/* Implements exception handling.
- Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001 Free Software Foundation, Inc.
+ Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
+ 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
Contributed by Mike Stump <mrs@cygnus.com>.
This file is part of GCC.
#include "ggc.h"
#include "tm_p.h"
#include "target.h"
+#include "langhooks.h"
/* Provide defaults for stuff that may not be defined when using
sjlj exceptions. */
/* Map a type to a runtime object to match type. */
tree (*lang_eh_runtime_type) PARAMS ((tree));
-/* A list of labels used for exception handlers. */
-rtx exception_handler_labels;
+/* A hash table of label to region number. */
+
+struct ehl_map_entry
+{
+ rtx label;
+ struct eh_region *region;
+};
+
+static htab_t exception_handler_label_map;
static int call_site_base;
static unsigned int sjlj_funcdef_number;
/* An identifier for this region. */
int region_number;
+ /* When a region is deleted, its parents inherit the REG_EH_REGION
+ numbers already assigned. */
+ bitmap aka;
+
/* Each region does exactly one thing. */
enum eh_region_type
{
- ERT_CLEANUP = 1,
+ ERT_UNKNOWN = 0,
+ ERT_CLEANUP,
ERT_TRY,
ERT_CATCH,
ERT_ALLOWED_EXCEPTIONS,
rtx continue_label;
} try;
- /* The list through the catch handlers, the type object
- matched, and a pointer to the generated code. */
+ /* The list through the catch handlers, the list of type objects
+ matched, and the list of associated filters. */
struct {
struct eh_region *next_catch;
struct eh_region *prev_catch;
- tree type;
- int filter;
+ tree type_list;
+ tree filter_list;
} catch;
/* A tree_list of allowed types. */
int filter;
} allowed;
- /* The type given by a call to "throw foo();", or discovered
+ /* The type given by a call to "throw foo();", or discovered
for a throw. */
struct {
tree type;
/* This is the region for which we are processing catch blocks. */
struct eh_region *try_region;
- /* A stack (TREE_LIST) of lists of handlers. The TREE_VALUE of each
- node is itself a TREE_CHAINed list of handlers for regions that
- are not yet closed. The TREE_VALUE of each entry contains the
- handler for the corresponding entry on the ehstack. */
- tree protect_list;
-
rtx filter;
rtx exc_ptr;
\f
static void mark_eh_region PARAMS ((struct eh_region *));
+static int mark_ehl_map_entry PARAMS ((PTR *, PTR));
+static void mark_ehl_map PARAMS ((void *));
+
+static void free_region PARAMS ((struct eh_region *));
static int t2r_eq PARAMS ((const PTR,
const PTR));
static void collect_eh_region_array PARAMS ((void));
static void resolve_fixup_regions PARAMS ((void));
static void remove_fixup_regions PARAMS ((void));
+static void remove_unreachable_regions PARAMS ((rtx));
static void convert_from_eh_region_ranges_1 PARAMS ((rtx *, int *, int));
static struct eh_region *duplicate_eh_region_1 PARAMS ((struct eh_region *,
PARAMS ((rtx, struct sjlj_lp_info *));
static void sjlj_build_landing_pads PARAMS ((void));
+static hashval_t ehl_hash PARAMS ((const PTR));
+static int ehl_eq PARAMS ((const PTR,
+ const PTR));
+static void ehl_free PARAMS ((PTR));
+static void add_ehl_entry PARAMS ((rtx,
+ struct eh_region *));
static void remove_exception_handler_label PARAMS ((rtx));
static void remove_eh_handler PARAMS ((struct eh_region *));
+static int for_each_eh_label_1 PARAMS ((PTR *, PTR));
struct reachable_info;
\f
/* Routine to see if exception handling is turned on.
DO_WARN is non-zero if we want to inform the user that exception
- handling is turned off.
+ handling is turned off.
This is used to ensure that -fexceptions has been specified if the
compiler tries to use any exception-specific functions. */
void
init_eh ()
{
- ggc_add_rtx_root (&exception_handler_labels, 1);
+ ggc_add_root (&exception_handler_label_map, 1, 1, mark_ehl_map);
if (! flag_exceptions)
return;
{
tree f_jbuf, f_per, f_lsda, f_prev, f_cs, f_data, tmp;
- sjlj_fc_type_node = make_lang_type (RECORD_TYPE);
+ sjlj_fc_type_node = (*lang_hooks.types.make_type) (RECORD_TYPE);
ggc_add_tree_root (&sjlj_fc_type_node, 1);
f_prev = build_decl (FIELD_DECL, get_identifier ("__prev"),
DECL_FIELD_CONTEXT (f_cs) = sjlj_fc_type_node;
tmp = build_index_type (build_int_2 (4 - 1, 0));
- tmp = build_array_type (type_for_mode (word_mode, 1), tmp);
+ tmp = build_array_type ((*lang_hooks.types.type_for_mode) (word_mode, 1),
+ tmp);
f_data = build_decl (FIELD_DECL, get_identifier ("__data"), tmp);
DECL_FIELD_CONTEXT (f_data) = sjlj_fc_type_node;
switch (region->type)
{
+ case ERT_UNKNOWN:
+ /* This can happen if a nested function is inside the body of a region
+ and we do a GC as part of processing it. */
+ break;
case ERT_CLEANUP:
ggc_mark_tree (region->u.cleanup.exp);
break;
ggc_mark_rtx (region->u.try.continue_label);
break;
case ERT_CATCH:
- ggc_mark_tree (region->u.catch.type);
+ ggc_mark_tree (region->u.catch.type_list);
+ ggc_mark_tree (region->u.catch.filter_list);
break;
case ERT_ALLOWED_EXCEPTIONS:
ggc_mark_tree (region->u.allowed.type_list);
ggc_mark_rtx (region->post_landing_pad);
}
+static int
+mark_ehl_map_entry (pentry, data)
+ PTR *pentry;
+ PTR data ATTRIBUTE_UNUSED;
+{
+ struct ehl_map_entry *entry = *(struct ehl_map_entry **) pentry;
+ ggc_mark_rtx (entry->label);
+ return 1;
+}
+
+static void
+mark_ehl_map (pp)
+ void *pp;
+{
+ htab_t map = *(htab_t *) pp;
+ if (map)
+ htab_traverse (map, mark_ehl_map_entry, NULL);
+}
+
void
mark_eh_status (eh)
struct eh_status *eh;
tree_done:;
}
- ggc_mark_tree (eh->protect_list);
ggc_mark_rtx (eh->filter);
ggc_mark_rtx (eh->exc_ptr);
ggc_mark_tree_varray (eh->ttype_data);
ggc_mark_rtx (eh->sjlj_exit_after);
}
+static inline void
+free_region (r)
+ struct eh_region *r;
+{
+ /* Note that the aka bitmap is freed by regset_release_memory. But if
+ we ever replace with a non-obstack implementation, this would be
+ the place to do it. */
+ free (r);
+}
+
void
free_eh_status (f)
struct function *f;
struct eh_region *r = eh->region_array[i];
/* Mind we don't free a region struct more than once. */
if (r && r->region_number == i)
- free (r);
+ free_region (r);
}
free (eh->region_array);
}
else if (r->next_peer)
{
next = r->next_peer;
- free (r);
+ free_region (r);
r = next;
}
else
{
do {
next = r->outer;
- free (r);
+ free_region (r);
r = next;
if (r == NULL)
goto tree_done;
} while (r->next_peer == NULL);
next = r->next_peer;
- free (r);
+ free_region (r);
r = next;
}
}
free (eh);
f->eh = NULL;
+
+ if (exception_handler_label_map)
+ {
+ htab_delete (exception_handler_label_map);
+ exception_handler_label_map = NULL;
+ }
}
\f
struct eh_region *cur_region = cfun->eh->cur_region;
rtx note;
- /* Create a nute marking the end of this region. */
+ /* Create a note marking the end of this region. */
note = emit_note (NULL, NOTE_INSN_EH_REGION_END);
NOTE_EH_HANDLER (note) = cur_region->region_number;
emit_label (region->label);
/* Give the language a chance to specify an action to be taken if an
- exception is thrown that would propogate out of the HANDLER. */
- protect_cleanup_actions
- = (lang_protect_cleanup_actions
- ? (*lang_protect_cleanup_actions) ()
+ exception is thrown that would propagate out of the HANDLER. */
+ protect_cleanup_actions
+ = (lang_protect_cleanup_actions
+ ? (*lang_protect_cleanup_actions) ()
: NULL_TREE);
if (protect_cleanup_actions)
emit_jump (region->u.try.continue_label);
}
-/* Begin a catch clause. TYPE is the type caught, or null if this is
- a catch-all clause. */
+/* Begin a catch clause. TYPE is the type caught, a list of such types, or
+ null if this is a catch-all clause. Providing a type list enables to
+ associate the catch region with potentially several exception types, which
+ is useful e.g. for Ada. */
void
-expand_start_catch (type)
- tree type;
+expand_start_catch (type_or_list)
+ tree type_or_list;
{
struct eh_region *t, *c, *l;
+ tree type_list;
if (! doing_eh (0))
return;
- if (type)
- add_type_for_runtime (type);
+ type_list = type_or_list;
+
+ if (type_or_list)
+ {
+ /* Ensure to always end up with a type list to normalize further
+ processing, then register each type against the runtime types
+ map. */
+ tree type_node;
+
+ if (TREE_CODE (type_or_list) != TREE_LIST)
+ type_list = tree_cons (NULL_TREE, type_or_list, NULL_TREE);
+
+ type_node = type_list;
+ for (; type_node; type_node = TREE_CHAIN (type_node))
+ add_type_for_runtime (TREE_VALUE (type_node));
+ }
+
expand_eh_region_start ();
t = cfun->eh->try_region;
c = cfun->eh->cur_region;
c->type = ERT_CATCH;
- c->u.catch.type = type;
+ c->u.catch.type_list = type_list;
c->label = gen_label_rtx ();
l = t->u.try.last_catch;
return filter;
}
\f
-/* Begin a region that will contain entries created with
- add_partial_entry. */
-
-void
-begin_protect_partials ()
-{
- /* Push room for a new list. */
- cfun->eh->protect_list
- = tree_cons (NULL_TREE, NULL_TREE, cfun->eh->protect_list);
-}
-
-/* Start a new exception region for a region of code that has a
- cleanup action and push the HANDLER for the region onto
- protect_list. All of the regions created with add_partial_entry
- will be ended when end_protect_partials is invoked. */
-
-void
-add_partial_entry (handler)
- tree handler;
-{
- expand_eh_region_start ();
-
- /* ??? This comment was old before the most recent rewrite. We
- really ought to fix the callers at some point. */
- /* For backwards compatibility, we allow callers to omit calls to
- begin_protect_partials for the outermost region. So, we must
- explicitly do so here. */
- if (!cfun->eh->protect_list)
- begin_protect_partials ();
-
- /* Add this entry to the front of the list. */
- TREE_VALUE (cfun->eh->protect_list)
- = tree_cons (NULL_TREE, handler, TREE_VALUE (cfun->eh->protect_list));
-}
-
-/* End all the pending exception regions on protect_list. */
-
-void
-end_protect_partials ()
-{
- tree t;
-
- /* ??? This comment was old before the most recent rewrite. We
- really ought to fix the callers at some point. */
- /* For backwards compatibility, we allow callers to omit the call to
- begin_protect_partials for the outermost region. So,
- PROTECT_LIST may be NULL. */
- if (!cfun->eh->protect_list)
- return;
-
- /* Pop the topmost entry. */
- t = TREE_VALUE (cfun->eh->protect_list);
- cfun->eh->protect_list = TREE_CHAIN (cfun->eh->protect_list);
-
- /* End all the exception regions. */
- for (; t; t = TREE_CHAIN (t))
- expand_eh_region_end_cleanup (TREE_VALUE (t));
-}
-
-\f
/* This section is for the exception handling specific optimization pass. */
/* Random access the exception region tree. It's just as simple to
}
}
+/* Remove all regions whose labels are not reachable from insns. */
+
+static void
+remove_unreachable_regions (insns)
+ rtx insns;
+{
+ int i, *uid_region_num;
+ bool *reachable;
+ struct eh_region *r;
+ rtx insn;
+
+ uid_region_num = xcalloc (get_max_uid (), sizeof(int));
+ reachable = xcalloc (cfun->eh->last_region_number + 1, sizeof(bool));
+
+ for (i = cfun->eh->last_region_number; i > 0; --i)
+ {
+ r = cfun->eh->region_array[i];
+ if (!r || r->region_number != i)
+ continue;
+
+ if (r->resume)
+ {
+ if (uid_region_num[INSN_UID (r->resume)])
+ abort ();
+ uid_region_num[INSN_UID (r->resume)] = i;
+ }
+ if (r->label)
+ {
+ if (uid_region_num[INSN_UID (r->label)])
+ abort ();
+ uid_region_num[INSN_UID (r->label)] = i;
+ }
+ if (r->type == ERT_TRY && r->u.try.continue_label)
+ {
+ if (uid_region_num[INSN_UID (r->u.try.continue_label)])
+ abort ();
+ uid_region_num[INSN_UID (r->u.try.continue_label)] = i;
+ }
+ }
+
+ for (insn = insns; insn; insn = NEXT_INSN (insn))
+ reachable[uid_region_num[INSN_UID (insn)]] = true;
+
+ for (i = cfun->eh->last_region_number; i > 0; --i)
+ {
+ r = cfun->eh->region_array[i];
+ if (r && r->region_number == i && !reachable[i])
+ {
+ /* Don't remove ERT_THROW regions if their outer region
+ is reachable. */
+ if (r->type == ERT_THROW
+ && r->outer
+ && reachable[r->outer->region_number])
+ continue;
+
+ remove_eh_handler (r);
+ }
+ }
+
+ free (reachable);
+ free (uid_region_num);
+}
+
/* Turn NOTE_INSN_EH_REGION notes into REG_EH_REGION notes for each
can_throw instruction in the region. */
free (stack);
remove_fixup_regions ();
+ remove_unreachable_regions (insns);
+}
+
+static void
+add_ehl_entry (label, region)
+ rtx label;
+ struct eh_region *region;
+{
+ struct ehl_map_entry **slot, *entry;
+
+ LABEL_PRESERVE_P (label) = 1;
+
+ entry = (struct ehl_map_entry *) xmalloc (sizeof (*entry));
+ entry->label = label;
+ entry->region = region;
+
+ slot = (struct ehl_map_entry **)
+ htab_find_slot (exception_handler_label_map, entry, INSERT);
+
+ /* Before landing pad creation, each exception handler has its own
+ label. After landing pad creation, the exception handlers may
+ share landing pads. This is ok, since maybe_remove_eh_handler
+ only requires the 1-1 mapping before landing pad creation. */
+ if (*slot && !cfun->eh->built_landing_pads)
+ abort ();
+
+ *slot = entry;
+}
+
+static void
+ehl_free (pentry)
+ PTR pentry;
+{
+ struct ehl_map_entry *entry = (struct ehl_map_entry *)pentry;
+ LABEL_PRESERVE_P (entry->label) = 0;
+ free (entry);
}
void
find_exception_handler_labels ()
{
- rtx list = NULL_RTX;
int i;
- free_EXPR_LIST_list (&exception_handler_labels);
+ if (exception_handler_label_map)
+ htab_empty (exception_handler_label_map);
+ else
+ {
+ /* ??? The expansion factor here (3/2) must be greater than the htab
+ occupancy factor (4/3) to avoid unnecessary resizing. */
+ exception_handler_label_map
+ = htab_create (cfun->eh->last_region_number * 3 / 2,
+ ehl_hash, ehl_eq, ehl_free);
+ }
if (cfun->eh->region_tree == NULL)
return;
struct eh_region *region = cfun->eh->region_array[i];
rtx lab;
- if (! region)
+ if (! region || region->region_number != i)
continue;
if (cfun->eh->built_landing_pads)
lab = region->landing_pad;
lab = region->label;
if (lab)
- list = alloc_EXPR_LIST (0, lab, list);
+ add_ehl_entry (lab, region);
}
/* For sjlj exceptions, need the return label to remain live until
after landing pad generation. */
if (USING_SJLJ_EXCEPTIONS && ! cfun->eh->built_landing_pads)
- list = alloc_EXPR_LIST (0, return_label, list);
-
- exception_handler_labels = list;
+ add_ehl_entry (return_label, NULL);
}
+bool
+current_function_has_exception_handlers ()
+{
+ int i;
+
+ for (i = cfun->eh->last_region_number; i > 0; --i)
+ {
+ struct eh_region *region = cfun->eh->region_array[i];
+
+ if (! region || region->region_number != i)
+ continue;
+ if (region->type != ERT_THROW)
+ return true;
+ }
+
+ return false;
+}
\f
static struct eh_region *
duplicate_eh_region_1 (o, map)
break;
case ERT_CATCH:
- n->u.catch.type = o->u.catch.type;
+ n->u.catch.type_list = o->u.catch.type_list;
break;
case ERT_ALLOWED_EXCEPTIONS:
case ERT_THROW:
n->u.throw.type = o->u.throw.type;
-
+
default:
abort ();
}
n->inner = n_array[o->inner->region_number];
if (o->next_peer)
n->next_peer = n_array[o->next_peer->region_number];
-}
+}
int
duplicate_eh_regions (ifun, map)
*slot = tree_cons (type, runtime, NULL_TREE);
}
}
-
+
static tree
lookup_type_for_runtime (type)
tree type;
slot = (tree *) htab_find_slot_with_hash (type_to_runtime_map, type,
TYPE_HASH (type), NO_INSERT);
- /* We should have always inserrted the data earlier. */
+ /* We should have always inserted the data earlier. */
return TREE_VALUE (*slot);
}
/* Look up each type in the list and encode its filter
value as a uleb128. Terminate the list with 0. */
for (; list ; list = TREE_CHAIN (list))
- push_uleb128 (&cfun->eh->ehspec_data,
+ push_uleb128 (&cfun->eh->ehspec_data,
add_ttypes_entry (ttypes_hash, TREE_VALUE (list)));
VARRAY_PUSH_UCHAR (cfun->eh->ehspec_data, 0);
}
switch (r->type)
{
case ERT_CATCH:
- r->u.catch.filter = add_ttypes_entry (ttypes, r->u.catch.type);
+ /* Whatever type_list is (NULL or true list), we build a list
+ of filters for the region. */
+ r->u.catch.filter_list = NULL_TREE;
+
+ if (r->u.catch.type_list != NULL)
+ {
+ /* Get a filter value for each of the types caught and store
+ them in the region's dedicated list. */
+ tree tp_node = r->u.catch.type_list;
+
+ for (;tp_node; tp_node = TREE_CHAIN (tp_node))
+ {
+ int flt = add_ttypes_entry (ttypes, TREE_VALUE (tp_node));
+ tree flt_node = build_int_2 (flt, 0);
+
+ r->u.catch.filter_list
+ = tree_cons (NULL_TREE, flt_node, r->u.catch.filter_list);
+ }
+ }
+ else
+ {
+ /* Get a filter value for the NULL list also since it will need
+ an action record anyway. */
+ int flt = add_ttypes_entry (ttypes, NULL);
+ tree flt_node = build_int_2 (flt, 0);
+
+ r->u.catch.filter_list
+ = tree_cons (NULL_TREE, flt_node, r->u.catch.filter_list);
+ }
+
break;
case ERT_ALLOWED_EXCEPTIONS:
all the way up the chain until blocked by a cleanup. */
/* ??? Outer try regions can share landing pads with inner
try regions if the types are completely non-overlapping,
- and there are no interveaning cleanups. */
+ and there are no intervening cleanups. */
region->post_landing_pad = gen_label_rtx ();
for (c = region->u.try.catch; c ; c = c->u.catch.next_catch)
{
/* ??? _Unwind_ForcedUnwind wants no match here. */
- if (c->u.catch.type == NULL)
+ if (c->u.catch.type_list == NULL)
emit_jump (c->label);
else
- emit_cmp_and_jump_insns (cfun->eh->filter,
- GEN_INT (c->u.catch.filter),
- EQ, NULL_RTX, word_mode, 0,
- c->label);
+ {
+ /* Need for one cmp/jump per type caught. Each type
+ list entry has a matching entry in the filter list
+ (see assign_filter_values). */
+ tree tp_node = c->u.catch.type_list;
+ tree flt_node = c->u.catch.filter_list;
+
+ for (; tp_node; )
+ {
+ emit_cmp_and_jump_insns
+ (cfun->eh->filter,
+ GEN_INT (tree_low_cst (TREE_VALUE (flt_node), 0)),
+ EQ, NULL_RTX, word_mode, 0, c->label);
+
+ tp_node = TREE_CHAIN (tp_node);
+ flt_node = TREE_CHAIN (flt_node);
+ }
+ }
}
}
for (insn = get_insns (); insn ; insn = NEXT_INSN (insn))
{
struct eh_region *region;
+ enum reachable_code rc;
tree type_thrown;
rtx note;
/* Find the first containing region that might handle the exception.
That's the landing pad to which we will transfer control. */
+ rc = RNL_NOT_CAUGHT;
for (; region; region = region->outer)
- if (reachable_next_level (region, type_thrown, 0) != RNL_NOT_CAUGHT)
- break;
-
- if (region)
+ {
+ rc = reachable_next_level (region, type_thrown, 0);
+ if (rc != RNL_NOT_CAUGHT)
+ break;
+ }
+ if (rc == RNL_MAYBE_CAUGHT || rc == RNL_CAUGHT)
{
lp_info[region->region_number].directly_reachable = 1;
found_one = true;
index = 0;
for (i = cfun->eh->last_region_number; i > 0; --i)
- if (lp_info[i].directly_reachable
- && lp_info[i].action_index >= 0)
+ if (lp_info[i].directly_reachable)
lp_info[i].dispatch_index = index++;
/* Finally: assign call-site values. If dwarf2 terms, this would be
}
else
emit_move_insn (mem, const0_rtx);
-
+
#ifdef DONT_USE_BUILTIN_SETJMP
{
rtx x, note;
start_sequence ();
emit_label (dispatch_label);
-
+
#ifndef DONT_USE_BUILTIN_SETJMP
expand_builtin_setjmp_receiver (dispatch_label);
#endif
first_reachable = 0;
for (i = cfun->eh->last_region_number; i > 0; --i)
{
- if (! lp_info[i].directly_reachable
- || lp_info[i].action_index < 0)
+ if (! lp_info[i].directly_reachable)
continue;
if (! first_reachable)
cleanup_cfg (CLEANUP_PRE_LOOP);
}
\f
+static hashval_t
+ehl_hash (pentry)
+ const PTR pentry;
+{
+ struct ehl_map_entry *entry = (struct ehl_map_entry *) pentry;
+
+ /* 2^32 * ((sqrt(5) - 1) / 2) */
+ const hashval_t scaled_golden_ratio = 0x9e3779b9;
+ return CODE_LABEL_NUMBER (entry->label) * scaled_golden_ratio;
+}
+
+static int
+ehl_eq (pentry, pdata)
+ const PTR pentry;
+ const PTR pdata;
+{
+ struct ehl_map_entry *entry = (struct ehl_map_entry *) pentry;
+ struct ehl_map_entry *data = (struct ehl_map_entry *) pdata;
+
+ return entry->label == data->label;
+}
+
/* This section handles removing dead code for flow. */
-/* Remove LABEL from the exception_handler_labels list. */
+/* Remove LABEL from exception_handler_label_map. */
static void
remove_exception_handler_label (label)
rtx label;
{
- rtx *pl, l;
+ struct ehl_map_entry **slot, tmp;
- for (pl = &exception_handler_labels, l = *pl;
- XEXP (l, 0) != label;
- pl = &XEXP (l, 1), l = *pl)
- continue;
+ /* If exception_handler_label_map was not built yet,
+ there is nothing to do. */
+ if (exception_handler_label_map == NULL)
+ return;
- *pl = XEXP (l, 1);
- free_EXPR_LIST_node (l);
+ tmp.label = label;
+ slot = (struct ehl_map_entry **)
+ htab_find_slot (exception_handler_label_map, &tmp, NO_INSERT);
+ if (! slot)
+ abort ();
+
+ htab_clear_slot (exception_handler_label_map, (void **) slot);
}
/* Splice REGION from the region tree etc. */
remove_eh_handler (region)
struct eh_region *region;
{
- struct eh_region **pp, *p;
+ struct eh_region **pp, **pp_start, *p, *outer, *inner;
rtx lab;
- int i;
/* For the benefit of efficiently handling REG_EH_REGION notes,
replace this region in the region array with its containing
region. Note that previous region deletions may result in
- multiple copies of this region in the array, so we have to
- search the whole thing. */
- for (i = cfun->eh->last_region_number; i > 0; --i)
- if (cfun->eh->region_array[i] == region)
- cfun->eh->region_array[i] = region->outer;
+ multiple copies of this region in the array, so we have a
+ list of alternate numbers by which we are known. */
+
+ outer = region->outer;
+ cfun->eh->region_array[region->region_number] = outer;
+ if (region->aka)
+ {
+ int i;
+ EXECUTE_IF_SET_IN_BITMAP (region->aka, 0, i,
+ { cfun->eh->region_array[i] = outer; });
+ }
+
+ if (outer)
+ {
+ if (!outer->aka)
+ outer->aka = BITMAP_XMALLOC ();
+ if (region->aka)
+ bitmap_a_or_b (outer->aka, outer->aka, region->aka);
+ bitmap_set_bit (outer->aka, region->region_number);
+ }
if (cfun->eh->built_landing_pads)
lab = region->landing_pad;
if (lab)
remove_exception_handler_label (lab);
- if (region->outer)
- pp = ®ion->outer->inner;
+ if (outer)
+ pp_start = &outer->inner;
else
- pp = &cfun->eh->region_tree;
- for (p = *pp; p != region; pp = &p->next_peer, p = *pp)
+ pp_start = &cfun->eh->region_tree;
+ for (pp = pp_start, p = *pp; p != region; pp = &p->next_peer, p = *pp)
continue;
+ *pp = region->next_peer;
- if (region->inner)
+ inner = region->inner;
+ if (inner)
{
- for (p = region->inner; p->next_peer ; p = p->next_peer)
- p->outer = region->outer;
- p->next_peer = region->next_peer;
- p->outer = region->outer;
- *pp = region->inner;
+ for (p = inner; p->next_peer ; p = p->next_peer)
+ p->outer = outer;
+ p->outer = outer;
+
+ p->next_peer = *pp_start;
+ *pp_start = inner;
}
- else
- *pp = region->next_peer;
if (region->type == ERT_CATCH)
{
}
}
- free (region);
+ free_region (region);
}
/* LABEL heads a basic block that is about to be deleted. If this
maybe_remove_eh_handler (label)
rtx label;
{
- int i;
+ struct ehl_map_entry **slot, tmp;
+ struct eh_region *region;
/* ??? After generating landing pads, it's not so simple to determine
if the region data is completely unused. One must examine the
if (cfun->eh->built_landing_pads)
return;
- for (i = cfun->eh->last_region_number; i > 0; --i)
+ tmp.label = label;
+ slot = (struct ehl_map_entry **)
+ htab_find_slot (exception_handler_label_map, &tmp, NO_INSERT);
+ if (! slot)
+ return;
+ region = (*slot)->region;
+ if (! region)
+ return;
+
+ /* Flow will want to remove MUST_NOT_THROW regions as unreachable
+ because there is no path to the fallback call to terminate.
+ But the region continues to affect call-site data until there
+ are no more contained calls, which we don't see here. */
+ if (region->type == ERT_MUST_NOT_THROW)
{
- struct eh_region *region = cfun->eh->region_array[i];
- if (region && region->label == label)
- {
- /* Flow will want to remove MUST_NOT_THROW regions as unreachable
- because there is no path to the fallback call to terminate.
- But the region continues to affect call-site data until there
- are no more contained calls, which we don't see here. */
- if (region->type == ERT_MUST_NOT_THROW)
- {
- remove_exception_handler_label (region->label);
- region->label = NULL_RTX;
- }
- else
- remove_eh_handler (region);
- break;
- }
+ htab_clear_slot (exception_handler_label_map, (void **) slot);
+ region->label = NULL_RTX;
}
+ else
+ remove_eh_handler (region);
}
+/* Invokes CALLBACK for every exception handler label. Only used by old
+ loop hackery; should not be used by new code. */
+
+void
+for_each_eh_label (callback)
+ void (*callback) PARAMS ((rtx));
+{
+ htab_traverse (exception_handler_label_map, for_each_eh_label_1,
+ (void *)callback);
+}
+
+static int
+for_each_eh_label_1 (pentry, data)
+ PTR *pentry;
+ PTR data;
+{
+ struct ehl_map_entry *entry = *(struct ehl_map_entry **)pentry;
+ void (*callback) PARAMS ((rtx)) = (void (*) PARAMS ((rtx))) data;
+
+ (*callback) (entry->label);
+ return 1;
+}
\f
/* This section describes CFG exception edges for flow. */
/* A subroutine of reachable_next_level. If we are collecting a list
of handlers, add one. After landing pad generation, reference
it instead of the handlers themselves. Further, the handlers are
- all wired together, so by referencing one, we've got them all.
+ all wired together, so by referencing one, we've got them all.
Before landing pad generation we reference each handler individually.
LP_REGION contains the landing pad; REGION is the handler. */
info->handlers = alloc_INSN_LIST (region->label, info->handlers);
}
-/* Process one level of exception regions for reachability.
+/* Process one level of exception regions for reachability.
If TYPE_THROWN is non-null, then it is the *exact* type being
propagated. If INFO is non-null, then collect handler labels
and caught/allowed type information between invocations. */
/* A catch-all handler ends the search. */
/* ??? _Unwind_ForcedUnwind will want outer cleanups
to be run as well. */
- if (c->u.catch.type == NULL)
+ if (c->u.catch.type_list == NULL)
{
add_reachable_handler (info, region, c);
return RNL_CAUGHT;
if (type_thrown)
{
- /* If we have a type match, end the search. */
- if (c->u.catch.type == type_thrown
- || (lang_eh_type_covers
- && (*lang_eh_type_covers) (c->u.catch.type,
- type_thrown)))
+ /* If we have at least one type match, end the search. */
+ tree tp_node = c->u.catch.type_list;
+
+ for (; tp_node; tp_node = TREE_CHAIN (tp_node))
{
- add_reachable_handler (info, region, c);
- return RNL_CAUGHT;
+ tree type = TREE_VALUE (tp_node);
+
+ if (type == type_thrown
+ || (lang_eh_type_covers
+ && (*lang_eh_type_covers) (type, type_thrown)))
+ {
+ add_reachable_handler (info, region, c);
+ return RNL_CAUGHT;
+ }
}
/* If we have definitive information of a match failure,
return RNL_NOT_CAUGHT;
}
+ /* At this point, we either don't know what type is thrown or
+ don't have front-end assistance to help deciding if it is
+ covered by one of the types in the list for this region.
+
+ We'd then like to add this region to the list of reachable
+ handlers since it is indeed potentially reachable based on the
+ information we have.
+
+ Actually, this handler is for sure not reachable if all the
+ types it matches have already been caught. That is, it is only
+ potentially reachable if at least one of the types it catches
+ has not been previously caught. */
+
if (! info)
ret = RNL_MAYBE_CAUGHT;
-
- /* A type must not have been previously caught. */
- else if (! check_handled (info->types_caught, c->u.catch.type))
+ else
{
- add_reachable_handler (info, region, c);
- info->types_caught = tree_cons (NULL, c->u.catch.type,
- info->types_caught);
+ tree tp_node = c->u.catch.type_list;
+ bool maybe_reachable = false;
- /* ??? If the catch type is a base class of every allowed
- type, then we know we can stop the search. */
- ret = RNL_MAYBE_CAUGHT;
+ /* Compute the potential reachability of this handler and
+ update the list of types caught at the same time. */
+ for (; tp_node; tp_node = TREE_CHAIN (tp_node))
+ {
+ tree type = TREE_VALUE (tp_node);
+
+ if (! check_handled (info->types_caught, type))
+ {
+ info->types_caught
+ = tree_cons (NULL, type, info->types_caught);
+
+ maybe_reachable = true;
+ }
+ }
+
+ if (maybe_reachable)
+ {
+ add_reachable_handler (info, region, c);
+
+ /* ??? If the catch type is a base class of every allowed
+ type, then we know we can stop the search. */
+ ret = RNL_MAYBE_CAUGHT;
+ }
}
}
info->types_allowed = tree_cons (NULL_TREE,
region->u.allowed.type_list,
info->types_allowed);
-
+
/* If we have definitive information about the type hierarchy,
then we can tell if the thrown type will pass through the
filter. */
case ERT_THROW:
case ERT_FIXUP:
+ case ERT_UNKNOWN:
/* Shouldn't see these here. */
break;
}
iwhich = DBX_REGISTER_NUMBER (iwhich);
#endif
- return GEN_INT (iwhich);
+ return GEN_INT (iwhich);
}
/* Given a value extracted from the return address register or stack slot,
/* First mask out any unwanted bits. */
#ifdef MASK_RETURN_ADDR
- expand_and (addr, MASK_RETURN_ADDR, addr);
+ expand_and (Pmode, addr, MASK_RETURN_ADDR, addr);
#endif
/* Then adjust to find the real return address. */
/* Process the associated catch regions in reverse order.
If there's a catch-all handler, then we don't need to
search outer regions. Use a magic -3 value to record
- that we havn't done the outer search. */
+ that we haven't done the outer search. */
next = -3;
for (c = region->u.try.last_catch; c ; c = c->u.catch.prev_catch)
{
- if (c->u.catch.type == NULL)
- next = add_action_record (ar_hash, c->u.catch.filter, 0);
+ if (c->u.catch.type_list == NULL)
+ {
+ /* Retrieve the filter from the head of the filter list
+ where we have stored it (see assign_filter_values). */
+ int filter
+ = TREE_INT_CST_LOW (TREE_VALUE (c->u.catch.filter_list));
+
+ next = add_action_record (ar_hash, filter, 0);
+ }
else
{
+ /* Once the outer search is done, trigger an action record for
+ each filter we have. */
+ tree flt_node;
+
if (next == -3)
{
next = collect_one_action_chain (ar_hash, region->outer);
else if (next <= 0)
next = add_action_record (ar_hash, 0, 0);
}
- next = add_action_record (ar_hash, c->u.catch.filter, next);
+
+ flt_node = c->u.catch.filter_list;
+ for (; flt_node; flt_node = TREE_CHAIN (flt_node))
+ {
+ int filter = TREE_INT_CST_LOW (TREE_VALUE (flt_node));
+ next = add_action_record (ar_hash, filter, next);
+ }
}
}
return next;
are created. */
if (this_action >= -1)
{
- call_site = add_call_site (this_landing_pad,
+ call_site = add_call_site (this_landing_pad,
this_action < 0 ? 0 : this_action);
note = emit_note_before (NOTE_INSN_EH_REGION_BEG, iter);
NOTE_EH_HANDLER (note) = call_site;
{
#ifdef HAVE_AS_LEB128
char ttype_after_disp_label[32];
- ASM_GENERATE_INTERNAL_LABEL (ttype_after_disp_label, "LLSDATTD",
+ ASM_GENERATE_INTERNAL_LABEL (ttype_after_disp_label, "LLSDATTD",
funcdef_number);
dw2_asm_output_delta_uleb128 (ttype_label, ttype_after_disp_label,
"@TType base offset");
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