Commit | Line | Data |
---|---|---|
04714b91 AC |
1 | /* Perform an inferior function call, for GDB, the GNU debugger. |
2 | ||
6aba47ca DJ |
3 | Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, |
4 | 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 | |
9ab9195f | 5 | Free Software Foundation, Inc. |
04714b91 AC |
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 | |
197e01b6 EZ |
21 | Foundation, Inc., 51 Franklin Street, Fifth Floor, |
22 | Boston, MA 02110-1301, USA. */ | |
04714b91 AC |
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" | |
9ab9195f | 33 | #include "objfiles.h" |
04714b91 AC |
34 | #include "gdbcmd.h" |
35 | #include "command.h" | |
36 | #include "gdb_string.h" | |
b9362cc7 | 37 | #include "infcall.h" |
96860204 | 38 | #include "dummy-frame.h" |
04714b91 AC |
39 | |
40 | /* NOTE: cagney/2003-04-16: What's the future of this code? | |
41 | ||
42 | GDB needs an asynchronous expression evaluator, that means an | |
43 | asynchronous inferior function call implementation, and that in | |
44 | turn means restructuring the code so that it is event driven. */ | |
45 | ||
46 | /* How you should pass arguments to a function depends on whether it | |
47 | was defined in K&R style or prototype style. If you define a | |
48 | function using the K&R syntax that takes a `float' argument, then | |
49 | callers must pass that argument as a `double'. If you define the | |
50 | function using the prototype syntax, then you must pass the | |
51 | argument as a `float', with no promotion. | |
52 | ||
53 | Unfortunately, on certain older platforms, the debug info doesn't | |
54 | indicate reliably how each function was defined. A function type's | |
55 | TYPE_FLAG_PROTOTYPED flag may be clear, even if the function was | |
56 | defined in prototype style. When calling a function whose | |
57 | TYPE_FLAG_PROTOTYPED flag is clear, GDB consults this flag to | |
58 | decide what to do. | |
59 | ||
60 | For modern targets, it is proper to assume that, if the prototype | |
61 | flag is clear, that can be trusted: `float' arguments should be | |
62 | promoted to `double'. For some older targets, if the prototype | |
63 | flag is clear, that doesn't tell us anything. The default is to | |
64 | trust the debug information; the user can override this behavior | |
65 | with "set coerce-float-to-double 0". */ | |
66 | ||
67 | static int coerce_float_to_double_p = 1; | |
920d2a44 AC |
68 | static void |
69 | show_coerce_float_to_double_p (struct ui_file *file, int from_tty, | |
70 | struct cmd_list_element *c, const char *value) | |
71 | { | |
72 | fprintf_filtered (file, _("\ | |
73 | Coercion of floats to doubles when calling functions is %s.\n"), | |
74 | value); | |
75 | } | |
04714b91 AC |
76 | |
77 | /* This boolean tells what gdb should do if a signal is received while | |
78 | in a function called from gdb (call dummy). If set, gdb unwinds | |
79 | the stack and restore the context to what as it was before the | |
80 | call. | |
81 | ||
82 | The default is to stop in the frame where the signal was received. */ | |
83 | ||
84 | int unwind_on_signal_p = 0; | |
920d2a44 AC |
85 | static void |
86 | show_unwind_on_signal_p (struct ui_file *file, int from_tty, | |
87 | struct cmd_list_element *c, const char *value) | |
88 | { | |
89 | fprintf_filtered (file, _("\ | |
90 | Unwinding of stack if a signal is received while in a call dummy is %s.\n"), | |
91 | value); | |
92 | } | |
93 | ||
04714b91 AC |
94 | |
95 | /* Perform the standard coercions that are specified | |
96 | for arguments to be passed to C functions. | |
97 | ||
98 | If PARAM_TYPE is non-NULL, it is the expected parameter type. | |
99 | IS_PROTOTYPED is non-zero if the function declaration is prototyped. */ | |
100 | ||
101 | static struct value * | |
102 | value_arg_coerce (struct value *arg, struct type *param_type, | |
103 | int is_prototyped) | |
104 | { | |
df407dfe | 105 | struct type *arg_type = check_typedef (value_type (arg)); |
52f0bd74 | 106 | struct type *type |
04714b91 AC |
107 | = param_type ? check_typedef (param_type) : arg_type; |
108 | ||
109 | switch (TYPE_CODE (type)) | |
110 | { | |
111 | case TYPE_CODE_REF: | |
fb933624 DJ |
112 | { |
113 | struct value *new_value; | |
114 | ||
115 | if (TYPE_CODE (arg_type) == TYPE_CODE_REF) | |
116 | return value_cast_pointers (type, arg); | |
117 | ||
118 | /* Cast the value to the reference's target type, and then | |
119 | convert it back to a reference. This will issue an error | |
120 | if the value was not previously in memory - in some cases | |
121 | we should clearly be allowing this, but how? */ | |
122 | new_value = value_cast (TYPE_TARGET_TYPE (type), arg); | |
123 | new_value = value_ref (new_value); | |
124 | return new_value; | |
125 | } | |
04714b91 AC |
126 | case TYPE_CODE_INT: |
127 | case TYPE_CODE_CHAR: | |
128 | case TYPE_CODE_BOOL: | |
129 | case TYPE_CODE_ENUM: | |
130 | /* If we don't have a prototype, coerce to integer type if necessary. */ | |
131 | if (!is_prototyped) | |
132 | { | |
133 | if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int)) | |
134 | type = builtin_type_int; | |
135 | } | |
136 | /* Currently all target ABIs require at least the width of an integer | |
137 | type for an argument. We may have to conditionalize the following | |
138 | type coercion for future targets. */ | |
139 | if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int)) | |
140 | type = builtin_type_int; | |
141 | break; | |
142 | case TYPE_CODE_FLT: | |
143 | if (!is_prototyped && coerce_float_to_double_p) | |
144 | { | |
145 | if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_double)) | |
146 | type = builtin_type_double; | |
147 | else if (TYPE_LENGTH (type) > TYPE_LENGTH (builtin_type_double)) | |
148 | type = builtin_type_long_double; | |
149 | } | |
150 | break; | |
151 | case TYPE_CODE_FUNC: | |
152 | type = lookup_pointer_type (type); | |
153 | break; | |
154 | case TYPE_CODE_ARRAY: | |
155 | /* Arrays are coerced to pointers to their first element, unless | |
156 | they are vectors, in which case we want to leave them alone, | |
157 | because they are passed by value. */ | |
158 | if (current_language->c_style_arrays) | |
159 | if (!TYPE_VECTOR (type)) | |
160 | type = lookup_pointer_type (TYPE_TARGET_TYPE (type)); | |
161 | break; | |
162 | case TYPE_CODE_UNDEF: | |
163 | case TYPE_CODE_PTR: | |
164 | case TYPE_CODE_STRUCT: | |
165 | case TYPE_CODE_UNION: | |
166 | case TYPE_CODE_VOID: | |
167 | case TYPE_CODE_SET: | |
168 | case TYPE_CODE_RANGE: | |
169 | case TYPE_CODE_STRING: | |
170 | case TYPE_CODE_BITSTRING: | |
171 | case TYPE_CODE_ERROR: | |
0d5de010 DJ |
172 | case TYPE_CODE_MEMBERPTR: |
173 | case TYPE_CODE_METHODPTR: | |
04714b91 AC |
174 | case TYPE_CODE_METHOD: |
175 | case TYPE_CODE_COMPLEX: | |
176 | default: | |
177 | break; | |
178 | } | |
179 | ||
180 | return value_cast (type, arg); | |
181 | } | |
182 | ||
183 | /* Determine a function's address and its return type from its value. | |
184 | Calls error() if the function is not valid for calling. */ | |
185 | ||
a9fa03de | 186 | CORE_ADDR |
04714b91 AC |
187 | find_function_addr (struct value *function, struct type **retval_type) |
188 | { | |
df407dfe | 189 | struct type *ftype = check_typedef (value_type (function)); |
52f0bd74 | 190 | enum type_code code = TYPE_CODE (ftype); |
04714b91 AC |
191 | struct type *value_type; |
192 | CORE_ADDR funaddr; | |
193 | ||
194 | /* If it's a member function, just look at the function | |
195 | part of it. */ | |
196 | ||
197 | /* Determine address to call. */ | |
198 | if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD) | |
199 | { | |
200 | funaddr = VALUE_ADDRESS (function); | |
201 | value_type = TYPE_TARGET_TYPE (ftype); | |
202 | } | |
203 | else if (code == TYPE_CODE_PTR) | |
204 | { | |
205 | funaddr = value_as_address (function); | |
206 | ftype = check_typedef (TYPE_TARGET_TYPE (ftype)); | |
207 | if (TYPE_CODE (ftype) == TYPE_CODE_FUNC | |
208 | || TYPE_CODE (ftype) == TYPE_CODE_METHOD) | |
209 | { | |
e2d0e7eb AC |
210 | funaddr = gdbarch_convert_from_func_ptr_addr (current_gdbarch, |
211 | funaddr, | |
212 | ¤t_target); | |
04714b91 AC |
213 | value_type = TYPE_TARGET_TYPE (ftype); |
214 | } | |
215 | else | |
216 | value_type = builtin_type_int; | |
217 | } | |
218 | else if (code == TYPE_CODE_INT) | |
219 | { | |
220 | /* Handle the case of functions lacking debugging info. | |
221 | Their values are characters since their addresses are char */ | |
222 | if (TYPE_LENGTH (ftype) == 1) | |
223 | funaddr = value_as_address (value_addr (function)); | |
224 | else | |
225 | /* Handle integer used as address of a function. */ | |
226 | funaddr = (CORE_ADDR) value_as_long (function); | |
227 | ||
228 | value_type = builtin_type_int; | |
229 | } | |
230 | else | |
8a3fe4f8 | 231 | error (_("Invalid data type for function to be called.")); |
04714b91 | 232 | |
7d9b040b RC |
233 | if (retval_type != NULL) |
234 | *retval_type = value_type; | |
782263ab | 235 | return funaddr + DEPRECATED_FUNCTION_START_OFFSET; |
04714b91 AC |
236 | } |
237 | ||
238 | /* Call breakpoint_auto_delete on the current contents of the bpstat | |
239 | pointed to by arg (which is really a bpstat *). */ | |
240 | ||
241 | static void | |
242 | breakpoint_auto_delete_contents (void *arg) | |
243 | { | |
244 | breakpoint_auto_delete (*(bpstat *) arg); | |
245 | } | |
246 | ||
7043d8dc AC |
247 | static CORE_ADDR |
248 | generic_push_dummy_code (struct gdbarch *gdbarch, | |
249 | CORE_ADDR sp, CORE_ADDR funaddr, int using_gcc, | |
250 | struct value **args, int nargs, | |
251 | struct type *value_type, | |
e4fd649a UW |
252 | CORE_ADDR *real_pc, CORE_ADDR *bp_addr, |
253 | struct regcache *regcache) | |
7043d8dc AC |
254 | { |
255 | /* Something here to findout the size of a breakpoint and then | |
256 | allocate space for it on the stack. */ | |
257 | int bplen; | |
258 | /* This code assumes frame align. */ | |
259 | gdb_assert (gdbarch_frame_align_p (gdbarch)); | |
260 | /* Force the stack's alignment. The intent is to ensure that the SP | |
261 | is aligned to at least a breakpoint instruction's boundary. */ | |
262 | sp = gdbarch_frame_align (gdbarch, sp); | |
263 | /* Allocate space for, and then position the breakpoint on the | |
264 | stack. */ | |
265 | if (gdbarch_inner_than (gdbarch, 1, 2)) | |
266 | { | |
267 | CORE_ADDR bppc = sp; | |
268 | gdbarch_breakpoint_from_pc (gdbarch, &bppc, &bplen); | |
269 | sp = gdbarch_frame_align (gdbarch, sp - bplen); | |
270 | (*bp_addr) = sp; | |
271 | /* Should the breakpoint size/location be re-computed here? */ | |
272 | } | |
273 | else | |
274 | { | |
275 | (*bp_addr) = sp; | |
276 | gdbarch_breakpoint_from_pc (gdbarch, bp_addr, &bplen); | |
277 | sp = gdbarch_frame_align (gdbarch, sp + bplen); | |
278 | } | |
279 | /* Inferior resumes at the function entry point. */ | |
280 | (*real_pc) = funaddr; | |
281 | return sp; | |
282 | } | |
283 | ||
d3712828 AC |
284 | /* For CALL_DUMMY_ON_STACK, push a breakpoint sequence that the called |
285 | function returns to. */ | |
7043d8dc AC |
286 | |
287 | static CORE_ADDR | |
288 | push_dummy_code (struct gdbarch *gdbarch, | |
289 | CORE_ADDR sp, CORE_ADDR funaddr, int using_gcc, | |
290 | struct value **args, int nargs, | |
291 | struct type *value_type, | |
e4fd649a UW |
292 | CORE_ADDR *real_pc, CORE_ADDR *bp_addr, |
293 | struct regcache *regcache) | |
7043d8dc AC |
294 | { |
295 | if (gdbarch_push_dummy_code_p (gdbarch)) | |
296 | return gdbarch_push_dummy_code (gdbarch, sp, funaddr, using_gcc, | |
e4fd649a UW |
297 | args, nargs, value_type, real_pc, bp_addr, |
298 | regcache); | |
7043d8dc AC |
299 | else |
300 | return generic_push_dummy_code (gdbarch, sp, funaddr, using_gcc, | |
e4fd649a UW |
301 | args, nargs, value_type, real_pc, bp_addr, |
302 | regcache); | |
7043d8dc AC |
303 | } |
304 | ||
04714b91 AC |
305 | /* All this stuff with a dummy frame may seem unnecessarily complicated |
306 | (why not just save registers in GDB?). The purpose of pushing a dummy | |
307 | frame which looks just like a real frame is so that if you call a | |
308 | function and then hit a breakpoint (get a signal, etc), "backtrace" | |
309 | will look right. Whether the backtrace needs to actually show the | |
310 | stack at the time the inferior function was called is debatable, but | |
311 | it certainly needs to not display garbage. So if you are contemplating | |
312 | making dummy frames be different from normal frames, consider that. */ | |
313 | ||
314 | /* Perform a function call in the inferior. | |
315 | ARGS is a vector of values of arguments (NARGS of them). | |
316 | FUNCTION is a value, the function to be called. | |
317 | Returns a value representing what the function returned. | |
318 | May fail to return, if a breakpoint or signal is hit | |
319 | during the execution of the function. | |
320 | ||
321 | ARGS is modified to contain coerced values. */ | |
322 | ||
323 | struct value * | |
324 | call_function_by_hand (struct value *function, int nargs, struct value **args) | |
325 | { | |
52f0bd74 | 326 | CORE_ADDR sp; |
04714b91 | 327 | CORE_ADDR dummy_addr; |
df407dfe | 328 | struct type *values_type; |
04714b91 AC |
329 | unsigned char struct_return; |
330 | CORE_ADDR struct_addr = 0; | |
331 | struct regcache *retbuf; | |
332 | struct cleanup *retbuf_cleanup; | |
333 | struct inferior_status *inf_status; | |
334 | struct cleanup *inf_status_cleanup; | |
335 | CORE_ADDR funaddr; | |
336 | int using_gcc; /* Set to version of gcc in use, or zero if not gcc */ | |
337 | CORE_ADDR real_pc; | |
df407dfe | 338 | struct type *ftype = check_typedef (value_type (function)); |
d585e13a | 339 | CORE_ADDR bp_addr; |
96860204 AC |
340 | struct regcache *caller_regcache; |
341 | struct cleanup *caller_regcache_cleanup; | |
342 | struct frame_id dummy_id; | |
04714b91 | 343 | |
4c850810 DJ |
344 | if (TYPE_CODE (ftype) == TYPE_CODE_PTR) |
345 | ftype = check_typedef (TYPE_TARGET_TYPE (ftype)); | |
346 | ||
04714b91 AC |
347 | if (!target_has_execution) |
348 | noprocess (); | |
349 | ||
a86c5fc9 MK |
350 | if (!gdbarch_push_dummy_call_p (current_gdbarch)) |
351 | error (_("This target does not support function calls")); | |
352 | ||
04714b91 AC |
353 | /* Create a cleanup chain that contains the retbuf (buffer |
354 | containing the register values). This chain is create BEFORE the | |
355 | inf_status chain so that the inferior status can cleaned up | |
356 | (restored or discarded) without having the retbuf freed. */ | |
357 | retbuf = regcache_xmalloc (current_gdbarch); | |
358 | retbuf_cleanup = make_cleanup_regcache_xfree (retbuf); | |
359 | ||
360 | /* A cleanup for the inferior status. Create this AFTER the retbuf | |
361 | so that this can be discarded or applied without interfering with | |
362 | the regbuf. */ | |
363 | inf_status = save_inferior_status (1); | |
364 | inf_status_cleanup = make_cleanup_restore_inferior_status (inf_status); | |
365 | ||
96860204 AC |
366 | /* Save the caller's registers so that they can be restored once the |
367 | callee returns. To allow nested calls the registers are (further | |
368 | down) pushed onto a dummy frame stack. Include a cleanup (which | |
369 | is tossed once the regcache has been pushed). */ | |
370 | caller_regcache = frame_save_as_regcache (get_current_frame ()); | |
371 | caller_regcache_cleanup = make_cleanup_regcache_xfree (caller_regcache); | |
04714b91 | 372 | |
04714b91 | 373 | /* Ensure that the initial SP is correctly aligned. */ |
ebc7896c | 374 | { |
fb4443d8 | 375 | CORE_ADDR old_sp = get_frame_sp (get_current_frame ()); |
ebc7896c AC |
376 | if (gdbarch_frame_align_p (current_gdbarch)) |
377 | { | |
8b148df9 AC |
378 | sp = gdbarch_frame_align (current_gdbarch, old_sp); |
379 | /* NOTE: cagney/2003-08-13: Skip the "red zone". For some | |
380 | ABIs, a function can use memory beyond the inner most stack | |
381 | address. AMD64 called that region the "red zone". Skip at | |
382 | least the "red zone" size before allocating any space on | |
383 | the stack. */ | |
4d1e7dd1 | 384 | if (gdbarch_inner_than (current_gdbarch, 1, 2)) |
8b148df9 AC |
385 | sp -= gdbarch_frame_red_zone_size (current_gdbarch); |
386 | else | |
387 | sp += gdbarch_frame_red_zone_size (current_gdbarch); | |
388 | /* Still aligned? */ | |
389 | gdb_assert (sp == gdbarch_frame_align (current_gdbarch, sp)); | |
ebc7896c AC |
390 | /* NOTE: cagney/2002-09-18: |
391 | ||
392 | On a RISC architecture, a void parameterless generic dummy | |
393 | frame (i.e., no parameters, no result) typically does not | |
394 | need to push anything the stack and hence can leave SP and | |
c48a845b | 395 | FP. Similarly, a frameless (possibly leaf) function does |
ebc7896c AC |
396 | not push anything on the stack and, hence, that too can |
397 | leave FP and SP unchanged. As a consequence, a sequence of | |
398 | void parameterless generic dummy frame calls to frameless | |
399 | functions will create a sequence of effectively identical | |
400 | frames (SP, FP and TOS and PC the same). This, not | |
401 | suprisingly, results in what appears to be a stack in an | |
402 | infinite loop --- when GDB tries to find a generic dummy | |
403 | frame on the internal dummy frame stack, it will always | |
404 | find the first one. | |
405 | ||
406 | To avoid this problem, the code below always grows the | |
407 | stack. That way, two dummy frames can never be identical. | |
408 | It does burn a few bytes of stack but that is a small price | |
409 | to pay :-). */ | |
ebc7896c AC |
410 | if (sp == old_sp) |
411 | { | |
4d1e7dd1 | 412 | if (gdbarch_inner_than (current_gdbarch, 1, 2)) |
ebc7896c AC |
413 | /* Stack grows down. */ |
414 | sp = gdbarch_frame_align (current_gdbarch, old_sp - 1); | |
415 | else | |
416 | /* Stack grows up. */ | |
417 | sp = gdbarch_frame_align (current_gdbarch, old_sp + 1); | |
418 | } | |
4d1e7dd1 UW |
419 | gdb_assert ((gdbarch_inner_than (current_gdbarch, 1, 2) |
420 | && sp <= old_sp) | |
421 | || (gdbarch_inner_than (current_gdbarch, 2, 1) | |
422 | && sp >= old_sp)); | |
ebc7896c AC |
423 | } |
424 | else | |
a59fe496 AC |
425 | /* FIXME: cagney/2002-09-18: Hey, you loose! |
426 | ||
8b148df9 AC |
427 | Who knows how badly aligned the SP is! |
428 | ||
429 | If the generic dummy frame ends up empty (because nothing is | |
430 | pushed) GDB won't be able to correctly perform back traces. | |
431 | If a target is having trouble with backtraces, first thing to | |
432 | do is add FRAME_ALIGN() to the architecture vector. If that | |
433 | fails, try unwind_dummy_id(). | |
434 | ||
435 | If the ABI specifies a "Red Zone" (see the doco) the code | |
436 | below will quietly trash it. */ | |
ebc7896c AC |
437 | sp = old_sp; |
438 | } | |
04714b91 | 439 | |
df407dfe AC |
440 | funaddr = find_function_addr (function, &values_type); |
441 | CHECK_TYPEDEF (values_type); | |
04714b91 AC |
442 | |
443 | { | |
444 | struct block *b = block_for_pc (funaddr); | |
445 | /* If compiled without -g, assume GCC 2. */ | |
446 | using_gcc = (b == NULL ? 2 : BLOCK_GCC_COMPILED (b)); | |
447 | } | |
448 | ||
449 | /* Are we returning a value using a structure return or a normal | |
450 | value return? */ | |
451 | ||
df407dfe | 452 | struct_return = using_struct_return (values_type, using_gcc); |
04714b91 | 453 | |
7043d8dc AC |
454 | /* Determine the location of the breakpoint (and possibly other |
455 | stuff) that the called function will return to. The SPARC, for a | |
456 | function returning a structure or union, needs to make space for | |
457 | not just the breakpoint but also an extra word containing the | |
458 | size (?) of the structure being passed. */ | |
459 | ||
460 | /* The actual breakpoint (at BP_ADDR) is inserted separatly so there | |
461 | is no need to write that out. */ | |
462 | ||
faaf634c | 463 | switch (gdbarch_call_dummy_location (current_gdbarch)) |
04714b91 AC |
464 | { |
465 | case ON_STACK: | |
7043d8dc AC |
466 | /* "dummy_addr" is here just to keep old targets happy. New |
467 | targets return that same information via "sp" and "bp_addr". */ | |
4d1e7dd1 | 468 | if (gdbarch_inner_than (current_gdbarch, 1, 2)) |
d585e13a | 469 | { |
7043d8dc | 470 | sp = push_dummy_code (current_gdbarch, sp, funaddr, |
df407dfe | 471 | using_gcc, args, nargs, values_type, |
594f7785 | 472 | &real_pc, &bp_addr, get_current_regcache ()); |
7043d8dc | 473 | dummy_addr = sp; |
d585e13a | 474 | } |
7043d8dc AC |
475 | else |
476 | { | |
477 | dummy_addr = sp; | |
478 | sp = push_dummy_code (current_gdbarch, sp, funaddr, | |
df407dfe | 479 | using_gcc, args, nargs, values_type, |
594f7785 | 480 | &real_pc, &bp_addr, get_current_regcache ()); |
7043d8dc AC |
481 | } |
482 | break; | |
04714b91 AC |
483 | case AT_ENTRY_POINT: |
484 | real_pc = funaddr; | |
88a82a65 | 485 | dummy_addr = entry_point_address (); |
0285512f AC |
486 | /* Make certain that the address points at real code, and not a |
487 | function descriptor. */ | |
e2d0e7eb AC |
488 | dummy_addr = gdbarch_convert_from_func_ptr_addr (current_gdbarch, |
489 | dummy_addr, | |
490 | ¤t_target); | |
d585e13a AC |
491 | /* A call dummy always consists of just a single breakpoint, so |
492 | it's address is the same as the address of the dummy. */ | |
493 | bp_addr = dummy_addr; | |
04714b91 | 494 | break; |
9710e734 AC |
495 | case AT_SYMBOL: |
496 | /* Some executables define a symbol __CALL_DUMMY_ADDRESS whose | |
497 | address is the location where the breakpoint should be | |
498 | placed. Once all targets are using the overhauled frame code | |
499 | this can be deleted - ON_STACK is a better option. */ | |
500 | { | |
501 | struct minimal_symbol *sym; | |
502 | ||
503 | sym = lookup_minimal_symbol ("__CALL_DUMMY_ADDRESS", NULL, NULL); | |
504 | real_pc = funaddr; | |
505 | if (sym) | |
506 | dummy_addr = SYMBOL_VALUE_ADDRESS (sym); | |
507 | else | |
508 | dummy_addr = entry_point_address (); | |
0285512f AC |
509 | /* Make certain that the address points at real code, and not |
510 | a function descriptor. */ | |
e2d0e7eb AC |
511 | dummy_addr = gdbarch_convert_from_func_ptr_addr (current_gdbarch, |
512 | dummy_addr, | |
513 | ¤t_target); | |
0285512f AC |
514 | /* A call dummy always consists of just a single breakpoint, |
515 | so it's address is the same as the address of the dummy. */ | |
9710e734 AC |
516 | bp_addr = dummy_addr; |
517 | break; | |
518 | } | |
04714b91 | 519 | default: |
e2e0b3e5 | 520 | internal_error (__FILE__, __LINE__, _("bad switch")); |
04714b91 AC |
521 | } |
522 | ||
04714b91 | 523 | if (nargs < TYPE_NFIELDS (ftype)) |
8a3fe4f8 | 524 | error (_("too few arguments in function call")); |
04714b91 | 525 | |
ebc7896c AC |
526 | { |
527 | int i; | |
528 | for (i = nargs - 1; i >= 0; i--) | |
529 | { | |
530 | int prototyped; | |
531 | struct type *param_type; | |
532 | ||
533 | /* FIXME drow/2002-05-31: Should just always mark methods as | |
534 | prototyped. Can we respect TYPE_VARARGS? Probably not. */ | |
535 | if (TYPE_CODE (ftype) == TYPE_CODE_METHOD) | |
536 | prototyped = 1; | |
537 | else if (i < TYPE_NFIELDS (ftype)) | |
538 | prototyped = TYPE_PROTOTYPED (ftype); | |
539 | else | |
540 | prototyped = 0; | |
541 | ||
542 | if (i < TYPE_NFIELDS (ftype)) | |
543 | param_type = TYPE_FIELD_TYPE (ftype, i); | |
544 | else | |
545 | param_type = NULL; | |
546 | ||
547 | args[i] = value_arg_coerce (args[i], param_type, prototyped); | |
548 | ||
549 | /* elz: this code is to handle the case in which the function | |
550 | to be called has a pointer to function as parameter and the | |
551 | corresponding actual argument is the address of a function | |
552 | and not a pointer to function variable. In aCC compiled | |
553 | code, the calls through pointers to functions (in the body | |
554 | of the function called by hand) are made via | |
555 | $$dyncall_external which requires some registers setting, | |
556 | this is taken care of if we call via a function pointer | |
557 | variable, but not via a function address. In cc this is | |
558 | not a problem. */ | |
559 | ||
560 | if (using_gcc == 0) | |
561 | { | |
562 | if (param_type != NULL && TYPE_CODE (ftype) != TYPE_CODE_METHOD) | |
563 | { | |
564 | /* if this parameter is a pointer to function. */ | |
565 | if (TYPE_CODE (param_type) == TYPE_CODE_PTR) | |
566 | if (TYPE_CODE (TYPE_TARGET_TYPE (param_type)) == TYPE_CODE_FUNC) | |
567 | /* elz: FIXME here should go the test about the | |
568 | compiler used to compile the target. We want to | |
569 | issue the error message only if the compiler | |
570 | used was HP's aCC. If we used HP's cc, then | |
571 | there is no problem and no need to return at | |
572 | this point. */ | |
573 | /* Go see if the actual parameter is a variable of | |
574 | type pointer to function or just a function. */ | |
5086187c | 575 | if (VALUE_LVAL (args[i]) == not_lval) |
ebc7896c AC |
576 | { |
577 | char *arg_name; | |
5086187c AC |
578 | /* NOTE: cagney/2005-01-02: THIS IS BOGUS. */ |
579 | if (find_pc_partial_function ((CORE_ADDR) value_contents (args[i])[0], &arg_name, NULL, NULL)) | |
8a3fe4f8 | 580 | error (_("\ |
04714b91 | 581 | You cannot use function <%s> as argument. \n\ |
8a3fe4f8 | 582 | You must use a pointer to function type variable. Command ignored."), arg_name); |
ebc7896c AC |
583 | } |
584 | } | |
585 | } | |
586 | } | |
587 | } | |
04714b91 | 588 | |
8e823e25 | 589 | if (DEPRECATED_REG_STRUCT_HAS_ADDR_P ()) |
04714b91 | 590 | { |
ebc7896c | 591 | int i; |
04714b91 AC |
592 | /* This is a machine like the sparc, where we may need to pass a |
593 | pointer to the structure, not the structure itself. */ | |
594 | for (i = nargs - 1; i >= 0; i--) | |
595 | { | |
df407dfe | 596 | struct type *arg_type = check_typedef (value_type (args[i])); |
04714b91 AC |
597 | if ((TYPE_CODE (arg_type) == TYPE_CODE_STRUCT |
598 | || TYPE_CODE (arg_type) == TYPE_CODE_UNION | |
599 | || TYPE_CODE (arg_type) == TYPE_CODE_ARRAY | |
600 | || TYPE_CODE (arg_type) == TYPE_CODE_STRING | |
601 | || TYPE_CODE (arg_type) == TYPE_CODE_BITSTRING | |
602 | || TYPE_CODE (arg_type) == TYPE_CODE_SET | |
603 | || (TYPE_CODE (arg_type) == TYPE_CODE_FLT | |
604 | && TYPE_LENGTH (arg_type) > 8) | |
605 | ) | |
8e823e25 | 606 | && DEPRECATED_REG_STRUCT_HAS_ADDR (using_gcc, arg_type)) |
04714b91 AC |
607 | { |
608 | CORE_ADDR addr; | |
609 | int len; /* = TYPE_LENGTH (arg_type); */ | |
610 | int aligned_len; | |
4754a64e | 611 | arg_type = check_typedef (value_enclosing_type (args[i])); |
04714b91 AC |
612 | len = TYPE_LENGTH (arg_type); |
613 | ||
8241eaa6 | 614 | aligned_len = len; |
4d1e7dd1 | 615 | if (gdbarch_inner_than (current_gdbarch, 1, 2)) |
04714b91 AC |
616 | { |
617 | /* stack grows downward */ | |
618 | sp -= aligned_len; | |
619 | /* ... so the address of the thing we push is the | |
620 | stack pointer after we push it. */ | |
621 | addr = sp; | |
622 | } | |
623 | else | |
624 | { | |
625 | /* The stack grows up, so the address of the thing | |
626 | we push is the stack pointer before we push it. */ | |
627 | addr = sp; | |
628 | sp += aligned_len; | |
629 | } | |
630 | /* Push the structure. */ | |
46615f07 | 631 | write_memory (addr, value_contents_all (args[i]), len); |
04714b91 AC |
632 | /* The value we're going to pass is the address of the |
633 | thing we just pushed. */ | |
df407dfe | 634 | /*args[i] = value_from_longest (lookup_pointer_type (values_type), |
04714b91 AC |
635 | (LONGEST) addr); */ |
636 | args[i] = value_from_pointer (lookup_pointer_type (arg_type), | |
637 | addr); | |
638 | } | |
639 | } | |
640 | } | |
641 | ||
642 | ||
643 | /* Reserve space for the return structure to be written on the | |
644 | stack, if necessary. Make certain that the value is correctly | |
645 | aligned. */ | |
646 | ||
647 | if (struct_return) | |
648 | { | |
df407dfe | 649 | int len = TYPE_LENGTH (values_type); |
4d1e7dd1 | 650 | if (gdbarch_inner_than (current_gdbarch, 1, 2)) |
04714b91 AC |
651 | { |
652 | /* Stack grows downward. Align STRUCT_ADDR and SP after | |
653 | making space for the return value. */ | |
654 | sp -= len; | |
655 | if (gdbarch_frame_align_p (current_gdbarch)) | |
656 | sp = gdbarch_frame_align (current_gdbarch, sp); | |
657 | struct_addr = sp; | |
658 | } | |
659 | else | |
660 | { | |
661 | /* Stack grows upward. Align the frame, allocate space, and | |
662 | then again, re-align the frame??? */ | |
663 | if (gdbarch_frame_align_p (current_gdbarch)) | |
664 | sp = gdbarch_frame_align (current_gdbarch, sp); | |
665 | struct_addr = sp; | |
666 | sp += len; | |
667 | if (gdbarch_frame_align_p (current_gdbarch)) | |
668 | sp = gdbarch_frame_align (current_gdbarch, sp); | |
669 | } | |
670 | } | |
671 | ||
04714b91 AC |
672 | /* Create the dummy stack frame. Pass in the call dummy address as, |
673 | presumably, the ABI code knows where, in the call dummy, the | |
674 | return address should be pointed. */ | |
594f7785 UW |
675 | sp = gdbarch_push_dummy_call (current_gdbarch, function, |
676 | get_current_regcache (), bp_addr, nargs, args, | |
677 | sp, struct_return, struct_addr); | |
04714b91 | 678 | |
96860204 AC |
679 | /* Set up a frame ID for the dummy frame so we can pass it to |
680 | set_momentary_breakpoint. We need to give the breakpoint a frame | |
681 | ID so that the breakpoint code can correctly re-identify the | |
682 | dummy breakpoint. */ | |
8241eaa6 AC |
683 | /* Sanity. The exact same SP value is returned by PUSH_DUMMY_CALL, |
684 | saved as the dummy-frame TOS, and used by unwind_dummy_id to form | |
685 | the frame ID's stack address. */ | |
96860204 | 686 | dummy_id = frame_id_build (sp, bp_addr); |
04714b91 | 687 | |
74cfe982 AC |
688 | /* Create a momentary breakpoint at the return address of the |
689 | inferior. That way it breaks when it returns. */ | |
04714b91 | 690 | |
74cfe982 AC |
691 | { |
692 | struct breakpoint *bpt; | |
693 | struct symtab_and_line sal; | |
74cfe982 AC |
694 | init_sal (&sal); /* initialize to zeroes */ |
695 | sal.pc = bp_addr; | |
696 | sal.section = find_pc_overlay (sal.pc); | |
8241eaa6 AC |
697 | /* Sanity. The exact same SP value is returned by |
698 | PUSH_DUMMY_CALL, saved as the dummy-frame TOS, and used by | |
699 | unwind_dummy_id to form the frame ID's stack address. */ | |
96860204 | 700 | bpt = set_momentary_breakpoint (sal, dummy_id, bp_call_dummy); |
74cfe982 AC |
701 | bpt->disposition = disp_del; |
702 | } | |
04714b91 | 703 | |
96860204 AC |
704 | /* Everything's ready, push all the info needed to restore the |
705 | caller (and identify the dummy-frame) onto the dummy-frame | |
706 | stack. */ | |
707 | dummy_frame_push (caller_regcache, &dummy_id); | |
708 | discard_cleanups (caller_regcache_cleanup); | |
709 | ||
710 | /* - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - | |
711 | If you're looking to implement asynchronous dummy-frames, then | |
712 | just below is the place to chop this function in two.. */ | |
713 | ||
714 | /* Now proceed, having reached the desired place. */ | |
715 | clear_proceed_status (); | |
716 | ||
74cfe982 AC |
717 | /* Execute a "stack dummy", a piece of code stored in the stack by |
718 | the debugger to be executed in the inferior. | |
04714b91 | 719 | |
74cfe982 AC |
720 | The dummy's frame is automatically popped whenever that break is |
721 | hit. If that is the first time the program stops, | |
722 | call_function_by_hand returns to its caller with that frame | |
723 | already gone and sets RC to 0. | |
724 | ||
725 | Otherwise, set RC to a non-zero value. If the called function | |
726 | receives a random signal, we do not allow the user to continue | |
727 | executing it as this may not work. The dummy frame is poped and | |
728 | we return 1. If we hit a breakpoint, we leave the frame in place | |
729 | and return 2 (the frame will eventually be popped when we do hit | |
730 | the dummy end breakpoint). */ | |
04714b91 | 731 | |
74cfe982 AC |
732 | { |
733 | struct cleanup *old_cleanups = make_cleanup (null_cleanup, 0); | |
734 | int saved_async = 0; | |
735 | ||
736 | /* If all error()s out of proceed ended up calling normal_stop | |
737 | (and perhaps they should; it already does in the special case | |
738 | of error out of resume()), then we wouldn't need this. */ | |
739 | make_cleanup (breakpoint_auto_delete_contents, &stop_bpstat); | |
740 | ||
741 | disable_watchpoints_before_interactive_call_start (); | |
742 | proceed_to_finish = 1; /* We want stop_registers, please... */ | |
743 | ||
744 | if (target_can_async_p ()) | |
745 | saved_async = target_async_mask (0); | |
746 | ||
747 | proceed (real_pc, TARGET_SIGNAL_0, 0); | |
748 | ||
749 | if (saved_async) | |
750 | target_async_mask (saved_async); | |
751 | ||
752 | enable_watchpoints_after_interactive_call_stop (); | |
04714b91 | 753 | |
74cfe982 | 754 | discard_cleanups (old_cleanups); |
52557533 | 755 | } |
04714b91 | 756 | |
52557533 AC |
757 | if (stopped_by_random_signal || !stop_stack_dummy) |
758 | { | |
759 | /* Find the name of the function we're about to complain about. */ | |
edcf254d | 760 | const char *name = NULL; |
04714b91 | 761 | { |
52557533 AC |
762 | struct symbol *symbol = find_pc_function (funaddr); |
763 | if (symbol) | |
764 | name = SYMBOL_PRINT_NAME (symbol); | |
765 | else | |
04714b91 | 766 | { |
52557533 AC |
767 | /* Try the minimal symbols. */ |
768 | struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (funaddr); | |
769 | if (msymbol) | |
770 | name = SYMBOL_PRINT_NAME (msymbol); | |
771 | } | |
edcf254d AC |
772 | if (name == NULL) |
773 | { | |
774 | /* Can't use a cleanup here. It is discarded, instead use | |
775 | an alloca. */ | |
bb599908 | 776 | char *tmp = xstrprintf ("at %s", hex_string (funaddr)); |
edcf254d AC |
777 | char *a = alloca (strlen (tmp) + 1); |
778 | strcpy (a, tmp); | |
779 | xfree (tmp); | |
780 | name = a; | |
781 | } | |
52557533 | 782 | } |
52557533 AC |
783 | if (stopped_by_random_signal) |
784 | { | |
785 | /* We stopped inside the FUNCTION because of a random | |
786 | signal. Further execution of the FUNCTION is not | |
787 | allowed. */ | |
04714b91 | 788 | |
52557533 AC |
789 | if (unwind_on_signal_p) |
790 | { | |
791 | /* The user wants the context restored. */ | |
792 | ||
793 | /* We must get back to the frame we were before the | |
794 | dummy call. */ | |
795 | frame_pop (get_current_frame ()); | |
04714b91 | 796 | |
52557533 AC |
797 | /* FIXME: Insert a bunch of wrap_here; name can be very |
798 | long if it's a C++ name with arguments and stuff. */ | |
8a3fe4f8 | 799 | error (_("\ |
04714b91 AC |
800 | The program being debugged was signaled while in a function called from GDB.\n\ |
801 | GDB has restored the context to what it was before the call.\n\ | |
802 | To change this behavior use \"set unwindonsignal off\"\n\ | |
8a3fe4f8 | 803 | Evaluation of the expression containing the function (%s) will be abandoned."), |
52557533 AC |
804 | name); |
805 | } | |
806 | else | |
807 | { | |
808 | /* The user wants to stay in the frame where we stopped | |
809 | (default).*/ | |
810 | /* If we restored the inferior status (via the cleanup), | |
811 | we would print a spurious error message (Unable to | |
812 | restore previously selected frame), would write the | |
813 | registers from the inf_status (which is wrong), and | |
814 | would do other wrong things. */ | |
815 | discard_cleanups (inf_status_cleanup); | |
816 | discard_inferior_status (inf_status); | |
817 | /* FIXME: Insert a bunch of wrap_here; name can be very | |
818 | long if it's a C++ name with arguments and stuff. */ | |
8a3fe4f8 | 819 | error (_("\ |
04714b91 AC |
820 | The program being debugged was signaled while in a function called from GDB.\n\ |
821 | GDB remains in the frame where the signal was received.\n\ | |
822 | To change this behavior use \"set unwindonsignal on\"\n\ | |
8a3fe4f8 | 823 | Evaluation of the expression containing the function (%s) will be abandoned."), |
52557533 AC |
824 | name); |
825 | } | |
826 | } | |
04714b91 | 827 | |
52557533 AC |
828 | if (!stop_stack_dummy) |
829 | { | |
830 | /* We hit a breakpoint inside the FUNCTION. */ | |
831 | /* If we restored the inferior status (via the cleanup), we | |
832 | would print a spurious error message (Unable to restore | |
833 | previously selected frame), would write the registers | |
834 | from the inf_status (which is wrong), and would do other | |
835 | wrong things. */ | |
836 | discard_cleanups (inf_status_cleanup); | |
837 | discard_inferior_status (inf_status); | |
838 | /* The following error message used to say "The expression | |
839 | which contained the function call has been discarded." | |
840 | It is a hard concept to explain in a few words. Ideally, | |
841 | GDB would be able to resume evaluation of the expression | |
842 | when the function finally is done executing. Perhaps | |
843 | someday this will be implemented (it would not be easy). */ | |
844 | /* FIXME: Insert a bunch of wrap_here; name can be very long if it's | |
845 | a C++ name with arguments and stuff. */ | |
8a3fe4f8 | 846 | error (_("\ |
04714b91 AC |
847 | The program being debugged stopped while in a function called from GDB.\n\ |
848 | When the function (%s) is done executing, GDB will silently\n\ | |
849 | stop (instead of continuing to evaluate the expression containing\n\ | |
8a3fe4f8 | 850 | the function call)."), name); |
52557533 AC |
851 | } |
852 | ||
853 | /* The above code errors out, so ... */ | |
e2e0b3e5 | 854 | internal_error (__FILE__, __LINE__, _("... should not be here")); |
52557533 | 855 | } |
04714b91 | 856 | |
74cfe982 AC |
857 | /* If we get here the called FUNCTION run to completion. */ |
858 | ||
859 | /* On normal return, the stack dummy has been popped already. */ | |
860 | regcache_cpy_no_passthrough (retbuf, stop_registers); | |
861 | ||
862 | /* Restore the inferior status, via its cleanup. At this stage, | |
863 | leave the RETBUF alone. */ | |
864 | do_cleanups (inf_status_cleanup); | |
865 | ||
1a4d7a36 | 866 | /* Figure out the value returned by the function. */ |
44e5158b | 867 | { |
1a4d7a36 MK |
868 | struct value *retval = NULL; |
869 | ||
df407dfe | 870 | if (TYPE_CODE (values_type) == TYPE_CODE_VOID) |
44e5158b | 871 | { |
1a4d7a36 MK |
872 | /* If the function returns void, don't bother fetching the |
873 | return value. */ | |
df407dfe | 874 | retval = allocate_value (values_type); |
44e5158b | 875 | } |
1a4d7a36 MK |
876 | else |
877 | { | |
878 | struct gdbarch *arch = current_gdbarch; | |
879 | ||
880 | switch (gdbarch_return_value (arch, values_type, NULL, NULL, NULL)) | |
881 | { | |
882 | case RETURN_VALUE_REGISTER_CONVENTION: | |
883 | case RETURN_VALUE_ABI_RETURNS_ADDRESS: | |
884 | case RETURN_VALUE_ABI_PRESERVES_ADDRESS: | |
885 | retval = allocate_value (values_type); | |
886 | gdbarch_return_value (current_gdbarch, values_type, retbuf, | |
887 | value_contents_raw (retval), NULL); | |
888 | break; | |
889 | case RETURN_VALUE_STRUCT_CONVENTION: | |
890 | retval = value_at (values_type, struct_addr); | |
891 | break; | |
892 | } | |
893 | } | |
894 | ||
44e5158b | 895 | do_cleanups (retbuf_cleanup); |
1a4d7a36 MK |
896 | |
897 | gdb_assert(retval); | |
44e5158b AC |
898 | return retval; |
899 | } | |
04714b91 | 900 | } |
1a4d7a36 | 901 | \f |
04714b91 | 902 | |
1a4d7a36 | 903 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
04714b91 AC |
904 | void _initialize_infcall (void); |
905 | ||
906 | void | |
907 | _initialize_infcall (void) | |
908 | { | |
909 | add_setshow_boolean_cmd ("coerce-float-to-double", class_obscure, | |
7915a72c AC |
910 | &coerce_float_to_double_p, _("\ |
911 | Set coercion of floats to doubles when calling functions."), _("\ | |
912 | Show coercion of floats to doubles when calling functions"), _("\ | |
04714b91 AC |
913 | Variables of type float should generally be converted to doubles before\n\ |
914 | calling an unprototyped function, and left alone when calling a prototyped\n\ | |
915 | function. However, some older debug info formats do not provide enough\n\ | |
916 | information to determine that a function is prototyped. If this flag is\n\ | |
917 | set, GDB will perform the conversion for a function it considers\n\ | |
918 | unprototyped.\n\ | |
7915a72c | 919 | The default is to perform the conversion.\n"), |
2c5b56ce | 920 | NULL, |
920d2a44 | 921 | show_coerce_float_to_double_p, |
2c5b56ce | 922 | &setlist, &showlist); |
04714b91 AC |
923 | |
924 | add_setshow_boolean_cmd ("unwindonsignal", no_class, | |
7915a72c AC |
925 | &unwind_on_signal_p, _("\ |
926 | Set unwinding of stack if a signal is received while in a call dummy."), _("\ | |
927 | Show unwinding of stack if a signal is received while in a call dummy."), _("\ | |
04714b91 AC |
928 | The unwindonsignal lets the user determine what gdb should do if a signal\n\ |
929 | is received while in a function called from gdb (call dummy). If set, gdb\n\ | |
930 | unwinds the stack and restore the context to what as it was before the call.\n\ | |
7915a72c | 931 | The default is to stop in the frame where the signal was received."), |
2c5b56ce | 932 | NULL, |
920d2a44 | 933 | show_unwind_on_signal_p, |
2c5b56ce | 934 | &setlist, &showlist); |
04714b91 | 935 | } |