1 /* Exception Handling interface routines.
2 Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
3 Free Software Foundation, Inc.
4 Contributed by Mike Stump <mrs@cygnus.com>.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 2, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to the Free
20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
28 /* Per-function EH data. Used only in except.c, but GC and others
29 manipulate pointers to the opaque type. */
32 /* Internal structure describing a region. */
35 /* Test: is exception handling turned on? */
36 extern int doing_eh (int);
38 /* Start an exception handling region. All instructions emitted after
39 this point are considered to be part of the region until an
40 expand_eh_region_end variant is invoked. */
41 extern void expand_eh_region_start (void);
43 /* End an exception handling region for a cleanup. HANDLER is an
44 expression to expand for the cleanup. */
45 extern void expand_eh_region_end_cleanup (tree
);
47 /* End an exception handling region for a try block, and prepares
48 for subsequent calls to expand_start_catch. */
49 extern void expand_start_all_catch (void);
51 /* Begin a catch clause. TYPE is an object to be matched by the
52 runtime, or a list of such objects, or null if this is a catch-all
54 extern void expand_start_catch (tree
);
56 /* End a catch clause. Control will resume after the try/catch block. */
57 extern void expand_end_catch (void);
59 /* End a sequence of catch handlers for a try block. */
60 extern void expand_end_all_catch (void);
62 /* End an exception region for an exception type filter. ALLOWED is a
63 TREE_LIST of TREE_VALUE objects to be matched by the runtime.
64 FAILURE is a function to invoke if a mismatch occurs. */
65 extern void expand_eh_region_end_allowed (tree
, tree
);
67 /* End an exception region for a must-not-throw filter. FAILURE is a
68 function to invoke if an uncaught exception propagates this far. */
69 extern void expand_eh_region_end_must_not_throw (tree
);
71 /* End an exception region for a throw. No handling goes on here,
72 but it's the easiest way for the front-end to indicate what type
74 extern void expand_eh_region_end_throw (tree
);
76 /* End a fixup region. Within this region the cleanups for the immediately
77 enclosing region are _not_ run. This is used for goto cleanup to avoid
78 destroying an object twice. */
79 extern void expand_eh_region_end_fixup (tree
);
81 /* End some sort of EH region, depending on the argument. */
82 extern void expand_eh_handler (tree
);
84 /* Note that the current EH region (if any) may contain a throw, or a
85 call to a function which itself may contain a throw. */
86 extern void note_eh_region_may_contain_throw (struct eh_region
*);
87 extern void note_current_region_may_contain_throw (void);
89 /* Invokes CALLBACK for every exception handler label. Only used by old
90 loop hackery; should not be used by new code. */
91 extern void for_each_eh_label (void (*) (rtx
));
93 /* Invokes CALLBACK for every exception region in the current function. */
94 extern void for_each_eh_region (void (*) (struct eh_region
*));
96 /* Determine if the given INSN can throw an exception. */
97 extern bool can_throw_internal_1 (int);
98 extern bool can_throw_internal (rtx
);
99 extern bool can_throw_external_1 (int);
100 extern bool can_throw_external (rtx
);
102 /* Set current_function_nothrow and cfun->all_throwers_are_sibcalls. */
103 extern void set_nothrow_function_flags (void);
105 /* After initial rtl generation, call back to finish generating
106 exception support code. */
107 extern void finish_eh_generation (void);
109 extern void init_eh (void);
110 extern void init_eh_for_function (void);
112 extern rtx
reachable_handlers (rtx
);
113 extern void maybe_remove_eh_handler (rtx
);
115 extern void convert_from_eh_region_ranges (void);
116 extern void convert_to_eh_region_ranges (void);
117 extern void find_exception_handler_labels (void);
118 extern bool current_function_has_exception_handlers (void);
119 extern void output_function_exception_table (void);
121 extern void expand_builtin_unwind_init (void);
122 extern rtx
expand_builtin_eh_return_data_regno (tree
);
123 extern rtx
expand_builtin_extract_return_addr (tree
);
124 extern void expand_builtin_init_dwarf_reg_sizes (tree
);
125 extern rtx
expand_builtin_frob_return_addr (tree
);
126 extern rtx
expand_builtin_dwarf_sp_column (void);
127 extern void expand_builtin_eh_return (tree
, tree
);
128 extern void expand_eh_return (void);
129 extern rtx
expand_builtin_extend_pointer (tree
);
130 extern rtx
get_exception_pointer (struct function
*);
131 extern rtx
get_exception_filter (struct function
*);
132 extern int duplicate_eh_regions (struct function
*, struct inline_remap
*);
133 extern int check_handled (tree
, tree
);
135 extern void sjlj_emit_function_exit_after (rtx
);
137 extern struct eh_region
*gen_eh_region_cleanup (struct eh_region
*,
139 extern struct eh_region
*gen_eh_region_try (struct eh_region
*);
140 extern struct eh_region
*gen_eh_region_catch (struct eh_region
*, tree
);
141 extern struct eh_region
*gen_eh_region_allowed (struct eh_region
*, tree
);
142 extern struct eh_region
*gen_eh_region_must_not_throw (struct eh_region
*);
143 extern int get_eh_region_number (struct eh_region
*);
144 extern bool get_eh_region_may_contain_throw (struct eh_region
*);
145 extern tree
get_eh_region_tree_label (struct eh_region
*);
146 extern void set_eh_region_tree_label (struct eh_region
*, tree
);
148 extern void foreach_reachable_handler (int, bool,
149 void (*) (struct eh_region
*, void *),
152 extern void collect_eh_region_array (void);
153 extern void expand_resx_expr (tree
);
156 extern int lookup_stmt_eh_region (tree
);
158 /* If non-NULL, this is a function that returns an expression to be
159 executed if an unhandled exception is propagated out of a cleanup
160 region. For example, in C++, an exception thrown by a destructor
161 during stack unwinding is required to result in a call to
162 `std::terminate', so the C++ version of this function returns a
163 CALL_EXPR for `std::terminate'. */
164 extern tree (*lang_protect_cleanup_actions
) (void);
166 /* Return true if type A catches type B. */
167 extern int (*lang_eh_type_covers
) (tree a
, tree b
);
169 /* Map a type to a runtime object to match type. */
170 extern tree (*lang_eh_runtime_type
) (tree
);
173 /* Just because the user configured --with-sjlj-exceptions=no doesn't
174 mean that we can use call frame exceptions. Detect that the target
175 has appropriate support. */
177 #ifndef MUST_USE_SJLJ_EXCEPTIONS
178 # if !(defined (EH_RETURN_DATA_REGNO) \
179 && (defined (IA64_UNWIND_INFO) \
180 || (DWARF2_UNWIND_INFO \
181 && (defined (EH_RETURN_HANDLER_RTX) \
182 || defined (HAVE_eh_return)))))
183 # define MUST_USE_SJLJ_EXCEPTIONS 1
185 # define MUST_USE_SJLJ_EXCEPTIONS 0
189 #ifdef CONFIG_SJLJ_EXCEPTIONS
190 # if CONFIG_SJLJ_EXCEPTIONS == 1
191 # define USING_SJLJ_EXCEPTIONS 1
193 # if CONFIG_SJLJ_EXCEPTIONS == 0
194 # define USING_SJLJ_EXCEPTIONS 0
195 # ifndef EH_RETURN_DATA_REGNO
196 #error "EH_RETURN_DATA_REGNO required"
198 # if !defined(EH_RETURN_HANDLER_RTX) && !defined(HAVE_eh_return)
199 #error "EH_RETURN_HANDLER_RTX or eh_return required"
201 # if !defined(DWARF2_UNWIND_INFO) && !defined(IA64_UNWIND_INFO)
202 #error "{DWARF2,IA64}_UNWIND_INFO required"
206 # define USING_SJLJ_EXCEPTIONS MUST_USE_SJLJ_EXCEPTIONS