1617 error ("non-unique member `%s' requires type instantiation", name
);
1621 if (TYPE_FN_FIELD_TYPE (f
, j
) == intype
)
1624 error ("no member function matches that type instantiation");
1629 if (TYPE_FN_FIELD_STUB (f
, j
))
1630 check_stub_method (t
, i
, j
);
1631 if (TYPE_FN_FIELD_VIRTUAL_P (f
, j
))
1633 return value_from_longest
1634 (lookup_reference_type
1635 (lookup_member_type (TYPE_FN_FIELD_TYPE (f
, j
),
1637 (LONGEST
) METHOD_PTR_FROM_VOFFSET
1638 (TYPE_FN_FIELD_VOFFSET (f
, j
)));
1642 struct symbol
*s
= lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f
, j
),
1643 0, VAR_NAMESPACE
, 0, NULL
);
1650 v
= read_var_value (s
, 0);
1652 VALUE_TYPE (v
) = lookup_reference_type
1653 (lookup_member_type (TYPE_FN_FIELD_TYPE (f
, j
),
1661 for (i
= TYPE_N_BASECLASSES (t
) - 1; i
>= 0; i
--)
1666 if (BASETYPE_VIA_VIRTUAL (t
, i
))
1669 base_offset
= TYPE_BASECLASS_BITPOS (t
, i
) / 8;
1670 v
= value_struct_elt_for_reference (domain
,
1671 offset
+ base_offset
,
1672 TYPE_BASECLASS (t
, i
),
1681 /* C++: return the value of the class instance variable, if one exists.
1682 Flag COMPLAIN signals an error if the request is made in an
1683 inappropriate context. */
1685 value_of_this (complain
)
1688 extern FRAME selected_frame
;
1689 struct symbol
*func
, *sym
;
1692 static const char funny_this
[] = "this";
1695 if (selected_frame
== 0)
1697 error ("no frame selected");
1700 func
= get_frame_function (selected_frame
);
1704 error ("no `this' in nameless context");
1708 b
= SYMBOL_BLOCK_VALUE (func
);
1709 i
= BLOCK_NSYMS (b
);
1712 error ("no args, no `this'");
1715 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
1716 symbol instead of the LOC_ARG one (if both exist). */
1717 sym
= lookup_block_symbol (b
, funny_this
, VAR_NAMESPACE
);
1721 error ("current stack frame not in method");
1726 this = read_var_value (sym
, selected_frame
);
1727 if (this == 0 && complain
)
1728 error ("`this' argument at unknown address");