1 /* Implements exception handling.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001 Free Software Foundation, Inc.
4 Contributed by Mike Stump <mrs@cygnus.com>.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 2, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to the Free
20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
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. ] */
58 #include "insn-config.h"
60 #include "integrate.h"
61 #include "hard-reg-set.h"
62 #include "basic-block.h"
64 #include "dwarf2asm.h"
65 #include "dwarf2out.h"
74 /* Provide defaults for stuff that may not be defined when using
76 #ifndef EH_RETURN_STACKADJ_RTX
77 #define EH_RETURN_STACKADJ_RTX 0
79 #ifndef EH_RETURN_HANDLER_RTX
80 #define EH_RETURN_HANDLER_RTX 0
82 #ifndef EH_RETURN_DATA_REGNO
83 #define EH_RETURN_DATA_REGNO(N) INVALID_REGNUM
87 /* Nonzero means enable synchronous exceptions for non-call instructions. */
88 int flag_non_call_exceptions
;
90 /* Protect cleanup actions with must-not-throw regions, with a call
91 to the given failure handler. */
92 tree (*lang_protect_cleanup_actions
) PARAMS ((void));
94 /* Return true if type A catches type B. */
95 int (*lang_eh_type_covers
) PARAMS ((tree a
, tree b
));
97 /* Map a type to a runtime object to match type. */
98 tree (*lang_eh_runtime_type
) PARAMS ((tree
));
100 /* A list of labels used for exception handlers. */
101 rtx exception_handler_labels
;
103 static int call_site_base
;
104 static unsigned int sjlj_funcdef_number
;
105 static htab_t type_to_runtime_map
;
107 /* Describe the SjLj_Function_Context structure. */
108 static tree sjlj_fc_type_node
;
109 static int sjlj_fc_call_site_ofs
;
110 static int sjlj_fc_data_ofs
;
111 static int sjlj_fc_personality_ofs
;
112 static int sjlj_fc_lsda_ofs
;
113 static int sjlj_fc_jbuf_ofs
;
115 /* Describes one exception region. */
118 /* The immediately surrounding region. */
119 struct eh_region
*outer
;
121 /* The list of immediately contained regions. */
122 struct eh_region
*inner
;
123 struct eh_region
*next_peer
;
125 /* An identifier for this region. */
128 /* Each region does exactly one thing. */
135 ERT_ALLOWED_EXCEPTIONS
,
141 /* Holds the action to perform based on the preceding type. */
143 /* A list of catch blocks, a surrounding try block,
144 and the label for continuing after a catch. */
146 struct eh_region
*catch;
147 struct eh_region
*last_catch
;
148 struct eh_region
*prev_try
;
152 /* The list through the catch handlers, the list of type objects
153 matched, and the list of associated filters. */
155 struct eh_region
*next_catch
;
156 struct eh_region
*prev_catch
;
161 /* A tree_list of allowed types. */
167 /* The type given by a call to "throw foo();", or discovered
173 /* Retain the cleanup expression even after expansion so that
174 we can match up fixup regions. */
179 /* The real region (by expression and by pointer) that fixup code
183 struct eh_region
*real_region
;
187 /* Entry point for this region's handler before landing pads are built. */
190 /* Entry point for this region's handler from the runtime eh library. */
193 /* Entry point for this region's handler from an inner region. */
194 rtx post_landing_pad
;
196 /* The RESX insn for handing off control to the next outermost handler,
201 /* Used to save exception status for each function. */
204 /* The tree of all regions for this function. */
205 struct eh_region
*region_tree
;
207 /* The same information as an indexable array. */
208 struct eh_region
**region_array
;
210 /* The most recently open region. */
211 struct eh_region
*cur_region
;
213 /* This is the region for which we are processing catch blocks. */
214 struct eh_region
*try_region
;
216 /* A stack (TREE_LIST) of lists of handlers. The TREE_VALUE of each
217 node is itself a TREE_CHAINed list of handlers for regions that
218 are not yet closed. The TREE_VALUE of each entry contains the
219 handler for the corresponding entry on the ehstack. */
225 int built_landing_pads
;
226 int last_region_number
;
228 varray_type ttype_data
;
229 varray_type ehspec_data
;
230 varray_type action_record_data
;
232 struct call_site_record
237 int call_site_data_used
;
238 int call_site_data_size
;
249 static void mark_eh_region
PARAMS ((struct eh_region
*));
251 static int t2r_eq
PARAMS ((const PTR
,
253 static hashval_t t2r_hash
PARAMS ((const PTR
));
254 static int t2r_mark_1
PARAMS ((PTR
*, PTR
));
255 static void t2r_mark
PARAMS ((PTR
));
256 static void add_type_for_runtime
PARAMS ((tree
));
257 static tree lookup_type_for_runtime
PARAMS ((tree
));
259 static struct eh_region
*expand_eh_region_end
PARAMS ((void));
261 static rtx get_exception_filter
PARAMS ((struct function
*));
263 static void collect_eh_region_array
PARAMS ((void));
264 static void resolve_fixup_regions
PARAMS ((void));
265 static void remove_fixup_regions
PARAMS ((void));
266 static void convert_from_eh_region_ranges_1
PARAMS ((rtx
*, int *, int));
268 static struct eh_region
*duplicate_eh_region_1
PARAMS ((struct eh_region
*,
269 struct inline_remap
*));
270 static void duplicate_eh_region_2
PARAMS ((struct eh_region
*,
271 struct eh_region
**));
272 static int ttypes_filter_eq
PARAMS ((const PTR
,
274 static hashval_t ttypes_filter_hash
PARAMS ((const PTR
));
275 static int ehspec_filter_eq
PARAMS ((const PTR
,
277 static hashval_t ehspec_filter_hash
PARAMS ((const PTR
));
278 static int add_ttypes_entry
PARAMS ((htab_t
, tree
));
279 static int add_ehspec_entry
PARAMS ((htab_t
, htab_t
,
281 static void assign_filter_values
PARAMS ((void));
282 static void build_post_landing_pads
PARAMS ((void));
283 static void connect_post_landing_pads
PARAMS ((void));
284 static void dw2_build_landing_pads
PARAMS ((void));
287 static bool sjlj_find_directly_reachable_regions
288 PARAMS ((struct sjlj_lp_info
*));
289 static void sjlj_assign_call_site_values
290 PARAMS ((rtx
, struct sjlj_lp_info
*));
291 static void sjlj_mark_call_sites
292 PARAMS ((struct sjlj_lp_info
*));
293 static void sjlj_emit_function_enter
PARAMS ((rtx
));
294 static void sjlj_emit_function_exit
PARAMS ((void));
295 static void sjlj_emit_dispatch_table
296 PARAMS ((rtx
, struct sjlj_lp_info
*));
297 static void sjlj_build_landing_pads
PARAMS ((void));
299 static void remove_exception_handler_label
PARAMS ((rtx
));
300 static void remove_eh_handler
PARAMS ((struct eh_region
*));
302 struct reachable_info
;
304 /* The return value of reachable_next_level. */
307 /* The given exception is not processed by the given region. */
309 /* The given exception may need processing by the given region. */
311 /* The given exception is completely processed by the given region. */
313 /* The given exception is completely processed by the runtime. */
317 static int check_handled
PARAMS ((tree
, tree
));
318 static void add_reachable_handler
319 PARAMS ((struct reachable_info
*, struct eh_region
*,
320 struct eh_region
*));
321 static enum reachable_code reachable_next_level
322 PARAMS ((struct eh_region
*, tree
, struct reachable_info
*));
324 static int action_record_eq
PARAMS ((const PTR
,
326 static hashval_t action_record_hash
PARAMS ((const PTR
));
327 static int add_action_record
PARAMS ((htab_t
, int, int));
328 static int collect_one_action_chain
PARAMS ((htab_t
,
329 struct eh_region
*));
330 static int add_call_site
PARAMS ((rtx
, int));
332 static void push_uleb128
PARAMS ((varray_type
*,
334 static void push_sleb128
PARAMS ((varray_type
*, int));
335 #ifndef HAVE_AS_LEB128
336 static int dw2_size_of_call_site_table
PARAMS ((void));
337 static int sjlj_size_of_call_site_table
PARAMS ((void));
339 static void dw2_output_call_site_table
PARAMS ((void));
340 static void sjlj_output_call_site_table
PARAMS ((void));
343 /* Routine to see if exception handling is turned on.
344 DO_WARN is non-zero if we want to inform the user that exception
345 handling is turned off.
347 This is used to ensure that -fexceptions has been specified if the
348 compiler tries to use any exception-specific functions. */
354 if (! flag_exceptions
)
356 static int warned
= 0;
357 if (! warned
&& do_warn
)
359 error ("exception handling disabled, use -fexceptions to enable");
371 ggc_add_rtx_root (&exception_handler_labels
, 1);
373 if (! flag_exceptions
)
376 type_to_runtime_map
= htab_create (31, t2r_hash
, t2r_eq
, NULL
);
377 ggc_add_root (&type_to_runtime_map
, 1, sizeof (htab_t
), t2r_mark
);
379 /* Create the SjLj_Function_Context structure. This should match
380 the definition in unwind-sjlj.c. */
381 if (USING_SJLJ_EXCEPTIONS
)
383 tree f_jbuf
, f_per
, f_lsda
, f_prev
, f_cs
, f_data
, tmp
;
385 sjlj_fc_type_node
= make_lang_type (RECORD_TYPE
);
386 ggc_add_tree_root (&sjlj_fc_type_node
, 1);
388 f_prev
= build_decl (FIELD_DECL
, get_identifier ("__prev"),
389 build_pointer_type (sjlj_fc_type_node
));
390 DECL_FIELD_CONTEXT (f_prev
) = sjlj_fc_type_node
;
392 f_cs
= build_decl (FIELD_DECL
, get_identifier ("__call_site"),
394 DECL_FIELD_CONTEXT (f_cs
) = sjlj_fc_type_node
;
396 tmp
= build_index_type (build_int_2 (4 - 1, 0));
397 tmp
= build_array_type (type_for_mode (word_mode
, 1), tmp
);
398 f_data
= build_decl (FIELD_DECL
, get_identifier ("__data"), tmp
);
399 DECL_FIELD_CONTEXT (f_data
) = sjlj_fc_type_node
;
401 f_per
= build_decl (FIELD_DECL
, get_identifier ("__personality"),
403 DECL_FIELD_CONTEXT (f_per
) = sjlj_fc_type_node
;
405 f_lsda
= build_decl (FIELD_DECL
, get_identifier ("__lsda"),
407 DECL_FIELD_CONTEXT (f_lsda
) = sjlj_fc_type_node
;
409 #ifdef DONT_USE_BUILTIN_SETJMP
411 tmp
= build_int_2 (JMP_BUF_SIZE
- 1, 0);
413 /* Should be large enough for most systems, if it is not,
414 JMP_BUF_SIZE should be defined with the proper value. It will
415 also tend to be larger than necessary for most systems, a more
416 optimal port will define JMP_BUF_SIZE. */
417 tmp
= build_int_2 (FIRST_PSEUDO_REGISTER
+ 2 - 1, 0);
420 /* This is 2 for builtin_setjmp, plus whatever the target requires
421 via STACK_SAVEAREA_MODE (SAVE_NONLOCAL). */
422 tmp
= build_int_2 ((GET_MODE_SIZE (STACK_SAVEAREA_MODE (SAVE_NONLOCAL
))
423 / GET_MODE_SIZE (Pmode
)) + 2 - 1, 0);
425 tmp
= build_index_type (tmp
);
426 tmp
= build_array_type (ptr_type_node
, tmp
);
427 f_jbuf
= build_decl (FIELD_DECL
, get_identifier ("__jbuf"), tmp
);
428 #ifdef DONT_USE_BUILTIN_SETJMP
429 /* We don't know what the alignment requirements of the
430 runtime's jmp_buf has. Overestimate. */
431 DECL_ALIGN (f_jbuf
) = BIGGEST_ALIGNMENT
;
432 DECL_USER_ALIGN (f_jbuf
) = 1;
434 DECL_FIELD_CONTEXT (f_jbuf
) = sjlj_fc_type_node
;
436 TYPE_FIELDS (sjlj_fc_type_node
) = f_prev
;
437 TREE_CHAIN (f_prev
) = f_cs
;
438 TREE_CHAIN (f_cs
) = f_data
;
439 TREE_CHAIN (f_data
) = f_per
;
440 TREE_CHAIN (f_per
) = f_lsda
;
441 TREE_CHAIN (f_lsda
) = f_jbuf
;
443 layout_type (sjlj_fc_type_node
);
445 /* Cache the interesting field offsets so that we have
446 easy access from rtl. */
447 sjlj_fc_call_site_ofs
448 = (tree_low_cst (DECL_FIELD_OFFSET (f_cs
), 1)
449 + tree_low_cst (DECL_FIELD_BIT_OFFSET (f_cs
), 1) / BITS_PER_UNIT
);
451 = (tree_low_cst (DECL_FIELD_OFFSET (f_data
), 1)
452 + tree_low_cst (DECL_FIELD_BIT_OFFSET (f_data
), 1) / BITS_PER_UNIT
);
453 sjlj_fc_personality_ofs
454 = (tree_low_cst (DECL_FIELD_OFFSET (f_per
), 1)
455 + tree_low_cst (DECL_FIELD_BIT_OFFSET (f_per
), 1) / BITS_PER_UNIT
);
457 = (tree_low_cst (DECL_FIELD_OFFSET (f_lsda
), 1)
458 + tree_low_cst (DECL_FIELD_BIT_OFFSET (f_lsda
), 1) / BITS_PER_UNIT
);
460 = (tree_low_cst (DECL_FIELD_OFFSET (f_jbuf
), 1)
461 + tree_low_cst (DECL_FIELD_BIT_OFFSET (f_jbuf
), 1) / BITS_PER_UNIT
);
466 init_eh_for_function ()
468 cfun
->eh
= (struct eh_status
*) xcalloc (1, sizeof (struct eh_status
));
471 /* Mark EH for GC. */
474 mark_eh_region (region
)
475 struct eh_region
*region
;
480 switch (region
->type
)
483 /* This can happen if a nested function is inside the body of a region
484 and we do a GC as part of processing it. */
487 ggc_mark_tree (region
->u
.cleanup
.exp
);
490 ggc_mark_rtx (region
->u
.try.continue_label
);
493 ggc_mark_tree (region
->u
.catch.type_list
);
494 ggc_mark_tree (region
->u
.catch.filter_list
);
496 case ERT_ALLOWED_EXCEPTIONS
:
497 ggc_mark_tree (region
->u
.allowed
.type_list
);
499 case ERT_MUST_NOT_THROW
:
502 ggc_mark_tree (region
->u
.throw.type
);
505 ggc_mark_tree (region
->u
.fixup
.cleanup_exp
);
511 ggc_mark_rtx (region
->label
);
512 ggc_mark_rtx (region
->resume
);
513 ggc_mark_rtx (region
->landing_pad
);
514 ggc_mark_rtx (region
->post_landing_pad
);
519 struct eh_status
*eh
;
526 /* If we've called collect_eh_region_array, use it. Otherwise walk
527 the tree non-recursively. */
528 if (eh
->region_array
)
530 for (i
= eh
->last_region_number
; i
> 0; --i
)
532 struct eh_region
*r
= eh
->region_array
[i
];
533 if (r
&& r
->region_number
== i
)
537 else if (eh
->region_tree
)
539 struct eh_region
*r
= eh
->region_tree
;
545 else if (r
->next_peer
)
553 } while (r
->next_peer
== NULL
);
560 ggc_mark_tree (eh
->protect_list
);
561 ggc_mark_rtx (eh
->filter
);
562 ggc_mark_rtx (eh
->exc_ptr
);
563 ggc_mark_tree_varray (eh
->ttype_data
);
565 if (eh
->call_site_data
)
567 for (i
= eh
->call_site_data_used
- 1; i
>= 0; --i
)
568 ggc_mark_rtx (eh
->call_site_data
[i
].landing_pad
);
571 ggc_mark_rtx (eh
->ehr_stackadj
);
572 ggc_mark_rtx (eh
->ehr_handler
);
573 ggc_mark_rtx (eh
->ehr_label
);
575 ggc_mark_rtx (eh
->sjlj_fc
);
576 ggc_mark_rtx (eh
->sjlj_exit_after
);
583 struct eh_status
*eh
= f
->eh
;
585 if (eh
->region_array
)
588 for (i
= eh
->last_region_number
; i
> 0; --i
)
590 struct eh_region
*r
= eh
->region_array
[i
];
591 /* Mind we don't free a region struct more than once. */
592 if (r
&& r
->region_number
== i
)
595 free (eh
->region_array
);
597 else if (eh
->region_tree
)
599 struct eh_region
*next
, *r
= eh
->region_tree
;
604 else if (r
->next_peer
)
618 } while (r
->next_peer
== NULL
);
627 VARRAY_FREE (eh
->ttype_data
);
628 VARRAY_FREE (eh
->ehspec_data
);
629 VARRAY_FREE (eh
->action_record_data
);
630 if (eh
->call_site_data
)
631 free (eh
->call_site_data
);
638 /* Start an exception handling region. All instructions emitted
639 after this point are considered to be part of the region until
640 expand_eh_region_end is invoked. */
643 expand_eh_region_start ()
645 struct eh_region
*new_region
;
646 struct eh_region
*cur_region
;
652 /* Insert a new blank region as a leaf in the tree. */
653 new_region
= (struct eh_region
*) xcalloc (1, sizeof (*new_region
));
654 cur_region
= cfun
->eh
->cur_region
;
655 new_region
->outer
= cur_region
;
658 new_region
->next_peer
= cur_region
->inner
;
659 cur_region
->inner
= new_region
;
663 new_region
->next_peer
= cfun
->eh
->region_tree
;
664 cfun
->eh
->region_tree
= new_region
;
666 cfun
->eh
->cur_region
= new_region
;
668 /* Create a note marking the start of this region. */
669 new_region
->region_number
= ++cfun
->eh
->last_region_number
;
670 note
= emit_note (NULL
, NOTE_INSN_EH_REGION_BEG
);
671 NOTE_EH_HANDLER (note
) = new_region
->region_number
;
674 /* Common code to end a region. Returns the region just ended. */
676 static struct eh_region
*
677 expand_eh_region_end ()
679 struct eh_region
*cur_region
= cfun
->eh
->cur_region
;
682 /* Create a note marking the end of this region. */
683 note
= emit_note (NULL
, NOTE_INSN_EH_REGION_END
);
684 NOTE_EH_HANDLER (note
) = cur_region
->region_number
;
687 cfun
->eh
->cur_region
= cur_region
->outer
;
692 /* End an exception handling region for a cleanup. HANDLER is an
693 expression to expand for the cleanup. */
696 expand_eh_region_end_cleanup (handler
)
699 struct eh_region
*region
;
700 tree protect_cleanup_actions
;
707 region
= expand_eh_region_end ();
708 region
->type
= ERT_CLEANUP
;
709 region
->label
= gen_label_rtx ();
710 region
->u
.cleanup
.exp
= handler
;
712 around_label
= gen_label_rtx ();
713 emit_jump (around_label
);
715 emit_label (region
->label
);
717 /* Give the language a chance to specify an action to be taken if an
718 exception is thrown that would propagate out of the HANDLER. */
719 protect_cleanup_actions
720 = (lang_protect_cleanup_actions
721 ? (*lang_protect_cleanup_actions
) ()
724 if (protect_cleanup_actions
)
725 expand_eh_region_start ();
727 /* In case this cleanup involves an inline destructor with a try block in
728 it, we need to save the EH return data registers around it. */
729 data_save
[0] = gen_reg_rtx (Pmode
);
730 emit_move_insn (data_save
[0], get_exception_pointer (cfun
));
731 data_save
[1] = gen_reg_rtx (word_mode
);
732 emit_move_insn (data_save
[1], get_exception_filter (cfun
));
734 expand_expr (handler
, const0_rtx
, VOIDmode
, 0);
736 emit_move_insn (cfun
->eh
->exc_ptr
, data_save
[0]);
737 emit_move_insn (cfun
->eh
->filter
, data_save
[1]);
739 if (protect_cleanup_actions
)
740 expand_eh_region_end_must_not_throw (protect_cleanup_actions
);
742 /* We need any stack adjustment complete before the around_label. */
743 do_pending_stack_adjust ();
745 /* We delay the generation of the _Unwind_Resume until we generate
746 landing pads. We emit a marker here so as to get good control
747 flow data in the meantime. */
749 = emit_jump_insn (gen_rtx_RESX (VOIDmode
, region
->region_number
));
752 emit_label (around_label
);
755 /* End an exception handling region for a try block, and prepares
756 for subsequent calls to expand_start_catch. */
759 expand_start_all_catch ()
761 struct eh_region
*region
;
766 region
= expand_eh_region_end ();
767 region
->type
= ERT_TRY
;
768 region
->u
.try.prev_try
= cfun
->eh
->try_region
;
769 region
->u
.try.continue_label
= gen_label_rtx ();
771 cfun
->eh
->try_region
= region
;
773 emit_jump (region
->u
.try.continue_label
);
776 /* Begin a catch clause. TYPE is the type caught, a list of such types, or
777 null if this is a catch-all clause. Providing a type list enables to
778 associate the catch region with potentially several exception types, which
779 is useful e.g. for Ada. */
782 expand_start_catch (type_or_list
)
785 struct eh_region
*t
, *c
, *l
;
791 type_list
= type_or_list
;
795 /* Ensure to always end up with a type list to normalize further
796 processing, then register each type against the runtime types
800 if (TREE_CODE (type_or_list
) != TREE_LIST
)
801 type_list
= tree_cons (NULL_TREE
, type_or_list
, NULL_TREE
);
803 type_node
= type_list
;
804 for (; type_node
; type_node
= TREE_CHAIN (type_node
))
805 add_type_for_runtime (TREE_VALUE (type_node
));
808 expand_eh_region_start ();
810 t
= cfun
->eh
->try_region
;
811 c
= cfun
->eh
->cur_region
;
813 c
->u
.catch.type_list
= type_list
;
814 c
->label
= gen_label_rtx ();
816 l
= t
->u
.try.last_catch
;
817 c
->u
.catch.prev_catch
= l
;
819 l
->u
.catch.next_catch
= c
;
822 t
->u
.try.last_catch
= c
;
824 emit_label (c
->label
);
827 /* End a catch clause. Control will resume after the try/catch block. */
832 struct eh_region
*try_region
, *catch_region
;
837 catch_region
= expand_eh_region_end ();
838 try_region
= cfun
->eh
->try_region
;
840 emit_jump (try_region
->u
.try.continue_label
);
843 /* End a sequence of catch handlers for a try block. */
846 expand_end_all_catch ()
848 struct eh_region
*try_region
;
853 try_region
= cfun
->eh
->try_region
;
854 cfun
->eh
->try_region
= try_region
->u
.try.prev_try
;
856 emit_label (try_region
->u
.try.continue_label
);
859 /* End an exception region for an exception type filter. ALLOWED is a
860 TREE_LIST of types to be matched by the runtime. FAILURE is an
861 expression to invoke if a mismatch occurs.
863 ??? We could use these semantics for calls to rethrow, too; if we can
864 see the surrounding catch clause, we know that the exception we're
865 rethrowing satisfies the "filter" of the catch type. */
868 expand_eh_region_end_allowed (allowed
, failure
)
869 tree allowed
, failure
;
871 struct eh_region
*region
;
877 region
= expand_eh_region_end ();
878 region
->type
= ERT_ALLOWED_EXCEPTIONS
;
879 region
->u
.allowed
.type_list
= allowed
;
880 region
->label
= gen_label_rtx ();
882 for (; allowed
; allowed
= TREE_CHAIN (allowed
))
883 add_type_for_runtime (TREE_VALUE (allowed
));
885 /* We must emit the call to FAILURE here, so that if this function
886 throws a different exception, that it will be processed by the
889 around_label
= gen_label_rtx ();
890 emit_jump (around_label
);
892 emit_label (region
->label
);
893 expand_expr (failure
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
894 /* We must adjust the stack before we reach the AROUND_LABEL because
895 the call to FAILURE does not occur on all paths to the
897 do_pending_stack_adjust ();
899 emit_label (around_label
);
902 /* End an exception region for a must-not-throw filter. FAILURE is an
903 expression invoke if an uncaught exception propagates this far.
905 This is conceptually identical to expand_eh_region_end_allowed with
906 an empty allowed list (if you passed "std::terminate" instead of
907 "__cxa_call_unexpected"), but they are represented differently in
911 expand_eh_region_end_must_not_throw (failure
)
914 struct eh_region
*region
;
920 region
= expand_eh_region_end ();
921 region
->type
= ERT_MUST_NOT_THROW
;
922 region
->label
= gen_label_rtx ();
924 /* We must emit the call to FAILURE here, so that if this function
925 throws a different exception, that it will be processed by the
928 around_label
= gen_label_rtx ();
929 emit_jump (around_label
);
931 emit_label (region
->label
);
932 expand_expr (failure
, const0_rtx
, VOIDmode
, EXPAND_NORMAL
);
934 emit_label (around_label
);
937 /* End an exception region for a throw. No handling goes on here,
938 but it's the easiest way for the front-end to indicate what type
942 expand_eh_region_end_throw (type
)
945 struct eh_region
*region
;
950 region
= expand_eh_region_end ();
951 region
->type
= ERT_THROW
;
952 region
->u
.throw.type
= type
;
955 /* End a fixup region. Within this region the cleanups for the immediately
956 enclosing region are _not_ run. This is used for goto cleanup to avoid
957 destroying an object twice.
959 This would be an extraordinarily simple prospect, were it not for the
960 fact that we don't actually know what the immediately enclosing region
961 is. This surprising fact is because expand_cleanups is currently
962 generating a sequence that it will insert somewhere else. We collect
963 the proper notion of "enclosing" in convert_from_eh_region_ranges. */
966 expand_eh_region_end_fixup (handler
)
969 struct eh_region
*fixup
;
974 fixup
= expand_eh_region_end ();
975 fixup
->type
= ERT_FIXUP
;
976 fixup
->u
.fixup
.cleanup_exp
= handler
;
979 /* Return an rtl expression for a pointer to the exception object
983 get_exception_pointer (fun
)
984 struct function
*fun
;
986 rtx exc_ptr
= fun
->eh
->exc_ptr
;
987 if (fun
== cfun
&& ! exc_ptr
)
989 exc_ptr
= gen_reg_rtx (Pmode
);
990 fun
->eh
->exc_ptr
= exc_ptr
;
995 /* Return an rtl expression for the exception dispatch filter
999 get_exception_filter (fun
)
1000 struct function
*fun
;
1002 rtx filter
= fun
->eh
->filter
;
1003 if (fun
== cfun
&& ! filter
)
1005 filter
= gen_reg_rtx (word_mode
);
1006 fun
->eh
->filter
= filter
;
1011 /* Begin a region that will contain entries created with
1012 add_partial_entry. */
1015 begin_protect_partials ()
1017 /* Push room for a new list. */
1018 cfun
->eh
->protect_list
1019 = tree_cons (NULL_TREE
, NULL_TREE
, cfun
->eh
->protect_list
);
1022 /* Start a new exception region for a region of code that has a
1023 cleanup action and push the HANDLER for the region onto
1024 protect_list. All of the regions created with add_partial_entry
1025 will be ended when end_protect_partials is invoked. */
1028 add_partial_entry (handler
)
1031 expand_eh_region_start ();
1033 /* ??? This comment was old before the most recent rewrite. We
1034 really ought to fix the callers at some point. */
1035 /* For backwards compatibility, we allow callers to omit calls to
1036 begin_protect_partials for the outermost region. So, we must
1037 explicitly do so here. */
1038 if (!cfun
->eh
->protect_list
)
1039 begin_protect_partials ();
1041 /* Add this entry to the front of the list. */
1042 TREE_VALUE (cfun
->eh
->protect_list
)
1043 = tree_cons (NULL_TREE
, handler
, TREE_VALUE (cfun
->eh
->protect_list
));
1046 /* End all the pending exception regions on protect_list. */
1049 end_protect_partials ()
1053 /* ??? This comment was old before the most recent rewrite. We
1054 really ought to fix the callers at some point. */
1055 /* For backwards compatibility, we allow callers to omit the call to
1056 begin_protect_partials for the outermost region. So,
1057 PROTECT_LIST may be NULL. */
1058 if (!cfun
->eh
->protect_list
)
1061 /* Pop the topmost entry. */
1062 t
= TREE_VALUE (cfun
->eh
->protect_list
);
1063 cfun
->eh
->protect_list
= TREE_CHAIN (cfun
->eh
->protect_list
);
1065 /* End all the exception regions. */
1066 for (; t
; t
= TREE_CHAIN (t
))
1067 expand_eh_region_end_cleanup (TREE_VALUE (t
));
1071 /* This section is for the exception handling specific optimization pass. */
1073 /* Random access the exception region tree. It's just as simple to
1074 collect the regions this way as in expand_eh_region_start, but
1075 without having to realloc memory. */
1078 collect_eh_region_array ()
1080 struct eh_region
**array
, *i
;
1082 i
= cfun
->eh
->region_tree
;
1086 array
= xcalloc (cfun
->eh
->last_region_number
+ 1, sizeof (*array
));
1087 cfun
->eh
->region_array
= array
;
1091 array
[i
->region_number
] = i
;
1093 /* If there are sub-regions, process them. */
1096 /* If there are peers, process them. */
1097 else if (i
->next_peer
)
1099 /* Otherwise, step back up the tree to the next peer. */
1106 } while (i
->next_peer
== NULL
);
1113 resolve_fixup_regions ()
1115 int i
, j
, n
= cfun
->eh
->last_region_number
;
1117 for (i
= 1; i
<= n
; ++i
)
1119 struct eh_region
*fixup
= cfun
->eh
->region_array
[i
];
1120 struct eh_region
*cleanup
= 0;
1122 if (! fixup
|| fixup
->type
!= ERT_FIXUP
)
1125 for (j
= 1; j
<= n
; ++j
)
1127 cleanup
= cfun
->eh
->region_array
[j
];
1128 if (cleanup
->type
== ERT_CLEANUP
1129 && cleanup
->u
.cleanup
.exp
== fixup
->u
.fixup
.cleanup_exp
)
1135 fixup
->u
.fixup
.real_region
= cleanup
->outer
;
1139 /* Now that we've discovered what region actually encloses a fixup,
1140 we can shuffle pointers and remove them from the tree. */
1143 remove_fixup_regions ()
1147 struct eh_region
*fixup
;
1149 /* Walk the insn chain and adjust the REG_EH_REGION numbers
1150 for instructions referencing fixup regions. This is only
1151 strictly necessary for fixup regions with no parent, but
1152 doesn't hurt to do it for all regions. */
1153 for (insn
= get_insns(); insn
; insn
= NEXT_INSN (insn
))
1155 && (note
= find_reg_note (insn
, REG_EH_REGION
, NULL
))
1156 && INTVAL (XEXP (note
, 0)) > 0
1157 && (fixup
= cfun
->eh
->region_array
[INTVAL (XEXP (note
, 0))])
1158 && fixup
->type
== ERT_FIXUP
)
1160 if (fixup
->u
.fixup
.real_region
)
1161 XEXP (note
, 0) = GEN_INT (fixup
->u
.fixup
.real_region
->region_number
);
1163 remove_note (insn
, note
);
1166 /* Remove the fixup regions from the tree. */
1167 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1169 fixup
= cfun
->eh
->region_array
[i
];
1173 /* Allow GC to maybe free some memory. */
1174 if (fixup
->type
== ERT_CLEANUP
)
1175 fixup
->u
.cleanup
.exp
= NULL_TREE
;
1177 if (fixup
->type
!= ERT_FIXUP
)
1182 struct eh_region
*parent
, *p
, **pp
;
1184 parent
= fixup
->u
.fixup
.real_region
;
1186 /* Fix up the children's parent pointers; find the end of
1188 for (p
= fixup
->inner
; ; p
= p
->next_peer
)
1195 /* In the tree of cleanups, only outer-inner ordering matters.
1196 So link the children back in anywhere at the correct level. */
1198 pp
= &parent
->inner
;
1200 pp
= &cfun
->eh
->region_tree
;
1203 fixup
->inner
= NULL
;
1206 remove_eh_handler (fixup
);
1210 /* Turn NOTE_INSN_EH_REGION notes into REG_EH_REGION notes for each
1211 can_throw instruction in the region. */
1214 convert_from_eh_region_ranges_1 (pinsns
, orig_sp
, cur
)
1222 for (insn
= *pinsns
; insn
; insn
= next
)
1224 next
= NEXT_INSN (insn
);
1225 if (GET_CODE (insn
) == NOTE
)
1227 int kind
= NOTE_LINE_NUMBER (insn
);
1228 if (kind
== NOTE_INSN_EH_REGION_BEG
1229 || kind
== NOTE_INSN_EH_REGION_END
)
1231 if (kind
== NOTE_INSN_EH_REGION_BEG
)
1233 struct eh_region
*r
;
1236 cur
= NOTE_EH_HANDLER (insn
);
1238 r
= cfun
->eh
->region_array
[cur
];
1239 if (r
->type
== ERT_FIXUP
)
1241 r
= r
->u
.fixup
.real_region
;
1242 cur
= r
? r
->region_number
: 0;
1244 else if (r
->type
== ERT_CATCH
)
1247 cur
= r
? r
->region_number
: 0;
1253 /* Removing the first insn of a CALL_PLACEHOLDER sequence
1254 requires extra care to adjust sequence start. */
1255 if (insn
== *pinsns
)
1261 else if (INSN_P (insn
))
1264 && ! find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
)
1265 /* Calls can always potentially throw exceptions, unless
1266 they have a REG_EH_REGION note with a value of 0 or less.
1267 Which should be the only possible kind so far. */
1268 && (GET_CODE (insn
) == CALL_INSN
1269 /* If we wanted exceptions for non-call insns, then
1270 any may_trap_p instruction could throw. */
1271 || (flag_non_call_exceptions
1272 && GET_CODE (PATTERN (insn
)) != CLOBBER
1273 && GET_CODE (PATTERN (insn
)) != USE
1274 && may_trap_p (PATTERN (insn
)))))
1276 REG_NOTES (insn
) = alloc_EXPR_LIST (REG_EH_REGION
, GEN_INT (cur
),
1280 if (GET_CODE (insn
) == CALL_INSN
1281 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
1283 convert_from_eh_region_ranges_1 (&XEXP (PATTERN (insn
), 0),
1285 convert_from_eh_region_ranges_1 (&XEXP (PATTERN (insn
), 1),
1287 convert_from_eh_region_ranges_1 (&XEXP (PATTERN (insn
), 2),
1298 convert_from_eh_region_ranges ()
1303 collect_eh_region_array ();
1304 resolve_fixup_regions ();
1306 stack
= xmalloc (sizeof (int) * (cfun
->eh
->last_region_number
+ 1));
1307 insns
= get_insns ();
1308 convert_from_eh_region_ranges_1 (&insns
, stack
, 0);
1311 remove_fixup_regions ();
1315 find_exception_handler_labels ()
1317 rtx list
= NULL_RTX
;
1320 free_EXPR_LIST_list (&exception_handler_labels
);
1322 if (cfun
->eh
->region_tree
== NULL
)
1325 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1327 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
1332 if (cfun
->eh
->built_landing_pads
)
1333 lab
= region
->landing_pad
;
1335 lab
= region
->label
;
1338 list
= alloc_EXPR_LIST (0, lab
, list
);
1341 /* For sjlj exceptions, need the return label to remain live until
1342 after landing pad generation. */
1343 if (USING_SJLJ_EXCEPTIONS
&& ! cfun
->eh
->built_landing_pads
)
1344 list
= alloc_EXPR_LIST (0, return_label
, list
);
1346 exception_handler_labels
= list
;
1350 static struct eh_region
*
1351 duplicate_eh_region_1 (o
, map
)
1352 struct eh_region
*o
;
1353 struct inline_remap
*map
;
1356 = (struct eh_region
*) xcalloc (1, sizeof (struct eh_region
));
1358 n
->region_number
= o
->region_number
+ cfun
->eh
->last_region_number
;
1364 case ERT_MUST_NOT_THROW
:
1368 if (o
->u
.try.continue_label
)
1369 n
->u
.try.continue_label
1370 = get_label_from_map (map
,
1371 CODE_LABEL_NUMBER (o
->u
.try.continue_label
));
1375 n
->u
.catch.type_list
= o
->u
.catch.type_list
;
1378 case ERT_ALLOWED_EXCEPTIONS
:
1379 n
->u
.allowed
.type_list
= o
->u
.allowed
.type_list
;
1383 n
->u
.throw.type
= o
->u
.throw.type
;
1390 n
->label
= get_label_from_map (map
, CODE_LABEL_NUMBER (o
->label
));
1393 n
->resume
= map
->insn_map
[INSN_UID (o
->resume
)];
1394 if (n
->resume
== NULL
)
1402 duplicate_eh_region_2 (o
, n_array
)
1403 struct eh_region
*o
;
1404 struct eh_region
**n_array
;
1406 struct eh_region
*n
= n_array
[o
->region_number
];
1411 n
->u
.try.catch = n_array
[o
->u
.try.catch->region_number
];
1412 n
->u
.try.last_catch
= n_array
[o
->u
.try.last_catch
->region_number
];
1416 if (o
->u
.catch.next_catch
)
1417 n
->u
.catch.next_catch
= n_array
[o
->u
.catch.next_catch
->region_number
];
1418 if (o
->u
.catch.prev_catch
)
1419 n
->u
.catch.prev_catch
= n_array
[o
->u
.catch.prev_catch
->region_number
];
1427 n
->outer
= n_array
[o
->outer
->region_number
];
1429 n
->inner
= n_array
[o
->inner
->region_number
];
1431 n
->next_peer
= n_array
[o
->next_peer
->region_number
];
1435 duplicate_eh_regions (ifun
, map
)
1436 struct function
*ifun
;
1437 struct inline_remap
*map
;
1439 int ifun_last_region_number
= ifun
->eh
->last_region_number
;
1440 struct eh_region
**n_array
, *root
, *cur
;
1443 if (ifun_last_region_number
== 0)
1446 n_array
= xcalloc (ifun_last_region_number
+ 1, sizeof (*n_array
));
1448 for (i
= 1; i
<= ifun_last_region_number
; ++i
)
1450 cur
= ifun
->eh
->region_array
[i
];
1451 if (!cur
|| cur
->region_number
!= i
)
1453 n_array
[i
] = duplicate_eh_region_1 (cur
, map
);
1455 for (i
= 1; i
<= ifun_last_region_number
; ++i
)
1457 cur
= ifun
->eh
->region_array
[i
];
1458 if (!cur
|| cur
->region_number
!= i
)
1460 duplicate_eh_region_2 (cur
, n_array
);
1463 root
= n_array
[ifun
->eh
->region_tree
->region_number
];
1464 cur
= cfun
->eh
->cur_region
;
1467 struct eh_region
*p
= cur
->inner
;
1470 while (p
->next_peer
)
1472 p
->next_peer
= root
;
1477 for (i
= 1; i
<= ifun_last_region_number
; ++i
)
1478 if (n_array
[i
] && n_array
[i
]->outer
== NULL
)
1479 n_array
[i
]->outer
= cur
;
1483 struct eh_region
*p
= cfun
->eh
->region_tree
;
1486 while (p
->next_peer
)
1488 p
->next_peer
= root
;
1491 cfun
->eh
->region_tree
= root
;
1496 i
= cfun
->eh
->last_region_number
;
1497 cfun
->eh
->last_region_number
= i
+ ifun_last_region_number
;
1503 t2r_eq (pentry
, pdata
)
1507 tree entry
= (tree
) pentry
;
1508 tree data
= (tree
) pdata
;
1510 return TREE_PURPOSE (entry
) == data
;
1517 tree entry
= (tree
) pentry
;
1518 return TYPE_HASH (TREE_PURPOSE (entry
));
1522 t2r_mark_1 (slot
, data
)
1524 PTR data ATTRIBUTE_UNUSED
;
1526 tree contents
= (tree
) *slot
;
1527 ggc_mark_tree (contents
);
1535 htab_traverse (*(htab_t
*)addr
, t2r_mark_1
, NULL
);
1539 add_type_for_runtime (type
)
1544 slot
= (tree
*) htab_find_slot_with_hash (type_to_runtime_map
, type
,
1545 TYPE_HASH (type
), INSERT
);
1548 tree runtime
= (*lang_eh_runtime_type
) (type
);
1549 *slot
= tree_cons (type
, runtime
, NULL_TREE
);
1554 lookup_type_for_runtime (type
)
1559 slot
= (tree
*) htab_find_slot_with_hash (type_to_runtime_map
, type
,
1560 TYPE_HASH (type
), NO_INSERT
);
1562 /* We should have always inserted the data earlier. */
1563 return TREE_VALUE (*slot
);
1567 /* Represent an entry in @TTypes for either catch actions
1568 or exception filter actions. */
1569 struct ttypes_filter
1575 /* Compare ENTRY (a ttypes_filter entry in the hash table) with DATA
1576 (a tree) for a @TTypes type node we are thinking about adding. */
1579 ttypes_filter_eq (pentry
, pdata
)
1583 const struct ttypes_filter
*entry
= (const struct ttypes_filter
*) pentry
;
1584 tree data
= (tree
) pdata
;
1586 return entry
->t
== data
;
1590 ttypes_filter_hash (pentry
)
1593 const struct ttypes_filter
*entry
= (const struct ttypes_filter
*) pentry
;
1594 return TYPE_HASH (entry
->t
);
1597 /* Compare ENTRY with DATA (both struct ttypes_filter) for a @TTypes
1598 exception specification list we are thinking about adding. */
1599 /* ??? Currently we use the type lists in the order given. Someone
1600 should put these in some canonical order. */
1603 ehspec_filter_eq (pentry
, pdata
)
1607 const struct ttypes_filter
*entry
= (const struct ttypes_filter
*) pentry
;
1608 const struct ttypes_filter
*data
= (const struct ttypes_filter
*) pdata
;
1610 return type_list_equal (entry
->t
, data
->t
);
1613 /* Hash function for exception specification lists. */
1616 ehspec_filter_hash (pentry
)
1619 const struct ttypes_filter
*entry
= (const struct ttypes_filter
*) pentry
;
1623 for (list
= entry
->t
; list
; list
= TREE_CHAIN (list
))
1624 h
= (h
<< 5) + (h
>> 27) + TYPE_HASH (TREE_VALUE (list
));
1628 /* Add TYPE to cfun->eh->ttype_data, using TYPES_HASH to speed
1629 up the search. Return the filter value to be used. */
1632 add_ttypes_entry (ttypes_hash
, type
)
1636 struct ttypes_filter
**slot
, *n
;
1638 slot
= (struct ttypes_filter
**)
1639 htab_find_slot_with_hash (ttypes_hash
, type
, TYPE_HASH (type
), INSERT
);
1641 if ((n
= *slot
) == NULL
)
1643 /* Filter value is a 1 based table index. */
1645 n
= (struct ttypes_filter
*) xmalloc (sizeof (*n
));
1647 n
->filter
= VARRAY_ACTIVE_SIZE (cfun
->eh
->ttype_data
) + 1;
1650 VARRAY_PUSH_TREE (cfun
->eh
->ttype_data
, type
);
1656 /* Add LIST to cfun->eh->ehspec_data, using EHSPEC_HASH and TYPES_HASH
1657 to speed up the search. Return the filter value to be used. */
1660 add_ehspec_entry (ehspec_hash
, ttypes_hash
, list
)
1665 struct ttypes_filter
**slot
, *n
;
1666 struct ttypes_filter dummy
;
1669 slot
= (struct ttypes_filter
**)
1670 htab_find_slot (ehspec_hash
, &dummy
, INSERT
);
1672 if ((n
= *slot
) == NULL
)
1674 /* Filter value is a -1 based byte index into a uleb128 buffer. */
1676 n
= (struct ttypes_filter
*) xmalloc (sizeof (*n
));
1678 n
->filter
= -(VARRAY_ACTIVE_SIZE (cfun
->eh
->ehspec_data
) + 1);
1681 /* Look up each type in the list and encode its filter
1682 value as a uleb128. Terminate the list with 0. */
1683 for (; list
; list
= TREE_CHAIN (list
))
1684 push_uleb128 (&cfun
->eh
->ehspec_data
,
1685 add_ttypes_entry (ttypes_hash
, TREE_VALUE (list
)));
1686 VARRAY_PUSH_UCHAR (cfun
->eh
->ehspec_data
, 0);
1692 /* Generate the action filter values to be used for CATCH and
1693 ALLOWED_EXCEPTIONS regions. When using dwarf2 exception regions,
1694 we use lots of landing pads, and so every type or list can share
1695 the same filter value, which saves table space. */
1698 assign_filter_values ()
1701 htab_t ttypes
, ehspec
;
1703 VARRAY_TREE_INIT (cfun
->eh
->ttype_data
, 16, "ttype_data");
1704 VARRAY_UCHAR_INIT (cfun
->eh
->ehspec_data
, 64, "ehspec_data");
1706 ttypes
= htab_create (31, ttypes_filter_hash
, ttypes_filter_eq
, free
);
1707 ehspec
= htab_create (31, ehspec_filter_hash
, ehspec_filter_eq
, free
);
1709 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1711 struct eh_region
*r
= cfun
->eh
->region_array
[i
];
1713 /* Mind we don't process a region more than once. */
1714 if (!r
|| r
->region_number
!= i
)
1720 /* Whatever type_list is (NULL or true list), we build a list
1721 of filters for the region. */
1722 r
->u
.catch.filter_list
= NULL_TREE
;
1724 if (r
->u
.catch.type_list
!= NULL
)
1726 /* Get a filter value for each of the types caught and store
1727 them in the region's dedicated list. */
1728 tree tp_node
= r
->u
.catch.type_list
;
1730 for (;tp_node
; tp_node
= TREE_CHAIN (tp_node
))
1732 int flt
= add_ttypes_entry (ttypes
, TREE_VALUE (tp_node
));
1733 tree flt_node
= build_int_2 (flt
, 0);
1735 r
->u
.catch.filter_list
1736 = tree_cons (NULL_TREE
, flt_node
, r
->u
.catch.filter_list
);
1741 /* Get a filter value for the NULL list also since it will need
1742 an action record anyway. */
1743 int flt
= add_ttypes_entry (ttypes
, NULL
);
1744 tree flt_node
= build_int_2 (flt
, 0);
1746 r
->u
.catch.filter_list
1747 = tree_cons (NULL_TREE
, flt_node
, r
->u
.catch.filter_list
);
1752 case ERT_ALLOWED_EXCEPTIONS
:
1754 = add_ehspec_entry (ehspec
, ttypes
, r
->u
.allowed
.type_list
);
1762 htab_delete (ttypes
);
1763 htab_delete (ehspec
);
1767 build_post_landing_pads ()
1771 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1773 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
1776 /* Mind we don't process a region more than once. */
1777 if (!region
|| region
->region_number
!= i
)
1780 switch (region
->type
)
1783 /* ??? Collect the set of all non-overlapping catch handlers
1784 all the way up the chain until blocked by a cleanup. */
1785 /* ??? Outer try regions can share landing pads with inner
1786 try regions if the types are completely non-overlapping,
1787 and there are no intervening cleanups. */
1789 region
->post_landing_pad
= gen_label_rtx ();
1793 emit_label (region
->post_landing_pad
);
1795 /* ??? It is mighty inconvenient to call back into the
1796 switch statement generation code in expand_end_case.
1797 Rapid prototyping sez a sequence of ifs. */
1799 struct eh_region
*c
;
1800 for (c
= region
->u
.try.catch; c
; c
= c
->u
.catch.next_catch
)
1802 /* ??? _Unwind_ForcedUnwind wants no match here. */
1803 if (c
->u
.catch.type_list
== NULL
)
1804 emit_jump (c
->label
);
1807 /* Need for one cmp/jump per type caught. Each type
1808 list entry has a matching entry in the filter list
1809 (see assign_filter_values). */
1810 tree tp_node
= c
->u
.catch.type_list
;
1811 tree flt_node
= c
->u
.catch.filter_list
;
1815 emit_cmp_and_jump_insns
1817 GEN_INT (tree_low_cst (TREE_VALUE (flt_node
), 0)),
1818 EQ
, NULL_RTX
, word_mode
, 0, c
->label
);
1820 tp_node
= TREE_CHAIN (tp_node
);
1821 flt_node
= TREE_CHAIN (flt_node
);
1827 /* We delay the generation of the _Unwind_Resume until we generate
1828 landing pads. We emit a marker here so as to get good control
1829 flow data in the meantime. */
1831 = emit_jump_insn (gen_rtx_RESX (VOIDmode
, region
->region_number
));
1837 emit_insns_before (seq
, region
->u
.try.catch->label
);
1840 case ERT_ALLOWED_EXCEPTIONS
:
1841 region
->post_landing_pad
= gen_label_rtx ();
1845 emit_label (region
->post_landing_pad
);
1847 emit_cmp_and_jump_insns (cfun
->eh
->filter
,
1848 GEN_INT (region
->u
.allowed
.filter
),
1849 EQ
, NULL_RTX
, word_mode
, 0, region
->label
);
1851 /* We delay the generation of the _Unwind_Resume until we generate
1852 landing pads. We emit a marker here so as to get good control
1853 flow data in the meantime. */
1855 = emit_jump_insn (gen_rtx_RESX (VOIDmode
, region
->region_number
));
1861 emit_insns_before (seq
, region
->label
);
1865 case ERT_MUST_NOT_THROW
:
1866 region
->post_landing_pad
= region
->label
;
1871 /* Nothing to do. */
1880 /* Replace RESX patterns with jumps to the next handler if any, or calls to
1881 _Unwind_Resume otherwise. */
1884 connect_post_landing_pads ()
1888 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1890 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
1891 struct eh_region
*outer
;
1894 /* Mind we don't process a region more than once. */
1895 if (!region
|| region
->region_number
!= i
)
1898 /* If there is no RESX, or it has been deleted by flow, there's
1899 nothing to fix up. */
1900 if (! region
->resume
|| INSN_DELETED_P (region
->resume
))
1903 /* Search for another landing pad in this function. */
1904 for (outer
= region
->outer
; outer
; outer
= outer
->outer
)
1905 if (outer
->post_landing_pad
)
1911 emit_jump (outer
->post_landing_pad
);
1913 emit_library_call (unwind_resume_libfunc
, LCT_THROW
,
1914 VOIDmode
, 1, cfun
->eh
->exc_ptr
, Pmode
);
1918 emit_insns_before (seq
, region
->resume
);
1919 delete_insn (region
->resume
);
1925 dw2_build_landing_pads ()
1930 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
1932 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
1934 bool clobbers_hard_regs
= false;
1936 /* Mind we don't process a region more than once. */
1937 if (!region
|| region
->region_number
!= i
)
1940 if (region
->type
!= ERT_CLEANUP
1941 && region
->type
!= ERT_TRY
1942 && region
->type
!= ERT_ALLOWED_EXCEPTIONS
)
1947 region
->landing_pad
= gen_label_rtx ();
1948 emit_label (region
->landing_pad
);
1950 #ifdef HAVE_exception_receiver
1951 if (HAVE_exception_receiver
)
1952 emit_insn (gen_exception_receiver ());
1955 #ifdef HAVE_nonlocal_goto_receiver
1956 if (HAVE_nonlocal_goto_receiver
)
1957 emit_insn (gen_nonlocal_goto_receiver ());
1962 /* If the eh_return data registers are call-saved, then we
1963 won't have considered them clobbered from the call that
1964 threw. Kill them now. */
1967 unsigned r
= EH_RETURN_DATA_REGNO (j
);
1968 if (r
== INVALID_REGNUM
)
1970 if (! call_used_regs
[r
])
1972 emit_insn (gen_rtx_CLOBBER (VOIDmode
, gen_rtx_REG (Pmode
, r
)));
1973 clobbers_hard_regs
= true;
1977 if (clobbers_hard_regs
)
1979 /* @@@ This is a kludge. Not all machine descriptions define a
1980 blockage insn, but we must not allow the code we just generated
1981 to be reordered by scheduling. So emit an ASM_INPUT to act as
1983 emit_insn (gen_rtx_ASM_INPUT (VOIDmode
, ""));
1986 emit_move_insn (cfun
->eh
->exc_ptr
,
1987 gen_rtx_REG (Pmode
, EH_RETURN_DATA_REGNO (0)));
1988 emit_move_insn (cfun
->eh
->filter
,
1989 gen_rtx_REG (word_mode
, EH_RETURN_DATA_REGNO (1)));
1994 emit_insns_before (seq
, region
->post_landing_pad
);
2001 int directly_reachable
;
2004 int call_site_index
;
2008 sjlj_find_directly_reachable_regions (lp_info
)
2009 struct sjlj_lp_info
*lp_info
;
2012 bool found_one
= false;
2014 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
2016 struct eh_region
*region
;
2020 if (! INSN_P (insn
))
2023 note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
2024 if (!note
|| INTVAL (XEXP (note
, 0)) <= 0)
2027 region
= cfun
->eh
->region_array
[INTVAL (XEXP (note
, 0))];
2029 type_thrown
= NULL_TREE
;
2030 if (region
->type
== ERT_THROW
)
2032 type_thrown
= region
->u
.throw.type
;
2033 region
= region
->outer
;
2036 /* Find the first containing region that might handle the exception.
2037 That's the landing pad to which we will transfer control. */
2038 for (; region
; region
= region
->outer
)
2039 if (reachable_next_level (region
, type_thrown
, 0) != RNL_NOT_CAUGHT
)
2044 lp_info
[region
->region_number
].directly_reachable
= 1;
2053 sjlj_assign_call_site_values (dispatch_label
, lp_info
)
2055 struct sjlj_lp_info
*lp_info
;
2060 /* First task: build the action table. */
2062 VARRAY_UCHAR_INIT (cfun
->eh
->action_record_data
, 64, "action_record_data");
2063 ar_hash
= htab_create (31, action_record_hash
, action_record_eq
, free
);
2065 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
2066 if (lp_info
[i
].directly_reachable
)
2068 struct eh_region
*r
= cfun
->eh
->region_array
[i
];
2069 r
->landing_pad
= dispatch_label
;
2070 lp_info
[i
].action_index
= collect_one_action_chain (ar_hash
, r
);
2071 if (lp_info
[i
].action_index
!= -1)
2072 cfun
->uses_eh_lsda
= 1;
2075 htab_delete (ar_hash
);
2077 /* Next: assign dispatch values. In dwarf2 terms, this would be the
2078 landing pad label for the region. For sjlj though, there is one
2079 common landing pad from which we dispatch to the post-landing pads.
2081 A region receives a dispatch index if it is directly reachable
2082 and requires in-function processing. Regions that share post-landing
2083 pads may share dispatch indices. */
2084 /* ??? Post-landing pad sharing doesn't actually happen at the moment
2085 (see build_post_landing_pads) so we don't bother checking for it. */
2088 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
2089 if (lp_info
[i
].directly_reachable
2090 && lp_info
[i
].action_index
>= 0)
2091 lp_info
[i
].dispatch_index
= index
++;
2093 /* Finally: assign call-site values. If dwarf2 terms, this would be
2094 the region number assigned by convert_to_eh_region_ranges, but
2095 handles no-action and must-not-throw differently. */
2098 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
2099 if (lp_info
[i
].directly_reachable
)
2101 int action
= lp_info
[i
].action_index
;
2103 /* Map must-not-throw to otherwise unused call-site index 0. */
2106 /* Map no-action to otherwise unused call-site index -1. */
2107 else if (action
== -1)
2109 /* Otherwise, look it up in the table. */
2111 index
= add_call_site (GEN_INT (lp_info
[i
].dispatch_index
), action
);
2113 lp_info
[i
].call_site_index
= index
;
2118 sjlj_mark_call_sites (lp_info
)
2119 struct sjlj_lp_info
*lp_info
;
2121 int last_call_site
= -2;
2124 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
2126 struct eh_region
*region
;
2128 rtx note
, before
, p
;
2130 /* Reset value tracking at extended basic block boundaries. */
2131 if (GET_CODE (insn
) == CODE_LABEL
)
2132 last_call_site
= -2;
2134 if (! INSN_P (insn
))
2137 note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
2140 /* Calls (and trapping insns) without notes are outside any
2141 exception handling region in this function. Mark them as
2143 if (GET_CODE (insn
) == CALL_INSN
2144 || (flag_non_call_exceptions
2145 && may_trap_p (PATTERN (insn
))))
2146 this_call_site
= -1;
2152 /* Calls that are known to not throw need not be marked. */
2153 if (INTVAL (XEXP (note
, 0)) <= 0)
2156 region
= cfun
->eh
->region_array
[INTVAL (XEXP (note
, 0))];
2157 this_call_site
= lp_info
[region
->region_number
].call_site_index
;
2160 if (this_call_site
== last_call_site
)
2163 /* Don't separate a call from it's argument loads. */
2165 if (GET_CODE (insn
) == CALL_INSN
)
2166 before
= find_first_parameter_load (insn
, NULL_RTX
);
2169 mem
= adjust_address (cfun
->eh
->sjlj_fc
, TYPE_MODE (integer_type_node
),
2170 sjlj_fc_call_site_ofs
);
2171 emit_move_insn (mem
, GEN_INT (this_call_site
));
2175 emit_insns_before (p
, before
);
2176 last_call_site
= this_call_site
;
2180 /* Construct the SjLj_Function_Context. */
2183 sjlj_emit_function_enter (dispatch_label
)
2186 rtx fn_begin
, fc
, mem
, seq
;
2188 fc
= cfun
->eh
->sjlj_fc
;
2192 /* We're storing this libcall's address into memory instead of
2193 calling it directly. Thus, we must call assemble_external_libcall
2194 here, as we can not depend on emit_library_call to do it for us. */
2195 assemble_external_libcall (eh_personality_libfunc
);
2196 mem
= adjust_address (fc
, Pmode
, sjlj_fc_personality_ofs
);
2197 emit_move_insn (mem
, eh_personality_libfunc
);
2199 mem
= adjust_address (fc
, Pmode
, sjlj_fc_lsda_ofs
);
2200 if (cfun
->uses_eh_lsda
)
2203 ASM_GENERATE_INTERNAL_LABEL (buf
, "LLSDA", sjlj_funcdef_number
);
2204 emit_move_insn (mem
, gen_rtx_SYMBOL_REF (Pmode
, ggc_strdup (buf
)));
2207 emit_move_insn (mem
, const0_rtx
);
2209 #ifdef DONT_USE_BUILTIN_SETJMP
2212 x
= emit_library_call_value (setjmp_libfunc
, NULL_RTX
, LCT_RETURNS_TWICE
,
2213 TYPE_MODE (integer_type_node
), 1,
2214 plus_constant (XEXP (fc
, 0),
2215 sjlj_fc_jbuf_ofs
), Pmode
);
2217 note
= emit_note (NULL
, NOTE_INSN_EXPECTED_VALUE
);
2218 NOTE_EXPECTED_VALUE (note
) = gen_rtx_EQ (VOIDmode
, x
, const0_rtx
);
2220 emit_cmp_and_jump_insns (x
, const0_rtx
, NE
, 0,
2221 TYPE_MODE (integer_type_node
), 0, dispatch_label
);
2224 expand_builtin_setjmp_setup (plus_constant (XEXP (fc
, 0), sjlj_fc_jbuf_ofs
),
2228 emit_library_call (unwind_sjlj_register_libfunc
, LCT_NORMAL
, VOIDmode
,
2229 1, XEXP (fc
, 0), Pmode
);
2234 /* ??? Instead of doing this at the beginning of the function,
2235 do this in a block that is at loop level 0 and dominates all
2236 can_throw_internal instructions. */
2238 for (fn_begin
= get_insns (); ; fn_begin
= NEXT_INSN (fn_begin
))
2239 if (GET_CODE (fn_begin
) == NOTE
2240 && NOTE_LINE_NUMBER (fn_begin
) == NOTE_INSN_FUNCTION_BEG
)
2242 emit_insns_after (seq
, fn_begin
);
2245 /* Call back from expand_function_end to know where we should put
2246 the call to unwind_sjlj_unregister_libfunc if needed. */
2249 sjlj_emit_function_exit_after (after
)
2252 cfun
->eh
->sjlj_exit_after
= after
;
2256 sjlj_emit_function_exit ()
2262 emit_library_call (unwind_sjlj_unregister_libfunc
, LCT_NORMAL
, VOIDmode
,
2263 1, XEXP (cfun
->eh
->sjlj_fc
, 0), Pmode
);
2268 /* ??? Really this can be done in any block at loop level 0 that
2269 post-dominates all can_throw_internal instructions. This is
2270 the last possible moment. */
2272 emit_insns_after (seq
, cfun
->eh
->sjlj_exit_after
);
2276 sjlj_emit_dispatch_table (dispatch_label
, lp_info
)
2278 struct sjlj_lp_info
*lp_info
;
2280 int i
, first_reachable
;
2281 rtx mem
, dispatch
, seq
, fc
;
2283 fc
= cfun
->eh
->sjlj_fc
;
2287 emit_label (dispatch_label
);
2289 #ifndef DONT_USE_BUILTIN_SETJMP
2290 expand_builtin_setjmp_receiver (dispatch_label
);
2293 /* Load up dispatch index, exc_ptr and filter values from the
2294 function context. */
2295 mem
= adjust_address (fc
, TYPE_MODE (integer_type_node
),
2296 sjlj_fc_call_site_ofs
);
2297 dispatch
= copy_to_reg (mem
);
2299 mem
= adjust_address (fc
, word_mode
, sjlj_fc_data_ofs
);
2300 if (word_mode
!= Pmode
)
2302 #ifdef POINTERS_EXTEND_UNSIGNED
2303 mem
= convert_memory_address (Pmode
, mem
);
2305 mem
= convert_to_mode (Pmode
, mem
, 0);
2308 emit_move_insn (cfun
->eh
->exc_ptr
, mem
);
2310 mem
= adjust_address (fc
, word_mode
, sjlj_fc_data_ofs
+ UNITS_PER_WORD
);
2311 emit_move_insn (cfun
->eh
->filter
, mem
);
2313 /* Jump to one of the directly reachable regions. */
2314 /* ??? This really ought to be using a switch statement. */
2316 first_reachable
= 0;
2317 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
2319 if (! lp_info
[i
].directly_reachable
2320 || lp_info
[i
].action_index
< 0)
2323 if (! first_reachable
)
2325 first_reachable
= i
;
2329 emit_cmp_and_jump_insns (dispatch
, GEN_INT (lp_info
[i
].dispatch_index
),
2330 EQ
, NULL_RTX
, TYPE_MODE (integer_type_node
), 0,
2331 cfun
->eh
->region_array
[i
]->post_landing_pad
);
2337 emit_insns_before (seq
, (cfun
->eh
->region_array
[first_reachable
]
2338 ->post_landing_pad
));
2342 sjlj_build_landing_pads ()
2344 struct sjlj_lp_info
*lp_info
;
2346 lp_info
= (struct sjlj_lp_info
*) xcalloc (cfun
->eh
->last_region_number
+ 1,
2347 sizeof (struct sjlj_lp_info
));
2349 if (sjlj_find_directly_reachable_regions (lp_info
))
2351 rtx dispatch_label
= gen_label_rtx ();
2354 = assign_stack_local (TYPE_MODE (sjlj_fc_type_node
),
2355 int_size_in_bytes (sjlj_fc_type_node
),
2356 TYPE_ALIGN (sjlj_fc_type_node
));
2358 sjlj_assign_call_site_values (dispatch_label
, lp_info
);
2359 sjlj_mark_call_sites (lp_info
);
2361 sjlj_emit_function_enter (dispatch_label
);
2362 sjlj_emit_dispatch_table (dispatch_label
, lp_info
);
2363 sjlj_emit_function_exit ();
2370 finish_eh_generation ()
2372 /* Nothing to do if no regions created. */
2373 if (cfun
->eh
->region_tree
== NULL
)
2376 /* The object here is to provide find_basic_blocks with detailed
2377 information (via reachable_handlers) on how exception control
2378 flows within the function. In this first pass, we can include
2379 type information garnered from ERT_THROW and ERT_ALLOWED_EXCEPTIONS
2380 regions, and hope that it will be useful in deleting unreachable
2381 handlers. Subsequently, we will generate landing pads which will
2382 connect many of the handlers, and then type information will not
2383 be effective. Still, this is a win over previous implementations. */
2385 rebuild_jump_labels (get_insns ());
2386 find_basic_blocks (get_insns (), max_reg_num (), 0);
2387 cleanup_cfg (CLEANUP_PRE_LOOP
);
2389 /* These registers are used by the landing pads. Make sure they
2390 have been generated. */
2391 get_exception_pointer (cfun
);
2392 get_exception_filter (cfun
);
2394 /* Construct the landing pads. */
2396 assign_filter_values ();
2397 build_post_landing_pads ();
2398 connect_post_landing_pads ();
2399 if (USING_SJLJ_EXCEPTIONS
)
2400 sjlj_build_landing_pads ();
2402 dw2_build_landing_pads ();
2404 cfun
->eh
->built_landing_pads
= 1;
2406 /* We've totally changed the CFG. Start over. */
2407 find_exception_handler_labels ();
2408 rebuild_jump_labels (get_insns ());
2409 find_basic_blocks (get_insns (), max_reg_num (), 0);
2410 cleanup_cfg (CLEANUP_PRE_LOOP
);
2413 /* This section handles removing dead code for flow. */
2415 /* Remove LABEL from the exception_handler_labels list. */
2418 remove_exception_handler_label (label
)
2423 for (pl
= &exception_handler_labels
, l
= *pl
;
2424 XEXP (l
, 0) != label
;
2425 pl
= &XEXP (l
, 1), l
= *pl
)
2429 free_EXPR_LIST_node (l
);
2432 /* Splice REGION from the region tree etc. */
2435 remove_eh_handler (region
)
2436 struct eh_region
*region
;
2438 struct eh_region
**pp
, *p
;
2442 /* For the benefit of efficiently handling REG_EH_REGION notes,
2443 replace this region in the region array with its containing
2444 region. Note that previous region deletions may result in
2445 multiple copies of this region in the array, so we have to
2446 search the whole thing. */
2447 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
2448 if (cfun
->eh
->region_array
[i
] == region
)
2449 cfun
->eh
->region_array
[i
] = region
->outer
;
2451 if (cfun
->eh
->built_landing_pads
)
2452 lab
= region
->landing_pad
;
2454 lab
= region
->label
;
2456 remove_exception_handler_label (lab
);
2459 pp
= ®ion
->outer
->inner
;
2461 pp
= &cfun
->eh
->region_tree
;
2462 for (p
= *pp
; p
!= region
; pp
= &p
->next_peer
, p
= *pp
)
2467 for (p
= region
->inner
; p
->next_peer
; p
= p
->next_peer
)
2468 p
->outer
= region
->outer
;
2469 p
->next_peer
= region
->next_peer
;
2470 p
->outer
= region
->outer
;
2471 *pp
= region
->inner
;
2474 *pp
= region
->next_peer
;
2476 if (region
->type
== ERT_CATCH
)
2478 struct eh_region
*try, *next
, *prev
;
2480 for (try = region
->next_peer
;
2481 try->type
== ERT_CATCH
;
2482 try = try->next_peer
)
2484 if (try->type
!= ERT_TRY
)
2487 next
= region
->u
.catch.next_catch
;
2488 prev
= region
->u
.catch.prev_catch
;
2491 next
->u
.catch.prev_catch
= prev
;
2493 try->u
.try.last_catch
= prev
;
2495 prev
->u
.catch.next_catch
= next
;
2498 try->u
.try.catch = next
;
2500 remove_eh_handler (try);
2507 /* LABEL heads a basic block that is about to be deleted. If this
2508 label corresponds to an exception region, we may be able to
2509 delete the region. */
2512 maybe_remove_eh_handler (label
)
2517 /* ??? After generating landing pads, it's not so simple to determine
2518 if the region data is completely unused. One must examine the
2519 landing pad and the post landing pad, and whether an inner try block
2520 is referencing the catch handlers directly. */
2521 if (cfun
->eh
->built_landing_pads
)
2524 for (i
= cfun
->eh
->last_region_number
; i
> 0; --i
)
2526 struct eh_region
*region
= cfun
->eh
->region_array
[i
];
2527 if (region
&& region
->label
== label
)
2529 /* Flow will want to remove MUST_NOT_THROW regions as unreachable
2530 because there is no path to the fallback call to terminate.
2531 But the region continues to affect call-site data until there
2532 are no more contained calls, which we don't see here. */
2533 if (region
->type
== ERT_MUST_NOT_THROW
)
2535 remove_exception_handler_label (region
->label
);
2536 region
->label
= NULL_RTX
;
2539 remove_eh_handler (region
);
2546 /* This section describes CFG exception edges for flow. */
2548 /* For communicating between calls to reachable_next_level. */
2549 struct reachable_info
2556 /* A subroutine of reachable_next_level. Return true if TYPE, or a
2557 base class of TYPE, is in HANDLED. */
2560 check_handled (handled
, type
)
2565 /* We can check for exact matches without front-end help. */
2566 if (! lang_eh_type_covers
)
2568 for (t
= handled
; t
; t
= TREE_CHAIN (t
))
2569 if (TREE_VALUE (t
) == type
)
2574 for (t
= handled
; t
; t
= TREE_CHAIN (t
))
2575 if ((*lang_eh_type_covers
) (TREE_VALUE (t
), type
))
2582 /* A subroutine of reachable_next_level. If we are collecting a list
2583 of handlers, add one. After landing pad generation, reference
2584 it instead of the handlers themselves. Further, the handlers are
2585 all wired together, so by referencing one, we've got them all.
2586 Before landing pad generation we reference each handler individually.
2588 LP_REGION contains the landing pad; REGION is the handler. */
2591 add_reachable_handler (info
, lp_region
, region
)
2592 struct reachable_info
*info
;
2593 struct eh_region
*lp_region
;
2594 struct eh_region
*region
;
2599 if (cfun
->eh
->built_landing_pads
)
2601 if (! info
->handlers
)
2602 info
->handlers
= alloc_INSN_LIST (lp_region
->landing_pad
, NULL_RTX
);
2605 info
->handlers
= alloc_INSN_LIST (region
->label
, info
->handlers
);
2608 /* Process one level of exception regions for reachability.
2609 If TYPE_THROWN is non-null, then it is the *exact* type being
2610 propagated. If INFO is non-null, then collect handler labels
2611 and caught/allowed type information between invocations. */
2613 static enum reachable_code
2614 reachable_next_level (region
, type_thrown
, info
)
2615 struct eh_region
*region
;
2617 struct reachable_info
*info
;
2619 switch (region
->type
)
2622 /* Before landing-pad generation, we model control flow
2623 directly to the individual handlers. In this way we can
2624 see that catch handler types may shadow one another. */
2625 add_reachable_handler (info
, region
, region
);
2626 return RNL_MAYBE_CAUGHT
;
2630 struct eh_region
*c
;
2631 enum reachable_code ret
= RNL_NOT_CAUGHT
;
2633 for (c
= region
->u
.try.catch; c
; c
= c
->u
.catch.next_catch
)
2635 /* A catch-all handler ends the search. */
2636 /* ??? _Unwind_ForcedUnwind will want outer cleanups
2637 to be run as well. */
2638 if (c
->u
.catch.type_list
== NULL
)
2640 add_reachable_handler (info
, region
, c
);
2646 /* If we have a at least one type match, end the search. */
2647 tree tp_node
= c
->u
.catch.type_list
;
2649 for (; tp_node
; tp_node
= TREE_CHAIN (tp_node
))
2651 tree type
= TREE_VALUE (tp_node
);
2653 if (type
== type_thrown
2654 || (lang_eh_type_covers
2655 && (*lang_eh_type_covers
) (type
, type_thrown
)))
2657 add_reachable_handler (info
, region
, c
);
2662 /* If we have definitive information of a match failure,
2663 the catch won't trigger. */
2664 if (lang_eh_type_covers
)
2665 return RNL_NOT_CAUGHT
;
2668 /* At this point, we either don't know what type is thrown or
2669 don't have front-end assistance to help deciding if it is
2670 covered by one of the types in the list for this region.
2672 We'd then like to add this region to the list of reachable
2673 handlers since it is indeed potentially reachable based on the
2674 information we have.
2676 Actually, this handler is for sure not reachable if all the
2677 types it matches have already been caught. That is, it is only
2678 potentially reachable if at least one of the types it catches
2679 has not been previously caught. */
2682 ret
= RNL_MAYBE_CAUGHT
;
2685 tree tp_node
= c
->u
.catch.type_list
;
2686 bool maybe_reachable
= false;
2688 /* Compute the potential reachability of this handler and
2689 update the list of types caught at the same time. */
2690 for (; tp_node
; tp_node
= TREE_CHAIN (tp_node
))
2692 tree type
= TREE_VALUE (tp_node
);
2694 if (! check_handled (info
->types_caught
, type
))
2697 = tree_cons (NULL
, type
, info
->types_caught
);
2699 maybe_reachable
= true;
2703 if (maybe_reachable
)
2705 add_reachable_handler (info
, region
, c
);
2707 /* ??? If the catch type is a base class of every allowed
2708 type, then we know we can stop the search. */
2709 ret
= RNL_MAYBE_CAUGHT
;
2717 case ERT_ALLOWED_EXCEPTIONS
:
2718 /* An empty list of types definitely ends the search. */
2719 if (region
->u
.allowed
.type_list
== NULL_TREE
)
2721 add_reachable_handler (info
, region
, region
);
2725 /* Collect a list of lists of allowed types for use in detecting
2726 when a catch may be transformed into a catch-all. */
2728 info
->types_allowed
= tree_cons (NULL_TREE
,
2729 region
->u
.allowed
.type_list
,
2730 info
->types_allowed
);
2732 /* If we have definitive information about the type hierarchy,
2733 then we can tell if the thrown type will pass through the
2735 if (type_thrown
&& lang_eh_type_covers
)
2737 if (check_handled (region
->u
.allowed
.type_list
, type_thrown
))
2738 return RNL_NOT_CAUGHT
;
2741 add_reachable_handler (info
, region
, region
);
2746 add_reachable_handler (info
, region
, region
);
2747 return RNL_MAYBE_CAUGHT
;
2750 /* Catch regions are handled by their controling try region. */
2751 return RNL_NOT_CAUGHT
;
2753 case ERT_MUST_NOT_THROW
:
2754 /* Here we end our search, since no exceptions may propagate.
2755 If we've touched down at some landing pad previous, then the
2756 explicit function call we generated may be used. Otherwise
2757 the call is made by the runtime. */
2758 if (info
&& info
->handlers
)
2760 add_reachable_handler (info
, region
, region
);
2768 /* Shouldn't see these here. */
2775 /* Retrieve a list of labels of exception handlers which can be
2776 reached by a given insn. */
2779 reachable_handlers (insn
)
2782 struct reachable_info info
;
2783 struct eh_region
*region
;
2787 if (GET_CODE (insn
) == JUMP_INSN
2788 && GET_CODE (PATTERN (insn
)) == RESX
)
2789 region_number
= XINT (PATTERN (insn
), 0);
2792 rtx note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
2793 if (!note
|| INTVAL (XEXP (note
, 0)) <= 0)
2795 region_number
= INTVAL (XEXP (note
, 0));
2798 memset (&info
, 0, sizeof (info
));
2800 region
= cfun
->eh
->region_array
[region_number
];
2802 type_thrown
= NULL_TREE
;
2803 if (GET_CODE (insn
) == JUMP_INSN
2804 && GET_CODE (PATTERN (insn
)) == RESX
)
2806 /* A RESX leaves a region instead of entering it. Thus the
2807 region itself may have been deleted out from under us. */
2810 region
= region
->outer
;
2812 else if (region
->type
== ERT_THROW
)
2814 type_thrown
= region
->u
.throw.type
;
2815 region
= region
->outer
;
2818 for (; region
; region
= region
->outer
)
2819 if (reachable_next_level (region
, type_thrown
, &info
) >= RNL_CAUGHT
)
2822 return info
.handlers
;
2825 /* Determine if the given INSN can throw an exception that is caught
2826 within the function. */
2829 can_throw_internal (insn
)
2832 struct eh_region
*region
;
2836 if (! INSN_P (insn
))
2839 if (GET_CODE (insn
) == INSN
2840 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
2841 insn
= XVECEXP (PATTERN (insn
), 0, 0);
2843 if (GET_CODE (insn
) == CALL_INSN
2844 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
2847 for (i
= 0; i
< 3; ++i
)
2849 rtx sub
= XEXP (PATTERN (insn
), i
);
2850 for (; sub
; sub
= NEXT_INSN (sub
))
2851 if (can_throw_internal (sub
))
2857 /* Every insn that might throw has an EH_REGION note. */
2858 note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
2859 if (!note
|| INTVAL (XEXP (note
, 0)) <= 0)
2862 region
= cfun
->eh
->region_array
[INTVAL (XEXP (note
, 0))];
2864 type_thrown
= NULL_TREE
;
2865 if (region
->type
== ERT_THROW
)
2867 type_thrown
= region
->u
.throw.type
;
2868 region
= region
->outer
;
2871 /* If this exception is ignored by each and every containing region,
2872 then control passes straight out. The runtime may handle some
2873 regions, which also do not require processing internally. */
2874 for (; region
; region
= region
->outer
)
2876 enum reachable_code how
= reachable_next_level (region
, type_thrown
, 0);
2877 if (how
== RNL_BLOCKED
)
2879 if (how
!= RNL_NOT_CAUGHT
)
2886 /* Determine if the given INSN can throw an exception that is
2887 visible outside the function. */
2890 can_throw_external (insn
)
2893 struct eh_region
*region
;
2897 if (! INSN_P (insn
))
2900 if (GET_CODE (insn
) == INSN
2901 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
2902 insn
= XVECEXP (PATTERN (insn
), 0, 0);
2904 if (GET_CODE (insn
) == CALL_INSN
2905 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
2908 for (i
= 0; i
< 3; ++i
)
2910 rtx sub
= XEXP (PATTERN (insn
), i
);
2911 for (; sub
; sub
= NEXT_INSN (sub
))
2912 if (can_throw_external (sub
))
2918 note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
2921 /* Calls (and trapping insns) without notes are outside any
2922 exception handling region in this function. We have to
2923 assume it might throw. Given that the front end and middle
2924 ends mark known NOTHROW functions, this isn't so wildly
2926 return (GET_CODE (insn
) == CALL_INSN
2927 || (flag_non_call_exceptions
2928 && may_trap_p (PATTERN (insn
))));
2930 if (INTVAL (XEXP (note
, 0)) <= 0)
2933 region
= cfun
->eh
->region_array
[INTVAL (XEXP (note
, 0))];
2935 type_thrown
= NULL_TREE
;
2936 if (region
->type
== ERT_THROW
)
2938 type_thrown
= region
->u
.throw.type
;
2939 region
= region
->outer
;
2942 /* If the exception is caught or blocked by any containing region,
2943 then it is not seen by any calling function. */
2944 for (; region
; region
= region
->outer
)
2945 if (reachable_next_level (region
, type_thrown
, NULL
) >= RNL_CAUGHT
)
2951 /* True if nothing in this function can throw outside this function. */
2954 nothrow_function_p ()
2958 if (! flag_exceptions
)
2961 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
2962 if (can_throw_external (insn
))
2964 for (insn
= current_function_epilogue_delay_list
; insn
;
2965 insn
= XEXP (insn
, 1))
2966 if (can_throw_external (insn
))
2973 /* Various hooks for unwind library. */
2975 /* Do any necessary initialization to access arbitrary stack frames.
2976 On the SPARC, this means flushing the register windows. */
2979 expand_builtin_unwind_init ()
2981 /* Set this so all the registers get saved in our frame; we need to be
2982 able to copy the saved values for any registers from frames we unwind. */
2983 current_function_has_nonlocal_label
= 1;
2985 #ifdef SETUP_FRAME_ADDRESSES
2986 SETUP_FRAME_ADDRESSES ();
2991 expand_builtin_eh_return_data_regno (arglist
)
2994 tree which
= TREE_VALUE (arglist
);
2995 unsigned HOST_WIDE_INT iwhich
;
2997 if (TREE_CODE (which
) != INTEGER_CST
)
2999 error ("argument of `__builtin_eh_return_regno' must be constant");
3003 iwhich
= tree_low_cst (which
, 1);
3004 iwhich
= EH_RETURN_DATA_REGNO (iwhich
);
3005 if (iwhich
== INVALID_REGNUM
)
3008 #ifdef DWARF_FRAME_REGNUM
3009 iwhich
= DWARF_FRAME_REGNUM (iwhich
);
3011 iwhich
= DBX_REGISTER_NUMBER (iwhich
);
3014 return GEN_INT (iwhich
);
3017 /* Given a value extracted from the return address register or stack slot,
3018 return the actual address encoded in that value. */
3021 expand_builtin_extract_return_addr (addr_tree
)
3024 rtx addr
= expand_expr (addr_tree
, NULL_RTX
, Pmode
, 0);
3026 /* First mask out any unwanted bits. */
3027 #ifdef MASK_RETURN_ADDR
3028 expand_and (addr
, MASK_RETURN_ADDR
, addr
);
3031 /* Then adjust to find the real return address. */
3032 #if defined (RETURN_ADDR_OFFSET)
3033 addr
= plus_constant (addr
, RETURN_ADDR_OFFSET
);
3039 /* Given an actual address in addr_tree, do any necessary encoding
3040 and return the value to be stored in the return address register or
3041 stack slot so the epilogue will return to that address. */
3044 expand_builtin_frob_return_addr (addr_tree
)
3047 rtx addr
= expand_expr (addr_tree
, NULL_RTX
, ptr_mode
, 0);
3049 #ifdef POINTERS_EXTEND_UNSIGNED
3050 if (GET_MODE (addr
) != Pmode
)
3051 addr
= convert_memory_address (Pmode
, addr
);
3054 #ifdef RETURN_ADDR_OFFSET
3055 addr
= force_reg (Pmode
, addr
);
3056 addr
= plus_constant (addr
, -RETURN_ADDR_OFFSET
);
3062 /* Set up the epilogue with the magic bits we'll need to return to the
3063 exception handler. */
3066 expand_builtin_eh_return (stackadj_tree
, handler_tree
)
3067 tree stackadj_tree
, handler_tree
;
3069 rtx stackadj
, handler
;
3071 stackadj
= expand_expr (stackadj_tree
, cfun
->eh
->ehr_stackadj
, VOIDmode
, 0);
3072 handler
= expand_expr (handler_tree
, cfun
->eh
->ehr_handler
, VOIDmode
, 0);
3074 #ifdef POINTERS_EXTEND_UNSIGNED
3075 if (GET_MODE (stackadj
) != Pmode
)
3076 stackadj
= convert_memory_address (Pmode
, stackadj
);
3078 if (GET_MODE (handler
) != Pmode
)
3079 handler
= convert_memory_address (Pmode
, handler
);
3082 if (! cfun
->eh
->ehr_label
)
3084 cfun
->eh
->ehr_stackadj
= copy_to_reg (stackadj
);
3085 cfun
->eh
->ehr_handler
= copy_to_reg (handler
);
3086 cfun
->eh
->ehr_label
= gen_label_rtx ();
3090 if (stackadj
!= cfun
->eh
->ehr_stackadj
)
3091 emit_move_insn (cfun
->eh
->ehr_stackadj
, stackadj
);
3092 if (handler
!= cfun
->eh
->ehr_handler
)
3093 emit_move_insn (cfun
->eh
->ehr_handler
, handler
);
3096 emit_jump (cfun
->eh
->ehr_label
);
3102 rtx sa
, ra
, around_label
;
3104 if (! cfun
->eh
->ehr_label
)
3107 sa
= EH_RETURN_STACKADJ_RTX
;
3110 error ("__builtin_eh_return not supported on this target");
3114 current_function_calls_eh_return
= 1;
3116 around_label
= gen_label_rtx ();
3117 emit_move_insn (sa
, const0_rtx
);
3118 emit_jump (around_label
);
3120 emit_label (cfun
->eh
->ehr_label
);
3121 clobber_return_register ();
3123 #ifdef HAVE_eh_return
3125 emit_insn (gen_eh_return (cfun
->eh
->ehr_stackadj
, cfun
->eh
->ehr_handler
));
3129 ra
= EH_RETURN_HANDLER_RTX
;
3132 error ("__builtin_eh_return not supported on this target");
3133 ra
= gen_reg_rtx (Pmode
);
3136 emit_move_insn (sa
, cfun
->eh
->ehr_stackadj
);
3137 emit_move_insn (ra
, cfun
->eh
->ehr_handler
);
3140 emit_label (around_label
);
3143 /* In the following functions, we represent entries in the action table
3144 as 1-based indices. Special cases are:
3146 0: null action record, non-null landing pad; implies cleanups
3147 -1: null action record, null landing pad; implies no action
3148 -2: no call-site entry; implies must_not_throw
3149 -3: we have yet to process outer regions
3151 Further, no special cases apply to the "next" field of the record.
3152 For next, 0 means end of list. */
3154 struct action_record
3162 action_record_eq (pentry
, pdata
)
3166 const struct action_record
*entry
= (const struct action_record
*) pentry
;
3167 const struct action_record
*data
= (const struct action_record
*) pdata
;
3168 return entry
->filter
== data
->filter
&& entry
->next
== data
->next
;
3172 action_record_hash (pentry
)
3175 const struct action_record
*entry
= (const struct action_record
*) pentry
;
3176 return entry
->next
* 1009 + entry
->filter
;
3180 add_action_record (ar_hash
, filter
, next
)
3184 struct action_record
**slot
, *new, tmp
;
3186 tmp
.filter
= filter
;
3188 slot
= (struct action_record
**) htab_find_slot (ar_hash
, &tmp
, INSERT
);
3190 if ((new = *slot
) == NULL
)
3192 new = (struct action_record
*) xmalloc (sizeof (*new));
3193 new->offset
= VARRAY_ACTIVE_SIZE (cfun
->eh
->action_record_data
) + 1;
3194 new->filter
= filter
;
3198 /* The filter value goes in untouched. The link to the next
3199 record is a "self-relative" byte offset, or zero to indicate
3200 that there is no next record. So convert the absolute 1 based
3201 indices we've been carrying around into a displacement. */
3203 push_sleb128 (&cfun
->eh
->action_record_data
, filter
);
3205 next
-= VARRAY_ACTIVE_SIZE (cfun
->eh
->action_record_data
) + 1;
3206 push_sleb128 (&cfun
->eh
->action_record_data
, next
);
3213 collect_one_action_chain (ar_hash
, region
)
3215 struct eh_region
*region
;
3217 struct eh_region
*c
;
3220 /* If we've reached the top of the region chain, then we have
3221 no actions, and require no landing pad. */
3225 switch (region
->type
)
3228 /* A cleanup adds a zero filter to the beginning of the chain, but
3229 there are special cases to look out for. If there are *only*
3230 cleanups along a path, then it compresses to a zero action.
3231 Further, if there are multiple cleanups along a path, we only
3232 need to represent one of them, as that is enough to trigger
3233 entry to the landing pad at runtime. */
3234 next
= collect_one_action_chain (ar_hash
, region
->outer
);
3237 for (c
= region
->outer
; c
; c
= c
->outer
)
3238 if (c
->type
== ERT_CLEANUP
)
3240 return add_action_record (ar_hash
, 0, next
);
3243 /* Process the associated catch regions in reverse order.
3244 If there's a catch-all handler, then we don't need to
3245 search outer regions. Use a magic -3 value to record
3246 that we haven't done the outer search. */
3248 for (c
= region
->u
.try.last_catch
; c
; c
= c
->u
.catch.prev_catch
)
3250 if (c
->u
.catch.type_list
== NULL
)
3252 /* Retrieve the filter from the head of the filter list
3253 where we have stored it (see assign_filter_values). */
3255 = TREE_INT_CST_LOW (TREE_VALUE (c
->u
.catch.filter_list
));
3257 next
= add_action_record (ar_hash
, filter
, 0);
3261 /* Once the outer search is done, trigger an action record for
3262 each filter we have. */
3267 next
= collect_one_action_chain (ar_hash
, region
->outer
);
3269 /* If there is no next action, terminate the chain. */
3272 /* If all outer actions are cleanups or must_not_throw,
3273 we'll have no action record for it, since we had wanted
3274 to encode these states in the call-site record directly.
3275 Add a cleanup action to the chain to catch these. */
3277 next
= add_action_record (ar_hash
, 0, 0);
3280 flt_node
= c
->u
.catch.filter_list
;
3281 for (; flt_node
; flt_node
= TREE_CHAIN (flt_node
))
3283 int filter
= TREE_INT_CST_LOW (TREE_VALUE (flt_node
));
3284 next
= add_action_record (ar_hash
, filter
, next
);
3290 case ERT_ALLOWED_EXCEPTIONS
:
3291 /* An exception specification adds its filter to the
3292 beginning of the chain. */
3293 next
= collect_one_action_chain (ar_hash
, region
->outer
);
3294 return add_action_record (ar_hash
, region
->u
.allowed
.filter
,
3295 next
< 0 ? 0 : next
);
3297 case ERT_MUST_NOT_THROW
:
3298 /* A must-not-throw region with no inner handlers or cleanups
3299 requires no call-site entry. Note that this differs from
3300 the no handler or cleanup case in that we do require an lsda
3301 to be generated. Return a magic -2 value to record this. */
3306 /* CATCH regions are handled in TRY above. THROW regions are
3307 for optimization information only and produce no output. */
3308 return collect_one_action_chain (ar_hash
, region
->outer
);
3316 add_call_site (landing_pad
, action
)
3320 struct call_site_record
*data
= cfun
->eh
->call_site_data
;
3321 int used
= cfun
->eh
->call_site_data_used
;
3322 int size
= cfun
->eh
->call_site_data_size
;
3326 size
= (size
? size
* 2 : 64);
3327 data
= (struct call_site_record
*)
3328 xrealloc (data
, sizeof (*data
) * size
);
3329 cfun
->eh
->call_site_data
= data
;
3330 cfun
->eh
->call_site_data_size
= size
;
3333 data
[used
].landing_pad
= landing_pad
;
3334 data
[used
].action
= action
;
3336 cfun
->eh
->call_site_data_used
= used
+ 1;
3338 return used
+ call_site_base
;
3341 /* Turn REG_EH_REGION notes back into NOTE_INSN_EH_REGION notes.
3342 The new note numbers will not refer to region numbers, but
3343 instead to call site entries. */
3346 convert_to_eh_region_ranges ()
3348 rtx insn
, iter
, note
;
3350 int last_action
= -3;
3351 rtx last_action_insn
= NULL_RTX
;
3352 rtx last_landing_pad
= NULL_RTX
;
3353 rtx first_no_action_insn
= NULL_RTX
;
3356 if (USING_SJLJ_EXCEPTIONS
|| cfun
->eh
->region_tree
== NULL
)
3359 VARRAY_UCHAR_INIT (cfun
->eh
->action_record_data
, 64, "action_record_data");
3361 ar_hash
= htab_create (31, action_record_hash
, action_record_eq
, free
);
3363 for (iter
= get_insns (); iter
; iter
= NEXT_INSN (iter
))
3366 struct eh_region
*region
;
3368 rtx this_landing_pad
;
3371 if (GET_CODE (insn
) == INSN
3372 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
3373 insn
= XVECEXP (PATTERN (insn
), 0, 0);
3375 note
= find_reg_note (insn
, REG_EH_REGION
, NULL_RTX
);
3378 if (! (GET_CODE (insn
) == CALL_INSN
3379 || (flag_non_call_exceptions
3380 && may_trap_p (PATTERN (insn
)))))
3387 if (INTVAL (XEXP (note
, 0)) <= 0)
3389 region
= cfun
->eh
->region_array
[INTVAL (XEXP (note
, 0))];
3390 this_action
= collect_one_action_chain (ar_hash
, region
);
3393 /* Existence of catch handlers, or must-not-throw regions
3394 implies that an lsda is needed (even if empty). */
3395 if (this_action
!= -1)
3396 cfun
->uses_eh_lsda
= 1;
3398 /* Delay creation of region notes for no-action regions
3399 until we're sure that an lsda will be required. */
3400 else if (last_action
== -3)
3402 first_no_action_insn
= iter
;
3406 /* Cleanups and handlers may share action chains but not
3407 landing pads. Collect the landing pad for this region. */
3408 if (this_action
>= 0)
3410 struct eh_region
*o
;
3411 for (o
= region
; ! o
->landing_pad
; o
= o
->outer
)
3413 this_landing_pad
= o
->landing_pad
;
3416 this_landing_pad
= NULL_RTX
;
3418 /* Differing actions or landing pads implies a change in call-site
3419 info, which implies some EH_REGION note should be emitted. */
3420 if (last_action
!= this_action
3421 || last_landing_pad
!= this_landing_pad
)
3423 /* If we'd not seen a previous action (-3) or the previous
3424 action was must-not-throw (-2), then we do not need an
3426 if (last_action
>= -1)
3428 /* If we delayed the creation of the begin, do it now. */
3429 if (first_no_action_insn
)
3431 call_site
= add_call_site (NULL_RTX
, 0);
3432 note
= emit_note_before (NOTE_INSN_EH_REGION_BEG
,
3433 first_no_action_insn
);
3434 NOTE_EH_HANDLER (note
) = call_site
;
3435 first_no_action_insn
= NULL_RTX
;
3438 note
= emit_note_after (NOTE_INSN_EH_REGION_END
,
3440 NOTE_EH_HANDLER (note
) = call_site
;
3443 /* If the new action is must-not-throw, then no region notes
3445 if (this_action
>= -1)
3447 call_site
= add_call_site (this_landing_pad
,
3448 this_action
< 0 ? 0 : this_action
);
3449 note
= emit_note_before (NOTE_INSN_EH_REGION_BEG
, iter
);
3450 NOTE_EH_HANDLER (note
) = call_site
;
3453 last_action
= this_action
;
3454 last_landing_pad
= this_landing_pad
;
3456 last_action_insn
= iter
;
3459 if (last_action
>= -1 && ! first_no_action_insn
)
3461 note
= emit_note_after (NOTE_INSN_EH_REGION_END
, last_action_insn
);
3462 NOTE_EH_HANDLER (note
) = call_site
;
3465 htab_delete (ar_hash
);
3470 push_uleb128 (data_area
, value
)
3471 varray_type
*data_area
;
3476 unsigned char byte
= value
& 0x7f;
3480 VARRAY_PUSH_UCHAR (*data_area
, byte
);
3486 push_sleb128 (data_area
, value
)
3487 varray_type
*data_area
;
3495 byte
= value
& 0x7f;
3497 more
= ! ((value
== 0 && (byte
& 0x40) == 0)
3498 || (value
== -1 && (byte
& 0x40) != 0));
3501 VARRAY_PUSH_UCHAR (*data_area
, byte
);
3507 #ifndef HAVE_AS_LEB128
3509 dw2_size_of_call_site_table ()
3511 int n
= cfun
->eh
->call_site_data_used
;
3512 int size
= n
* (4 + 4 + 4);
3515 for (i
= 0; i
< n
; ++i
)
3517 struct call_site_record
*cs
= &cfun
->eh
->call_site_data
[i
];
3518 size
+= size_of_uleb128 (cs
->action
);
3525 sjlj_size_of_call_site_table ()
3527 int n
= cfun
->eh
->call_site_data_used
;
3531 for (i
= 0; i
< n
; ++i
)
3533 struct call_site_record
*cs
= &cfun
->eh
->call_site_data
[i
];
3534 size
+= size_of_uleb128 (INTVAL (cs
->landing_pad
));
3535 size
+= size_of_uleb128 (cs
->action
);
3543 dw2_output_call_site_table ()
3545 const char *const function_start_lab
3546 = IDENTIFIER_POINTER (current_function_func_begin_label
);
3547 int n
= cfun
->eh
->call_site_data_used
;
3550 for (i
= 0; i
< n
; ++i
)
3552 struct call_site_record
*cs
= &cfun
->eh
->call_site_data
[i
];
3553 char reg_start_lab
[32];
3554 char reg_end_lab
[32];
3555 char landing_pad_lab
[32];
3557 ASM_GENERATE_INTERNAL_LABEL (reg_start_lab
, "LEHB", call_site_base
+ i
);
3558 ASM_GENERATE_INTERNAL_LABEL (reg_end_lab
, "LEHE", call_site_base
+ i
);
3560 if (cs
->landing_pad
)
3561 ASM_GENERATE_INTERNAL_LABEL (landing_pad_lab
, "L",
3562 CODE_LABEL_NUMBER (cs
->landing_pad
));
3564 /* ??? Perhaps use insn length scaling if the assembler supports
3565 generic arithmetic. */
3566 /* ??? Perhaps use attr_length to choose data1 or data2 instead of
3567 data4 if the function is small enough. */
3568 #ifdef HAVE_AS_LEB128
3569 dw2_asm_output_delta_uleb128 (reg_start_lab
, function_start_lab
,
3570 "region %d start", i
);
3571 dw2_asm_output_delta_uleb128 (reg_end_lab
, reg_start_lab
,
3573 if (cs
->landing_pad
)
3574 dw2_asm_output_delta_uleb128 (landing_pad_lab
, function_start_lab
,
3577 dw2_asm_output_data_uleb128 (0, "landing pad");
3579 dw2_asm_output_delta (4, reg_start_lab
, function_start_lab
,
3580 "region %d start", i
);
3581 dw2_asm_output_delta (4, reg_end_lab
, reg_start_lab
, "length");
3582 if (cs
->landing_pad
)
3583 dw2_asm_output_delta (4, landing_pad_lab
, function_start_lab
,
3586 dw2_asm_output_data (4, 0, "landing pad");
3588 dw2_asm_output_data_uleb128 (cs
->action
, "action");
3591 call_site_base
+= n
;
3595 sjlj_output_call_site_table ()
3597 int n
= cfun
->eh
->call_site_data_used
;
3600 for (i
= 0; i
< n
; ++i
)
3602 struct call_site_record
*cs
= &cfun
->eh
->call_site_data
[i
];
3604 dw2_asm_output_data_uleb128 (INTVAL (cs
->landing_pad
),
3605 "region %d landing pad", i
);
3606 dw2_asm_output_data_uleb128 (cs
->action
, "action");
3609 call_site_base
+= n
;
3613 output_function_exception_table ()
3615 int tt_format
, cs_format
, lp_format
, i
, n
;
3616 #ifdef HAVE_AS_LEB128
3617 char ttype_label
[32];
3618 char cs_after_size_label
[32];
3619 char cs_end_label
[32];
3625 int tt_format_size
= 0;
3627 /* Not all functions need anything. */
3628 if (! cfun
->uses_eh_lsda
)
3631 funcdef_number
= (USING_SJLJ_EXCEPTIONS
3632 ? sjlj_funcdef_number
3633 : current_funcdef_number
);
3635 #ifdef IA64_UNWIND_INFO
3636 fputs ("\t.personality\t", asm_out_file
);
3637 output_addr_const (asm_out_file
, eh_personality_libfunc
);
3638 fputs ("\n\t.handlerdata\n", asm_out_file
);
3639 /* Note that varasm still thinks we're in the function's code section.
3640 The ".endp" directive that will immediately follow will take us back. */
3642 (*targetm
.asm_out
.exception_section
) ();
3645 have_tt_data
= (VARRAY_ACTIVE_SIZE (cfun
->eh
->ttype_data
) > 0
3646 || VARRAY_ACTIVE_SIZE (cfun
->eh
->ehspec_data
) > 0);
3648 /* Indicate the format of the @TType entries. */
3650 tt_format
= DW_EH_PE_omit
;
3653 tt_format
= ASM_PREFERRED_EH_DATA_FORMAT (/*code=*/0, /*global=*/1);
3654 #ifdef HAVE_AS_LEB128
3655 ASM_GENERATE_INTERNAL_LABEL (ttype_label
, "LLSDATT", funcdef_number
);
3657 tt_format_size
= size_of_encoded_value (tt_format
);
3659 assemble_align (tt_format_size
* BITS_PER_UNIT
);
3662 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file
, "LLSDA", funcdef_number
);
3664 /* The LSDA header. */
3666 /* Indicate the format of the landing pad start pointer. An omitted
3667 field implies @LPStart == @Start. */
3668 /* Currently we always put @LPStart == @Start. This field would
3669 be most useful in moving the landing pads completely out of
3670 line to another section, but it could also be used to minimize
3671 the size of uleb128 landing pad offsets. */
3672 lp_format
= DW_EH_PE_omit
;
3673 dw2_asm_output_data (1, lp_format
, "@LPStart format (%s)",
3674 eh_data_format_name (lp_format
));
3676 /* @LPStart pointer would go here. */
3678 dw2_asm_output_data (1, tt_format
, "@TType format (%s)",
3679 eh_data_format_name (tt_format
));
3681 #ifndef HAVE_AS_LEB128
3682 if (USING_SJLJ_EXCEPTIONS
)
3683 call_site_len
= sjlj_size_of_call_site_table ();
3685 call_site_len
= dw2_size_of_call_site_table ();
3688 /* A pc-relative 4-byte displacement to the @TType data. */
3691 #ifdef HAVE_AS_LEB128
3692 char ttype_after_disp_label
[32];
3693 ASM_GENERATE_INTERNAL_LABEL (ttype_after_disp_label
, "LLSDATTD",
3695 dw2_asm_output_delta_uleb128 (ttype_label
, ttype_after_disp_label
,
3696 "@TType base offset");
3697 ASM_OUTPUT_LABEL (asm_out_file
, ttype_after_disp_label
);
3699 /* Ug. Alignment queers things. */
3700 unsigned int before_disp
, after_disp
, last_disp
, disp
;
3702 before_disp
= 1 + 1;
3703 after_disp
= (1 + size_of_uleb128 (call_site_len
)
3705 + VARRAY_ACTIVE_SIZE (cfun
->eh
->action_record_data
)
3706 + (VARRAY_ACTIVE_SIZE (cfun
->eh
->ttype_data
)
3712 unsigned int disp_size
, pad
;
3715 disp_size
= size_of_uleb128 (disp
);
3716 pad
= before_disp
+ disp_size
+ after_disp
;
3717 if (pad
% tt_format_size
)
3718 pad
= tt_format_size
- (pad
% tt_format_size
);
3721 disp
= after_disp
+ pad
;
3723 while (disp
!= last_disp
);
3725 dw2_asm_output_data_uleb128 (disp
, "@TType base offset");
3729 /* Indicate the format of the call-site offsets. */
3730 #ifdef HAVE_AS_LEB128
3731 cs_format
= DW_EH_PE_uleb128
;
3733 cs_format
= DW_EH_PE_udata4
;
3735 dw2_asm_output_data (1, cs_format
, "call-site format (%s)",
3736 eh_data_format_name (cs_format
));
3738 #ifdef HAVE_AS_LEB128
3739 ASM_GENERATE_INTERNAL_LABEL (cs_after_size_label
, "LLSDACSB",
3741 ASM_GENERATE_INTERNAL_LABEL (cs_end_label
, "LLSDACSE",
3743 dw2_asm_output_delta_uleb128 (cs_end_label
, cs_after_size_label
,
3744 "Call-site table length");
3745 ASM_OUTPUT_LABEL (asm_out_file
, cs_after_size_label
);
3746 if (USING_SJLJ_EXCEPTIONS
)
3747 sjlj_output_call_site_table ();
3749 dw2_output_call_site_table ();
3750 ASM_OUTPUT_LABEL (asm_out_file
, cs_end_label
);
3752 dw2_asm_output_data_uleb128 (call_site_len
,"Call-site table length");
3753 if (USING_SJLJ_EXCEPTIONS
)
3754 sjlj_output_call_site_table ();
3756 dw2_output_call_site_table ();
3759 /* ??? Decode and interpret the data for flag_debug_asm. */
3760 n
= VARRAY_ACTIVE_SIZE (cfun
->eh
->action_record_data
);
3761 for (i
= 0; i
< n
; ++i
)
3762 dw2_asm_output_data (1, VARRAY_UCHAR (cfun
->eh
->action_record_data
, i
),
3763 (i
? NULL
: "Action record table"));
3766 assemble_align (tt_format_size
* BITS_PER_UNIT
);
3768 i
= VARRAY_ACTIVE_SIZE (cfun
->eh
->ttype_data
);
3771 tree type
= VARRAY_TREE (cfun
->eh
->ttype_data
, i
);
3774 if (type
== NULL_TREE
)
3775 type
= integer_zero_node
;
3777 type
= lookup_type_for_runtime (type
);
3779 value
= expand_expr (type
, NULL_RTX
, VOIDmode
, EXPAND_INITIALIZER
);
3780 if (tt_format
== DW_EH_PE_absptr
|| tt_format
== DW_EH_PE_aligned
)
3781 assemble_integer (value
, tt_format_size
,
3782 tt_format_size
* BITS_PER_UNIT
, 1);
3784 dw2_asm_output_encoded_addr_rtx (tt_format
, value
, NULL
);
3787 #ifdef HAVE_AS_LEB128
3789 ASM_OUTPUT_LABEL (asm_out_file
, ttype_label
);
3792 /* ??? Decode and interpret the data for flag_debug_asm. */
3793 n
= VARRAY_ACTIVE_SIZE (cfun
->eh
->ehspec_data
);
3794 for (i
= 0; i
< n
; ++i
)
3795 dw2_asm_output_data (1, VARRAY_UCHAR (cfun
->eh
->ehspec_data
, i
),
3796 (i
? NULL
: "Exception specification table"));
3798 function_section (current_function_decl
);
3800 if (USING_SJLJ_EXCEPTIONS
)
3801 sjlj_funcdef_number
+= 1;