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"
39 /* NOTE: cagney/2003-04-16: What's the future of this code?
41 GDB needs an asynchronous expression evaluator, that means an
42 asynchronous inferior function call implementation, and that in
43 turn means restructuring the code so that it is event driven. */
45 /* How you should pass arguments to a function depends on whether it
46 was defined in K&R style or prototype style. If you define a
47 function using the K&R syntax that takes a `float' argument, then
48 callers must pass that argument as a `double'. If you define the
49 function using the prototype syntax, then you must pass the
50 argument as a `float', with no promotion.
52 Unfortunately, on certain older platforms, the debug info doesn't
53 indicate reliably how each function was defined. A function type's
54 TYPE_FLAG_PROTOTYPED flag may be clear, even if the function was
55 defined in prototype style. When calling a function whose
56 TYPE_FLAG_PROTOTYPED flag is clear, GDB consults this flag to
59 For modern targets, it is proper to assume that, if the prototype
60 flag is clear, that can be trusted: `float' arguments should be
61 promoted to `double'. For some older targets, if the prototype
62 flag is clear, that doesn't tell us anything. The default is to
63 trust the debug information; the user can override this behavior
64 with "set coerce-float-to-double 0". */
66 static int coerce_float_to_double_p
= 1;
68 /* This boolean tells what gdb should do if a signal is received while
69 in a function called from gdb (call dummy). If set, gdb unwinds
70 the stack and restore the context to what as it was before the
73 The default is to stop in the frame where the signal was received. */
75 int unwind_on_signal_p
= 0;
77 /* Perform the standard coercions that are specified
78 for arguments to be passed to C functions.
80 If PARAM_TYPE is non-NULL, it is the expected parameter type.
81 IS_PROTOTYPED is non-zero if the function declaration is prototyped. */
84 value_arg_coerce (struct value
*arg
, struct type
*param_type
,
87 register struct type
*arg_type
= check_typedef (VALUE_TYPE (arg
));
88 register struct type
*type
89 = param_type
? check_typedef (param_type
) : arg_type
;
91 switch (TYPE_CODE (type
))
94 if (TYPE_CODE (arg_type
) != TYPE_CODE_REF
95 && TYPE_CODE (arg_type
) != TYPE_CODE_PTR
)
97 arg
= value_addr (arg
);
98 VALUE_TYPE (arg
) = param_type
;
106 /* If we don't have a prototype, coerce to integer type if necessary. */
109 if (TYPE_LENGTH (type
) < TYPE_LENGTH (builtin_type_int
))
110 type
= builtin_type_int
;
112 /* Currently all target ABIs require at least the width of an integer
113 type for an argument. We may have to conditionalize the following
114 type coercion for future targets. */
115 if (TYPE_LENGTH (type
) < TYPE_LENGTH (builtin_type_int
))
116 type
= builtin_type_int
;
119 if (!is_prototyped
&& coerce_float_to_double_p
)
121 if (TYPE_LENGTH (type
) < TYPE_LENGTH (builtin_type_double
))
122 type
= builtin_type_double
;
123 else if (TYPE_LENGTH (type
) > TYPE_LENGTH (builtin_type_double
))
124 type
= builtin_type_long_double
;
128 type
= lookup_pointer_type (type
);
130 case TYPE_CODE_ARRAY
:
131 /* Arrays are coerced to pointers to their first element, unless
132 they are vectors, in which case we want to leave them alone,
133 because they are passed by value. */
134 if (current_language
->c_style_arrays
)
135 if (!TYPE_VECTOR (type
))
136 type
= lookup_pointer_type (TYPE_TARGET_TYPE (type
));
138 case TYPE_CODE_UNDEF
:
140 case TYPE_CODE_STRUCT
:
141 case TYPE_CODE_UNION
:
144 case TYPE_CODE_RANGE
:
145 case TYPE_CODE_STRING
:
146 case TYPE_CODE_BITSTRING
:
147 case TYPE_CODE_ERROR
:
148 case TYPE_CODE_MEMBER
:
149 case TYPE_CODE_METHOD
:
150 case TYPE_CODE_COMPLEX
:
155 return value_cast (type
, arg
);
158 /* Determine a function's address and its return type from its value.
159 Calls error() if the function is not valid for calling. */
162 find_function_addr (struct value
*function
, struct type
**retval_type
)
164 register struct type
*ftype
= check_typedef (VALUE_TYPE (function
));
165 register enum type_code code
= TYPE_CODE (ftype
);
166 struct type
*value_type
;
169 /* If it's a member function, just look at the function
172 /* Determine address to call. */
173 if (code
== TYPE_CODE_FUNC
|| code
== TYPE_CODE_METHOD
)
175 funaddr
= VALUE_ADDRESS (function
);
176 value_type
= TYPE_TARGET_TYPE (ftype
);
178 else if (code
== TYPE_CODE_PTR
)
180 funaddr
= value_as_address (function
);
181 ftype
= check_typedef (TYPE_TARGET_TYPE (ftype
));
182 if (TYPE_CODE (ftype
) == TYPE_CODE_FUNC
183 || TYPE_CODE (ftype
) == TYPE_CODE_METHOD
)
185 funaddr
= CONVERT_FROM_FUNC_PTR_ADDR (funaddr
);
186 value_type
= TYPE_TARGET_TYPE (ftype
);
189 value_type
= builtin_type_int
;
191 else if (code
== TYPE_CODE_INT
)
193 /* Handle the case of functions lacking debugging info.
194 Their values are characters since their addresses are char */
195 if (TYPE_LENGTH (ftype
) == 1)
196 funaddr
= value_as_address (value_addr (function
));
198 /* Handle integer used as address of a function. */
199 funaddr
= (CORE_ADDR
) value_as_long (function
);
201 value_type
= builtin_type_int
;
204 error ("Invalid data type for function to be called.");
206 *retval_type
= value_type
;
210 /* Call breakpoint_auto_delete on the current contents of the bpstat
211 pointed to by arg (which is really a bpstat *). */
214 breakpoint_auto_delete_contents (void *arg
)
216 breakpoint_auto_delete (*(bpstat
*) arg
);
220 legacy_push_dummy_code (struct gdbarch
*gdbarch
,
221 CORE_ADDR sp
, CORE_ADDR funaddr
, int using_gcc
,
222 struct value
**args
, int nargs
,
223 struct type
*value_type
,
224 CORE_ADDR
*real_pc
, CORE_ADDR
*bp_addr
)
226 /* CALL_DUMMY is an array of words (DEPRECATED_REGISTER_SIZE), but
227 each word is in host byte order. Before calling
228 DEPRECATED_FIX_CALL_DUMMY, we byteswap it and remove any extra
229 bytes which might exist because ULONGEST is bigger than
230 DEPRECATED_REGISTER_SIZE. */
231 /* NOTE: This is pretty wierd, as the call dummy is actually a
232 sequence of instructions. But CISC machines will have to pack
233 the instructions into DEPRECATED_REGISTER_SIZE units (and so will
234 RISC machines for which INSTRUCTION_SIZE is not
235 DEPRECATED_REGISTER_SIZE). */
236 /* NOTE: This is pretty stupid. CALL_DUMMY should be in strict
237 target byte order. */
239 ULONGEST
*dummy
= alloca (DEPRECATED_SIZEOF_CALL_DUMMY_WORDS
);
240 int sizeof_dummy1
= (DEPRECATED_REGISTER_SIZE
241 * DEPRECATED_SIZEOF_CALL_DUMMY_WORDS
242 / sizeof (ULONGEST
));
243 char *dummy1
= alloca (sizeof_dummy1
);
244 memcpy (dummy
, DEPRECATED_CALL_DUMMY_WORDS
,
245 DEPRECATED_SIZEOF_CALL_DUMMY_WORDS
);
246 if (INNER_THAN (1, 2))
248 /* Stack grows down */
258 /* NOTE: cagney/2002-09-10: Don't bother re-adjusting the stack
259 after allocating space for the call dummy. A target can specify
260 a SIZEOF_DUMMY1 (via DEPRECATED_SIZEOF_CALL_DUMMY_WORDS) such
261 that all local alignment requirements are met. */
262 /* Create a call sequence customized for this function and the
263 number of arguments for it. */
266 for (i
= 0; i
< (int) (DEPRECATED_SIZEOF_CALL_DUMMY_WORDS
/ sizeof (dummy
[0]));
268 store_unsigned_integer (&dummy1
[i
* DEPRECATED_REGISTER_SIZE
],
269 DEPRECATED_REGISTER_SIZE
,
270 (ULONGEST
) dummy
[i
]);
272 /* NOTE: cagney/2003-04-22: This computation of REAL_PC, BP_ADDR and
273 DUMMY_ADDR is pretty messed up. It comes from constant tinkering
274 with the values. Instead a DEPRECATED_FIX_CALL_DUMMY replacement
275 (PUSH_DUMMY_BREAKPOINT?) should just do everything. */
276 #ifdef GDB_TARGET_IS_HPPA
277 (*real_pc
) = DEPRECATED_FIX_CALL_DUMMY (dummy1
, start_sp
, funaddr
, nargs
,
278 args
, value_type
, using_gcc
);
280 if (DEPRECATED_FIX_CALL_DUMMY_P ())
282 /* gdb_assert (CALL_DUMMY_LOCATION == ON_STACK) true? */
283 DEPRECATED_FIX_CALL_DUMMY (dummy1
, start_sp
, funaddr
, nargs
, args
,
284 value_type
, using_gcc
);
286 (*real_pc
) = start_sp
;
288 /* Yes, the offset is applied to the real_pc and not the dummy addr.
289 Ulgh! Blame the HP/UX target. */
290 (*bp_addr
) = (*real_pc
) + DEPRECATED_CALL_DUMMY_BREAKPOINT_OFFSET
;
291 /* Yes, the offset is applied to the real_pc and not the
292 dummy_addr. Ulgh! Blame the HP/UX target. */
293 (*real_pc
) += DEPRECATED_CALL_DUMMY_START_OFFSET
;
294 write_memory (start_sp
, (char *) dummy1
, sizeof_dummy1
);
295 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
)
296 generic_save_call_dummy_addr (start_sp
, start_sp
+ sizeof_dummy1
);
301 generic_push_dummy_code (struct gdbarch
*gdbarch
,
302 CORE_ADDR sp
, CORE_ADDR funaddr
, int using_gcc
,
303 struct value
**args
, int nargs
,
304 struct type
*value_type
,
305 CORE_ADDR
*real_pc
, CORE_ADDR
*bp_addr
)
307 /* Something here to findout the size of a breakpoint and then
308 allocate space for it on the stack. */
310 /* This code assumes frame align. */
311 gdb_assert (gdbarch_frame_align_p (gdbarch
));
312 /* Force the stack's alignment. The intent is to ensure that the SP
313 is aligned to at least a breakpoint instruction's boundary. */
314 sp
= gdbarch_frame_align (gdbarch
, sp
);
315 /* Allocate space for, and then position the breakpoint on the
317 if (gdbarch_inner_than (gdbarch
, 1, 2))
320 gdbarch_breakpoint_from_pc (gdbarch
, &bppc
, &bplen
);
321 sp
= gdbarch_frame_align (gdbarch
, sp
- bplen
);
323 /* Should the breakpoint size/location be re-computed here? */
328 gdbarch_breakpoint_from_pc (gdbarch
, bp_addr
, &bplen
);
329 sp
= gdbarch_frame_align (gdbarch
, sp
+ bplen
);
331 /* Inferior resumes at the function entry point. */
332 (*real_pc
) = funaddr
;
336 /* Provide backward compatibility. Once DEPRECATED_FIX_CALL_DUMMY is
337 eliminated, this can be simplified. */
340 push_dummy_code (struct gdbarch
*gdbarch
,
341 CORE_ADDR sp
, CORE_ADDR funaddr
, int using_gcc
,
342 struct value
**args
, int nargs
,
343 struct type
*value_type
,
344 CORE_ADDR
*real_pc
, CORE_ADDR
*bp_addr
)
346 if (gdbarch_push_dummy_code_p (gdbarch
))
347 return gdbarch_push_dummy_code (gdbarch
, sp
, funaddr
, using_gcc
,
348 args
, nargs
, value_type
, real_pc
, bp_addr
);
349 else if (DEPRECATED_FIX_CALL_DUMMY_P ())
350 return legacy_push_dummy_code (gdbarch
, sp
, funaddr
, using_gcc
,
351 args
, nargs
, value_type
, real_pc
, bp_addr
);
353 return generic_push_dummy_code (gdbarch
, sp
, funaddr
, using_gcc
,
354 args
, nargs
, value_type
, real_pc
, bp_addr
);
357 /* All this stuff with a dummy frame may seem unnecessarily complicated
358 (why not just save registers in GDB?). The purpose of pushing a dummy
359 frame which looks just like a real frame is so that if you call a
360 function and then hit a breakpoint (get a signal, etc), "backtrace"
361 will look right. Whether the backtrace needs to actually show the
362 stack at the time the inferior function was called is debatable, but
363 it certainly needs to not display garbage. So if you are contemplating
364 making dummy frames be different from normal frames, consider that. */
366 /* Perform a function call in the inferior.
367 ARGS is a vector of values of arguments (NARGS of them).
368 FUNCTION is a value, the function to be called.
369 Returns a value representing what the function returned.
370 May fail to return, if a breakpoint or signal is hit
371 during the execution of the function.
373 ARGS is modified to contain coerced values. */
376 call_function_by_hand (struct value
*function
, int nargs
, struct value
**args
)
378 register CORE_ADDR sp
;
379 CORE_ADDR dummy_addr
;
380 struct type
*value_type
;
381 unsigned char struct_return
;
382 CORE_ADDR struct_addr
= 0;
383 struct regcache
*retbuf
;
384 struct cleanup
*retbuf_cleanup
;
385 struct inferior_status
*inf_status
;
386 struct cleanup
*inf_status_cleanup
;
388 int using_gcc
; /* Set to version of gcc in use, or zero if not gcc */
390 struct type
*ftype
= check_typedef (SYMBOL_TYPE (function
));
393 if (!target_has_execution
)
396 /* Create a cleanup chain that contains the retbuf (buffer
397 containing the register values). This chain is create BEFORE the
398 inf_status chain so that the inferior status can cleaned up
399 (restored or discarded) without having the retbuf freed. */
400 retbuf
= regcache_xmalloc (current_gdbarch
);
401 retbuf_cleanup
= make_cleanup_regcache_xfree (retbuf
);
403 /* A cleanup for the inferior status. Create this AFTER the retbuf
404 so that this can be discarded or applied without interfering with
406 inf_status
= save_inferior_status (1);
407 inf_status_cleanup
= make_cleanup_restore_inferior_status (inf_status
);
409 if (DEPRECATED_PUSH_DUMMY_FRAME_P ())
411 /* DEPRECATED_PUSH_DUMMY_FRAME is responsible for saving the
412 inferior registers (and frame_pop() for restoring them). (At
413 least on most machines) they are saved on the stack in the
415 DEPRECATED_PUSH_DUMMY_FRAME
;
419 /* FIXME: cagney/2003-02-26: Step zero of this little tinker is
420 to extract the generic dummy frame code from the architecture
421 vector. Hence this direct call.
423 A follow-on change is to modify this interface so that it takes
424 thread OR frame OR ptid as a parameter, and returns a dummy
425 frame handle. The handle can then be used further down as a
426 parameter to generic_save_dummy_frame_tos(). Hmm, thinking
427 about it, since everything is ment to be using generic dummy
428 frames, why not even use some of the dummy frame code to here -
429 do a regcache dup and then pass the duped regcache, along with
430 all the other stuff, at one single point.
432 In fact, you can even save the structure's return address in the
433 dummy frame and fix one of those nasty lost struct return edge
435 generic_push_dummy_frame ();
438 /* Ensure that the initial SP is correctly aligned. */
440 CORE_ADDR old_sp
= read_sp ();
441 if (gdbarch_frame_align_p (current_gdbarch
))
443 /* NOTE: cagney/2002-09-18:
445 On a RISC architecture, a void parameterless generic dummy
446 frame (i.e., no parameters, no result) typically does not
447 need to push anything the stack and hence can leave SP and
448 FP. Similarly, a frameless (possibly leaf) function does
449 not push anything on the stack and, hence, that too can
450 leave FP and SP unchanged. As a consequence, a sequence of
451 void parameterless generic dummy frame calls to frameless
452 functions will create a sequence of effectively identical
453 frames (SP, FP and TOS and PC the same). This, not
454 suprisingly, results in what appears to be a stack in an
455 infinite loop --- when GDB tries to find a generic dummy
456 frame on the internal dummy frame stack, it will always
459 To avoid this problem, the code below always grows the
460 stack. That way, two dummy frames can never be identical.
461 It does burn a few bytes of stack but that is a small price
463 sp
= gdbarch_frame_align (current_gdbarch
, old_sp
);
466 if (INNER_THAN (1, 2))
467 /* Stack grows down. */
468 sp
= gdbarch_frame_align (current_gdbarch
, old_sp
- 1);
470 /* Stack grows up. */
471 sp
= gdbarch_frame_align (current_gdbarch
, old_sp
+ 1);
473 gdb_assert ((INNER_THAN (1, 2) && sp
<= old_sp
)
474 || (INNER_THAN (2, 1) && sp
>= old_sp
));
477 /* FIXME: cagney/2002-09-18: Hey, you loose!
479 Who knows how badly aligned the SP is! Further, per comment
480 above, if the generic dummy frame ends up empty (because
481 nothing is pushed) GDB won't be able to correctly perform
482 back traces. If a target is having trouble with backtraces,
483 first thing to do is add FRAME_ALIGN() to the architecture
484 vector. If that fails, try unwind_dummy_id(). */
488 funaddr
= find_function_addr (function
, &value_type
);
489 CHECK_TYPEDEF (value_type
);
492 struct block
*b
= block_for_pc (funaddr
);
493 /* If compiled without -g, assume GCC 2. */
494 using_gcc
= (b
== NULL
? 2 : BLOCK_GCC_COMPILED (b
));
497 /* Are we returning a value using a structure return or a normal
500 struct_return
= using_struct_return (function
, funaddr
, value_type
,
503 /* Determine the location of the breakpoint (and possibly other
504 stuff) that the called function will return to. The SPARC, for a
505 function returning a structure or union, needs to make space for
506 not just the breakpoint but also an extra word containing the
507 size (?) of the structure being passed. */
509 /* The actual breakpoint (at BP_ADDR) is inserted separatly so there
510 is no need to write that out. */
512 switch (CALL_DUMMY_LOCATION
)
515 /* "dummy_addr" is here just to keep old targets happy. New
516 targets return that same information via "sp" and "bp_addr". */
517 if (INNER_THAN (1, 2))
519 sp
= push_dummy_code (current_gdbarch
, sp
, funaddr
,
520 using_gcc
, args
, nargs
, value_type
,
527 sp
= push_dummy_code (current_gdbarch
, sp
, funaddr
,
528 using_gcc
, args
, nargs
, value_type
,
533 if (DEPRECATED_FIX_CALL_DUMMY_P ())
535 /* Sigh. Some targets use DEPRECATED_FIX_CALL_DUMMY to
536 shove extra stuff onto the stack or into registers. That
537 code should be in PUSH_DUMMY_CALL, however, in the mean
539 /* If the target is manipulating DUMMY1, it looses big time. */
541 DEPRECATED_FIX_CALL_DUMMY (dummy1
, sp
, funaddr
, nargs
, args
,
542 value_type
, using_gcc
);
545 dummy_addr
= CALL_DUMMY_ADDRESS ();
546 /* A call dummy always consists of just a single breakpoint, so
547 it's address is the same as the address of the dummy. */
548 bp_addr
= dummy_addr
;
551 /* Some executables define a symbol __CALL_DUMMY_ADDRESS whose
552 address is the location where the breakpoint should be
553 placed. Once all targets are using the overhauled frame code
554 this can be deleted - ON_STACK is a better option. */
556 struct minimal_symbol
*sym
;
558 sym
= lookup_minimal_symbol ("__CALL_DUMMY_ADDRESS", NULL
, NULL
);
561 dummy_addr
= SYMBOL_VALUE_ADDRESS (sym
);
563 dummy_addr
= entry_point_address ();
564 bp_addr
= dummy_addr
;
568 internal_error (__FILE__
, __LINE__
, "bad switch");
571 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
)
572 /* Save where the breakpoint is going to be inserted so that the
573 dummy-frame code is later able to re-identify it. */
574 generic_save_call_dummy_addr (bp_addr
, bp_addr
+ 1);
576 if (nargs
< TYPE_NFIELDS (ftype
))
577 error ("too few arguments in function call");
581 for (i
= nargs
- 1; i
>= 0; i
--)
584 struct type
*param_type
;
586 /* FIXME drow/2002-05-31: Should just always mark methods as
587 prototyped. Can we respect TYPE_VARARGS? Probably not. */
588 if (TYPE_CODE (ftype
) == TYPE_CODE_METHOD
)
590 else if (i
< TYPE_NFIELDS (ftype
))
591 prototyped
= TYPE_PROTOTYPED (ftype
);
595 if (i
< TYPE_NFIELDS (ftype
))
596 param_type
= TYPE_FIELD_TYPE (ftype
, i
);
600 args
[i
] = value_arg_coerce (args
[i
], param_type
, prototyped
);
602 /* elz: this code is to handle the case in which the function
603 to be called has a pointer to function as parameter and the
604 corresponding actual argument is the address of a function
605 and not a pointer to function variable. In aCC compiled
606 code, the calls through pointers to functions (in the body
607 of the function called by hand) are made via
608 $$dyncall_external which requires some registers setting,
609 this is taken care of if we call via a function pointer
610 variable, but not via a function address. In cc this is
615 if (param_type
!= NULL
&& TYPE_CODE (ftype
) != TYPE_CODE_METHOD
)
617 /* if this parameter is a pointer to function. */
618 if (TYPE_CODE (param_type
) == TYPE_CODE_PTR
)
619 if (TYPE_CODE (TYPE_TARGET_TYPE (param_type
)) == TYPE_CODE_FUNC
)
620 /* elz: FIXME here should go the test about the
621 compiler used to compile the target. We want to
622 issue the error message only if the compiler
623 used was HP's aCC. If we used HP's cc, then
624 there is no problem and no need to return at
626 /* Go see if the actual parameter is a variable of
627 type pointer to function or just a function. */
628 if (args
[i
]->lval
== not_lval
)
631 if (find_pc_partial_function ((CORE_ADDR
) args
[i
]->aligner
.contents
[0], &arg_name
, NULL
, NULL
))
633 You cannot use function <%s> as argument. \n\
634 You must use a pointer to function type variable. Command ignored.", arg_name
);
641 if (REG_STRUCT_HAS_ADDR_P ())
644 /* This is a machine like the sparc, where we may need to pass a
645 pointer to the structure, not the structure itself. */
646 for (i
= nargs
- 1; i
>= 0; i
--)
648 struct type
*arg_type
= check_typedef (VALUE_TYPE (args
[i
]));
649 if ((TYPE_CODE (arg_type
) == TYPE_CODE_STRUCT
650 || TYPE_CODE (arg_type
) == TYPE_CODE_UNION
651 || TYPE_CODE (arg_type
) == TYPE_CODE_ARRAY
652 || TYPE_CODE (arg_type
) == TYPE_CODE_STRING
653 || TYPE_CODE (arg_type
) == TYPE_CODE_BITSTRING
654 || TYPE_CODE (arg_type
) == TYPE_CODE_SET
655 || (TYPE_CODE (arg_type
) == TYPE_CODE_FLT
656 && TYPE_LENGTH (arg_type
) > 8)
658 && REG_STRUCT_HAS_ADDR (using_gcc
, arg_type
))
661 int len
; /* = TYPE_LENGTH (arg_type); */
663 arg_type
= check_typedef (VALUE_ENCLOSING_TYPE (args
[i
]));
664 len
= TYPE_LENGTH (arg_type
);
666 if (STACK_ALIGN_P ())
667 /* MVS 11/22/96: I think at least some of this
668 stack_align code is really broken. Better to let
669 PUSH_ARGUMENTS adjust the stack in a target-defined
671 aligned_len
= STACK_ALIGN (len
);
674 if (INNER_THAN (1, 2))
676 /* stack grows downward */
678 /* ... so the address of the thing we push is the
679 stack pointer after we push it. */
684 /* The stack grows up, so the address of the thing
685 we push is the stack pointer before we push it. */
689 /* Push the structure. */
690 write_memory (addr
, VALUE_CONTENTS_ALL (args
[i
]), len
);
691 /* The value we're going to pass is the address of the
692 thing we just pushed. */
693 /*args[i] = value_from_longest (lookup_pointer_type (value_type),
695 args
[i
] = value_from_pointer (lookup_pointer_type (arg_type
),
702 /* Reserve space for the return structure to be written on the
703 stack, if necessary. Make certain that the value is correctly
708 int len
= TYPE_LENGTH (value_type
);
709 if (STACK_ALIGN_P ())
710 /* NOTE: cagney/2003-03-22: Should rely on frame align, rather
711 than stack align to force the alignment of the stack. */
712 len
= STACK_ALIGN (len
);
713 if (INNER_THAN (1, 2))
715 /* Stack grows downward. Align STRUCT_ADDR and SP after
716 making space for the return value. */
718 if (gdbarch_frame_align_p (current_gdbarch
))
719 sp
= gdbarch_frame_align (current_gdbarch
, sp
);
724 /* Stack grows upward. Align the frame, allocate space, and
725 then again, re-align the frame??? */
726 if (gdbarch_frame_align_p (current_gdbarch
))
727 sp
= gdbarch_frame_align (current_gdbarch
, sp
);
730 if (gdbarch_frame_align_p (current_gdbarch
))
731 sp
= gdbarch_frame_align (current_gdbarch
, sp
);
735 /* elz: on HPPA no need for this extra alignment, maybe it is needed
736 on other architectures. This is because all the alignment is
737 taken care of in the above code (ifdef REG_STRUCT_HAS_ADDR) and
738 in hppa_push_arguments */
739 /* NOTE: cagney/2003-03-24: The below code is very broken. Given an
740 odd sized parameter the below will mis-align the stack. As was
741 suggested back in '96, better to let PUSH_ARGUMENTS handle it. */
742 if (DEPRECATED_EXTRA_STACK_ALIGNMENT_NEEDED
)
744 /* MVS 11/22/96: I think at least some of this stack_align code
745 is really broken. Better to let push_dummy_call() adjust the
746 stack in a target-defined manner. */
747 if (STACK_ALIGN_P () && INNER_THAN (1, 2))
749 /* If stack grows down, we must leave a hole at the top. */
752 for (i
= nargs
- 1; i
>= 0; i
--)
753 len
+= TYPE_LENGTH (VALUE_ENCLOSING_TYPE (args
[i
]));
754 if (DEPRECATED_CALL_DUMMY_STACK_ADJUST_P ())
755 len
+= DEPRECATED_CALL_DUMMY_STACK_ADJUST
;
756 sp
-= STACK_ALIGN (len
) - len
;
760 /* Create the dummy stack frame. Pass in the call dummy address as,
761 presumably, the ABI code knows where, in the call dummy, the
762 return address should be pointed. */
763 if (gdbarch_push_dummy_call_p (current_gdbarch
))
764 /* When there is no push_dummy_call method, should this code
765 simply error out. That would the implementation of this method
766 for all ABIs (which is probably a good thing). */
767 sp
= gdbarch_push_dummy_call (current_gdbarch
, funaddr
, current_regcache
,
768 bp_addr
, nargs
, args
, sp
, struct_return
,
770 else if (DEPRECATED_PUSH_ARGUMENTS_P ())
771 /* Keep old targets working. */
772 sp
= DEPRECATED_PUSH_ARGUMENTS (nargs
, args
, sp
, struct_return
,
775 sp
= legacy_push_arguments (nargs
, args
, sp
, struct_return
, struct_addr
);
777 if (DEPRECATED_PUSH_RETURN_ADDRESS_P ())
778 /* for targets that use no CALL_DUMMY */
779 /* There are a number of targets now which actually don't write
780 any CALL_DUMMY instructions into the target, but instead just
781 save the machine state, push the arguments, and jump directly
782 to the callee function. Since this doesn't actually involve
783 executing a JSR/BSR instruction, the return address must be set
784 up by hand, either by pushing onto the stack or copying into a
785 return-address register as appropriate. Formerly this has been
786 done in PUSH_ARGUMENTS, but that's overloading its
787 functionality a bit, so I'm making it explicit to do it here. */
788 /* NOTE: cagney/2003-04-22: The first parameter ("real_pc") has
789 been replaced with zero, it turns out that no implementation
790 used that parameter. This occured because the value being
791 supplied - the address of the called function's entry point
792 instead of the address of the breakpoint that the called
793 function should return to - wasn't useful. */
794 sp
= DEPRECATED_PUSH_RETURN_ADDRESS (0, sp
);
796 /* NOTE: cagney/2003-03-23: Diable this code when there is a
797 push_dummy_call() method. Since that method will have already
798 handled any alignment issues, the code below is entirely
800 if (!gdbarch_push_dummy_call_p (current_gdbarch
)
801 && STACK_ALIGN_P () && !INNER_THAN (1, 2))
803 /* If stack grows up, we must leave a hole at the bottom, note
804 that sp already has been advanced for the arguments! */
805 if (DEPRECATED_CALL_DUMMY_STACK_ADJUST_P ())
806 sp
+= DEPRECATED_CALL_DUMMY_STACK_ADJUST
;
807 sp
= STACK_ALIGN (sp
);
810 /* XXX This seems wrong. For stacks that grow down we shouldn't do
812 /* MVS 11/22/96: I think at least some of this stack_align code is
813 really broken. Better to let PUSH_ARGUMENTS adjust the stack in
814 a target-defined manner. */
815 if (DEPRECATED_CALL_DUMMY_STACK_ADJUST_P ())
816 if (INNER_THAN (1, 2))
818 /* stack grows downward */
819 sp
-= DEPRECATED_CALL_DUMMY_STACK_ADJUST
;
822 /* Store the address at which the structure is supposed to be
824 /* NOTE: 2003-03-24: Since PUSH_ARGUMENTS can (and typically does)
825 store the struct return address, this call is entirely redundant. */
826 if (struct_return
&& DEPRECATED_STORE_STRUCT_RETURN_P ())
827 DEPRECATED_STORE_STRUCT_RETURN (struct_addr
, sp
);
829 /* Write the stack pointer. This is here because the statements
830 above might fool with it. On SPARC, this write also stores the
831 register window into the right place in the new stack frame,
832 which otherwise wouldn't happen (see store_inferior_registers in
834 /* NOTE: cagney/2003-03-23: Since the architecture method
835 push_dummy_call() should have already stored the stack pointer
836 (as part of creating the fake call frame), and none of the code
837 following that call adjusts the stack-pointer value, the below
838 call is entirely redundant. */
839 if (DEPRECATED_DUMMY_WRITE_SP_P ())
840 DEPRECATED_DUMMY_WRITE_SP (sp
);
842 if (gdbarch_unwind_dummy_id_p (current_gdbarch
))
844 /* Sanity. The exact same SP value is returned by
845 PUSH_DUMMY_CALL, saved as the dummy-frame TOS, and used by
846 unwind_dummy_id to form the frame ID's stack address. */
847 gdb_assert (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
);
848 generic_save_dummy_frame_tos (sp
);
850 else if (DEPRECATED_SAVE_DUMMY_FRAME_TOS_P ())
851 DEPRECATED_SAVE_DUMMY_FRAME_TOS (sp
);
853 /* Now proceed, having reached the desired place. */
854 clear_proceed_status ();
856 /* Create a momentary breakpoint at the return address of the
857 inferior. That way it breaks when it returns. */
860 struct breakpoint
*bpt
;
861 struct symtab_and_line sal
;
862 struct frame_id frame
;
863 init_sal (&sal
); /* initialize to zeroes */
865 sal
.section
= find_pc_overlay (sal
.pc
);
866 /* Set up a frame ID for the dummy frame so we can pass it to
867 set_momentary_breakpoint. We need to give the breakpoint a
868 frame ID so that the breakpoint code can correctly re-identify
869 the dummy breakpoint. */
870 if (gdbarch_unwind_dummy_id_p (current_gdbarch
))
872 /* Sanity. The exact same SP value is returned by
873 PUSH_DUMMY_CALL, saved as the dummy-frame TOS, and used by
874 unwind_dummy_id to form the frame ID's stack address. */
875 gdb_assert (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
);
876 frame
= frame_id_build (sp
, sal
.pc
);
880 /* The assumption here is that push_dummy_call() returned the
881 stack part of the frame ID. Unfortunatly, many older
882 architectures were, via a convoluted mess, relying on the
883 poorly defined and greatly overloaded
884 DEPRECATED_TARGET_READ_FP or DEPRECATED_FP_REGNUM to supply
886 if (DEPRECATED_TARGET_READ_FP_P ())
887 frame
= frame_id_build (DEPRECATED_TARGET_READ_FP (), sal
.pc
);
888 else if (DEPRECATED_FP_REGNUM
>= 0)
889 frame
= frame_id_build (read_register (DEPRECATED_FP_REGNUM
), sal
.pc
);
891 frame
= frame_id_build (sp
, sal
.pc
);
893 bpt
= set_momentary_breakpoint (sal
, frame
, bp_call_dummy
);
894 bpt
->disposition
= disp_del
;
897 /* Execute a "stack dummy", a piece of code stored in the stack by
898 the debugger to be executed in the inferior.
900 The dummy's frame is automatically popped whenever that break is
901 hit. If that is the first time the program stops,
902 call_function_by_hand returns to its caller with that frame
903 already gone and sets RC to 0.
905 Otherwise, set RC to a non-zero value. If the called function
906 receives a random signal, we do not allow the user to continue
907 executing it as this may not work. The dummy frame is poped and
908 we return 1. If we hit a breakpoint, we leave the frame in place
909 and return 2 (the frame will eventually be popped when we do hit
910 the dummy end breakpoint). */
913 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, 0);
916 /* If all error()s out of proceed ended up calling normal_stop
917 (and perhaps they should; it already does in the special case
918 of error out of resume()), then we wouldn't need this. */
919 make_cleanup (breakpoint_auto_delete_contents
, &stop_bpstat
);
921 disable_watchpoints_before_interactive_call_start ();
922 proceed_to_finish
= 1; /* We want stop_registers, please... */
924 if (target_can_async_p ())
925 saved_async
= target_async_mask (0);
927 proceed (real_pc
, TARGET_SIGNAL_0
, 0);
930 target_async_mask (saved_async
);
932 enable_watchpoints_after_interactive_call_stop ();
934 discard_cleanups (old_cleanups
);
937 if (stopped_by_random_signal
|| !stop_stack_dummy
)
939 /* Find the name of the function we're about to complain about. */
940 const char *name
= NULL
;
942 struct symbol
*symbol
= find_pc_function (funaddr
);
944 name
= SYMBOL_PRINT_NAME (symbol
);
947 /* Try the minimal symbols. */
948 struct minimal_symbol
*msymbol
= lookup_minimal_symbol_by_pc (funaddr
);
950 name
= SYMBOL_PRINT_NAME (msymbol
);
954 /* Can't use a cleanup here. It is discarded, instead use
956 char *tmp
= xstrprintf ("at %s", local_hex_string (funaddr
));
957 char *a
= alloca (strlen (tmp
) + 1);
963 if (stopped_by_random_signal
)
965 /* We stopped inside the FUNCTION because of a random
966 signal. Further execution of the FUNCTION is not
969 if (unwind_on_signal_p
)
971 /* The user wants the context restored. */
973 /* We must get back to the frame we were before the
975 frame_pop (get_current_frame ());
977 /* FIXME: Insert a bunch of wrap_here; name can be very
978 long if it's a C++ name with arguments and stuff. */
980 The program being debugged was signaled while in a function called from GDB.\n\
981 GDB has restored the context to what it was before the call.\n\
982 To change this behavior use \"set unwindonsignal off\"\n\
983 Evaluation of the expression containing the function (%s) will be abandoned.",
988 /* The user wants to stay in the frame where we stopped
990 /* If we restored the inferior status (via the cleanup),
991 we would print a spurious error message (Unable to
992 restore previously selected frame), would write the
993 registers from the inf_status (which is wrong), and
994 would do other wrong things. */
995 discard_cleanups (inf_status_cleanup
);
996 discard_inferior_status (inf_status
);
997 /* FIXME: Insert a bunch of wrap_here; name can be very
998 long if it's a C++ name with arguments and stuff. */
1000 The program being debugged was signaled while in a function called from GDB.\n\
1001 GDB remains in the frame where the signal was received.\n\
1002 To change this behavior use \"set unwindonsignal on\"\n\
1003 Evaluation of the expression containing the function (%s) will be abandoned.",
1008 if (!stop_stack_dummy
)
1010 /* We hit a breakpoint inside the FUNCTION. */
1011 /* If we restored the inferior status (via the cleanup), we
1012 would print a spurious error message (Unable to restore
1013 previously selected frame), would write the registers
1014 from the inf_status (which is wrong), and would do other
1016 discard_cleanups (inf_status_cleanup
);
1017 discard_inferior_status (inf_status
);
1018 /* The following error message used to say "The expression
1019 which contained the function call has been discarded."
1020 It is a hard concept to explain in a few words. Ideally,
1021 GDB would be able to resume evaluation of the expression
1022 when the function finally is done executing. Perhaps
1023 someday this will be implemented (it would not be easy). */
1024 /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
1025 a C++ name with arguments and stuff. */
1027 The program being debugged stopped while in a function called from GDB.\n\
1028 When the function (%s) is done executing, GDB will silently\n\
1029 stop (instead of continuing to evaluate the expression containing\n\
1030 the function call).", name
);
1033 /* The above code errors out, so ... */
1034 internal_error (__FILE__
, __LINE__
, "... should not be here");
1037 /* If we get here the called FUNCTION run to completion. */
1039 /* On normal return, the stack dummy has been popped already. */
1040 regcache_cpy_no_passthrough (retbuf
, stop_registers
);
1042 /* Restore the inferior status, via its cleanup. At this stage,
1043 leave the RETBUF alone. */
1044 do_cleanups (inf_status_cleanup
);
1046 /* Figure out the value returned by the function. */
1047 /* elz: I defined this new macro for the hppa architecture only.
1048 this gives us a way to get the value returned by the function
1049 from the stack, at the same address we told the function to put
1050 it. We cannot assume on the pa that r28 still contains the
1051 address of the returned structure. Usually this will be
1052 overwritten by the callee. I don't know about other
1053 architectures, so I defined this macro */
1054 #ifdef VALUE_RETURNED_FROM_STACK
1057 do_cleanups (retbuf_cleanup
);
1058 return VALUE_RETURNED_FROM_STACK (value_type
, struct_addr
);
1061 /* NOTE: cagney/2002-09-10: Only when the stack has been correctly
1062 aligned (using frame_align()) do we can trust STRUCT_ADDR and
1063 fetch the return value direct from the stack. This lack of trust
1064 comes about because legacy targets have a nasty habit of
1065 silently, and local to PUSH_ARGUMENTS(), moving STRUCT_ADDR. For
1066 such targets, just hope that value_being_returned() can find the
1068 if (struct_return
&& gdbarch_frame_align_p (current_gdbarch
))
1070 struct value
*retval
= value_at (value_type
, struct_addr
, NULL
);
1071 do_cleanups (retbuf_cleanup
);
1076 struct value
*retval
= value_being_returned (value_type
, retbuf
,
1078 do_cleanups (retbuf_cleanup
);
1083 void _initialize_infcall (void);
1086 _initialize_infcall (void)
1088 add_setshow_boolean_cmd ("coerce-float-to-double", class_obscure
,
1089 &coerce_float_to_double_p
, "\
1090 Set coercion of floats to doubles when calling functions\n\
1091 Variables of type float should generally be converted to doubles before\n\
1092 calling an unprototyped function, and left alone when calling a prototyped\n\
1093 function. However, some older debug info formats do not provide enough\n\
1094 information to determine that a function is prototyped. If this flag is\n\
1095 set, GDB will perform the conversion for a function it considers\n\
1097 The default is to perform the conversion.\n", "\
1098 Show coercion of floats to doubles when calling functions\n\
1099 Variables of type float should generally be converted to doubles before\n\
1100 calling an unprototyped function, and left alone when calling a prototyped\n\
1101 function. However, some older debug info formats do not provide enough\n\
1102 information to determine that a function is prototyped. If this flag is\n\
1103 set, GDB will perform the conversion for a function it considers\n\
1105 The default is to perform the conversion.\n",
1106 NULL
, NULL
, &setlist
, &showlist
);
1108 add_setshow_boolean_cmd ("unwindonsignal", no_class
,
1109 &unwind_on_signal_p
, "\
1110 Set unwinding of stack if a signal is received while in a call dummy.\n\
1111 The unwindonsignal lets the user determine what gdb should do if a signal\n\
1112 is received while in a function called from gdb (call dummy). If set, gdb\n\
1113 unwinds the stack and restore the context to what as it was before the call.\n\
1114 The default is to stop in the frame where the signal was received.", "\
1115 Set unwinding of stack if a signal is received while in a call dummy.\n\
1116 The unwindonsignal lets the user determine what gdb should do if a signal\n\
1117 is received while in a function called from gdb (call dummy). If set, gdb\n\
1118 unwinds the stack and restore the context to what as it was before the call.\n\
1119 The default is to stop in the frame where the signal was received.",
1120 NULL
, NULL
, &setlist
, &showlist
);