1 /* Implements exception handling.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005 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, 51 Franklin Street, Fifth Floor, Boston, MA
24 /* An exception is an event that can be signaled from within a
25 function. This event can then be "caught" or "trapped" by the
26 callers of this function. This potentially allows program flow to
27 be transferred to any arbitrary code associated with a function call
28 several levels up the stack.
30 The intended use for this mechanism is for signaling "exceptional
31 events" in an out-of-band fashion, hence its name. The C++ language
32 (and many other OO-styled or functional languages) practically
33 requires such a mechanism, as otherwise it becomes very difficult
34 or even impossible to signal failure conditions in complex
35 situations. The traditional C++ example is when an error occurs in
36 the process of constructing an object; without such a mechanism, it
37 is impossible to signal that the error occurs without adding global
38 state variables and error checks around every object construction.
40 The act of causing this event to occur is referred to as "throwing
41 an exception". (Alternate terms include "raising an exception" or
42 "signaling an exception".) The term "throw" is used because control
43 is returned to the callers of the function that is signaling the
44 exception, and thus there is the concept of "throwing" the
45 exception up the call stack.
47 [ Add updated documentation on how to use this. ] */
52 #include "coretypes.h"
60 #include "insn-config.h"
62 #include "integrate.h"
63 #include "hard-reg-set.h"
64 #include "basic-block.h"
66 #include "dwarf2asm.h"
67 #include "dwarf2out.h"
75 #include "langhooks.h"
77 #include "diagnostic.h"
79 /* Provide defaults for stuff that may not be defined when using
81 #ifndef EH_RETURN_DATA_REGNO
82 #define EH_RETURN_DATA_REGNO(N) INVALID_REGNUM
86 /* Protect cleanup actions with must-not-throw regions, with a call
87 to the given failure handler. */
88 tree (*lang_protect_cleanup_actions
) (void);
90 /* Return true if type A catches type B. */
91 int (*lang_eh_type_covers
) (tree a
, tree b
);
93 /* Map a type to a runtime object to match type. */
94 tree (*lang_eh_runtime_type
) (tree
);
96 /* A hash table of label to region number. */
98 struct ehl_map_entry
GTY(())
101 struct eh_region
*region
;
104 static GTY(()) int call_site_base
;
105 static GTY ((param_is (union tree_node
)))
106 htab_t type_to_runtime_map
;
108 /* Describe the SjLj_Function_Context structure. */
109 static GTY(()) tree sjlj_fc_type_node
;
110 static int sjlj_fc_call_site_ofs
;
111 static int sjlj_fc_data_ofs
;
112 static int sjlj_fc_personality_ofs
;
113 static int sjlj_fc_lsda_ofs
;
114 static int sjlj_fc_jbuf_ofs
;
116 /* Describes one exception region. */
117 struct eh_region
GTY(())
119 /* The immediately surrounding region. */
120 struct eh_region
*outer
;
122 /* The list of immediately contained regions. */
123 struct eh_region
*inner
;
124 struct eh_region
*next_peer
;
126 /* An identifier for this region. */
129 /* When a region is deleted, its parents inherit the REG_EH_REGION
130 numbers already assigned. */
133 /* Each region does exactly one thing. */
140 ERT_ALLOWED_EXCEPTIONS
,
145 /* Holds the action to perform based on the preceding type. */
147 /* A list of catch blocks, a surrounding try block,
148 and the label for continuing after a catch. */
149 struct eh_region_u_try
{
150 struct eh_region
*catch;
151 struct eh_region
*last_catch
;
152 } GTY ((tag ("ERT_TRY"))) try;
154 /* The list through the catch handlers, the list of type objects
155 matched, and the list of associated filters. */
156 struct eh_region_u_catch
{
157 struct eh_region
*next_catch
;
158 struct eh_region
*prev_catch
;
161 } GTY ((tag ("ERT_CATCH"))) catch;
163 /* A tree_list of allowed types. */
164 struct eh_region_u_allowed
{
167 } GTY ((tag ("ERT_ALLOWED_EXCEPTIONS"))) allowed
;
169 /* The type given by a call to "throw foo();", or discovered
171 struct eh_region_u_throw
{
173 } GTY ((tag ("ERT_THROW"))) throw;
175 /* Retain the cleanup expression even after expansion so that
176 we can match up fixup regions. */
177 struct eh_region_u_cleanup
{
178 struct eh_region
*prev_try
;
179 } GTY ((tag ("ERT_CLEANUP"))) cleanup
;
180 } GTY ((desc ("%0.type"))) u
;
182 /* Entry point for this region's handler before landing pads are built. */
186 /* Entry point for this region's handler from the runtime eh library. */
189 /* Entry point for this region's handler from an inner region. */
190 rtx post_landing_pad
;
192 /* The RESX insn for handing off control to the next outermost handler,
196 /* True if something in this region may throw. */
197 unsigned may_contain_throw
: 1;
200 struct call_site_record
GTY(())
206 /* Used to save exception status for each function. */
207 struct eh_status
GTY(())
209 /* The tree of all regions for this function. */
210 struct eh_region
*region_tree
;
212 /* The same information as an indexable array. */
213 struct eh_region
** GTY ((length ("%h.last_region_number"))) region_array
;
215 /* The most recently open region. */
216 struct eh_region
*cur_region
;
218 /* This is the region for which we are processing catch blocks. */
219 struct eh_region
*try_region
;
224 int built_landing_pads
;
225 int last_region_number
;
227 VEC(tree
,gc
) *ttype_data
;
228 varray_type ehspec_data
;
229 varray_type action_record_data
;
231 htab_t
GTY ((param_is (struct ehl_map_entry
))) exception_handler_label_map
;
233 struct call_site_record
* GTY ((length ("%h.call_site_data_used")))
235 int call_site_data_used
;
236 int call_site_data_size
;
245 htab_t
GTY((param_is (struct throw_stmt_node
))) throw_stmt_table
;
249 static int t2r_eq (const void *, const void *);
250 static hashval_t
t2r_hash (const void *);
251 static void add_type_for_runtime (tree
);
252 static tree
lookup_type_for_runtime (tree
);
254 static void remove_unreachable_regions (rtx
);
256 static int ttypes_filter_eq (const void *, const void *);
257 static hashval_t
ttypes_filter_hash (const void *);
258 static int ehspec_filter_eq (const void *, const void *);
259 static hashval_t
ehspec_filter_hash (const void *);
260 static int add_ttypes_entry (htab_t
, tree
);
261 static int add_ehspec_entry (htab_t
, htab_t
, tree
);
262 static void assign_filter_values (void);
263 static void build_post_landing_pads (void);
264 static void connect_post_landing_pads (void);
265 static void dw2_build_landing_pads (void);
268 static bool sjlj_find_directly_reachable_regions (struct sjlj_lp_info
*);
269 static void sjlj_assign_call_site_values (rtx
, struct sjlj_lp_info
*);
270 static void sjlj_mark_call_sites (struct sjlj_lp_info
*);
271 static void sjlj_emit_function_enter (rtx
);
272 static void sjlj_emit_function_exit (void);
273 static void sjlj_emit_dispatch_table (rtx
, struct sjlj_lp_info
*);
274 static void sjlj_build_landing_pads (void);
276 static hashval_t
ehl_hash (const void *);
277 static int ehl_eq (const void *, const void *);
278 static void add_ehl_entry (rtx
, struct eh_region
*);
279 static void remove_exception_handler_label (rtx
);
280 static void remove_eh_handler (struct eh_region
*);
281 static int for_each_eh_label_1 (void **, void *);
283 /* The return value of reachable_next_level. */
286 /* The given exception is not processed by the given region. */
288 /* The given exception may need processing by the given region. */
290 /* The given exception is completely processed by the given region. */
292 /* The given exception is completely processed by the runtime. */
296 struct reachable_info
;
297 static enum reachable_code
reachable_next_level (struct eh_region
*, tree
,
298 struct reachable_info
*);
300 static int action_record_eq (const void *, const void *);
301 static hashval_t
action_record_hash (const void *);
302 static int add_action_record (htab_t
, int, int);
303 static int collect_one_action_chain (htab_t
, struct eh_region
*);
304 static int add_call_site (rtx
, int);
306 static void push_uleb128 (varray_type
*, unsigned int);
307 static void push_sleb128 (varray_type
*, int);
308 #ifndef HAVE_AS_LEB128
309 static int dw2_size_of_call_site_table (void);
310 static int sjlj_size_of_call_site_table (void);
312 static void dw2_output_call_site_table (void);
313 static void sjlj_output_call_site_table (void);
316 /* Routine to see if exception handling is turned on.
317 DO_WARN is nonzero if we want to inform the user that exception
318 handling is turned off.
320 This is used to ensure that -fexceptions has been specified if the
321 compiler tries to use any exception-specific functions. */
324 doing_eh (int do_warn
)
326 if (! flag_exceptions
)
328 static int warned
= 0;
329 if (! warned
&& do_warn
)
331 error ("exception handling disabled, use -fexceptions to enable");
343 if (! flag_exceptions
)
346 type_to_runtime_map
= htab_create_ggc (31, t2r_hash
, t2r_eq
, NULL
);
348 /* Create the SjLj_Function_Context structure. This should match
349 the definition in unwind-sjlj.c. */
350 if (USING_SJLJ_EXCEPTIONS
)
352 tree f_jbuf
, f_per
, f_lsda
, f_prev
, f_cs
, f_data
, tmp
;
354 sjlj_fc_type_node
= lang_hooks
.types
.make_type (RECORD_TYPE
);
356 f_prev
= build_decl (FIELD_DECL
, get_identifier ("__prev"),
357 build_pointer_type (sjlj_fc_type_node
));
358 DECL_FIELD_CONTEXT (f_prev
) = sjlj_fc_type_node
;
360 f_cs
= build_decl (FIELD_DECL
, get_identifier ("__call_site"),
362 DECL_FIELD_CONTEXT (f_cs
) = sjlj_fc_type_node
;
364 tmp
= build_index_type (build_int_cst (NULL_TREE
, 4 - 1));
365 tmp
= build_array_type (lang_hooks
.types
.type_for_mode (word_mode
, 1),
367 f_data
= build_decl (FIELD_DECL
, get_identifier ("__data"), tmp
);
368 DECL_FIELD_CONTEXT (f_data
) = sjlj_fc_type_node
;
370 f_per
= build_decl (FIELD_DECL
, get_identifier ("__personality"),
372 DECL_FIELD_CONTEXT (f_per
) = sjlj_fc_type_node
;
374 f_lsda
= build_decl (FIELD_DECL
, get_identifier ("__lsda"),
376 DECL_FIELD_CONTEXT (f_lsda
) = sjlj_fc_type_node
;
378 #ifdef DONT_USE_BUILTIN_SETJMP
380 tmp
= build_int_cst (NULL_TREE
, JMP_BUF_SIZE
- 1);
382 /* Should be large enough for most systems, if it is not,
383 JMP_BUF_SIZE should be defined with the proper value. It will
384 also tend to be larger than necessary for most systems, a more
385 optimal port will define JMP_BUF_SIZE. */
386 tmp
= build_int_cst (NULL_TREE
, FIRST_PSEUDO_REGISTER
+ 2 - 1);
389 /* builtin_setjmp takes a pointer to 5 words. */
390 tmp
= build_int_cst (NULL_TREE
, 5 * BITS_PER_WORD
/ POINTER_SIZE
- 1);
392 tmp
= build_index_type (tmp
);
393 tmp
= build_array_type (ptr_type_node
, tmp
);
394 f_jbuf
= build_decl (FIELD_DECL
, get_identifier ("__jbuf"), tmp
);
395 #ifdef DONT_USE_BUILTIN_SETJMP
396 /* We don't know what the alignment requirements of the
397 runtime's jmp_buf has. Overestimate. */
398 DECL_ALIGN (f_jbuf
) = BIGGEST_ALIGNMENT
;
399 DECL_USER_ALIGN (f_jbuf
) = 1;
401 DECL_FIELD_CONTEXT (f_jbuf
) = sjlj_fc_type_node
;
403 TYPE_FIELDS (sjlj_fc_type_node
) = f_prev
;
404 TREE_CHAIN (f_prev
) = f_cs
;
405 TREE_CHAIN (f_cs
) = f_data
;
406 TREE_CHAIN (f_data
) = f_per
;
407 TREE_CHAIN (f_per
) = f_lsda
;
408 TREE_CHAIN (f_lsda
) = f_jbuf
;
410 layout_type (sjlj_fc_type_node
);
412 /* Cache the interesting field offsets so that we have
413 easy access from rtl. */
414 sjlj_fc_call_site_ofs
415 = (tree_low_cst (DECL_FIELD_OFFSET (f_cs
), 1)
416 + tree_low_cst (DECL_FIELD_BIT_OFFSET (f_cs
), 1) / BITS_PER_UNIT
);
418 = (tree_low_cst (DECL_FIELD_OFFSET (f_data
), 1)
419 + tree_low_cst (DECL_FIELD_BIT_OFFSET (f_data
), 1) / BITS_PER_UNIT
);
420 sjlj_fc_personality_ofs
421 = (tree_low_cst (DECL_FIELD_OFFSET (f_per
), 1)
422 + tree_low_cst (DECL_FIELD_BIT_OFFSET (f_per
), 1) / BITS_PER_UNIT
);
424 = (tree_low_cst (DECL_FIELD_OFFSET (f_lsda
), 1)
425 + tree_low_cst (DECL_FIELD_BIT_OFFSET (f_lsda
), 1) / BITS_PER_UNIT
);
427 = (tree_low_cst (DECL_FIELD_OFFSET (f_jbuf
), 1)
428 + tree_low_cst (DECL_FIELD_BIT_OFFSET (f_jbuf
), 1) / BITS_PER_UNIT
);
433 init_eh_for_function (void)
435 cfun
->eh
= ggc_alloc_cleared (sizeof (struct eh_status
));
438 /* Routines to generate the exception tree somewhat directly.
439 These are used from tree-eh.c when processing exception related
440 nodes during tree optimization. */
442 static struct eh_region
*
443 gen_eh_region (enum eh_region_type type
, struct eh_region
*outer
)
445 struct eh_region
*new;
447 #ifdef ENABLE_CHECKING
448 gcc_assert (doing_eh (0));
451 /* Insert a new blank region as a leaf in the tree. */
452 new = ggc_alloc_cleared (sizeof (*new));
457 new->next_peer
= outer
->inner
;
462 new->next_peer
= cfun
->eh
->region_tree
;
463 cfun
->eh
->region_tree
= new;
466 new->region_number
= ++cfun
->eh
->last_region_number
;
472 gen_eh_region_cleanup (struct eh_region
*outer
, struct eh_region
*prev_try
)
474 struct eh_region
*cleanup
= gen_eh_region (ERT_CLEANUP
, outer
);
475 cleanup
->u
.cleanup
.prev_try
= prev_try
;
480 gen_eh_region_try (struct eh_region
*outer
)
482 return gen_eh_region (ERT_TRY
, outer
);
486 gen_eh_region_catch (struct eh_region
*t
, tree type_or_list
)
488 struct eh_region
*c
, *l
;
489 tree type_list
, type_node
;
491 /* Ensure to always end up with a type list to normalize further
492 processing, then register each type against the runtime types map. */
493 type_list
= type_or_list
;
496 if (TREE_CODE (type_or_list
) != TREE_LIST
)
497 type_list
= tree_cons (NULL_TREE
, type_or_list
, NULL_TREE
);
499 type_node
= type_list
;
500 for (; type_node
; type_node
= TREE_CHAIN (type_node
))
501 add_type_for_runtime (TREE_VALUE (type_node
));
504 c
= gen_eh_region (ERT_CATCH
, t
->outer
);
505 c
->u
.catch.type_list
= type_list
;
506 l
= t
->u
.try.last_catch
;
507 c
->u
.catch.prev_catch
= l
;
509 l
->u
.catch.next_catch
= c
;
512 t
->u
.try.last_catch
= c
;
518 gen_eh_region_allowed (struct eh_region
*outer
, tree allowed
)
520 struct eh_region
*region
= gen_eh_region (ERT_ALLOWED_EXCEPTIONS
, outer
);
521 region
->u
.allowed
.type_list
= allowed
;
523 for (; allowed
; allowed
= TREE_CHAIN (allowed
))
524 add_type_for_runtime (TREE_VALUE (allowed
));
530 gen_eh_region_must_not_throw (struct eh_region
*outer
)
532 return gen_eh_region (ERT_MUST_NOT_THROW
, outer
);
536 get_eh_region_number (struct eh_region
*region
)
538 return region
->region_number
;
542 get_eh_region_may_contain_throw (struct eh_region
*region
)
544 return region
->may_contain_throw
;
548 get_eh_region_tree_label (struct eh_region
*region
)
550 return region
->tree_label
;
554 set_eh_region_tree_label (struct eh_region
*region
, tree lab
)
556 region
->tree_label
= lab
;
560 expand_resx_expr (tree exp
)
562 int region_nr
= TREE_INT_CST_LOW (TREE_OPERAND (exp
, 0));
563 struct eh_region
*reg
= cfun
->eh
->region_array
[region_nr
];
565 gcc_assert (!reg
->resume
);
566 reg
->resume
= emit_jump_insn (gen_rtx_RESX (VOIDmode
, region_nr
));
570 /* Note that the current EH region (if any) may contain a throw, or a
571 call to a function which itself may contain a throw. */
574 note_eh_region_may_contain_throw (struct eh_region
*region
)
576 while (region
&& !region
->may_contain_throw
)
578 region
->may_contain_throw
= 1;
579 region
= region
->outer
;
584 note_current_region_may_contain_throw (void)
586 note_eh_region_may_contain_throw (cfun
->eh
->cur_region
);
590 /* Return an rtl expression for a pointer to the exception object
594 get_exception_pointer (struct function
*fun
)
596 rtx exc_ptr
= fun
->eh
->exc_ptr
;
597 if (fun
== cfun
&& ! exc_ptr
)
599 exc_ptr
= gen_reg_rtx (ptr_mode
);
600 fun
->eh
->exc_ptr
= exc_ptr
;
605 /* Return an rtl expression for the exception dispatch filter
609 get_exception_filter (struct function
*fun
)
611 rtx filter
= fun
->eh
->filter
;
612 if (fun
== cfun
&& ! filter
)
614 filter
= gen_reg_rtx (targetm
.eh_return_filter_mode ());
615 fun
->eh
->filter
= filter
;
620 /* This section is for the exception handling specific optimization pass. */
622 /* Random access the exception region tree. */
625 collect_eh_region_array (void)
627 struct eh_region
**array
, *i
;
629 i
= cfun
->eh
->region_tree
;
633 array
= ggc_alloc_cleared ((cfun
->eh
->last_region_number
+ 1)
635 cfun
->eh
->region_array
= array
;
639 array
[i
->region_number
] = i
;
641 /* If there are sub-regions, process them. */
644 /* If there are peers, process them. */
645 else if (i
->next_peer
)
647 /* Otherwise, step back up the tree to the next peer. */
654 } while (i
->next_peer
== NULL
);
660 /* Remove all regions whose labels are not reachable from insns. */
663 remove_unreachable_regions (rtx insns
)
665 int i
, *uid_region_num
;
670 uid_region_num
= xcalloc (get_max_uid (), sizeof(int));
671 reachable
= xcalloc (cfun
->eh
->last_region_number
+ 1, sizeof(bool));
673 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
675 r
= cfun
->eh
->region_array
[i
];
676 if (!r
|| r
->region_number
!= i
)
681 gcc_assert (!uid_region_num
[INSN_UID (r
->resume
)]);
682 uid_region_num
[INSN_UID (r
->resume
)] = i
;
686 gcc_assert (!uid_region_num
[INSN_UID (r
->label
)]);
687 uid_region_num
[INSN_UID (r
->label
)] = i
;
691 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
692 reachable
[uid_region_num
[INSN_UID (insn
)]] = true;
694 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
696 r
= cfun
->eh
->region_array
[i
];
697 if (r
&& r
->region_number
== i
&& !reachable
[i
])
703 /* Don't remove ERT_THROW regions if their outer region
705 if (r
->outer
&& reachable
[r
->outer
->region_number
])
709 case ERT_MUST_NOT_THROW
:
710 /* MUST_NOT_THROW regions are implementable solely in the
711 runtime, but their existence continues to affect calls
712 within that region. Never delete them here. */
718 /* TRY regions are reachable if any of its CATCH regions
721 for (c
= r
->u
.try.catch; c
; c
= c
->u
.catch.next_catch
)
722 if (reachable
[c
->region_number
])
735 remove_eh_handler (r
);
740 free (uid_region_num
);
743 /* Set up EH labels for RTL. */
746 convert_from_eh_region_ranges (void)
748 rtx insns
= get_insns ();
749 int i
, n
= cfun
->eh
->last_region_number
;
751 /* Most of the work is already done at the tree level. All we need to
752 do is collect the rtl labels that correspond to the tree labels that
753 collect the rtl labels that correspond to the tree labels
754 we allocated earlier. */
755 for (i
= 1; i
<= n
; ++i
)
757 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
758 if (region
&& region
->tree_label
)
759 region
->label
= DECL_RTL_IF_SET (region
->tree_label
);
762 remove_unreachable_regions (insns
);
766 add_ehl_entry (rtx label
, struct eh_region
*region
)
768 struct ehl_map_entry
**slot
, *entry
;
770 LABEL_PRESERVE_P (label
) = 1;
772 entry
= ggc_alloc (sizeof (*entry
));
773 entry
->label
= label
;
774 entry
->region
= region
;
776 slot
= (struct ehl_map_entry
**)
777 htab_find_slot (cfun
->eh
->exception_handler_label_map
, entry
, INSERT
);
779 /* Before landing pad creation, each exception handler has its own
780 label. After landing pad creation, the exception handlers may
781 share landing pads. This is ok, since maybe_remove_eh_handler
782 only requires the 1-1 mapping before landing pad creation. */
783 gcc_assert (!*slot
|| cfun
->eh
->built_landing_pads
);
789 find_exception_handler_labels (void)
793 if (cfun
->eh
->exception_handler_label_map
)
794 htab_empty (cfun
->eh
->exception_handler_label_map
);
797 /* ??? The expansion factor here (3/2) must be greater than the htab
798 occupancy factor (4/3) to avoid unnecessary resizing. */
799 cfun
->eh
->exception_handler_label_map
800 = htab_create_ggc (cfun
->eh
->last_region_number
* 3 / 2,
801 ehl_hash
, ehl_eq
, NULL
);
804 if (cfun
->eh
->region_tree
== NULL
)
807 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
809 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
812 if (! region
|| region
->region_number
!= i
)
814 if (cfun
->eh
->built_landing_pads
)
815 lab
= region
->landing_pad
;
820 add_ehl_entry (lab
, region
);
823 /* For sjlj exceptions, need the return label to remain live until
824 after landing pad generation. */
825 if (USING_SJLJ_EXCEPTIONS
&& ! cfun
->eh
->built_landing_pads
)
826 add_ehl_entry (return_label
, NULL
);
829 /* Returns true if the current function has exception handling regions. */
832 current_function_has_exception_handlers (void)
836 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
838 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
841 && region
->region_number
== i
842 && region
->type
!= ERT_THROW
)
849 static struct eh_region
*
850 duplicate_eh_region_1 (struct eh_region
*o
)
852 struct eh_region
*n
= ggc_alloc_cleared (sizeof (struct eh_region
));
856 n
->region_number
= o
->region_number
+ cfun
->eh
->last_region_number
;
857 gcc_assert (!o
->aka
);
863 duplicate_eh_region_2 (struct eh_region
*o
, struct eh_region
**n_array
,
864 struct eh_region
*prev_try
)
866 struct eh_region
*n
= n_array
[o
->region_number
];
872 n
->u
.try.catch = n_array
[o
->u
.try.catch->region_number
];
873 if (o
->u
.try.last_catch
)
874 n
->u
.try.last_catch
= n_array
[o
->u
.try.last_catch
->region_number
];
878 if (o
->u
.catch.next_catch
)
879 n
->u
.catch.next_catch
= n_array
[o
->u
.catch.next_catch
->region_number
];
880 if (o
->u
.catch.prev_catch
)
881 n
->u
.catch.prev_catch
= n_array
[o
->u
.catch.prev_catch
->region_number
];
885 if (o
->u
.cleanup
.prev_try
)
886 n
->u
.cleanup
.prev_try
= n_array
[o
->u
.cleanup
.prev_try
->region_number
];
888 n
->u
.cleanup
.prev_try
= prev_try
;
896 n
->outer
= n_array
[o
->outer
->region_number
];
898 n
->inner
= n_array
[o
->inner
->region_number
];
900 n
->next_peer
= n_array
[o
->next_peer
->region_number
];
903 /* Duplicate the EH regions of IFUN into current function, root the tree in
904 OUTER_REGION and remap labels using MAP callback. */
906 duplicate_eh_regions (struct function
*ifun
, duplicate_eh_regions_map map
,
907 void *data
, int outer_region
)
909 int ifun_last_region_number
= ifun
->eh
->last_region_number
;
910 struct eh_region
**n_array
, *root
, *cur
, *prev_try
;
913 if (ifun_last_region_number
== 0 || !ifun
->eh
->region_tree
)
916 n_array
= xcalloc (ifun_last_region_number
+ 1, sizeof (*n_array
));
918 /* Search for the containing ERT_TRY region to fix up
919 the prev_try short-cuts for ERT_CLEANUP regions. */
921 if (outer_region
> 0)
922 for (prev_try
= cfun
->eh
->region_array
[outer_region
];
923 prev_try
&& prev_try
->type
!= ERT_TRY
;
924 prev_try
= prev_try
->outer
)
927 for (i
= 1; i
<= ifun_last_region_number
; ++i
)
929 cur
= ifun
->eh
->region_array
[i
];
930 if (!cur
|| cur
->region_number
!= i
)
932 n_array
[i
] = duplicate_eh_region_1 (cur
);
935 tree newlabel
= map (cur
->tree_label
, data
);
936 n_array
[i
]->tree_label
= newlabel
;
939 n_array
[i
]->tree_label
= NULL
;
941 for (i
= 1; i
<= ifun_last_region_number
; ++i
)
943 cur
= ifun
->eh
->region_array
[i
];
944 if (!cur
|| cur
->region_number
!= i
)
946 duplicate_eh_region_2 (cur
, n_array
, prev_try
);
949 root
= n_array
[ifun
->eh
->region_tree
->region_number
];
950 gcc_assert (root
->outer
== NULL
);
951 if (outer_region
> 0)
953 struct eh_region
*cur
= cfun
->eh
->region_array
[outer_region
];
954 struct eh_region
*p
= cur
->inner
;
964 for (i
= 1; i
<= ifun_last_region_number
; ++i
)
965 if (n_array
[i
] && n_array
[i
]->outer
== NULL
)
966 n_array
[i
]->outer
= cur
;
970 struct eh_region
*p
= cfun
->eh
->region_tree
;
978 cfun
->eh
->region_tree
= root
;
983 i
= cfun
->eh
->last_region_number
;
984 cfun
->eh
->last_region_number
= i
+ ifun_last_region_number
;
986 collect_eh_region_array ();
992 t2r_eq (const void *pentry
, const void *pdata
)
994 tree entry
= (tree
) pentry
;
995 tree data
= (tree
) pdata
;
997 return TREE_PURPOSE (entry
) == data
;
1001 t2r_hash (const void *pentry
)
1003 tree entry
= (tree
) pentry
;
1004 return TREE_HASH (TREE_PURPOSE (entry
));
1008 add_type_for_runtime (tree type
)
1012 slot
= (tree
*) htab_find_slot_with_hash (type_to_runtime_map
, type
,
1013 TREE_HASH (type
), INSERT
);
1016 tree runtime
= (*lang_eh_runtime_type
) (type
);
1017 *slot
= tree_cons (type
, runtime
, NULL_TREE
);
1022 lookup_type_for_runtime (tree type
)
1026 slot
= (tree
*) htab_find_slot_with_hash (type_to_runtime_map
, type
,
1027 TREE_HASH (type
), NO_INSERT
);
1029 /* We should have always inserted the data earlier. */
1030 return TREE_VALUE (*slot
);
1034 /* Represent an entry in @TTypes for either catch actions
1035 or exception filter actions. */
1036 struct ttypes_filter
GTY(())
1042 /* Compare ENTRY (a ttypes_filter entry in the hash table) with DATA
1043 (a tree) for a @TTypes type node we are thinking about adding. */
1046 ttypes_filter_eq (const void *pentry
, const void *pdata
)
1048 const struct ttypes_filter
*entry
= (const struct ttypes_filter
*) pentry
;
1049 tree data
= (tree
) pdata
;
1051 return entry
->t
== data
;
1055 ttypes_filter_hash (const void *pentry
)
1057 const struct ttypes_filter
*entry
= (const struct ttypes_filter
*) pentry
;
1058 return TREE_HASH (entry
->t
);
1061 /* Compare ENTRY with DATA (both struct ttypes_filter) for a @TTypes
1062 exception specification list we are thinking about adding. */
1063 /* ??? Currently we use the type lists in the order given. Someone
1064 should put these in some canonical order. */
1067 ehspec_filter_eq (const void *pentry
, const void *pdata
)
1069 const struct ttypes_filter
*entry
= (const struct ttypes_filter
*) pentry
;
1070 const struct ttypes_filter
*data
= (const struct ttypes_filter
*) pdata
;
1072 return type_list_equal (entry
->t
, data
->t
);
1075 /* Hash function for exception specification lists. */
1078 ehspec_filter_hash (const void *pentry
)
1080 const struct ttypes_filter
*entry
= (const struct ttypes_filter
*) pentry
;
1084 for (list
= entry
->t
; list
; list
= TREE_CHAIN (list
))
1085 h
= (h
<< 5) + (h
>> 27) + TREE_HASH (TREE_VALUE (list
));
1089 /* Add TYPE (which may be NULL) to cfun->eh->ttype_data, using TYPES_HASH
1090 to speed up the search. Return the filter value to be used. */
1093 add_ttypes_entry (htab_t ttypes_hash
, tree type
)
1095 struct ttypes_filter
**slot
, *n
;
1097 slot
= (struct ttypes_filter
**)
1098 htab_find_slot_with_hash (ttypes_hash
, type
, TREE_HASH (type
), INSERT
);
1100 if ((n
= *slot
) == NULL
)
1102 /* Filter value is a 1 based table index. */
1104 n
= xmalloc (sizeof (*n
));
1106 n
->filter
= VEC_length (tree
, cfun
->eh
->ttype_data
) + 1;
1109 VEC_safe_push (tree
, gc
, cfun
->eh
->ttype_data
, type
);
1115 /* Add LIST to cfun->eh->ehspec_data, using EHSPEC_HASH and TYPES_HASH
1116 to speed up the search. Return the filter value to be used. */
1119 add_ehspec_entry (htab_t ehspec_hash
, htab_t ttypes_hash
, tree list
)
1121 struct ttypes_filter
**slot
, *n
;
1122 struct ttypes_filter dummy
;
1125 slot
= (struct ttypes_filter
**)
1126 htab_find_slot (ehspec_hash
, &dummy
, INSERT
);
1128 if ((n
= *slot
) == NULL
)
1130 /* Filter value is a -1 based byte index into a uleb128 buffer. */
1132 n
= xmalloc (sizeof (*n
));
1134 n
->filter
= -(VARRAY_ACTIVE_SIZE (cfun
->eh
->ehspec_data
) + 1);
1137 /* Generate a 0 terminated list of filter values. */
1138 for (; list
; list
= TREE_CHAIN (list
))
1140 if (targetm
.arm_eabi_unwinder
)
1141 VARRAY_PUSH_TREE (cfun
->eh
->ehspec_data
, TREE_VALUE (list
));
1144 /* Look up each type in the list and encode its filter
1145 value as a uleb128. */
1146 push_uleb128 (&cfun
->eh
->ehspec_data
,
1147 add_ttypes_entry (ttypes_hash
, TREE_VALUE (list
)));
1150 if (targetm
.arm_eabi_unwinder
)
1151 VARRAY_PUSH_TREE (cfun
->eh
->ehspec_data
, NULL_TREE
);
1153 VARRAY_PUSH_UCHAR (cfun
->eh
->ehspec_data
, 0);
1159 /* Generate the action filter values to be used for CATCH and
1160 ALLOWED_EXCEPTIONS regions. When using dwarf2 exception regions,
1161 we use lots of landing pads, and so every type or list can share
1162 the same filter value, which saves table space. */
1165 assign_filter_values (void)
1168 htab_t ttypes
, ehspec
;
1170 cfun
->eh
->ttype_data
= VEC_alloc (tree
, gc
, 16);
1171 if (targetm
.arm_eabi_unwinder
)
1172 VARRAY_TREE_INIT (cfun
->eh
->ehspec_data
, 64, "ehspec_data");
1174 VARRAY_UCHAR_INIT (cfun
->eh
->ehspec_data
, 64, "ehspec_data");
1176 ttypes
= htab_create (31, ttypes_filter_hash
, ttypes_filter_eq
, free
);
1177 ehspec
= htab_create (31, ehspec_filter_hash
, ehspec_filter_eq
, free
);
1179 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1181 struct eh_region
*r
= cfun
->eh
->region_array
[i
];
1183 /* Mind we don't process a region more than once. */
1184 if (!r
|| r
->region_number
!= i
)
1190 /* Whatever type_list is (NULL or true list), we build a list
1191 of filters for the region. */
1192 r
->u
.catch.filter_list
= NULL_TREE
;
1194 if (r
->u
.catch.type_list
!= NULL
)
1196 /* Get a filter value for each of the types caught and store
1197 them in the region's dedicated list. */
1198 tree tp_node
= r
->u
.catch.type_list
;
1200 for (;tp_node
; tp_node
= TREE_CHAIN (tp_node
))
1202 int flt
= add_ttypes_entry (ttypes
, TREE_VALUE (tp_node
));
1203 tree flt_node
= build_int_cst (NULL_TREE
, flt
);
1205 r
->u
.catch.filter_list
1206 = tree_cons (NULL_TREE
, flt_node
, r
->u
.catch.filter_list
);
1211 /* Get a filter value for the NULL list also since it will need
1212 an action record anyway. */
1213 int flt
= add_ttypes_entry (ttypes
, NULL
);
1214 tree flt_node
= build_int_cst (NULL_TREE
, flt
);
1216 r
->u
.catch.filter_list
1217 = tree_cons (NULL_TREE
, flt_node
, r
->u
.catch.filter_list
);
1222 case ERT_ALLOWED_EXCEPTIONS
:
1224 = add_ehspec_entry (ehspec
, ttypes
, r
->u
.allowed
.type_list
);
1232 htab_delete (ttypes
);
1233 htab_delete (ehspec
);
1236 /* Emit SEQ into basic block just before INSN (that is assumed to be
1237 first instruction of some existing BB and return the newly
1240 emit_to_new_bb_before (rtx seq
, rtx insn
)
1247 /* If there happens to be a fallthru edge (possibly created by cleanup_cfg
1248 call), we don't want it to go into newly created landing pad or other EH
1250 for (ei
= ei_start (BLOCK_FOR_INSN (insn
)->preds
); (e
= ei_safe_edge (ei
)); )
1251 if (e
->flags
& EDGE_FALLTHRU
)
1252 force_nonfallthru (e
);
1255 last
= emit_insn_before (seq
, insn
);
1256 if (BARRIER_P (last
))
1257 last
= PREV_INSN (last
);
1258 bb
= create_basic_block (seq
, last
, BLOCK_FOR_INSN (insn
)->prev_bb
);
1259 update_bb_for_insn (bb
);
1260 bb
->flags
|= BB_SUPERBLOCK
;
1264 /* Generate the code to actually handle exceptions, which will follow the
1268 build_post_landing_pads (void)
1272 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1274 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
1277 /* Mind we don't process a region more than once. */
1278 if (!region
|| region
->region_number
!= i
)
1281 switch (region
->type
)
1284 /* ??? Collect the set of all non-overlapping catch handlers
1285 all the way up the chain until blocked by a cleanup. */
1286 /* ??? Outer try regions can share landing pads with inner
1287 try regions if the types are completely non-overlapping,
1288 and there are no intervening cleanups. */
1290 region
->post_landing_pad
= gen_label_rtx ();
1294 emit_label (region
->post_landing_pad
);
1296 /* ??? It is mighty inconvenient to call back into the
1297 switch statement generation code in expand_end_case.
1298 Rapid prototyping sez a sequence of ifs. */
1300 struct eh_region
*c
;
1301 for (c
= region
->u
.try.catch; c
; c
= c
->u
.catch.next_catch
)
1303 if (c
->u
.catch.type_list
== NULL
)
1304 emit_jump (c
->label
);
1307 /* Need for one cmp/jump per type caught. Each type
1308 list entry has a matching entry in the filter list
1309 (see assign_filter_values). */
1310 tree tp_node
= c
->u
.catch.type_list
;
1311 tree flt_node
= c
->u
.catch.filter_list
;
1315 emit_cmp_and_jump_insns
1317 GEN_INT (tree_low_cst (TREE_VALUE (flt_node
), 0)),
1319 targetm
.eh_return_filter_mode (), 0, c
->label
);
1321 tp_node
= TREE_CHAIN (tp_node
);
1322 flt_node
= TREE_CHAIN (flt_node
);
1328 /* We delay the generation of the _Unwind_Resume until we generate
1329 landing pads. We emit a marker here so as to get good control
1330 flow data in the meantime. */
1332 = emit_jump_insn (gen_rtx_RESX (VOIDmode
, region
->region_number
));
1338 emit_to_new_bb_before (seq
, region
->u
.try.catch->label
);
1342 case ERT_ALLOWED_EXCEPTIONS
:
1343 region
->post_landing_pad
= gen_label_rtx ();
1347 emit_label (region
->post_landing_pad
);
1349 emit_cmp_and_jump_insns (cfun
->eh
->filter
,
1350 GEN_INT (region
->u
.allowed
.filter
),
1352 targetm
.eh_return_filter_mode (), 0, region
->label
);
1354 /* We delay the generation of the _Unwind_Resume until we generate
1355 landing pads. We emit a marker here so as to get good control
1356 flow data in the meantime. */
1358 = emit_jump_insn (gen_rtx_RESX (VOIDmode
, region
->region_number
));
1364 emit_to_new_bb_before (seq
, region
->label
);
1368 case ERT_MUST_NOT_THROW
:
1369 region
->post_landing_pad
= region
->label
;
1374 /* Nothing to do. */
1383 /* Replace RESX patterns with jumps to the next handler if any, or calls to
1384 _Unwind_Resume otherwise. */
1387 connect_post_landing_pads (void)
1391 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1393 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
1394 struct eh_region
*outer
;
1398 /* Mind we don't process a region more than once. */
1399 if (!region
|| region
->region_number
!= i
)
1402 /* If there is no RESX, or it has been deleted by flow, there's
1403 nothing to fix up. */
1404 if (! region
->resume
|| INSN_DELETED_P (region
->resume
))
1407 /* Search for another landing pad in this function. */
1408 for (outer
= region
->outer
; outer
; outer
= outer
->outer
)
1409 if (outer
->post_landing_pad
)
1417 basic_block src
, dest
;
1419 emit_jump (outer
->post_landing_pad
);
1420 src
= BLOCK_FOR_INSN (region
->resume
);
1421 dest
= BLOCK_FOR_INSN (outer
->post_landing_pad
);
1422 while (EDGE_COUNT (src
->succs
) > 0)
1423 remove_edge (EDGE_SUCC (src
, 0));
1424 e
= make_edge (src
, dest
, 0);
1425 e
->probability
= REG_BR_PROB_BASE
;
1426 e
->count
= src
->count
;
1430 emit_library_call (unwind_resume_libfunc
, LCT_THROW
,
1431 VOIDmode
, 1, cfun
->eh
->exc_ptr
, ptr_mode
);
1433 /* What we just emitted was a throwing libcall, so it got a
1434 barrier automatically added after it. If the last insn in
1435 the libcall sequence isn't the barrier, it's because the
1436 target emits multiple insns for a call, and there are insns
1437 after the actual call insn (which are redundant and would be
1438 optimized away). The barrier is inserted exactly after the
1439 call insn, so let's go get that and delete the insns after
1440 it, because below we need the barrier to be the last insn in
1442 delete_insns_since (NEXT_INSN (last_call_insn ()));
1447 barrier
= emit_insn_before (seq
, region
->resume
);
1448 /* Avoid duplicate barrier. */
1449 gcc_assert (BARRIER_P (barrier
));
1450 delete_insn (barrier
);
1451 delete_insn (region
->resume
);
1453 /* ??? From tree-ssa we can wind up with catch regions whose
1454 label is not instantiated, but whose resx is present. Now
1455 that we've dealt with the resx, kill the region. */
1456 if (region
->label
== NULL
&& region
->type
== ERT_CLEANUP
)
1457 remove_eh_handler (region
);
1463 dw2_build_landing_pads (void)
1468 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1470 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
1473 bool clobbers_hard_regs
= false;
1476 /* Mind we don't process a region more than once. */
1477 if (!region
|| region
->region_number
!= i
)
1480 if (region
->type
!= ERT_CLEANUP
1481 && region
->type
!= ERT_TRY
1482 && region
->type
!= ERT_ALLOWED_EXCEPTIONS
)
1487 region
->landing_pad
= gen_label_rtx ();
1488 emit_label (region
->landing_pad
);
1490 #ifdef HAVE_exception_receiver
1491 if (HAVE_exception_receiver
)
1492 emit_insn (gen_exception_receiver ());
1495 #ifdef HAVE_nonlocal_goto_receiver
1496 if (HAVE_nonlocal_goto_receiver
)
1497 emit_insn (gen_nonlocal_goto_receiver ());
1502 /* If the eh_return data registers are call-saved, then we
1503 won't have considered them clobbered from the call that
1504 threw. Kill them now. */
1507 unsigned r
= EH_RETURN_DATA_REGNO (j
);
1508 if (r
== INVALID_REGNUM
)
1510 if (! call_used_regs
[r
])
1512 emit_insn (gen_rtx_CLOBBER (VOIDmode
, gen_rtx_REG (Pmode
, r
)));
1513 clobbers_hard_regs
= true;
1517 if (clobbers_hard_regs
)
1519 /* @@@ This is a kludge. Not all machine descriptions define a
1520 blockage insn, but we must not allow the code we just generated
1521 to be reordered by scheduling. So emit an ASM_INPUT to act as
1523 emit_insn (gen_rtx_ASM_INPUT (VOIDmode
, ""));
1526 emit_move_insn (cfun
->eh
->exc_ptr
,
1527 gen_rtx_REG (ptr_mode
, EH_RETURN_DATA_REGNO (0)));
1528 emit_move_insn (cfun
->eh
->filter
,
1529 gen_rtx_REG (targetm
.eh_return_filter_mode (),
1530 EH_RETURN_DATA_REGNO (1)));
1535 bb
= emit_to_new_bb_before (seq
, region
->post_landing_pad
);
1536 e
= make_edge (bb
, bb
->next_bb
, EDGE_FALLTHRU
);
1537 e
->count
= bb
->count
;
1538 e
->probability
= REG_BR_PROB_BASE
;
1545 int directly_reachable
;
1548 int call_site_index
;
1552 sjlj_find_directly_reachable_regions (struct sjlj_lp_info
*lp_info
)
1555 bool found_one
= false;
1557 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1559 struct eh_region
*region
;
1560 enum reachable_code rc
;
1564 if (! INSN_P (insn
))
1567 note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
1568 if (!note
|| INTVAL (XEXP (note
, 0)) <= 0)
1571 region
= cfun
->eh
->region_array
[INTVAL (XEXP (note
, 0))];
1573 type_thrown
= NULL_TREE
;
1574 if (region
->type
== ERT_THROW
)
1576 type_thrown
= region
->u
.throw.type
;
1577 region
= region
->outer
;
1580 /* Find the first containing region that might handle the exception.
1581 That's the landing pad to which we will transfer control. */
1582 rc
= RNL_NOT_CAUGHT
;
1583 for (; region
; region
= region
->outer
)
1585 rc
= reachable_next_level (region
, type_thrown
, NULL
);
1586 if (rc
!= RNL_NOT_CAUGHT
)
1589 if (rc
== RNL_MAYBE_CAUGHT
|| rc
== RNL_CAUGHT
)
1591 lp_info
[region
->region_number
].directly_reachable
= 1;
1600 sjlj_assign_call_site_values (rtx dispatch_label
, struct sjlj_lp_info
*lp_info
)
1605 /* First task: build the action table. */
1607 VARRAY_UCHAR_INIT (cfun
->eh
->action_record_data
, 64, "action_record_data");
1608 ar_hash
= htab_create (31, action_record_hash
, action_record_eq
, free
);
1610 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1611 if (lp_info
[i
].directly_reachable
)
1613 struct eh_region
*r
= cfun
->eh
->region_array
[i
];
1614 r
->landing_pad
= dispatch_label
;
1615 lp_info
[i
].action_index
= collect_one_action_chain (ar_hash
, r
);
1616 if (lp_info
[i
].action_index
!= -1)
1617 cfun
->uses_eh_lsda
= 1;
1620 htab_delete (ar_hash
);
1622 /* Next: assign dispatch values. In dwarf2 terms, this would be the
1623 landing pad label for the region. For sjlj though, there is one
1624 common landing pad from which we dispatch to the post-landing pads.
1626 A region receives a dispatch index if it is directly reachable
1627 and requires in-function processing. Regions that share post-landing
1628 pads may share dispatch indices. */
1629 /* ??? Post-landing pad sharing doesn't actually happen at the moment
1630 (see build_post_landing_pads) so we don't bother checking for it. */
1633 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1634 if (lp_info
[i
].directly_reachable
)
1635 lp_info
[i
].dispatch_index
= index
++;
1637 /* Finally: assign call-site values. If dwarf2 terms, this would be
1638 the region number assigned by convert_to_eh_region_ranges, but
1639 handles no-action and must-not-throw differently. */
1642 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1643 if (lp_info
[i
].directly_reachable
)
1645 int action
= lp_info
[i
].action_index
;
1647 /* Map must-not-throw to otherwise unused call-site index 0. */
1650 /* Map no-action to otherwise unused call-site index -1. */
1651 else if (action
== -1)
1653 /* Otherwise, look it up in the table. */
1655 index
= add_call_site (GEN_INT (lp_info
[i
].dispatch_index
), action
);
1657 lp_info
[i
].call_site_index
= index
;
1662 sjlj_mark_call_sites (struct sjlj_lp_info
*lp_info
)
1664 int last_call_site
= -2;
1667 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1669 struct eh_region
*region
;
1671 rtx note
, before
, p
;
1673 /* Reset value tracking at extended basic block boundaries. */
1675 last_call_site
= -2;
1677 if (! INSN_P (insn
))
1680 note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
1683 /* Calls (and trapping insns) without notes are outside any
1684 exception handling region in this function. Mark them as
1687 || (flag_non_call_exceptions
1688 && may_trap_p (PATTERN (insn
))))
1689 this_call_site
= -1;
1695 /* Calls that are known to not throw need not be marked. */
1696 if (INTVAL (XEXP (note
, 0)) <= 0)
1699 region
= cfun
->eh
->region_array
[INTVAL (XEXP (note
, 0))];
1700 this_call_site
= lp_info
[region
->region_number
].call_site_index
;
1703 if (this_call_site
== last_call_site
)
1706 /* Don't separate a call from it's argument loads. */
1709 before
= find_first_parameter_load (insn
, NULL_RTX
);
1712 mem
= adjust_address (cfun
->eh
->sjlj_fc
, TYPE_MODE (integer_type_node
),
1713 sjlj_fc_call_site_ofs
);
1714 emit_move_insn (mem
, GEN_INT (this_call_site
));
1718 emit_insn_before (p
, before
);
1719 last_call_site
= this_call_site
;
1723 /* Construct the SjLj_Function_Context. */
1726 sjlj_emit_function_enter (rtx dispatch_label
)
1728 rtx fn_begin
, fc
, mem
, seq
;
1730 fc
= cfun
->eh
->sjlj_fc
;
1734 /* We're storing this libcall's address into memory instead of
1735 calling it directly. Thus, we must call assemble_external_libcall
1736 here, as we can not depend on emit_library_call to do it for us. */
1737 assemble_external_libcall (eh_personality_libfunc
);
1738 mem
= adjust_address (fc
, Pmode
, sjlj_fc_personality_ofs
);
1739 emit_move_insn (mem
, eh_personality_libfunc
);
1741 mem
= adjust_address (fc
, Pmode
, sjlj_fc_lsda_ofs
);
1742 if (cfun
->uses_eh_lsda
)
1747 ASM_GENERATE_INTERNAL_LABEL (buf
, "LLSDA", current_function_funcdef_no
);
1748 sym
= gen_rtx_SYMBOL_REF (Pmode
, ggc_strdup (buf
));
1749 SYMBOL_REF_FLAGS (sym
) = SYMBOL_FLAG_LOCAL
;
1750 emit_move_insn (mem
, sym
);
1753 emit_move_insn (mem
, const0_rtx
);
1755 #ifdef DONT_USE_BUILTIN_SETJMP
1758 x
= emit_library_call_value (setjmp_libfunc
, NULL_RTX
, LCT_RETURNS_TWICE
,
1759 TYPE_MODE (integer_type_node
), 1,
1760 plus_constant (XEXP (fc
, 0),
1761 sjlj_fc_jbuf_ofs
), Pmode
);
1763 note
= emit_note (NOTE_INSN_EXPECTED_VALUE
);
1764 NOTE_EXPECTED_VALUE (note
) = gen_rtx_EQ (VOIDmode
, x
, const0_rtx
);
1766 emit_cmp_and_jump_insns (x
, const0_rtx
, NE
, 0,
1767 TYPE_MODE (integer_type_node
), 0, dispatch_label
);
1770 expand_builtin_setjmp_setup (plus_constant (XEXP (fc
, 0), sjlj_fc_jbuf_ofs
),
1774 emit_library_call (unwind_sjlj_register_libfunc
, LCT_NORMAL
, VOIDmode
,
1775 1, XEXP (fc
, 0), Pmode
);
1780 /* ??? Instead of doing this at the beginning of the function,
1781 do this in a block that is at loop level 0 and dominates all
1782 can_throw_internal instructions. */
1784 for (fn_begin
= get_insns (); ; fn_begin
= NEXT_INSN (fn_begin
))
1785 if (NOTE_P (fn_begin
)
1786 && (NOTE_LINE_NUMBER (fn_begin
) == NOTE_INSN_FUNCTION_BEG
1787 || NOTE_LINE_NUMBER (fn_begin
) == NOTE_INSN_BASIC_BLOCK
))
1789 if (NOTE_LINE_NUMBER (fn_begin
) == NOTE_INSN_FUNCTION_BEG
)
1790 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
1793 rtx last
= BB_END (single_succ (ENTRY_BLOCK_PTR
));
1794 for (; ; fn_begin
= NEXT_INSN (fn_begin
))
1795 if ((NOTE_P (fn_begin
)
1796 && NOTE_LINE_NUMBER (fn_begin
) == NOTE_INSN_FUNCTION_BEG
)
1797 || fn_begin
== last
)
1799 emit_insn_after (seq
, fn_begin
);
1803 /* Call back from expand_function_end to know where we should put
1804 the call to unwind_sjlj_unregister_libfunc if needed. */
1807 sjlj_emit_function_exit_after (rtx after
)
1809 cfun
->eh
->sjlj_exit_after
= after
;
1813 sjlj_emit_function_exit (void)
1821 emit_library_call (unwind_sjlj_unregister_libfunc
, LCT_NORMAL
, VOIDmode
,
1822 1, XEXP (cfun
->eh
->sjlj_fc
, 0), Pmode
);
1827 /* ??? Really this can be done in any block at loop level 0 that
1828 post-dominates all can_throw_internal instructions. This is
1829 the last possible moment. */
1831 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
1832 if (e
->flags
& EDGE_FALLTHRU
)
1838 /* Figure out whether the place we are supposed to insert libcall
1839 is inside the last basic block or after it. In the other case
1840 we need to emit to edge. */
1841 gcc_assert (e
->src
->next_bb
== EXIT_BLOCK_PTR
);
1842 for (insn
= BB_HEAD (e
->src
); ; insn
= NEXT_INSN (insn
))
1844 if (insn
== cfun
->eh
->sjlj_exit_after
)
1847 insn
= NEXT_INSN (insn
);
1848 emit_insn_after (seq
, insn
);
1851 if (insn
== BB_END (e
->src
))
1854 insert_insn_on_edge (seq
, e
);
1859 sjlj_emit_dispatch_table (rtx dispatch_label
, struct sjlj_lp_info
*lp_info
)
1861 int i
, first_reachable
;
1862 rtx mem
, dispatch
, seq
, fc
;
1867 fc
= cfun
->eh
->sjlj_fc
;
1871 emit_label (dispatch_label
);
1873 #ifndef DONT_USE_BUILTIN_SETJMP
1874 expand_builtin_setjmp_receiver (dispatch_label
);
1877 /* Load up dispatch index, exc_ptr and filter values from the
1878 function context. */
1879 mem
= adjust_address (fc
, TYPE_MODE (integer_type_node
),
1880 sjlj_fc_call_site_ofs
);
1881 dispatch
= copy_to_reg (mem
);
1883 mem
= adjust_address (fc
, word_mode
, sjlj_fc_data_ofs
);
1884 if (word_mode
!= ptr_mode
)
1886 #ifdef POINTERS_EXTEND_UNSIGNED
1887 mem
= convert_memory_address (ptr_mode
, mem
);
1889 mem
= convert_to_mode (ptr_mode
, mem
, 0);
1892 emit_move_insn (cfun
->eh
->exc_ptr
, mem
);
1894 mem
= adjust_address (fc
, word_mode
, sjlj_fc_data_ofs
+ UNITS_PER_WORD
);
1895 emit_move_insn (cfun
->eh
->filter
, mem
);
1897 /* Jump to one of the directly reachable regions. */
1898 /* ??? This really ought to be using a switch statement. */
1900 first_reachable
= 0;
1901 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1903 if (! lp_info
[i
].directly_reachable
)
1906 if (! first_reachable
)
1908 first_reachable
= i
;
1912 emit_cmp_and_jump_insns (dispatch
, GEN_INT (lp_info
[i
].dispatch_index
),
1913 EQ
, NULL_RTX
, TYPE_MODE (integer_type_node
), 0,
1914 cfun
->eh
->region_array
[i
]->post_landing_pad
);
1920 before
= cfun
->eh
->region_array
[first_reachable
]->post_landing_pad
;
1922 bb
= emit_to_new_bb_before (seq
, before
);
1923 e
= make_edge (bb
, bb
->next_bb
, EDGE_FALLTHRU
);
1924 e
->count
= bb
->count
;
1925 e
->probability
= REG_BR_PROB_BASE
;
1929 sjlj_build_landing_pads (void)
1931 struct sjlj_lp_info
*lp_info
;
1933 lp_info
= xcalloc (cfun
->eh
->last_region_number
+ 1,
1934 sizeof (struct sjlj_lp_info
));
1936 if (sjlj_find_directly_reachable_regions (lp_info
))
1938 rtx dispatch_label
= gen_label_rtx ();
1941 = assign_stack_local (TYPE_MODE (sjlj_fc_type_node
),
1942 int_size_in_bytes (sjlj_fc_type_node
),
1943 TYPE_ALIGN (sjlj_fc_type_node
));
1945 sjlj_assign_call_site_values (dispatch_label
, lp_info
);
1946 sjlj_mark_call_sites (lp_info
);
1948 sjlj_emit_function_enter (dispatch_label
);
1949 sjlj_emit_dispatch_table (dispatch_label
, lp_info
);
1950 sjlj_emit_function_exit ();
1957 finish_eh_generation (void)
1961 /* Nothing to do if no regions created. */
1962 if (cfun
->eh
->region_tree
== NULL
)
1965 /* The object here is to provide find_basic_blocks with detailed
1966 information (via reachable_handlers) on how exception control
1967 flows within the function. In this first pass, we can include
1968 type information garnered from ERT_THROW and ERT_ALLOWED_EXCEPTIONS
1969 regions, and hope that it will be useful in deleting unreachable
1970 handlers. Subsequently, we will generate landing pads which will
1971 connect many of the handlers, and then type information will not
1972 be effective. Still, this is a win over previous implementations. */
1974 /* These registers are used by the landing pads. Make sure they
1975 have been generated. */
1976 get_exception_pointer (cfun
);
1977 get_exception_filter (cfun
);
1979 /* Construct the landing pads. */
1981 assign_filter_values ();
1982 build_post_landing_pads ();
1983 connect_post_landing_pads ();
1984 if (USING_SJLJ_EXCEPTIONS
)
1985 sjlj_build_landing_pads ();
1987 dw2_build_landing_pads ();
1989 cfun
->eh
->built_landing_pads
= 1;
1991 /* We've totally changed the CFG. Start over. */
1992 find_exception_handler_labels ();
1993 break_superblocks ();
1994 if (USING_SJLJ_EXCEPTIONS
)
1995 commit_edge_insertions ();
2001 for (ei
= ei_start (bb
->succs
); (e
= ei_safe_edge (ei
)); )
2003 if (e
->flags
& EDGE_EH
)
2012 rtl_make_eh_edge (NULL
, bb
, BB_END (bb
));
2017 ehl_hash (const void *pentry
)
2019 struct ehl_map_entry
*entry
= (struct ehl_map_entry
*) pentry
;
2021 /* 2^32 * ((sqrt(5) - 1) / 2) */
2022 const hashval_t scaled_golden_ratio
= 0x9e3779b9;
2023 return CODE_LABEL_NUMBER (entry
->label
) * scaled_golden_ratio
;
2027 ehl_eq (const void *pentry
, const void *pdata
)
2029 struct ehl_map_entry
*entry
= (struct ehl_map_entry
*) pentry
;
2030 struct ehl_map_entry
*data
= (struct ehl_map_entry
*) pdata
;
2032 return entry
->label
== data
->label
;
2035 /* This section handles removing dead code for flow. */
2037 /* Remove LABEL from exception_handler_label_map. */
2040 remove_exception_handler_label (rtx label
)
2042 struct ehl_map_entry
**slot
, tmp
;
2044 /* If exception_handler_label_map was not built yet,
2045 there is nothing to do. */
2046 if (cfun
->eh
->exception_handler_label_map
== NULL
)
2050 slot
= (struct ehl_map_entry
**)
2051 htab_find_slot (cfun
->eh
->exception_handler_label_map
, &tmp
, NO_INSERT
);
2054 htab_clear_slot (cfun
->eh
->exception_handler_label_map
, (void **) slot
);
2057 /* Splice REGION from the region tree etc. */
2060 remove_eh_handler (struct eh_region
*region
)
2062 struct eh_region
**pp
, **pp_start
, *p
, *outer
, *inner
;
2065 /* For the benefit of efficiently handling REG_EH_REGION notes,
2066 replace this region in the region array with its containing
2067 region. Note that previous region deletions may result in
2068 multiple copies of this region in the array, so we have a
2069 list of alternate numbers by which we are known. */
2071 outer
= region
->outer
;
2072 cfun
->eh
->region_array
[region
->region_number
] = outer
;
2078 EXECUTE_IF_SET_IN_BITMAP (region
->aka
, 0, i
, bi
)
2080 cfun
->eh
->region_array
[i
] = outer
;
2087 outer
->aka
= BITMAP_GGC_ALLOC ();
2089 bitmap_ior_into (outer
->aka
, region
->aka
);
2090 bitmap_set_bit (outer
->aka
, region
->region_number
);
2093 if (cfun
->eh
->built_landing_pads
)
2094 lab
= region
->landing_pad
;
2096 lab
= region
->label
;
2098 remove_exception_handler_label (lab
);
2101 pp_start
= &outer
->inner
;
2103 pp_start
= &cfun
->eh
->region_tree
;
2104 for (pp
= pp_start
, p
= *pp
; p
!= region
; pp
= &p
->next_peer
, p
= *pp
)
2106 *pp
= region
->next_peer
;
2108 inner
= region
->inner
;
2111 for (p
= inner
; p
->next_peer
; p
= p
->next_peer
)
2115 p
->next_peer
= *pp_start
;
2119 if (region
->type
== ERT_CATCH
)
2121 struct eh_region
*try, *next
, *prev
;
2123 for (try = region
->next_peer
;
2124 try->type
== ERT_CATCH
;
2125 try = try->next_peer
)
2127 gcc_assert (try->type
== ERT_TRY
);
2129 next
= region
->u
.catch.next_catch
;
2130 prev
= region
->u
.catch.prev_catch
;
2133 next
->u
.catch.prev_catch
= prev
;
2135 try->u
.try.last_catch
= prev
;
2137 prev
->u
.catch.next_catch
= next
;
2140 try->u
.try.catch = next
;
2142 remove_eh_handler (try);
2147 /* LABEL heads a basic block that is about to be deleted. If this
2148 label corresponds to an exception region, we may be able to
2149 delete the region. */
2152 maybe_remove_eh_handler (rtx label
)
2154 struct ehl_map_entry
**slot
, tmp
;
2155 struct eh_region
*region
;
2157 /* ??? After generating landing pads, it's not so simple to determine
2158 if the region data is completely unused. One must examine the
2159 landing pad and the post landing pad, and whether an inner try block
2160 is referencing the catch handlers directly. */
2161 if (cfun
->eh
->built_landing_pads
)
2165 slot
= (struct ehl_map_entry
**)
2166 htab_find_slot (cfun
->eh
->exception_handler_label_map
, &tmp
, NO_INSERT
);
2169 region
= (*slot
)->region
;
2173 /* Flow will want to remove MUST_NOT_THROW regions as unreachable
2174 because there is no path to the fallback call to terminate.
2175 But the region continues to affect call-site data until there
2176 are no more contained calls, which we don't see here. */
2177 if (region
->type
== ERT_MUST_NOT_THROW
)
2179 htab_clear_slot (cfun
->eh
->exception_handler_label_map
, (void **) slot
);
2180 region
->label
= NULL_RTX
;
2183 remove_eh_handler (region
);
2186 /* Invokes CALLBACK for every exception handler label. Only used by old
2187 loop hackery; should not be used by new code. */
2190 for_each_eh_label (void (*callback
) (rtx
))
2192 htab_traverse (cfun
->eh
->exception_handler_label_map
, for_each_eh_label_1
,
2193 (void *) &callback
);
2197 for_each_eh_label_1 (void **pentry
, void *data
)
2199 struct ehl_map_entry
*entry
= *(struct ehl_map_entry
**)pentry
;
2200 void (*callback
) (rtx
) = *(void (**) (rtx
)) data
;
2202 (*callback
) (entry
->label
);
2206 /* Invoke CALLBACK for every exception region in the current function. */
2209 for_each_eh_region (void (*callback
) (struct eh_region
*))
2211 int i
, n
= cfun
->eh
->last_region_number
;
2212 for (i
= 1; i
<= n
; ++i
)
2214 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
2216 (*callback
) (region
);
2220 /* This section describes CFG exception edges for flow. */
2222 /* For communicating between calls to reachable_next_level. */
2223 struct reachable_info
2227 void (*callback
) (struct eh_region
*, void *);
2228 void *callback_data
;
2229 bool saw_any_handlers
;
2232 /* A subroutine of reachable_next_level. Return true if TYPE, or a
2233 base class of TYPE, is in HANDLED. */
2236 check_handled (tree handled
, tree type
)
2240 /* We can check for exact matches without front-end help. */
2241 if (! lang_eh_type_covers
)
2243 for (t
= handled
; t
; t
= TREE_CHAIN (t
))
2244 if (TREE_VALUE (t
) == type
)
2249 for (t
= handled
; t
; t
= TREE_CHAIN (t
))
2250 if ((*lang_eh_type_covers
) (TREE_VALUE (t
), type
))
2257 /* A subroutine of reachable_next_level. If we are collecting a list
2258 of handlers, add one. After landing pad generation, reference
2259 it instead of the handlers themselves. Further, the handlers are
2260 all wired together, so by referencing one, we've got them all.
2261 Before landing pad generation we reference each handler individually.
2263 LP_REGION contains the landing pad; REGION is the handler. */
2266 add_reachable_handler (struct reachable_info
*info
,
2267 struct eh_region
*lp_region
, struct eh_region
*region
)
2272 info
->saw_any_handlers
= true;
2274 if (cfun
->eh
->built_landing_pads
)
2275 info
->callback (lp_region
, info
->callback_data
);
2277 info
->callback (region
, info
->callback_data
);
2280 /* Process one level of exception regions for reachability.
2281 If TYPE_THROWN is non-null, then it is the *exact* type being
2282 propagated. If INFO is non-null, then collect handler labels
2283 and caught/allowed type information between invocations. */
2285 static enum reachable_code
2286 reachable_next_level (struct eh_region
*region
, tree type_thrown
,
2287 struct reachable_info
*info
)
2289 switch (region
->type
)
2292 /* Before landing-pad generation, we model control flow
2293 directly to the individual handlers. In this way we can
2294 see that catch handler types may shadow one another. */
2295 add_reachable_handler (info
, region
, region
);
2296 return RNL_MAYBE_CAUGHT
;
2300 struct eh_region
*c
;
2301 enum reachable_code ret
= RNL_NOT_CAUGHT
;
2303 for (c
= region
->u
.try.catch; c
; c
= c
->u
.catch.next_catch
)
2305 /* A catch-all handler ends the search. */
2306 if (c
->u
.catch.type_list
== NULL
)
2308 add_reachable_handler (info
, region
, c
);
2314 /* If we have at least one type match, end the search. */
2315 tree tp_node
= c
->u
.catch.type_list
;
2317 for (; tp_node
; tp_node
= TREE_CHAIN (tp_node
))
2319 tree type
= TREE_VALUE (tp_node
);
2321 if (type
== type_thrown
2322 || (lang_eh_type_covers
2323 && (*lang_eh_type_covers
) (type
, type_thrown
)))
2325 add_reachable_handler (info
, region
, c
);
2330 /* If we have definitive information of a match failure,
2331 the catch won't trigger. */
2332 if (lang_eh_type_covers
)
2333 return RNL_NOT_CAUGHT
;
2336 /* At this point, we either don't know what type is thrown or
2337 don't have front-end assistance to help deciding if it is
2338 covered by one of the types in the list for this region.
2340 We'd then like to add this region to the list of reachable
2341 handlers since it is indeed potentially reachable based on the
2342 information we have.
2344 Actually, this handler is for sure not reachable if all the
2345 types it matches have already been caught. That is, it is only
2346 potentially reachable if at least one of the types it catches
2347 has not been previously caught. */
2350 ret
= RNL_MAYBE_CAUGHT
;
2353 tree tp_node
= c
->u
.catch.type_list
;
2354 bool maybe_reachable
= false;
2356 /* Compute the potential reachability of this handler and
2357 update the list of types caught at the same time. */
2358 for (; tp_node
; tp_node
= TREE_CHAIN (tp_node
))
2360 tree type
= TREE_VALUE (tp_node
);
2362 if (! check_handled (info
->types_caught
, type
))
2365 = tree_cons (NULL
, type
, info
->types_caught
);
2367 maybe_reachable
= true;
2371 if (maybe_reachable
)
2373 add_reachable_handler (info
, region
, c
);
2375 /* ??? If the catch type is a base class of every allowed
2376 type, then we know we can stop the search. */
2377 ret
= RNL_MAYBE_CAUGHT
;
2385 case ERT_ALLOWED_EXCEPTIONS
:
2386 /* An empty list of types definitely ends the search. */
2387 if (region
->u
.allowed
.type_list
== NULL_TREE
)
2389 add_reachable_handler (info
, region
, region
);
2393 /* Collect a list of lists of allowed types for use in detecting
2394 when a catch may be transformed into a catch-all. */
2396 info
->types_allowed
= tree_cons (NULL_TREE
,
2397 region
->u
.allowed
.type_list
,
2398 info
->types_allowed
);
2400 /* If we have definitive information about the type hierarchy,
2401 then we can tell if the thrown type will pass through the
2403 if (type_thrown
&& lang_eh_type_covers
)
2405 if (check_handled (region
->u
.allowed
.type_list
, type_thrown
))
2406 return RNL_NOT_CAUGHT
;
2409 add_reachable_handler (info
, region
, region
);
2414 add_reachable_handler (info
, region
, region
);
2415 return RNL_MAYBE_CAUGHT
;
2418 /* Catch regions are handled by their controlling try region. */
2419 return RNL_NOT_CAUGHT
;
2421 case ERT_MUST_NOT_THROW
:
2422 /* Here we end our search, since no exceptions may propagate.
2423 If we've touched down at some landing pad previous, then the
2424 explicit function call we generated may be used. Otherwise
2425 the call is made by the runtime.
2427 Before inlining, do not perform this optimization. We may
2428 inline a subroutine that contains handlers, and that will
2429 change the value of saw_any_handlers. */
2431 if ((info
&& info
->saw_any_handlers
) || !cfun
->after_inlining
)
2433 add_reachable_handler (info
, region
, region
);
2441 /* Shouldn't see these here. */
2449 /* Invoke CALLBACK on each region reachable from REGION_NUMBER. */
2452 foreach_reachable_handler (int region_number
, bool is_resx
,
2453 void (*callback
) (struct eh_region
*, void *),
2454 void *callback_data
)
2456 struct reachable_info info
;
2457 struct eh_region
*region
;
2460 memset (&info
, 0, sizeof (info
));
2461 info
.callback
= callback
;
2462 info
.callback_data
= callback_data
;
2464 region
= cfun
->eh
->region_array
[region_number
];
2466 type_thrown
= NULL_TREE
;
2469 /* A RESX leaves a region instead of entering it. Thus the
2470 region itself may have been deleted out from under us. */
2473 region
= region
->outer
;
2475 else if (region
->type
== ERT_THROW
)
2477 type_thrown
= region
->u
.throw.type
;
2478 region
= region
->outer
;
2483 if (reachable_next_level (region
, type_thrown
, &info
) >= RNL_CAUGHT
)
2485 /* If we have processed one cleanup, there is no point in
2486 processing any more of them. Each cleanup will have an edge
2487 to the next outer cleanup region, so the flow graph will be
2489 if (region
->type
== ERT_CLEANUP
)
2490 region
= region
->u
.cleanup
.prev_try
;
2492 region
= region
->outer
;
2496 /* Retrieve a list of labels of exception handlers which can be
2497 reached by a given insn. */
2500 arh_to_landing_pad (struct eh_region
*region
, void *data
)
2502 rtx
*p_handlers
= data
;
2504 *p_handlers
= alloc_INSN_LIST (region
->landing_pad
, NULL_RTX
);
2508 arh_to_label (struct eh_region
*region
, void *data
)
2510 rtx
*p_handlers
= data
;
2511 *p_handlers
= alloc_INSN_LIST (region
->label
, *p_handlers
);
2515 reachable_handlers (rtx insn
)
2517 bool is_resx
= false;
2518 rtx handlers
= NULL
;
2522 && GET_CODE (PATTERN (insn
)) == RESX
)
2524 region_number
= XINT (PATTERN (insn
), 0);
2529 rtx note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
2530 if (!note
|| INTVAL (XEXP (note
, 0)) <= 0)
2532 region_number
= INTVAL (XEXP (note
, 0));
2535 foreach_reachable_handler (region_number
, is_resx
,
2536 (cfun
->eh
->built_landing_pads
2537 ? arh_to_landing_pad
2544 /* Determine if the given INSN can throw an exception that is caught
2545 within the function. */
2548 can_throw_internal_1 (int region_number
, bool is_resx
)
2550 struct eh_region
*region
;
2553 region
= cfun
->eh
->region_array
[region_number
];
2555 type_thrown
= NULL_TREE
;
2557 region
= region
->outer
;
2558 else if (region
->type
== ERT_THROW
)
2560 type_thrown
= region
->u
.throw.type
;
2561 region
= region
->outer
;
2564 /* If this exception is ignored by each and every containing region,
2565 then control passes straight out. The runtime may handle some
2566 regions, which also do not require processing internally. */
2567 for (; region
; region
= region
->outer
)
2569 enum reachable_code how
= reachable_next_level (region
, type_thrown
, 0);
2570 if (how
== RNL_BLOCKED
)
2572 if (how
!= RNL_NOT_CAUGHT
)
2580 can_throw_internal (rtx insn
)
2584 if (! INSN_P (insn
))
2588 && GET_CODE (PATTERN (insn
)) == RESX
2589 && XINT (PATTERN (insn
), 0) > 0)
2590 return can_throw_internal_1 (XINT (PATTERN (insn
), 0), true);
2592 if (NONJUMP_INSN_P (insn
)
2593 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
2594 insn
= XVECEXP (PATTERN (insn
), 0, 0);
2596 /* Every insn that might throw has an EH_REGION note. */
2597 note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
2598 if (!note
|| INTVAL (XEXP (note
, 0)) <= 0)
2601 return can_throw_internal_1 (INTVAL (XEXP (note
, 0)), false);
2604 /* Determine if the given INSN can throw an exception that is
2605 visible outside the function. */
2608 can_throw_external_1 (int region_number
, bool is_resx
)
2610 struct eh_region
*region
;
2613 region
= cfun
->eh
->region_array
[region_number
];
2615 type_thrown
= NULL_TREE
;
2617 region
= region
->outer
;
2618 else if (region
->type
== ERT_THROW
)
2620 type_thrown
= region
->u
.throw.type
;
2621 region
= region
->outer
;
2624 /* If the exception is caught or blocked by any containing region,
2625 then it is not seen by any calling function. */
2626 for (; region
; region
= region
->outer
)
2627 if (reachable_next_level (region
, type_thrown
, NULL
) >= RNL_CAUGHT
)
2634 can_throw_external (rtx insn
)
2638 if (! INSN_P (insn
))
2642 && GET_CODE (PATTERN (insn
)) == RESX
2643 && XINT (PATTERN (insn
), 0) > 0)
2644 return can_throw_external_1 (XINT (PATTERN (insn
), 0), true);
2646 if (NONJUMP_INSN_P (insn
)
2647 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
2648 insn
= XVECEXP (PATTERN (insn
), 0, 0);
2650 note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
2653 /* Calls (and trapping insns) without notes are outside any
2654 exception handling region in this function. We have to
2655 assume it might throw. Given that the front end and middle
2656 ends mark known NOTHROW functions, this isn't so wildly
2658 return (CALL_P (insn
)
2659 || (flag_non_call_exceptions
2660 && may_trap_p (PATTERN (insn
))));
2662 if (INTVAL (XEXP (note
, 0)) <= 0)
2665 return can_throw_external_1 (INTVAL (XEXP (note
, 0)), false);
2668 /* Set TREE_NOTHROW and cfun->all_throwers_are_sibcalls. */
2671 set_nothrow_function_flags (void)
2675 TREE_NOTHROW (current_function_decl
) = 1;
2677 /* Assume cfun->all_throwers_are_sibcalls until we encounter
2678 something that can throw an exception. We specifically exempt
2679 CALL_INSNs that are SIBLING_CALL_P, as these are really jumps,
2680 and can't throw. Most CALL_INSNs are not SIBLING_CALL_P, so this
2683 cfun
->all_throwers_are_sibcalls
= 1;
2685 if (! flag_exceptions
)
2688 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
2689 if (can_throw_external (insn
))
2691 TREE_NOTHROW (current_function_decl
) = 0;
2693 if (!CALL_P (insn
) || !SIBLING_CALL_P (insn
))
2695 cfun
->all_throwers_are_sibcalls
= 0;
2700 for (insn
= current_function_epilogue_delay_list
; insn
;
2701 insn
= XEXP (insn
, 1))
2702 if (can_throw_external (insn
))
2704 TREE_NOTHROW (current_function_decl
) = 0;
2706 if (!CALL_P (insn
) || !SIBLING_CALL_P (insn
))
2708 cfun
->all_throwers_are_sibcalls
= 0;
2715 /* Various hooks for unwind library. */
2717 /* Do any necessary initialization to access arbitrary stack frames.
2718 On the SPARC, this means flushing the register windows. */
2721 expand_builtin_unwind_init (void)
2723 /* Set this so all the registers get saved in our frame; we need to be
2724 able to copy the saved values for any registers from frames we unwind. */
2725 current_function_has_nonlocal_label
= 1;
2727 #ifdef SETUP_FRAME_ADDRESSES
2728 SETUP_FRAME_ADDRESSES ();
2733 expand_builtin_eh_return_data_regno (tree arglist
)
2735 tree which
= TREE_VALUE (arglist
);
2736 unsigned HOST_WIDE_INT iwhich
;
2738 if (TREE_CODE (which
) != INTEGER_CST
)
2740 error ("argument of %<__builtin_eh_return_regno%> must be constant");
2744 iwhich
= tree_low_cst (which
, 1);
2745 iwhich
= EH_RETURN_DATA_REGNO (iwhich
);
2746 if (iwhich
== INVALID_REGNUM
)
2749 #ifdef DWARF_FRAME_REGNUM
2750 iwhich
= DWARF_FRAME_REGNUM (iwhich
);
2752 iwhich
= DBX_REGISTER_NUMBER (iwhich
);
2755 return GEN_INT (iwhich
);
2758 /* Given a value extracted from the return address register or stack slot,
2759 return the actual address encoded in that value. */
2762 expand_builtin_extract_return_addr (tree addr_tree
)
2764 rtx addr
= expand_expr (addr_tree
, NULL_RTX
, Pmode
, 0);
2766 if (GET_MODE (addr
) != Pmode
2767 && GET_MODE (addr
) != VOIDmode
)
2769 #ifdef POINTERS_EXTEND_UNSIGNED
2770 addr
= convert_memory_address (Pmode
, addr
);
2772 addr
= convert_to_mode (Pmode
, addr
, 0);
2776 /* First mask out any unwanted bits. */
2777 #ifdef MASK_RETURN_ADDR
2778 expand_and (Pmode
, addr
, MASK_RETURN_ADDR
, addr
);
2781 /* Then adjust to find the real return address. */
2782 #if defined (RETURN_ADDR_OFFSET)
2783 addr
= plus_constant (addr
, RETURN_ADDR_OFFSET
);
2789 /* Given an actual address in addr_tree, do any necessary encoding
2790 and return the value to be stored in the return address register or
2791 stack slot so the epilogue will return to that address. */
2794 expand_builtin_frob_return_addr (tree addr_tree
)
2796 rtx addr
= expand_expr (addr_tree
, NULL_RTX
, ptr_mode
, 0);
2798 addr
= convert_memory_address (Pmode
, addr
);
2800 #ifdef RETURN_ADDR_OFFSET
2801 addr
= force_reg (Pmode
, addr
);
2802 addr
= plus_constant (addr
, -RETURN_ADDR_OFFSET
);
2808 /* Set up the epilogue with the magic bits we'll need to return to the
2809 exception handler. */
2812 expand_builtin_eh_return (tree stackadj_tree ATTRIBUTE_UNUSED
,
2817 #ifdef EH_RETURN_STACKADJ_RTX
2818 tmp
= expand_expr (stackadj_tree
, cfun
->eh
->ehr_stackadj
, VOIDmode
, 0);
2819 tmp
= convert_memory_address (Pmode
, tmp
);
2820 if (!cfun
->eh
->ehr_stackadj
)
2821 cfun
->eh
->ehr_stackadj
= copy_to_reg (tmp
);
2822 else if (tmp
!= cfun
->eh
->ehr_stackadj
)
2823 emit_move_insn (cfun
->eh
->ehr_stackadj
, tmp
);
2826 tmp
= expand_expr (handler_tree
, cfun
->eh
->ehr_handler
, VOIDmode
, 0);
2827 tmp
= convert_memory_address (Pmode
, tmp
);
2828 if (!cfun
->eh
->ehr_handler
)
2829 cfun
->eh
->ehr_handler
= copy_to_reg (tmp
);
2830 else if (tmp
!= cfun
->eh
->ehr_handler
)
2831 emit_move_insn (cfun
->eh
->ehr_handler
, tmp
);
2833 if (!cfun
->eh
->ehr_label
)
2834 cfun
->eh
->ehr_label
= gen_label_rtx ();
2835 emit_jump (cfun
->eh
->ehr_label
);
2839 expand_eh_return (void)
2843 if (! cfun
->eh
->ehr_label
)
2846 current_function_calls_eh_return
= 1;
2848 #ifdef EH_RETURN_STACKADJ_RTX
2849 emit_move_insn (EH_RETURN_STACKADJ_RTX
, const0_rtx
);
2852 around_label
= gen_label_rtx ();
2853 emit_jump (around_label
);
2855 emit_label (cfun
->eh
->ehr_label
);
2856 clobber_return_register ();
2858 #ifdef EH_RETURN_STACKADJ_RTX
2859 emit_move_insn (EH_RETURN_STACKADJ_RTX
, cfun
->eh
->ehr_stackadj
);
2862 #ifdef HAVE_eh_return
2864 emit_insn (gen_eh_return (cfun
->eh
->ehr_handler
));
2868 #ifdef EH_RETURN_HANDLER_RTX
2869 emit_move_insn (EH_RETURN_HANDLER_RTX
, cfun
->eh
->ehr_handler
);
2871 error ("__builtin_eh_return not supported on this target");
2875 emit_label (around_label
);
2878 /* Convert a ptr_mode address ADDR_TREE to a Pmode address controlled by
2879 POINTERS_EXTEND_UNSIGNED and return it. */
2882 expand_builtin_extend_pointer (tree addr_tree
)
2884 rtx addr
= expand_expr (addr_tree
, NULL_RTX
, ptr_mode
, 0);
2887 #ifdef POINTERS_EXTEND_UNSIGNED
2888 extend
= POINTERS_EXTEND_UNSIGNED
;
2890 /* The previous EH code did an unsigned extend by default, so we do this also
2895 return convert_modes (word_mode
, ptr_mode
, addr
, extend
);
2898 /* In the following functions, we represent entries in the action table
2899 as 1-based indices. Special cases are:
2901 0: null action record, non-null landing pad; implies cleanups
2902 -1: null action record, null landing pad; implies no action
2903 -2: no call-site entry; implies must_not_throw
2904 -3: we have yet to process outer regions
2906 Further, no special cases apply to the "next" field of the record.
2907 For next, 0 means end of list. */
2909 struct action_record
2917 action_record_eq (const void *pentry
, const void *pdata
)
2919 const struct action_record
*entry
= (const struct action_record
*) pentry
;
2920 const struct action_record
*data
= (const struct action_record
*) pdata
;
2921 return entry
->filter
== data
->filter
&& entry
->next
== data
->next
;
2925 action_record_hash (const void *pentry
)
2927 const struct action_record
*entry
= (const struct action_record
*) pentry
;
2928 return entry
->next
* 1009 + entry
->filter
;
2932 add_action_record (htab_t ar_hash
, int filter
, int next
)
2934 struct action_record
**slot
, *new, tmp
;
2936 tmp
.filter
= filter
;
2938 slot
= (struct action_record
**) htab_find_slot (ar_hash
, &tmp
, INSERT
);
2940 if ((new = *slot
) == NULL
)
2942 new = xmalloc (sizeof (*new));
2943 new->offset
= VARRAY_ACTIVE_SIZE (cfun
->eh
->action_record_data
) + 1;
2944 new->filter
= filter
;
2948 /* The filter value goes in untouched. The link to the next
2949 record is a "self-relative" byte offset, or zero to indicate
2950 that there is no next record. So convert the absolute 1 based
2951 indices we've been carrying around into a displacement. */
2953 push_sleb128 (&cfun
->eh
->action_record_data
, filter
);
2955 next
-= VARRAY_ACTIVE_SIZE (cfun
->eh
->action_record_data
) + 1;
2956 push_sleb128 (&cfun
->eh
->action_record_data
, next
);
2963 collect_one_action_chain (htab_t ar_hash
, struct eh_region
*region
)
2965 struct eh_region
*c
;
2968 /* If we've reached the top of the region chain, then we have
2969 no actions, and require no landing pad. */
2973 switch (region
->type
)
2976 /* A cleanup adds a zero filter to the beginning of the chain, but
2977 there are special cases to look out for. If there are *only*
2978 cleanups along a path, then it compresses to a zero action.
2979 Further, if there are multiple cleanups along a path, we only
2980 need to represent one of them, as that is enough to trigger
2981 entry to the landing pad at runtime. */
2982 next
= collect_one_action_chain (ar_hash
, region
->outer
);
2985 for (c
= region
->outer
; c
; c
= c
->outer
)
2986 if (c
->type
== ERT_CLEANUP
)
2988 return add_action_record (ar_hash
, 0, next
);
2991 /* Process the associated catch regions in reverse order.
2992 If there's a catch-all handler, then we don't need to
2993 search outer regions. Use a magic -3 value to record
2994 that we haven't done the outer search. */
2996 for (c
= region
->u
.try.last_catch
; c
; c
= c
->u
.catch.prev_catch
)
2998 if (c
->u
.catch.type_list
== NULL
)
3000 /* Retrieve the filter from the head of the filter list
3001 where we have stored it (see assign_filter_values). */
3003 = TREE_INT_CST_LOW (TREE_VALUE (c
->u
.catch.filter_list
));
3005 next
= add_action_record (ar_hash
, filter
, 0);
3009 /* Once the outer search is done, trigger an action record for
3010 each filter we have. */
3015 next
= collect_one_action_chain (ar_hash
, region
->outer
);
3017 /* If there is no next action, terminate the chain. */
3020 /* If all outer actions are cleanups or must_not_throw,
3021 we'll have no action record for it, since we had wanted
3022 to encode these states in the call-site record directly.
3023 Add a cleanup action to the chain to catch these. */
3025 next
= add_action_record (ar_hash
, 0, 0);
3028 flt_node
= c
->u
.catch.filter_list
;
3029 for (; flt_node
; flt_node
= TREE_CHAIN (flt_node
))
3031 int filter
= TREE_INT_CST_LOW (TREE_VALUE (flt_node
));
3032 next
= add_action_record (ar_hash
, filter
, next
);
3038 case ERT_ALLOWED_EXCEPTIONS
:
3039 /* An exception specification adds its filter to the
3040 beginning of the chain. */
3041 next
= collect_one_action_chain (ar_hash
, region
->outer
);
3043 /* If there is no next action, terminate the chain. */
3046 /* If all outer actions are cleanups or must_not_throw,
3047 we'll have no action record for it, since we had wanted
3048 to encode these states in the call-site record directly.
3049 Add a cleanup action to the chain to catch these. */
3051 next
= add_action_record (ar_hash
, 0, 0);
3053 return add_action_record (ar_hash
, region
->u
.allowed
.filter
, next
);
3055 case ERT_MUST_NOT_THROW
:
3056 /* A must-not-throw region with no inner handlers or cleanups
3057 requires no call-site entry. Note that this differs from
3058 the no handler or cleanup case in that we do require an lsda
3059 to be generated. Return a magic -2 value to record this. */
3064 /* CATCH regions are handled in TRY above. THROW regions are
3065 for optimization information only and produce no output. */
3066 return collect_one_action_chain (ar_hash
, region
->outer
);
3074 add_call_site (rtx landing_pad
, int action
)
3076 struct call_site_record
*data
= cfun
->eh
->call_site_data
;
3077 int used
= cfun
->eh
->call_site_data_used
;
3078 int size
= cfun
->eh
->call_site_data_size
;
3082 size
= (size
? size
* 2 : 64);
3083 data
= ggc_realloc (data
, sizeof (*data
) * size
);
3084 cfun
->eh
->call_site_data
= data
;
3085 cfun
->eh
->call_site_data_size
= size
;
3088 data
[used
].landing_pad
= landing_pad
;
3089 data
[used
].action
= action
;
3091 cfun
->eh
->call_site_data_used
= used
+ 1;
3093 return used
+ call_site_base
;
3096 /* Turn REG_EH_REGION notes back into NOTE_INSN_EH_REGION notes.
3097 The new note numbers will not refer to region numbers, but
3098 instead to call site entries. */
3101 convert_to_eh_region_ranges (void)
3103 rtx insn
, iter
, note
;
3105 int last_action
= -3;
3106 rtx last_action_insn
= NULL_RTX
;
3107 rtx last_landing_pad
= NULL_RTX
;
3108 rtx first_no_action_insn
= NULL_RTX
;
3111 if (USING_SJLJ_EXCEPTIONS
|| cfun
->eh
->region_tree
== NULL
)
3114 VARRAY_UCHAR_INIT (cfun
->eh
->action_record_data
, 64, "action_record_data");
3116 ar_hash
= htab_create (31, action_record_hash
, action_record_eq
, free
);
3118 for (iter
= get_insns (); iter
; iter
= NEXT_INSN (iter
))
3121 struct eh_region
*region
;
3123 rtx this_landing_pad
;
3126 if (NONJUMP_INSN_P (insn
)
3127 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
3128 insn
= XVECEXP (PATTERN (insn
), 0, 0);
3130 note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
3133 if (! (CALL_P (insn
)
3134 || (flag_non_call_exceptions
3135 && may_trap_p (PATTERN (insn
)))))
3142 if (INTVAL (XEXP (note
, 0)) <= 0)
3144 region
= cfun
->eh
->region_array
[INTVAL (XEXP (note
, 0))];
3145 this_action
= collect_one_action_chain (ar_hash
, region
);
3148 /* Existence of catch handlers, or must-not-throw regions
3149 implies that an lsda is needed (even if empty). */
3150 if (this_action
!= -1)
3151 cfun
->uses_eh_lsda
= 1;
3153 /* Delay creation of region notes for no-action regions
3154 until we're sure that an lsda will be required. */
3155 else if (last_action
== -3)
3157 first_no_action_insn
= iter
;
3161 /* Cleanups and handlers may share action chains but not
3162 landing pads. Collect the landing pad for this region. */
3163 if (this_action
>= 0)
3165 struct eh_region
*o
;
3166 for (o
= region
; ! o
->landing_pad
; o
= o
->outer
)
3168 this_landing_pad
= o
->landing_pad
;
3171 this_landing_pad
= NULL_RTX
;
3173 /* Differing actions or landing pads implies a change in call-site
3174 info, which implies some EH_REGION note should be emitted. */
3175 if (last_action
!= this_action
3176 || last_landing_pad
!= this_landing_pad
)
3178 /* If we'd not seen a previous action (-3) or the previous
3179 action was must-not-throw (-2), then we do not need an
3181 if (last_action
>= -1)
3183 /* If we delayed the creation of the begin, do it now. */
3184 if (first_no_action_insn
)
3186 call_site
= add_call_site (NULL_RTX
, 0);
3187 note
= emit_note_before (NOTE_INSN_EH_REGION_BEG
,
3188 first_no_action_insn
);
3189 NOTE_EH_HANDLER (note
) = call_site
;
3190 first_no_action_insn
= NULL_RTX
;
3193 note
= emit_note_after (NOTE_INSN_EH_REGION_END
,
3195 NOTE_EH_HANDLER (note
) = call_site
;
3198 /* If the new action is must-not-throw, then no region notes
3200 if (this_action
>= -1)
3202 call_site
= add_call_site (this_landing_pad
,
3203 this_action
< 0 ? 0 : this_action
);
3204 note
= emit_note_before (NOTE_INSN_EH_REGION_BEG
, iter
);
3205 NOTE_EH_HANDLER (note
) = call_site
;
3208 last_action
= this_action
;
3209 last_landing_pad
= this_landing_pad
;
3211 last_action_insn
= iter
;
3214 if (last_action
>= -1 && ! first_no_action_insn
)
3216 note
= emit_note_after (NOTE_INSN_EH_REGION_END
, last_action_insn
);
3217 NOTE_EH_HANDLER (note
) = call_site
;
3220 htab_delete (ar_hash
);
3225 push_uleb128 (varray_type
*data_area
, unsigned int value
)
3229 unsigned char byte
= value
& 0x7f;
3233 VARRAY_PUSH_UCHAR (*data_area
, byte
);
3239 push_sleb128 (varray_type
*data_area
, int value
)
3246 byte
= value
& 0x7f;
3248 more
= ! ((value
== 0 && (byte
& 0x40) == 0)
3249 || (value
== -1 && (byte
& 0x40) != 0));
3252 VARRAY_PUSH_UCHAR (*data_area
, byte
);
3258 #ifndef HAVE_AS_LEB128
3260 dw2_size_of_call_site_table (void)
3262 int n
= cfun
->eh
->call_site_data_used
;
3263 int size
= n
* (4 + 4 + 4);
3266 for (i
= 0; i
< n
; ++i
)
3268 struct call_site_record
*cs
= &cfun
->eh
->call_site_data
[i
];
3269 size
+= size_of_uleb128 (cs
->action
);
3276 sjlj_size_of_call_site_table (void)
3278 int n
= cfun
->eh
->call_site_data_used
;
3282 for (i
= 0; i
< n
; ++i
)
3284 struct call_site_record
*cs
= &cfun
->eh
->call_site_data
[i
];
3285 size
+= size_of_uleb128 (INTVAL (cs
->landing_pad
));
3286 size
+= size_of_uleb128 (cs
->action
);
3294 dw2_output_call_site_table (void)
3296 int n
= cfun
->eh
->call_site_data_used
;
3299 for (i
= 0; i
< n
; ++i
)
3301 struct call_site_record
*cs
= &cfun
->eh
->call_site_data
[i
];
3302 char reg_start_lab
[32];
3303 char reg_end_lab
[32];
3304 char landing_pad_lab
[32];
3306 ASM_GENERATE_INTERNAL_LABEL (reg_start_lab
, "LEHB", call_site_base
+ i
);
3307 ASM_GENERATE_INTERNAL_LABEL (reg_end_lab
, "LEHE", call_site_base
+ i
);
3309 if (cs
->landing_pad
)
3310 ASM_GENERATE_INTERNAL_LABEL (landing_pad_lab
, "L",
3311 CODE_LABEL_NUMBER (cs
->landing_pad
));
3313 /* ??? Perhaps use insn length scaling if the assembler supports
3314 generic arithmetic. */
3315 /* ??? Perhaps use attr_length to choose data1 or data2 instead of
3316 data4 if the function is small enough. */
3317 #ifdef HAVE_AS_LEB128
3318 dw2_asm_output_delta_uleb128 (reg_start_lab
,
3319 current_function_func_begin_label
,
3320 "region %d start", i
);
3321 dw2_asm_output_delta_uleb128 (reg_end_lab
, reg_start_lab
,
3323 if (cs
->landing_pad
)
3324 dw2_asm_output_delta_uleb128 (landing_pad_lab
,
3325 current_function_func_begin_label
,
3328 dw2_asm_output_data_uleb128 (0, "landing pad");
3330 dw2_asm_output_delta (4, reg_start_lab
,
3331 current_function_func_begin_label
,
3332 "region %d start", i
);
3333 dw2_asm_output_delta (4, reg_end_lab
, reg_start_lab
, "length");
3334 if (cs
->landing_pad
)
3335 dw2_asm_output_delta (4, landing_pad_lab
,
3336 current_function_func_begin_label
,
3339 dw2_asm_output_data (4, 0, "landing pad");
3341 dw2_asm_output_data_uleb128 (cs
->action
, "action");
3344 call_site_base
+= n
;
3348 sjlj_output_call_site_table (void)
3350 int n
= cfun
->eh
->call_site_data_used
;
3353 for (i
= 0; i
< n
; ++i
)
3355 struct call_site_record
*cs
= &cfun
->eh
->call_site_data
[i
];
3357 dw2_asm_output_data_uleb128 (INTVAL (cs
->landing_pad
),
3358 "region %d landing pad", i
);
3359 dw2_asm_output_data_uleb128 (cs
->action
, "action");
3362 call_site_base
+= n
;
3365 /* Tell assembler to switch to the section for the exception handling
3369 default_exception_section (void)
3371 if (targetm
.have_named_sections
)
3375 if (EH_TABLES_CAN_BE_READ_ONLY
)
3377 int tt_format
= ASM_PREFERRED_EH_DATA_FORMAT (/*code=*/0, /*global=*/1);
3380 || ((tt_format
& 0x70) != DW_EH_PE_absptr
3381 && (tt_format
& 0x70) != DW_EH_PE_aligned
))
3382 ? 0 : SECTION_WRITE
;
3385 flags
= SECTION_WRITE
;
3386 named_section_flags (".gcc_except_table", flags
);
3391 readonly_data_section ();
3395 /* Output a reference from an exception table to the type_info object TYPE.
3396 TT_FORMAT and TT_FORMAT_SIZE descibe the DWARF encoding method used for
3400 output_ttype (tree type
, int tt_format
, int tt_format_size
)
3404 if (type
== NULL_TREE
)
3408 struct cgraph_varpool_node
*node
;
3410 type
= lookup_type_for_runtime (type
);
3411 value
= expand_expr (type
, NULL_RTX
, VOIDmode
, EXPAND_INITIALIZER
);
3413 /* Let cgraph know that the rtti decl is used. Not all of the
3414 paths below go through assemble_integer, which would take
3415 care of this for us. */
3417 if (TREE_CODE (type
) == ADDR_EXPR
)
3419 type
= TREE_OPERAND (type
, 0);
3420 if (TREE_CODE (type
) == VAR_DECL
)
3422 node
= cgraph_varpool_node (type
);
3424 cgraph_varpool_mark_needed_node (node
);
3427 else if (TREE_CODE (type
) != INTEGER_CST
)
3431 /* Allow the target to override the type table entry format. */
3432 if (targetm
.asm_out
.ttype (value
))
3435 if (tt_format
== DW_EH_PE_absptr
|| tt_format
== DW_EH_PE_aligned
)
3436 assemble_integer (value
, tt_format_size
,
3437 tt_format_size
* BITS_PER_UNIT
, 1);
3439 dw2_asm_output_encoded_addr_rtx (tt_format
, value
, NULL
);
3443 output_function_exception_table (void)
3445 int tt_format
, cs_format
, lp_format
, i
, n
;
3446 #ifdef HAVE_AS_LEB128
3447 char ttype_label
[32];
3448 char cs_after_size_label
[32];
3449 char cs_end_label
[32];
3454 int tt_format_size
= 0;
3456 /* Not all functions need anything. */
3457 if (! cfun
->uses_eh_lsda
)
3460 #ifdef TARGET_UNWIND_INFO
3461 /* TODO: Move this into target file. */
3462 assemble_external_libcall (eh_personality_libfunc
);
3463 fputs ("\t.personality\t", asm_out_file
);
3464 output_addr_const (asm_out_file
, eh_personality_libfunc
);
3465 fputs ("\n\t.handlerdata\n", asm_out_file
);
3466 /* Note that varasm still thinks we're in the function's code section.
3467 The ".endp" directive that will immediately follow will take us back. */
3469 targetm
.asm_out
.exception_section ();
3472 have_tt_data
= (VEC_length (tree
, cfun
->eh
->ttype_data
) > 0
3473 || VARRAY_ACTIVE_SIZE (cfun
->eh
->ehspec_data
) > 0);
3475 /* Indicate the format of the @TType entries. */
3477 tt_format
= DW_EH_PE_omit
;
3480 tt_format
= ASM_PREFERRED_EH_DATA_FORMAT (/*code=*/0, /*global=*/1);
3481 #ifdef HAVE_AS_LEB128
3482 ASM_GENERATE_INTERNAL_LABEL (ttype_label
, "LLSDATT",
3483 current_function_funcdef_no
);
3485 tt_format_size
= size_of_encoded_value (tt_format
);
3487 assemble_align (tt_format_size
* BITS_PER_UNIT
);
3490 targetm
.asm_out
.internal_label (asm_out_file
, "LLSDA",
3491 current_function_funcdef_no
);
3493 /* The LSDA header. */
3495 /* Indicate the format of the landing pad start pointer. An omitted
3496 field implies @LPStart == @Start. */
3497 /* Currently we always put @LPStart == @Start. This field would
3498 be most useful in moving the landing pads completely out of
3499 line to another section, but it could also be used to minimize
3500 the size of uleb128 landing pad offsets. */
3501 lp_format
= DW_EH_PE_omit
;
3502 dw2_asm_output_data (1, lp_format
, "@LPStart format (%s)",
3503 eh_data_format_name (lp_format
));
3505 /* @LPStart pointer would go here. */
3507 dw2_asm_output_data (1, tt_format
, "@TType format (%s)",
3508 eh_data_format_name (tt_format
));
3510 #ifndef HAVE_AS_LEB128
3511 if (USING_SJLJ_EXCEPTIONS
)
3512 call_site_len
= sjlj_size_of_call_site_table ();
3514 call_site_len
= dw2_size_of_call_site_table ();
3517 /* A pc-relative 4-byte displacement to the @TType data. */
3520 #ifdef HAVE_AS_LEB128
3521 char ttype_after_disp_label
[32];
3522 ASM_GENERATE_INTERNAL_LABEL (ttype_after_disp_label
, "LLSDATTD",
3523 current_function_funcdef_no
);
3524 dw2_asm_output_delta_uleb128 (ttype_label
, ttype_after_disp_label
,
3525 "@TType base offset");
3526 ASM_OUTPUT_LABEL (asm_out_file
, ttype_after_disp_label
);
3528 /* Ug. Alignment queers things. */
3529 unsigned int before_disp
, after_disp
, last_disp
, disp
;
3531 before_disp
= 1 + 1;
3532 after_disp
= (1 + size_of_uleb128 (call_site_len
)
3534 + VARRAY_ACTIVE_SIZE (cfun
->eh
->action_record_data
)
3535 + (VEC_length (tree
, cfun
->eh
->ttype_data
)
3541 unsigned int disp_size
, pad
;
3544 disp_size
= size_of_uleb128 (disp
);
3545 pad
= before_disp
+ disp_size
+ after_disp
;
3546 if (pad
% tt_format_size
)
3547 pad
= tt_format_size
- (pad
% tt_format_size
);
3550 disp
= after_disp
+ pad
;
3552 while (disp
!= last_disp
);
3554 dw2_asm_output_data_uleb128 (disp
, "@TType base offset");
3558 /* Indicate the format of the call-site offsets. */
3559 #ifdef HAVE_AS_LEB128
3560 cs_format
= DW_EH_PE_uleb128
;
3562 cs_format
= DW_EH_PE_udata4
;
3564 dw2_asm_output_data (1, cs_format
, "call-site format (%s)",
3565 eh_data_format_name (cs_format
));
3567 #ifdef HAVE_AS_LEB128
3568 ASM_GENERATE_INTERNAL_LABEL (cs_after_size_label
, "LLSDACSB",
3569 current_function_funcdef_no
);
3570 ASM_GENERATE_INTERNAL_LABEL (cs_end_label
, "LLSDACSE",
3571 current_function_funcdef_no
);
3572 dw2_asm_output_delta_uleb128 (cs_end_label
, cs_after_size_label
,
3573 "Call-site table length");
3574 ASM_OUTPUT_LABEL (asm_out_file
, cs_after_size_label
);
3575 if (USING_SJLJ_EXCEPTIONS
)
3576 sjlj_output_call_site_table ();
3578 dw2_output_call_site_table ();
3579 ASM_OUTPUT_LABEL (asm_out_file
, cs_end_label
);
3581 dw2_asm_output_data_uleb128 (call_site_len
,"Call-site table length");
3582 if (USING_SJLJ_EXCEPTIONS
)
3583 sjlj_output_call_site_table ();
3585 dw2_output_call_site_table ();
3588 /* ??? Decode and interpret the data for flag_debug_asm. */
3589 n
= VARRAY_ACTIVE_SIZE (cfun
->eh
->action_record_data
);
3590 for (i
= 0; i
< n
; ++i
)
3591 dw2_asm_output_data (1, VARRAY_UCHAR (cfun
->eh
->action_record_data
, i
),
3592 (i
? NULL
: "Action record table"));
3595 assemble_align (tt_format_size
* BITS_PER_UNIT
);
3597 i
= VEC_length (tree
, cfun
->eh
->ttype_data
);
3600 tree type
= VEC_index (tree
, cfun
->eh
->ttype_data
, i
);
3601 output_ttype (type
, tt_format
, tt_format_size
);
3604 #ifdef HAVE_AS_LEB128
3606 ASM_OUTPUT_LABEL (asm_out_file
, ttype_label
);
3609 /* ??? Decode and interpret the data for flag_debug_asm. */
3610 n
= VARRAY_ACTIVE_SIZE (cfun
->eh
->ehspec_data
);
3611 for (i
= 0; i
< n
; ++i
)
3613 if (targetm
.arm_eabi_unwinder
)
3615 tree type
= VARRAY_TREE (cfun
->eh
->ehspec_data
, i
);
3616 output_ttype (type
, tt_format
, tt_format_size
);
3619 dw2_asm_output_data (1, VARRAY_UCHAR (cfun
->eh
->ehspec_data
, i
),
3620 (i
? NULL
: "Exception specification table"));
3623 current_function_section (current_function_decl
);
3627 set_eh_throw_stmt_table (struct function
*fun
, struct htab
*table
)
3629 fun
->eh
->throw_stmt_table
= table
;
3633 get_eh_throw_stmt_table (struct function
*fun
)
3635 return fun
->eh
->throw_stmt_table
;
3638 /* Dump EH information to OUT. */
3640 dump_eh_tree (FILE *out
, struct function
*fun
)
3642 struct eh_region
*i
;
3644 static const char * const type_name
[] = {"unknown", "cleanup", "try", "catch",
3645 "allowed_exceptions", "must_not_throw",
3648 i
= fun
->eh
->region_tree
;
3652 fprintf (out
, "Eh tree:\n");
3655 fprintf (out
, " %*s %i %s", depth
* 2, "",
3656 i
->region_number
, type_name
[(int)i
->type
]);
3659 fprintf (out
, " tree_label:");
3660 print_generic_expr (out
, i
->tree_label
, 0);
3662 fprintf (out
, "\n");
3663 /* If there are sub-regions, process them. */
3665 i
= i
->inner
, depth
++;
3666 /* If there are peers, process them. */
3667 else if (i
->next_peer
)
3669 /* Otherwise, step back up the tree to the next peer. */
3677 } while (i
->next_peer
== NULL
);
3683 /* Verify some basic invariants on EH datastructures. Could be extended to
3686 verify_eh_tree (struct function
*fun
)
3688 struct eh_region
*i
, *outer
= NULL
;
3695 i
= fun
->eh
->region_tree
;
3698 for (j
= fun
->eh
->last_region_number
; j
> 0; --j
)
3699 if (fun
->eh
->region_array
[j
])
3702 if (fun
->eh
->region_array
[j
]->region_number
!= j
)
3704 error ("region_array is corrupted for region %i", i
->region_number
);
3711 if (fun
->eh
->region_array
[i
->region_number
] != i
)
3713 error ("region_array is corrupted for region %i", i
->region_number
);
3716 if (i
->outer
!= outer
)
3718 error ("outer block of region %i is wrong", i
->region_number
);
3721 if (i
->may_contain_throw
&& outer
&& !outer
->may_contain_throw
)
3723 error ("region %i may contain throw and is contained in region that may not",
3729 error ("negative nesting depth of region %i", i
->region_number
);
3733 /* If there are sub-regions, process them. */
3735 outer
= i
, i
= i
->inner
, depth
++;
3736 /* If there are peers, process them. */
3737 else if (i
->next_peer
)
3739 /* Otherwise, step back up the tree to the next peer. */
3749 error ("Tree list ends on depth %i", depth
+ 1);
3752 if (count
!= nvisited
)
3754 error ("array does not match the region tree");
3759 dump_eh_tree (stderr
, fun
);
3760 internal_error ("verify_eh_tree failed.");
3765 } while (i
->next_peer
== NULL
);
3772 /* Initialize unwind_resume_libfunc. */
3775 default_init_unwind_resume_libfunc (void)
3777 /* The default c++ routines aren't actually c++ specific, so use those. */
3778 unwind_resume_libfunc
=
3779 init_one_libfunc ( USING_SJLJ_EXCEPTIONS
? "_Unwind_SjLj_Resume"
3780 : "_Unwind_Resume");
3783 #include "gt-except.h"