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;
276 dummy
= alloca (SIZEOF_CALL_DUMMY_WORDS
);
277 sizeof_dummy1
= REGISTER_SIZE
* SIZEOF_CALL_DUMMY_WORDS
/ sizeof (ULONGEST
);
278 dummy1
= alloca (sizeof_dummy1
);
279 memcpy (dummy
, CALL_DUMMY_WORDS
, SIZEOF_CALL_DUMMY_WORDS
);
281 if (!target_has_execution
)
284 /* Create a cleanup chain that contains the retbuf (buffer
285 containing the register values). This chain is create BEFORE the
286 inf_status chain so that the inferior status can cleaned up
287 (restored or discarded) without having the retbuf freed. */
288 retbuf
= regcache_xmalloc (current_gdbarch
);
289 retbuf_cleanup
= make_cleanup_regcache_xfree (retbuf
);
291 /* A cleanup for the inferior status. Create this AFTER the retbuf
292 so that this can be discarded or applied without interfering with
294 inf_status
= save_inferior_status (1);
295 inf_status_cleanup
= make_cleanup_restore_inferior_status (inf_status
);
297 if (DEPRECATED_PUSH_DUMMY_FRAME_P ())
299 /* DEPRECATED_PUSH_DUMMY_FRAME is responsible for saving the
300 inferior registers (and frame_pop() for restoring them). (At
301 least on most machines) they are saved on the stack in the
303 DEPRECATED_PUSH_DUMMY_FRAME
;
307 /* FIXME: cagney/2003-02-26: Step zero of this little tinker is
308 to extract the generic dummy frame code from the architecture
309 vector. Hence this direct call.
311 A follow-on change is to modify this interface so that it takes
312 thread OR frame OR tpid as a parameter, and returns a dummy
313 frame handle. The handle can then be used further down as a
314 parameter SAVE_DUMMY_FRAME_TOS. Hmm, thinking about it, since
315 everything is ment to be using generic dummy frames, why not
316 even use some of the dummy frame code to here - do a regcache
317 dup and then pass the duped regcache, along with all the other
318 stuff, at one single point.
320 In fact, you can even save the structure's return address in the
321 dummy frame and fix one of those nasty lost struct return edge
323 generic_push_dummy_frame ();
328 /* Ensure that the initial SP is correctly aligned. */
329 if (gdbarch_frame_align_p (current_gdbarch
))
331 /* NOTE: cagney/2002-09-18:
333 On a RISC architecture, a void parameterless generic dummy
334 frame (i.e., no parameters, no result) typically does not
335 need to push anything the stack and hence can leave SP and
336 FP. Similarly, a framelss (possibly leaf) function does not
337 push anything on the stack and, hence, that too can leave FP
338 and SP unchanged. As a consequence, a sequence of void
339 parameterless generic dummy frame calls to frameless
340 functions will create a sequence of effectively identical
341 frames (SP, FP and TOS and PC the same). This, not
342 suprisingly, results in what appears to be a stack in an
343 infinite loop --- when GDB tries to find a generic dummy
344 frame on the internal dummy frame stack, it will always find
347 To avoid this problem, the code below always grows the stack.
348 That way, two dummy frames can never be identical. It does
349 burn a few bytes of stack but that is a small price to pay
351 sp
= gdbarch_frame_align (current_gdbarch
, old_sp
);
354 if (INNER_THAN (1, 2))
355 /* Stack grows down. */
356 sp
= gdbarch_frame_align (current_gdbarch
, old_sp
- 1);
358 /* Stack grows up. */
359 sp
= gdbarch_frame_align (current_gdbarch
, old_sp
+ 1);
361 gdb_assert ((INNER_THAN (1, 2) && sp
<= old_sp
)
362 || (INNER_THAN (2, 1) && sp
>= old_sp
));
365 /* FIXME: cagney/2002-09-18: Hey, you loose! Who knows how badly
366 aligned the SP is! Further, per comment above, if the generic
367 dummy frame ends up empty (because nothing is pushed) GDB won't
368 be able to correctly perform back traces. If a target is
369 having trouble with backtraces, first thing to do is add
370 FRAME_ALIGN() to its architecture vector. After that, try
371 adding SAVE_DUMMY_FRAME_TOS() and modifying
372 DEPRECATED_FRAME_CHAIN so that when the next outer frame is a
373 generic dummy, it returns the current frame's base. */
376 if (INNER_THAN (1, 2))
378 /* Stack grows down */
389 /* NOTE: cagney/2002-09-10: Don't bother re-adjusting the stack
390 after allocating space for the call dummy. A target can specify
391 a SIZEOF_DUMMY1 (via SIZEOF_CALL_DUMMY_WORDS) such that all local
392 alignment requirements are met. */
394 funaddr
= find_function_addr (function
, &value_type
);
395 CHECK_TYPEDEF (value_type
);
398 struct block
*b
= block_for_pc (funaddr
);
399 /* If compiled without -g, assume GCC 2. */
400 using_gcc
= (b
== NULL
? 2 : BLOCK_GCC_COMPILED (b
));
403 /* Are we returning a value using a structure return or a normal
406 struct_return
= using_struct_return (function
, funaddr
, value_type
,
409 /* Create a call sequence customized for this function
410 and the number of arguments for it. */
411 for (i
= 0; i
< (int) (SIZEOF_CALL_DUMMY_WORDS
/ sizeof (dummy
[0])); i
++)
412 store_unsigned_integer (&dummy1
[i
* REGISTER_SIZE
],
414 (ULONGEST
) dummy
[i
]);
416 #ifdef GDB_TARGET_IS_HPPA
417 real_pc
= FIX_CALL_DUMMY (dummy1
, start_sp
, funaddr
, nargs
, args
,
418 value_type
, using_gcc
);
420 if (FIX_CALL_DUMMY_P ())
422 /* gdb_assert (CALL_DUMMY_LOCATION == ON_STACK) true? */
423 FIX_CALL_DUMMY (dummy1
, start_sp
, funaddr
, nargs
, args
, value_type
,
429 switch (CALL_DUMMY_LOCATION
)
432 dummy_addr
= start_sp
;
433 write_memory (start_sp
, (char *) dummy1
, sizeof_dummy1
);
434 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
)
435 generic_save_call_dummy_addr (start_sp
, start_sp
+ sizeof_dummy1
);
439 dummy_addr
= CALL_DUMMY_ADDRESS ();
440 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
)
441 /* NOTE: cagney/2002-04-13: The entry point is going to be
442 modified with a single breakpoint. */
443 generic_save_call_dummy_addr (CALL_DUMMY_ADDRESS (),
444 CALL_DUMMY_ADDRESS () + 1);
447 internal_error (__FILE__
, __LINE__
, "bad switch");
451 sp
= old_sp
; /* It really is used, for some ifdef's... */
454 if (nargs
< TYPE_NFIELDS (ftype
))
455 error ("too few arguments in function call");
457 for (i
= nargs
- 1; i
>= 0; i
--)
461 /* FIXME drow/2002-05-31: Should just always mark methods as
462 prototyped. Can we respect TYPE_VARARGS? Probably not. */
463 if (TYPE_CODE (ftype
) == TYPE_CODE_METHOD
)
466 prototyped
= TYPE_PROTOTYPED (ftype
);
468 if (i
< TYPE_NFIELDS (ftype
))
469 args
[i
] = value_arg_coerce (args
[i
], TYPE_FIELD_TYPE (ftype
, i
),
472 args
[i
] = value_arg_coerce (args
[i
], NULL
, 0);
474 /*elz: this code is to handle the case in which the function to be called
475 has a pointer to function as parameter and the corresponding actual argument
476 is the address of a function and not a pointer to function variable.
477 In aCC compiled code, the calls through pointers to functions (in the body
478 of the function called by hand) are made via $$dyncall_external which
479 requires some registers setting, this is taken care of if we call
480 via a function pointer variable, but not via a function address.
481 In cc this is not a problem. */
484 if (param_type
&& TYPE_CODE (ftype
) != TYPE_CODE_METHOD
)
485 /* if this parameter is a pointer to function */
486 if (TYPE_CODE (param_type
) == TYPE_CODE_PTR
)
487 if (TYPE_CODE (TYPE_TARGET_TYPE (param_type
)) == TYPE_CODE_FUNC
)
488 /* elz: FIXME here should go the test about the compiler used
489 to compile the target. We want to issue the error
490 message only if the compiler used was HP's aCC.
491 If we used HP's cc, then there is no problem and no need
492 to return at this point */
493 if (using_gcc
== 0) /* && compiler == aCC */
494 /* go see if the actual parameter is a variable of type
495 pointer to function or just a function */
496 if (args
[i
]->lval
== not_lval
)
499 if (find_pc_partial_function ((CORE_ADDR
) args
[i
]->aligner
.contents
[0], &arg_name
, NULL
, NULL
))
501 You cannot use function <%s> as argument. \n\
502 You must use a pointer to function type variable. Command ignored.", arg_name
);
506 if (REG_STRUCT_HAS_ADDR_P ())
508 /* This is a machine like the sparc, where we may need to pass a
509 pointer to the structure, not the structure itself. */
510 for (i
= nargs
- 1; i
>= 0; i
--)
512 struct type
*arg_type
= check_typedef (VALUE_TYPE (args
[i
]));
513 if ((TYPE_CODE (arg_type
) == TYPE_CODE_STRUCT
514 || TYPE_CODE (arg_type
) == TYPE_CODE_UNION
515 || TYPE_CODE (arg_type
) == TYPE_CODE_ARRAY
516 || TYPE_CODE (arg_type
) == TYPE_CODE_STRING
517 || TYPE_CODE (arg_type
) == TYPE_CODE_BITSTRING
518 || TYPE_CODE (arg_type
) == TYPE_CODE_SET
519 || (TYPE_CODE (arg_type
) == TYPE_CODE_FLT
520 && TYPE_LENGTH (arg_type
) > 8)
522 && REG_STRUCT_HAS_ADDR (using_gcc
, arg_type
))
525 int len
; /* = TYPE_LENGTH (arg_type); */
527 arg_type
= check_typedef (VALUE_ENCLOSING_TYPE (args
[i
]));
528 len
= TYPE_LENGTH (arg_type
);
530 if (STACK_ALIGN_P ())
531 /* MVS 11/22/96: I think at least some of this
532 stack_align code is really broken. Better to let
533 PUSH_ARGUMENTS adjust the stack in a target-defined
535 aligned_len
= STACK_ALIGN (len
);
538 if (INNER_THAN (1, 2))
540 /* stack grows downward */
542 /* ... so the address of the thing we push is the
543 stack pointer after we push it. */
548 /* The stack grows up, so the address of the thing
549 we push is the stack pointer before we push it. */
553 /* Push the structure. */
554 write_memory (addr
, VALUE_CONTENTS_ALL (args
[i
]), len
);
555 /* The value we're going to pass is the address of the
556 thing we just pushed. */
557 /*args[i] = value_from_longest (lookup_pointer_type (value_type),
559 args
[i
] = value_from_pointer (lookup_pointer_type (arg_type
),
566 /* Reserve space for the return structure to be written on the
567 stack, if necessary. Make certain that the value is correctly
572 int len
= TYPE_LENGTH (value_type
);
573 if (STACK_ALIGN_P ())
574 /* NOTE: cagney/2003-03-22: Should rely on frame align, rather
575 than stack align to force the alignment of the stack. */
576 len
= STACK_ALIGN (len
);
577 if (INNER_THAN (1, 2))
579 /* Stack grows downward. Align STRUCT_ADDR and SP after
580 making space for the return value. */
582 if (gdbarch_frame_align_p (current_gdbarch
))
583 sp
= gdbarch_frame_align (current_gdbarch
, sp
);
588 /* Stack grows upward. Align the frame, allocate space, and
589 then again, re-align the frame??? */
590 if (gdbarch_frame_align_p (current_gdbarch
))
591 sp
= gdbarch_frame_align (current_gdbarch
, sp
);
594 if (gdbarch_frame_align_p (current_gdbarch
))
595 sp
= gdbarch_frame_align (current_gdbarch
, sp
);
599 /* elz: on HPPA no need for this extra alignment, maybe it is needed
600 on other architectures. This is because all the alignment is
601 taken care of in the above code (ifdef REG_STRUCT_HAS_ADDR) and
602 in hppa_push_arguments */
603 /* NOTE: cagney/2003-03-24: The below code is very broken. Given an
604 odd sized parameter the below will mis-align the stack. As was
605 suggested back in '96, better to let PUSH_ARGUMENTS handle it. */
606 if (DEPRECATED_EXTRA_STACK_ALIGNMENT_NEEDED
)
608 /* MVS 11/22/96: I think at least some of this stack_align code
609 is really broken. Better to let push_dummy_call() adjust the
610 stack in a target-defined manner. */
611 if (STACK_ALIGN_P () && INNER_THAN (1, 2))
613 /* If stack grows down, we must leave a hole at the top. */
616 for (i
= nargs
- 1; i
>= 0; i
--)
617 len
+= TYPE_LENGTH (VALUE_ENCLOSING_TYPE (args
[i
]));
618 if (DEPRECATED_CALL_DUMMY_STACK_ADJUST_P ())
619 len
+= DEPRECATED_CALL_DUMMY_STACK_ADJUST
;
620 sp
-= STACK_ALIGN (len
) - len
;
624 /* Create the dummy stack frame. Pass in the call dummy address as,
625 presumably, the ABI code knows where, in the call dummy, the
626 return address should be pointed. */
627 if (gdbarch_push_dummy_call_p (current_gdbarch
))
628 /* When there is no push_dummy_call method, should this code
629 simply error out. That would the implementation of this method
630 for all ABIs (which is probably a good thing). */
631 sp
= gdbarch_push_dummy_call (current_gdbarch
, current_regcache
,
632 dummy_addr
, nargs
, args
, sp
, struct_return
,
634 else if (DEPRECATED_PUSH_ARGUMENTS_P ())
635 /* Keep old targets working. */
636 sp
= DEPRECATED_PUSH_ARGUMENTS (nargs
, args
, sp
, struct_return
,
639 sp
= legacy_push_arguments (nargs
, args
, sp
, struct_return
, struct_addr
);
641 if (DEPRECATED_PUSH_RETURN_ADDRESS_P ())
642 /* for targets that use no CALL_DUMMY */
643 /* There are a number of targets now which actually don't write
644 any CALL_DUMMY instructions into the target, but instead just
645 save the machine state, push the arguments, and jump directly
646 to the callee function. Since this doesn't actually involve
647 executing a JSR/BSR instruction, the return address must be set
648 up by hand, either by pushing onto the stack or copying into a
649 return-address register as appropriate. Formerly this has been
650 done in PUSH_ARGUMENTS, but that's overloading its
651 functionality a bit, so I'm making it explicit to do it here. */
652 sp
= DEPRECATED_PUSH_RETURN_ADDRESS (real_pc
, sp
);
654 /* NOTE: cagney/2003-03-23: Diable this code when there is a
655 push_dummy_call() method. Since that method will have already
656 handled any alignment issues, the code below is entirely
658 if (!gdbarch_push_dummy_call_p (current_gdbarch
)
659 && STACK_ALIGN_P () && !INNER_THAN (1, 2))
661 /* If stack grows up, we must leave a hole at the bottom, note
662 that sp already has been advanced for the arguments! */
663 if (DEPRECATED_CALL_DUMMY_STACK_ADJUST_P ())
664 sp
+= DEPRECATED_CALL_DUMMY_STACK_ADJUST
;
665 sp
= STACK_ALIGN (sp
);
668 /* XXX This seems wrong. For stacks that grow down we shouldn't do
670 /* MVS 11/22/96: I think at least some of this stack_align code is
671 really broken. Better to let PUSH_ARGUMENTS adjust the stack in
672 a target-defined manner. */
673 if (DEPRECATED_CALL_DUMMY_STACK_ADJUST_P ())
674 if (INNER_THAN (1, 2))
676 /* stack grows downward */
677 sp
-= DEPRECATED_CALL_DUMMY_STACK_ADJUST
;
680 /* Store the address at which the structure is supposed to be
682 /* NOTE: 2003-03-24: Since PUSH_ARGUMENTS can (and typically does)
683 store the struct return address, this call is entirely redundant. */
684 if (struct_return
&& DEPRECATED_STORE_STRUCT_RETURN_P ())
685 DEPRECATED_STORE_STRUCT_RETURN (struct_addr
, sp
);
687 /* Write the stack pointer. This is here because the statements above
688 might fool with it. On SPARC, this write also stores the register
689 window into the right place in the new stack frame, which otherwise
690 wouldn't happen. (See store_inferior_registers in sparc-nat.c.) */
691 /* NOTE: cagney/2003-03-23: Disable this code when there is a
692 push_dummy_call() method. Since that method will have already
693 stored the stack pointer (as part of creating the fake call
694 frame), and none of the code following that code adjusts the
695 stack-pointer value, the below call is entirely redundant. */
696 if (DEPRECATED_DUMMY_WRITE_SP_P ())
697 DEPRECATED_DUMMY_WRITE_SP (sp
);
699 if (SAVE_DUMMY_FRAME_TOS_P ())
700 SAVE_DUMMY_FRAME_TOS (sp
);
704 struct symbol
*symbol
;
707 symbol
= find_pc_function (funaddr
);
710 name
= SYMBOL_PRINT_NAME (symbol
);
714 /* Try the minimal symbols. */
715 struct minimal_symbol
*msymbol
= lookup_minimal_symbol_by_pc (funaddr
);
719 name
= SYMBOL_PRINT_NAME (msymbol
);
725 sprintf (format
, "at %s", local_hex_format ());
727 /* FIXME-32x64: assumes funaddr fits in a long. */
728 sprintf (name
, format
, (unsigned long) funaddr
);
732 /* Execute a "stack dummy", a piece of code stored in the stack
733 by the debugger to be executed in the inferior.
735 The dummy's frame is automatically popped whenever that break
736 is hit. If that is the first time the program stops,
737 call_function_by_hand returns to its caller with that frame
738 already gone and sets RC to 0.
740 Otherwise, set RC to a non-zero value. If the called
741 function receives a random signal, we do not allow the user
742 to continue executing it as this may not work. The dummy
743 frame is poped and we return 1. If we hit a breakpoint, we
744 leave the frame in place and return 2 (the frame will
745 eventually be popped when we do hit the dummy end
748 CORE_ADDR addr
= real_pc
+ CALL_DUMMY_START_OFFSET
;
749 struct regcache
*buffer
= retbuf
;
750 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, 0);
752 struct breakpoint
*bpt
;
753 struct symtab_and_line sal
;
755 /* Now proceed, having reached the desired place. */
756 clear_proceed_status ();
758 init_sal (&sal
); /* initialize to zeroes */
759 if (CALL_DUMMY_LOCATION
== AT_ENTRY_POINT
)
761 sal
.pc
= CALL_DUMMY_ADDRESS ();
765 /* If defined, CALL_DUMMY_BREAKPOINT_OFFSET is where we need
766 to put a breakpoint instruction. If not, the call dummy
767 already has the breakpoint instruction in it.
769 ADDR IS THE ADDRESS of the call dummy plus the
770 CALL_DUMMY_START_OFFSET, so we need to subtract the
771 CALL_DUMMY_START_OFFSET. */
772 sal
.pc
= (addr
- (CALL_DUMMY_START_OFFSET
773 + CALL_DUMMY_BREAKPOINT_OFFSET
));
775 sal
.section
= find_pc_overlay (sal
.pc
);
778 /* Set up a frame ID for the dummy frame so we can pass it to
779 set_momentary_breakpoint. We need to give the breakpoint a
780 frame ID so that the breakpoint code can correctly
781 re-identify the dummy breakpoint. */
782 struct frame_id frame
= frame_id_build (read_fp (), sal
.pc
);
783 /* Create a momentary breakpoint at the return address of the
784 inferior. That way it breaks when it returns. */
785 bpt
= set_momentary_breakpoint (sal
, frame
, bp_call_dummy
);
786 bpt
->disposition
= disp_del
;
789 /* If all error()s out of proceed ended up calling normal_stop
790 (and perhaps they should; it already does in the special case
791 of error out of resume()), then we wouldn't need this. */
792 make_cleanup (breakpoint_auto_delete_contents
, &stop_bpstat
);
794 disable_watchpoints_before_interactive_call_start ();
795 proceed_to_finish
= 1; /* We want stop_registers, please... */
797 if (target_can_async_p ())
798 saved_async
= target_async_mask (0);
800 proceed (addr
, TARGET_SIGNAL_0
, 0);
803 target_async_mask (saved_async
);
805 enable_watchpoints_after_interactive_call_stop ();
807 discard_cleanups (old_cleanups
);
809 if (stopped_by_random_signal
)
810 /* We can stop during an inferior call because a signal is
813 else if (!stop_stack_dummy
)
814 /* We may also stop prematurely because we hit a breakpoint in
815 the called routine. */
819 /* On normal return, the stack dummy has been popped
821 regcache_cpy_no_passthrough (buffer
, stop_registers
);
828 /* We stopped inside the FUNCTION because of a random signal.
829 Further execution of the FUNCTION is not allowed. */
831 if (unwind_on_signal_p
)
833 /* The user wants the context restored. */
835 /* We must get back to the frame we were before the dummy
837 frame_pop (get_current_frame ());
839 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
840 a C++ name with arguments and stuff. */
842 The program being debugged was signaled while in a function called from GDB.\n\
843 GDB has restored the context to what it was before the call.\n\
844 To change this behavior use \"set unwindonsignal off\"\n\
845 Evaluation of the expression containing the function (%s) will be abandoned.",
850 /* The user wants to stay in the frame where we stopped (default).*/
852 /* If we restored the inferior status (via the cleanup),
853 we would print a spurious error message (Unable to
854 restore previously selected frame), would write the
855 registers from the inf_status (which is wrong), and
856 would do other wrong things. */
857 discard_cleanups (inf_status_cleanup
);
858 discard_inferior_status (inf_status
);
860 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
861 a C++ name with arguments and stuff. */
863 The program being debugged was signaled while in a function called from GDB.\n\
864 GDB remains in the frame where the signal was received.\n\
865 To change this behavior use \"set unwindonsignal on\"\n\
866 Evaluation of the expression containing the function (%s) will be abandoned.",
873 /* We hit a breakpoint inside the FUNCTION. */
875 /* If we restored the inferior status (via the cleanup), we
876 would print a spurious error message (Unable to restore
877 previously selected frame), would write the registers from
878 the inf_status (which is wrong), and would do other wrong
880 discard_cleanups (inf_status_cleanup
);
881 discard_inferior_status (inf_status
);
883 /* The following error message used to say "The expression
884 which contained the function call has been discarded." It
885 is a hard concept to explain in a few words. Ideally, GDB
886 would be able to resume evaluation of the expression when
887 the function finally is done executing. Perhaps someday
888 this will be implemented (it would not be easy). */
890 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
891 a C++ name with arguments and stuff. */
893 The program being debugged stopped while in a function called from GDB.\n\
894 When the function (%s) is done executing, GDB will silently\n\
895 stop (instead of continuing to evaluate the expression containing\n\
896 the function call).", name
);
899 /* If we get here the called FUNCTION run to completion. */
901 /* Restore the inferior status, via its cleanup. At this stage,
902 leave the RETBUF alone. */
903 do_cleanups (inf_status_cleanup
);
905 /* Figure out the value returned by the function. */
906 /* elz: I defined this new macro for the hppa architecture only.
907 this gives us a way to get the value returned by the function
908 from the stack, at the same address we told the function to put
909 it. We cannot assume on the pa that r28 still contains the
910 address of the returned structure. Usually this will be
911 overwritten by the callee. I don't know about other
912 architectures, so I defined this macro */
913 #ifdef VALUE_RETURNED_FROM_STACK
916 do_cleanups (retbuf_cleanup
);
917 return VALUE_RETURNED_FROM_STACK (value_type
, struct_addr
);
920 /* NOTE: cagney/2002-09-10: Only when the stack has been correctly
921 aligned (using frame_align()) do we can trust STRUCT_ADDR and
922 fetch the return value direct from the stack. This lack of
923 trust comes about because legacy targets have a nasty habit of
924 silently, and local to PUSH_ARGUMENTS(), moving STRUCT_ADDR.
925 For such targets, just hope that value_being_returned() can
926 find the adjusted value. */
927 if (struct_return
&& gdbarch_frame_align_p (current_gdbarch
))
929 struct value
*retval
= value_at (value_type
, struct_addr
, NULL
);
930 do_cleanups (retbuf_cleanup
);
935 struct value
*retval
= value_being_returned (value_type
, retbuf
,
937 do_cleanups (retbuf_cleanup
);
943 void _initialize_infcall (void);
946 _initialize_infcall (void)
948 add_setshow_boolean_cmd ("coerce-float-to-double", class_obscure
,
949 &coerce_float_to_double_p
, "\
950 Set coercion of floats to doubles when calling functions\n\
951 Variables of type float should generally be converted to doubles before\n\
952 calling an unprototyped function, and left alone when calling a prototyped\n\
953 function. However, some older debug info formats do not provide enough\n\
954 information to determine that a function is prototyped. If this flag is\n\
955 set, GDB will perform the conversion for a function it considers\n\
957 The default is to perform the conversion.\n", "\
958 Show coercion of floats to doubles when calling functions\n\
959 Variables of type float should generally be converted to doubles before\n\
960 calling an unprototyped function, and left alone when calling a prototyped\n\
961 function. However, some older debug info formats do not provide enough\n\
962 information to determine that a function is prototyped. If this flag is\n\
963 set, GDB will perform the conversion for a function it considers\n\
965 The default is to perform the conversion.\n",
966 NULL
, NULL
, &setlist
, &showlist
);
968 add_setshow_boolean_cmd ("unwindonsignal", no_class
,
969 &unwind_on_signal_p
, "\
970 Set unwinding of stack if a signal is received while in a call dummy.\n\
971 The unwindonsignal lets the user determine what gdb should do if a signal\n\
972 is received while in a function called from gdb (call dummy). If set, gdb\n\
973 unwinds the stack and restore the context to what as it was before the call.\n\
974 The default is to stop in the frame where the signal was received.", "\
975 Set unwinding of stack if a signal is received while in a call dummy.\n\
976 The unwindonsignal lets the user determine what gdb should do if a signal\n\
977 is received while in a function called from gdb (call dummy). If set, gdb\n\
978 unwinds the stack and restore the context to what as it was before the call.\n\
979 The default is to stop in the frame where the signal was received.",
980 NULL
, NULL
, &setlist
, &showlist
);