Commit | Line | Data |
---|---|---|
04714b91 AC |
1 | /* Perform an inferior function call, for GDB, the GNU debugger. |
2 | ||
42a4f53d | 3 | Copyright (C) 1986-2019 Free Software Foundation, Inc. |
04714b91 AC |
4 | |
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
04714b91 AC |
10 | (at your option) any later version. |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
04714b91 AC |
19 | |
20 | #include "defs.h" | |
0700e23e | 21 | #include "infcall.h" |
04714b91 | 22 | #include "breakpoint.h" |
573cda03 | 23 | #include "tracepoint.h" |
04714b91 AC |
24 | #include "target.h" |
25 | #include "regcache.h" | |
26 | #include "inferior.h" | |
45741a9c | 27 | #include "infrun.h" |
04714b91 AC |
28 | #include "block.h" |
29 | #include "gdbcore.h" | |
30 | #include "language.h" | |
9ab9195f | 31 | #include "objfiles.h" |
04714b91 AC |
32 | #include "gdbcmd.h" |
33 | #include "command.h" | |
96860204 | 34 | #include "dummy-frame.h" |
a93c0eb6 | 35 | #include "ada-lang.h" |
347bddb7 | 36 | #include "gdbthread.h" |
beb460e8 | 37 | #include "event-top.h" |
76727919 | 38 | #include "observable.h" |
0b333c5e PA |
39 | #include "top.h" |
40 | #include "interps.h" | |
388a7084 | 41 | #include "thread-fsm.h" |
6ccb583f | 42 | #include <algorithm> |
2cc83d1e | 43 | #include "common/scope-exit.h" |
b89667eb DE |
44 | |
45 | /* If we can't find a function's name from its address, | |
46 | we print this instead. */ | |
47 | #define RAW_FUNCTION_ADDRESS_FORMAT "at 0x%s" | |
48 | #define RAW_FUNCTION_ADDRESS_SIZE (sizeof (RAW_FUNCTION_ADDRESS_FORMAT) \ | |
49 | + 2 * sizeof (CORE_ADDR)) | |
04714b91 AC |
50 | |
51 | /* NOTE: cagney/2003-04-16: What's the future of this code? | |
52 | ||
53 | GDB needs an asynchronous expression evaluator, that means an | |
54 | asynchronous inferior function call implementation, and that in | |
55 | turn means restructuring the code so that it is event driven. */ | |
56 | ||
57 | /* How you should pass arguments to a function depends on whether it | |
58 | was defined in K&R style or prototype style. If you define a | |
59 | function using the K&R syntax that takes a `float' argument, then | |
60 | callers must pass that argument as a `double'. If you define the | |
61 | function using the prototype syntax, then you must pass the | |
62 | argument as a `float', with no promotion. | |
63 | ||
64 | Unfortunately, on certain older platforms, the debug info doesn't | |
65 | indicate reliably how each function was defined. A function type's | |
a9ff5f12 UW |
66 | TYPE_PROTOTYPED flag may be clear, even if the function was defined |
67 | in prototype style. When calling a function whose TYPE_PROTOTYPED | |
68 | flag is clear, GDB consults this flag to decide what to do. | |
04714b91 AC |
69 | |
70 | For modern targets, it is proper to assume that, if the prototype | |
71 | flag is clear, that can be trusted: `float' arguments should be | |
72 | promoted to `double'. For some older targets, if the prototype | |
73 | flag is clear, that doesn't tell us anything. The default is to | |
74 | trust the debug information; the user can override this behavior | |
75 | with "set coerce-float-to-double 0". */ | |
76 | ||
77 | static int coerce_float_to_double_p = 1; | |
920d2a44 AC |
78 | static void |
79 | show_coerce_float_to_double_p (struct ui_file *file, int from_tty, | |
80 | struct cmd_list_element *c, const char *value) | |
81 | { | |
3e43a32a MS |
82 | fprintf_filtered (file, |
83 | _("Coercion of floats to doubles " | |
84 | "when calling functions is %s.\n"), | |
920d2a44 AC |
85 | value); |
86 | } | |
04714b91 AC |
87 | |
88 | /* This boolean tells what gdb should do if a signal is received while | |
89 | in a function called from gdb (call dummy). If set, gdb unwinds | |
90 | the stack and restore the context to what as it was before the | |
91 | call. | |
92 | ||
1777feb0 | 93 | The default is to stop in the frame where the signal was received. */ |
04714b91 | 94 | |
ef61f180 | 95 | static int unwind_on_signal_p = 0; |
920d2a44 AC |
96 | static void |
97 | show_unwind_on_signal_p (struct ui_file *file, int from_tty, | |
98 | struct cmd_list_element *c, const char *value) | |
99 | { | |
3e43a32a MS |
100 | fprintf_filtered (file, |
101 | _("Unwinding of stack if a signal is " | |
102 | "received while in a call dummy is %s.\n"), | |
920d2a44 AC |
103 | value); |
104 | } | |
105 | ||
7cd1089b PM |
106 | /* This boolean tells what gdb should do if a std::terminate call is |
107 | made while in a function called from gdb (call dummy). | |
108 | As the confines of a single dummy stack prohibit out-of-frame | |
109 | handlers from handling a raised exception, and as out-of-frame | |
110 | handlers are common in C++, this can lead to no handler being found | |
111 | by the unwinder, and a std::terminate call. This is a false positive. | |
112 | If set, gdb unwinds the stack and restores the context to what it | |
113 | was before the call. | |
114 | ||
115 | The default is to unwind the frame if a std::terminate call is | |
116 | made. */ | |
117 | ||
118 | static int unwind_on_terminating_exception_p = 1; | |
119 | ||
120 | static void | |
121 | show_unwind_on_terminating_exception_p (struct ui_file *file, int from_tty, | |
122 | struct cmd_list_element *c, | |
123 | const char *value) | |
124 | ||
125 | { | |
3e43a32a MS |
126 | fprintf_filtered (file, |
127 | _("Unwind stack if a C++ exception is " | |
128 | "unhandled while in a call dummy is %s.\n"), | |
7cd1089b PM |
129 | value); |
130 | } | |
04714b91 AC |
131 | |
132 | /* Perform the standard coercions that are specified | |
a93c0eb6 | 133 | for arguments to be passed to C or Ada functions. |
04714b91 AC |
134 | |
135 | If PARAM_TYPE is non-NULL, it is the expected parameter type. | |
a93c0eb6 JB |
136 | IS_PROTOTYPED is non-zero if the function declaration is prototyped. |
137 | SP is the stack pointer were additional data can be pushed (updating | |
138 | its value as needed). */ | |
04714b91 AC |
139 | |
140 | static struct value * | |
7788af6d UW |
141 | value_arg_coerce (struct gdbarch *gdbarch, struct value *arg, |
142 | struct type *param_type, int is_prototyped, CORE_ADDR *sp) | |
04714b91 | 143 | { |
7788af6d | 144 | const struct builtin_type *builtin = builtin_type (gdbarch); |
df407dfe | 145 | struct type *arg_type = check_typedef (value_type (arg)); |
52f0bd74 | 146 | struct type *type |
04714b91 AC |
147 | = param_type ? check_typedef (param_type) : arg_type; |
148 | ||
a93c0eb6 JB |
149 | /* Perform any Ada-specific coercion first. */ |
150 | if (current_language->la_language == language_ada) | |
40bc484c | 151 | arg = ada_convert_actual (arg, type); |
a93c0eb6 | 152 | |
63092375 DJ |
153 | /* Force the value to the target if we will need its address. At |
154 | this point, we could allocate arguments on the stack instead of | |
155 | calling malloc if we knew that their addresses would not be | |
156 | saved by the called function. */ | |
157 | arg = value_coerce_to_target (arg); | |
158 | ||
04714b91 AC |
159 | switch (TYPE_CODE (type)) |
160 | { | |
161 | case TYPE_CODE_REF: | |
aa006118 | 162 | case TYPE_CODE_RVALUE_REF: |
fb933624 DJ |
163 | { |
164 | struct value *new_value; | |
165 | ||
aa006118 | 166 | if (TYPE_IS_REFERENCE (arg_type)) |
b1af9e97 | 167 | return value_cast_pointers (type, arg, 0); |
fb933624 DJ |
168 | |
169 | /* Cast the value to the reference's target type, and then | |
170 | convert it back to a reference. This will issue an error | |
171 | if the value was not previously in memory - in some cases | |
172 | we should clearly be allowing this, but how? */ | |
173 | new_value = value_cast (TYPE_TARGET_TYPE (type), arg); | |
a65cfae5 | 174 | new_value = value_ref (new_value, TYPE_CODE (type)); |
fb933624 DJ |
175 | return new_value; |
176 | } | |
04714b91 AC |
177 | case TYPE_CODE_INT: |
178 | case TYPE_CODE_CHAR: | |
179 | case TYPE_CODE_BOOL: | |
180 | case TYPE_CODE_ENUM: | |
181 | /* If we don't have a prototype, coerce to integer type if necessary. */ | |
182 | if (!is_prototyped) | |
183 | { | |
7788af6d UW |
184 | if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin->builtin_int)) |
185 | type = builtin->builtin_int; | |
04714b91 AC |
186 | } |
187 | /* Currently all target ABIs require at least the width of an integer | |
188 | type for an argument. We may have to conditionalize the following | |
189 | type coercion for future targets. */ | |
7788af6d UW |
190 | if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin->builtin_int)) |
191 | type = builtin->builtin_int; | |
04714b91 AC |
192 | break; |
193 | case TYPE_CODE_FLT: | |
194 | if (!is_prototyped && coerce_float_to_double_p) | |
195 | { | |
7788af6d UW |
196 | if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin->builtin_double)) |
197 | type = builtin->builtin_double; | |
198 | else if (TYPE_LENGTH (type) > TYPE_LENGTH (builtin->builtin_double)) | |
199 | type = builtin->builtin_long_double; | |
04714b91 AC |
200 | } |
201 | break; | |
202 | case TYPE_CODE_FUNC: | |
203 | type = lookup_pointer_type (type); | |
204 | break; | |
205 | case TYPE_CODE_ARRAY: | |
206 | /* Arrays are coerced to pointers to their first element, unless | |
207 | they are vectors, in which case we want to leave them alone, | |
208 | because they are passed by value. */ | |
209 | if (current_language->c_style_arrays) | |
210 | if (!TYPE_VECTOR (type)) | |
211 | type = lookup_pointer_type (TYPE_TARGET_TYPE (type)); | |
212 | break; | |
213 | case TYPE_CODE_UNDEF: | |
214 | case TYPE_CODE_PTR: | |
215 | case TYPE_CODE_STRUCT: | |
216 | case TYPE_CODE_UNION: | |
217 | case TYPE_CODE_VOID: | |
218 | case TYPE_CODE_SET: | |
219 | case TYPE_CODE_RANGE: | |
220 | case TYPE_CODE_STRING: | |
04714b91 | 221 | case TYPE_CODE_ERROR: |
0d5de010 DJ |
222 | case TYPE_CODE_MEMBERPTR: |
223 | case TYPE_CODE_METHODPTR: | |
04714b91 AC |
224 | case TYPE_CODE_METHOD: |
225 | case TYPE_CODE_COMPLEX: | |
226 | default: | |
227 | break; | |
228 | } | |
229 | ||
230 | return value_cast (type, arg); | |
231 | } | |
232 | ||
8388016d | 233 | /* See infcall.h. */ |
04714b91 | 234 | |
a9fa03de | 235 | CORE_ADDR |
8388016d PA |
236 | find_function_addr (struct value *function, |
237 | struct type **retval_type, | |
238 | struct type **function_type) | |
04714b91 | 239 | { |
df407dfe | 240 | struct type *ftype = check_typedef (value_type (function)); |
50810684 | 241 | struct gdbarch *gdbarch = get_type_arch (ftype); |
7788af6d | 242 | struct type *value_type = NULL; |
09b58708 JK |
243 | /* Initialize it just to avoid a GCC false warning. */ |
244 | CORE_ADDR funaddr = 0; | |
04714b91 AC |
245 | |
246 | /* If it's a member function, just look at the function | |
247 | part of it. */ | |
248 | ||
249 | /* Determine address to call. */ | |
300f8e10 JK |
250 | if (TYPE_CODE (ftype) == TYPE_CODE_FUNC |
251 | || TYPE_CODE (ftype) == TYPE_CODE_METHOD) | |
252 | funaddr = value_address (function); | |
253 | else if (TYPE_CODE (ftype) == TYPE_CODE_PTR) | |
04714b91 AC |
254 | { |
255 | funaddr = value_as_address (function); | |
256 | ftype = check_typedef (TYPE_TARGET_TYPE (ftype)); | |
257 | if (TYPE_CODE (ftype) == TYPE_CODE_FUNC | |
258 | || TYPE_CODE (ftype) == TYPE_CODE_METHOD) | |
300f8e10 | 259 | funaddr = gdbarch_convert_from_func_ptr_addr (gdbarch, funaddr, |
8b88a78e | 260 | current_top_target ()); |
04714b91 | 261 | } |
300f8e10 JK |
262 | if (TYPE_CODE (ftype) == TYPE_CODE_FUNC |
263 | || TYPE_CODE (ftype) == TYPE_CODE_METHOD) | |
07be84bf | 264 | { |
07be84bf JK |
265 | if (TYPE_GNU_IFUNC (ftype)) |
266 | { | |
8388016d | 267 | CORE_ADDR resolver_addr = funaddr; |
07be84bf | 268 | |
8388016d PA |
269 | /* Resolve the ifunc. Note this may call the resolver |
270 | function in the inferior. */ | |
271 | funaddr = gnu_ifunc_resolve_addr (gdbarch, resolver_addr); | |
272 | ||
273 | /* Skip querying the function symbol if no RETVAL_TYPE or | |
274 | FUNCTION_TYPE have been asked for. */ | |
275 | if (retval_type != NULL || function_type != NULL) | |
276 | { | |
277 | type *target_ftype = find_function_type (funaddr); | |
278 | /* If we don't have debug info for the target function, | |
279 | see if we can instead extract the target function's | |
280 | type from the type that the resolver returns. */ | |
281 | if (target_ftype == NULL) | |
282 | target_ftype = find_gnu_ifunc_target_type (resolver_addr); | |
283 | if (target_ftype != NULL) | |
284 | { | |
285 | value_type = TYPE_TARGET_TYPE (check_typedef (target_ftype)); | |
286 | ftype = target_ftype; | |
287 | } | |
288 | } | |
07be84bf | 289 | } |
8388016d PA |
290 | else |
291 | value_type = TYPE_TARGET_TYPE (ftype); | |
07be84bf | 292 | } |
300f8e10 | 293 | else if (TYPE_CODE (ftype) == TYPE_CODE_INT) |
04714b91 AC |
294 | { |
295 | /* Handle the case of functions lacking debugging info. | |
1777feb0 | 296 | Their values are characters since their addresses are char. */ |
04714b91 AC |
297 | if (TYPE_LENGTH (ftype) == 1) |
298 | funaddr = value_as_address (value_addr (function)); | |
299 | else | |
2bbe3cc1 DJ |
300 | { |
301 | /* Handle function descriptors lacking debug info. */ | |
302 | int found_descriptor = 0; | |
abbb1732 | 303 | |
87bc73ea | 304 | funaddr = 0; /* pacify "gcc -Werror" */ |
2bbe3cc1 DJ |
305 | if (VALUE_LVAL (function) == lval_memory) |
306 | { | |
307 | CORE_ADDR nfunaddr; | |
abbb1732 | 308 | |
2bbe3cc1 DJ |
309 | funaddr = value_as_address (value_addr (function)); |
310 | nfunaddr = funaddr; | |
8b88a78e PA |
311 | funaddr |
312 | = gdbarch_convert_from_func_ptr_addr (gdbarch, funaddr, | |
313 | current_top_target ()); | |
2bbe3cc1 DJ |
314 | if (funaddr != nfunaddr) |
315 | found_descriptor = 1; | |
316 | } | |
317 | if (!found_descriptor) | |
318 | /* Handle integer used as address of a function. */ | |
319 | funaddr = (CORE_ADDR) value_as_long (function); | |
320 | } | |
04714b91 AC |
321 | } |
322 | else | |
8a3fe4f8 | 323 | error (_("Invalid data type for function to be called.")); |
04714b91 | 324 | |
7d9b040b RC |
325 | if (retval_type != NULL) |
326 | *retval_type = value_type; | |
8388016d PA |
327 | if (function_type != NULL) |
328 | *function_type = ftype; | |
50810684 | 329 | return funaddr + gdbarch_deprecated_function_start_offset (gdbarch); |
04714b91 AC |
330 | } |
331 | ||
d3712828 AC |
332 | /* For CALL_DUMMY_ON_STACK, push a breakpoint sequence that the called |
333 | function returns to. */ | |
7043d8dc AC |
334 | |
335 | static CORE_ADDR | |
336 | push_dummy_code (struct gdbarch *gdbarch, | |
82585c72 | 337 | CORE_ADDR sp, CORE_ADDR funaddr, |
e71585ff | 338 | gdb::array_view<value *> args, |
7043d8dc | 339 | struct type *value_type, |
e4fd649a UW |
340 | CORE_ADDR *real_pc, CORE_ADDR *bp_addr, |
341 | struct regcache *regcache) | |
7043d8dc | 342 | { |
50a834af MK |
343 | gdb_assert (gdbarch_push_dummy_code_p (gdbarch)); |
344 | ||
345 | return gdbarch_push_dummy_code (gdbarch, sp, funaddr, | |
e71585ff PA |
346 | args.data (), args.size (), |
347 | value_type, real_pc, bp_addr, | |
50a834af | 348 | regcache); |
7043d8dc AC |
349 | } |
350 | ||
7022349d PA |
351 | /* See infcall.h. */ |
352 | ||
353 | void | |
354 | error_call_unknown_return_type (const char *func_name) | |
355 | { | |
356 | if (func_name != NULL) | |
357 | error (_("'%s' has unknown return type; " | |
358 | "cast the call to its declared return type"), | |
359 | func_name); | |
360 | else | |
361 | error (_("function has unknown return type; " | |
362 | "cast the call to its declared return type")); | |
363 | } | |
364 | ||
b89667eb DE |
365 | /* Fetch the name of the function at FUNADDR. |
366 | This is used in printing an error message for call_function_by_hand. | |
367 | BUF is used to print FUNADDR in hex if the function name cannot be | |
368 | determined. It must be large enough to hold formatted result of | |
369 | RAW_FUNCTION_ADDRESS_FORMAT. */ | |
370 | ||
371 | static const char * | |
372 | get_function_name (CORE_ADDR funaddr, char *buf, int buf_size) | |
373 | { | |
374 | { | |
375 | struct symbol *symbol = find_pc_function (funaddr); | |
abbb1732 | 376 | |
b89667eb DE |
377 | if (symbol) |
378 | return SYMBOL_PRINT_NAME (symbol); | |
379 | } | |
380 | ||
381 | { | |
382 | /* Try the minimal symbols. */ | |
7cbd4a93 | 383 | struct bound_minimal_symbol msymbol = lookup_minimal_symbol_by_pc (funaddr); |
abbb1732 | 384 | |
7cbd4a93 | 385 | if (msymbol.minsym) |
efd66ac6 | 386 | return MSYMBOL_PRINT_NAME (msymbol.minsym); |
b89667eb DE |
387 | } |
388 | ||
389 | { | |
528e1572 SM |
390 | std::string tmp = string_printf (_(RAW_FUNCTION_ADDRESS_FORMAT), |
391 | hex_string (funaddr)); | |
abbb1732 | 392 | |
528e1572 SM |
393 | gdb_assert (tmp.length () + 1 <= buf_size); |
394 | return strcpy (buf, tmp.c_str ()); | |
b89667eb DE |
395 | } |
396 | } | |
397 | ||
388a7084 PA |
398 | /* All the meta data necessary to extract the call's return value. */ |
399 | ||
400 | struct call_return_meta_info | |
401 | { | |
402 | /* The caller frame's architecture. */ | |
403 | struct gdbarch *gdbarch; | |
404 | ||
405 | /* The called function. */ | |
406 | struct value *function; | |
407 | ||
408 | /* The return value's type. */ | |
409 | struct type *value_type; | |
410 | ||
411 | /* Are we returning a value using a structure return or a normal | |
412 | value return? */ | |
413 | int struct_return_p; | |
414 | ||
415 | /* If using a structure return, this is the structure's address. */ | |
416 | CORE_ADDR struct_addr; | |
388a7084 PA |
417 | }; |
418 | ||
419 | /* Extract the called function's return value. */ | |
420 | ||
421 | static struct value * | |
422 | get_call_return_value (struct call_return_meta_info *ri) | |
423 | { | |
424 | struct value *retval = NULL; | |
00431a78 PA |
425 | thread_info *thr = inferior_thread (); |
426 | bool stack_temporaries = thread_stack_temporaries_enabled_p (thr); | |
388a7084 PA |
427 | |
428 | if (TYPE_CODE (ri->value_type) == TYPE_CODE_VOID) | |
429 | retval = allocate_value (ri->value_type); | |
430 | else if (ri->struct_return_p) | |
431 | { | |
432 | if (stack_temporaries) | |
433 | { | |
434 | retval = value_from_contents_and_address (ri->value_type, NULL, | |
435 | ri->struct_addr); | |
00431a78 | 436 | push_thread_stack_temporary (thr, retval); |
388a7084 PA |
437 | } |
438 | else | |
439 | { | |
440 | retval = allocate_value (ri->value_type); | |
441 | read_value_memory (retval, 0, 1, ri->struct_addr, | |
442 | value_contents_raw (retval), | |
443 | TYPE_LENGTH (ri->value_type)); | |
444 | } | |
445 | } | |
446 | else | |
447 | { | |
448 | retval = allocate_value (ri->value_type); | |
449 | gdbarch_return_value (ri->gdbarch, ri->function, ri->value_type, | |
450 | get_current_regcache (), | |
451 | value_contents_raw (retval), NULL); | |
452 | if (stack_temporaries && class_or_union_p (ri->value_type)) | |
453 | { | |
454 | /* Values of class type returned in registers are copied onto | |
455 | the stack and their lval_type set to lval_memory. This is | |
456 | required because further evaluation of the expression | |
457 | could potentially invoke methods on the return value | |
458 | requiring GDB to evaluate the "this" pointer. To evaluate | |
459 | the this pointer, GDB needs the memory address of the | |
460 | value. */ | |
461 | value_force_lval (retval, ri->struct_addr); | |
00431a78 | 462 | push_thread_stack_temporary (thr, retval); |
388a7084 PA |
463 | } |
464 | } | |
465 | ||
466 | gdb_assert (retval != NULL); | |
467 | return retval; | |
468 | } | |
469 | ||
470 | /* Data for the FSM that manages an infcall. It's main job is to | |
471 | record the called function's return value. */ | |
472 | ||
46e3ed7f | 473 | struct call_thread_fsm : public thread_fsm |
388a7084 | 474 | { |
388a7084 PA |
475 | /* All the info necessary to be able to extract the return |
476 | value. */ | |
477 | struct call_return_meta_info return_meta_info; | |
478 | ||
479 | /* The called function's return value. This is extracted from the | |
480 | target before the dummy frame is popped. */ | |
46e3ed7f | 481 | struct value *return_value = nullptr; |
3b12939d PA |
482 | |
483 | /* The top level that started the infcall (and is synchronously | |
484 | waiting for it to end). */ | |
485 | struct ui *waiting_ui; | |
388a7084 | 486 | |
46e3ed7f TT |
487 | call_thread_fsm (struct ui *waiting_ui, struct interp *cmd_interp, |
488 | struct gdbarch *gdbarch, struct value *function, | |
489 | struct type *value_type, | |
490 | int struct_return_p, CORE_ADDR struct_addr); | |
388a7084 | 491 | |
46e3ed7f | 492 | bool should_stop (struct thread_info *thread) override; |
388a7084 | 493 | |
46e3ed7f | 494 | bool should_notify_stop () override; |
388a7084 PA |
495 | }; |
496 | ||
497 | /* Allocate a new call_thread_fsm object. */ | |
498 | ||
46e3ed7f TT |
499 | call_thread_fsm::call_thread_fsm (struct ui *waiting_ui, |
500 | struct interp *cmd_interp, | |
501 | struct gdbarch *gdbarch, | |
502 | struct value *function, | |
503 | struct type *value_type, | |
504 | int struct_return_p, CORE_ADDR struct_addr) | |
505 | : thread_fsm (cmd_interp), | |
506 | waiting_ui (waiting_ui) | |
388a7084 | 507 | { |
46e3ed7f TT |
508 | return_meta_info.gdbarch = gdbarch; |
509 | return_meta_info.function = function; | |
510 | return_meta_info.value_type = value_type; | |
511 | return_meta_info.struct_return_p = struct_return_p; | |
512 | return_meta_info.struct_addr = struct_addr; | |
388a7084 PA |
513 | } |
514 | ||
515 | /* Implementation of should_stop method for infcalls. */ | |
516 | ||
46e3ed7f TT |
517 | bool |
518 | call_thread_fsm::should_stop (struct thread_info *thread) | |
388a7084 | 519 | { |
388a7084 PA |
520 | if (stop_stack_dummy == STOP_STACK_DUMMY) |
521 | { | |
522 | /* Done. */ | |
46e3ed7f | 523 | set_finished (); |
388a7084 PA |
524 | |
525 | /* Stash the return value before the dummy frame is popped and | |
526 | registers are restored to what they were before the | |
527 | call.. */ | |
46e3ed7f | 528 | return_value = get_call_return_value (&return_meta_info); |
388a7084 PA |
529 | |
530 | /* Break out of wait_sync_command_done. */ | |
46e3ed7f | 531 | scoped_restore save_ui = make_scoped_restore (¤t_ui, waiting_ui); |
223ffa71 | 532 | target_terminal::ours (); |
46e3ed7f | 533 | waiting_ui->prompt_state = PROMPT_NEEDED; |
388a7084 PA |
534 | } |
535 | ||
46e3ed7f | 536 | return true; |
388a7084 PA |
537 | } |
538 | ||
539 | /* Implementation of should_notify_stop method for infcalls. */ | |
540 | ||
46e3ed7f TT |
541 | bool |
542 | call_thread_fsm::should_notify_stop () | |
388a7084 | 543 | { |
46e3ed7f | 544 | if (finished_p ()) |
388a7084 PA |
545 | { |
546 | /* Infcall succeeded. Be silent and proceed with evaluating the | |
547 | expression. */ | |
46e3ed7f | 548 | return false; |
388a7084 PA |
549 | } |
550 | ||
551 | /* Something wrong happened. E.g., an unexpected breakpoint | |
552 | triggered, or a signal was intercepted. Notify the stop. */ | |
46e3ed7f | 553 | return true; |
388a7084 PA |
554 | } |
555 | ||
b89667eb DE |
556 | /* Subroutine of call_function_by_hand to simplify it. |
557 | Start up the inferior and wait for it to stop. | |
558 | Return the exception if there's an error, or an exception with | |
559 | reason >= 0 if there's no error. | |
560 | ||
561 | This is done inside a TRY_CATCH so the caller needn't worry about | |
562 | thrown errors. The caller should rethrow if there's an error. */ | |
563 | ||
564 | static struct gdb_exception | |
388a7084 PA |
565 | run_inferior_call (struct call_thread_fsm *sm, |
566 | struct thread_info *call_thread, CORE_ADDR real_pc) | |
b89667eb | 567 | { |
492d29ea | 568 | struct gdb_exception caught_error = exception_none; |
16c381f0 | 569 | int saved_in_infcall = call_thread->control.in_infcall; |
b89667eb | 570 | ptid_t call_thread_ptid = call_thread->ptid; |
3b12939d | 571 | enum prompt_state saved_prompt_state = current_ui->prompt_state; |
28bf096c | 572 | int was_running = call_thread->state == THREAD_RUNNING; |
cb814510 | 573 | int saved_ui_async = current_ui->async; |
c933f875 PA |
574 | |
575 | /* Infcalls run synchronously, in the foreground. */ | |
3b12939d | 576 | current_ui->prompt_state = PROMPT_BLOCKED; |
0b333c5e PA |
577 | /* So that we don't print the prompt prematurely in |
578 | fetch_inferior_event. */ | |
cb814510 | 579 | current_ui->async = 0; |
b89667eb | 580 | |
6d61dee5 PA |
581 | delete_file_handler (current_ui->input_fd); |
582 | ||
16c381f0 | 583 | call_thread->control.in_infcall = 1; |
c5a4d20b | 584 | |
70509625 | 585 | clear_proceed_status (0); |
b89667eb | 586 | |
388a7084 PA |
587 | /* Associate the FSM with the thread after clear_proceed_status |
588 | (otherwise it'd clear this FSM), and before anything throws, so | |
589 | we don't leak it (and any resources it manages). */ | |
46e3ed7f | 590 | call_thread->thread_fsm = sm; |
388a7084 | 591 | |
b89667eb | 592 | disable_watchpoints_before_interactive_call_start (); |
16c381f0 | 593 | |
46c03469 | 594 | /* We want to print return value, please... */ |
16c381f0 | 595 | call_thread->control.proceed_to_finish = 1; |
b89667eb | 596 | |
492d29ea | 597 | TRY |
3dd5b83d | 598 | { |
64ce06e4 | 599 | proceed (real_pc, GDB_SIGNAL_0); |
3dd5b83d PA |
600 | |
601 | /* Inferior function calls are always synchronous, even if the | |
0b333c5e PA |
602 | target supports asynchronous execution. */ |
603 | wait_sync_command_done (); | |
3dd5b83d | 604 | } |
492d29ea PA |
605 | CATCH (e, RETURN_MASK_ALL) |
606 | { | |
607 | caught_error = e; | |
608 | } | |
609 | END_CATCH | |
b89667eb | 610 | |
3b12939d PA |
611 | /* If GDB has the prompt blocked before, then ensure that it remains |
612 | so. normal_stop calls async_enable_stdin, so reset the prompt | |
613 | state again here. In other cases, stdin will be re-enabled by | |
0b333c5e | 614 | inferior_event_handler, when an exception is thrown. */ |
3b12939d | 615 | current_ui->prompt_state = saved_prompt_state; |
6d61dee5 PA |
616 | if (current_ui->prompt_state == PROMPT_BLOCKED) |
617 | delete_file_handler (current_ui->input_fd); | |
618 | else | |
619 | ui_register_input_event_handler (current_ui); | |
cb814510 | 620 | current_ui->async = saved_ui_async; |
0b333c5e | 621 | |
28bf096c PA |
622 | /* If the infcall does NOT succeed, normal_stop will have already |
623 | finished the thread states. However, on success, normal_stop | |
624 | defers here, so that we can set back the thread states to what | |
625 | they were before the call. Note that we must also finish the | |
626 | state of new threads that might have spawned while the call was | |
627 | running. The main cases to handle are: | |
628 | ||
629 | - "(gdb) print foo ()", or any other command that evaluates an | |
630 | expression at the prompt. (The thread was marked stopped before.) | |
631 | ||
632 | - "(gdb) break foo if return_false()" or similar cases where we | |
633 | do an infcall while handling an event (while the thread is still | |
634 | marked running). In this example, whether the condition | |
635 | evaluates true and thus we'll present a user-visible stop is | |
636 | decided elsewhere. */ | |
637 | if (!was_running | |
00431a78 | 638 | && call_thread_ptid == inferior_ptid |
28bf096c PA |
639 | && stop_stack_dummy == STOP_STACK_DUMMY) |
640 | finish_thread_state (user_visible_resume_ptid (0)); | |
641 | ||
b89667eb DE |
642 | enable_watchpoints_after_interactive_call_stop (); |
643 | ||
644 | /* Call breakpoint_auto_delete on the current contents of the bpstat | |
645 | of inferior call thread. | |
646 | If all error()s out of proceed ended up calling normal_stop | |
647 | (and perhaps they should; it already does in the special case | |
648 | of error out of resume()), then we wouldn't need this. */ | |
492d29ea | 649 | if (caught_error.reason < 0) |
b89667eb | 650 | { |
00431a78 | 651 | if (call_thread->state != THREAD_EXITED) |
16c381f0 | 652 | breakpoint_auto_delete (call_thread->control.stop_bpstat); |
b89667eb DE |
653 | } |
654 | ||
00431a78 | 655 | call_thread->control.in_infcall = saved_in_infcall; |
c5a4d20b | 656 | |
492d29ea | 657 | return caught_error; |
b89667eb DE |
658 | } |
659 | ||
ed12ef62 JK |
660 | /* See infcall.h. */ |
661 | ||
662 | struct value * | |
7022349d PA |
663 | call_function_by_hand (struct value *function, |
664 | type *default_return_type, | |
e71585ff | 665 | gdb::array_view<value *> args) |
ed12ef62 | 666 | { |
7022349d | 667 | return call_function_by_hand_dummy (function, default_return_type, |
e71585ff | 668 | args, NULL, NULL); |
ed12ef62 JK |
669 | } |
670 | ||
04714b91 AC |
671 | /* All this stuff with a dummy frame may seem unnecessarily complicated |
672 | (why not just save registers in GDB?). The purpose of pushing a dummy | |
673 | frame which looks just like a real frame is so that if you call a | |
674 | function and then hit a breakpoint (get a signal, etc), "backtrace" | |
675 | will look right. Whether the backtrace needs to actually show the | |
676 | stack at the time the inferior function was called is debatable, but | |
677 | it certainly needs to not display garbage. So if you are contemplating | |
678 | making dummy frames be different from normal frames, consider that. */ | |
679 | ||
680 | /* Perform a function call in the inferior. | |
681 | ARGS is a vector of values of arguments (NARGS of them). | |
682 | FUNCTION is a value, the function to be called. | |
683 | Returns a value representing what the function returned. | |
684 | May fail to return, if a breakpoint or signal is hit | |
685 | during the execution of the function. | |
686 | ||
1777feb0 | 687 | ARGS is modified to contain coerced values. */ |
04714b91 AC |
688 | |
689 | struct value * | |
ed12ef62 | 690 | call_function_by_hand_dummy (struct value *function, |
7022349d | 691 | type *default_return_type, |
e71585ff | 692 | gdb::array_view<value *> args, |
558e5469 | 693 | dummy_frame_dtor_ftype *dummy_dtor, |
ed12ef62 | 694 | void *dummy_dtor_data) |
04714b91 | 695 | { |
52f0bd74 | 696 | CORE_ADDR sp; |
8388016d | 697 | struct type *target_values_type; |
c5ac5cbb | 698 | function_call_return_method return_method = return_method_normal; |
04714b91 | 699 | CORE_ADDR struct_addr = 0; |
04714b91 | 700 | CORE_ADDR real_pc; |
d585e13a | 701 | CORE_ADDR bp_addr; |
96860204 | 702 | struct frame_id dummy_id; |
0b9dfe2b MD |
703 | struct frame_info *frame; |
704 | struct gdbarch *gdbarch; | |
b89667eb DE |
705 | ptid_t call_thread_ptid; |
706 | struct gdb_exception e; | |
b89667eb | 707 | char name_buf[RAW_FUNCTION_ADDRESS_SIZE]; |
04714b91 | 708 | |
04714b91 AC |
709 | if (!target_has_execution) |
710 | noprocess (); | |
711 | ||
573cda03 SS |
712 | if (get_traceframe_number () >= 0) |
713 | error (_("May not call functions while looking at trace frames.")); | |
714 | ||
949dc678 | 715 | if (execution_direction == EXEC_REVERSE) |
c2949be0 | 716 | error (_("Cannot call functions in reverse mode.")); |
949dc678 | 717 | |
00431a78 PA |
718 | /* We're going to run the target, and inspect the thread's state |
719 | afterwards. Hold a strong reference so that the pointer remains | |
720 | valid even if the thread exits. */ | |
721 | thread_info_ref call_thread | |
722 | = thread_info_ref::new_reference (inferior_thread ()); | |
723 | ||
724 | bool stack_temporaries = thread_stack_temporaries_enabled_p (call_thread.get ()); | |
725 | ||
0b9dfe2b MD |
726 | frame = get_current_frame (); |
727 | gdbarch = get_frame_arch (frame); | |
728 | ||
729 | if (!gdbarch_push_dummy_call_p (gdbarch)) | |
2e74121d | 730 | error (_("This target does not support function calls.")); |
a86c5fc9 | 731 | |
c7c4d3fa | 732 | /* A holder for the inferior status. |
b89667eb | 733 | This is only needed while we're preparing the inferior function call. */ |
c7c4d3fa | 734 | infcall_control_state_up inf_status (save_infcall_control_state ()); |
04714b91 | 735 | |
b89667eb DE |
736 | /* Save the caller's registers and other state associated with the |
737 | inferior itself so that they can be restored once the | |
96860204 | 738 | callee returns. To allow nested calls the registers are (further |
c7c4d3fa TT |
739 | down) pushed onto a dummy frame stack. This unique pointer |
740 | is released once the regcache has been pushed). */ | |
741 | infcall_suspend_state_up caller_state (save_infcall_suspend_state ()); | |
04714b91 | 742 | |
04714b91 | 743 | /* Ensure that the initial SP is correctly aligned. */ |
ebc7896c | 744 | { |
0b9dfe2b | 745 | CORE_ADDR old_sp = get_frame_sp (frame); |
abbb1732 | 746 | |
0b9dfe2b | 747 | if (gdbarch_frame_align_p (gdbarch)) |
ebc7896c | 748 | { |
0b9dfe2b | 749 | sp = gdbarch_frame_align (gdbarch, old_sp); |
8b148df9 AC |
750 | /* NOTE: cagney/2003-08-13: Skip the "red zone". For some |
751 | ABIs, a function can use memory beyond the inner most stack | |
752 | address. AMD64 called that region the "red zone". Skip at | |
753 | least the "red zone" size before allocating any space on | |
754 | the stack. */ | |
0b9dfe2b MD |
755 | if (gdbarch_inner_than (gdbarch, 1, 2)) |
756 | sp -= gdbarch_frame_red_zone_size (gdbarch); | |
8b148df9 | 757 | else |
0b9dfe2b | 758 | sp += gdbarch_frame_red_zone_size (gdbarch); |
8b148df9 | 759 | /* Still aligned? */ |
0b9dfe2b | 760 | gdb_assert (sp == gdbarch_frame_align (gdbarch, sp)); |
ebc7896c AC |
761 | /* NOTE: cagney/2002-09-18: |
762 | ||
763 | On a RISC architecture, a void parameterless generic dummy | |
764 | frame (i.e., no parameters, no result) typically does not | |
765 | need to push anything the stack and hence can leave SP and | |
c48a845b | 766 | FP. Similarly, a frameless (possibly leaf) function does |
ebc7896c AC |
767 | not push anything on the stack and, hence, that too can |
768 | leave FP and SP unchanged. As a consequence, a sequence of | |
769 | void parameterless generic dummy frame calls to frameless | |
770 | functions will create a sequence of effectively identical | |
771 | frames (SP, FP and TOS and PC the same). This, not | |
772 | suprisingly, results in what appears to be a stack in an | |
773 | infinite loop --- when GDB tries to find a generic dummy | |
774 | frame on the internal dummy frame stack, it will always | |
775 | find the first one. | |
776 | ||
777 | To avoid this problem, the code below always grows the | |
778 | stack. That way, two dummy frames can never be identical. | |
779 | It does burn a few bytes of stack but that is a small price | |
780 | to pay :-). */ | |
ebc7896c AC |
781 | if (sp == old_sp) |
782 | { | |
0b9dfe2b | 783 | if (gdbarch_inner_than (gdbarch, 1, 2)) |
ebc7896c | 784 | /* Stack grows down. */ |
0b9dfe2b | 785 | sp = gdbarch_frame_align (gdbarch, old_sp - 1); |
ebc7896c AC |
786 | else |
787 | /* Stack grows up. */ | |
0b9dfe2b | 788 | sp = gdbarch_frame_align (gdbarch, old_sp + 1); |
ebc7896c | 789 | } |
0e095b7e JK |
790 | /* SP may have underflown address zero here from OLD_SP. Memory access |
791 | functions will probably fail in such case but that is a target's | |
792 | problem. */ | |
ebc7896c AC |
793 | } |
794 | else | |
a59fe496 AC |
795 | /* FIXME: cagney/2002-09-18: Hey, you loose! |
796 | ||
8b148df9 AC |
797 | Who knows how badly aligned the SP is! |
798 | ||
799 | If the generic dummy frame ends up empty (because nothing is | |
800 | pushed) GDB won't be able to correctly perform back traces. | |
801 | If a target is having trouble with backtraces, first thing to | |
1777feb0 | 802 | do is add FRAME_ALIGN() to the architecture vector. If that |
669fac23 | 803 | fails, try dummy_id(). |
8b148df9 AC |
804 | |
805 | If the ABI specifies a "Red Zone" (see the doco) the code | |
806 | below will quietly trash it. */ | |
ebc7896c | 807 | sp = old_sp; |
6c659fc2 SC |
808 | |
809 | /* Skip over the stack temporaries that might have been generated during | |
810 | the evaluation of an expression. */ | |
811 | if (stack_temporaries) | |
812 | { | |
813 | struct value *lastval; | |
814 | ||
00431a78 | 815 | lastval = get_last_thread_stack_temporary (call_thread.get ()); |
6c659fc2 SC |
816 | if (lastval != NULL) |
817 | { | |
818 | CORE_ADDR lastval_addr = value_address (lastval); | |
819 | ||
820 | if (gdbarch_inner_than (gdbarch, 1, 2)) | |
821 | { | |
822 | gdb_assert (sp >= lastval_addr); | |
823 | sp = lastval_addr; | |
824 | } | |
825 | else | |
826 | { | |
827 | gdb_assert (sp <= lastval_addr); | |
828 | sp = lastval_addr + TYPE_LENGTH (value_type (lastval)); | |
829 | } | |
830 | ||
831 | if (gdbarch_frame_align_p (gdbarch)) | |
832 | sp = gdbarch_frame_align (gdbarch, sp); | |
833 | } | |
834 | } | |
ebc7896c | 835 | } |
04714b91 | 836 | |
8388016d PA |
837 | type *ftype; |
838 | type *values_type; | |
839 | CORE_ADDR funaddr = find_function_addr (function, &values_type, &ftype); | |
840 | ||
7022349d PA |
841 | if (values_type == NULL) |
842 | values_type = default_return_type; | |
843 | if (values_type == NULL) | |
844 | { | |
845 | const char *name = get_function_name (funaddr, | |
846 | name_buf, sizeof (name_buf)); | |
847 | error (_("'%s' has unknown return type; " | |
848 | "cast the call to its declared return type"), | |
849 | name); | |
850 | } | |
7788af6d | 851 | |
f168693b | 852 | values_type = check_typedef (values_type); |
04714b91 | 853 | |
c5ac5cbb | 854 | /* Are we returning a value using a structure return? */ |
41f1b697 | 855 | |
18648a37 | 856 | if (gdbarch_return_in_first_hidden_param_p (gdbarch, values_type)) |
41f1b697 | 857 | { |
c5ac5cbb | 858 | return_method = return_method_hidden_param; |
04714b91 | 859 | |
41f1b697 DJ |
860 | /* Tell the target specific argument pushing routine not to |
861 | expect a value. */ | |
48319d1f | 862 | target_values_type = builtin_type (gdbarch)->builtin_void; |
41f1b697 DJ |
863 | } |
864 | else | |
865 | { | |
c5ac5cbb AH |
866 | if (using_struct_return (gdbarch, function, values_type)) |
867 | return_method = return_method_struct; | |
41f1b697 DJ |
868 | target_values_type = values_type; |
869 | } | |
04714b91 | 870 | |
76727919 | 871 | gdb::observers::inferior_call_pre.notify (inferior_ptid, funaddr); |
162078c8 | 872 | |
7043d8dc AC |
873 | /* Determine the location of the breakpoint (and possibly other |
874 | stuff) that the called function will return to. The SPARC, for a | |
875 | function returning a structure or union, needs to make space for | |
876 | not just the breakpoint but also an extra word containing the | |
877 | size (?) of the structure being passed. */ | |
878 | ||
0b9dfe2b | 879 | switch (gdbarch_call_dummy_location (gdbarch)) |
04714b91 AC |
880 | { |
881 | case ON_STACK: | |
a14dd77e JK |
882 | { |
883 | const gdb_byte *bp_bytes; | |
884 | CORE_ADDR bp_addr_as_address; | |
885 | int bp_size; | |
886 | ||
887 | /* Be careful BP_ADDR is in inferior PC encoding while | |
888 | BP_ADDR_AS_ADDRESS is a plain memory address. */ | |
889 | ||
e71585ff | 890 | sp = push_dummy_code (gdbarch, sp, funaddr, args, |
a14dd77e JK |
891 | target_values_type, &real_pc, &bp_addr, |
892 | get_current_regcache ()); | |
893 | ||
894 | /* Write a legitimate instruction at the point where the infcall | |
895 | breakpoint is going to be inserted. While this instruction | |
896 | is never going to be executed, a user investigating the | |
897 | memory from GDB would see this instruction instead of random | |
898 | uninitialized bytes. We chose the breakpoint instruction | |
899 | as it may look as the most logical one to the user and also | |
900 | valgrind 3.7.0 needs it for proper vgdb inferior calls. | |
901 | ||
902 | If software breakpoints are unsupported for this target we | |
903 | leave the user visible memory content uninitialized. */ | |
904 | ||
905 | bp_addr_as_address = bp_addr; | |
906 | bp_bytes = gdbarch_breakpoint_from_pc (gdbarch, &bp_addr_as_address, | |
907 | &bp_size); | |
908 | if (bp_bytes != NULL) | |
909 | write_memory (bp_addr_as_address, bp_bytes, bp_size); | |
910 | } | |
7043d8dc | 911 | break; |
5931a2fa JK |
912 | case AT_ENTRY_POINT: |
913 | { | |
914 | CORE_ADDR dummy_addr; | |
915 | ||
916 | real_pc = funaddr; | |
917 | dummy_addr = entry_point_address (); | |
a14dd77e | 918 | |
5931a2fa | 919 | /* A call dummy always consists of just a single breakpoint, so |
a14dd77e JK |
920 | its address is the same as the address of the dummy. |
921 | ||
922 | The actual breakpoint is inserted separatly so there is no need to | |
923 | write that out. */ | |
5931a2fa JK |
924 | bp_addr = dummy_addr; |
925 | break; | |
926 | } | |
04714b91 | 927 | default: |
e2e0b3e5 | 928 | internal_error (__FILE__, __LINE__, _("bad switch")); |
04714b91 AC |
929 | } |
930 | ||
e71585ff | 931 | if (args.size () < TYPE_NFIELDS (ftype)) |
2e74121d | 932 | error (_("Too few arguments in function call.")); |
04714b91 | 933 | |
e71585ff | 934 | for (int i = args.size () - 1; i >= 0; i--) |
b4b08fa2 TT |
935 | { |
936 | int prototyped; | |
937 | struct type *param_type; | |
e71585ff | 938 | |
b4b08fa2 TT |
939 | /* FIXME drow/2002-05-31: Should just always mark methods as |
940 | prototyped. Can we respect TYPE_VARARGS? Probably not. */ | |
941 | if (TYPE_CODE (ftype) == TYPE_CODE_METHOD) | |
942 | prototyped = 1; | |
943 | if (TYPE_TARGET_TYPE (ftype) == NULL && TYPE_NFIELDS (ftype) == 0 | |
944 | && default_return_type != NULL) | |
945 | { | |
946 | /* Calling a no-debug function with the return type | |
947 | explicitly cast. Assume the function is prototyped, | |
948 | with a prototype matching the types of the arguments. | |
949 | E.g., with: | |
950 | float mult (float v1, float v2) { return v1 * v2; } | |
951 | This: | |
952 | (gdb) p (float) mult (2.0f, 3.0f) | |
953 | Is a simpler alternative to: | |
954 | (gdb) p ((float (*) (float, float)) mult) (2.0f, 3.0f) | |
955 | */ | |
ebc7896c | 956 | prototyped = 1; |
b4b08fa2 TT |
957 | } |
958 | else if (i < TYPE_NFIELDS (ftype)) | |
959 | prototyped = TYPE_PROTOTYPED (ftype); | |
960 | else | |
961 | prototyped = 0; | |
ebc7896c | 962 | |
b4b08fa2 TT |
963 | if (i < TYPE_NFIELDS (ftype)) |
964 | param_type = TYPE_FIELD_TYPE (ftype, i); | |
965 | else | |
966 | param_type = NULL; | |
41f1b697 | 967 | |
b4b08fa2 TT |
968 | args[i] = value_arg_coerce (gdbarch, args[i], |
969 | param_type, prototyped, &sp); | |
ebc7896c | 970 | |
b4b08fa2 TT |
971 | if (param_type != NULL && language_pass_by_reference (param_type)) |
972 | args[i] = value_addr (args[i]); | |
973 | } | |
04714b91 | 974 | |
04714b91 AC |
975 | /* Reserve space for the return structure to be written on the |
976 | stack, if necessary. Make certain that the value is correctly | |
6c659fc2 SC |
977 | aligned. |
978 | ||
979 | While evaluating expressions, we reserve space on the stack for | |
980 | return values of class type even if the language ABI and the target | |
981 | ABI do not require that the return value be passed as a hidden first | |
982 | argument. This is because we want to store the return value as an | |
983 | on-stack temporary while the expression is being evaluated. This | |
984 | enables us to have chained function calls in expressions. | |
04714b91 | 985 | |
6c659fc2 SC |
986 | Keeping the return values as on-stack temporaries while the expression |
987 | is being evaluated is OK because the thread is stopped until the | |
988 | expression is completely evaluated. */ | |
989 | ||
c5ac5cbb | 990 | if (return_method != return_method_normal |
6c659fc2 | 991 | || (stack_temporaries && class_or_union_p (values_type))) |
04714b91 | 992 | { |
0b9dfe2b | 993 | if (gdbarch_inner_than (gdbarch, 1, 2)) |
04714b91 AC |
994 | { |
995 | /* Stack grows downward. Align STRUCT_ADDR and SP after | |
996 | making space for the return value. */ | |
744a8059 | 997 | sp -= TYPE_LENGTH (values_type); |
0b9dfe2b MD |
998 | if (gdbarch_frame_align_p (gdbarch)) |
999 | sp = gdbarch_frame_align (gdbarch, sp); | |
04714b91 AC |
1000 | struct_addr = sp; |
1001 | } | |
1002 | else | |
1003 | { | |
1004 | /* Stack grows upward. Align the frame, allocate space, and | |
1777feb0 | 1005 | then again, re-align the frame??? */ |
0b9dfe2b MD |
1006 | if (gdbarch_frame_align_p (gdbarch)) |
1007 | sp = gdbarch_frame_align (gdbarch, sp); | |
04714b91 | 1008 | struct_addr = sp; |
744a8059 | 1009 | sp += TYPE_LENGTH (values_type); |
0b9dfe2b MD |
1010 | if (gdbarch_frame_align_p (gdbarch)) |
1011 | sp = gdbarch_frame_align (gdbarch, sp); | |
04714b91 AC |
1012 | } |
1013 | } | |
1014 | ||
6ccb583f | 1015 | std::vector<struct value *> new_args; |
c5ac5cbb | 1016 | if (return_method == return_method_hidden_param) |
41f1b697 | 1017 | { |
41f1b697 | 1018 | /* Add the new argument to the front of the argument list. */ |
e71585ff | 1019 | new_args.reserve (args.size ()); |
6ccb583f TT |
1020 | new_args.push_back |
1021 | (value_from_pointer (lookup_pointer_type (values_type), struct_addr)); | |
e71585ff PA |
1022 | new_args.insert (new_args.end (), args.begin (), args.end ()); |
1023 | args = new_args; | |
41f1b697 | 1024 | } |
41f1b697 | 1025 | |
04714b91 AC |
1026 | /* Create the dummy stack frame. Pass in the call dummy address as, |
1027 | presumably, the ABI code knows where, in the call dummy, the | |
1028 | return address should be pointed. */ | |
0b9dfe2b | 1029 | sp = gdbarch_push_dummy_call (gdbarch, function, get_current_regcache (), |
e71585ff PA |
1030 | bp_addr, args.size (), args.data (), |
1031 | sp, return_method, struct_addr); | |
04714b91 | 1032 | |
96860204 AC |
1033 | /* Set up a frame ID for the dummy frame so we can pass it to |
1034 | set_momentary_breakpoint. We need to give the breakpoint a frame | |
1035 | ID so that the breakpoint code can correctly re-identify the | |
1036 | dummy breakpoint. */ | |
8241eaa6 | 1037 | /* Sanity. The exact same SP value is returned by PUSH_DUMMY_CALL, |
669fac23 | 1038 | saved as the dummy-frame TOS, and used by dummy_id to form |
8241eaa6 | 1039 | the frame ID's stack address. */ |
96860204 | 1040 | dummy_id = frame_id_build (sp, bp_addr); |
04714b91 | 1041 | |
74cfe982 AC |
1042 | /* Create a momentary breakpoint at the return address of the |
1043 | inferior. That way it breaks when it returns. */ | |
04714b91 | 1044 | |
74cfe982 | 1045 | { |
51abb421 | 1046 | symtab_and_line sal; |
6c95b8df | 1047 | sal.pspace = current_program_space; |
74cfe982 AC |
1048 | sal.pc = bp_addr; |
1049 | sal.section = find_pc_overlay (sal.pc); | |
51abb421 | 1050 | |
8241eaa6 AC |
1051 | /* Sanity. The exact same SP value is returned by |
1052 | PUSH_DUMMY_CALL, saved as the dummy-frame TOS, and used by | |
669fac23 | 1053 | dummy_id to form the frame ID's stack address. */ |
454dafbd TT |
1054 | breakpoint *bpt |
1055 | = set_momentary_breakpoint (gdbarch, sal, | |
1056 | dummy_id, bp_call_dummy).release (); | |
c70a6932 JK |
1057 | |
1058 | /* set_momentary_breakpoint invalidates FRAME. */ | |
1059 | frame = NULL; | |
1060 | ||
74cfe982 | 1061 | bpt->disposition = disp_del; |
e2e4d78b JK |
1062 | gdb_assert (bpt->related_breakpoint == bpt); |
1063 | ||
51abb421 | 1064 | breakpoint *longjmp_b = set_longjmp_breakpoint_for_call_dummy (); |
e2e4d78b JK |
1065 | if (longjmp_b) |
1066 | { | |
1067 | /* Link BPT into the chain of LONGJMP_B. */ | |
1068 | bpt->related_breakpoint = longjmp_b; | |
1069 | while (longjmp_b->related_breakpoint != bpt->related_breakpoint) | |
1070 | longjmp_b = longjmp_b->related_breakpoint; | |
1071 | longjmp_b->related_breakpoint = bpt; | |
1072 | } | |
74cfe982 | 1073 | } |
04714b91 | 1074 | |
7cd1089b PM |
1075 | /* Create a breakpoint in std::terminate. |
1076 | If a C++ exception is raised in the dummy-frame, and the | |
1077 | exception handler is (normally, and expected to be) out-of-frame, | |
1078 | the default C++ handler will (wrongly) be called in an inferior | |
1079 | function call. This is wrong, as an exception can be normally | |
1080 | and legally handled out-of-frame. The confines of the dummy frame | |
1081 | prevent the unwinder from finding the correct handler (or any | |
1082 | handler, unless it is in-frame). The default handler calls | |
1083 | std::terminate. This will kill the inferior. Assert that | |
1084 | terminate should never be called in an inferior function | |
1085 | call. Place a momentary breakpoint in the std::terminate function | |
1086 | and if triggered in the call, rewind. */ | |
1087 | if (unwind_on_terminating_exception_p) | |
aa7d318d | 1088 | set_std_terminate_breakpoint (); |
7cd1089b | 1089 | |
96860204 AC |
1090 | /* Everything's ready, push all the info needed to restore the |
1091 | caller (and identify the dummy-frame) onto the dummy-frame | |
1092 | stack. */ | |
c7c4d3fa | 1093 | dummy_frame_push (caller_state.release (), &dummy_id, call_thread.get ()); |
ed12ef62 | 1094 | if (dummy_dtor != NULL) |
00431a78 | 1095 | register_dummy_frame_dtor (dummy_id, call_thread.get (), |
ed12ef62 | 1096 | dummy_dtor, dummy_dtor_data); |
b89667eb | 1097 | |
7cd1089b | 1098 | /* Register a clean-up for unwind_on_terminating_exception_breakpoint. */ |
2cc83d1e | 1099 | SCOPE_EXIT { delete_std_terminate_breakpoint (); }; |
7cd1089b | 1100 | |
96860204 AC |
1101 | /* - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - |
1102 | If you're looking to implement asynchronous dummy-frames, then | |
1103 | just below is the place to chop this function in two.. */ | |
1104 | ||
74cfe982 | 1105 | { |
388a7084 PA |
1106 | struct thread_fsm *saved_sm; |
1107 | struct call_thread_fsm *sm; | |
1108 | ||
1109 | /* Save the current FSM. We'll override it. */ | |
00431a78 PA |
1110 | saved_sm = call_thread->thread_fsm; |
1111 | call_thread->thread_fsm = NULL; | |
74cfe982 | 1112 | |
b89667eb DE |
1113 | /* Save this thread's ptid, we need it later but the thread |
1114 | may have exited. */ | |
00431a78 | 1115 | call_thread_ptid = call_thread->ptid; |
74cfe982 | 1116 | |
b89667eb | 1117 | /* Run the inferior until it stops. */ |
f5871ec0 | 1118 | |
388a7084 PA |
1119 | /* Create the FSM used to manage the infcall. It tells infrun to |
1120 | not report the stop to the user, and captures the return value | |
1121 | before the dummy frame is popped. run_inferior_call registers | |
1122 | it with the thread ASAP. */ | |
46e3ed7f | 1123 | sm = new call_thread_fsm (current_ui, command_interp (), |
3b12939d | 1124 | gdbarch, function, |
388a7084 | 1125 | values_type, |
c5ac5cbb | 1126 | return_method != return_method_normal, |
388a7084 PA |
1127 | struct_addr); |
1128 | ||
00431a78 | 1129 | e = run_inferior_call (sm, call_thread.get (), real_pc); |
388a7084 | 1130 | |
76727919 | 1131 | gdb::observers::inferior_call_post.notify (call_thread_ptid, funaddr); |
388a7084 | 1132 | |
00431a78 | 1133 | if (call_thread->state != THREAD_EXITED) |
388a7084 PA |
1134 | { |
1135 | /* The FSM should still be the same. */ | |
46e3ed7f | 1136 | gdb_assert (call_thread->thread_fsm == sm); |
388a7084 | 1137 | |
46e3ed7f | 1138 | if (call_thread->thread_fsm->finished_p ()) |
388a7084 PA |
1139 | { |
1140 | struct value *retval; | |
1141 | ||
1142 | /* The inferior call is successful. Pop the dummy frame, | |
1143 | which runs its destructors and restores the inferior's | |
1144 | suspend state, and restore the inferior control | |
1145 | state. */ | |
00431a78 | 1146 | dummy_frame_pop (dummy_id, call_thread.get ()); |
c7c4d3fa | 1147 | restore_infcall_control_state (inf_status.release ()); |
388a7084 PA |
1148 | |
1149 | /* Get the return value. */ | |
1150 | retval = sm->return_value; | |
1151 | ||
1152 | /* Clean up / destroy the call FSM, and restore the | |
1153 | original one. */ | |
46e3ed7f TT |
1154 | call_thread->thread_fsm->clean_up (call_thread.get ()); |
1155 | delete call_thread->thread_fsm; | |
00431a78 | 1156 | call_thread->thread_fsm = saved_sm; |
04714b91 | 1157 | |
388a7084 PA |
1158 | maybe_remove_breakpoints (); |
1159 | ||
388a7084 PA |
1160 | gdb_assert (retval != NULL); |
1161 | return retval; | |
1162 | } | |
1163 | ||
e3319240 PW |
1164 | /* Didn't complete. Clean up / destroy the call FSM, and restore the |
1165 | previous state machine, and handle the error. */ | |
46e3ed7f TT |
1166 | call_thread->thread_fsm->clean_up (call_thread.get ()); |
1167 | delete call_thread->thread_fsm; | |
00431a78 | 1168 | call_thread->thread_fsm = saved_sm; |
388a7084 PA |
1169 | } |
1170 | } | |
162078c8 | 1171 | |
b89667eb DE |
1172 | /* Rethrow an error if we got one trying to run the inferior. */ |
1173 | ||
1174 | if (e.reason < 0) | |
1175 | { | |
1176 | const char *name = get_function_name (funaddr, | |
1177 | name_buf, sizeof (name_buf)); | |
1178 | ||
c7c4d3fa | 1179 | discard_infcall_control_state (inf_status.release ()); |
b89667eb DE |
1180 | |
1181 | /* We could discard the dummy frame here if the program exited, | |
1182 | but it will get garbage collected the next time the program is | |
1183 | run anyway. */ | |
1184 | ||
1185 | switch (e.reason) | |
1186 | { | |
1187 | case RETURN_ERROR: | |
ac74f770 MS |
1188 | throw_error (e.error, _("%s\n\ |
1189 | An error occurred while in a function called from GDB.\n\ | |
1190 | Evaluation of the expression containing the function\n\ | |
1191 | (%s) will be abandoned.\n\ | |
1192 | When the function is done executing, GDB will silently stop."), | |
b89667eb DE |
1193 | e.message, name); |
1194 | case RETURN_QUIT: | |
1195 | default: | |
1196 | throw_exception (e); | |
1197 | } | |
1198 | } | |
1199 | ||
1200 | /* If the program has exited, or we stopped at a different thread, | |
1201 | exit and inform the user. */ | |
1202 | ||
de04a248 DE |
1203 | if (! target_has_execution) |
1204 | { | |
b89667eb DE |
1205 | const char *name = get_function_name (funaddr, |
1206 | name_buf, sizeof (name_buf)); | |
1207 | ||
1208 | /* If we try to restore the inferior status, | |
de04a248 | 1209 | we'll crash as the inferior is no longer running. */ |
c7c4d3fa | 1210 | discard_infcall_control_state (inf_status.release ()); |
b89667eb DE |
1211 | |
1212 | /* We could discard the dummy frame here given that the program exited, | |
1213 | but it will get garbage collected the next time the program is | |
1214 | run anyway. */ | |
1215 | ||
3e43a32a MS |
1216 | error (_("The program being debugged exited while in a function " |
1217 | "called from GDB.\n" | |
1218 | "Evaluation of the expression containing the function\n" | |
1219 | "(%s) will be abandoned."), | |
b89667eb DE |
1220 | name); |
1221 | } | |
1222 | ||
d7e15655 | 1223 | if (call_thread_ptid != inferior_ptid) |
b89667eb DE |
1224 | { |
1225 | const char *name = get_function_name (funaddr, | |
1226 | name_buf, sizeof (name_buf)); | |
1227 | ||
1228 | /* We've switched threads. This can happen if another thread gets a | |
1229 | signal or breakpoint while our thread was running. | |
1230 | There's no point in restoring the inferior status, | |
1231 | we're in a different thread. */ | |
c7c4d3fa | 1232 | discard_infcall_control_state (inf_status.release ()); |
b89667eb DE |
1233 | /* Keep the dummy frame record, if the user switches back to the |
1234 | thread with the hand-call, we'll need it. */ | |
1235 | if (stopped_by_random_signal) | |
ac74f770 MS |
1236 | error (_("\ |
1237 | The program received a signal in another thread while\n\ | |
1238 | making a function call from GDB.\n\ | |
1239 | Evaluation of the expression containing the function\n\ | |
1240 | (%s) will be abandoned.\n\ | |
1241 | When the function is done executing, GDB will silently stop."), | |
b89667eb DE |
1242 | name); |
1243 | else | |
ac74f770 MS |
1244 | error (_("\ |
1245 | The program stopped in another thread while making a function call from GDB.\n\ | |
1246 | Evaluation of the expression containing the function\n\ | |
1247 | (%s) will be abandoned.\n\ | |
1248 | When the function is done executing, GDB will silently stop."), | |
b89667eb | 1249 | name); |
de04a248 DE |
1250 | } |
1251 | ||
52557533 | 1252 | { |
5fe75eec | 1253 | /* Make a copy as NAME may be in an objfile freed by dummy_frame_pop. */ |
395423c4 TT |
1254 | std::string name = get_function_name (funaddr, name_buf, |
1255 | sizeof (name_buf)); | |
b89667eb | 1256 | |
52557533 AC |
1257 | if (stopped_by_random_signal) |
1258 | { | |
1259 | /* We stopped inside the FUNCTION because of a random | |
1260 | signal. Further execution of the FUNCTION is not | |
1777feb0 | 1261 | allowed. */ |
04714b91 | 1262 | |
52557533 AC |
1263 | if (unwind_on_signal_p) |
1264 | { | |
1777feb0 | 1265 | /* The user wants the context restored. */ |
52557533 AC |
1266 | |
1267 | /* We must get back to the frame we were before the | |
b89667eb | 1268 | dummy call. */ |
00431a78 | 1269 | dummy_frame_pop (dummy_id, call_thread.get ()); |
b89667eb DE |
1270 | |
1271 | /* We also need to restore inferior status to that before the | |
1272 | dummy call. */ | |
c7c4d3fa | 1273 | restore_infcall_control_state (inf_status.release ()); |
04714b91 | 1274 | |
52557533 AC |
1275 | /* FIXME: Insert a bunch of wrap_here; name can be very |
1276 | long if it's a C++ name with arguments and stuff. */ | |
ac74f770 MS |
1277 | error (_("\ |
1278 | The program being debugged was signaled while in a function called from GDB.\n\ | |
1279 | GDB has restored the context to what it was before the call.\n\ | |
1280 | To change this behavior use \"set unwindonsignal off\".\n\ | |
1281 | Evaluation of the expression containing the function\n\ | |
1282 | (%s) will be abandoned."), | |
395423c4 | 1283 | name.c_str ()); |
52557533 AC |
1284 | } |
1285 | else | |
1286 | { | |
1287 | /* The user wants to stay in the frame where we stopped | |
b89667eb DE |
1288 | (default). |
1289 | Discard inferior status, we're not at the same point | |
1290 | we started at. */ | |
c7c4d3fa | 1291 | discard_infcall_control_state (inf_status.release ()); |
b89667eb | 1292 | |
52557533 AC |
1293 | /* FIXME: Insert a bunch of wrap_here; name can be very |
1294 | long if it's a C++ name with arguments and stuff. */ | |
ac74f770 MS |
1295 | error (_("\ |
1296 | The program being debugged was signaled while in a function called from GDB.\n\ | |
1297 | GDB remains in the frame where the signal was received.\n\ | |
1298 | To change this behavior use \"set unwindonsignal on\".\n\ | |
1299 | Evaluation of the expression containing the function\n\ | |
1300 | (%s) will be abandoned.\n\ | |
1301 | When the function is done executing, GDB will silently stop."), | |
395423c4 | 1302 | name.c_str ()); |
52557533 AC |
1303 | } |
1304 | } | |
04714b91 | 1305 | |
aa7d318d | 1306 | if (stop_stack_dummy == STOP_STD_TERMINATE) |
52557533 | 1307 | { |
aa7d318d TT |
1308 | /* We must get back to the frame we were before the dummy |
1309 | call. */ | |
00431a78 | 1310 | dummy_frame_pop (dummy_id, call_thread.get ()); |
7cd1089b | 1311 | |
aa7d318d TT |
1312 | /* We also need to restore inferior status to that before |
1313 | the dummy call. */ | |
c7c4d3fa | 1314 | restore_infcall_control_state (inf_status.release ()); |
aa7d318d | 1315 | |
ac74f770 MS |
1316 | error (_("\ |
1317 | The program being debugged entered a std::terminate call, most likely\n\ | |
1318 | caused by an unhandled C++ exception. GDB blocked this call in order\n\ | |
1319 | to prevent the program from being terminated, and has restored the\n\ | |
1320 | context to its original state before the call.\n\ | |
1321 | To change this behaviour use \"set unwind-on-terminating-exception off\".\n\ | |
1322 | Evaluation of the expression containing the function (%s)\n\ | |
1323 | will be abandoned."), | |
395423c4 | 1324 | name.c_str ()); |
aa7d318d TT |
1325 | } |
1326 | else if (stop_stack_dummy == STOP_NONE) | |
1327 | { | |
1328 | ||
b89667eb DE |
1329 | /* We hit a breakpoint inside the FUNCTION. |
1330 | Keep the dummy frame, the user may want to examine its state. | |
1331 | Discard inferior status, we're not at the same point | |
1332 | we started at. */ | |
c7c4d3fa | 1333 | discard_infcall_control_state (inf_status.release ()); |
b89667eb | 1334 | |
52557533 AC |
1335 | /* The following error message used to say "The expression |
1336 | which contained the function call has been discarded." | |
1337 | It is a hard concept to explain in a few words. Ideally, | |
1338 | GDB would be able to resume evaluation of the expression | |
1339 | when the function finally is done executing. Perhaps | |
1340 | someday this will be implemented (it would not be easy). */ | |
1341 | /* FIXME: Insert a bunch of wrap_here; name can be very long if it's | |
1342 | a C++ name with arguments and stuff. */ | |
ac74f770 MS |
1343 | error (_("\ |
1344 | The program being debugged stopped while in a function called from GDB.\n\ | |
1345 | Evaluation of the expression containing the function\n\ | |
1346 | (%s) will be abandoned.\n\ | |
1347 | When the function is done executing, GDB will silently stop."), | |
395423c4 | 1348 | name.c_str ()); |
52557533 AC |
1349 | } |
1350 | ||
52557533 | 1351 | } |
04714b91 | 1352 | |
388a7084 PA |
1353 | /* The above code errors out, so ... */ |
1354 | gdb_assert_not_reached ("... should not be here"); | |
04714b91 | 1355 | } |
04714b91 AC |
1356 | |
1357 | void | |
1358 | _initialize_infcall (void) | |
1359 | { | |
1360 | add_setshow_boolean_cmd ("coerce-float-to-double", class_obscure, | |
7915a72c AC |
1361 | &coerce_float_to_double_p, _("\ |
1362 | Set coercion of floats to doubles when calling functions."), _("\ | |
1363 | Show coercion of floats to doubles when calling functions"), _("\ | |
04714b91 AC |
1364 | Variables of type float should generally be converted to doubles before\n\ |
1365 | calling an unprototyped function, and left alone when calling a prototyped\n\ | |
1366 | function. However, some older debug info formats do not provide enough\n\ | |
1367 | information to determine that a function is prototyped. If this flag is\n\ | |
1368 | set, GDB will perform the conversion for a function it considers\n\ | |
1369 | unprototyped.\n\ | |
7915a72c | 1370 | The default is to perform the conversion.\n"), |
2c5b56ce | 1371 | NULL, |
920d2a44 | 1372 | show_coerce_float_to_double_p, |
2c5b56ce | 1373 | &setlist, &showlist); |
04714b91 AC |
1374 | |
1375 | add_setshow_boolean_cmd ("unwindonsignal", no_class, | |
7915a72c AC |
1376 | &unwind_on_signal_p, _("\ |
1377 | Set unwinding of stack if a signal is received while in a call dummy."), _("\ | |
1378 | Show unwinding of stack if a signal is received while in a call dummy."), _("\ | |
04714b91 AC |
1379 | The unwindonsignal lets the user determine what gdb should do if a signal\n\ |
1380 | is received while in a function called from gdb (call dummy). If set, gdb\n\ | |
1381 | unwinds the stack and restore the context to what as it was before the call.\n\ | |
7915a72c | 1382 | The default is to stop in the frame where the signal was received."), |
2c5b56ce | 1383 | NULL, |
920d2a44 | 1384 | show_unwind_on_signal_p, |
2c5b56ce | 1385 | &setlist, &showlist); |
7cd1089b PM |
1386 | |
1387 | add_setshow_boolean_cmd ("unwind-on-terminating-exception", no_class, | |
1388 | &unwind_on_terminating_exception_p, _("\ | |
1389 | Set unwinding of stack if std::terminate is called while in call dummy."), _("\ | |
3e43a32a MS |
1390 | Show unwinding of stack if std::terminate() is called while in a call dummy."), |
1391 | _("\ | |
7cd1089b PM |
1392 | The unwind on terminating exception flag lets the user determine\n\ |
1393 | what gdb should do if a std::terminate() call is made from the\n\ | |
1394 | default exception handler. If set, gdb unwinds the stack and restores\n\ | |
1395 | the context to what it was before the call. If unset, gdb allows the\n\ | |
1396 | std::terminate call to proceed.\n\ | |
1397 | The default is to unwind the frame."), | |
1398 | NULL, | |
1399 | show_unwind_on_terminating_exception_p, | |
1400 | &setlist, &showlist); | |
1401 | ||
04714b91 | 1402 | } |