1 /* Perform an inferior function call, for GDB, the GNU debugger.
3 Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
4 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Free Software
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
25 #include "breakpoint.h"
29 #include "gdb_assert.h"
36 #include "gdb_string.h"
38 /* NOTE: cagney/2003-04-16: What's the future of this code?
40 GDB needs an asynchronous expression evaluator, that means an
41 asynchronous inferior function call implementation, and that in
42 turn means restructuring the code so that it is event driven. */
44 /* How you should pass arguments to a function depends on whether it
45 was defined in K&R style or prototype style. If you define a
46 function using the K&R syntax that takes a `float' argument, then
47 callers must pass that argument as a `double'. If you define the
48 function using the prototype syntax, then you must pass the
49 argument as a `float', with no promotion.
51 Unfortunately, on certain older platforms, the debug info doesn't
52 indicate reliably how each function was defined. A function type's
53 TYPE_FLAG_PROTOTYPED flag may be clear, even if the function was
54 defined in prototype style. When calling a function whose
55 TYPE_FLAG_PROTOTYPED flag is clear, GDB consults this flag to
58 For modern targets, it is proper to assume that, if the prototype
59 flag is clear, that can be trusted: `float' arguments should be
60 promoted to `double'. For some older targets, if the prototype
61 flag is clear, that doesn't tell us anything. The default is to
62 trust the debug information; the user can override this behavior
63 with "set coerce-float-to-double 0". */
65 static int coerce_float_to_double_p
= 1;
67 /* This boolean tells what gdb should do if a signal is received while
68 in a function called from gdb (call dummy). If set, gdb unwinds
69 the stack and restore the context to what as it was before the
72 The default is to stop in the frame where the signal was received. */
74 int unwind_on_signal_p
= 0;
76 /* Perform the standard coercions that are specified
77 for arguments to be passed to C functions.
79 If PARAM_TYPE is non-NULL, it is the expected parameter type.
80 IS_PROTOTYPED is non-zero if the function declaration is prototyped. */
83 value_arg_coerce (struct value
*arg
, struct type
*param_type
,
86 register struct type
*arg_type
= check_typedef (VALUE_TYPE (arg
));
87 register struct type
*type
88 = param_type
? check_typedef (param_type
) : arg_type
;
90 switch (TYPE_CODE (type
))
93 if (TYPE_CODE (arg_type
) != TYPE_CODE_REF
94 && TYPE_CODE (arg_type
) != TYPE_CODE_PTR
)
96 arg
= value_addr (arg
);
97 VALUE_TYPE (arg
) = param_type
;
105 /* If we don't have a prototype, coerce to integer type if necessary. */
108 if (TYPE_LENGTH (type
) < TYPE_LENGTH (builtin_type_int
))
109 type
= builtin_type_int
;
111 /* Currently all target ABIs require at least the width of an integer
112 type for an argument. We may have to conditionalize the following
113 type coercion for future targets. */
114 if (TYPE_LENGTH (type
) < TYPE_LENGTH (builtin_type_int
))
115 type
= builtin_type_int
;
118 if (!is_prototyped
&& coerce_float_to_double_p
)
120 if (TYPE_LENGTH (type
) < TYPE_LENGTH (builtin_type_double
))
121 type
= builtin_type_double
;
122 else if (TYPE_LENGTH (type
) > TYPE_LENGTH (builtin_type_double
))
123 type
= builtin_type_long_double
;
127 type
= lookup_pointer_type (type
);
129 case TYPE_CODE_ARRAY
:
130 /* Arrays are coerced to pointers to their first element, unless
131 they are vectors, in which case we want to leave them alone,
132 because they are passed by value. */
133 if (current_language
->c_style_arrays
)
134 if (!TYPE_VECTOR (type
))
135 type
= lookup_pointer_type (TYPE_TARGET_TYPE (type
));
137 case TYPE_CODE_UNDEF
:
139 case TYPE_CODE_STRUCT
:
140 case TYPE_CODE_UNION
:
143 case TYPE_CODE_RANGE
:
144 case TYPE_CODE_STRING
:
145 case TYPE_CODE_BITSTRING
:
146 case TYPE_CODE_ERROR
:
147 case TYPE_CODE_MEMBER
:
148 case TYPE_CODE_METHOD
:
149 case TYPE_CODE_COMPLEX
:
154 return value_cast (type
, arg
);
157 /* Determine a function's address and its return type from its value.
158 Calls error() if the function is not valid for calling. */
161 find_function_addr (struct value
*function
, struct type
**retval_type
)
163 register struct type
*ftype
= check_typedef (VALUE_TYPE (function
));
164 register enum type_code code
= TYPE_CODE (ftype
);
165 struct type
*value_type
;
168 /* If it's a member function, just look at the function
171 /* Determine address to call. */
172 if (code
== TYPE_CODE_FUNC
|| code
== TYPE_CODE_METHOD
)
174 funaddr
= VALUE_ADDRESS (function
);
175 value_type
= TYPE_TARGET_TYPE (ftype
);
177 else if (code
== TYPE_CODE_PTR
)
179 funaddr
= value_as_address (function
);
180 ftype
= check_typedef (TYPE_TARGET_TYPE (ftype
));
181 if (TYPE_CODE (ftype
) == TYPE_CODE_FUNC
182 || TYPE_CODE (ftype
) == TYPE_CODE_METHOD
)
184 funaddr
= CONVERT_FROM_FUNC_PTR_ADDR (funaddr
);
185 value_type
= TYPE_TARGET_TYPE (ftype
);
188 value_type
= builtin_type_int
;
190 else if (code
== TYPE_CODE_INT
)
192 /* Handle the case of functions lacking debugging info.
193 Their values are characters since their addresses are char */
194 if (TYPE_LENGTH (ftype
) == 1)
195 funaddr
= value_as_address (value_addr (function
));
197 /* Handle integer used as address of a function. */
198 funaddr
= (CORE_ADDR
) value_as_long (function
);
200 value_type
= builtin_type_int
;
203 error ("Invalid data type for function to be called.");
205 *retval_type
= value_type
;
209 /* Call breakpoint_auto_delete on the current contents of the bpstat
210 pointed to by arg (which is really a bpstat *). */
213 breakpoint_auto_delete_contents (void *arg
)
215 breakpoint_auto_delete (*(bpstat
*) arg
);
218 /* All this stuff with a dummy frame may seem unnecessarily complicated
219 (why not just save registers in GDB?). The purpose of pushing a dummy
220 frame which looks just like a real frame is so that if you call a
221 function and then hit a breakpoint (get a signal, etc), "backtrace"
222 will look right. Whether the backtrace needs to actually show the
223 stack at the time the inferior function was called is debatable, but
224 it certainly needs to not display garbage. So if you are contemplating
225 making dummy frames be different from normal frames, consider that. */
227 /* Perform a function call in the inferior.
228 ARGS is a vector of values of arguments (NARGS of them).
229 FUNCTION is a value, the function to be called.
230 Returns a value representing what the function returned.
231 May fail to return, if a breakpoint or signal is hit
232 during the execution of the function.
234 ARGS is modified to contain coerced values. */
237 call_function_by_hand (struct value
*function
, int nargs
, struct value
**args
)
239 register CORE_ADDR sp
;
243 /* CALL_DUMMY is an array of words (REGISTER_SIZE), but each word
244 is in host byte order. Before calling FIX_CALL_DUMMY, we byteswap it
245 and remove any extra bytes which might exist because ULONGEST is
246 bigger than REGISTER_SIZE.
248 NOTE: This is pretty wierd, as the call dummy is actually a
249 sequence of instructions. But CISC machines will have
250 to pack the instructions into REGISTER_SIZE units (and
251 so will RISC machines for which INSTRUCTION_SIZE is not
254 NOTE: This is pretty stupid. CALL_DUMMY should be in strict
255 target byte order. */
257 static ULONGEST
*dummy
;
260 CORE_ADDR dummy_addr
;
262 struct type
*value_type
;
263 unsigned char struct_return
;
264 CORE_ADDR struct_addr
= 0;
265 struct regcache
*retbuf
;
266 struct cleanup
*retbuf_cleanup
;
267 struct inferior_status
*inf_status
;
268 struct cleanup
*inf_status_cleanup
;
270 int using_gcc
; /* Set to version of gcc in use, or zero if not gcc */
272 struct type
*param_type
= NULL
;
273 struct type
*ftype
= check_typedef (SYMBOL_TYPE (function
));
274 int n_method_args
= 0;
277 dummy
= alloca (SIZEOF_CALL_DUMMY_WORDS
);
278 sizeof_dummy1
= REGISTER_SIZE
* SIZEOF_CALL_DUMMY_WORDS
/ sizeof (ULONGEST
);
279 dummy1
= alloca (sizeof_dummy1
);
280 memcpy (dummy
, CALL_DUMMY_WORDS
, SIZEOF_CALL_DUMMY_WORDS
);
282 if (!target_has_execution
)
285 /* Create a cleanup chain that contains the retbuf (buffer
286 containing the register values). This chain is create BEFORE the
287 inf_status chain so that the inferior status can cleaned up
288 (restored or discarded) without having the retbuf freed. */
289 retbuf
= regcache_xmalloc (current_gdbarch
);
290 retbuf_cleanup
= make_cleanup_regcache_xfree (retbuf
);
292 /* A cleanup for the inferior status. Create this AFTER the retbuf
293 so that this can be discarded or applied without interfering with
295 inf_status
= save_inferior_status (1);
296 inf_status_cleanup
= make_cleanup_restore_inferior_status (inf_status
);
298 if (DEPRECATED_PUSH_DUMMY_FRAME_P ())
300 /* DEPRECATED_PUSH_DUMMY_FRAME is responsible for saving the
301 inferior registers (and frame_pop() for restoring them). (At
302 least on most machines) they are saved on the stack in the
304 DEPRECATED_PUSH_DUMMY_FRAME
;
308 /* FIXME: cagney/2003-02-26: Step zero of this little tinker is
309 to extract the generic dummy frame code from the architecture
310 vector. Hence this direct call.
312 A follow-on change is to modify this interface so that it takes
313 thread OR frame OR tpid as a parameter, and returns a dummy
314 frame handle. The handle can then be used further down as a
315 parameter SAVE_DUMMY_FRAME_TOS. Hmm, thinking about it, since
316 everything is ment to be using generic dummy frames, why not
317 even use some of the dummy frame code to here - do a regcache
318 dup and then pass the duped regcache, along with all the other
319 stuff, at one single point.
321 In fact, you can even save the structure's return address in the
322 dummy frame and fix one of those nasty lost struct return edge
324 generic_push_dummy_frame ();
329 /* Ensure that the initial SP is correctly aligned. */
330 if (gdbarch_frame_align_p (current_gdbarch
))
332 /* NOTE: cagney/2002-09-18:
334 On a RISC architecture, a void parameterless generic dummy
335 frame (i.e., no parameters, no result) typically does not
336 need to push anything the stack and hence can leave SP and
337 FP. Similarly, a framelss (possibly leaf) function does not
338 push anything on the stack and, hence, that too can leave FP
339 and SP unchanged. As a consequence, a sequence of void
340 parameterless generic dummy frame calls to frameless
341 functions will create a sequence of effectively identical
342 frames (SP, FP and TOS and PC the same). This, not
343 suprisingly, results in what appears to be a stack in an
344 infinite loop --- when GDB tries to find a generic dummy
345 frame on the internal dummy frame stack, it will always find
348 To avoid this problem, the code below always grows the stack.
349 That way, two dummy frames can never be identical. It does
350 burn a few bytes of stack but that is a small price to pay
352 sp
= gdbarch_frame_align (current_gdbarch
, old_sp
);
355 if (INNER_THAN (1, 2))
356 /* Stack grows down. */
357 sp
= gdbarch_frame_align (current_gdbarch
, old_sp
- 1);
359 /* Stack grows up. */
360 sp
= gdbarch_frame_align (current_gdbarch
, old_sp
+ 1);
362 gdb_assert ((INNER_THAN (1, 2) && sp
<= old_sp
)
363 || (INNER_THAN (2, 1) && sp
>= old_sp
));
366 /* FIXME: cagney/2002-09-18: Hey, you loose! Who knows how badly
367 aligned the SP is! Further, per comment above, if the generic
368 dummy frame ends up empty (because nothing is pushed) GDB won't
369 be able to correctly perform back traces. If a target is
370 having trouble with backtraces, first thing to do is add
371 FRAME_ALIGN() to its architecture vector. After that, try
372 adding SAVE_DUMMY_FRAME_TOS() and modifying
373 DEPRECATED_FRAME_CHAIN so that when the next outer frame is a
374 generic dummy, it returns the current frame's base. */
377 if (INNER_THAN (1, 2))
379 /* Stack grows down */
390 /* NOTE: cagney/2002-09-10: Don't bother re-adjusting the stack
391 after allocating space for the call dummy. A target can specify
392 a SIZEOF_DUMMY1 (via SIZEOF_CALL_DUMMY_WORDS) such that all local
393 alignment requirements are met. */
395 funaddr
= find_function_addr (function
, &value_type
);
396 CHECK_TYPEDEF (value_type
);
399 struct block
*b
= block_for_pc (funaddr
);
400 /* If compiled without -g, assume GCC 2. */
401 using_gcc
= (b
== NULL
? 2 : BLOCK_GCC_COMPILED (b
));
404 /* Are we returning a value using a structure return or a normal
407 struct_return
= using_struct_return (function
, funaddr
, value_type
,
410 /* Create a call sequence customized for this function
411 and the number of arguments for it. */
412 for (i
= 0; i
< (int) (SIZEOF_CALL_DUMMY_WORDS
/ sizeof (dummy
[0])); i
++)
413 store_unsigned_integer (&dummy1
[i
* REGISTER_SIZE
],
415 (ULONGEST
) dummy
[i
]);
417 switch (CALL_DUMMY_LOCATION
)
420 /* NOTE: cagney/2003-04-22: This computation of REAL_PC, BP_ADDR
421 and DUMMY_ADDR is pretty messed up. It comes from constant
422 tinkering with the values. Instead a FIX_CALL_DUMMY
423 replacement (PUSH_DUMMY_BREAKPOINT?) should just do
425 #ifdef GDB_TARGET_IS_HPPA
426 real_pc
= FIX_CALL_DUMMY (dummy1
, start_sp
, funaddr
, nargs
, args
,
427 value_type
, using_gcc
);
429 if (FIX_CALL_DUMMY_P ())
431 /* gdb_assert (CALL_DUMMY_LOCATION == ON_STACK) true? */
432 FIX_CALL_DUMMY (dummy1
, start_sp
, funaddr
, nargs
, args
, value_type
,
437 dummy_addr
= start_sp
;
438 /* Yes, the offset is applied to the real_pc and not the dummy
439 addr. Ulgh! Blame the HP/UX target. */
440 bp_addr
= real_pc
+ CALL_DUMMY_BREAKPOINT_OFFSET
;
441 /* Yes, the offset is applied to the real_pc and not the
442 dummy_addr. Ulgh! Blame the HP/UX target. */
443 real_pc
+= CALL_DUMMY_START_OFFSET
;
444 write_memory (start_sp
, (char *) dummy1
, sizeof_dummy1
);
445 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
)
446 generic_save_call_dummy_addr (start_sp
, start_sp
+ sizeof_dummy1
);
450 dummy_addr
= CALL_DUMMY_ADDRESS ();
451 /* A call dummy always consists of just a single breakpoint, so
452 it's address is the same as the address of the dummy. */
453 bp_addr
= dummy_addr
;
454 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
)
455 /* NOTE: cagney/2002-04-13: The entry point is going to be
456 modified with a single breakpoint. */
457 generic_save_call_dummy_addr (CALL_DUMMY_ADDRESS (),
458 CALL_DUMMY_ADDRESS () + 1);
461 internal_error (__FILE__
, __LINE__
, "bad switch");
465 sp
= old_sp
; /* It really is used, for some ifdef's... */
468 if (nargs
< TYPE_NFIELDS (ftype
))
469 error ("too few arguments in function call");
471 for (i
= nargs
- 1; i
>= 0; i
--)
475 /* FIXME drow/2002-05-31: Should just always mark methods as
476 prototyped. Can we respect TYPE_VARARGS? Probably not. */
477 if (TYPE_CODE (ftype
) == TYPE_CODE_METHOD
)
480 prototyped
= TYPE_PROTOTYPED (ftype
);
482 if (i
< TYPE_NFIELDS (ftype
))
483 args
[i
] = value_arg_coerce (args
[i
], TYPE_FIELD_TYPE (ftype
, i
),
486 args
[i
] = value_arg_coerce (args
[i
], NULL
, 0);
488 /*elz: this code is to handle the case in which the function to be called
489 has a pointer to function as parameter and the corresponding actual argument
490 is the address of a function and not a pointer to function variable.
491 In aCC compiled code, the calls through pointers to functions (in the body
492 of the function called by hand) are made via $$dyncall_external which
493 requires some registers setting, this is taken care of if we call
494 via a function pointer variable, but not via a function address.
495 In cc this is not a problem. */
498 if (param_type
&& TYPE_CODE (ftype
) != TYPE_CODE_METHOD
)
499 /* if this parameter is a pointer to function */
500 if (TYPE_CODE (param_type
) == TYPE_CODE_PTR
)
501 if (TYPE_CODE (TYPE_TARGET_TYPE (param_type
)) == TYPE_CODE_FUNC
)
502 /* elz: FIXME here should go the test about the compiler used
503 to compile the target. We want to issue the error
504 message only if the compiler used was HP's aCC.
505 If we used HP's cc, then there is no problem and no need
506 to return at this point */
507 if (using_gcc
== 0) /* && compiler == aCC */
508 /* go see if the actual parameter is a variable of type
509 pointer to function or just a function */
510 if (args
[i
]->lval
== not_lval
)
513 if (find_pc_partial_function ((CORE_ADDR
) args
[i
]->aligner
.contents
[0], &arg_name
, NULL
, NULL
))
515 You cannot use function <%s> as argument. \n\
516 You must use a pointer to function type variable. Command ignored.", arg_name
);
520 if (REG_STRUCT_HAS_ADDR_P ())
522 /* This is a machine like the sparc, where we may need to pass a
523 pointer to the structure, not the structure itself. */
524 for (i
= nargs
- 1; i
>= 0; i
--)
526 struct type
*arg_type
= check_typedef (VALUE_TYPE (args
[i
]));
527 if ((TYPE_CODE (arg_type
) == TYPE_CODE_STRUCT
528 || TYPE_CODE (arg_type
) == TYPE_CODE_UNION
529 || TYPE_CODE (arg_type
) == TYPE_CODE_ARRAY
530 || TYPE_CODE (arg_type
) == TYPE_CODE_STRING
531 || TYPE_CODE (arg_type
) == TYPE_CODE_BITSTRING
532 || TYPE_CODE (arg_type
) == TYPE_CODE_SET
533 || (TYPE_CODE (arg_type
) == TYPE_CODE_FLT
534 && TYPE_LENGTH (arg_type
) > 8)
536 && REG_STRUCT_HAS_ADDR (using_gcc
, arg_type
))
539 int len
; /* = TYPE_LENGTH (arg_type); */
541 arg_type
= check_typedef (VALUE_ENCLOSING_TYPE (args
[i
]));
542 len
= TYPE_LENGTH (arg_type
);
544 if (STACK_ALIGN_P ())
545 /* MVS 11/22/96: I think at least some of this
546 stack_align code is really broken. Better to let
547 PUSH_ARGUMENTS adjust the stack in a target-defined
549 aligned_len
= STACK_ALIGN (len
);
552 if (INNER_THAN (1, 2))
554 /* stack grows downward */
556 /* ... so the address of the thing we push is the
557 stack pointer after we push it. */
562 /* The stack grows up, so the address of the thing
563 we push is the stack pointer before we push it. */
567 /* Push the structure. */
568 write_memory (addr
, VALUE_CONTENTS_ALL (args
[i
]), len
);
569 /* The value we're going to pass is the address of the
570 thing we just pushed. */
571 /*args[i] = value_from_longest (lookup_pointer_type (value_type),
573 args
[i
] = value_from_pointer (lookup_pointer_type (arg_type
),
580 /* Reserve space for the return structure to be written on the
581 stack, if necessary. Make certain that the value is correctly
586 int len
= TYPE_LENGTH (value_type
);
587 if (STACK_ALIGN_P ())
588 /* NOTE: cagney/2003-03-22: Should rely on frame align, rather
589 than stack align to force the alignment of the stack. */
590 len
= STACK_ALIGN (len
);
591 if (INNER_THAN (1, 2))
593 /* Stack grows downward. Align STRUCT_ADDR and SP after
594 making space for the return value. */
596 if (gdbarch_frame_align_p (current_gdbarch
))
597 sp
= gdbarch_frame_align (current_gdbarch
, sp
);
602 /* Stack grows upward. Align the frame, allocate space, and
603 then again, re-align the frame??? */
604 if (gdbarch_frame_align_p (current_gdbarch
))
605 sp
= gdbarch_frame_align (current_gdbarch
, sp
);
608 if (gdbarch_frame_align_p (current_gdbarch
))
609 sp
= gdbarch_frame_align (current_gdbarch
, sp
);
613 /* elz: on HPPA no need for this extra alignment, maybe it is needed
614 on other architectures. This is because all the alignment is
615 taken care of in the above code (ifdef REG_STRUCT_HAS_ADDR) and
616 in hppa_push_arguments */
617 /* NOTE: cagney/2003-03-24: The below code is very broken. Given an
618 odd sized parameter the below will mis-align the stack. As was
619 suggested back in '96, better to let PUSH_ARGUMENTS handle it. */
620 if (DEPRECATED_EXTRA_STACK_ALIGNMENT_NEEDED
)
622 /* MVS 11/22/96: I think at least some of this stack_align code
623 is really broken. Better to let push_dummy_call() adjust the
624 stack in a target-defined manner. */
625 if (STACK_ALIGN_P () && INNER_THAN (1, 2))
627 /* If stack grows down, we must leave a hole at the top. */
630 for (i
= nargs
- 1; i
>= 0; i
--)
631 len
+= TYPE_LENGTH (VALUE_ENCLOSING_TYPE (args
[i
]));
632 if (DEPRECATED_CALL_DUMMY_STACK_ADJUST_P ())
633 len
+= DEPRECATED_CALL_DUMMY_STACK_ADJUST
;
634 sp
-= STACK_ALIGN (len
) - len
;
638 /* Create the dummy stack frame. Pass in the call dummy address as,
639 presumably, the ABI code knows where, in the call dummy, the
640 return address should be pointed. */
641 if (gdbarch_push_dummy_call_p (current_gdbarch
))
642 /* When there is no push_dummy_call method, should this code
643 simply error out. That would the implementation of this method
644 for all ABIs (which is probably a good thing). */
645 sp
= gdbarch_push_dummy_call (current_gdbarch
, current_regcache
,
646 dummy_addr
, nargs
, args
, sp
, struct_return
,
648 else if (DEPRECATED_PUSH_ARGUMENTS_P ())
649 /* Keep old targets working. */
650 sp
= DEPRECATED_PUSH_ARGUMENTS (nargs
, args
, sp
, struct_return
,
653 sp
= legacy_push_arguments (nargs
, args
, sp
, struct_return
, struct_addr
);
655 if (DEPRECATED_PUSH_RETURN_ADDRESS_P ())
656 /* for targets that use no CALL_DUMMY */
657 /* There are a number of targets now which actually don't write
658 any CALL_DUMMY instructions into the target, but instead just
659 save the machine state, push the arguments, and jump directly
660 to the callee function. Since this doesn't actually involve
661 executing a JSR/BSR instruction, the return address must be set
662 up by hand, either by pushing onto the stack or copying into a
663 return-address register as appropriate. Formerly this has been
664 done in PUSH_ARGUMENTS, but that's overloading its
665 functionality a bit, so I'm making it explicit to do it here. */
666 /* NOTE: cagney/2003-04-22: The first parameter ("real_pc") has
667 been replaced with zero, it turns out that no implementation
668 used that parameter. This occured because the value being
669 supplied - the address of the called function's entry point
670 instead of the address of the breakpoint that the called
671 function should return to - wasn't useful. */
672 sp
= DEPRECATED_PUSH_RETURN_ADDRESS (0, sp
);
674 /* NOTE: cagney/2003-03-23: Diable this code when there is a
675 push_dummy_call() method. Since that method will have already
676 handled any alignment issues, the code below is entirely
678 if (!gdbarch_push_dummy_call_p (current_gdbarch
)
679 && STACK_ALIGN_P () && !INNER_THAN (1, 2))
681 /* If stack grows up, we must leave a hole at the bottom, note
682 that sp already has been advanced for the arguments! */
683 if (DEPRECATED_CALL_DUMMY_STACK_ADJUST_P ())
684 sp
+= DEPRECATED_CALL_DUMMY_STACK_ADJUST
;
685 sp
= STACK_ALIGN (sp
);
688 /* XXX This seems wrong. For stacks that grow down we shouldn't do
690 /* MVS 11/22/96: I think at least some of this stack_align code is
691 really broken. Better to let PUSH_ARGUMENTS adjust the stack in
692 a target-defined manner. */
693 if (DEPRECATED_CALL_DUMMY_STACK_ADJUST_P ())
694 if (INNER_THAN (1, 2))
696 /* stack grows downward */
697 sp
-= DEPRECATED_CALL_DUMMY_STACK_ADJUST
;
700 /* Store the address at which the structure is supposed to be
702 /* NOTE: 2003-03-24: Since PUSH_ARGUMENTS can (and typically does)
703 store the struct return address, this call is entirely redundant. */
704 if (struct_return
&& DEPRECATED_STORE_STRUCT_RETURN_P ())
705 DEPRECATED_STORE_STRUCT_RETURN (struct_addr
, sp
);
707 /* Write the stack pointer. This is here because the statements above
708 might fool with it. On SPARC, this write also stores the register
709 window into the right place in the new stack frame, which otherwise
710 wouldn't happen. (See store_inferior_registers in sparc-nat.c.) */
711 /* NOTE: cagney/2003-03-23: Disable this code when there is a
712 push_dummy_call() method. Since that method will have already
713 stored the stack pointer (as part of creating the fake call
714 frame), and none of the code following that code adjusts the
715 stack-pointer value, the below call is entirely redundant. */
716 if (DEPRECATED_DUMMY_WRITE_SP_P ())
717 DEPRECATED_DUMMY_WRITE_SP (sp
);
719 if (SAVE_DUMMY_FRAME_TOS_P ())
720 SAVE_DUMMY_FRAME_TOS (sp
);
724 struct symbol
*symbol
;
727 symbol
= find_pc_function (funaddr
);
730 name
= SYMBOL_PRINT_NAME (symbol
);
734 /* Try the minimal symbols. */
735 struct minimal_symbol
*msymbol
= lookup_minimal_symbol_by_pc (funaddr
);
739 name
= SYMBOL_PRINT_NAME (msymbol
);
745 sprintf (format
, "at %s", local_hex_format ());
747 /* FIXME-32x64: assumes funaddr fits in a long. */
748 sprintf (name
, format
, (unsigned long) funaddr
);
752 /* Execute a "stack dummy", a piece of code stored in the stack
753 by the debugger to be executed in the inferior.
755 The dummy's frame is automatically popped whenever that break
756 is hit. If that is the first time the program stops,
757 call_function_by_hand returns to its caller with that frame
758 already gone and sets RC to 0.
760 Otherwise, set RC to a non-zero value. If the called
761 function receives a random signal, we do not allow the user
762 to continue executing it as this may not work. The dummy
763 frame is poped and we return 1. If we hit a breakpoint, we
764 leave the frame in place and return 2 (the frame will
765 eventually be popped when we do hit the dummy end
768 struct regcache
*buffer
= retbuf
;
769 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, 0);
771 struct breakpoint
*bpt
;
772 struct symtab_and_line sal
;
774 /* Now proceed, having reached the desired place. */
775 clear_proceed_status ();
777 init_sal (&sal
); /* initialize to zeroes */
779 sal
.section
= find_pc_overlay (sal
.pc
);
782 /* Set up a frame ID for the dummy frame so we can pass it to
783 set_momentary_breakpoint. We need to give the breakpoint a
784 frame ID so that the breakpoint code can correctly
785 re-identify the dummy breakpoint. */
786 struct frame_id frame
= frame_id_build (read_fp (), sal
.pc
);
787 /* Create a momentary breakpoint at the return address of the
788 inferior. That way it breaks when it returns. */
789 bpt
= set_momentary_breakpoint (sal
, frame
, bp_call_dummy
);
790 bpt
->disposition
= disp_del
;
793 /* If all error()s out of proceed ended up calling normal_stop
794 (and perhaps they should; it already does in the special case
795 of error out of resume()), then we wouldn't need this. */
796 make_cleanup (breakpoint_auto_delete_contents
, &stop_bpstat
);
798 disable_watchpoints_before_interactive_call_start ();
799 proceed_to_finish
= 1; /* We want stop_registers, please... */
801 if (target_can_async_p ())
802 saved_async
= target_async_mask (0);
804 proceed (real_pc
, TARGET_SIGNAL_0
, 0);
807 target_async_mask (saved_async
);
809 enable_watchpoints_after_interactive_call_stop ();
811 discard_cleanups (old_cleanups
);
813 if (stopped_by_random_signal
)
814 /* We can stop during an inferior call because a signal is
817 else if (!stop_stack_dummy
)
818 /* We may also stop prematurely because we hit a breakpoint in
819 the called routine. */
823 /* On normal return, the stack dummy has been popped
825 regcache_cpy_no_passthrough (buffer
, stop_registers
);
832 /* We stopped inside the FUNCTION because of a random signal.
833 Further execution of the FUNCTION is not allowed. */
835 if (unwind_on_signal_p
)
837 /* The user wants the context restored. */
839 /* We must get back to the frame we were before the dummy
841 frame_pop (get_current_frame ());
843 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
844 a C++ name with arguments and stuff. */
846 The program being debugged was signaled while in a function called from GDB.\n\
847 GDB has restored the context to what it was before the call.\n\
848 To change this behavior use \"set unwindonsignal off\"\n\
849 Evaluation of the expression containing the function (%s) will be abandoned.",
854 /* The user wants to stay in the frame where we stopped (default).*/
856 /* If we restored the inferior status (via the cleanup),
857 we would print a spurious error message (Unable to
858 restore previously selected frame), would write the
859 registers from the inf_status (which is wrong), and
860 would do other wrong things. */
861 discard_cleanups (inf_status_cleanup
);
862 discard_inferior_status (inf_status
);
864 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
865 a C++ name with arguments and stuff. */
867 The program being debugged was signaled while in a function called from GDB.\n\
868 GDB remains in the frame where the signal was received.\n\
869 To change this behavior use \"set unwindonsignal on\"\n\
870 Evaluation of the expression containing the function (%s) will be abandoned.",
877 /* We hit a breakpoint inside the FUNCTION. */
879 /* If we restored the inferior status (via the cleanup), we
880 would print a spurious error message (Unable to restore
881 previously selected frame), would write the registers from
882 the inf_status (which is wrong), and would do other wrong
884 discard_cleanups (inf_status_cleanup
);
885 discard_inferior_status (inf_status
);
887 /* The following error message used to say "The expression
888 which contained the function call has been discarded." It
889 is a hard concept to explain in a few words. Ideally, GDB
890 would be able to resume evaluation of the expression when
891 the function finally is done executing. Perhaps someday
892 this will be implemented (it would not be easy). */
894 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
895 a C++ name with arguments and stuff. */
897 The program being debugged stopped while in a function called from GDB.\n\
898 When the function (%s) is done executing, GDB will silently\n\
899 stop (instead of continuing to evaluate the expression containing\n\
900 the function call).", name
);
903 /* If we get here the called FUNCTION run to completion. */
905 /* Restore the inferior status, via its cleanup. At this stage,
906 leave the RETBUF alone. */
907 do_cleanups (inf_status_cleanup
);
909 /* Figure out the value returned by the function. */
910 /* elz: I defined this new macro for the hppa architecture only.
911 this gives us a way to get the value returned by the function
912 from the stack, at the same address we told the function to put
913 it. We cannot assume on the pa that r28 still contains the
914 address of the returned structure. Usually this will be
915 overwritten by the callee. I don't know about other
916 architectures, so I defined this macro */
917 #ifdef VALUE_RETURNED_FROM_STACK
920 do_cleanups (retbuf_cleanup
);
921 return VALUE_RETURNED_FROM_STACK (value_type
, struct_addr
);
924 /* NOTE: cagney/2002-09-10: Only when the stack has been correctly
925 aligned (using frame_align()) do we can trust STRUCT_ADDR and
926 fetch the return value direct from the stack. This lack of
927 trust comes about because legacy targets have a nasty habit of
928 silently, and local to PUSH_ARGUMENTS(), moving STRUCT_ADDR.
929 For such targets, just hope that value_being_returned() can
930 find the adjusted value. */
931 if (struct_return
&& gdbarch_frame_align_p (current_gdbarch
))
933 struct value
*retval
= value_at (value_type
, struct_addr
, NULL
);
934 do_cleanups (retbuf_cleanup
);
939 struct value
*retval
= value_being_returned (value_type
, retbuf
,
941 do_cleanups (retbuf_cleanup
);
947 void _initialize_infcall (void);
950 _initialize_infcall (void)
952 add_setshow_boolean_cmd ("coerce-float-to-double", class_obscure
,
953 &coerce_float_to_double_p
, "\
954 Set coercion of floats to doubles when calling functions\n\
955 Variables of type float should generally be converted to doubles before\n\
956 calling an unprototyped function, and left alone when calling a prototyped\n\
957 function. However, some older debug info formats do not provide enough\n\
958 information to determine that a function is prototyped. If this flag is\n\
959 set, GDB will perform the conversion for a function it considers\n\
961 The default is to perform the conversion.\n", "\
962 Show coercion of floats to doubles when calling functions\n\
963 Variables of type float should generally be converted to doubles before\n\
964 calling an unprototyped function, and left alone when calling a prototyped\n\
965 function. However, some older debug info formats do not provide enough\n\
966 information to determine that a function is prototyped. If this flag is\n\
967 set, GDB will perform the conversion for a function it considers\n\
969 The default is to perform the conversion.\n",
970 NULL
, NULL
, &setlist
, &showlist
);
972 add_setshow_boolean_cmd ("unwindonsignal", no_class
,
973 &unwind_on_signal_p
, "\
974 Set unwinding of stack if a signal is received while in a call dummy.\n\
975 The unwindonsignal lets the user determine what gdb should do if a signal\n\
976 is received while in a function called from gdb (call dummy). If set, gdb\n\
977 unwinds the stack and restore the context to what as it was before the call.\n\
978 The default is to stop in the frame where the signal was received.", "\
979 Set unwinding of stack if a signal is received while in a call dummy.\n\
980 The unwindonsignal lets the user determine what gdb should do if a signal\n\
981 is received while in a function called from gdb (call dummy). If set, gdb\n\
982 unwinds the stack and restore the context to what as it was before the call.\n\
983 The default is to stop in the frame where the signal was received.",
984 NULL
, NULL
, &setlist
, &showlist
);