1 /* Exception Handling interface routines.
2 Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002
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
PARAMS ((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
PARAMS ((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
PARAMS ((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
PARAMS ((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
PARAMS ((tree
));
56 /* End a catch clause. Control will resume after the try/catch block. */
57 extern void expand_end_catch
PARAMS ((void));
59 /* End a sequence of catch handlers for a try block. */
60 extern void expand_end_all_catch
PARAMS ((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
PARAMS ((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
PARAMS ((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
PARAMS ((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
PARAMS ((tree
));
81 /* Note that the current EH region (if any) may contain a throw, or a
82 call to a function which itself may contain a throw. */
83 extern void note_eh_region_may_contain_throw
PARAMS ((void));
85 /* Invokes CALLBACK for every exception handler label. Only used by old
86 loop hackery; should not be used by new code. */
87 extern void for_each_eh_label
PARAMS ((void (*) (rtx
)));
89 /* Determine if the given INSN can throw an exception. */
90 extern bool can_throw_internal
PARAMS ((rtx
));
91 extern bool can_throw_external
PARAMS ((rtx
));
93 /* Set current_function_nothrow and cfun->all_throwers_are_sibcalls. */
94 extern void set_nothrow_function_flags
PARAMS ((void));
96 /* After initial rtl generation, call back to finish generating
97 exception support code. */
98 extern void finish_eh_generation
PARAMS ((void));
100 extern void init_eh
PARAMS ((void));
101 extern void init_eh_for_function
PARAMS ((void));
103 extern rtx reachable_handlers
PARAMS ((rtx
));
104 extern void maybe_remove_eh_handler
PARAMS ((rtx
));
106 extern void convert_from_eh_region_ranges
PARAMS ((void));
107 extern void convert_to_eh_region_ranges
PARAMS ((void));
108 extern void find_exception_handler_labels
PARAMS ((void));
109 extern bool current_function_has_exception_handlers
PARAMS ((void));
110 extern void output_function_exception_table
PARAMS ((void));
112 extern void expand_builtin_unwind_init
PARAMS ((void));
113 extern rtx expand_builtin_eh_return_data_regno
PARAMS ((tree
));
114 extern rtx expand_builtin_extract_return_addr
PARAMS ((tree
));
115 extern void expand_builtin_init_dwarf_reg_sizes
PARAMS ((tree
));
116 extern rtx expand_builtin_frob_return_addr
PARAMS ((tree
));
117 extern rtx expand_builtin_dwarf_sp_column
PARAMS ((void));
118 extern void expand_builtin_eh_return
PARAMS ((tree
, tree
));
119 extern void expand_eh_return
PARAMS ((void));
120 extern rtx get_exception_pointer
PARAMS ((struct function
*));
121 extern int duplicate_eh_regions
PARAMS ((struct function
*,
122 struct inline_remap
*));
124 extern void sjlj_emit_function_exit_after
PARAMS ((rtx
));
127 /* If non-NULL, this is a function that returns an expression to be
128 executed if an unhandled exception is propagated out of a cleanup
129 region. For example, in C++, an exception thrown by a destructor
130 during stack unwinding is required to result in a call to
131 `std::terminate', so the C++ version of this function returns a
132 CALL_EXPR for `std::terminate'. */
133 extern tree (*lang_protect_cleanup_actions
) PARAMS ((void));
135 /* Return true if type A catches type B. */
136 extern int (*lang_eh_type_covers
) PARAMS ((tree a
, tree b
));
138 /* Map a type to a runtime object to match type. */
139 extern tree (*lang_eh_runtime_type
) PARAMS ((tree
));
142 /* Just because the user configured --with-sjlj-exceptions=no doesn't
143 mean that we can use call frame exceptions. Detect that the target
144 has appropriate support. */
146 #if ! (defined (EH_RETURN_DATA_REGNO) \
147 && (defined (IA64_UNWIND_INFO) \
148 || (DWARF2_UNWIND_INFO \
149 && (defined (EH_RETURN_HANDLER_RTX) \
150 || defined (HAVE_eh_return)))))
151 #define MUST_USE_SJLJ_EXCEPTIONS 1
153 #define MUST_USE_SJLJ_EXCEPTIONS 0
156 #ifdef CONFIG_SJLJ_EXCEPTIONS
157 # if CONFIG_SJLJ_EXCEPTIONS == 1
158 # define USING_SJLJ_EXCEPTIONS 1
160 # if CONFIG_SJLJ_EXCEPTIONS == 0
161 # define USING_SJLJ_EXCEPTIONS 0
162 # ifndef EH_RETURN_DATA_REGNO
163 #error "EH_RETURN_DATA_REGNO required"
165 # if !defined(EH_RETURN_HANDLER_RTX) && !defined(HAVE_eh_return)
166 #error "EH_RETURN_HANDLER_RTX or eh_return required"
168 # if !defined(DWARF2_UNWIND_INFO) && !defined(IA64_UNWIND_INFO)
169 #error "{DWARF2,IA64}_UNWIND_INFO required"
173 # define USING_SJLJ_EXCEPTIONS MUST_USE_SJLJ_EXCEPTIONS