static void sjlj_emit_dispatch_table (rtx, struct sjlj_lp_info *);
static void sjlj_build_landing_pads (void);
-static hashval_t ehl_hash (const void *);
-static int ehl_eq (const void *, const void *);
-static void add_ehl_entry (rtx, struct eh_region *);
-static void remove_exception_handler_label (rtx);
static void remove_eh_handler (struct eh_region *);
static void remove_eh_handler_and_replace (struct eh_region *,
struct eh_region *);
-static int for_each_eh_label_1 (void **, void *);
/* The return value of reachable_next_level. */
enum reachable_code
return cfun->eh->last_region_number + 1;
}
-/* Remove all regions whose labels are not reachable from insns. */
-
-static void
-rtl_remove_unreachable_regions (rtx insns)
-{
- int i, *uid_region_num;
- sbitmap reachable;
- struct eh_region *r;
- rtx insn;
-
- uid_region_num = XCNEWVEC (int, get_max_uid ());
- reachable = sbitmap_alloc (cfun->eh->last_region_number + 1);
- sbitmap_zero (reachable);
-
- for (i = cfun->eh->last_region_number; i > 0; --i)
- {
- r = VEC_index (eh_region, cfun->eh->region_array, i);
- if (!r || r->region_number != i)
- continue;
-
- if (r->resume)
- {
- gcc_assert (!uid_region_num[INSN_UID (r->resume)]);
- uid_region_num[INSN_UID (r->resume)] = i;
- }
- if (r->label)
- {
- gcc_assert (!uid_region_num[INSN_UID (r->label)]);
- uid_region_num[INSN_UID (r->label)] = i;
- }
- }
-
- for (insn = insns; insn; insn = NEXT_INSN (insn))
- SET_BIT (reachable, uid_region_num[INSN_UID (insn)]);
-
- remove_unreachable_regions (reachable, NULL);
-
- sbitmap_free (reachable);
- free (uid_region_num);
-}
-
/* Set up EH labels for RTL. */
void
convert_from_eh_region_ranges (void)
{
- rtx insns = get_insns ();
int i, n = cfun->eh->last_region_number;
/* Most of the work is already done at the tree level. All we need to
if (region && region->tree_label)
region->label = DECL_RTL_IF_SET (region->tree_label);
}
-
- rtl_remove_unreachable_regions (insns);
-}
-
-static void
-add_ehl_entry (rtx label, struct eh_region *region)
-{
- struct ehl_map_entry **slot, *entry;
-
- LABEL_PRESERVE_P (label) = 1;
-
- entry = GGC_NEW (struct ehl_map_entry);
- entry->label = label;
- entry->region = region;
-
- slot = (struct ehl_map_entry **)
- htab_find_slot (crtl->eh.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. */
- gcc_assert (!*slot || crtl->eh.built_landing_pads);
-
- *slot = entry;
}
void
{
int i;
- if (crtl->eh.exception_handler_label_map)
- htab_empty (crtl->eh.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. */
- crtl->eh.exception_handler_label_map
- = htab_create_ggc (cfun->eh->last_region_number * 3 / 2,
- ehl_hash, ehl_eq, NULL);
- }
-
if (cfun->eh->region_tree == NULL)
return;
lab = region->landing_pad;
else
lab = region->label;
-
- if (lab)
- add_ehl_entry (lab, region);
}
-
- /* For sjlj exceptions, need the return label to remain live until
- after landing pad generation. */
- if (USING_SJLJ_EXCEPTIONS && ! crtl->eh.built_landing_pads)
- add_ehl_entry (return_label, NULL);
}
/* Returns true if the current function has exception handling regions. */
}
}
\f
-static hashval_t
-ehl_hash (const void *pentry)
-{
- const struct ehl_map_entry *const entry
- = (const 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 (const void *pentry, const void *pdata)
-{
- const struct ehl_map_entry *const entry
- = (const struct ehl_map_entry *) pentry;
- const struct ehl_map_entry *const data
- = (const struct ehl_map_entry *) pdata;
-
- return entry->label == data->label;
-}
-
/* This section handles removing dead code for flow. */
-/* Remove LABEL from exception_handler_label_map. */
-
-static void
-remove_exception_handler_label (rtx label)
-{
- struct ehl_map_entry **slot, tmp;
-
- /* If exception_handler_label_map was not built yet,
- there is nothing to do. */
- if (crtl->eh.exception_handler_label_map == NULL)
- return;
-
- tmp.label = label;
- slot = (struct ehl_map_entry **)
- htab_find_slot (crtl->eh.exception_handler_label_map, &tmp, NO_INSERT);
- gcc_assert (slot);
-
- htab_clear_slot (crtl->eh.exception_handler_label_map, (void **) slot);
-}
-
/* Splice REGION from the region tree and replace it by REPLACE etc. */
static void
lab = region->landing_pad;
else
lab = region->label;
- if (lab)
- remove_exception_handler_label (lab);
-
if (outer)
pp_start = &outer->inner;
else
remove_eh_handler_and_replace (region, region->outer);
}
-/* LABEL heads a basic block that is about to be deleted. If this
- label corresponds to an exception region, we may be able to
- delete the region. */
-
-void
-maybe_remove_eh_handler (rtx label)
-{
- 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
- landing pad and the post landing pad, and whether an inner try block
- is referencing the catch handlers directly. */
- if (crtl->eh.built_landing_pads)
- return;
-
- tmp.label = label;
- slot = (struct ehl_map_entry **)
- htab_find_slot (crtl->eh.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)
- {
- htab_clear_slot (crtl->eh.exception_handler_label_map, (void **) slot);
- region->label = NULL_RTX;
- }
- else
- remove_eh_handler (region);
-}
-
/* Remove Eh region R that has turned out to have no code in its handler. */
void
void
for_each_eh_label (void (*callback) (rtx))
{
- htab_traverse (crtl->eh.exception_handler_label_map, for_each_eh_label_1,
- (void *) &callback);
-}
-
-static int
-for_each_eh_label_1 (void **pentry, void *data)
-{
- struct ehl_map_entry *entry = *(struct ehl_map_entry **)pentry;
- void (*callback) (rtx) = *(void (**) (rtx)) data;
-
- (*callback) (entry->label);
- return 1;
+ int i;
+ for (i = 0; i < cfun->eh->last_region_number; i++)
+ {
+ struct eh_region *r = VEC_index (eh_region, cfun->eh->region_array, i);
+ if (r && r->region_number == i && r->label
+ && GET_CODE (r->label) == CODE_LABEL)
+ (*callback) (r->label);
+ }
}
/* Invoke CALLBACK for every exception region in the current function. */
static unsigned int
rest_of_handle_eh (void)
{
- cleanup_cfg (CLEANUP_NO_INSN_DEL);
finish_eh_generation ();
cleanup_cfg (CLEANUP_NO_INSN_DEL);
return 0;
projects / platform / upstream / linaro-gcc.git / commitdiff