File: | src/gnu/usr.bin/binutils/gdb/infcall.c |
Warning: | line 441, column 4 Value stored to 'dummy_addr' is never read |
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1 | /* Perform an inferior function call, for GDB, the GNU debugger. |
2 | |
3 | Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, |
4 | 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 |
5 | Free Software Foundation, Inc. |
6 | |
7 | This file is part of GDB. |
8 | |
9 | This program is free software; you can redistribute it and/or modify |
10 | it under the terms of the GNU General Public License as published by |
11 | the Free Software Foundation; either version 2 of the License, or |
12 | (at your option) any later version. |
13 | |
14 | This program is distributed in the hope that it will be useful, |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
17 | GNU General Public License for more details. |
18 | |
19 | You should have received a copy of the GNU General Public License |
20 | along with this program; if not, write to the Free Software |
21 | Foundation, Inc., 59 Temple Place - Suite 330, |
22 | Boston, MA 02111-1307, USA. */ |
23 | |
24 | #include "defs.h" |
25 | #include "breakpoint.h" |
26 | #include "target.h" |
27 | #include "regcache.h" |
28 | #include "inferior.h" |
29 | #include "gdb_assert.h" |
30 | #include "block.h" |
31 | #include "gdbcore.h" |
32 | #include "language.h" |
33 | #include "objfiles.h" |
34 | #include "gdbcmd.h" |
35 | #include "command.h" |
36 | #include "gdb_string.h" |
37 | #include "infcall.h" |
38 | #include "dummy-frame.h" |
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; |
68 | |
69 | /* This boolean tells what gdb should do if a signal is received while |
70 | in a function called from gdb (call dummy). If set, gdb unwinds |
71 | the stack and restore the context to what as it was before the |
72 | call. |
73 | |
74 | The default is to stop in the frame where the signal was received. */ |
75 | |
76 | int unwind_on_signal_p = 0; |
77 | |
78 | /* Perform the standard coercions that are specified |
79 | for arguments to be passed to C functions. |
80 | |
81 | If PARAM_TYPE is non-NULL, it is the expected parameter type. |
82 | IS_PROTOTYPED is non-zero if the function declaration is prototyped. */ |
83 | |
84 | static struct value * |
85 | value_arg_coerce (struct value *arg, struct type *param_type, |
86 | int is_prototyped) |
87 | { |
88 | struct type *arg_type = check_typedef (VALUE_TYPE (arg)(arg)->type); |
89 | struct type *type |
90 | = param_type ? check_typedef (param_type) : arg_type; |
91 | |
92 | switch (TYPE_CODE (type)(type)->main_type->code) |
93 | { |
94 | case TYPE_CODE_REF: |
95 | if (TYPE_CODE (arg_type)(arg_type)->main_type->code != TYPE_CODE_REF |
96 | && TYPE_CODE (arg_type)(arg_type)->main_type->code != TYPE_CODE_PTR) |
97 | { |
98 | arg = value_addr (arg); |
99 | VALUE_TYPE (arg)(arg)->type = param_type; |
100 | return arg; |
101 | } |
102 | break; |
103 | case TYPE_CODE_INT: |
104 | case TYPE_CODE_CHAR: |
105 | case TYPE_CODE_BOOL: |
106 | case TYPE_CODE_ENUM: |
107 | /* If we don't have a prototype, coerce to integer type if necessary. */ |
108 | if (!is_prototyped) |
109 | { |
110 | if (TYPE_LENGTH (type)(type)->length < TYPE_LENGTH (builtin_type_int)(builtin_type_int)->length) |
111 | type = builtin_type_int; |
112 | } |
113 | /* Currently all target ABIs require at least the width of an integer |
114 | type for an argument. We may have to conditionalize the following |
115 | type coercion for future targets. */ |
116 | if (TYPE_LENGTH (type)(type)->length < TYPE_LENGTH (builtin_type_int)(builtin_type_int)->length) |
117 | type = builtin_type_int; |
118 | break; |
119 | case TYPE_CODE_FLT: |
120 | if (!is_prototyped && coerce_float_to_double_p) |
121 | { |
122 | if (TYPE_LENGTH (type)(type)->length < TYPE_LENGTH (builtin_type_double)(builtin_type_double)->length) |
123 | type = builtin_type_double; |
124 | else if (TYPE_LENGTH (type)(type)->length > TYPE_LENGTH (builtin_type_double)(builtin_type_double)->length) |
125 | type = builtin_type_long_double; |
126 | } |
127 | break; |
128 | case TYPE_CODE_FUNC: |
129 | type = lookup_pointer_type (type); |
130 | break; |
131 | case TYPE_CODE_ARRAY: |
132 | /* Arrays are coerced to pointers to their first element, unless |
133 | they are vectors, in which case we want to leave them alone, |
134 | because they are passed by value. */ |
135 | if (current_language->c_style_arrays) |
136 | if (!TYPE_VECTOR (type)((type)->main_type->flags & (1 << 12))) |
137 | type = lookup_pointer_type (TYPE_TARGET_TYPE (type)(type)->main_type->target_type); |
138 | break; |
139 | case TYPE_CODE_UNDEF: |
140 | case TYPE_CODE_PTR: |
141 | case TYPE_CODE_STRUCT: |
142 | case TYPE_CODE_UNION: |
143 | case TYPE_CODE_VOID: |
144 | case TYPE_CODE_SET: |
145 | case TYPE_CODE_RANGE: |
146 | case TYPE_CODE_STRING: |
147 | case TYPE_CODE_BITSTRING: |
148 | case TYPE_CODE_ERROR: |
149 | case TYPE_CODE_MEMBER: |
150 | case TYPE_CODE_METHOD: |
151 | case TYPE_CODE_COMPLEX: |
152 | default: |
153 | break; |
154 | } |
155 | |
156 | return value_cast (type, arg); |
157 | } |
158 | |
159 | /* Determine a function's address and its return type from its value. |
160 | Calls error() if the function is not valid for calling. */ |
161 | |
162 | CORE_ADDR |
163 | find_function_addr (struct value *function, struct type **retval_type) |
164 | { |
165 | struct type *ftype = check_typedef (VALUE_TYPE (function)(function)->type); |
166 | enum type_code code = TYPE_CODE (ftype)(ftype)->main_type->code; |
167 | struct type *value_type; |
168 | CORE_ADDR funaddr; |
169 | |
170 | /* If it's a member function, just look at the function |
171 | part of it. */ |
172 | |
173 | /* Determine address to call. */ |
174 | if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD) |
175 | { |
176 | funaddr = VALUE_ADDRESS (function)(function)->location.address; |
177 | value_type = TYPE_TARGET_TYPE (ftype)(ftype)->main_type->target_type; |
178 | } |
179 | else if (code == TYPE_CODE_PTR) |
180 | { |
181 | funaddr = value_as_address (function); |
182 | ftype = check_typedef (TYPE_TARGET_TYPE (ftype)(ftype)->main_type->target_type); |
183 | if (TYPE_CODE (ftype)(ftype)->main_type->code == TYPE_CODE_FUNC |
184 | || TYPE_CODE (ftype)(ftype)->main_type->code == TYPE_CODE_METHOD) |
185 | { |
186 | funaddr = gdbarch_convert_from_func_ptr_addr (current_gdbarch, |
187 | funaddr, |
188 | ¤t_target); |
189 | value_type = TYPE_TARGET_TYPE (ftype)(ftype)->main_type->target_type; |
190 | } |
191 | else |
192 | value_type = builtin_type_int; |
193 | } |
194 | else if (code == TYPE_CODE_INT) |
195 | { |
196 | /* Handle the case of functions lacking debugging info. |
197 | Their values are characters since their addresses are char */ |
198 | if (TYPE_LENGTH (ftype)(ftype)->length == 1) |
199 | funaddr = value_as_address (value_addr (function)); |
200 | else |
201 | /* Handle integer used as address of a function. */ |
202 | funaddr = (CORE_ADDR) value_as_long (function); |
203 | |
204 | value_type = builtin_type_int; |
205 | } |
206 | else |
207 | error ("Invalid data type for function to be called."); |
208 | |
209 | if (retval_type != NULL((void*)0)) |
210 | *retval_type = value_type; |
211 | return funaddr + DEPRECATED_FUNCTION_START_OFFSET(gdbarch_deprecated_function_start_offset (current_gdbarch)); |
212 | } |
213 | |
214 | /* Call breakpoint_auto_delete on the current contents of the bpstat |
215 | pointed to by arg (which is really a bpstat *). */ |
216 | |
217 | static void |
218 | breakpoint_auto_delete_contents (void *arg) |
219 | { |
220 | breakpoint_auto_delete (*(bpstat *) arg); |
221 | } |
222 | |
223 | static CORE_ADDR |
224 | generic_push_dummy_code (struct gdbarch *gdbarch, |
225 | CORE_ADDR sp, CORE_ADDR funaddr, int using_gcc, |
226 | struct value **args, int nargs, |
227 | struct type *value_type, |
228 | CORE_ADDR *real_pc, CORE_ADDR *bp_addr) |
229 | { |
230 | /* Something here to findout the size of a breakpoint and then |
231 | allocate space for it on the stack. */ |
232 | int bplen; |
233 | /* This code assumes frame align. */ |
234 | gdb_assert (gdbarch_frame_align_p (gdbarch))((void) ((gdbarch_frame_align_p (gdbarch)) ? 0 : (internal_error ("/usr/src/gnu/usr.bin/binutils/gdb/infcall.c", 234, "%s: Assertion `%s' failed." , __PRETTY_FUNCTION__, "gdbarch_frame_align_p (gdbarch)"), 0) )); |
235 | /* Force the stack's alignment. The intent is to ensure that the SP |
236 | is aligned to at least a breakpoint instruction's boundary. */ |
237 | sp = gdbarch_frame_align (gdbarch, sp); |
238 | /* Allocate space for, and then position the breakpoint on the |
239 | stack. */ |
240 | if (gdbarch_inner_than (gdbarch, 1, 2)) |
241 | { |
242 | CORE_ADDR bppc = sp; |
243 | gdbarch_breakpoint_from_pc (gdbarch, &bppc, &bplen); |
244 | sp = gdbarch_frame_align (gdbarch, sp - bplen); |
245 | (*bp_addr) = sp; |
246 | /* Should the breakpoint size/location be re-computed here? */ |
247 | } |
248 | else |
249 | { |
250 | (*bp_addr) = sp; |
251 | gdbarch_breakpoint_from_pc (gdbarch, bp_addr, &bplen); |
252 | sp = gdbarch_frame_align (gdbarch, sp + bplen); |
253 | } |
254 | /* Inferior resumes at the function entry point. */ |
255 | (*real_pc) = funaddr; |
256 | return sp; |
257 | } |
258 | |
259 | /* For CALL_DUMMY_ON_STACK, push a breakpoint sequence that the called |
260 | function returns to. */ |
261 | |
262 | static CORE_ADDR |
263 | push_dummy_code (struct gdbarch *gdbarch, |
264 | CORE_ADDR sp, CORE_ADDR funaddr, int using_gcc, |
265 | struct value **args, int nargs, |
266 | struct type *value_type, |
267 | CORE_ADDR *real_pc, CORE_ADDR *bp_addr) |
268 | { |
269 | if (gdbarch_push_dummy_code_p (gdbarch)) |
270 | return gdbarch_push_dummy_code (gdbarch, sp, funaddr, using_gcc, |
271 | args, nargs, value_type, real_pc, bp_addr); |
272 | else |
273 | return generic_push_dummy_code (gdbarch, sp, funaddr, using_gcc, |
274 | args, nargs, value_type, real_pc, bp_addr); |
275 | } |
276 | |
277 | /* All this stuff with a dummy frame may seem unnecessarily complicated |
278 | (why not just save registers in GDB?). The purpose of pushing a dummy |
279 | frame which looks just like a real frame is so that if you call a |
280 | function and then hit a breakpoint (get a signal, etc), "backtrace" |
281 | will look right. Whether the backtrace needs to actually show the |
282 | stack at the time the inferior function was called is debatable, but |
283 | it certainly needs to not display garbage. So if you are contemplating |
284 | making dummy frames be different from normal frames, consider that. */ |
285 | |
286 | /* Perform a function call in the inferior. |
287 | ARGS is a vector of values of arguments (NARGS of them). |
288 | FUNCTION is a value, the function to be called. |
289 | Returns a value representing what the function returned. |
290 | May fail to return, if a breakpoint or signal is hit |
291 | during the execution of the function. |
292 | |
293 | ARGS is modified to contain coerced values. */ |
294 | |
295 | struct value * |
296 | call_function_by_hand (struct value *function, int nargs, struct value **args) |
297 | { |
298 | CORE_ADDR sp; |
299 | CORE_ADDR dummy_addr; |
300 | struct type *value_type; |
301 | unsigned char struct_return; |
302 | CORE_ADDR struct_addr = 0; |
303 | struct regcache *retbuf; |
304 | struct cleanup *retbuf_cleanup; |
305 | struct inferior_status *inf_status; |
306 | struct cleanup *inf_status_cleanup; |
307 | CORE_ADDR funaddr; |
308 | int using_gcc; /* Set to version of gcc in use, or zero if not gcc */ |
309 | CORE_ADDR real_pc; |
310 | struct type *ftype = check_typedef (VALUE_TYPE (function)(function)->type); |
311 | CORE_ADDR bp_addr; |
312 | struct regcache *caller_regcache; |
313 | struct cleanup *caller_regcache_cleanup; |
314 | struct frame_id dummy_id; |
315 | |
316 | if (!target_has_execution(current_target.to_has_execution)) |
317 | noprocess (); |
318 | |
319 | /* Create a cleanup chain that contains the retbuf (buffer |
320 | containing the register values). This chain is create BEFORE the |
321 | inf_status chain so that the inferior status can cleaned up |
322 | (restored or discarded) without having the retbuf freed. */ |
323 | retbuf = regcache_xmalloc (current_gdbarch); |
324 | retbuf_cleanup = make_cleanup_regcache_xfree (retbuf); |
325 | |
326 | /* A cleanup for the inferior status. Create this AFTER the retbuf |
327 | so that this can be discarded or applied without interfering with |
328 | the regbuf. */ |
329 | inf_status = save_inferior_status (1); |
330 | inf_status_cleanup = make_cleanup_restore_inferior_status (inf_status); |
331 | |
332 | /* Save the caller's registers so that they can be restored once the |
333 | callee returns. To allow nested calls the registers are (further |
334 | down) pushed onto a dummy frame stack. Include a cleanup (which |
335 | is tossed once the regcache has been pushed). */ |
336 | caller_regcache = frame_save_as_regcache (get_current_frame ()); |
337 | caller_regcache_cleanup = make_cleanup_regcache_xfree (caller_regcache); |
338 | |
339 | /* Ensure that the initial SP is correctly aligned. */ |
340 | { |
341 | CORE_ADDR old_sp = read_sp (); |
342 | if (gdbarch_frame_align_p (current_gdbarch)) |
343 | { |
344 | sp = gdbarch_frame_align (current_gdbarch, old_sp); |
345 | /* NOTE: cagney/2003-08-13: Skip the "red zone". For some |
346 | ABIs, a function can use memory beyond the inner most stack |
347 | address. AMD64 called that region the "red zone". Skip at |
348 | least the "red zone" size before allocating any space on |
349 | the stack. */ |
350 | if (INNER_THAN (1, 2)(gdbarch_inner_than (current_gdbarch, 1, 2))) |
351 | sp -= gdbarch_frame_red_zone_size (current_gdbarch); |
352 | else |
353 | sp += gdbarch_frame_red_zone_size (current_gdbarch); |
354 | /* Still aligned? */ |
355 | gdb_assert (sp == gdbarch_frame_align (current_gdbarch, sp))((void) ((sp == gdbarch_frame_align (current_gdbarch, sp)) ? 0 : (internal_error ("/usr/src/gnu/usr.bin/binutils/gdb/infcall.c" , 355, "%s: Assertion `%s' failed.", __PRETTY_FUNCTION__, "sp == gdbarch_frame_align (current_gdbarch, sp)" ), 0))); |
356 | /* NOTE: cagney/2002-09-18: |
357 | |
358 | On a RISC architecture, a void parameterless generic dummy |
359 | frame (i.e., no parameters, no result) typically does not |
360 | need to push anything the stack and hence can leave SP and |
361 | FP. Similarly, a frameless (possibly leaf) function does |
362 | not push anything on the stack and, hence, that too can |
363 | leave FP and SP unchanged. As a consequence, a sequence of |
364 | void parameterless generic dummy frame calls to frameless |
365 | functions will create a sequence of effectively identical |
366 | frames (SP, FP and TOS and PC the same). This, not |
367 | suprisingly, results in what appears to be a stack in an |
368 | infinite loop --- when GDB tries to find a generic dummy |
369 | frame on the internal dummy frame stack, it will always |
370 | find the first one. |
371 | |
372 | To avoid this problem, the code below always grows the |
373 | stack. That way, two dummy frames can never be identical. |
374 | It does burn a few bytes of stack but that is a small price |
375 | to pay :-). */ |
376 | if (sp == old_sp) |
377 | { |
378 | if (INNER_THAN (1, 2)(gdbarch_inner_than (current_gdbarch, 1, 2))) |
379 | /* Stack grows down. */ |
380 | sp = gdbarch_frame_align (current_gdbarch, old_sp - 1); |
381 | else |
382 | /* Stack grows up. */ |
383 | sp = gdbarch_frame_align (current_gdbarch, old_sp + 1); |
384 | } |
385 | gdb_assert ((INNER_THAN (1, 2) && sp <= old_sp)((void) ((((gdbarch_inner_than (current_gdbarch, 1, 2)) && sp <= old_sp) || ((gdbarch_inner_than (current_gdbarch, 2 , 1)) && sp >= old_sp)) ? 0 : (internal_error ("/usr/src/gnu/usr.bin/binutils/gdb/infcall.c" , 386, "%s: Assertion `%s' failed.", __PRETTY_FUNCTION__, "(INNER_THAN (1, 2) && sp <= old_sp) || (INNER_THAN (2, 1) && sp >= old_sp)" ), 0))) |
386 | || (INNER_THAN (2, 1) && sp >= old_sp))((void) ((((gdbarch_inner_than (current_gdbarch, 1, 2)) && sp <= old_sp) || ((gdbarch_inner_than (current_gdbarch, 2 , 1)) && sp >= old_sp)) ? 0 : (internal_error ("/usr/src/gnu/usr.bin/binutils/gdb/infcall.c" , 386, "%s: Assertion `%s' failed.", __PRETTY_FUNCTION__, "(INNER_THAN (1, 2) && sp <= old_sp) || (INNER_THAN (2, 1) && sp >= old_sp)" ), 0))); |
387 | } |
388 | else |
389 | /* FIXME: cagney/2002-09-18: Hey, you loose! |
390 | |
391 | Who knows how badly aligned the SP is! |
392 | |
393 | If the generic dummy frame ends up empty (because nothing is |
394 | pushed) GDB won't be able to correctly perform back traces. |
395 | If a target is having trouble with backtraces, first thing to |
396 | do is add FRAME_ALIGN() to the architecture vector. If that |
397 | fails, try unwind_dummy_id(). |
398 | |
399 | If the ABI specifies a "Red Zone" (see the doco) the code |
400 | below will quietly trash it. */ |
401 | sp = old_sp; |
402 | } |
403 | |
404 | funaddr = find_function_addr (function, &value_type); |
405 | CHECK_TYPEDEF (value_type)(value_type) = check_typedef (value_type); |
406 | |
407 | { |
408 | struct block *b = block_for_pc (funaddr); |
409 | /* If compiled without -g, assume GCC 2. */ |
410 | using_gcc = (b == NULL((void*)0) ? 2 : BLOCK_GCC_COMPILED (b)(b)->gcc_compile_flag); |
411 | } |
412 | |
413 | /* Are we returning a value using a structure return or a normal |
414 | value return? */ |
415 | |
416 | struct_return = using_struct_return (value_type, using_gcc); |
417 | |
418 | /* Determine the location of the breakpoint (and possibly other |
419 | stuff) that the called function will return to. The SPARC, for a |
420 | function returning a structure or union, needs to make space for |
421 | not just the breakpoint but also an extra word containing the |
422 | size (?) of the structure being passed. */ |
423 | |
424 | /* The actual breakpoint (at BP_ADDR) is inserted separatly so there |
425 | is no need to write that out. */ |
426 | |
427 | switch (CALL_DUMMY_LOCATION(gdbarch_call_dummy_location (current_gdbarch))) |
428 | { |
429 | case ON_STACK1: |
430 | /* "dummy_addr" is here just to keep old targets happy. New |
431 | targets return that same information via "sp" and "bp_addr". */ |
432 | if (INNER_THAN (1, 2)(gdbarch_inner_than (current_gdbarch, 1, 2))) |
433 | { |
434 | sp = push_dummy_code (current_gdbarch, sp, funaddr, |
435 | using_gcc, args, nargs, value_type, |
436 | &real_pc, &bp_addr); |
437 | dummy_addr = sp; |
438 | } |
439 | else |
440 | { |
441 | dummy_addr = sp; |
Value stored to 'dummy_addr' is never read | |
442 | sp = push_dummy_code (current_gdbarch, sp, funaddr, |
443 | using_gcc, args, nargs, value_type, |
444 | &real_pc, &bp_addr); |
445 | } |
446 | break; |
447 | case AT_ENTRY_POINT4: |
448 | real_pc = funaddr; |
449 | dummy_addr = entry_point_address (); |
450 | /* Make certain that the address points at real code, and not a |
451 | function descriptor. */ |
452 | dummy_addr = gdbarch_convert_from_func_ptr_addr (current_gdbarch, |
453 | dummy_addr, |
454 | ¤t_target); |
455 | /* A call dummy always consists of just a single breakpoint, so |
456 | it's address is the same as the address of the dummy. */ |
457 | bp_addr = dummy_addr; |
458 | break; |
459 | case AT_SYMBOL5: |
460 | /* Some executables define a symbol __CALL_DUMMY_ADDRESS whose |
461 | address is the location where the breakpoint should be |
462 | placed. Once all targets are using the overhauled frame code |
463 | this can be deleted - ON_STACK is a better option. */ |
464 | { |
465 | struct minimal_symbol *sym; |
466 | |
467 | sym = lookup_minimal_symbol ("__CALL_DUMMY_ADDRESS", NULL((void*)0), NULL((void*)0)); |
468 | real_pc = funaddr; |
469 | if (sym) |
470 | dummy_addr = SYMBOL_VALUE_ADDRESS (sym)(sym)->ginfo.value.address; |
471 | else |
472 | dummy_addr = entry_point_address (); |
473 | /* Make certain that the address points at real code, and not |
474 | a function descriptor. */ |
475 | dummy_addr = gdbarch_convert_from_func_ptr_addr (current_gdbarch, |
476 | dummy_addr, |
477 | ¤t_target); |
478 | /* A call dummy always consists of just a single breakpoint, |
479 | so it's address is the same as the address of the dummy. */ |
480 | bp_addr = dummy_addr; |
481 | break; |
482 | } |
483 | default: |
484 | internal_error (__FILE__"/usr/src/gnu/usr.bin/binutils/gdb/infcall.c", __LINE__484, "bad switch"); |
485 | } |
486 | |
487 | if (nargs < TYPE_NFIELDS (ftype)(ftype)->main_type->nfields) |
488 | error ("too few arguments in function call"); |
489 | |
490 | { |
491 | int i; |
492 | for (i = nargs - 1; i >= 0; i--) |
493 | { |
494 | int prototyped; |
495 | struct type *param_type; |
496 | |
497 | /* FIXME drow/2002-05-31: Should just always mark methods as |
498 | prototyped. Can we respect TYPE_VARARGS? Probably not. */ |
499 | if (TYPE_CODE (ftype)(ftype)->main_type->code == TYPE_CODE_METHOD) |
500 | prototyped = 1; |
501 | else if (i < TYPE_NFIELDS (ftype)(ftype)->main_type->nfields) |
502 | prototyped = TYPE_PROTOTYPED (ftype)((ftype)->main_type->flags & (1 << 7)); |
503 | else |
504 | prototyped = 0; |
505 | |
506 | if (i < TYPE_NFIELDS (ftype)(ftype)->main_type->nfields) |
507 | param_type = TYPE_FIELD_TYPE (ftype, i)(((ftype)->main_type->fields[i]).type); |
508 | else |
509 | param_type = NULL((void*)0); |
510 | |
511 | args[i] = value_arg_coerce (args[i], param_type, prototyped); |
512 | |
513 | /* elz: this code is to handle the case in which the function |
514 | to be called has a pointer to function as parameter and the |
515 | corresponding actual argument is the address of a function |
516 | and not a pointer to function variable. In aCC compiled |
517 | code, the calls through pointers to functions (in the body |
518 | of the function called by hand) are made via |
519 | $$dyncall_external which requires some registers setting, |
520 | this is taken care of if we call via a function pointer |
521 | variable, but not via a function address. In cc this is |
522 | not a problem. */ |
523 | |
524 | if (using_gcc == 0) |
525 | { |
526 | if (param_type != NULL((void*)0) && TYPE_CODE (ftype)(ftype)->main_type->code != TYPE_CODE_METHOD) |
527 | { |
528 | /* if this parameter is a pointer to function. */ |
529 | if (TYPE_CODE (param_type)(param_type)->main_type->code == TYPE_CODE_PTR) |
530 | if (TYPE_CODE (TYPE_TARGET_TYPE (param_type))((param_type)->main_type->target_type)->main_type-> code == TYPE_CODE_FUNC) |
531 | /* elz: FIXME here should go the test about the |
532 | compiler used to compile the target. We want to |
533 | issue the error message only if the compiler |
534 | used was HP's aCC. If we used HP's cc, then |
535 | there is no problem and no need to return at |
536 | this point. */ |
537 | /* Go see if the actual parameter is a variable of |
538 | type pointer to function or just a function. */ |
539 | if (args[i]->lval == not_lval) |
540 | { |
541 | char *arg_name; |
542 | if (find_pc_partial_function ((CORE_ADDR) args[i]->aligner.contents[0], &arg_name, NULL((void*)0), NULL((void*)0))) |
543 | error ("\ |
544 | You cannot use function <%s> as argument. \n\ |
545 | You must use a pointer to function type variable. Command ignored.", arg_name); |
546 | } |
547 | } |
548 | } |
549 | } |
550 | } |
551 | |
552 | if (DEPRECATED_REG_STRUCT_HAS_ADDR_P ()(gdbarch_deprecated_reg_struct_has_addr_p (current_gdbarch))) |
553 | { |
554 | int i; |
555 | /* This is a machine like the sparc, where we may need to pass a |
556 | pointer to the structure, not the structure itself. */ |
557 | for (i = nargs - 1; i >= 0; i--) |
558 | { |
559 | struct type *arg_type = check_typedef (VALUE_TYPE (args[i])(args[i])->type); |
560 | if ((TYPE_CODE (arg_type)(arg_type)->main_type->code == TYPE_CODE_STRUCT |
561 | || TYPE_CODE (arg_type)(arg_type)->main_type->code == TYPE_CODE_UNION |
562 | || TYPE_CODE (arg_type)(arg_type)->main_type->code == TYPE_CODE_ARRAY |
563 | || TYPE_CODE (arg_type)(arg_type)->main_type->code == TYPE_CODE_STRING |
564 | || TYPE_CODE (arg_type)(arg_type)->main_type->code == TYPE_CODE_BITSTRING |
565 | || TYPE_CODE (arg_type)(arg_type)->main_type->code == TYPE_CODE_SET |
566 | || (TYPE_CODE (arg_type)(arg_type)->main_type->code == TYPE_CODE_FLT |
567 | && TYPE_LENGTH (arg_type)(arg_type)->length > 8) |
568 | ) |
569 | && DEPRECATED_REG_STRUCT_HAS_ADDR (using_gcc, arg_type)(gdbarch_deprecated_reg_struct_has_addr (current_gdbarch, using_gcc , arg_type))) |
570 | { |
571 | CORE_ADDR addr; |
572 | int len; /* = TYPE_LENGTH (arg_type); */ |
573 | int aligned_len; |
574 | arg_type = check_typedef (VALUE_ENCLOSING_TYPE (args[i])(args[i])->enclosing_type); |
575 | len = TYPE_LENGTH (arg_type)(arg_type)->length; |
576 | |
577 | aligned_len = len; |
578 | if (INNER_THAN (1, 2)(gdbarch_inner_than (current_gdbarch, 1, 2))) |
579 | { |
580 | /* stack grows downward */ |
581 | sp -= aligned_len; |
582 | /* ... so the address of the thing we push is the |
583 | stack pointer after we push it. */ |
584 | addr = sp; |
585 | } |
586 | else |
587 | { |
588 | /* The stack grows up, so the address of the thing |
589 | we push is the stack pointer before we push it. */ |
590 | addr = sp; |
591 | sp += aligned_len; |
592 | } |
593 | /* Push the structure. */ |
594 | write_memory (addr, VALUE_CONTENTS_ALL (args[i])((void) ((args[i])->lazy && value_fetch_lazy(args[ i])), ((char *) (args[i])->aligner.contents)), len); |
595 | /* The value we're going to pass is the address of the |
596 | thing we just pushed. */ |
597 | /*args[i] = value_from_longest (lookup_pointer_type (value_type), |
598 | (LONGEST) addr); */ |
599 | args[i] = value_from_pointer (lookup_pointer_type (arg_type), |
600 | addr); |
601 | } |
602 | } |
603 | } |
604 | |
605 | |
606 | /* Reserve space for the return structure to be written on the |
607 | stack, if necessary. Make certain that the value is correctly |
608 | aligned. */ |
609 | |
610 | if (struct_return) |
611 | { |
612 | int len = TYPE_LENGTH (value_type)(value_type)->length; |
613 | if (INNER_THAN (1, 2)(gdbarch_inner_than (current_gdbarch, 1, 2))) |
614 | { |
615 | /* Stack grows downward. Align STRUCT_ADDR and SP after |
616 | making space for the return value. */ |
617 | sp -= len; |
618 | if (gdbarch_frame_align_p (current_gdbarch)) |
619 | sp = gdbarch_frame_align (current_gdbarch, sp); |
620 | struct_addr = sp; |
621 | } |
622 | else |
623 | { |
624 | /* Stack grows upward. Align the frame, allocate space, and |
625 | then again, re-align the frame??? */ |
626 | if (gdbarch_frame_align_p (current_gdbarch)) |
627 | sp = gdbarch_frame_align (current_gdbarch, sp); |
628 | struct_addr = sp; |
629 | sp += len; |
630 | if (gdbarch_frame_align_p (current_gdbarch)) |
631 | sp = gdbarch_frame_align (current_gdbarch, sp); |
632 | } |
633 | } |
634 | |
635 | /* Create the dummy stack frame. Pass in the call dummy address as, |
636 | presumably, the ABI code knows where, in the call dummy, the |
637 | return address should be pointed. */ |
638 | if (gdbarch_push_dummy_call_p (current_gdbarch)) |
639 | /* When there is no push_dummy_call method, should this code |
640 | simply error out. That would the implementation of this method |
641 | for all ABIs (which is probably a good thing). */ |
642 | sp = gdbarch_push_dummy_call (current_gdbarch, function, current_regcache, |
643 | bp_addr, nargs, args, sp, struct_return, |
644 | struct_addr); |
645 | else if (DEPRECATED_PUSH_ARGUMENTS_P ()(gdbarch_deprecated_push_arguments_p (current_gdbarch))) |
646 | /* Keep old targets working. */ |
647 | sp = DEPRECATED_PUSH_ARGUMENTS (nargs, args, sp, struct_return,(gdbarch_deprecated_push_arguments (current_gdbarch, nargs, args , sp, struct_return, struct_addr)) |
648 | struct_addr)(gdbarch_deprecated_push_arguments (current_gdbarch, nargs, args , sp, struct_return, struct_addr)); |
649 | else |
650 | error ("This target does not support function calls"); |
651 | |
652 | /* Set up a frame ID for the dummy frame so we can pass it to |
653 | set_momentary_breakpoint. We need to give the breakpoint a frame |
654 | ID so that the breakpoint code can correctly re-identify the |
655 | dummy breakpoint. */ |
656 | /* Sanity. The exact same SP value is returned by PUSH_DUMMY_CALL, |
657 | saved as the dummy-frame TOS, and used by unwind_dummy_id to form |
658 | the frame ID's stack address. */ |
659 | dummy_id = frame_id_build (sp, bp_addr); |
660 | |
661 | /* Create a momentary breakpoint at the return address of the |
662 | inferior. That way it breaks when it returns. */ |
663 | |
664 | { |
665 | struct breakpoint *bpt; |
666 | struct symtab_and_line sal; |
667 | init_sal (&sal); /* initialize to zeroes */ |
668 | sal.pc = bp_addr; |
669 | sal.section = find_pc_overlay (sal.pc); |
670 | /* Sanity. The exact same SP value is returned by |
671 | PUSH_DUMMY_CALL, saved as the dummy-frame TOS, and used by |
672 | unwind_dummy_id to form the frame ID's stack address. */ |
673 | bpt = set_momentary_breakpoint (sal, dummy_id, bp_call_dummy); |
674 | bpt->disposition = disp_del; |
675 | } |
676 | |
677 | /* Everything's ready, push all the info needed to restore the |
678 | caller (and identify the dummy-frame) onto the dummy-frame |
679 | stack. */ |
680 | dummy_frame_push (caller_regcache, &dummy_id); |
681 | discard_cleanups (caller_regcache_cleanup); |
682 | |
683 | /* - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - |
684 | If you're looking to implement asynchronous dummy-frames, then |
685 | just below is the place to chop this function in two.. */ |
686 | |
687 | /* Now proceed, having reached the desired place. */ |
688 | clear_proceed_status (); |
689 | |
690 | /* Execute a "stack dummy", a piece of code stored in the stack by |
691 | the debugger to be executed in the inferior. |
692 | |
693 | The dummy's frame is automatically popped whenever that break is |
694 | hit. If that is the first time the program stops, |
695 | call_function_by_hand returns to its caller with that frame |
696 | already gone and sets RC to 0. |
697 | |
698 | Otherwise, set RC to a non-zero value. If the called function |
699 | receives a random signal, we do not allow the user to continue |
700 | executing it as this may not work. The dummy frame is poped and |
701 | we return 1. If we hit a breakpoint, we leave the frame in place |
702 | and return 2 (the frame will eventually be popped when we do hit |
703 | the dummy end breakpoint). */ |
704 | |
705 | { |
706 | struct cleanup *old_cleanups = make_cleanup (null_cleanup, 0); |
707 | int saved_async = 0; |
708 | |
709 | /* If all error()s out of proceed ended up calling normal_stop |
710 | (and perhaps they should; it already does in the special case |
711 | of error out of resume()), then we wouldn't need this. */ |
712 | make_cleanup (breakpoint_auto_delete_contents, &stop_bpstat); |
713 | |
714 | disable_watchpoints_before_interactive_call_start (); |
715 | proceed_to_finish = 1; /* We want stop_registers, please... */ |
716 | |
717 | if (target_can_async_p ()(current_target.to_can_async_p ())) |
718 | saved_async = target_async_mask (0); |
719 | |
720 | proceed (real_pc, TARGET_SIGNAL_0, 0); |
721 | |
722 | if (saved_async) |
723 | target_async_mask (saved_async); |
724 | |
725 | enable_watchpoints_after_interactive_call_stop (); |
726 | |
727 | discard_cleanups (old_cleanups); |
728 | } |
729 | |
730 | if (stopped_by_random_signal || !stop_stack_dummy) |
731 | { |
732 | /* Find the name of the function we're about to complain about. */ |
733 | const char *name = NULL((void*)0); |
734 | { |
735 | struct symbol *symbol = find_pc_function (funaddr); |
736 | if (symbol) |
737 | name = SYMBOL_PRINT_NAME (symbol)(demangle ? (symbol_natural_name (&(symbol)->ginfo)) : (symbol)->ginfo.name); |
738 | else |
739 | { |
740 | /* Try the minimal symbols. */ |
741 | struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (funaddr); |
742 | if (msymbol) |
743 | name = SYMBOL_PRINT_NAME (msymbol)(demangle ? (symbol_natural_name (&(msymbol)->ginfo)) : (msymbol)->ginfo.name); |
744 | } |
745 | if (name == NULL((void*)0)) |
746 | { |
747 | /* Can't use a cleanup here. It is discarded, instead use |
748 | an alloca. */ |
749 | char *tmp = xstrprintf ("at %s", hex_string (funaddr)); |
750 | char *a = alloca (strlen (tmp) + 1)__builtin_alloca(strlen (tmp) + 1); |
751 | strcpy (a, tmp); |
752 | xfree (tmp); |
753 | name = a; |
754 | } |
755 | } |
756 | if (stopped_by_random_signal) |
757 | { |
758 | /* We stopped inside the FUNCTION because of a random |
759 | signal. Further execution of the FUNCTION is not |
760 | allowed. */ |
761 | |
762 | if (unwind_on_signal_p) |
763 | { |
764 | /* The user wants the context restored. */ |
765 | |
766 | /* We must get back to the frame we were before the |
767 | dummy call. */ |
768 | frame_pop (get_current_frame ()); |
769 | |
770 | /* FIXME: Insert a bunch of wrap_here; name can be very |
771 | long if it's a C++ name with arguments and stuff. */ |
772 | error ("\ |
773 | The program being debugged was signaled while in a function called from GDB.\n\ |
774 | GDB has restored the context to what it was before the call.\n\ |
775 | To change this behavior use \"set unwindonsignal off\"\n\ |
776 | Evaluation of the expression containing the function (%s) will be abandoned.", |
777 | name); |
778 | } |
779 | else |
780 | { |
781 | /* The user wants to stay in the frame where we stopped |
782 | (default).*/ |
783 | /* If we restored the inferior status (via the cleanup), |
784 | we would print a spurious error message (Unable to |
785 | restore previously selected frame), would write the |
786 | registers from the inf_status (which is wrong), and |
787 | would do other wrong things. */ |
788 | discard_cleanups (inf_status_cleanup); |
789 | discard_inferior_status (inf_status); |
790 | /* FIXME: Insert a bunch of wrap_here; name can be very |
791 | long if it's a C++ name with arguments and stuff. */ |
792 | error ("\ |
793 | The program being debugged was signaled while in a function called from GDB.\n\ |
794 | GDB remains in the frame where the signal was received.\n\ |
795 | To change this behavior use \"set unwindonsignal on\"\n\ |
796 | Evaluation of the expression containing the function (%s) will be abandoned.", |
797 | name); |
798 | } |
799 | } |
800 | |
801 | if (!stop_stack_dummy) |
802 | { |
803 | /* We hit a breakpoint inside the FUNCTION. */ |
804 | /* If we restored the inferior status (via the cleanup), we |
805 | would print a spurious error message (Unable to restore |
806 | previously selected frame), would write the registers |
807 | from the inf_status (which is wrong), and would do other |
808 | wrong things. */ |
809 | discard_cleanups (inf_status_cleanup); |
810 | discard_inferior_status (inf_status); |
811 | /* The following error message used to say "The expression |
812 | which contained the function call has been discarded." |
813 | It is a hard concept to explain in a few words. Ideally, |
814 | GDB would be able to resume evaluation of the expression |
815 | when the function finally is done executing. Perhaps |
816 | someday this will be implemented (it would not be easy). */ |
817 | /* FIXME: Insert a bunch of wrap_here; name can be very long if it's |
818 | a C++ name with arguments and stuff. */ |
819 | error ("\ |
820 | The program being debugged stopped while in a function called from GDB.\n\ |
821 | When the function (%s) is done executing, GDB will silently\n\ |
822 | stop (instead of continuing to evaluate the expression containing\n\ |
823 | the function call).", name); |
824 | } |
825 | |
826 | /* The above code errors out, so ... */ |
827 | internal_error (__FILE__"/usr/src/gnu/usr.bin/binutils/gdb/infcall.c", __LINE__827, "... should not be here"); |
828 | } |
829 | |
830 | /* If we get here the called FUNCTION run to completion. */ |
831 | |
832 | /* On normal return, the stack dummy has been popped already. */ |
833 | regcache_cpy_no_passthrough (retbuf, stop_registers); |
834 | |
835 | /* Restore the inferior status, via its cleanup. At this stage, |
836 | leave the RETBUF alone. */ |
837 | do_cleanups (inf_status_cleanup); |
838 | |
839 | /* Figure out the value returned by the function, return that. */ |
840 | { |
841 | struct value *retval; |
842 | if (TYPE_CODE (value_type)(value_type)->main_type->code == TYPE_CODE_VOID) |
843 | /* If the function returns void, don't bother fetching the |
844 | return value. */ |
845 | retval = allocate_value (value_type); |
846 | else if (struct_return) |
847 | /* NOTE: cagney/2003-09-27: This assumes that PUSH_DUMMY_CALL |
848 | has correctly stored STRUCT_ADDR in the target. In the past |
849 | that hasn't been the case, the old MIPS PUSH_ARGUMENTS |
850 | (PUSH_DUMMY_CALL precursor) would silently move the location |
851 | of the struct return value making STRUCT_ADDR bogus. If |
852 | you're seeing problems with values being returned using the |
853 | "struct return convention", check that PUSH_DUMMY_CALL isn't |
854 | playing tricks. */ |
855 | retval = value_at (value_type, struct_addr, NULL((void*)0)); |
856 | else |
857 | { |
858 | /* This code only handles "register convention". */ |
859 | retval = allocate_value (value_type); |
860 | gdb_assert (gdbarch_return_value (current_gdbarch, value_type,((void) ((gdbarch_return_value (current_gdbarch, value_type, ( (void*)0), ((void*)0), ((void*)0)) == RETURN_VALUE_REGISTER_CONVENTION ) ? 0 : (internal_error ("/usr/src/gnu/usr.bin/binutils/gdb/infcall.c" , 862, "%s: Assertion `%s' failed.", __PRETTY_FUNCTION__, "gdbarch_return_value (current_gdbarch, value_type, NULL, NULL, NULL) == RETURN_VALUE_REGISTER_CONVENTION" ), 0))) |
861 | NULL, NULL, NULL)((void) ((gdbarch_return_value (current_gdbarch, value_type, ( (void*)0), ((void*)0), ((void*)0)) == RETURN_VALUE_REGISTER_CONVENTION ) ? 0 : (internal_error ("/usr/src/gnu/usr.bin/binutils/gdb/infcall.c" , 862, "%s: Assertion `%s' failed.", __PRETTY_FUNCTION__, "gdbarch_return_value (current_gdbarch, value_type, NULL, NULL, NULL) == RETURN_VALUE_REGISTER_CONVENTION" ), 0))) |
862 | == RETURN_VALUE_REGISTER_CONVENTION)((void) ((gdbarch_return_value (current_gdbarch, value_type, ( (void*)0), ((void*)0), ((void*)0)) == RETURN_VALUE_REGISTER_CONVENTION ) ? 0 : (internal_error ("/usr/src/gnu/usr.bin/binutils/gdb/infcall.c" , 862, "%s: Assertion `%s' failed.", __PRETTY_FUNCTION__, "gdbarch_return_value (current_gdbarch, value_type, NULL, NULL, NULL) == RETURN_VALUE_REGISTER_CONVENTION" ), 0))); |
863 | gdbarch_return_value (current_gdbarch, value_type, retbuf, |
864 | VALUE_CONTENTS_RAW (retval)((char *) (retval)->aligner.contents + (retval)->embedded_offset ) /*read*/, |
865 | NULL((void*)0) /*write*/); |
866 | } |
867 | do_cleanups (retbuf_cleanup); |
868 | return retval; |
869 | } |
870 | } |
871 | |
872 | void _initialize_infcall (void); |
873 | |
874 | void |
875 | _initialize_infcall (void) |
876 | { |
877 | add_setshow_boolean_cmd ("coerce-float-to-double", class_obscure, |
878 | &coerce_float_to_double_p, "\ |
879 | Set coercion of floats to doubles when calling functions.", "\ |
880 | Show coercion of floats to doubles when calling functions", "\ |
881 | Variables of type float should generally be converted to doubles before\n\ |
882 | calling an unprototyped function, and left alone when calling a prototyped\n\ |
883 | function. However, some older debug info formats do not provide enough\n\ |
884 | information to determine that a function is prototyped. If this flag is\n\ |
885 | set, GDB will perform the conversion for a function it considers\n\ |
886 | unprototyped.\n\ |
887 | The default is to perform the conversion.\n", "\ |
888 | Coercion of floats to doubles when calling functions is %s.", |
889 | NULL((void*)0), NULL((void*)0), &setlist, &showlist); |
890 | |
891 | add_setshow_boolean_cmd ("unwindonsignal", no_class, |
892 | &unwind_on_signal_p, "\ |
893 | Set unwinding of stack if a signal is received while in a call dummy.", "\ |
894 | Show unwinding of stack if a signal is received while in a call dummy.", "\ |
895 | The unwindonsignal lets the user determine what gdb should do if a signal\n\ |
896 | is received while in a function called from gdb (call dummy). If set, gdb\n\ |
897 | unwinds the stack and restore the context to what as it was before the call.\n\ |
898 | The default is to stop in the frame where the signal was received.", "\ |
899 | Unwinding of stack if a signal is received while in a call dummy is %s.", |
900 | NULL((void*)0), NULL((void*)0), &setlist, &showlist); |
901 | } |