1 /* Exception Handling interface routines.
2 Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
3 2007, 2008 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 3, 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 COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
27 /* Per-function EH data. Used only in except.c, but GC and others
28 manipulate pointers to the opaque type. */
31 /* Internal structure describing a region. */
34 /* Test: is exception handling turned on? */
35 extern int doing_eh (int);
37 /* Note that the current EH region (if any) may contain a throw, or a
38 call to a function which itself may contain a throw. */
39 extern void note_eh_region_may_contain_throw (struct eh_region
*);
41 /* Invokes CALLBACK for every exception handler label. Only used by old
42 loop hackery; should not be used by new code. */
43 extern void for_each_eh_label (void (*) (rtx
));
45 /* Invokes CALLBACK for every exception region in the current function. */
46 extern void for_each_eh_region (void (*) (struct eh_region
*));
48 /* Determine if the given INSN can throw an exception. */
49 extern bool can_throw_internal_1 (int, bool, bool);
50 extern bool can_throw_internal (const_rtx
);
51 extern bool can_throw_external_1 (int, bool, bool);
52 extern bool can_throw_external (const_rtx
);
54 /* Set TREE_NOTHROW and cfun->all_throwers_are_sibcalls. */
55 extern unsigned int set_nothrow_function_flags (void);
57 /* After initial rtl generation, call back to finish generating
58 exception support code. */
59 extern void finish_eh_generation (void);
61 extern void init_eh (void);
62 extern void init_eh_for_function (void);
64 extern rtx
reachable_handlers (rtx
);
65 void remove_eh_region (int);
67 extern void convert_from_eh_region_ranges (void);
68 extern unsigned int convert_to_eh_region_ranges (void);
69 extern void find_exception_handler_labels (void);
70 extern bool current_function_has_exception_handlers (void);
71 extern void output_function_exception_table (const char *);
73 extern void expand_builtin_unwind_init (void);
74 extern rtx
expand_builtin_eh_return_data_regno (tree
);
75 extern rtx
expand_builtin_extract_return_addr (tree
);
76 extern void expand_builtin_init_dwarf_reg_sizes (tree
);
77 extern rtx
expand_builtin_frob_return_addr (tree
);
78 extern rtx
expand_builtin_dwarf_sp_column (void);
79 extern void expand_builtin_eh_return (tree
, tree
);
80 extern void expand_eh_return (void);
81 extern rtx
expand_builtin_extend_pointer (tree
);
82 extern rtx
get_exception_pointer (void);
83 extern rtx
get_exception_filter (void);
84 typedef tree (*duplicate_eh_regions_map
) (tree
, void *);
85 extern int duplicate_eh_regions (struct function
*, duplicate_eh_regions_map
,
88 extern void sjlj_emit_function_exit_after (rtx
);
89 extern void default_init_unwind_resume_libfunc (void);
91 extern struct eh_region
*gen_eh_region_cleanup (struct eh_region
*,
93 extern struct eh_region
*gen_eh_region_try (struct eh_region
*);
94 extern struct eh_region
*gen_eh_region_catch (struct eh_region
*, tree
);
95 extern struct eh_region
*gen_eh_region_allowed (struct eh_region
*, tree
);
96 extern struct eh_region
*gen_eh_region_must_not_throw (struct eh_region
*);
97 extern int get_eh_region_number (struct eh_region
*);
98 extern bool get_eh_region_may_contain_throw (struct eh_region
*);
99 extern tree
get_eh_region_no_tree_label (int);
100 extern tree
get_eh_region_tree_label (struct eh_region
*);
101 extern void set_eh_region_tree_label (struct eh_region
*, tree
);
103 extern void foreach_reachable_handler (int, bool, bool,
104 void (*) (struct eh_region
*, void *),
107 extern void collect_eh_region_array (void);
108 extern void expand_resx_expr (tree
);
109 extern void verify_eh_tree (struct function
*);
110 extern void dump_eh_tree (FILE *, struct function
*);
111 extern bool eh_region_outer_p (struct function
*, int, int);
112 extern int eh_region_outermost (struct function
*, int, int);
114 /* If non-NULL, this is a function that returns an expression to be
115 executed if an unhandled exception is propagated out of a cleanup
116 region. For example, in C++, an exception thrown by a destructor
117 during stack unwinding is required to result in a call to
118 `std::terminate', so the C++ version of this function returns a
119 CALL_EXPR for `std::terminate'. */
120 extern gimple (*lang_protect_cleanup_actions
) (void);
122 /* Return true if type A catches type B. */
123 extern int (*lang_eh_type_covers
) (tree a
, tree b
);
125 /* Map a type to a runtime object to match type. */
126 extern tree (*lang_eh_runtime_type
) (tree
);
129 /* Just because the user configured --with-sjlj-exceptions=no doesn't
130 mean that we can use call frame exceptions. Detect that the target
131 has appropriate support. */
133 #ifndef MUST_USE_SJLJ_EXCEPTIONS
134 # if defined (EH_RETURN_DATA_REGNO) \
135 && (defined (TARGET_UNWIND_INFO) \
136 || (DWARF2_UNWIND_INFO \
137 && (defined (EH_RETURN_HANDLER_RTX) \
138 || defined (HAVE_eh_return))))
139 # define MUST_USE_SJLJ_EXCEPTIONS 0
141 # define MUST_USE_SJLJ_EXCEPTIONS 1
145 #ifdef CONFIG_SJLJ_EXCEPTIONS
146 # if CONFIG_SJLJ_EXCEPTIONS == 1
147 # define USING_SJLJ_EXCEPTIONS 1
149 # if CONFIG_SJLJ_EXCEPTIONS == 0
150 # define USING_SJLJ_EXCEPTIONS 0
151 # if !defined(EH_RETURN_DATA_REGNO)
152 #error "EH_RETURN_DATA_REGNO required"
154 # if ! (defined(TARGET_UNWIND_INFO) || DWARF2_UNWIND_INFO)
155 #error "{DWARF2,TARGET}_UNWIND_INFO required"
157 # if !defined(TARGET_UNWIND_INFO) \
158 && !(defined(EH_RETURN_HANDLER_RTX) || defined(HAVE_eh_return))
159 #error "EH_RETURN_HANDLER_RTX or eh_return required"
161 /* Usually the above error checks will have already triggered an
162 error, but backends may set MUST_USE_SJLJ_EXCEPTIONS for their own
164 # if MUST_USE_SJLJ_EXCEPTIONS
165 #error "Must use SJLJ exceptions but configured not to"
169 # define USING_SJLJ_EXCEPTIONS MUST_USE_SJLJ_EXCEPTIONS
172 struct throw_stmt_node
GTY(())
178 extern struct htab
*get_eh_throw_stmt_table (struct function
*);
179 extern void set_eh_throw_stmt_table (struct function
*, struct htab
*);
180 extern void remove_unreachable_regions (sbitmap
, sbitmap
);
181 extern VEC(int,heap
) * label_to_region_map (void);
182 extern int num_eh_regions (void);