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Commit | Line | Data |
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8d08fdba | 1 | /* Handle exceptional things in C++. |
d6a8bdff | 2 | Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000 |
158991b7 | 3 | Free Software Foundation, Inc. |
8d2733ca MS |
4 | Contributed by Michael Tiemann <tiemann@cygnus.com> |
5 | Rewritten by Mike Stump <mrs@cygnus.com>, based upon an | |
6 | initial re-implementation courtesy Tad Hunt. | |
8d08fdba MS |
7 | |
8 | This file is part of GNU CC. | |
9 | ||
10 | GNU CC is free software; you can redistribute it and/or modify | |
11 | it under the terms of the GNU General Public License as published by | |
12 | the Free Software Foundation; either version 2, or (at your option) | |
13 | any later version. | |
14 | ||
15 | GNU CC is distributed in the hope that it will be useful, | |
16 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
18 | GNU General Public License for more details. | |
19 | ||
20 | You should have received a copy of the GNU General Public License | |
21 | along with GNU CC; see the file COPYING. If not, write to | |
e9fa0c7c RK |
22 | the Free Software Foundation, 59 Temple Place - Suite 330, |
23 | Boston, MA 02111-1307, USA. */ | |
8d08fdba MS |
24 | |
25 | ||
8d08fdba | 26 | #include "config.h" |
8d052bc7 | 27 | #include "system.h" |
8d08fdba MS |
28 | #include "tree.h" |
29 | #include "rtl.h" | |
8f17b5c5 | 30 | #include "expr.h" |
8d08fdba MS |
31 | #include "cp-tree.h" |
32 | #include "flags.h" | |
8d2733ca | 33 | #include "obstack.h" |
21451173 | 34 | #include "output.h" |
6467930b | 35 | #include "except.h" |
0021b564 | 36 | #include "defaults.h" |
54f92bfb | 37 | #include "toplev.h" |
9a0d1e1b | 38 | #include "eh-common.h" |
8d08fdba | 39 | |
93ca4ba7 | 40 | static void push_eh_cleanup PARAMS ((tree)); |
158991b7 KG |
41 | static tree build_eh_type_type PARAMS ((tree)); |
42 | static tree call_eh_info PARAMS ((void)); | |
43 | static void push_eh_info PARAMS ((void)); | |
44 | static tree get_eh_info PARAMS ((void)); | |
45 | static tree get_eh_value PARAMS ((void)); | |
87603ed0 | 46 | #if 0 |
158991b7 KG |
47 | static tree get_eh_type PARAMS ((void)); |
48 | static tree get_eh_caught PARAMS ((void)); | |
49 | static tree get_eh_handlers PARAMS ((void)); | |
e833cb11 | 50 | #endif |
93ca4ba7 JM |
51 | static int dtor_nothrow PARAMS ((tree)); |
52 | static tree do_pop_exception PARAMS ((tree)); | |
158991b7 KG |
53 | static tree build_eh_type_type_ref PARAMS ((tree)); |
54 | static tree build_terminate_handler PARAMS ((void)); | |
55 | static tree alloc_eh_object PARAMS ((tree)); | |
56 | static int complete_ptr_ref_or_void_ptr_p PARAMS ((tree, tree)); | |
fbd40359 ZW |
57 | static int can_convert_eh PARAMS ((tree, tree)); |
58 | static void check_handlers_1 PARAMS ((tree, tree)); | |
158991b7 KG |
59 | static void initialize_handler_parm PARAMS ((tree)); |
60 | static tree expand_throw PARAMS ((tree)); | |
e97f22c9 | 61 | static int decl_is_java_type PARAMS ((tree decl, int err)); |
8d2733ca | 62 | |
8d2733ca | 63 | #include "decl.h" |
8d2733ca MS |
64 | #include "insn-flags.h" |
65 | #include "obstack.h" | |
8d2733ca | 66 | |
e97f22c9 TT |
67 | /* In a given translation unit we are constrained to catch only C++ |
68 | types or only Java types. `catch_language' holds the current type, | |
69 | and `catch_language_init' registers whether `catch_language' has | |
70 | been set. */ | |
71 | ||
72 | static int catch_language_init = 0; | |
73 | static int catch_language; | |
74 | ||
8d2733ca MS |
75 | /* ====================================================================== |
76 | Briefly the algorithm works like this: | |
77 | ||
78 | When a constructor or start of a try block is encountered, | |
79 | push_eh_entry (&eh_stack) is called. Push_eh_entry () creates a | |
80 | new entry in the unwind protection stack and returns a label to | |
81 | output to start the protection for that block. | |
82 | ||
83 | When a destructor or end try block is encountered, pop_eh_entry | |
6467930b MS |
84 | (&eh_stack) is called. Pop_eh_entry () returns the eh_entry it |
85 | created when push_eh_entry () was called. The eh_entry structure | |
8d2733ca MS |
86 | contains three things at this point. The start protect label, |
87 | the end protect label, and the exception handler label. The end | |
88 | protect label should be output before the call to the destructor | |
89 | (if any). If it was a destructor, then its parse tree is stored | |
6467930b | 90 | in the finalization variable in the eh_entry structure. Otherwise |
8d2733ca | 91 | the finalization variable is set to NULL to reflect the fact that |
38e01259 | 92 | it is the end of a try block. Next, this modified eh_entry node |
8d2733ca MS |
93 | is enqueued in the finalizations queue by calling |
94 | enqueue_eh_entry (&queue,entry). | |
95 | ||
96 | +---------------------------------------------------------------+ | |
97 | |XXX: Will need modification to deal with partially | | |
98 | | constructed arrays of objects | | |
99 | | | | |
100 | | Basically, this consists of keeping track of how many | | |
101 | | of the objects have been constructed already (this | | |
102 | | should be in a register though, so that shouldn't be a | | |
103 | | problem. | | |
104 | +---------------------------------------------------------------+ | |
105 | ||
106 | When a catch block is encountered, there is a lot of work to be | |
107 | done. | |
108 | ||
109 | Since we don't want to generate the catch block inline with the | |
110 | regular flow of the function, we need to have some way of doing | |
f30432d7 MS |
111 | so. Luckily, we can use sequences to defer the catch sections. |
112 | When the start of a catch block is encountered, we start the | |
113 | sequence. After the catch block is generated, we end the | |
114 | sequence. | |
115 | ||
8d2733ca MS |
116 | Next we must insure that when the catch block is executed, all |
117 | finalizations for the matching try block have been completed. If | |
118 | any of those finalizations throw an exception, we must call | |
119 | terminate according to the ARM (section r.15.6.1). What this | |
120 | means is that we need to dequeue and emit finalizations for each | |
6467930b | 121 | entry in the eh_queue until we get to an entry with a NULL |
8d2733ca MS |
122 | finalization field. For any of the finalization entries, if it |
123 | is not a call to terminate (), we must protect it by giving it | |
124 | another start label, end label, and exception handler label, | |
125 | setting its finalization tree to be a call to terminate (), and | |
6467930b | 126 | enqueue'ing this new eh_entry to be output at an outer level. |
8d2733ca MS |
127 | Finally, after all that is done, we can get around to outputting |
128 | the catch block which basically wraps all the "catch (...) {...}" | |
129 | statements in a big if/then/else construct that matches the | |
130 | correct block to call. | |
131 | ||
132 | ===================================================================== */ | |
133 | ||
8d2733ca MS |
134 | /* ====================================================================== */ |
135 | ||
8d2733ca | 136 | /* sets up all the global eh stuff that needs to be initialized at the |
bbd0d54a | 137 | start of compilation. */ |
8d08fdba | 138 | |
8d08fdba | 139 | void |
8d2733ca | 140 | init_exception_processing () |
8d08fdba | 141 | { |
6633d636 MS |
142 | /* void vtype () */ |
143 | tree vtype = build_function_type (void_type_node, void_list_node); | |
144 | ||
2c73f9f5 | 145 | if (flag_honor_std) |
6bcedb4e | 146 | push_namespace (std_identifier); |
0c11ada6 | 147 | terminate_node = build_cp_library_fn_ptr ("terminate", vtype); |
9cd64686 | 148 | TREE_THIS_VOLATILE (terminate_node) = 1; |
0c11ada6 | 149 | TREE_NOTHROW (terminate_node) = 1; |
2c73f9f5 ML |
150 | if (flag_honor_std) |
151 | pop_namespace (); | |
8ccc31eb | 152 | |
9a0d1e1b AM |
153 | set_exception_lang_code (EH_LANG_C_plus_plus); |
154 | set_exception_version_code (1); | |
9a0d1e1b | 155 | |
eb66be0e MS |
156 | /* If we use setjmp/longjmp EH, arrange for all cleanup actions to |
157 | be protected with __terminate. */ | |
158 | protect_cleanup_actions_with_terminate = 1; | |
8d2733ca MS |
159 | } |
160 | ||
95e8dcba | 161 | /* Retrieve a pointer to the cp_eh_info node for the current exception. */ |
6874c264 | 162 | |
95e8dcba JM |
163 | static tree |
164 | call_eh_info () | |
6874c264 | 165 | { |
95e8dcba | 166 | tree fn; |
6874c264 | 167 | |
e6cfb550 | 168 | fn = get_identifier ("__start_cp_handler"); |
6874c264 JM |
169 | if (IDENTIFIER_GLOBAL_VALUE (fn)) |
170 | fn = IDENTIFIER_GLOBAL_VALUE (fn); | |
171 | else | |
172 | { | |
a1622f83 | 173 | tree t1, t, fields[7]; |
6874c264 | 174 | |
e6cfb550 | 175 | /* Declare cp_eh_info * __start_cp_handler (void), |
6874c264 | 176 | as defined in exception.cc. */ |
6874c264 JM |
177 | |
178 | /* struct cp_eh_info. This must match exception.cc. Note that this | |
179 | type is not pushed anywhere. */ | |
33848bb0 | 180 | t1= make_aggr_type (RECORD_TYPE); |
721c3b42 | 181 | fields[0] = build_decl (FIELD_DECL, |
9a0d1e1b | 182 | get_identifier ("handler_label"), ptr_type_node); |
721c3b42 | 183 | fields[1] = build_decl (FIELD_DECL, |
9a0d1e1b | 184 | get_identifier ("dynamic_handler_chain"), ptr_type_node); |
721c3b42 | 185 | fields[2] = build_decl (FIELD_DECL, |
9a0d1e1b | 186 | get_identifier ("info"), ptr_type_node); |
721c3b42 | 187 | fields[3] = build_decl (FIELD_DECL, |
e6cfb550 | 188 | get_identifier ("table_index"), ptr_type_node); |
9a0d1e1b AM |
189 | /* N.B.: The fourth field LEN is expected to be |
190 | the number of fields - 1, not the total number of fields. */ | |
e6cfb550 | 191 | finish_builtin_type (t1, "eh_context", fields, 3, ptr_type_node); |
9a0d1e1b AM |
192 | t1 = build_pointer_type (t1); |
193 | ||
33848bb0 | 194 | t1= make_aggr_type (RECORD_TYPE); |
721c3b42 | 195 | fields[0] = build_decl (FIELD_DECL, |
9a0d1e1b | 196 | get_identifier ("match_function"), ptr_type_node); |
721c3b42 | 197 | fields[1] = build_decl (FIELD_DECL, |
9a0d1e1b | 198 | get_identifier ("language"), short_integer_type_node); |
721c3b42 | 199 | fields[2] = build_decl (FIELD_DECL, |
9a0d1e1b AM |
200 | get_identifier ("version"), short_integer_type_node); |
201 | /* N.B.: The fourth field LEN is expected to be | |
202 | the number of fields - 1, not the total number of fields. */ | |
5816cb14 | 203 | finish_builtin_type (t1, "__eh_info", fields, 2, ptr_type_node); |
33848bb0 | 204 | t = make_aggr_type (RECORD_TYPE); |
721c3b42 MM |
205 | fields[0] = build_decl (FIELD_DECL, |
206 | get_identifier ("eh_info"), t1); | |
207 | fields[1] = build_decl (FIELD_DECL, get_identifier ("value"), | |
208 | ptr_type_node); | |
209 | fields[2] = build_decl (FIELD_DECL, get_identifier ("type"), | |
210 | ptr_type_node); | |
211 | fields[3] = build_decl | |
6874c264 JM |
212 | (FIELD_DECL, get_identifier ("cleanup"), |
213 | build_pointer_type (build_function_type | |
214 | (ptr_type_node, tree_cons | |
215 | (NULL_TREE, ptr_type_node, void_list_node)))); | |
721c3b42 MM |
216 | fields[4] = build_decl (FIELD_DECL, get_identifier ("caught"), |
217 | boolean_type_node); | |
218 | fields[5] = build_decl (FIELD_DECL, get_identifier ("next"), | |
219 | build_pointer_type (t)); | |
220 | fields[6] = build_decl | |
20b90169 | 221 | (FIELD_DECL, get_identifier ("handlers"), long_integer_type_node); |
cf9d67e3 BK |
222 | /* N.B.: The fourth field LEN is expected to be |
223 | the number of fields - 1, not the total number of fields. */ | |
a1622f83 | 224 | finish_builtin_type (t, "cp_eh_info", fields, 6, ptr_type_node); |
6874c264 JM |
225 | t = build_pointer_type (t); |
226 | ||
227 | /* And now the function. */ | |
0c11ada6 | 228 | fn = push_library_fn (fn, build_function_type (t, void_list_node)); |
6874c264 | 229 | } |
95e8dcba JM |
230 | return build_function_call (fn, NULL_TREE); |
231 | } | |
232 | ||
233 | /* Retrieve a pointer to the cp_eh_info node for the current exception | |
234 | and save it in the current binding level. */ | |
235 | ||
236 | static void | |
237 | push_eh_info () | |
238 | { | |
239 | tree decl, fn = call_eh_info (); | |
6874c264 JM |
240 | |
241 | /* Remember the pointer to the current exception info; it won't change | |
242 | during this catch block. */ | |
243 | decl = build_decl (VAR_DECL, get_identifier ("__exception_info"), | |
244 | TREE_TYPE (fn)); | |
245 | DECL_ARTIFICIAL (decl) = 1; | |
246 | DECL_INITIAL (decl) = fn; | |
247 | decl = pushdecl (decl); | |
cd9f6678 | 248 | cp_finish_decl (decl, fn, NULL_TREE, 0); |
6874c264 JM |
249 | } |
250 | ||
251 | /* Returns a reference to the cp_eh_info node for the current exception. */ | |
252 | ||
253 | static tree | |
254 | get_eh_info () | |
255 | { | |
256 | /* Look for the pointer pushed in push_eh_info. */ | |
257 | tree t = lookup_name (get_identifier ("__exception_info"), 0); | |
258 | return build_indirect_ref (t, NULL_PTR); | |
259 | } | |
260 | ||
261 | /* Returns a reference to the current exception object. */ | |
262 | ||
263 | static tree | |
264 | get_eh_value () | |
265 | { | |
266 | return build_component_ref (get_eh_info (), get_identifier ("value"), | |
267 | NULL_TREE, 0); | |
268 | } | |
269 | ||
270 | /* Returns a reference to the current exception type. */ | |
271 | ||
87603ed0 | 272 | #if 0 |
6874c264 JM |
273 | static tree |
274 | get_eh_type () | |
275 | { | |
276 | return build_component_ref (get_eh_info (), get_identifier ("type"), | |
277 | NULL_TREE, 0); | |
278 | } | |
279 | ||
280 | /* Returns a reference to whether or not the current exception | |
281 | has been caught. */ | |
282 | ||
283 | static tree | |
284 | get_eh_caught () | |
285 | { | |
286 | return build_component_ref (get_eh_info (), get_identifier ("caught"), | |
287 | NULL_TREE, 0); | |
288 | } | |
289 | ||
20b90169 JM |
290 | /* Returns a reference to whether or not the current exception |
291 | has been caught. */ | |
292 | ||
293 | static tree | |
294 | get_eh_handlers () | |
295 | { | |
296 | return build_component_ref (get_eh_info (), get_identifier ("handlers"), | |
297 | NULL_TREE, 0); | |
298 | } | |
e833cb11 | 299 | #endif |
20b90169 | 300 | |
f30432d7 MS |
301 | /* Build a type value for use at runtime for a type that is matched |
302 | against by the exception handling system. */ | |
6467930b | 303 | |
f30432d7 MS |
304 | static tree |
305 | build_eh_type_type (type) | |
306 | tree type; | |
8d08fdba | 307 | { |
f30432d7 MS |
308 | if (type == error_mark_node) |
309 | return error_mark_node; | |
8d2733ca | 310 | |
e92cc029 | 311 | /* peel back references, so they match. */ |
f30432d7 MS |
312 | if (TREE_CODE (type) == REFERENCE_TYPE) |
313 | type = TREE_TYPE (type); | |
8d08fdba | 314 | |
e92cc029 | 315 | /* Peel off cv qualifiers. */ |
f30432d7 | 316 | type = TYPE_MAIN_VARIANT (type); |
8d2733ca | 317 | |
db48b831 | 318 | return build1 (ADDR_EXPR, ptr_type_node, get_typeid_1 (type)); |
8d08fdba | 319 | } |
8d08fdba | 320 | |
e5f614d7 | 321 | /* Build the address of a typeinfo decl for use in the runtime |
db48b831 | 322 | matching field of the new exception model */ |
5816cb14 AM |
323 | |
324 | static tree | |
325 | build_eh_type_type_ref (type) | |
326 | tree type; | |
327 | { | |
5816cb14 | 328 | tree exp; |
5816cb14 | 329 | |
93ca4ba7 JM |
330 | if (type == NULL_TREE || type == error_mark_node) |
331 | return type; | |
5816cb14 AM |
332 | |
333 | /* peel back references, so they match. */ | |
334 | if (TREE_CODE (type) == REFERENCE_TYPE) | |
335 | type = TREE_TYPE (type); | |
336 | ||
337 | /* Peel off cv qualifiers. */ | |
338 | type = TYPE_MAIN_VARIANT (type); | |
339 | ||
e5f614d7 NS |
340 | exp = get_tinfo_decl (type); |
341 | mark_used (exp); | |
db48b831 | 342 | exp = build1 (ADDR_EXPR, ptr_type_node, exp); |
5816cb14 | 343 | |
5816cb14 AM |
344 | return (exp); |
345 | } | |
346 | ||
9c606f69 | 347 | /* This routine is called to mark all the symbols representing runtime |
ae673f14 | 348 | type functions in the exception table as having been referenced. |
9c606f69 | 349 | This will make sure code is emitted for them. Called from finish_file. */ |
93ca4ba7 | 350 | |
9c606f69 AM |
351 | void |
352 | mark_all_runtime_matches () | |
353 | { | |
354 | int x,num; | |
355 | void **ptr; | |
356 | tree exp; | |
357 | ||
358 | num = find_all_handler_type_matches (&ptr); | |
359 | if (num == 0 || ptr == NULL) | |
360 | return; | |
361 | ||
362 | for (x=0; x <num; x++) | |
363 | { | |
364 | exp = (tree) ptr[x]; | |
365 | if (TREE_CODE (exp) == ADDR_EXPR) | |
366 | { | |
367 | exp = TREE_OPERAND (exp, 0); | |
368 | if (TREE_CODE (exp) == FUNCTION_DECL) | |
369 | TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (exp)) = 1; | |
370 | } | |
371 | } | |
372 | ||
373 | free (ptr); | |
374 | } | |
375 | ||
93ca4ba7 JM |
376 | /* Returns nonzero if cleaning up an exception of type TYPE (which can be |
377 | NULL_TREE for a ... handler) will not throw an exception. */ | |
378 | ||
379 | static int | |
380 | dtor_nothrow (type) | |
381 | tree type; | |
382 | { | |
383 | tree fn; | |
384 | ||
385 | if (type == NULL_TREE) | |
386 | return 0; | |
387 | ||
388 | if (! TYPE_HAS_DESTRUCTOR (type)) | |
389 | return 1; | |
390 | ||
391 | fn = lookup_member (type, dtor_identifier, 0, 0); | |
392 | fn = TREE_VALUE (fn); | |
393 | return TREE_NOTHROW (fn); | |
394 | } | |
395 | ||
c7ae64f2 | 396 | /* Build up a call to __cp_pop_exception, to destroy the exception object |
93ca4ba7 | 397 | for the current catch block if no others are currently using it. */ |
6467930b | 398 | |
c7ae64f2 | 399 | static tree |
93ca4ba7 JM |
400 | do_pop_exception (type) |
401 | tree type; | |
72b7eeff | 402 | { |
6874c264 | 403 | tree fn, cleanup; |
6874c264 JM |
404 | fn = get_identifier ("__cp_pop_exception"); |
405 | if (IDENTIFIER_GLOBAL_VALUE (fn)) | |
406 | fn = IDENTIFIER_GLOBAL_VALUE (fn); | |
407 | else | |
408 | { | |
c7ae64f2 JM |
409 | /* Declare void __cp_pop_exception (void *), |
410 | as defined in exception.cc. */ | |
0c11ada6 JM |
411 | fn = push_void_library_fn |
412 | (fn, tree_cons (NULL_TREE, ptr_type_node, void_list_node)); | |
413 | /* This can throw if the destructor for the exception throws. */ | |
414 | TREE_NOTHROW (fn) = 0; | |
6874c264 | 415 | } |
72b7eeff MS |
416 | |
417 | /* Arrange to do a dynamically scoped cleanup upon exit from this region. */ | |
c7ae64f2 | 418 | cleanup = lookup_name (get_identifier ("__exception_info"), 0); |
e1b3e07d | 419 | cleanup = build_function_call (fn, tree_cons |
de35891e | 420 | (NULL_TREE, cleanup, NULL_TREE)); |
93ca4ba7 | 421 | TREE_NOTHROW (cleanup) = dtor_nothrow (type); |
c0700ea5 | 422 | return cleanup; |
c7ae64f2 JM |
423 | } |
424 | ||
425 | /* This routine creates the cleanup for the current exception. */ | |
72b7eeff | 426 | |
c7ae64f2 | 427 | static void |
93ca4ba7 JM |
428 | push_eh_cleanup (type) |
429 | tree type; | |
c7ae64f2 | 430 | { |
93ca4ba7 | 431 | finish_decl_cleanup (NULL_TREE, do_pop_exception (type)); |
c7ae64f2 | 432 | } |
72b7eeff | 433 | |
f4a23343 JM |
434 | /* Build up a call to terminate on the function obstack, for use as an |
435 | exception handler. */ | |
436 | ||
c6160f8f | 437 | static tree |
f4a23343 JM |
438 | build_terminate_handler () |
439 | { | |
80048418 | 440 | return build_function_call (terminate_node, NULL_TREE); |
f4a23343 JM |
441 | } |
442 | ||
e97f22c9 TT |
443 | /* Return nonzero value if DECL is a Java type suitable for catch or |
444 | throw. */ | |
445 | ||
446 | static int | |
447 | decl_is_java_type (decl, err) | |
448 | tree decl; | |
449 | int err; | |
450 | { | |
451 | int r = (TREE_CODE (decl) == POINTER_TYPE | |
452 | && TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE | |
453 | && TYPE_FOR_JAVA (TREE_TYPE (decl))); | |
454 | ||
455 | if (err) | |
456 | { | |
457 | if (TREE_CODE (decl) == REFERENCE_TYPE | |
458 | && TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE | |
459 | && TYPE_FOR_JAVA (TREE_TYPE (decl))) | |
460 | { | |
461 | /* Can't throw a reference. */ | |
462 | cp_error ("type `%T' is disallowed in Java `throw' or `catch'", | |
463 | decl); | |
464 | } | |
465 | ||
466 | if (r) | |
467 | { | |
468 | tree jthrow_node | |
469 | = IDENTIFIER_GLOBAL_VALUE (get_identifier ("jthrowable")); | |
470 | if (jthrow_node == NULL_TREE) | |
471 | fatal ("call to Java `catch' or `throw', while `jthrowable' undefined"); | |
472 | jthrow_node = TREE_TYPE (TREE_TYPE (jthrow_node)); | |
473 | ||
474 | if (! DERIVED_FROM_P (jthrow_node, TREE_TYPE (decl))) | |
475 | { | |
476 | /* Thrown object must be a Throwable. */ | |
477 | cp_error ("type `%T' is not derived from `java::lang::Throwable'", | |
478 | TREE_TYPE (decl)); | |
479 | } | |
480 | } | |
481 | } | |
482 | ||
483 | return r; | |
484 | } | |
485 | ||
b35d4555 | 486 | /* Initialize the catch parameter DECL. */ |
6467930b | 487 | |
b35d4555 MM |
488 | static void |
489 | initialize_handler_parm (decl) | |
3c5c0849 | 490 | tree decl; |
8d08fdba | 491 | { |
b35d4555 MM |
492 | tree exp; |
493 | tree init; | |
494 | tree init_type; | |
e97f22c9 | 495 | int lang; |
b35d4555 MM |
496 | |
497 | /* Make sure we mark the catch param as used, otherwise we'll get a | |
498 | warning about an unused ((anonymous)). */ | |
499 | TREE_USED (decl) = 1; | |
500 | ||
501 | /* Figure out the type that the initializer is. */ | |
502 | init_type = TREE_TYPE (decl); | |
503 | if (TREE_CODE (init_type) != REFERENCE_TYPE | |
504 | && TREE_CODE (init_type) != POINTER_TYPE) | |
505 | init_type = build_reference_type (init_type); | |
506 | ||
e97f22c9 TT |
507 | if (decl_is_java_type (init_type, 0)) |
508 | { | |
509 | tree fn | |
510 | = builtin_function ("_Jv_exception_info", | |
511 | build_function_type (ptr_type_node, | |
512 | tree_cons (NULL_TREE, | |
513 | void_type_node, | |
514 | NULL_TREE)), | |
515 | 0, NOT_BUILT_IN, NULL_PTR); | |
516 | ||
517 | exp = build (CALL_EXPR, ptr_type_node, | |
518 | build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (fn)), | |
519 | fn), | |
520 | NULL_TREE, NULL_TREE); | |
521 | TREE_SIDE_EFFECTS (exp) = 1; | |
522 | lang = EH_LANG_Java; | |
523 | ||
524 | set_exception_lang_code (EH_LANG_Java); | |
525 | set_exception_version_code (1); | |
526 | } | |
527 | else | |
528 | { | |
529 | exp = get_eh_value (); | |
530 | lang = EH_LANG_C_plus_plus; | |
531 | } | |
532 | ||
533 | if (catch_language_init) | |
534 | { | |
535 | if (lang != catch_language) | |
536 | error ("mixing C++ and Java `catch'es in single translation unit"); | |
537 | } | |
538 | else | |
539 | { | |
540 | catch_language_init = 1; | |
541 | catch_language = lang; | |
542 | } | |
b35d4555 MM |
543 | |
544 | /* Since pointers are passed by value, initialize a reference to | |
545 | pointer catch parm with the address of the value slot. */ | |
546 | if (TREE_CODE (init_type) == REFERENCE_TYPE | |
547 | && TREE_CODE (TREE_TYPE (init_type)) == POINTER_TYPE) | |
548 | exp = build_unary_op (ADDR_EXPR, exp, 1); | |
549 | ||
550 | exp = ocp_convert (init_type , exp, CONV_IMPLICIT|CONV_FORCE_TEMP, 0); | |
551 | ||
552 | init = convert_from_reference (exp); | |
553 | ||
554 | /* If the constructor for the catch parm exits via an exception, we | |
555 | must call terminate. See eh23.C. */ | |
556 | if (TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl))) | |
faf5394a | 557 | { |
b35d4555 MM |
558 | /* Generate the copy constructor call directly so we can wrap it. |
559 | See also expand_default_init. */ | |
560 | init = ocp_convert (TREE_TYPE (decl), init, | |
561 | CONV_IMPLICIT|CONV_FORCE_TEMP, 0); | |
562 | init = build (TRY_CATCH_EXPR, TREE_TYPE (init), init, | |
563 | build_terminate_handler ()); | |
faf5394a MS |
564 | } |
565 | ||
b35d4555 MM |
566 | /* Let `cp_finish_decl' know that this initializer is ok. */ |
567 | DECL_INITIAL (decl) = error_mark_node; | |
568 | decl = pushdecl (decl); | |
8d2733ca | 569 | |
b35d4555 | 570 | start_decl_1 (decl); |
cd9f6678 | 571 | cp_finish_decl (decl, init, NULL_TREE, |
b35d4555 | 572 | LOOKUP_ONLYCONVERTING|DIRECT_BIND); |
5816cb14 AM |
573 | } |
574 | ||
b35d4555 | 575 | /* Call this to start a catch block. DECL is the catch parameter. */ |
5816cb14 | 576 | |
b35d4555 MM |
577 | tree |
578 | expand_start_catch_block (decl) | |
3c5c0849 | 579 | tree decl; |
5816cb14 | 580 | { |
b35d4555 MM |
581 | tree compound_stmt_1; |
582 | tree compound_stmt_2; | |
5816cb14 | 583 | |
b35d4555 MM |
584 | if (! doing_eh (1)) |
585 | return NULL_TREE; | |
5816cb14 | 586 | |
b35d4555 | 587 | /* Make sure this declaration is reasonable. */ |
3c5c0849 MM |
588 | if (decl && !complete_ptr_ref_or_void_ptr_p (TREE_TYPE (decl), NULL_TREE)) |
589 | decl = NULL_TREE; | |
5816cb14 | 590 | |
b35d4555 MM |
591 | /* Create a binding level for the eh_info and the exception object |
592 | cleanup. */ | |
593 | compound_stmt_1 = begin_compound_stmt (/*has_no_scope=*/0); | |
594 | ||
e97f22c9 TT |
595 | if (! decl || ! decl_is_java_type (TREE_TYPE (decl), 1)) |
596 | { | |
597 | /* The ordinary C++ case. */ | |
93ca4ba7 | 598 | tree type; |
5816cb14 | 599 | |
e97f22c9 | 600 | if (decl) |
93ca4ba7 | 601 | type = TREE_TYPE (decl); |
e97f22c9 TT |
602 | else |
603 | type = NULL_TREE; | |
93ca4ba7 | 604 | begin_catch_block (build_eh_type_type_ref (type)); |
e97f22c9 TT |
605 | |
606 | push_eh_info (); | |
93ca4ba7 | 607 | push_eh_cleanup (type); |
e97f22c9 TT |
608 | } |
609 | else | |
610 | { | |
611 | /* The Java case. In this case, the match_info is a pointer to | |
612 | the Java class object. We assume that the class is a | |
613 | compiled class. */ | |
614 | tree ref = build_java_class_ref (TREE_TYPE (TREE_TYPE (decl))); | |
615 | begin_catch_block (build1 (ADDR_EXPR, jclass_node, ref)); | |
616 | } | |
5816cb14 | 617 | |
b35d4555 MM |
618 | /* Create a binding level for the parm. */ |
619 | compound_stmt_2 = begin_compound_stmt (/*has_no_scope=*/0); | |
5816cb14 | 620 | |
b35d4555 MM |
621 | if (decl) |
622 | initialize_handler_parm (decl); | |
5816cb14 | 623 | |
b35d4555 | 624 | return build_tree_list (compound_stmt_1, compound_stmt_2); |
5816cb14 AM |
625 | } |
626 | ||
f30432d7 | 627 | |
8d2733ca MS |
628 | /* Call this to end a catch block. Its responsible for emitting the |
629 | code to handle jumping back to the correct place, and for emitting | |
630 | the label to jump to if this catch block didn't match. */ | |
6467930b | 631 | |
824b9a4c | 632 | void |
b35d4555 MM |
633 | expand_end_catch_block (blocks) |
634 | tree blocks; | |
8d08fdba | 635 | { |
b35d4555 MM |
636 | tree compound_stmt_1 = blocks ? TREE_PURPOSE (blocks): NULL_TREE; |
637 | tree compound_stmt_2 = blocks ? TREE_VALUE (blocks): NULL_TREE; | |
638 | ||
f30432d7 MS |
639 | if (! doing_eh (1)) |
640 | return; | |
8d2733ca | 641 | |
0dde4175 JM |
642 | /* The exception being handled is rethrown if control reaches the end of |
643 | a handler of the function-try-block of a constructor or destructor. */ | |
644 | if (in_function_try_handler | |
645 | && (DECL_CONSTRUCTOR_P (current_function_decl) | |
646 | || DECL_DESTRUCTOR_P (current_function_decl))) | |
b35d4555 | 647 | finish_expr_stmt (build_throw (NULL_TREE)); |
0dde4175 | 648 | |
c7ae64f2 | 649 | /* Cleanup the EH parameter. */ |
b35d4555 | 650 | finish_compound_stmt (/*has_no_scope=*/0, compound_stmt_2); |
46e8c075 | 651 | /* Cleanup the EH object. */ |
4a6ef811 | 652 | finish_compound_stmt (/*has_no_scope=*/0, compound_stmt_1); |
8d2733ca | 653 | } |
8d08fdba | 654 | |
6c20b7e9 JM |
655 | /* An exception spec is implemented more or less like: |
656 | ||
657 | try { | |
658 | function body; | |
659 | } catch (...) { | |
660 | void *p[] = { typeid(raises) }; | |
661 | __check_eh_spec (p, count); | |
662 | } | |
663 | ||
664 | __check_eh_spec in exception.cc handles all the details. */ | |
8d2733ca | 665 | |
b35d4555 | 666 | tree |
f30432d7 MS |
667 | expand_start_eh_spec () |
668 | { | |
b35d4555 | 669 | return begin_try_block (); |
f30432d7 MS |
670 | } |
671 | ||
b35d4555 MM |
672 | void |
673 | expand_end_eh_spec (raises, try_block) | |
f30432d7 | 674 | tree raises; |
b35d4555 | 675 | tree try_block; |
f30432d7 | 676 | { |
6c20b7e9 | 677 | tree tmp, fn, decl, types = NULL_TREE; |
b35d4555 MM |
678 | tree blocks; |
679 | tree handler; | |
6c20b7e9 | 680 | int count = 0; |
f30432d7 | 681 | |
b35d4555 MM |
682 | finish_try_block (try_block); |
683 | handler = begin_handler (); | |
684 | blocks = finish_handler_parms (NULL_TREE, handler); | |
f30432d7 | 685 | |
1ef9f749 | 686 | if (TREE_VALUE (raises) == NULL_TREE) |
6c20b7e9 | 687 | { |
1ef9f749 JM |
688 | fn = get_identifier ("__check_null_eh_spec"); |
689 | if (IDENTIFIER_GLOBAL_VALUE (fn)) | |
690 | fn = IDENTIFIER_GLOBAL_VALUE (fn); | |
691 | else | |
692 | { | |
693 | tmp = build_function_type (void_type_node, void_list_node); | |
694 | fn = push_throw_library_fn (fn, tmp); | |
c00996a3 JM |
695 | /* Since the spec doesn't allow any exceptions, this call will |
696 | never throw. We use push_throw_library_fn because we do want | |
697 | TREE_THIS_VOLATILE to be set. */ | |
1ef9f749 JM |
698 | TREE_NOTHROW (fn) = 1; |
699 | } | |
700 | tmp = NULL_TREE; | |
6c20b7e9 | 701 | } |
1ef9f749 JM |
702 | else |
703 | { | |
704 | /* Build up an array of type_infos. */ | |
705 | for (; raises && TREE_VALUE (raises); raises = TREE_CHAIN (raises)) | |
706 | { | |
707 | types = tree_cons | |
708 | (NULL_TREE, build_eh_type_type (TREE_VALUE (raises)), types); | |
709 | ++count; | |
710 | } | |
eb66be0e | 711 | |
1ef9f749 JM |
712 | types = build_nt (CONSTRUCTOR, NULL_TREE, types); |
713 | TREE_HAS_CONSTRUCTOR (types) = 1; | |
6874c264 | 714 | |
1ef9f749 JM |
715 | /* We can't pass the CONSTRUCTOR directly, so stick it in a variable. */ |
716 | tmp = build_cplus_array_type (const_ptr_type_node, NULL_TREE); | |
717 | decl = build_decl (VAR_DECL, NULL_TREE, tmp); | |
718 | DECL_ARTIFICIAL (decl) = 1; | |
719 | DECL_INITIAL (decl) = types; | |
720 | DECL_CONTEXT (decl) = current_function_decl; | |
721 | cp_finish_decl (decl, types, NULL_TREE, 0); | |
6c20b7e9 | 722 | |
1ef9f749 | 723 | decl = decay_conversion (decl); |
6874c264 | 724 | |
1ef9f749 JM |
725 | fn = get_identifier ("__check_eh_spec"); |
726 | if (IDENTIFIER_GLOBAL_VALUE (fn)) | |
727 | fn = IDENTIFIER_GLOBAL_VALUE (fn); | |
728 | else | |
729 | { | |
730 | tmp = tree_cons | |
731 | (NULL_TREE, integer_type_node, tree_cons | |
732 | (NULL_TREE, TREE_TYPE (decl), void_list_node)); | |
733 | tmp = build_function_type (void_type_node, tmp); | |
734 | ||
735 | fn = push_throw_library_fn (fn, tmp); | |
736 | } | |
0c11ada6 | 737 | |
1ef9f749 JM |
738 | tmp = tree_cons (NULL_TREE, build_int_2 (count, 0), |
739 | tree_cons (NULL_TREE, decl, NULL_TREE)); | |
6c20b7e9 JM |
740 | } |
741 | ||
0c11ada6 | 742 | tmp = build_call (fn, tmp); |
b35d4555 | 743 | finish_expr_stmt (tmp); |
6c20b7e9 | 744 | |
b35d4555 MM |
745 | finish_handler (blocks, handler); |
746 | finish_handler_sequence (try_block); | |
f30432d7 MS |
747 | } |
748 | ||
8d2733ca MS |
749 | /* This is called to expand all the toplevel exception handling |
750 | finalization for a function. It should only be called once per | |
751 | function. */ | |
6467930b | 752 | |
8d08fdba | 753 | void |
8d2733ca | 754 | expand_exception_blocks () |
8d08fdba | 755 | { |
92b96838 | 756 | do_pending_stack_adjust (); |
eb448459 | 757 | |
e00737d2 | 758 | if (catch_clauses) |
f30432d7 | 759 | { |
e00737d2 MS |
760 | rtx funcend = gen_label_rtx (); |
761 | emit_jump (funcend); | |
762 | ||
eb66be0e MS |
763 | /* We cannot protect n regions this way if we must flow into the |
764 | EH region through the top of the region, as we have to with | |
765 | the setjmp/longjmp approach. */ | |
766 | if (exceptions_via_longjmp == 0) | |
fb98cff6 | 767 | expand_eh_region_start (); |
f30432d7 | 768 | |
e00737d2 | 769 | emit_insns (catch_clauses); |
c14f7160 | 770 | catch_clauses = catch_clauses_last = NULL_RTX; |
eb66be0e MS |
771 | |
772 | if (exceptions_via_longjmp == 0) | |
f4a23343 | 773 | expand_eh_region_end (build_terminate_handler ()); |
eb66be0e | 774 | |
4a6ef811 | 775 | emit_insns (catch_clauses); |
c14f7160 | 776 | catch_clauses = catch_clauses_last = NULL_RTX; |
e00737d2 MS |
777 | emit_label (funcend); |
778 | } | |
8d08fdba MS |
779 | } |
780 | ||
f4a23343 JM |
781 | /* Return a pointer to a buffer for an exception object of type TYPE. */ |
782 | ||
c6160f8f | 783 | static tree |
f4a23343 JM |
784 | alloc_eh_object (type) |
785 | tree type; | |
786 | { | |
787 | tree fn, exp; | |
788 | ||
789 | fn = get_identifier ("__eh_alloc"); | |
790 | if (IDENTIFIER_GLOBAL_VALUE (fn)) | |
791 | fn = IDENTIFIER_GLOBAL_VALUE (fn); | |
792 | else | |
793 | { | |
794 | /* Declare __eh_alloc (size_t), as defined in exception.cc. */ | |
0c11ada6 JM |
795 | tree tmp = tree_cons (NULL_TREE, sizetype, void_list_node); |
796 | fn = push_library_fn (fn, build_function_type (ptr_type_node, tmp)); | |
f4a23343 JM |
797 | } |
798 | ||
e1b3e07d | 799 | exp = build_function_call (fn, tree_cons |
f4a23343 JM |
800 | (NULL_TREE, size_in_bytes (type), NULL_TREE)); |
801 | exp = build1 (NOP_EXPR, build_pointer_type (type), exp); | |
802 | return exp; | |
803 | } | |
804 | ||
6467930b | 805 | /* Expand a throw statement. This follows the following |
8d2733ca MS |
806 | algorithm: |
807 | ||
808 | 1. Allocate space to save the current PC onto the stack. | |
809 | 2. Generate and emit a label and save its address into the | |
e1cd6e56 | 810 | newly allocated stack space since we can't save the pc directly. |
8d2733ca MS |
811 | 3. If this is the first call to throw in this function: |
812 | generate a label for the throw block | |
813 | 4. jump to the throw block label. */ | |
6467930b | 814 | |
225ff119 | 815 | static tree |
8d2733ca MS |
816 | expand_throw (exp) |
817 | tree exp; | |
8d08fdba | 818 | { |
6874c264 | 819 | tree fn; |
8d08fdba | 820 | |
8d2733ca | 821 | if (! doing_eh (1)) |
59ccf49d | 822 | return error_mark_node; |
8d08fdba | 823 | |
e97f22c9 TT |
824 | if (exp |
825 | && decl_is_java_type (TREE_TYPE (exp), 1)) | |
826 | { | |
827 | /* A Java `throw' statement. */ | |
828 | tree args = tree_cons (NULL_TREE, exp, NULL); | |
829 | ||
830 | fn = get_identifier (exceptions_via_longjmp | |
d9420976 | 831 | ? "_Jv_Sjlj_Throw" |
e97f22c9 TT |
832 | : "_Jv_Throw"); |
833 | if (IDENTIFIER_GLOBAL_VALUE (fn)) | |
834 | fn = IDENTIFIER_GLOBAL_VALUE (fn); | |
835 | else | |
836 | { | |
837 | /* Declare _Jv_Throw (void *), as defined in Java's | |
838 | exception.cc. */ | |
0c11ada6 JM |
839 | tree tmp = tree_cons (NULL_TREE, ptr_type_node, void_list_node); |
840 | tmp = build_function_type (ptr_type_node, tmp); | |
c00996a3 | 841 | fn = push_throw_library_fn (fn, tmp); |
e97f22c9 TT |
842 | } |
843 | ||
844 | exp = build_function_call (fn, args); | |
845 | } | |
846 | else if (exp) | |
8d2733ca | 847 | { |
faae18ab | 848 | tree throw_type; |
6874c264 | 849 | tree cleanup = NULL_TREE, e; |
59ccf49d MM |
850 | tree stmt_expr; |
851 | tree compound_stmt; | |
852 | tree try_block; | |
853 | ||
854 | begin_init_stmts (&stmt_expr, &compound_stmt); | |
faae18ab | 855 | |
a3b49ccd | 856 | /* throw expression */ |
e92cc029 | 857 | /* First, decay it. */ |
f30432d7 | 858 | exp = decay_conversion (exp); |
a3b49ccd | 859 | |
298d6f60 MM |
860 | /* The CLEANUP_TYPE is the internal type of a destructor. Under |
861 | the old ABI, destructors are two-argument functions; under | |
862 | the new ABI they take only one argument. */ | |
6874c264 | 863 | if (cleanup_type == NULL_TREE) |
298d6f60 MM |
864 | { |
865 | tree arg_types; | |
866 | ||
867 | arg_types = void_list_node; | |
868 | if (!flag_new_abi) | |
869 | arg_types = tree_cons (NULL_TREE, integer_type_node, arg_types); | |
870 | arg_types = tree_cons (NULL_TREE, ptr_type_node, arg_types); | |
871 | cleanup_type = (build_pointer_type | |
872 | (build_function_type (void_type_node, arg_types))); | |
873 | } | |
6874c264 | 874 | |
08b24bda | 875 | if (TYPE_PTR_P (TREE_TYPE (exp))) |
db48b831 | 876 | throw_type = build_eh_type_type (TREE_TYPE (exp)); |
f30432d7 MS |
877 | else |
878 | { | |
f4a23343 JM |
879 | tree object, ptr; |
880 | ||
cab1f180 | 881 | /* OK, this is kind of wacky. The standard says that we call |
46e8c075 MM |
882 | terminate when the exception handling mechanism, after |
883 | completing evaluation of the expression to be thrown but | |
884 | before the exception is caught (_except.throw_), calls a | |
885 | user function that exits via an uncaught exception. | |
f4a23343 JM |
886 | |
887 | So we have to protect the actual initialization of the | |
c00996a3 JM |
888 | exception object with terminate(), but evaluate the |
889 | expression first. Since there could be temps in the | |
890 | expression, we need to handle that, too. We also expand | |
891 | the call to __eh_alloc first (which doesn't matter, since | |
892 | it can't throw). */ | |
a50f0918 | 893 | |
f2c5f623 | 894 | my_friendly_assert (stmts_are_full_exprs_p () == 1, 19990926); |
f4a23343 | 895 | |
f4a23343 JM |
896 | /* Store the throw expression into a temp. This can be less |
897 | efficient than storing it into the allocated space directly, but | |
c00996a3 JM |
898 | if we allocated the space first we would have to deal with |
899 | cleaning it up if evaluating this expression throws. */ | |
f4a23343 JM |
900 | if (TREE_SIDE_EFFECTS (exp)) |
901 | { | |
f1dedc31 | 902 | tree temp = create_temporary_var (TREE_TYPE (exp)); |
c37dc68e | 903 | DECL_INITIAL (temp) = exp; |
cd9f6678 | 904 | cp_finish_decl (temp, exp, NULL_TREE, LOOKUP_ONLYCONVERTING); |
f4a23343 JM |
905 | exp = temp; |
906 | } | |
f4a23343 JM |
907 | |
908 | /* Allocate the space for the exception. */ | |
909 | ptr = save_expr (alloc_eh_object (TREE_TYPE (exp))); | |
59ccf49d | 910 | finish_expr_stmt (ptr); |
f4a23343 | 911 | |
59ccf49d | 912 | try_block = begin_try_block (); |
f4a23343 JM |
913 | object = build_indirect_ref (ptr, NULL_PTR); |
914 | exp = build_modify_expr (object, INIT_EXPR, exp); | |
faae18ab | 915 | |
f30432d7 | 916 | if (exp == error_mark_node) |
8251199e | 917 | error (" in thrown expression"); |
faae18ab | 918 | |
59ccf49d MM |
919 | finish_expr_stmt (exp); |
920 | finish_cleanup_try_block (try_block); | |
921 | finish_cleanup (build_terminate_handler (), try_block); | |
f4a23343 | 922 | |
db48b831 | 923 | throw_type = build_eh_type_type (TREE_TYPE (object)); |
72b7eeff | 924 | |
6874c264 JM |
925 | if (TYPE_HAS_DESTRUCTOR (TREE_TYPE (object))) |
926 | { | |
927 | cleanup = lookup_fnfields (TYPE_BINFO (TREE_TYPE (object)), | |
298d6f60 MM |
928 | (flag_new_abi |
929 | ? complete_dtor_identifier | |
930 | : dtor_identifier), | |
931 | 0); | |
6874c264 | 932 | cleanup = TREE_VALUE (cleanup); |
e872bb7a | 933 | mark_used (cleanup); |
6874c264 JM |
934 | mark_addressable (cleanup); |
935 | /* Pretend it's a normal function. */ | |
936 | cleanup = build1 (ADDR_EXPR, cleanup_type, cleanup); | |
937 | } | |
f4a23343 JM |
938 | |
939 | exp = ptr; | |
f30432d7 | 940 | } |
faae18ab | 941 | |
bbeeb2b0 MM |
942 | /* Cast EXP to `void *' so that it will match the prototype for |
943 | __cp_push_exception. */ | |
c37dc68e | 944 | exp = convert (ptr_type_node, exp); |
bbeeb2b0 | 945 | |
6874c264 JM |
946 | if (cleanup == NULL_TREE) |
947 | { | |
948 | cleanup = build_int_2 (0, 0); | |
949 | TREE_TYPE (cleanup) = cleanup_type; | |
950 | } | |
72b7eeff | 951 | |
298d6f60 | 952 | fn = cp_push_exception_identifier; |
6874c264 JM |
953 | if (IDENTIFIER_GLOBAL_VALUE (fn)) |
954 | fn = IDENTIFIER_GLOBAL_VALUE (fn); | |
955 | else | |
956 | { | |
957 | /* Declare __cp_push_exception (void*, void*, void (*)(void*, int)), | |
958 | as defined in exception.cc. */ | |
959 | tree tmp; | |
6874c264 JM |
960 | tmp = tree_cons |
961 | (NULL_TREE, ptr_type_node, tree_cons | |
962 | (NULL_TREE, ptr_type_node, tree_cons | |
963 | (NULL_TREE, cleanup_type, void_list_node))); | |
0c11ada6 | 964 | fn = push_void_library_fn (fn, tmp); |
6874c264 | 965 | } |
72b7eeff | 966 | |
e1b3e07d MM |
967 | e = tree_cons (NULL_TREE, exp, tree_cons |
968 | (NULL_TREE, throw_type, tree_cons | |
969 | (NULL_TREE, cleanup, NULL_TREE))); | |
59ccf49d MM |
970 | finish_expr_stmt (build_function_call (fn, e)); |
971 | ||
972 | exp = finish_init_stmts (stmt_expr, compound_stmt); | |
8d2733ca MS |
973 | } |
974 | else | |
a3b49ccd | 975 | { |
6874c264 JM |
976 | /* rethrow current exception; note that it's no longer caught. */ |
977 | ||
978 | tree fn = get_identifier ("__uncatch_exception"); | |
979 | if (IDENTIFIER_GLOBAL_VALUE (fn)) | |
980 | fn = IDENTIFIER_GLOBAL_VALUE (fn); | |
981 | else | |
0c11ada6 JM |
982 | /* Declare void __uncatch_exception (void) |
983 | as defined in exception.cc. */ | |
984 | fn = push_void_library_fn (fn, void_list_node); | |
6874c264 JM |
985 | |
986 | exp = build_function_call (fn, NULL_TREE); | |
a3b49ccd | 987 | } |
8d2733ca | 988 | |
59ccf49d | 989 | return exp; |
f376e137 | 990 | } |
8d2733ca MS |
991 | |
992 | /* Build a throw expression. */ | |
6467930b | 993 | |
8d2733ca MS |
994 | tree |
995 | build_throw (e) | |
996 | tree e; | |
997 | { | |
02020185 JM |
998 | if (e == error_mark_node) |
999 | return e; | |
1000 | ||
1001 | if (processing_template_decl) | |
1002 | return build_min (THROW_EXPR, void_type_node, e); | |
1003 | ||
e0f9a8bc | 1004 | if (e == null_node) |
8251199e | 1005 | cp_warning ("throwing NULL, which has integral, not pointer type"); |
980c394c NS |
1006 | |
1007 | if (e != NULL_TREE) | |
1008 | { | |
4cfbc546 NS |
1009 | if (!complete_ptr_ref_or_void_ptr_p (TREE_TYPE (e), e)) |
1010 | return error_mark_node; | |
980c394c | 1011 | } |
02020185 | 1012 | |
59ccf49d | 1013 | e = expand_throw (e); |
02020185 JM |
1014 | e = build1 (THROW_EXPR, void_type_node, e); |
1015 | TREE_SIDE_EFFECTS (e) = 1; | |
1016 | TREE_USED (e) = 1; | |
1017 | ||
8d2733ca | 1018 | return e; |
8d08fdba | 1019 | } |
4cfbc546 NS |
1020 | |
1021 | /* Make sure TYPE is complete, pointer to complete, reference to | |
1022 | complete, or pointer to cv void. Issue diagnostic on failure. | |
1023 | Return the zero on failure and non-zero on success. FROM can be | |
1024 | the expr or decl from whence TYPE came, if available. */ | |
1025 | ||
1026 | static int | |
1027 | complete_ptr_ref_or_void_ptr_p (type, from) | |
1028 | tree type; | |
1029 | tree from; | |
1030 | { | |
1031 | int is_ptr; | |
1032 | ||
1033 | /* Check complete. */ | |
1034 | type = complete_type_or_else (type, from); | |
1035 | if (!type) | |
1036 | return 0; | |
1037 | ||
1038 | /* Or a pointer or ref to one, or cv void *. */ | |
1039 | is_ptr = TREE_CODE (type) == POINTER_TYPE; | |
1040 | if (is_ptr || TREE_CODE (type) == REFERENCE_TYPE) | |
1041 | { | |
1042 | tree core = TREE_TYPE (type); | |
1043 | ||
b72801e2 | 1044 | if (is_ptr && VOID_TYPE_P (core)) |
4cfbc546 NS |
1045 | /* OK */; |
1046 | else if (!complete_type_or_else (core, from)) | |
1047 | return 0; | |
1048 | } | |
1049 | return 1; | |
1050 | } | |
1051 | ||
1660cb3a JM |
1052 | /* Returns nonzero if FN is a declaration of a standard C library |
1053 | function which is known not to throw. | |
1054 | ||
1055 | [lib.res.on.exception.handling]: None of the functions from the | |
1056 | Standard C library shall report an error by throwing an | |
1057 | exception, unless it calls a program-supplied function that | |
1058 | throws an exception. */ | |
1059 | ||
1060 | #include "cfns.h" | |
1061 | ||
1062 | int | |
1063 | nothrow_libfn_p (fn) | |
1064 | tree fn; | |
1065 | { | |
1066 | tree id; | |
1067 | ||
1068 | if (TREE_PUBLIC (fn) | |
1069 | && DECL_EXTERNAL (fn) | |
eb68cb58 | 1070 | && DECL_EXTERN_C_P (fn)) |
1660cb3a JM |
1071 | /* OK */; |
1072 | else | |
1073 | /* Can't be a C library function. */ | |
1074 | return 0; | |
1075 | ||
1076 | id = DECL_ASSEMBLER_NAME (fn); | |
1077 | return !!libc_name_p (IDENTIFIER_POINTER (id), IDENTIFIER_LENGTH (id)); | |
1078 | } | |
2bc9f1d1 JM |
1079 | |
1080 | /* Returns nonzero if an exception of type FROM will be caught by a | |
1081 | handler for type TO, as per [except.handle]. */ | |
1082 | ||
1083 | static int | |
1084 | can_convert_eh (to, from) | |
1085 | tree to, from; | |
1086 | { | |
1087 | if (TREE_CODE (to) == REFERENCE_TYPE) | |
1088 | to = TREE_TYPE (to); | |
1089 | if (TREE_CODE (from) == REFERENCE_TYPE) | |
1090 | from = TREE_TYPE (from); | |
1091 | ||
1092 | if (TREE_CODE (to) == POINTER_TYPE && TREE_CODE (from) == POINTER_TYPE) | |
1093 | { | |
1094 | to = TREE_TYPE (to); | |
1095 | from = TREE_TYPE (from); | |
1096 | ||
1097 | if (! at_least_as_qualified_p (to, from)) | |
1098 | return 0; | |
1099 | ||
1100 | if (TREE_CODE (to) == VOID_TYPE) | |
1101 | return 1; | |
1102 | ||
1103 | /* else fall through */ | |
1104 | } | |
1105 | ||
1106 | if (IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from) | |
1107 | && PUBLICLY_UNIQUELY_DERIVED_P (to, from)) | |
1108 | return 1; | |
1109 | ||
1110 | return 0; | |
1111 | } | |
1112 | ||
1113 | /* Check whether any of HANDLERS are shadowed by another handler accepting | |
1114 | TYPE. Note that the shadowing may not be complete; even if an exception | |
1115 | of type B would be caught by a handler for A, there could be a derived | |
1116 | class C for which A is an ambiguous base but B is not, so the handler | |
1117 | for B would catch an exception of type C. */ | |
1118 | ||
1119 | static void | |
1120 | check_handlers_1 (master, handlers) | |
1121 | tree master; | |
1122 | tree handlers; | |
1123 | { | |
1124 | tree type = TREE_TYPE (master); | |
1125 | tree handler; | |
1126 | ||
1127 | for (handler = handlers; handler; handler = TREE_CHAIN (handler)) | |
1128 | if (TREE_TYPE (handler) | |
1129 | && can_convert_eh (type, TREE_TYPE (handler))) | |
1130 | { | |
1131 | lineno = STMT_LINENO (handler); | |
1132 | cp_warning ("exception of type `%T' will be caught", | |
1133 | TREE_TYPE (handler)); | |
1134 | lineno = STMT_LINENO (master); | |
1135 | cp_warning (" by earlier handler for `%T'", type); | |
1136 | break; | |
1137 | } | |
1138 | } | |
1139 | ||
1140 | /* Given a chain of HANDLERs, make sure that they're OK. */ | |
1141 | ||
1142 | void | |
1143 | check_handlers (handlers) | |
1144 | tree handlers; | |
1145 | { | |
1146 | tree handler; | |
1147 | int save_line = lineno; | |
1148 | for (handler = handlers; handler; handler = TREE_CHAIN (handler)) | |
1149 | { | |
1150 | if (TREE_CHAIN (handler) == NULL_TREE) | |
1151 | /* No more handlers; nothing to shadow. */; | |
1152 | else if (TREE_TYPE (handler) == NULL_TREE) | |
1153 | { | |
1154 | lineno = STMT_LINENO (handler); | |
1155 | cp_pedwarn | |
1156 | ("`...' handler must be the last handler for its try block"); | |
1157 | } | |
1158 | else | |
1159 | check_handlers_1 (handler, TREE_CHAIN (handler)); | |
1160 | } | |
1161 | lineno = save_line; | |
1162 | } |