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04714b91 AC |
1 | /* Perform an inferior function call, for GDB, the GNU debugger. |
2 | ||
3 | Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, | |
4 | 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Free Software | |
5 | Foundation, Inc. | |
6 | ||
7 | This file is part of GDB. | |
8 | ||
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. | |
13 | ||
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. | |
18 | ||
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. */ | |
23 | ||
24 | #include "defs.h" | |
25 | #include "breakpoint.h" | |
26 | #include "target.h" | |
27 | #include "regcache.h" | |
28 | #include "inferior.h" | |
29 | #include "gdb_assert.h" | |
30 | #include "block.h" | |
31 | #include "gdbcore.h" | |
32 | #include "language.h" | |
33 | #include "symfile.h" | |
34 | #include "gdbcmd.h" | |
35 | #include "command.h" | |
36 | #include "gdb_string.h" | |
37 | ||
38 | /* NOTE: cagney/2003-04-16: What's the future of this code? | |
39 | ||
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. */ | |
43 | ||
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. | |
50 | ||
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 | |
56 | decide what to do. | |
57 | ||
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". */ | |
64 | ||
65 | static int coerce_float_to_double_p = 1; | |
66 | ||
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 | |
70 | call. | |
71 | ||
72 | The default is to stop in the frame where the signal was received. */ | |
73 | ||
74 | int unwind_on_signal_p = 0; | |
75 | ||
76 | /* Perform the standard coercions that are specified | |
77 | for arguments to be passed to C functions. | |
78 | ||
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. */ | |
81 | ||
82 | static struct value * | |
83 | value_arg_coerce (struct value *arg, struct type *param_type, | |
84 | int is_prototyped) | |
85 | { | |
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; | |
89 | ||
90 | switch (TYPE_CODE (type)) | |
91 | { | |
92 | case TYPE_CODE_REF: | |
93 | if (TYPE_CODE (arg_type) != TYPE_CODE_REF | |
94 | && TYPE_CODE (arg_type) != TYPE_CODE_PTR) | |
95 | { | |
96 | arg = value_addr (arg); | |
97 | VALUE_TYPE (arg) = param_type; | |
98 | return arg; | |
99 | } | |
100 | break; | |
101 | case TYPE_CODE_INT: | |
102 | case TYPE_CODE_CHAR: | |
103 | case TYPE_CODE_BOOL: | |
104 | case TYPE_CODE_ENUM: | |
105 | /* If we don't have a prototype, coerce to integer type if necessary. */ | |
106 | if (!is_prototyped) | |
107 | { | |
108 | if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int)) | |
109 | type = builtin_type_int; | |
110 | } | |
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; | |
116 | break; | |
117 | case TYPE_CODE_FLT: | |
118 | if (!is_prototyped && coerce_float_to_double_p) | |
119 | { | |
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; | |
124 | } | |
125 | break; | |
126 | case TYPE_CODE_FUNC: | |
127 | type = lookup_pointer_type (type); | |
128 | break; | |
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)); | |
136 | break; | |
137 | case TYPE_CODE_UNDEF: | |
138 | case TYPE_CODE_PTR: | |
139 | case TYPE_CODE_STRUCT: | |
140 | case TYPE_CODE_UNION: | |
141 | case TYPE_CODE_VOID: | |
142 | case TYPE_CODE_SET: | |
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: | |
150 | default: | |
151 | break; | |
152 | } | |
153 | ||
154 | return value_cast (type, arg); | |
155 | } | |
156 | ||
157 | /* Determine a function's address and its return type from its value. | |
158 | Calls error() if the function is not valid for calling. */ | |
159 | ||
160 | static CORE_ADDR | |
161 | find_function_addr (struct value *function, struct type **retval_type) | |
162 | { | |
163 | register struct type *ftype = check_typedef (VALUE_TYPE (function)); | |
164 | register enum type_code code = TYPE_CODE (ftype); | |
165 | struct type *value_type; | |
166 | CORE_ADDR funaddr; | |
167 | ||
168 | /* If it's a member function, just look at the function | |
169 | part of it. */ | |
170 | ||
171 | /* Determine address to call. */ | |
172 | if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD) | |
173 | { | |
174 | funaddr = VALUE_ADDRESS (function); | |
175 | value_type = TYPE_TARGET_TYPE (ftype); | |
176 | } | |
177 | else if (code == TYPE_CODE_PTR) | |
178 | { | |
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) | |
183 | { | |
184 | funaddr = CONVERT_FROM_FUNC_PTR_ADDR (funaddr); | |
185 | value_type = TYPE_TARGET_TYPE (ftype); | |
186 | } | |
187 | else | |
188 | value_type = builtin_type_int; | |
189 | } | |
190 | else if (code == TYPE_CODE_INT) | |
191 | { | |
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)); | |
196 | else | |
197 | /* Handle integer used as address of a function. */ | |
198 | funaddr = (CORE_ADDR) value_as_long (function); | |
199 | ||
200 | value_type = builtin_type_int; | |
201 | } | |
202 | else | |
203 | error ("Invalid data type for function to be called."); | |
204 | ||
205 | *retval_type = value_type; | |
206 | return funaddr; | |
207 | } | |
208 | ||
209 | /* Call breakpoint_auto_delete on the current contents of the bpstat | |
210 | pointed to by arg (which is really a bpstat *). */ | |
211 | ||
212 | static void | |
213 | breakpoint_auto_delete_contents (void *arg) | |
214 | { | |
215 | breakpoint_auto_delete (*(bpstat *) arg); | |
216 | } | |
217 | ||
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. */ | |
226 | ||
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. | |
233 | ||
234 | ARGS is modified to contain coerced values. */ | |
235 | ||
236 | struct value * | |
237 | call_function_by_hand (struct value *function, int nargs, struct value **args) | |
238 | { | |
239 | register CORE_ADDR sp; | |
240 | register int i; | |
241 | int rc; | |
242 | CORE_ADDR start_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. | |
247 | ||
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 | |
252 | REGISTER_SIZE). | |
253 | ||
254 | NOTE: This is pretty stupid. CALL_DUMMY should be in strict | |
255 | target byte order. */ | |
256 | ||
257 | static ULONGEST *dummy; | |
258 | int sizeof_dummy1; | |
259 | char *dummy1; | |
260 | CORE_ADDR dummy_addr; | |
261 | CORE_ADDR old_sp; | |
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; | |
269 | CORE_ADDR funaddr; | |
270 | int using_gcc; /* Set to version of gcc in use, or zero if not gcc */ | |
271 | CORE_ADDR real_pc; | |
272 | struct type *param_type = NULL; | |
273 | struct type *ftype = check_typedef (SYMBOL_TYPE (function)); | |
274 | int n_method_args = 0; | |
275 | ||
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); | |
280 | ||
281 | if (!target_has_execution) | |
282 | noprocess (); | |
283 | ||
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); | |
290 | ||
291 | /* A cleanup for the inferior status. Create this AFTER the retbuf | |
292 | so that this can be discarded or applied without interfering with | |
293 | the regbuf. */ | |
294 | inf_status = save_inferior_status (1); | |
295 | inf_status_cleanup = make_cleanup_restore_inferior_status (inf_status); | |
296 | ||
297 | if (DEPRECATED_PUSH_DUMMY_FRAME_P ()) | |
298 | { | |
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 | |
302 | inferior. */ | |
303 | DEPRECATED_PUSH_DUMMY_FRAME; | |
304 | } | |
305 | else | |
306 | { | |
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. | |
310 | ||
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. | |
319 | ||
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 | |
322 | conditions. */ | |
323 | generic_push_dummy_frame (); | |
324 | } | |
325 | ||
326 | old_sp = read_sp (); | |
327 | ||
328 | /* Ensure that the initial SP is correctly aligned. */ | |
329 | if (gdbarch_frame_align_p (current_gdbarch)) | |
330 | { | |
331 | /* NOTE: cagney/2002-09-18: | |
332 | ||
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 | |
345 | the first one. | |
346 | ||
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 | |
350 | :-). */ | |
351 | sp = gdbarch_frame_align (current_gdbarch, old_sp); | |
352 | if (sp == old_sp) | |
353 | { | |
354 | if (INNER_THAN (1, 2)) | |
355 | /* Stack grows down. */ | |
356 | sp = gdbarch_frame_align (current_gdbarch, old_sp - 1); | |
357 | else | |
358 | /* Stack grows up. */ | |
359 | sp = gdbarch_frame_align (current_gdbarch, old_sp + 1); | |
360 | } | |
361 | gdb_assert ((INNER_THAN (1, 2) && sp <= old_sp) | |
362 | || (INNER_THAN (2, 1) && sp >= old_sp)); | |
363 | } | |
364 | else | |
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. */ | |
374 | sp = old_sp; | |
375 | ||
376 | if (INNER_THAN (1, 2)) | |
377 | { | |
378 | /* Stack grows down */ | |
379 | sp -= sizeof_dummy1; | |
380 | start_sp = sp; | |
381 | } | |
382 | else | |
383 | { | |
384 | /* Stack grows up */ | |
385 | start_sp = sp; | |
386 | sp += sizeof_dummy1; | |
387 | } | |
388 | ||
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. */ | |
393 | ||
394 | funaddr = find_function_addr (function, &value_type); | |
395 | CHECK_TYPEDEF (value_type); | |
396 | ||
397 | { | |
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)); | |
401 | } | |
402 | ||
403 | /* Are we returning a value using a structure return or a normal | |
404 | value return? */ | |
405 | ||
406 | struct_return = using_struct_return (function, funaddr, value_type, | |
407 | using_gcc); | |
408 | ||
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], | |
413 | REGISTER_SIZE, | |
414 | (ULONGEST) dummy[i]); | |
415 | ||
416 | #ifdef GDB_TARGET_IS_HPPA | |
417 | real_pc = FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args, | |
418 | value_type, using_gcc); | |
419 | #else | |
420 | if (FIX_CALL_DUMMY_P ()) | |
421 | { | |
422 | /* gdb_assert (CALL_DUMMY_LOCATION == ON_STACK) true? */ | |
423 | FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args, value_type, | |
424 | using_gcc); | |
425 | } | |
426 | real_pc = start_sp; | |
427 | #endif | |
428 | ||
429 | switch (CALL_DUMMY_LOCATION) | |
430 | { | |
431 | case ON_STACK: | |
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); | |
436 | break; | |
437 | case AT_ENTRY_POINT: | |
438 | real_pc = funaddr; | |
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); | |
445 | break; | |
446 | default: | |
447 | internal_error (__FILE__, __LINE__, "bad switch"); | |
448 | } | |
449 | ||
450 | #ifdef lint | |
451 | sp = old_sp; /* It really is used, for some ifdef's... */ | |
452 | #endif | |
453 | ||
454 | if (nargs < TYPE_NFIELDS (ftype)) | |
455 | error ("too few arguments in function call"); | |
456 | ||
457 | for (i = nargs - 1; i >= 0; i--) | |
458 | { | |
459 | int prototyped; | |
460 | ||
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) | |
464 | prototyped = 1; | |
465 | else | |
466 | prototyped = TYPE_PROTOTYPED (ftype); | |
467 | ||
468 | if (i < TYPE_NFIELDS (ftype)) | |
469 | args[i] = value_arg_coerce (args[i], TYPE_FIELD_TYPE (ftype, i), | |
470 | prototyped); | |
471 | else | |
472 | args[i] = value_arg_coerce (args[i], NULL, 0); | |
473 | ||
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. */ | |
482 | ||
483 | if (using_gcc == 0) | |
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) | |
497 | { | |
498 | char *arg_name; | |
499 | if (find_pc_partial_function ((CORE_ADDR) args[i]->aligner.contents[0], &arg_name, NULL, NULL)) | |
500 | error ("\ | |
501 | You cannot use function <%s> as argument. \n\ | |
502 | You must use a pointer to function type variable. Command ignored.", arg_name); | |
503 | } | |
504 | } | |
505 | ||
506 | if (REG_STRUCT_HAS_ADDR_P ()) | |
507 | { | |
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--) | |
511 | { | |
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) | |
521 | ) | |
522 | && REG_STRUCT_HAS_ADDR (using_gcc, arg_type)) | |
523 | { | |
524 | CORE_ADDR addr; | |
525 | int len; /* = TYPE_LENGTH (arg_type); */ | |
526 | int aligned_len; | |
527 | arg_type = check_typedef (VALUE_ENCLOSING_TYPE (args[i])); | |
528 | len = TYPE_LENGTH (arg_type); | |
529 | ||
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 | |
534 | manner. */ | |
535 | aligned_len = STACK_ALIGN (len); | |
536 | else | |
537 | aligned_len = len; | |
538 | if (INNER_THAN (1, 2)) | |
539 | { | |
540 | /* stack grows downward */ | |
541 | sp -= aligned_len; | |
542 | /* ... so the address of the thing we push is the | |
543 | stack pointer after we push it. */ | |
544 | addr = sp; | |
545 | } | |
546 | else | |
547 | { | |
548 | /* The stack grows up, so the address of the thing | |
549 | we push is the stack pointer before we push it. */ | |
550 | addr = sp; | |
551 | sp += aligned_len; | |
552 | } | |
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), | |
558 | (LONGEST) addr); */ | |
559 | args[i] = value_from_pointer (lookup_pointer_type (arg_type), | |
560 | addr); | |
561 | } | |
562 | } | |
563 | } | |
564 | ||
565 | ||
566 | /* Reserve space for the return structure to be written on the | |
567 | stack, if necessary. Make certain that the value is correctly | |
568 | aligned. */ | |
569 | ||
570 | if (struct_return) | |
571 | { | |
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)) | |
578 | { | |
579 | /* Stack grows downward. Align STRUCT_ADDR and SP after | |
580 | making space for the return value. */ | |
581 | sp -= len; | |
582 | if (gdbarch_frame_align_p (current_gdbarch)) | |
583 | sp = gdbarch_frame_align (current_gdbarch, sp); | |
584 | struct_addr = sp; | |
585 | } | |
586 | else | |
587 | { | |
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); | |
592 | struct_addr = sp; | |
593 | sp += len; | |
594 | if (gdbarch_frame_align_p (current_gdbarch)) | |
595 | sp = gdbarch_frame_align (current_gdbarch, sp); | |
596 | } | |
597 | } | |
598 | ||
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) | |
607 | { | |
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)) | |
612 | { | |
613 | /* If stack grows down, we must leave a hole at the top. */ | |
614 | int len = 0; | |
615 | ||
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; | |
621 | } | |
622 | } | |
623 | ||
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, | |
633 | struct_addr); | |
634 | else if (DEPRECATED_PUSH_ARGUMENTS_P ()) | |
635 | /* Keep old targets working. */ | |
636 | sp = DEPRECATED_PUSH_ARGUMENTS (nargs, args, sp, struct_return, | |
637 | struct_addr); | |
638 | else | |
639 | sp = legacy_push_arguments (nargs, args, sp, struct_return, struct_addr); | |
640 | ||
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); | |
653 | ||
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 | |
657 | redundant. */ | |
658 | if (!gdbarch_push_dummy_call_p (current_gdbarch) | |
659 | && STACK_ALIGN_P () && !INNER_THAN (1, 2)) | |
660 | { | |
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); | |
666 | } | |
667 | ||
668 | /* XXX This seems wrong. For stacks that grow down we shouldn't do | |
669 | anything here! */ | |
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)) | |
675 | { | |
676 | /* stack grows downward */ | |
677 | sp -= DEPRECATED_CALL_DUMMY_STACK_ADJUST; | |
678 | } | |
679 | ||
680 | /* Store the address at which the structure is supposed to be | |
681 | written. */ | |
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); | |
686 | ||
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); | |
698 | ||
699 | if (SAVE_DUMMY_FRAME_TOS_P ()) | |
700 | SAVE_DUMMY_FRAME_TOS (sp); | |
701 | ||
702 | { | |
703 | char *name; | |
704 | struct symbol *symbol; | |
705 | ||
706 | name = NULL; | |
707 | symbol = find_pc_function (funaddr); | |
708 | if (symbol) | |
709 | { | |
710 | name = SYMBOL_PRINT_NAME (symbol); | |
711 | } | |
712 | else | |
713 | { | |
714 | /* Try the minimal symbols. */ | |
715 | struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (funaddr); | |
716 | ||
717 | if (msymbol) | |
718 | { | |
719 | name = SYMBOL_PRINT_NAME (msymbol); | |
720 | } | |
721 | } | |
722 | if (name == NULL) | |
723 | { | |
724 | char format[80]; | |
725 | sprintf (format, "at %s", local_hex_format ()); | |
726 | name = alloca (80); | |
727 | /* FIXME-32x64: assumes funaddr fits in a long. */ | |
728 | sprintf (name, format, (unsigned long) funaddr); | |
729 | } | |
730 | ||
731 | { | |
732 | /* Execute a "stack dummy", a piece of code stored in the stack | |
733 | by the debugger to be executed in the inferior. | |
734 | ||
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. | |
739 | ||
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 | |
746 | breakpoint). */ | |
747 | ||
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); | |
751 | int saved_async = 0; | |
752 | struct breakpoint *bpt; | |
753 | struct symtab_and_line sal; | |
754 | ||
755 | /* Now proceed, having reached the desired place. */ | |
756 | clear_proceed_status (); | |
757 | ||
758 | init_sal (&sal); /* initialize to zeroes */ | |
759 | if (CALL_DUMMY_LOCATION == AT_ENTRY_POINT) | |
760 | { | |
761 | sal.pc = CALL_DUMMY_ADDRESS (); | |
762 | } | |
763 | else | |
764 | { | |
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. | |
768 | ||
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)); | |
774 | } | |
775 | sal.section = find_pc_overlay (sal.pc); | |
776 | ||
777 | { | |
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; | |
787 | } | |
788 | ||
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); | |
793 | ||
794 | disable_watchpoints_before_interactive_call_start (); | |
795 | proceed_to_finish = 1; /* We want stop_registers, please... */ | |
796 | ||
797 | if (target_can_async_p ()) | |
798 | saved_async = target_async_mask (0); | |
799 | ||
800 | proceed (addr, TARGET_SIGNAL_0, 0); | |
801 | ||
802 | if (saved_async) | |
803 | target_async_mask (saved_async); | |
804 | ||
805 | enable_watchpoints_after_interactive_call_stop (); | |
806 | ||
807 | discard_cleanups (old_cleanups); | |
808 | ||
809 | if (stopped_by_random_signal) | |
810 | /* We can stop during an inferior call because a signal is | |
811 | received. */ | |
812 | rc = 1; | |
813 | else if (!stop_stack_dummy) | |
814 | /* We may also stop prematurely because we hit a breakpoint in | |
815 | the called routine. */ | |
816 | rc = 2; | |
817 | else | |
818 | { | |
819 | /* On normal return, the stack dummy has been popped | |
820 | already. */ | |
821 | regcache_cpy_no_passthrough (buffer, stop_registers); | |
822 | rc = 0; | |
823 | } | |
824 | } | |
825 | ||
826 | if (rc == 1) | |
827 | { | |
828 | /* We stopped inside the FUNCTION because of a random signal. | |
829 | Further execution of the FUNCTION is not allowed. */ | |
830 | ||
831 | if (unwind_on_signal_p) | |
832 | { | |
833 | /* The user wants the context restored. */ | |
834 | ||
835 | /* We must get back to the frame we were before the dummy | |
836 | call. */ | |
837 | frame_pop (get_current_frame ()); | |
838 | ||
839 | /* FIXME: Insert a bunch of wrap_here; name can be very long if it's | |
840 | a C++ name with arguments and stuff. */ | |
841 | error ("\ | |
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.", | |
846 | name); | |
847 | } | |
848 | else | |
849 | { | |
850 | /* The user wants to stay in the frame where we stopped (default).*/ | |
851 | ||
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); | |
859 | ||
860 | /* FIXME: Insert a bunch of wrap_here; name can be very long if it's | |
861 | a C++ name with arguments and stuff. */ | |
862 | error ("\ | |
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.", | |
867 | name); | |
868 | } | |
869 | } | |
870 | ||
871 | if (rc == 2) | |
872 | { | |
873 | /* We hit a breakpoint inside the FUNCTION. */ | |
874 | ||
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 | |
879 | things. */ | |
880 | discard_cleanups (inf_status_cleanup); | |
881 | discard_inferior_status (inf_status); | |
882 | ||
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). */ | |
889 | ||
890 | /* FIXME: Insert a bunch of wrap_here; name can be very long if it's | |
891 | a C++ name with arguments and stuff. */ | |
892 | error ("\ | |
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); | |
897 | } | |
898 | ||
899 | /* If we get here the called FUNCTION run to completion. */ | |
900 | ||
901 | /* Restore the inferior status, via its cleanup. At this stage, | |
902 | leave the RETBUF alone. */ | |
903 | do_cleanups (inf_status_cleanup); | |
904 | ||
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 | |
914 | if (struct_return) | |
915 | { | |
916 | do_cleanups (retbuf_cleanup); | |
917 | return VALUE_RETURNED_FROM_STACK (value_type, struct_addr); | |
918 | } | |
919 | #endif | |
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)) | |
928 | { | |
929 | struct value *retval = value_at (value_type, struct_addr, NULL); | |
930 | do_cleanups (retbuf_cleanup); | |
931 | return retval; | |
932 | } | |
933 | else | |
934 | { | |
935 | struct value *retval = value_being_returned (value_type, retbuf, | |
936 | struct_return); | |
937 | do_cleanups (retbuf_cleanup); | |
938 | return retval; | |
939 | } | |
940 | } | |
941 | } | |
942 | ||
943 | void _initialize_infcall (void); | |
944 | ||
945 | void | |
946 | _initialize_infcall (void) | |
947 | { | |
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\ | |
956 | unprototyped.\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\ | |
964 | unprototyped.\n\ | |
965 | The default is to perform the conversion.\n", | |
966 | NULL, NULL, &setlist, &showlist); | |
967 | ||
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); | |
981 | } |