1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
|
/* Exception Handling interface routines.
Copyright (C) 1996 Free Software Foundation, Inc.
Contributed by Mike Stump <mrs@cygnus.com>.
This file is part of GNU CC.
GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU CC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING. If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#ifndef GET_CODE
#define rtx int *
#endif
#ifdef TREE_CODE
/* A stack of labels. CHAIN points to the next entry in the stack. */
struct label_node {
union {
rtx rlabel;
tree tlabel;
} u;
struct label_node *chain;
};
/* An eh_entry is used to describe one exception handling region.
START_LABEL is the label corresponding to the start of the region.
END_LABEL is the label corresponding to the end of the region.
EXCEPTION_HANDLER_LABEL is the label corresponding to the handler
for this region.
FINALIZATION is the tree codes for the handler, or is NULL_TREE if
one hasn't been generated yet, or is integer_zero_node to mark the
end of a group of try blocks. */
struct eh_entry {
rtx start_label;
rtx end_label;
rtx exception_handler_label;
tree finalization;
};
/* A list of EH_ENTRYs. ENTRY is the entry; CHAIN points to the next
entry in the list, or is NULL if this is the last entry. */
struct eh_node {
struct eh_entry *entry;
struct eh_node *chain;
};
/* A stack of EH_ENTRYs. TOP is the topmost entry on the stack. TOP is
NULL if the stack is empty. */
struct eh_stack {
struct eh_node *top;
};
/* A queue of EH_ENTRYs. HEAD is the front of the queue; TAIL is the
end (the latest entry). HEAD and TAIL are NULL if the queue is
empty. */
struct eh_queue {
struct eh_node *head;
struct eh_node *tail;
};
extern void expand_eh_region_start PROTO((void));
extern void expand_eh_region_end PROTO((tree));
/* Push RLABEL or TLABEL onto LABELSTACK. Only one of RLABEL or TLABEL
should be set; the other must be NULL. */
extern void push_label_entry PROTO((struct label_node **labelstack, rtx rlabel, tree tlabel));
/* Pop the topmost entry from LABELSTACK and return its value as an
rtx node. If LABELSTACK is empty, return NULL. */
extern rtx pop_label_entry PROTO((struct label_node **labelstack));
/* Return the topmost entry of LABELSTACK as a tree node, or return
NULL_TREE if LABELSTACK is empty. */
extern tree top_label_entry PROTO((struct label_node **labelstack));
/* The stack used to keep track of the exception region corresponding to
the current instruction. */
extern struct eh_stack ehstack;
/* A queue used to track closed exception regions whose handlers have
not been emitted yet. */
extern struct eh_queue ehqueue;
/* A set of insns for the catch clauses in the current function. They
will be emitted at the end of the current function. */
extern rtx catch_clauses;
#endif
struct function;
/* Toplevel initialization for EH. */
extern void init_eh PROTO((void));
/* Initialization for the per-function EH data. */
extern void init_eh_for_function PROTO((void));
/* Saves the current per-function EH data into P. */
extern void save_eh_status PROTO((struct function *p));
/* Restores the per-function EH data from P. */
extern void restore_eh_status PROTO((struct function *p));
/* Adds an EH table entry for EH entry number N. Called from
final_scan_insn for NOTE_INSN_EH_REGION_BEG. */
extern void add_eh_table_entry PROTO((int n));
/* Returns a non-zero value if we need to output an exception table. */
extern int exception_table_p PROTO((void));
/* Outputs the exception table if we have one. */
extern void output_exception_table PROTO((void));
/* Given a return address in ADDR, determine the address we should use
to find the corresponding EH region. */
extern rtx eh_outer_context PROTO((rtx addr));
/* Called at the start of a block of try statements for which there is
a supplied catch handler. */
extern void expand_start_try_stmts PROTO((void));
/* Called at the start of a block of catch statements. It terminates the
previous set of try statements. */
extern void expand_start_all_catch PROTO((void));
/* Called at the end of a block of catch statements. */
extern void expand_end_all_catch PROTO((void));
#ifdef TREE_CODE
/* Create a new exception region and add the handler for the region
onto a list. These regions will be ended (and their handlers
emitted) when end_protect_partials is invoked. */
extern void add_partial_entry PROTO((tree handler));
#endif
/* End all of the pending exception regions that have handlers added with
push_protect_entry (). */
extern void end_protect_partials PROTO((void));
/* An internal throw with a direct CONTEXT we want to throw
from. CONTEXT must be a label. */
extern void expand_internal_throw PROTO((rtx context));
/* Called from expand_exception_blocks and expand_end_catch_block to
expand and pending handlers. */
extern void expand_leftover_cleanups PROTO((void));
/* If necessary, emit insns for the start of per-function unwinder for
the current function. */
extern void emit_unwinder PROTO((void));
/* If necessary, emit insns for the end of the per-function unwinder
for the current function. */
extern void end_eh_unwinder PROTO((void));
/* Builds a list of handler labels and puts them in the global
variable exception_handler_labels. */
extern void find_exception_handler_labels PROTO((void));
/* Performs sanity checking on the check_exception_handler_labels
list. */
extern void check_exception_handler_labels PROTO((void));
/* A stack used to keep track of the label used to resume normal program
flow out of the current exception handler region. */
extern struct label_node *caught_return_label_stack;
/* A random area used for purposes elsewhere. */
extern struct label_node *false_label_stack;
/* A list of labels used for exception handlers. It is created by
find_exception_handler_labels for the optimization passes. */
extern rtx exception_handler_labels;
/* The rtx for the saved PC value. */
extern rtx eh_saved_pc_rtx;
/* Performs optimizations for exception handling, such as removing
unnecessary exception regions. Invoked from jump_optimize (). */
extern void exception_optimize PROTO((void));
|
