/* Exception handling semantics and decomposition for trees.
- Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
+the Free Software Foundation; either version 3, or (at your option)
any later version.
GCC is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to
-the Free Software Foundation, 51 Franklin Street, Fifth Floor,
-Boston, MA 02110-1301, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
-#include "rtl.h"
-#include "tm_p.h"
#include "flags.h"
#include "function.h"
#include "except.h"
+#include "pointer-set.h"
#include "tree-flow.h"
#include "tree-dump.h"
#include "tree-inline.h"
#include "langhooks.h"
#include "ggc.h"
#include "toplev.h"
+#include "gimple.h"
+#include "target.h"
+
+/* In some instances a tree and a gimple need to be stored in a same table,
+ i.e. in hash tables. This is a structure to do this. */
+typedef union {tree *tp; tree t; gimple g;} treemple;
-\f
/* Nonzero if we are using EH to handle cleanups. */
static int using_eh_for_cleanups_p = 0;
{
using_eh_for_cleanups_p = 1;
}
-\f
+
/* Misc functions used in this file. */
/* Compare and hash for any structure which begins with a canonical
static int
struct_ptr_eq (const void *a, const void *b)
{
- const void * const * x = a;
- const void * const * y = b;
+ const void * const * x = (const void * const *) a;
+ const void * const * y = (const void * const *) b;
return *x == *y;
}
static hashval_t
struct_ptr_hash (const void *a)
{
- const void * const * x = a;
+ const void * const * x = (const void * const *) a;
return (size_t)*x >> 4;
}
-\f
-/* Remember and lookup EH region data for arbitrary statements.
+
+/* Remember and lookup EH landing pad data for arbitrary statements.
Really this means any statement that could_throw_p. We could
stuff this information into the stmt_ann data structure, but:
compared to those that can. We should be saving some amount
of space by only allocating memory for those that can throw. */
-static void
-record_stmt_eh_region (struct eh_region *region, tree t)
-{
- if (!region)
- return;
-
- add_stmt_to_eh_region (t, get_eh_region_number (region));
-}
+/* Add statement T in function IFUN to landing pad NUM. */
void
-add_stmt_to_eh_region_fn (struct function *ifun, tree t, int num)
+add_stmt_to_eh_lp_fn (struct function *ifun, gimple t, int num)
{
struct throw_stmt_node *n;
void **slot;
- gcc_assert (num >= 0);
- gcc_assert (TREE_CODE (t) != RESX_EXPR);
+ gcc_assert (num != 0);
- n = ggc_alloc (sizeof (*n));
+ n = GGC_NEW (struct throw_stmt_node);
n->stmt = t;
- n->region_nr = num;
+ n->lp_nr = num;
if (!get_eh_throw_stmt_table (ifun))
set_eh_throw_stmt_table (ifun, htab_create_ggc (31, struct_ptr_hash,
slot = htab_find_slot (get_eh_throw_stmt_table (ifun), n, INSERT);
gcc_assert (!*slot);
*slot = n;
- /* ??? For the benefit of calls.c, converting all this to rtl,
- we need to record the call expression, not just the outer
- modify statement. */
- if (TREE_CODE (t) == MODIFY_EXPR
- && (t = get_call_expr_in (t)))
- add_stmt_to_eh_region_fn (ifun, t, num);
}
+/* Add statement T in the current function (cfun) to EH landing pad NUM. */
+
void
-add_stmt_to_eh_region (tree t, int num)
+add_stmt_to_eh_lp (gimple t, int num)
+{
+ add_stmt_to_eh_lp_fn (cfun, t, num);
+}
+
+/* Add statement T to the single EH landing pad in REGION. */
+
+static void
+record_stmt_eh_region (eh_region region, gimple t)
{
- add_stmt_to_eh_region_fn (cfun, t, num);
+ if (region == NULL)
+ return;
+ if (region->type == ERT_MUST_NOT_THROW)
+ add_stmt_to_eh_lp_fn (cfun, t, -region->index);
+ else
+ {
+ eh_landing_pad lp = region->landing_pads;
+ if (lp == NULL)
+ lp = gen_eh_landing_pad (region);
+ else
+ gcc_assert (lp->next_lp == NULL);
+ add_stmt_to_eh_lp_fn (cfun, t, lp->index);
+ }
}
+
+/* Remove statement T in function IFUN from its EH landing pad. */
+
bool
-remove_stmt_from_eh_region_fn (struct function *ifun, tree t)
+remove_stmt_from_eh_lp_fn (struct function *ifun, gimple t)
{
struct throw_stmt_node dummy;
void **slot;
if (slot)
{
htab_clear_slot (get_eh_throw_stmt_table (ifun), slot);
- /* ??? For the benefit of calls.c, converting all this to rtl,
- we need to record the call expression, not just the outer
- modify statement. */
- if (TREE_CODE (t) == MODIFY_EXPR
- && (t = get_call_expr_in (t)))
- remove_stmt_from_eh_region_fn (ifun, t);
return true;
}
else
return false;
}
+
+/* Remove statement T in the current function (cfun) from its
+ EH landing pad. */
+
bool
-remove_stmt_from_eh_region (tree t)
+remove_stmt_from_eh_lp (gimple t)
{
- return remove_stmt_from_eh_region_fn (cfun, t);
+ return remove_stmt_from_eh_lp_fn (cfun, t);
}
+/* Determine if statement T is inside an EH region in function IFUN.
+ Positive numbers indicate a landing pad index; negative numbers
+ indicate a MUST_NOT_THROW region index; zero indicates that the
+ statement is not recorded in the region table. */
+
int
-lookup_stmt_eh_region_fn (struct function *ifun, tree t)
+lookup_stmt_eh_lp_fn (struct function *ifun, gimple t)
{
struct throw_stmt_node *p, n;
- if (!get_eh_throw_stmt_table (ifun))
- return -2;
+ if (ifun->eh->throw_stmt_table == NULL)
+ return 0;
n.stmt = t;
- p = htab_find (get_eh_throw_stmt_table (ifun), &n);
-
- return (p ? p->region_nr : -1);
+ p = (struct throw_stmt_node *) htab_find (ifun->eh->throw_stmt_table, &n);
+ return p ? p->lp_nr : 0;
}
+/* Likewise, but always use the current function. */
+
int
-lookup_stmt_eh_region (tree t)
+lookup_stmt_eh_lp (gimple t)
{
/* We can get called from initialized data when -fnon-call-exceptions
is on; prevent crash. */
if (!cfun)
- return -1;
- return lookup_stmt_eh_region_fn (cfun, t);
+ return 0;
+ return lookup_stmt_eh_lp_fn (cfun, t);
}
-\f
-/* First pass of EH node decomposition. Build up a tree of TRY_FINALLY_EXPR
+/* First pass of EH node decomposition. Build up a tree of GIMPLE_TRY_FINALLY
nodes and LABEL_DECL nodes. We will use this during the second phase to
determine if a goto leaves the body of a TRY_FINALLY_EXPR node. */
struct finally_tree_node
{
- tree child, parent;
+ /* When storing a GIMPLE_TRY, we have to record a gimple. However
+ when deciding whether a GOTO to a certain LABEL_DECL (which is a
+ tree) leaves the TRY block, its necessary to record a tree in
+ this field. Thus a treemple is used. */
+ treemple child;
+ gimple parent;
};
/* Note that this table is *not* marked GTY. It is short-lived. */
static htab_t finally_tree;
static void
-record_in_finally_tree (tree child, tree parent)
+record_in_finally_tree (treemple child, gimple parent)
{
struct finally_tree_node *n;
void **slot;
- n = xmalloc (sizeof (*n));
+ n = XNEW (struct finally_tree_node);
n->child = child;
n->parent = parent;
}
static void
-collect_finally_tree (tree t, tree region)
+collect_finally_tree (gimple stmt, gimple region);
+
+/* Go through the gimple sequence. Works with collect_finally_tree to
+ record all GIMPLE_LABEL and GIMPLE_TRY statements. */
+
+static void
+collect_finally_tree_1 (gimple_seq seq, gimple region)
+{
+ gimple_stmt_iterator gsi;
+
+ for (gsi = gsi_start (seq); !gsi_end_p (gsi); gsi_next (&gsi))
+ collect_finally_tree (gsi_stmt (gsi), region);
+}
+
+static void
+collect_finally_tree (gimple stmt, gimple region)
{
- tailrecurse:
- switch (TREE_CODE (t))
+ treemple temp;
+
+ switch (gimple_code (stmt))
{
- case LABEL_EXPR:
- record_in_finally_tree (LABEL_EXPR_LABEL (t), region);
+ case GIMPLE_LABEL:
+ temp.t = gimple_label_label (stmt);
+ record_in_finally_tree (temp, region);
break;
- case TRY_FINALLY_EXPR:
- record_in_finally_tree (t, region);
- collect_finally_tree (TREE_OPERAND (t, 0), t);
- t = TREE_OPERAND (t, 1);
- goto tailrecurse;
-
- case TRY_CATCH_EXPR:
- collect_finally_tree (TREE_OPERAND (t, 0), region);
- t = TREE_OPERAND (t, 1);
- goto tailrecurse;
-
- case CATCH_EXPR:
- t = CATCH_BODY (t);
- goto tailrecurse;
+ case GIMPLE_TRY:
+ if (gimple_try_kind (stmt) == GIMPLE_TRY_FINALLY)
+ {
+ temp.g = stmt;
+ record_in_finally_tree (temp, region);
+ collect_finally_tree_1 (gimple_try_eval (stmt), stmt);
+ collect_finally_tree_1 (gimple_try_cleanup (stmt), region);
+ }
+ else if (gimple_try_kind (stmt) == GIMPLE_TRY_CATCH)
+ {
+ collect_finally_tree_1 (gimple_try_eval (stmt), region);
+ collect_finally_tree_1 (gimple_try_cleanup (stmt), region);
+ }
+ break;
- case EH_FILTER_EXPR:
- t = EH_FILTER_FAILURE (t);
- goto tailrecurse;
+ case GIMPLE_CATCH:
+ collect_finally_tree_1 (gimple_catch_handler (stmt), region);
+ break;
- case STATEMENT_LIST:
- {
- tree_stmt_iterator i;
- for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
- collect_finally_tree (tsi_stmt (i), region);
- }
+ case GIMPLE_EH_FILTER:
+ collect_finally_tree_1 (gimple_eh_filter_failure (stmt), region);
break;
default:
}
}
+
/* Use the finally tree to determine if a jump from START to TARGET
would leave the try_finally node that START lives in. */
static bool
-outside_finally_tree (tree start, tree target)
+outside_finally_tree (treemple start, gimple target)
{
struct finally_tree_node n, *p;
do
{
n.child = start;
- p = htab_find (finally_tree, &n);
+ p = (struct finally_tree_node *) htab_find (finally_tree, &n);
if (!p)
return true;
- start = p->parent;
+ start.g = p->parent;
}
- while (start != target);
+ while (start.g != target);
return false;
}
-\f
-/* Second pass of EH node decomposition. Actually transform the TRY_FINALLY
- and TRY_CATCH nodes into a set of gotos, magic labels, and eh regions.
+
+/* Second pass of EH node decomposition. Actually transform the GIMPLE_TRY
+ nodes into a set of gotos, magic labels, and eh regions.
The eh region creation is straight-forward, but frobbing all the gotos
and such into shape isn't. */
+/* The sequence into which we record all EH stuff. This will be
+ placed at the end of the function when we're all done. */
+static gimple_seq eh_seq;
+
+/* Record whether an EH region contains something that can throw,
+ indexed by EH region number. */
+static bitmap eh_region_may_contain_throw_map;
+
+/* The GOTO_QUEUE is is an array of GIMPLE_GOTO and GIMPLE_RETURN
+ statements that are seen to escape this GIMPLE_TRY_FINALLY node.
+ The idea is to record a gimple statement for everything except for
+ the conditionals, which get their labels recorded. Since labels are
+ of type 'tree', we need this node to store both gimple and tree
+ objects. REPL_STMT is the sequence used to replace the goto/return
+ statement. CONT_STMT is used to store the statement that allows
+ the return/goto to jump to the original destination. */
+
+struct goto_queue_node
+{
+ treemple stmt;
+ gimple_seq repl_stmt;
+ gimple cont_stmt;
+ int index;
+ /* This is used when index >= 0 to indicate that stmt is a label (as
+ opposed to a goto stmt). */
+ int is_label;
+};
+
/* State of the world while lowering. */
struct leh_state
/* What's "current" while constructing the eh region tree. These
correspond to variables of the same name in cfun->eh, which we
don't have easy access to. */
- struct eh_region *cur_region;
- struct eh_region *prev_try;
+ eh_region cur_region;
+
+ /* What's "current" for the purposes of __builtin_eh_pointer. For
+ a CATCH, this is the associated TRY. For an EH_FILTER, this is
+ the associated ALLOWED_EXCEPTIONS, etc. */
+ eh_region ehp_region;
/* Processing of TRY_FINALLY requires a bit more state. This is
split out into a separate structure so that we don't have to
struct leh_tf_state
{
- /* Pointer to the TRY_FINALLY node under discussion. The try_finally_expr
- is the original TRY_FINALLY_EXPR. We need to retain this so that
- outside_finally_tree can reliably reference the tree used in the
- collect_finally_tree data structures. */
- tree try_finally_expr;
- tree *top_p;
+ /* Pointer to the GIMPLE_TRY_FINALLY node under discussion. The
+ try_finally_expr is the original GIMPLE_TRY_FINALLY. We need to retain
+ this so that outside_finally_tree can reliably reference the tree used
+ in the collect_finally_tree data structures. */
+ gimple try_finally_expr;
+ gimple top_p;
+
+ /* While lowering a top_p usually it is expanded into multiple statements,
+ thus we need the following field to store them. */
+ gimple_seq top_p_seq;
/* The state outside this try_finally node. */
struct leh_state *outer;
/* The exception region created for it. */
- struct eh_region *region;
-
- /* The GOTO_QUEUE is is an array of GOTO_EXPR and RETURN_EXPR statements
- that are seen to escape this TRY_FINALLY_EXPR node. */
- struct goto_queue_node {
- tree stmt;
- tree repl_stmt;
- tree cont_stmt;
- int index;
- } *goto_queue;
+ eh_region region;
+
+ /* The goto queue. */
+ struct goto_queue_node *goto_queue;
size_t goto_queue_size;
size_t goto_queue_active;
+ /* Pointer map to help in searching goto_queue when it is large. */
+ struct pointer_map_t *goto_queue_map;
+
/* The set of unique labels seen as entries in the goto queue. */
VEC(tree,heap) *dest_array;
though subsequent transformations may have cleared that flag. */
tree fallthru_label;
- /* A label that has been registered with except.c to be the
- landing pad for this try block. */
- tree eh_label;
-
/* True if it is possible to fall out the bottom of the try block.
Cleared if the fallthru is converted to a goto. */
bool may_fallthru;
- /* True if any entry in goto_queue is a RETURN_EXPR. */
+ /* True if any entry in goto_queue is a GIMPLE_RETURN. */
bool may_return;
/* True if the finally block can receive an exception edge.
bool may_throw;
};
-static void lower_eh_filter (struct leh_state *, tree *);
-static void lower_eh_constructs_1 (struct leh_state *, tree *);
-
-/* Comparison function for qsort/bsearch. We're interested in
- searching goto queue elements for source statements. */
-
-static int
-goto_queue_cmp (const void *x, const void *y)
-{
- tree a = ((const struct goto_queue_node *)x)->stmt;
- tree b = ((const struct goto_queue_node *)y)->stmt;
- return (a == b ? 0 : a < b ? -1 : 1);
-}
+static gimple_seq lower_eh_must_not_throw (struct leh_state *, gimple);
/* Search for STMT in the goto queue. Return the replacement,
or null if the statement isn't in the queue. */
-static tree
-find_goto_replacement (struct leh_tf_state *tf, tree stmt)
+#define LARGE_GOTO_QUEUE 20
+
+static void lower_eh_constructs_1 (struct leh_state *state, gimple_seq seq);
+
+static gimple_seq
+find_goto_replacement (struct leh_tf_state *tf, treemple stmt)
{
- struct goto_queue_node tmp, *ret;
- tmp.stmt = stmt;
- ret = bsearch (&tmp, tf->goto_queue, tf->goto_queue_active,
- sizeof (struct goto_queue_node), goto_queue_cmp);
- return (ret ? ret->repl_stmt : NULL);
+ unsigned int i;
+ void **slot;
+
+ if (tf->goto_queue_active < LARGE_GOTO_QUEUE)
+ {
+ for (i = 0; i < tf->goto_queue_active; i++)
+ if ( tf->goto_queue[i].stmt.g == stmt.g)
+ return tf->goto_queue[i].repl_stmt;
+ return NULL;
+ }
+
+ /* If we have a large number of entries in the goto_queue, create a
+ pointer map and use that for searching. */
+
+ if (!tf->goto_queue_map)
+ {
+ tf->goto_queue_map = pointer_map_create ();
+ for (i = 0; i < tf->goto_queue_active; i++)
+ {
+ slot = pointer_map_insert (tf->goto_queue_map,
+ tf->goto_queue[i].stmt.g);
+ gcc_assert (*slot == NULL);
+ *slot = &tf->goto_queue[i];
+ }
+ }
+
+ slot = pointer_map_contains (tf->goto_queue_map, stmt.g);
+ if (slot != NULL)
+ return (((struct goto_queue_node *) *slot)->repl_stmt);
+
+ return NULL;
}
/* A subroutine of replace_goto_queue_1. Handles the sub-clauses of a
- lowered COND_EXPR. If, by chance, the replacement is a simple goto,
+ lowered GIMPLE_COND. If, by chance, the replacement is a simple goto,
then we can just splat it in, otherwise we add the new stmts immediately
- after the COND_EXPR and redirect. */
+ after the GIMPLE_COND and redirect. */
static void
replace_goto_queue_cond_clause (tree *tp, struct leh_tf_state *tf,
- tree_stmt_iterator *tsi)
+ gimple_stmt_iterator *gsi)
{
- tree new, one, label;
-
- new = find_goto_replacement (tf, *tp);
- if (!new)
+ tree label;
+ gimple_seq new_seq;
+ treemple temp;
+ location_t loc = gimple_location (gsi_stmt (*gsi));
+
+ temp.tp = tp;
+ new_seq = find_goto_replacement (tf, temp);
+ if (!new_seq)
return;
- one = expr_only (new);
- if (one && TREE_CODE (one) == GOTO_EXPR)
+ if (gimple_seq_singleton_p (new_seq)
+ && gimple_code (gimple_seq_first_stmt (new_seq)) == GIMPLE_GOTO)
{
- *tp = one;
+ *tp = gimple_goto_dest (gimple_seq_first_stmt (new_seq));
return;
}
- label = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
- *tp = build_and_jump (&LABEL_EXPR_LABEL (label));
+ label = create_artificial_label (loc);
+ /* Set the new label for the GIMPLE_COND */
+ *tp = label;
- tsi_link_after (tsi, label, TSI_CONTINUE_LINKING);
- tsi_link_after (tsi, new, TSI_CONTINUE_LINKING);
+ gsi_insert_after (gsi, gimple_build_label (label), GSI_CONTINUE_LINKING);
+ gsi_insert_seq_after (gsi, gimple_seq_copy (new_seq), GSI_CONTINUE_LINKING);
}
/* The real work of replace_goto_queue. Returns with TSI updated to
point to the next statement. */
-static void replace_goto_queue_stmt_list (tree, struct leh_tf_state *);
+static void replace_goto_queue_stmt_list (gimple_seq, struct leh_tf_state *);
static void
-replace_goto_queue_1 (tree t, struct leh_tf_state *tf, tree_stmt_iterator *tsi)
+replace_goto_queue_1 (gimple stmt, struct leh_tf_state *tf,
+ gimple_stmt_iterator *gsi)
{
- switch (TREE_CODE (t))
+ gimple_seq seq;
+ treemple temp;
+ temp.g = NULL;
+
+ switch (gimple_code (stmt))
{
- case GOTO_EXPR:
- case RETURN_EXPR:
- t = find_goto_replacement (tf, t);
- if (t)
+ case GIMPLE_GOTO:
+ case GIMPLE_RETURN:
+ temp.g = stmt;
+ seq = find_goto_replacement (tf, temp);
+ if (seq)
{
- tsi_link_before (tsi, t, TSI_SAME_STMT);
- tsi_delink (tsi);
+ gsi_insert_seq_before (gsi, gimple_seq_copy (seq), GSI_SAME_STMT);
+ gsi_remove (gsi, false);
return;
}
break;
- case COND_EXPR:
- replace_goto_queue_cond_clause (&COND_EXPR_THEN (t), tf, tsi);
- replace_goto_queue_cond_clause (&COND_EXPR_ELSE (t), tf, tsi);
+ case GIMPLE_COND:
+ replace_goto_queue_cond_clause (gimple_op_ptr (stmt, 2), tf, gsi);
+ replace_goto_queue_cond_clause (gimple_op_ptr (stmt, 3), tf, gsi);
break;
- case TRY_FINALLY_EXPR:
- case TRY_CATCH_EXPR:
- replace_goto_queue_stmt_list (TREE_OPERAND (t, 0), tf);
- replace_goto_queue_stmt_list (TREE_OPERAND (t, 1), tf);
+ case GIMPLE_TRY:
+ replace_goto_queue_stmt_list (gimple_try_eval (stmt), tf);
+ replace_goto_queue_stmt_list (gimple_try_cleanup (stmt), tf);
break;
- case CATCH_EXPR:
- replace_goto_queue_stmt_list (CATCH_BODY (t), tf);
+ case GIMPLE_CATCH:
+ replace_goto_queue_stmt_list (gimple_catch_handler (stmt), tf);
break;
- case EH_FILTER_EXPR:
- replace_goto_queue_stmt_list (EH_FILTER_FAILURE (t), tf);
+ case GIMPLE_EH_FILTER:
+ replace_goto_queue_stmt_list (gimple_eh_filter_failure (stmt), tf);
break;
- case STATEMENT_LIST:
- gcc_unreachable ();
-
default:
/* These won't have gotos in them. */
break;
}
- tsi_next (tsi);
+ gsi_next (gsi);
}
-/* A subroutine of replace_goto_queue. Handles STATEMENT_LISTs. */
+/* A subroutine of replace_goto_queue. Handles GIMPLE_SEQ. */
static void
-replace_goto_queue_stmt_list (tree t, struct leh_tf_state *tf)
+replace_goto_queue_stmt_list (gimple_seq seq, struct leh_tf_state *tf)
{
- tree_stmt_iterator i = tsi_start (t);
- while (!tsi_end_p (i))
- replace_goto_queue_1 (tsi_stmt (i), tf, &i);
+ gimple_stmt_iterator gsi = gsi_start (seq);
+
+ while (!gsi_end_p (gsi))
+ replace_goto_queue_1 (gsi_stmt (gsi), tf, &gsi);
}
/* Replace all goto queue members. */
{
if (tf->goto_queue_active == 0)
return;
- replace_goto_queue_stmt_list (*tf->top_p, tf);
+ replace_goto_queue_stmt_list (tf->top_p_seq, tf);
+ replace_goto_queue_stmt_list (eh_seq, tf);
}
-/* For any GOTO_EXPR or RETURN_EXPR, decide whether it leaves a try_finally
- node, and if so record that fact in the goto queue associated with that
- try_finally node. */
+/* Add a new record to the goto queue contained in TF. NEW_STMT is the
+ data to be added, IS_LABEL indicates whether NEW_STMT is a label or
+ a gimple return. */
static void
-maybe_record_in_goto_queue (struct leh_state *state, tree stmt)
+record_in_goto_queue (struct leh_tf_state *tf,
+ treemple new_stmt,
+ int index,
+ bool is_label)
{
- struct leh_tf_state *tf = state->tf;
- struct goto_queue_node *q;
size_t active, size;
- int index;
-
- if (!tf)
- return;
-
- switch (TREE_CODE (stmt))
- {
- case GOTO_EXPR:
- {
- tree lab = GOTO_DESTINATION (stmt);
-
- /* Computed and non-local gotos do not get processed. Given
- their nature we can neither tell whether we've escaped the
- finally block nor redirect them if we knew. */
- if (TREE_CODE (lab) != LABEL_DECL)
- return;
-
- /* No need to record gotos that don't leave the try block. */
- if (! outside_finally_tree (lab, tf->try_finally_expr))
- return;
-
- if (! tf->dest_array)
- {
- tf->dest_array = VEC_alloc (tree, heap, 10);
- VEC_quick_push (tree, tf->dest_array, lab);
- index = 0;
- }
- else
- {
- int n = VEC_length (tree, tf->dest_array);
- for (index = 0; index < n; ++index)
- if (VEC_index (tree, tf->dest_array, index) == lab)
- break;
- if (index == n)
- VEC_safe_push (tree, heap, tf->dest_array, lab);
- }
- }
- break;
-
- case RETURN_EXPR:
- tf->may_return = true;
- index = -1;
- break;
+ struct goto_queue_node *q;
- default:
- gcc_unreachable ();
- }
+ gcc_assert (!tf->goto_queue_map);
active = tf->goto_queue_active;
size = tf->goto_queue_size;
size = (size ? size * 2 : 32);
tf->goto_queue_size = size;
tf->goto_queue
- = xrealloc (tf->goto_queue, size * sizeof (struct goto_queue_node));
+ = XRESIZEVEC (struct goto_queue_node, tf->goto_queue, size);
}
q = &tf->goto_queue[active];
tf->goto_queue_active = active + 1;
memset (q, 0, sizeof (*q));
- q->stmt = stmt;
+ q->stmt = new_stmt;
q->index = index;
+ q->is_label = is_label;
+}
+
+/* Record the LABEL label in the goto queue contained in TF.
+ TF is not null. */
+
+static void
+record_in_goto_queue_label (struct leh_tf_state *tf, treemple stmt, tree label)
+{
+ int index;
+ treemple temp, new_stmt;
+
+ if (!label)
+ return;
+
+ /* Computed and non-local gotos do not get processed. Given
+ their nature we can neither tell whether we've escaped the
+ finally block nor redirect them if we knew. */
+ if (TREE_CODE (label) != LABEL_DECL)
+ return;
+
+ /* No need to record gotos that don't leave the try block. */
+ temp.t = label;
+ if (!outside_finally_tree (temp, tf->try_finally_expr))
+ return;
+
+ if (! tf->dest_array)
+ {
+ tf->dest_array = VEC_alloc (tree, heap, 10);
+ VEC_quick_push (tree, tf->dest_array, label);
+ index = 0;
+ }
+ else
+ {
+ int n = VEC_length (tree, tf->dest_array);
+ for (index = 0; index < n; ++index)
+ if (VEC_index (tree, tf->dest_array, index) == label)
+ break;
+ if (index == n)
+ VEC_safe_push (tree, heap, tf->dest_array, label);
+ }
+
+ /* In the case of a GOTO we want to record the destination label,
+ since with a GIMPLE_COND we have an easy access to the then/else
+ labels. */
+ new_stmt = stmt;
+ record_in_goto_queue (tf, new_stmt, index, true);
+}
+
+/* For any GIMPLE_GOTO or GIMPLE_RETURN, decide whether it leaves a try_finally
+ node, and if so record that fact in the goto queue associated with that
+ try_finally node. */
+
+static void
+maybe_record_in_goto_queue (struct leh_state *state, gimple stmt)
+{
+ struct leh_tf_state *tf = state->tf;
+ treemple new_stmt;
+
+ if (!tf)
+ return;
+
+ switch (gimple_code (stmt))
+ {
+ case GIMPLE_COND:
+ new_stmt.tp = gimple_op_ptr (stmt, 2);
+ record_in_goto_queue_label (tf, new_stmt, gimple_cond_true_label (stmt));
+ new_stmt.tp = gimple_op_ptr (stmt, 3);
+ record_in_goto_queue_label (tf, new_stmt, gimple_cond_false_label (stmt));
+ break;
+ case GIMPLE_GOTO:
+ new_stmt.g = stmt;
+ record_in_goto_queue_label (tf, new_stmt, gimple_goto_dest (stmt));
+ break;
+
+ case GIMPLE_RETURN:
+ tf->may_return = true;
+ new_stmt.g = stmt;
+ record_in_goto_queue (tf, new_stmt, -1, false);
+ break;
+
+ default:
+ gcc_unreachable ();
+ }
}
+
#ifdef ENABLE_CHECKING
-/* We do not process SWITCH_EXPRs for now. As long as the original source
+/* We do not process GIMPLE_SWITCHes for now. As long as the original source
was in fact structured, and we've not yet done jump threading, then none
- of the labels will leave outer TRY_FINALLY_EXPRs. Verify this. */
+ of the labels will leave outer GIMPLE_TRY_FINALLY nodes. Verify this. */
static void
-verify_norecord_switch_expr (struct leh_state *state, tree switch_expr)
+verify_norecord_switch_expr (struct leh_state *state, gimple switch_expr)
{
struct leh_tf_state *tf = state->tf;
size_t i, n;
- tree vec;
if (!tf)
return;
- vec = SWITCH_LABELS (switch_expr);
- n = TREE_VEC_LENGTH (vec);
+ n = gimple_switch_num_labels (switch_expr);
for (i = 0; i < n; ++i)
{
- tree lab = CASE_LABEL (TREE_VEC_ELT (vec, i));
- gcc_assert (!outside_finally_tree (lab, tf->try_finally_expr));
+ treemple temp;
+ tree lab = CASE_LABEL (gimple_switch_label (switch_expr, i));
+ temp.t = lab;
+ gcc_assert (!outside_finally_tree (temp, tf->try_finally_expr));
}
}
#else
variable to be used in manipulating the value returned from the function. */
static void
-do_return_redirection (struct goto_queue_node *q, tree finlab, tree mod,
+do_return_redirection (struct goto_queue_node *q, tree finlab, gimple_seq mod,
tree *return_value_p)
{
- tree ret_expr = TREE_OPERAND (q->stmt, 0);
- tree x;
+ tree ret_expr;
+ gimple x;
+
+ /* In the case of a return, the queue node must be a gimple statement. */
+ gcc_assert (!q->is_label);
+
+ ret_expr = gimple_return_retval (q->stmt.g);
if (ret_expr)
{
+ if (!*return_value_p)
+ *return_value_p = ret_expr;
+ else
+ gcc_assert (*return_value_p == ret_expr);
+ q->cont_stmt = q->stmt.g;
/* The nasty part about redirecting the return value is that the
return value itself is to be computed before the FINALLY block
is executed. e.g.
depends, I guess, but it does make generation of the switch in
lower_try_finally_switch easier. */
- switch (TREE_CODE (ret_expr))
+ if (TREE_CODE (ret_expr) == RESULT_DECL)
{
- case RESULT_DECL:
if (!*return_value_p)
*return_value_p = ret_expr;
else
gcc_assert (*return_value_p == ret_expr);
- q->cont_stmt = q->stmt;
- break;
-
- case MODIFY_EXPR:
- {
- tree result = TREE_OPERAND (ret_expr, 0);
- tree new, old = TREE_OPERAND (ret_expr, 1);
-
- if (!*return_value_p)
- {
- if (aggregate_value_p (TREE_TYPE (result),
- TREE_TYPE (current_function_decl)))
- /* If this function returns in memory, copy the argument
- into the return slot now. Otherwise, we might need to
- worry about magic return semantics, so we need to use a
- temporary to hold the value until we're actually ready
- to return. */
- new = result;
- else
- new = create_tmp_var (TREE_TYPE (old), "rettmp");
- *return_value_p = new;
- }
- else
- new = *return_value_p;
-
- x = build (MODIFY_EXPR, TREE_TYPE (new), new, old);
- append_to_statement_list (x, &q->repl_stmt);
-
- if (new == result)
- x = result;
- else
- x = build (MODIFY_EXPR, TREE_TYPE (result), result, new);
- q->cont_stmt = build1 (RETURN_EXPR, void_type_node, x);
- }
-
- default:
- gcc_unreachable ();
+ q->cont_stmt = q->stmt.g;
}
+ else
+ gcc_unreachable ();
}
else
- {
/* If we don't return a value, all return statements are the same. */
- q->cont_stmt = q->stmt;
- }
+ q->cont_stmt = q->stmt.g;
+
+ if (!q->repl_stmt)
+ q->repl_stmt = gimple_seq_alloc ();
if (mod)
- append_to_statement_list (mod, &q->repl_stmt);
+ gimple_seq_add_seq (&q->repl_stmt, mod);
- x = build1 (GOTO_EXPR, void_type_node, finlab);
- append_to_statement_list (x, &q->repl_stmt);
+ x = gimple_build_goto (finlab);
+ gimple_seq_add_stmt (&q->repl_stmt, x);
}
-/* Similar, but easier, for GOTO_EXPR. */
+/* Similar, but easier, for GIMPLE_GOTO. */
static void
-do_goto_redirection (struct goto_queue_node *q, tree finlab, tree mod)
+do_goto_redirection (struct goto_queue_node *q, tree finlab, gimple_seq mod,
+ struct leh_tf_state *tf)
{
- tree x;
+ gimple x;
+
+ gcc_assert (q->is_label);
+ if (!q->repl_stmt)
+ q->repl_stmt = gimple_seq_alloc ();
+
+ q->cont_stmt = gimple_build_goto (VEC_index (tree, tf->dest_array, q->index));
- q->cont_stmt = q->stmt;
if (mod)
- append_to_statement_list (mod, &q->repl_stmt);
+ gimple_seq_add_seq (&q->repl_stmt, mod);
+
+ x = gimple_build_goto (finlab);
+ gimple_seq_add_stmt (&q->repl_stmt, x);
+}
+
+/* Emit a standard landing pad sequence into SEQ for REGION. */
+
+static void
+emit_post_landing_pad (gimple_seq *seq, eh_region region)
+{
+ eh_landing_pad lp = region->landing_pads;
+ gimple x;
+
+ if (lp == NULL)
+ lp = gen_eh_landing_pad (region);
+
+ lp->post_landing_pad = create_artificial_label (UNKNOWN_LOCATION);
+ EH_LANDING_PAD_NR (lp->post_landing_pad) = lp->index;
+
+ x = gimple_build_label (lp->post_landing_pad);
+ gimple_seq_add_stmt (seq, x);
+}
- x = build1 (GOTO_EXPR, void_type_node, finlab);
- append_to_statement_list (x, &q->repl_stmt);
+/* Emit a RESX statement into SEQ for REGION. */
+
+static void
+emit_resx (gimple_seq *seq, eh_region region)
+{
+ gimple x = gimple_build_resx (region->index);
+ gimple_seq_add_stmt (seq, x);
+ if (region->outer)
+ record_stmt_eh_region (region->outer, x);
+}
+
+/* Emit an EH_DISPATCH statement into SEQ for REGION. */
+
+static void
+emit_eh_dispatch (gimple_seq *seq, eh_region region)
+{
+ gimple x = gimple_build_eh_dispatch (region->index);
+ gimple_seq_add_stmt (seq, x);
+}
+
+/* Note that the current EH region may contain a throw, or a
+ call to a function which itself may contain a throw. */
+
+static void
+note_eh_region_may_contain_throw (eh_region region)
+{
+ while (!bitmap_bit_p (eh_region_may_contain_throw_map, region->index))
+ {
+ bitmap_set_bit (eh_region_may_contain_throw_map, region->index);
+ region = region->outer;
+ if (region == NULL)
+ break;
+ }
+}
+
+/* Check if REGION has been marked as containing a throw. If REGION is
+ NULL, this predicate is false. */
+
+static inline bool
+eh_region_may_contain_throw (eh_region r)
+{
+ return r && bitmap_bit_p (eh_region_may_contain_throw_map, r->index);
}
/* We want to transform
try { body; } catch { stuff; }
to
- body; goto over; lab: stuff; over:
-
- T is a TRY_FINALLY or TRY_CATCH node. LAB is the label that
+ normal_seqence:
+ body;
+ over:
+ eh_seqence:
+ landing_pad:
+ stuff;
+ goto over;
+
+ TP is a GIMPLE_TRY node. REGION is the region whose post_landing_pad
should be placed before the second operand, or NULL. OVER is
an existing label that should be put at the exit, or NULL. */
-static void
-frob_into_branch_around (tree *tp, tree lab, tree over)
+static gimple_seq
+frob_into_branch_around (gimple tp, eh_region region, tree over)
{
- tree x, op1;
+ gimple x;
+ gimple_seq cleanup, result;
+ location_t loc = gimple_location (tp);
- op1 = TREE_OPERAND (*tp, 1);
- *tp = TREE_OPERAND (*tp, 0);
+ cleanup = gimple_try_cleanup (tp);
+ result = gimple_try_eval (tp);
- if (block_may_fallthru (*tp))
- {
- if (!over)
- over = create_artificial_label ();
- x = build1 (GOTO_EXPR, void_type_node, over);
- append_to_statement_list (x, tp);
- }
+ if (region)
+ emit_post_landing_pad (&eh_seq, region);
- if (lab)
+ if (gimple_seq_may_fallthru (cleanup))
{
- x = build1 (LABEL_EXPR, void_type_node, lab);
- append_to_statement_list (x, tp);
+ if (!over)
+ over = create_artificial_label (loc);
+ x = gimple_build_goto (over);
+ gimple_seq_add_stmt (&cleanup, x);
}
-
- append_to_statement_list (op1, tp);
+ gimple_seq_add_seq (&eh_seq, cleanup);
if (over)
{
- x = build1 (LABEL_EXPR, void_type_node, over);
- append_to_statement_list (x, tp);
+ x = gimple_build_label (over);
+ gimple_seq_add_stmt (&result, x);
}
+ return result;
}
/* A subroutine of lower_try_finally. Duplicate the tree rooted at T.
Make sure to record all new labels found. */
-static tree
-lower_try_finally_dup_block (tree t, struct leh_state *outer_state)
+static gimple_seq
+lower_try_finally_dup_block (gimple_seq seq, struct leh_state *outer_state)
{
- tree region = NULL;
+ gimple region = NULL;
+ gimple_seq new_seq;
- t = unsave_expr_now (t);
+ new_seq = copy_gimple_seq_and_replace_locals (seq);
if (outer_state->tf)
region = outer_state->tf->try_finally_expr;
- collect_finally_tree (t, region);
+ collect_finally_tree_1 (new_seq, region);
- return t;
+ return new_seq;
}
/* A subroutine of lower_try_finally. Create a fallthru label for
lower_try_finally_fallthru_label (struct leh_tf_state *tf)
{
tree label = tf->fallthru_label;
+ treemple temp;
+
if (!label)
{
- label = create_artificial_label ();
+ label = create_artificial_label (gimple_location (tf->try_finally_expr));
tf->fallthru_label = label;
if (tf->outer->tf)
- record_in_finally_tree (label, tf->outer->tf->try_finally_expr);
+ {
+ temp.t = label;
+ record_in_finally_tree (temp, tf->outer->tf->try_finally_expr);
+ }
}
return label;
}
struct leh_state *this_state,
struct leh_tf_state *tf)
{
- tree protect_cleanup_actions, finally, x;
- tree_stmt_iterator i;
+ tree protect_cleanup_actions;
+ gimple_stmt_iterator gsi;
bool finally_may_fallthru;
+ gimple_seq finally;
+ gimple x;
/* First check for nothing to do. */
- if (lang_protect_cleanup_actions)
- protect_cleanup_actions = lang_protect_cleanup_actions ();
- else
- protect_cleanup_actions = NULL;
-
- finally = TREE_OPERAND (*tf->top_p, 1);
-
- /* If the EH case of the finally block can fall through, this may be a
- structure of the form
- try {
- try {
- throw ...;
- } cleanup {
- try {
- throw ...;
- } catch (...) {
- }
- }
- } catch (...) {
- yyy;
- }
- E.g. with an inline destructor with an embedded try block. In this
- case we must save the runtime EH data around the nested exception.
-
- This complication means that any time the previous runtime data might
- be used (via fallthru from the finally) we handle the eh case here,
- whether or not protect_cleanup_actions is active. */
-
- finally_may_fallthru = block_may_fallthru (finally);
- if (!finally_may_fallthru && !protect_cleanup_actions)
+ if (lang_protect_cleanup_actions == NULL)
+ return;
+ protect_cleanup_actions = lang_protect_cleanup_actions ();
+ if (protect_cleanup_actions == NULL)
return;
+ finally = gimple_try_cleanup (tf->top_p);
+ finally_may_fallthru = gimple_seq_may_fallthru (finally);
+
/* Duplicate the FINALLY block. Only need to do this for try-finally,
and not for cleanups. */
if (this_state)
finally = lower_try_finally_dup_block (finally, outer_state);
- /* Resume execution after the exception. Adding this now lets
- lower_eh_filter not add unnecessary gotos, as it is clear that
- we never fallthru from this copy of the finally block. */
- if (finally_may_fallthru)
+ /* If this cleanup consists of a TRY_CATCH_EXPR with TRY_CATCH_IS_CLEANUP
+ set, the handler of the TRY_CATCH_EXPR is another cleanup which ought
+ to be in an enclosing scope, but needs to be implemented at this level
+ to avoid a nesting violation (see wrap_temporary_cleanups in
+ cp/decl.c). Since it's logically at an outer level, we should call
+ terminate before we get to it, so strip it away before adding the
+ MUST_NOT_THROW filter. */
+ gsi = gsi_start (finally);
+ x = gsi_stmt (gsi);
+ if (gimple_code (x) == GIMPLE_TRY
+ && gimple_try_kind (x) == GIMPLE_TRY_CATCH
+ && gimple_try_catch_is_cleanup (x))
{
- tree save_eptr, save_filt;
-
- save_eptr = create_tmp_var (ptr_type_node, "save_eptr");
- save_filt = create_tmp_var (integer_type_node, "save_filt");
-
- i = tsi_start (finally);
- x = build (EXC_PTR_EXPR, ptr_type_node);
- x = build (MODIFY_EXPR, void_type_node, save_eptr, x);
- tsi_link_before (&i, x, TSI_CONTINUE_LINKING);
-
- x = build (FILTER_EXPR, integer_type_node);
- x = build (MODIFY_EXPR, void_type_node, save_filt, x);
- tsi_link_before (&i, x, TSI_CONTINUE_LINKING);
-
- i = tsi_last (finally);
- x = build (EXC_PTR_EXPR, ptr_type_node);
- x = build (MODIFY_EXPR, void_type_node, x, save_eptr);
- tsi_link_after (&i, x, TSI_CONTINUE_LINKING);
-
- x = build (FILTER_EXPR, integer_type_node);
- x = build (MODIFY_EXPR, void_type_node, x, save_filt);
- tsi_link_after (&i, x, TSI_CONTINUE_LINKING);
-
- x = build_resx (get_eh_region_number (tf->region));
- tsi_link_after (&i, x, TSI_CONTINUE_LINKING);
+ gsi_insert_seq_before (&gsi, gimple_try_eval (x), GSI_SAME_STMT);
+ gsi_remove (&gsi, false);
}
/* Wrap the block with protect_cleanup_actions as the action. */
- if (protect_cleanup_actions)
- {
- x = build (EH_FILTER_EXPR, void_type_node, NULL, NULL);
- append_to_statement_list (protect_cleanup_actions, &EH_FILTER_FAILURE (x));
- EH_FILTER_MUST_NOT_THROW (x) = 1;
- finally = build (TRY_CATCH_EXPR, void_type_node, finally, x);
- lower_eh_filter (outer_state, &finally);
- }
- else
- lower_eh_constructs_1 (outer_state, &finally);
-
- /* Hook this up to the end of the existing try block. If we
- previously fell through the end, we'll have to branch around.
- This means adding a new goto, and adding it to the queue. */
-
- i = tsi_last (TREE_OPERAND (*tf->top_p, 0));
-
- if (tf->may_fallthru)
- {
- x = lower_try_finally_fallthru_label (tf);
- x = build1 (GOTO_EXPR, void_type_node, x);
- tsi_link_after (&i, x, TSI_CONTINUE_LINKING);
-
- if (this_state)
- maybe_record_in_goto_queue (this_state, x);
-
- tf->may_fallthru = false;
- }
-
- x = build1 (LABEL_EXPR, void_type_node, tf->eh_label);
- tsi_link_after (&i, x, TSI_CONTINUE_LINKING);
- tsi_link_after (&i, finally, TSI_CONTINUE_LINKING);
+ x = gimple_build_eh_must_not_throw (protect_cleanup_actions);
+ x = gimple_build_try (finally, gimple_seq_alloc_with_stmt (x),
+ GIMPLE_TRY_CATCH);
+ finally = lower_eh_must_not_throw (outer_state, x);
+
+ /* Drop all of this into the exception sequence. */
+ emit_post_landing_pad (&eh_seq, tf->region);
+ gimple_seq_add_seq (&eh_seq, finally);
+ if (finally_may_fallthru)
+ emit_resx (&eh_seq, tf->region);
/* Having now been handled, EH isn't to be considered with
the rest of the outgoing edges. */
try_finally node for this special case. */
static void
-lower_try_finally_nofallthru (struct leh_state *state, struct leh_tf_state *tf)
+lower_try_finally_nofallthru (struct leh_state *state,
+ struct leh_tf_state *tf)
{
- tree x, finally, lab, return_val;
+ tree lab, return_val;
+ gimple x;
+ gimple_seq finally;
struct goto_queue_node *q, *qe;
- if (tf->may_throw)
- lab = tf->eh_label;
- else
- lab = create_artificial_label ();
+ lab = create_artificial_label (gimple_location (tf->try_finally_expr));
- finally = TREE_OPERAND (*tf->top_p, 1);
- *tf->top_p = TREE_OPERAND (*tf->top_p, 0);
+ /* We expect that tf->top_p is a GIMPLE_TRY. */
+ finally = gimple_try_cleanup (tf->top_p);
+ tf->top_p_seq = gimple_try_eval (tf->top_p);
- x = build1 (LABEL_EXPR, void_type_node, lab);
- append_to_statement_list (x, tf->top_p);
+ x = gimple_build_label (lab);
+ gimple_seq_add_stmt (&tf->top_p_seq, x);
return_val = NULL;
q = tf->goto_queue;
if (q->index < 0)
do_return_redirection (q, lab, NULL, &return_val);
else
- do_goto_redirection (q, lab, NULL);
+ do_goto_redirection (q, lab, NULL, tf);
replace_goto_queue (tf);
- lower_eh_constructs_1 (state, &finally);
- append_to_statement_list (finally, tf->top_p);
-}
+ lower_eh_constructs_1 (state, finally);
+ gimple_seq_add_seq (&tf->top_p_seq, finally);
-/* A subroutine of lower_try_finally. We have determined that there is
- exactly one destination of the finally block. Restructure the
+ if (tf->may_throw)
+ {
+ emit_post_landing_pad (&eh_seq, tf->region);
+
+ x = gimple_build_goto (lab);
+ gimple_seq_add_stmt (&eh_seq, x);
+ }
+}
+
+/* A subroutine of lower_try_finally. We have determined that there is
+ exactly one destination of the finally block. Restructure the
try_finally node for this special case. */
static void
lower_try_finally_onedest (struct leh_state *state, struct leh_tf_state *tf)
{
struct goto_queue_node *q, *qe;
- tree x, finally, finally_label;
+ gimple x;
+ gimple_seq finally;
+ tree finally_label;
+ location_t loc = gimple_location (tf->try_finally_expr);
- finally = TREE_OPERAND (*tf->top_p, 1);
- *tf->top_p = TREE_OPERAND (*tf->top_p, 0);
+ finally = gimple_try_cleanup (tf->top_p);
+ tf->top_p_seq = gimple_try_eval (tf->top_p);
- lower_eh_constructs_1 (state, &finally);
+ lower_eh_constructs_1 (state, finally);
if (tf->may_throw)
{
/* Only reachable via the exception edge. Add the given label to
the head of the FINALLY block. Append a RESX at the end. */
-
- x = build1 (LABEL_EXPR, void_type_node, tf->eh_label);
- append_to_statement_list (x, tf->top_p);
-
- append_to_statement_list (finally, tf->top_p);
-
- x = build_resx (get_eh_region_number (tf->region));
-
- append_to_statement_list (x, tf->top_p);
-
+ emit_post_landing_pad (&eh_seq, tf->region);
+ gimple_seq_add_seq (&eh_seq, finally);
+ emit_resx (&eh_seq, tf->region);
return;
}
{
/* Only reachable via the fallthru edge. Do nothing but let
the two blocks run together; we'll fall out the bottom. */
- append_to_statement_list (finally, tf->top_p);
+ gimple_seq_add_seq (&tf->top_p_seq, finally);
return;
}
- finally_label = create_artificial_label ();
- x = build1 (LABEL_EXPR, void_type_node, finally_label);
- append_to_statement_list (x, tf->top_p);
+ finally_label = create_artificial_label (loc);
+ x = gimple_build_label (finally_label);
+ gimple_seq_add_stmt (&tf->top_p_seq, x);
- append_to_statement_list (finally, tf->top_p);
+ gimple_seq_add_seq (&tf->top_p_seq, finally);
q = tf->goto_queue;
qe = q + tf->goto_queue_active;
{
/* Reachable by goto expressions only. Redirect them. */
for (; q < qe; ++q)
- do_goto_redirection (q, finally_label, NULL);
+ do_goto_redirection (q, finally_label, NULL, tf);
replace_goto_queue (tf);
if (VEC_index (tree, tf->dest_array, 0) == tf->fallthru_label)
}
}
- append_to_statement_list (tf->goto_queue[0].cont_stmt, tf->top_p);
- maybe_record_in_goto_queue (state, tf->goto_queue[0].cont_stmt);
+ /* Place the original return/goto to the original destination
+ immediately after the finally block. */
+ x = tf->goto_queue[0].cont_stmt;
+ gimple_seq_add_stmt (&tf->top_p_seq, x);
+ maybe_record_in_goto_queue (state, x);
}
/* A subroutine of lower_try_finally. There are multiple edges incoming
static void
lower_try_finally_copy (struct leh_state *state, struct leh_tf_state *tf)
{
- tree finally, new_stmt;
- tree x;
-
- finally = TREE_OPERAND (*tf->top_p, 1);
- *tf->top_p = TREE_OPERAND (*tf->top_p, 0);
+ gimple_seq finally;
+ gimple_seq new_stmt;
+ gimple_seq seq;
+ gimple x;
+ tree tmp;
+ location_t tf_loc = gimple_location (tf->try_finally_expr);
- new_stmt = NULL_TREE;
+ finally = gimple_try_cleanup (tf->top_p);
+ tf->top_p_seq = gimple_try_eval (tf->top_p);
+ new_stmt = NULL;
if (tf->may_fallthru)
{
- x = lower_try_finally_dup_block (finally, state);
- lower_eh_constructs_1 (state, &x);
- append_to_statement_list (x, &new_stmt);
+ seq = lower_try_finally_dup_block (finally, state);
+ lower_eh_constructs_1 (state, seq);
+ gimple_seq_add_seq (&new_stmt, seq);
- x = lower_try_finally_fallthru_label (tf);
- x = build1 (GOTO_EXPR, void_type_node, x);
- append_to_statement_list (x, &new_stmt);
+ tmp = lower_try_finally_fallthru_label (tf);
+ x = gimple_build_goto (tmp);
+ gimple_seq_add_stmt (&new_stmt, x);
}
if (tf->may_throw)
{
- x = build1 (LABEL_EXPR, void_type_node, tf->eh_label);
- append_to_statement_list (x, &new_stmt);
+ seq = lower_try_finally_dup_block (finally, state);
+ lower_eh_constructs_1 (state, seq);
- x = lower_try_finally_dup_block (finally, state);
- lower_eh_constructs_1 (state, &x);
- append_to_statement_list (x, &new_stmt);
-
- x = build_resx (get_eh_region_number (tf->region));
- append_to_statement_list (x, &new_stmt);
+ emit_post_landing_pad (&eh_seq, tf->region);
+ gimple_seq_add_seq (&eh_seq, seq);
+ emit_resx (&eh_seq, tf->region);
}
if (tf->goto_queue)
struct goto_queue_node *q, *qe;
tree return_val = NULL;
int return_index, index;
- struct
+ struct labels_s
{
struct goto_queue_node *q;
tree label;
} *labels;
return_index = VEC_length (tree, tf->dest_array);
- labels = xcalloc (sizeof (*labels), return_index + 1);
+ labels = XCNEWVEC (struct labels_s, return_index + 1);
q = tf->goto_queue;
qe = q + tf->goto_queue_active;
if (! q)
continue;
- lab = labels[index].label = create_artificial_label ();
+ lab = labels[index].label
+ = create_artificial_label (tf_loc);
if (index == return_index)
do_return_redirection (q, lab, NULL, &return_val);
else
- do_goto_redirection (q, lab, NULL);
+ do_goto_redirection (q, lab, NULL, tf);
- x = build1 (LABEL_EXPR, void_type_node, lab);
- append_to_statement_list (x, &new_stmt);
+ x = gimple_build_label (lab);
+ gimple_seq_add_stmt (&new_stmt, x);
- x = lower_try_finally_dup_block (finally, state);
- lower_eh_constructs_1 (state, &x);
- append_to_statement_list (x, &new_stmt);
+ seq = lower_try_finally_dup_block (finally, state);
+ lower_eh_constructs_1 (state, seq);
+ gimple_seq_add_seq (&new_stmt, seq);
- append_to_statement_list (q->cont_stmt, &new_stmt);
+ gimple_seq_add_stmt (&new_stmt, q->cont_stmt);
maybe_record_in_goto_queue (state, q->cont_stmt);
}
if (index == return_index)
do_return_redirection (q, lab, NULL, &return_val);
else
- do_goto_redirection (q, lab, NULL);
+ do_goto_redirection (q, lab, NULL, tf);
}
-
+
replace_goto_queue (tf);
free (labels);
}
/* Need to link new stmts after running replace_goto_queue due
to not wanting to process the same goto stmts twice. */
- append_to_statement_list (new_stmt, tf->top_p);
+ gimple_seq_add_seq (&tf->top_p_seq, new_stmt);
}
/* A subroutine of lower_try_finally. There are multiple edges incoming
{
struct goto_queue_node *q, *qe;
tree return_val = NULL;
- tree finally, finally_tmp, finally_label;
+ tree finally_tmp, finally_label;
int return_index, eh_index, fallthru_index;
int nlabels, ndests, j, last_case_index;
- tree case_label_vec, switch_stmt, last_case, switch_body;
- tree x;
+ tree last_case;
+ VEC (tree,heap) *case_label_vec;
+ gimple_seq switch_body;
+ gimple x;
+ tree tmp;
+ gimple switch_stmt;
+ gimple_seq finally;
+ struct pointer_map_t *cont_map = NULL;
+ /* The location of the TRY_FINALLY stmt. */
+ location_t tf_loc = gimple_location (tf->try_finally_expr);
+ /* The location of the finally block. */
+ location_t finally_loc;
+
+ switch_body = gimple_seq_alloc ();
/* Mash the TRY block to the head of the chain. */
- finally = TREE_OPERAND (*tf->top_p, 1);
- *tf->top_p = TREE_OPERAND (*tf->top_p, 0);
+ finally = gimple_try_cleanup (tf->top_p);
+ tf->top_p_seq = gimple_try_eval (tf->top_p);
+
+ /* The location of the finally is either the last stmt in the finally
+ block or the location of the TRY_FINALLY itself. */
+ finally_loc = gimple_seq_last_stmt (tf->top_p_seq) != NULL ?
+ gimple_location (gimple_seq_last_stmt (tf->top_p_seq))
+ : tf_loc;
/* Lower the finally block itself. */
- lower_eh_constructs_1 (state, &finally);
+ lower_eh_constructs_1 (state, finally);
/* Prepare for switch statement generation. */
nlabels = VEC_length (tree, tf->dest_array);
ndests = fallthru_index + tf->may_fallthru;
finally_tmp = create_tmp_var (integer_type_node, "finally_tmp");
- finally_label = create_artificial_label ();
+ finally_label = create_artificial_label (finally_loc);
- case_label_vec = make_tree_vec (ndests);
- switch_stmt = build (SWITCH_EXPR, integer_type_node, finally_tmp,
- NULL_TREE, case_label_vec);
- switch_body = NULL;
+ /* We use VEC_quick_push on case_label_vec throughout this function,
+ since we know the size in advance and allocate precisely as muce
+ space as needed. */
+ case_label_vec = VEC_alloc (tree, heap, ndests);
last_case = NULL;
last_case_index = 0;
if (tf->may_fallthru)
{
- x = build (MODIFY_EXPR, void_type_node, finally_tmp,
- build_int_cst (NULL_TREE, fallthru_index));
- append_to_statement_list (x, tf->top_p);
-
- if (tf->may_throw)
- {
- x = build1 (GOTO_EXPR, void_type_node, finally_label);
- append_to_statement_list (x, tf->top_p);
- }
-
-
- last_case = build (CASE_LABEL_EXPR, void_type_node,
- build_int_cst (NULL_TREE, fallthru_index), NULL,
- create_artificial_label ());
- TREE_VEC_ELT (case_label_vec, last_case_index) = last_case;
+ x = gimple_build_assign (finally_tmp,
+ build_int_cst (NULL, fallthru_index));
+ gimple_seq_add_stmt (&tf->top_p_seq, x);
+
+ last_case = build3 (CASE_LABEL_EXPR, void_type_node,
+ build_int_cst (NULL, fallthru_index),
+ NULL, create_artificial_label (tf_loc));
+ VEC_quick_push (tree, case_label_vec, last_case);
last_case_index++;
- x = build (LABEL_EXPR, void_type_node, CASE_LABEL (last_case));
- append_to_statement_list (x, &switch_body);
+ x = gimple_build_label (CASE_LABEL (last_case));
+ gimple_seq_add_stmt (&switch_body, x);
- x = lower_try_finally_fallthru_label (tf);
- x = build1 (GOTO_EXPR, void_type_node, x);
- append_to_statement_list (x, &switch_body);
+ tmp = lower_try_finally_fallthru_label (tf);
+ x = gimple_build_goto (tmp);
+ gimple_seq_add_stmt (&switch_body, x);
}
if (tf->may_throw)
{
- x = build1 (LABEL_EXPR, void_type_node, tf->eh_label);
- append_to_statement_list (x, tf->top_p);
+ emit_post_landing_pad (&eh_seq, tf->region);
- x = build (MODIFY_EXPR, void_type_node, finally_tmp,
- build_int_cst (NULL_TREE, eh_index));
- append_to_statement_list (x, tf->top_p);
+ x = gimple_build_assign (finally_tmp,
+ build_int_cst (NULL, eh_index));
+ gimple_seq_add_stmt (&eh_seq, x);
- last_case = build (CASE_LABEL_EXPR, void_type_node,
- build_int_cst (NULL_TREE, eh_index), NULL,
- create_artificial_label ());
- TREE_VEC_ELT (case_label_vec, last_case_index) = last_case;
+ x = gimple_build_goto (finally_label);
+ gimple_seq_add_stmt (&eh_seq, x);
+
+ last_case = build3 (CASE_LABEL_EXPR, void_type_node,
+ build_int_cst (NULL, eh_index),
+ NULL, create_artificial_label (tf_loc));
+ VEC_quick_push (tree, case_label_vec, last_case);
last_case_index++;
- x = build (LABEL_EXPR, void_type_node, CASE_LABEL (last_case));
- append_to_statement_list (x, &switch_body);
- x = build_resx (get_eh_region_number (tf->region));
- append_to_statement_list (x, &switch_body);
+ x = gimple_build_label (CASE_LABEL (last_case));
+ gimple_seq_add_stmt (&eh_seq, x);
+ emit_resx (&eh_seq, tf->region);
}
- x = build1 (LABEL_EXPR, void_type_node, finally_label);
- append_to_statement_list (x, tf->top_p);
+ x = gimple_build_label (finally_label);
+ gimple_seq_add_stmt (&tf->top_p_seq, x);
- append_to_statement_list (finally, tf->top_p);
+ gimple_seq_add_seq (&tf->top_p_seq, finally);
/* Redirect each incoming goto edge. */
q = tf->goto_queue;
qe = q + tf->goto_queue_active;
j = last_case_index + tf->may_return;
+ /* Prepare the assignments to finally_tmp that are executed upon the
+ entrance through a particular edge. */
for (; q < qe; ++q)
{
- tree mod;
- int switch_id, case_index;
+ gimple_seq mod;
+ int switch_id;
+ unsigned int case_index;
+
+ mod = gimple_seq_alloc ();
if (q->index < 0)
{
- mod = build (MODIFY_EXPR, void_type_node, finally_tmp,
- build_int_cst (NULL_TREE, return_index));
+ x = gimple_build_assign (finally_tmp,
+ build_int_cst (NULL, return_index));
+ gimple_seq_add_stmt (&mod, x);
do_return_redirection (q, finally_label, mod, &return_val);
switch_id = return_index;
}
else
{
- mod = build (MODIFY_EXPR, void_type_node, finally_tmp,
- build_int_cst (NULL_TREE, q->index));
- do_goto_redirection (q, finally_label, mod);
+ x = gimple_build_assign (finally_tmp,
+ build_int_cst (NULL, q->index));
+ gimple_seq_add_stmt (&mod, x);
+ do_goto_redirection (q, finally_label, mod, tf);
switch_id = q->index;
}
case_index = j + q->index;
- if (!TREE_VEC_ELT (case_label_vec, case_index))
- TREE_VEC_ELT (case_label_vec, case_index)
- = build (CASE_LABEL_EXPR, void_type_node,
- build_int_cst (NULL_TREE, switch_id), NULL,
- /* We store the cont_stmt in the
- CASE_LABEL, so that we can recover it
- in the loop below. We don't create
- the new label while walking the
- goto_queue because pointers don't
- offer a stable order. */
- q->cont_stmt);
+ if (VEC_length (tree, case_label_vec) <= case_index
+ || !VEC_index (tree, case_label_vec, case_index))
+ {
+ tree case_lab;
+ void **slot;
+ case_lab = build3 (CASE_LABEL_EXPR, void_type_node,
+ build_int_cst (NULL, switch_id),
+ NULL, NULL);
+ /* We store the cont_stmt in the pointer map, so that we can recover
+ it in the loop below. We don't create the new label while
+ walking the goto_queue because pointers don't offer a stable
+ order. */
+ if (!cont_map)
+ cont_map = pointer_map_create ();
+ slot = pointer_map_insert (cont_map, case_lab);
+ *slot = q->cont_stmt;
+ VEC_quick_push (tree, case_label_vec, case_lab);
+ }
}
for (j = last_case_index; j < last_case_index + nlabels; j++)
{
tree label;
- tree cont_stmt;
+ gimple cont_stmt;
+ void **slot;
- last_case = TREE_VEC_ELT (case_label_vec, j);
+ last_case = VEC_index (tree, case_label_vec, j);
gcc_assert (last_case);
+ gcc_assert (cont_map);
- cont_stmt = CASE_LABEL (last_case);
+ slot = pointer_map_contains (cont_map, last_case);
+ /* As the comment above suggests, CASE_LABEL (last_case) was just a
+ placeholder, it does not store an actual label, yet. */
+ gcc_assert (slot);
+ cont_stmt = *(gimple *) slot;
- label = create_artificial_label ();
+ label = create_artificial_label (tf_loc);
CASE_LABEL (last_case) = label;
- x = build (LABEL_EXPR, void_type_node, label);
- append_to_statement_list (x, &switch_body);
- append_to_statement_list (cont_stmt, &switch_body);
+ x = gimple_build_label (label);
+ gimple_seq_add_stmt (&switch_body, x);
+ gimple_seq_add_stmt (&switch_body, cont_stmt);
maybe_record_in_goto_queue (state, cont_stmt);
}
+ if (cont_map)
+ pointer_map_destroy (cont_map);
+
replace_goto_queue (tf);
/* Make sure that the last case is the default label, as one is required.
CASE_LOW (last_case) = NULL;
sort_case_labels (case_label_vec);
- /* Need to link switch_stmt after running replace_goto_queue due
- to not wanting to process the same goto stmts twice. */
- append_to_statement_list (switch_stmt, tf->top_p);
- append_to_statement_list (switch_body, tf->top_p);
+ /* Build the switch statement, setting last_case to be the default
+ label. */
+ switch_stmt = gimple_build_switch_vec (finally_tmp, last_case,
+ case_label_vec);
+ gimple_set_location (switch_stmt, finally_loc);
+
+ /* Need to link SWITCH_STMT after running replace_goto_queue
+ due to not wanting to process the same goto stmts twice. */
+ gimple_seq_add_stmt (&tf->top_p_seq, switch_stmt);
+ gimple_seq_add_seq (&tf->top_p_seq, switch_body);
}
/* Decide whether or not we are going to duplicate the finally block.
the estimate of the size of the switch machinery we'd have to add. */
static bool
-decide_copy_try_finally (int ndests, tree finally)
+decide_copy_try_finally (int ndests, gimple_seq finally)
{
int f_estimate, sw_estimate;
return false;
/* Finally estimate N times, plus N gotos. */
- f_estimate = estimate_num_insns (finally);
+ f_estimate = count_insns_seq (finally, &eni_size_weights);
f_estimate = (f_estimate + 1) * ndests;
/* Switch statement (cost 10), N variable assignments, N gotos. */
sw_estimate = 10 + 2 * ndests;
/* Optimize for size clearly wants our best guess. */
- if (optimize_size)
+ if (optimize_function_for_size_p (cfun))
return f_estimate < sw_estimate;
/* ??? These numbers are completely made up so far. */
return f_estimate < 40 || f_estimate * 2 < sw_estimate * 3;
}
-/* A subroutine of lower_eh_constructs_1. Lower a TRY_FINALLY_EXPR nodes
+/* REG is the enclosing region for a possible cleanup region, or the region
+ itself. Returns TRUE if such a region would be unreachable.
+
+ Cleanup regions within a must-not-throw region aren't actually reachable
+ even if there are throwing stmts within them, because the personality
+ routine will call terminate before unwinding. */
+
+static bool
+cleanup_is_dead_in (eh_region reg)
+{
+ while (reg && reg->type == ERT_CLEANUP)
+ reg = reg->outer;
+ return (reg && reg->type == ERT_MUST_NOT_THROW);
+}
+
+/* A subroutine of lower_eh_constructs_1. Lower a GIMPLE_TRY_FINALLY nodes
to a sequence of labels and blocks, plus the exception region trees
that record all the magic. This is complicated by the need to
arrange for the FINALLY block to be executed on all exits. */
-static void
-lower_try_finally (struct leh_state *state, tree *tp)
+static gimple_seq
+lower_try_finally (struct leh_state *state, gimple tp)
{
struct leh_tf_state this_tf;
struct leh_state this_state;
int ndests;
+ gimple_seq old_eh_seq;
/* Process the try block. */
memset (&this_tf, 0, sizeof (this_tf));
- this_tf.try_finally_expr = *tp;
+ this_tf.try_finally_expr = tp;
this_tf.top_p = tp;
this_tf.outer = state;
- if (using_eh_for_cleanups_p)
- this_tf.region
- = gen_eh_region_cleanup (state->cur_region, state->prev_try);
+ if (using_eh_for_cleanups_p && !cleanup_is_dead_in (state->cur_region))
+ {
+ this_tf.region = gen_eh_region_cleanup (state->cur_region);
+ this_state.cur_region = this_tf.region;
+ }
else
- this_tf.region = NULL;
+ {
+ this_tf.region = NULL;
+ this_state.cur_region = state->cur_region;
+ }
- this_state.cur_region = this_tf.region;
- this_state.prev_try = state->prev_try;
+ this_state.ehp_region = state->ehp_region;
this_state.tf = &this_tf;
- lower_eh_constructs_1 (&this_state, &TREE_OPERAND (*tp, 0));
+ old_eh_seq = eh_seq;
+ eh_seq = NULL;
+
+ lower_eh_constructs_1 (&this_state, gimple_try_eval(tp));
/* Determine if the try block is escaped through the bottom. */
- this_tf.may_fallthru = block_may_fallthru (TREE_OPERAND (*tp, 0));
+ this_tf.may_fallthru = gimple_seq_may_fallthru (gimple_try_eval (tp));
/* Determine if any exceptions are possible within the try block. */
- if (using_eh_for_cleanups_p)
- this_tf.may_throw = get_eh_region_may_contain_throw (this_tf.region);
+ if (this_tf.region)
+ this_tf.may_throw = eh_region_may_contain_throw (this_tf.region);
if (this_tf.may_throw)
- {
- this_tf.eh_label = create_artificial_label ();
- set_eh_region_tree_label (this_tf.region, this_tf.eh_label);
- honor_protect_cleanup_actions (state, &this_state, &this_tf);
- }
-
- /* Sort the goto queue for efficient searching later. */
- if (this_tf.goto_queue_active > 1)
- qsort (this_tf.goto_queue, this_tf.goto_queue_active,
- sizeof (struct goto_queue_node), goto_queue_cmp);
+ honor_protect_cleanup_actions (state, &this_state, &this_tf);
/* Determine how many edges (still) reach the finally block. Or rather,
how many destinations are reached by the finally block. Use this to
/* If the FINALLY block is not reachable, dike it out. */
if (ndests == 0)
- *tp = TREE_OPERAND (*tp, 0);
-
+ {
+ gimple_seq_add_seq (&this_tf.top_p_seq, gimple_try_eval (tp));
+ gimple_try_set_cleanup (tp, NULL);
+ }
/* If the finally block doesn't fall through, then any destination
we might try to impose there isn't reached either. There may be
some minor amount of cleanup and redirection still needed. */
- else if (!block_may_fallthru (TREE_OPERAND (*tp, 1)))
+ else if (!gimple_seq_may_fallthru (gimple_try_cleanup (tp)))
lower_try_finally_nofallthru (state, &this_tf);
/* We can easily special-case redirection to a single destination. */
else if (ndests == 1)
lower_try_finally_onedest (state, &this_tf);
-
- else if (decide_copy_try_finally (ndests, TREE_OPERAND (*tp, 1)))
+ else if (decide_copy_try_finally (ndests, gimple_try_cleanup (tp)))
lower_try_finally_copy (state, &this_tf);
else
lower_try_finally_switch (state, &this_tf);
block, do so. */
if (this_tf.fallthru_label)
{
- tree x = build1 (LABEL_EXPR, void_type_node, this_tf.fallthru_label);
- append_to_statement_list (x, tp);
+ /* This must be reached only if ndests == 0. */
+ gimple x = gimple_build_label (this_tf.fallthru_label);
+ gimple_seq_add_stmt (&this_tf.top_p_seq, x);
}
VEC_free (tree, heap, this_tf.dest_array);
if (this_tf.goto_queue)
free (this_tf.goto_queue);
+ if (this_tf.goto_queue_map)
+ pointer_map_destroy (this_tf.goto_queue_map);
+
+ /* If there was an old (aka outer) eh_seq, append the current eh_seq.
+ If there was no old eh_seq, then the append is trivially already done. */
+ if (old_eh_seq)
+ {
+ if (eh_seq == NULL)
+ eh_seq = old_eh_seq;
+ else
+ {
+ gimple_seq new_eh_seq = eh_seq;
+ eh_seq = old_eh_seq;
+ gimple_seq_add_seq(&eh_seq, new_eh_seq);
+ }
+ }
+
+ return this_tf.top_p_seq;
}
-/* A subroutine of lower_eh_constructs_1. Lower a TRY_CATCH_EXPR with a
- list of CATCH_EXPR nodes to a sequence of labels and blocks, plus the
- exception region trees that record all the magic. */
+/* A subroutine of lower_eh_constructs_1. Lower a GIMPLE_TRY_CATCH with a
+ list of GIMPLE_CATCH to a sequence of labels and blocks, plus the
+ exception region trees that records all the magic. */
-static void
-lower_catch (struct leh_state *state, tree *tp)
+static gimple_seq
+lower_catch (struct leh_state *state, gimple tp)
{
- struct eh_region *try_region;
- struct leh_state this_state;
- tree_stmt_iterator i;
+ eh_region try_region = NULL;
+ struct leh_state this_state = *state;
+ gimple_stmt_iterator gsi;
tree out_label;
+ gimple_seq new_seq;
+ gimple x;
+ location_t try_catch_loc = gimple_location (tp);
- try_region = gen_eh_region_try (state->cur_region);
- this_state.cur_region = try_region;
- this_state.prev_try = try_region;
- this_state.tf = state->tf;
-
- lower_eh_constructs_1 (&this_state, &TREE_OPERAND (*tp, 0));
-
- if (!get_eh_region_may_contain_throw (try_region))
+ if (flag_exceptions)
{
- *tp = TREE_OPERAND (*tp, 0);
- return;
+ try_region = gen_eh_region_try (state->cur_region);
+ this_state.cur_region = try_region;
}
+ lower_eh_constructs_1 (&this_state, gimple_try_eval (tp));
+
+ if (!eh_region_may_contain_throw (try_region))
+ return gimple_try_eval (tp);
+
+ new_seq = NULL;
+ emit_eh_dispatch (&new_seq, try_region);
+ emit_resx (&new_seq, try_region);
+
+ this_state.cur_region = state->cur_region;
+ this_state.ehp_region = try_region;
+
out_label = NULL;
- for (i = tsi_start (TREE_OPERAND (*tp, 1)); !tsi_end_p (i); )
+ for (gsi = gsi_start (gimple_try_cleanup (tp));
+ !gsi_end_p (gsi);
+ gsi_next (&gsi))
{
- struct eh_region *catch_region;
- tree catch, x, eh_label;
+ eh_catch c;
+ gimple gcatch;
+ gimple_seq handler;
- catch = tsi_stmt (i);
- catch_region = gen_eh_region_catch (try_region, CATCH_TYPES (catch));
+ gcatch = gsi_stmt (gsi);
+ c = gen_eh_region_catch (try_region, gimple_catch_types (gcatch));
- this_state.cur_region = catch_region;
- this_state.prev_try = state->prev_try;
- lower_eh_constructs_1 (&this_state, &CATCH_BODY (catch));
+ handler = gimple_catch_handler (gcatch);
+ lower_eh_constructs_1 (&this_state, handler);
- eh_label = create_artificial_label ();
- set_eh_region_tree_label (catch_region, eh_label);
+ c->label = create_artificial_label (UNKNOWN_LOCATION);
+ x = gimple_build_label (c->label);
+ gimple_seq_add_stmt (&new_seq, x);
- x = build1 (LABEL_EXPR, void_type_node, eh_label);
- tsi_link_before (&i, x, TSI_SAME_STMT);
+ gimple_seq_add_seq (&new_seq, handler);
- if (block_may_fallthru (CATCH_BODY (catch)))
+ if (gimple_seq_may_fallthru (new_seq))
{
if (!out_label)
- out_label = create_artificial_label ();
+ out_label = create_artificial_label (try_catch_loc);
- x = build1 (GOTO_EXPR, void_type_node, out_label);
- append_to_statement_list (x, &CATCH_BODY (catch));
+ x = gimple_build_goto (out_label);
+ gimple_seq_add_stmt (&new_seq, x);
}
-
- tsi_link_before (&i, CATCH_BODY (catch), TSI_SAME_STMT);
- tsi_delink (&i);
+ if (!c->type_list)
+ break;
}
- frob_into_branch_around (tp, NULL, out_label);
+ gimple_try_set_cleanup (tp, new_seq);
+
+ return frob_into_branch_around (tp, try_region, out_label);
}
-/* A subroutine of lower_eh_constructs_1. Lower a TRY_CATCH_EXPR with a
- EH_FILTER_EXPR to a sequence of labels and blocks, plus the exception
+/* A subroutine of lower_eh_constructs_1. Lower a GIMPLE_TRY with a
+ GIMPLE_EH_FILTER to a sequence of labels and blocks, plus the exception
region trees that record all the magic. */
-static void
-lower_eh_filter (struct leh_state *state, tree *tp)
+static gimple_seq
+lower_eh_filter (struct leh_state *state, gimple tp)
{
- struct leh_state this_state;
- struct eh_region *this_region;
- tree inner = expr_first (TREE_OPERAND (*tp, 1));
- tree eh_label;
-
- if (EH_FILTER_MUST_NOT_THROW (inner))
- this_region = gen_eh_region_must_not_throw (state->cur_region);
- else
- this_region = gen_eh_region_allowed (state->cur_region,
- EH_FILTER_TYPES (inner));
- this_state = *state;
- this_state.cur_region = this_region;
+ struct leh_state this_state = *state;
+ eh_region this_region = NULL;
+ gimple inner, x;
+ gimple_seq new_seq;
- lower_eh_constructs_1 (&this_state, &TREE_OPERAND (*tp, 0));
+ inner = gimple_seq_first_stmt (gimple_try_cleanup (tp));
- if (!get_eh_region_may_contain_throw (this_region))
+ if (flag_exceptions)
{
- *tp = TREE_OPERAND (*tp, 0);
- return;
+ this_region = gen_eh_region_allowed (state->cur_region,
+ gimple_eh_filter_types (inner));
+ this_state.cur_region = this_region;
}
- lower_eh_constructs_1 (state, &EH_FILTER_FAILURE (inner));
- TREE_OPERAND (*tp, 1) = EH_FILTER_FAILURE (inner);
+ lower_eh_constructs_1 (&this_state, gimple_try_eval (tp));
+
+ if (!eh_region_may_contain_throw (this_region))
+ return gimple_try_eval (tp);
+
+ new_seq = NULL;
+ this_state.cur_region = state->cur_region;
+ this_state.ehp_region = this_region;
+
+ emit_eh_dispatch (&new_seq, this_region);
+ emit_resx (&new_seq, this_region);
- eh_label = create_artificial_label ();
- set_eh_region_tree_label (this_region, eh_label);
+ this_region->u.allowed.label = create_artificial_label (UNKNOWN_LOCATION);
+ x = gimple_build_label (this_region->u.allowed.label);
+ gimple_seq_add_stmt (&new_seq, x);
- frob_into_branch_around (tp, eh_label, NULL);
+ lower_eh_constructs_1 (&this_state, gimple_eh_filter_failure (inner));
+ gimple_seq_add_seq (&new_seq, gimple_eh_filter_failure (inner));
+
+ gimple_try_set_cleanup (tp, new_seq);
+
+ return frob_into_branch_around (tp, this_region, NULL);
}
-/* Implement a cleanup expression. This is similar to try-finally,
- except that we only execute the cleanup block for exception edges. */
+/* A subroutine of lower_eh_constructs_1. Lower a GIMPLE_TRY with
+ an GIMPLE_EH_MUST_NOT_THROW to a sequence of labels and blocks,
+ plus the exception region trees that record all the magic. */
-static void
-lower_cleanup (struct leh_state *state, tree *tp)
+static gimple_seq
+lower_eh_must_not_throw (struct leh_state *state, gimple tp)
{
- struct leh_state this_state;
- struct eh_region *this_region;
- struct leh_tf_state fake_tf;
+ struct leh_state this_state = *state;
- /* If not using eh, then exception-only cleanups are no-ops. */
- if (!flag_exceptions)
+ if (flag_exceptions)
{
- *tp = TREE_OPERAND (*tp, 0);
- lower_eh_constructs_1 (state, tp);
- return;
+ gimple inner = gimple_seq_first_stmt (gimple_try_cleanup (tp));
+ eh_region this_region;
+
+ this_region = gen_eh_region_must_not_throw (state->cur_region);
+ this_region->u.must_not_throw.failure_decl
+ = gimple_eh_must_not_throw_fndecl (inner);
+ this_region->u.must_not_throw.failure_loc = gimple_location (tp);
+
+ /* In order to get mangling applied to this decl, we must mark it
+ used now. Otherwise, pass_ipa_free_lang_data won't think it
+ needs to happen. */
+ TREE_USED (this_region->u.must_not_throw.failure_decl) = 1;
+
+ this_state.cur_region = this_region;
}
- this_region = gen_eh_region_cleanup (state->cur_region, state->prev_try);
- this_state = *state;
- this_state.cur_region = this_region;
+ lower_eh_constructs_1 (&this_state, gimple_try_eval (tp));
+
+ return gimple_try_eval (tp);
+}
+
+/* Implement a cleanup expression. This is similar to try-finally,
+ except that we only execute the cleanup block for exception edges. */
- lower_eh_constructs_1 (&this_state, &TREE_OPERAND (*tp, 0));
+static gimple_seq
+lower_cleanup (struct leh_state *state, gimple tp)
+{
+ struct leh_state this_state = *state;
+ eh_region this_region = NULL;
+ struct leh_tf_state fake_tf;
+ gimple_seq result;
+ bool cleanup_dead = cleanup_is_dead_in (state->cur_region);
- if (!get_eh_region_may_contain_throw (this_region))
+ if (flag_exceptions && !cleanup_dead)
{
- *tp = TREE_OPERAND (*tp, 0);
- return;
+ this_region = gen_eh_region_cleanup (state->cur_region);
+ this_state.cur_region = this_region;
}
+ lower_eh_constructs_1 (&this_state, gimple_try_eval (tp));
+
+ if (cleanup_dead || !eh_region_may_contain_throw (this_region))
+ return gimple_try_eval (tp);
+
/* Build enough of a try-finally state so that we can reuse
honor_protect_cleanup_actions. */
memset (&fake_tf, 0, sizeof (fake_tf));
- fake_tf.top_p = tp;
+ fake_tf.top_p = fake_tf.try_finally_expr = tp;
fake_tf.outer = state;
fake_tf.region = this_region;
- fake_tf.may_fallthru = block_may_fallthru (TREE_OPERAND (*tp, 0));
+ fake_tf.may_fallthru = gimple_seq_may_fallthru (gimple_try_eval (tp));
fake_tf.may_throw = true;
- fake_tf.eh_label = create_artificial_label ();
- set_eh_region_tree_label (this_region, fake_tf.eh_label);
-
honor_protect_cleanup_actions (state, NULL, &fake_tf);
if (fake_tf.may_throw)
{
/* In this case honor_protect_cleanup_actions had nothing to do,
and we should process this normally. */
- lower_eh_constructs_1 (state, &TREE_OPERAND (*tp, 1));
- frob_into_branch_around (tp, fake_tf.eh_label, fake_tf.fallthru_label);
+ lower_eh_constructs_1 (state, gimple_try_cleanup (tp));
+ result = frob_into_branch_around (tp, this_region,
+ fake_tf.fallthru_label);
}
else
{
/* In this case honor_protect_cleanup_actions did nearly all of
the work. All we have left is to append the fallthru_label. */
- *tp = TREE_OPERAND (*tp, 0);
+ result = gimple_try_eval (tp);
if (fake_tf.fallthru_label)
{
- tree x = build1 (LABEL_EXPR, void_type_node, fake_tf.fallthru_label);
- append_to_statement_list (x, tp);
+ gimple x = gimple_build_label (fake_tf.fallthru_label);
+ gimple_seq_add_stmt (&result, x);
}
}
+ return result;
}
-/* Main loop for lowering eh constructs. */
+/* Main loop for lowering eh constructs. Also moves gsi to the next
+ statement. */
static void
-lower_eh_constructs_1 (struct leh_state *state, tree *tp)
+lower_eh_constructs_2 (struct leh_state *state, gimple_stmt_iterator *gsi)
{
- tree_stmt_iterator i;
- tree t = *tp;
+ gimple_seq replace;
+ gimple x;
+ gimple stmt = gsi_stmt (*gsi);
- switch (TREE_CODE (t))
+ switch (gimple_code (stmt))
{
- case COND_EXPR:
- lower_eh_constructs_1 (state, &COND_EXPR_THEN (t));
- lower_eh_constructs_1 (state, &COND_EXPR_ELSE (t));
- break;
+ case GIMPLE_CALL:
+ {
+ tree fndecl = gimple_call_fndecl (stmt);
+ tree rhs, lhs;
- case CALL_EXPR:
- /* Look for things that can throw exceptions, and record them. */
- if (state->cur_region && tree_could_throw_p (t))
+ if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
+ switch (DECL_FUNCTION_CODE (fndecl))
+ {
+ case BUILT_IN_EH_POINTER:
+ /* The front end may have generated a call to
+ __builtin_eh_pointer (0) within a catch region. Replace
+ this zero argument with the current catch region number. */
+ if (state->ehp_region)
+ {
+ tree nr = build_int_cst (NULL, state->ehp_region->index);
+ gimple_call_set_arg (stmt, 0, nr);
+ }
+ else
+ {
+ /* The user has dome something silly. Remove it. */
+ rhs = build_int_cst (ptr_type_node, 0);
+ goto do_replace;
+ }
+ break;
+
+ case BUILT_IN_EH_FILTER:
+ /* ??? This should never appear, but since it's a builtin it
+ is accessible to abuse by users. Just remove it and
+ replace the use with the arbitrary value zero. */
+ rhs = build_int_cst (TREE_TYPE (TREE_TYPE (fndecl)), 0);
+ do_replace:
+ lhs = gimple_call_lhs (stmt);
+ x = gimple_build_assign (lhs, rhs);
+ gsi_insert_before (gsi, x, GSI_SAME_STMT);
+ /* FALLTHRU */
+
+ case BUILT_IN_EH_COPY_VALUES:
+ /* Likewise this should not appear. Remove it. */
+ gsi_remove (gsi, true);
+ return;
+
+ default:
+ break;
+ }
+ }
+ /* FALLTHRU */
+
+ case GIMPLE_ASSIGN:
+ /* If the stmt can throw use a new temporary for the assignment
+ to a LHS. This makes sure the old value of the LHS is
+ available on the EH edge. Only do so for statements that
+ potentially fall thru (no noreturn calls e.g.), otherwise
+ this new assignment might create fake fallthru regions. */
+ if (stmt_could_throw_p (stmt)
+ && gimple_has_lhs (stmt)
+ && gimple_stmt_may_fallthru (stmt)
+ && !tree_could_throw_p (gimple_get_lhs (stmt))
+ && is_gimple_reg_type (TREE_TYPE (gimple_get_lhs (stmt))))
{
- record_stmt_eh_region (state->cur_region, t);
- note_eh_region_may_contain_throw (state->cur_region);
+ tree lhs = gimple_get_lhs (stmt);
+ tree tmp = create_tmp_var (TREE_TYPE (lhs), NULL);
+ gimple s = gimple_build_assign (lhs, tmp);
+ gimple_set_location (s, gimple_location (stmt));
+ gimple_set_block (s, gimple_block (stmt));
+ gimple_set_lhs (stmt, tmp);
+ if (TREE_CODE (TREE_TYPE (tmp)) == COMPLEX_TYPE
+ || TREE_CODE (TREE_TYPE (tmp)) == VECTOR_TYPE)
+ DECL_GIMPLE_REG_P (tmp) = 1;
+ gsi_insert_after (gsi, s, GSI_SAME_STMT);
}
- break;
-
- case MODIFY_EXPR:
/* Look for things that can throw exceptions, and record them. */
- if (state->cur_region && tree_could_throw_p (t))
+ if (state->cur_region && stmt_could_throw_p (stmt))
{
- record_stmt_eh_region (state->cur_region, t);
+ record_stmt_eh_region (state->cur_region, stmt);
note_eh_region_may_contain_throw (state->cur_region);
}
break;
- case GOTO_EXPR:
- case RETURN_EXPR:
- maybe_record_in_goto_queue (state, t);
- break;
- case SWITCH_EXPR:
- verify_norecord_switch_expr (state, t);
- break;
-
- case TRY_FINALLY_EXPR:
- lower_try_finally (state, tp);
+ case GIMPLE_COND:
+ case GIMPLE_GOTO:
+ case GIMPLE_RETURN:
+ maybe_record_in_goto_queue (state, stmt);
break;
- case TRY_CATCH_EXPR:
- i = tsi_start (TREE_OPERAND (t, 1));
- switch (TREE_CODE (tsi_stmt (i)))
- {
- case CATCH_EXPR:
- lower_catch (state, tp);
- break;
- case EH_FILTER_EXPR:
- lower_eh_filter (state, tp);
- break;
- default:
- lower_cleanup (state, tp);
- break;
- }
+ case GIMPLE_SWITCH:
+ verify_norecord_switch_expr (state, stmt);
break;
- case STATEMENT_LIST:
- for (i = tsi_start (t); !tsi_end_p (i); )
+ case GIMPLE_TRY:
+ if (gimple_try_kind (stmt) == GIMPLE_TRY_FINALLY)
+ replace = lower_try_finally (state, stmt);
+ else
{
- lower_eh_constructs_1 (state, tsi_stmt_ptr (i));
- t = tsi_stmt (i);
- if (TREE_CODE (t) == STATEMENT_LIST)
+ x = gimple_seq_first_stmt (gimple_try_cleanup (stmt));
+ if (!x)
{
- tsi_link_before (&i, t, TSI_SAME_STMT);
- tsi_delink (&i);
+ replace = gimple_try_eval (stmt);
+ lower_eh_constructs_1 (state, replace);
}
else
- tsi_next (&i);
+ switch (gimple_code (x))
+ {
+ case GIMPLE_CATCH:
+ replace = lower_catch (state, stmt);
+ break;
+ case GIMPLE_EH_FILTER:
+ replace = lower_eh_filter (state, stmt);
+ break;
+ case GIMPLE_EH_MUST_NOT_THROW:
+ replace = lower_eh_must_not_throw (state, stmt);
+ break;
+ default:
+ replace = lower_cleanup (state, stmt);
+ break;
+ }
}
- break;
+
+ /* Remove the old stmt and insert the transformed sequence
+ instead. */
+ gsi_insert_seq_before (gsi, replace, GSI_SAME_STMT);
+ gsi_remove (gsi, true);
+
+ /* Return since we don't want gsi_next () */
+ return;
default:
/* A type, a decl, or some kind of statement that we're not
interested in. Don't walk them. */
break;
}
+
+ gsi_next (gsi);
}
+/* A helper to unwrap a gimple_seq and feed stmts to lower_eh_constructs_2. */
+
static void
+lower_eh_constructs_1 (struct leh_state *state, gimple_seq seq)
+{
+ gimple_stmt_iterator gsi;
+ for (gsi = gsi_start (seq); !gsi_end_p (gsi);)
+ lower_eh_constructs_2 (state, &gsi);
+}
+
+static unsigned int
lower_eh_constructs (void)
{
struct leh_state null_state;
- tree *tp = &DECL_SAVED_TREE (current_function_decl);
+ gimple_seq bodyp;
+
+ bodyp = gimple_body (current_function_decl);
+ if (bodyp == NULL)
+ return 0;
finally_tree = htab_create (31, struct_ptr_hash, struct_ptr_eq, free);
+ eh_region_may_contain_throw_map = BITMAP_ALLOC (NULL);
+ memset (&null_state, 0, sizeof (null_state));
- collect_finally_tree (*tp, NULL);
+ collect_finally_tree_1 (bodyp, NULL);
+ lower_eh_constructs_1 (&null_state, bodyp);
- memset (&null_state, 0, sizeof (null_state));
- lower_eh_constructs_1 (&null_state, tp);
+ /* We assume there's a return statement, or something, at the end of
+ the function, and thus ploping the EH sequence afterward won't
+ change anything. */
+ gcc_assert (!gimple_seq_may_fallthru (bodyp));
+ gimple_seq_add_seq (&bodyp, eh_seq);
+
+ /* We assume that since BODYP already existed, adding EH_SEQ to it
+ didn't change its value, and we don't have to re-set the function. */
+ gcc_assert (bodyp == gimple_body (current_function_decl));
htab_delete (finally_tree);
+ BITMAP_FREE (eh_region_may_contain_throw_map);
+ eh_seq = NULL;
- collect_eh_region_array ();
+ /* If this function needs a language specific EH personality routine
+ and the frontend didn't already set one do so now. */
+ if (function_needs_eh_personality (cfun) == eh_personality_lang
+ && !DECL_FUNCTION_PERSONALITY (current_function_decl))
+ DECL_FUNCTION_PERSONALITY (current_function_decl)
+ = lang_hooks.eh_personality ();
+
+ return 0;
}
-struct tree_opt_pass pass_lower_eh =
+struct gimple_opt_pass pass_lower_eh =
{
+ {
+ GIMPLE_PASS,
"eh", /* name */
NULL, /* gate */
lower_eh_constructs, /* execute */
TV_TREE_EH, /* tv_id */
PROP_gimple_lcf, /* properties_required */
PROP_gimple_leh, /* properties_provided */
- PROP_gimple_lcf, /* properties_destroyed */
+ 0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_dump_func, /* todo_flags_finish */
- 0 /* letter */
+ TODO_dump_func /* todo_flags_finish */
+ }
};
-
\f
-/* Construct EH edges for STMT. */
+/* Create the multiple edges from an EH_DISPATCH statement to all of
+ the possible handlers for its EH region. Return true if there's
+ no fallthru edge; false if there is. */
-static void
-make_eh_edge (struct eh_region *region, void *data)
+bool
+make_eh_dispatch_edges (gimple stmt)
{
- tree stmt, lab;
+ eh_region r;
+ eh_catch c;
basic_block src, dst;
- stmt = data;
- lab = get_eh_region_tree_label (region);
+ r = get_eh_region_from_number (gimple_eh_dispatch_region (stmt));
+ src = gimple_bb (stmt);
+
+ switch (r->type)
+ {
+ case ERT_TRY:
+ for (c = r->u.eh_try.first_catch; c ; c = c->next_catch)
+ {
+ dst = label_to_block (c->label);
+ make_edge (src, dst, 0);
+
+ /* A catch-all handler doesn't have a fallthru. */
+ if (c->type_list == NULL)
+ return false;
+ }
+ break;
+
+ case ERT_ALLOWED_EXCEPTIONS:
+ dst = label_to_block (r->u.allowed.label);
+ make_edge (src, dst, 0);
+ break;
- src = bb_for_stmt (stmt);
- dst = label_to_block (lab);
+ default:
+ gcc_unreachable ();
+ }
- make_edge (src, dst, EDGE_ABNORMAL | EDGE_EH);
+ return true;
}
+/* Create the single EH edge from STMT to its nearest landing pad,
+ if there is such a landing pad within the current function. */
+
void
-make_eh_edges (tree stmt)
+make_eh_edges (gimple stmt)
{
- int region_nr;
- bool is_resx;
+ basic_block src, dst;
+ eh_landing_pad lp;
+ int lp_nr;
- if (TREE_CODE (stmt) == RESX_EXPR)
- {
- region_nr = TREE_INT_CST_LOW (TREE_OPERAND (stmt, 0));
- is_resx = true;
- }
- else
- {
- region_nr = lookup_stmt_eh_region (stmt);
- if (region_nr < 0)
- return;
- is_resx = false;
- }
+ lp_nr = lookup_stmt_eh_lp (stmt);
+ if (lp_nr <= 0)
+ return;
- foreach_reachable_handler (region_nr, is_resx, make_eh_edge, stmt);
+ lp = get_eh_landing_pad_from_number (lp_nr);
+ gcc_assert (lp != NULL);
+
+ src = gimple_bb (stmt);
+ dst = label_to_block (lp->post_landing_pad);
+ make_edge (src, dst, EDGE_EH);
}
-static bool mark_eh_edge_found_error;
+/* Do the work in redirecting EDGE_IN to NEW_BB within the EH region tree;
+ do not actually perform the final edge redirection.
+
+ CHANGE_REGION is true when we're being called from cleanup_empty_eh and
+ we intend to change the destination EH region as well; this means
+ EH_LANDING_PAD_NR must already be set on the destination block label.
+ If false, we're being called from generic cfg manipulation code and we
+ should preserve our place within the region tree. */
-/* Mark edge make_eh_edge would create for given region by setting it aux
- field, output error if something goes wrong. */
static void
-mark_eh_edge (struct eh_region *region, void *data)
+redirect_eh_edge_1 (edge edge_in, basic_block new_bb, bool change_region)
{
- tree stmt, lab;
- basic_block src, dst;
+ eh_landing_pad old_lp, new_lp;
+ basic_block old_bb;
+ gimple throw_stmt;
+ int old_lp_nr, new_lp_nr;
+ tree old_label, new_label;
+ edge_iterator ei;
edge e;
- stmt = data;
- lab = get_eh_region_tree_label (region);
+ old_bb = edge_in->dest;
+ old_label = gimple_block_label (old_bb);
+ old_lp_nr = EH_LANDING_PAD_NR (old_label);
+ gcc_assert (old_lp_nr > 0);
+ old_lp = get_eh_landing_pad_from_number (old_lp_nr);
- src = bb_for_stmt (stmt);
- dst = label_to_block (lab);
+ throw_stmt = last_stmt (edge_in->src);
+ gcc_assert (lookup_stmt_eh_lp (throw_stmt) == old_lp_nr);
- e = find_edge (src, dst);
- if (!e)
- {
- error ("EH edge %i->%i is missing %i %i.", src->index, dst->index, src, dst);
- mark_eh_edge_found_error = true;
- }
- else if (!(e->flags & EDGE_EH))
+ new_label = gimple_block_label (new_bb);
+
+ /* Look for an existing region that might be using NEW_BB already. */
+ new_lp_nr = EH_LANDING_PAD_NR (new_label);
+ if (new_lp_nr)
{
- error ("EH edge %i->%i miss EH flag.", src->index, dst->index);
- mark_eh_edge_found_error = true;
+ new_lp = get_eh_landing_pad_from_number (new_lp_nr);
+ gcc_assert (new_lp);
+
+ /* Unless CHANGE_REGION is true, the new and old landing pad
+ had better be associated with the same EH region. */
+ gcc_assert (change_region || new_lp->region == old_lp->region);
}
- else if (e->aux)
+ else
{
- /* ??? might not be mistake. */
- error ("EH edge %i->%i has duplicated regions.", src->index, dst->index);
- mark_eh_edge_found_error = true;
+ new_lp = NULL;
+ gcc_assert (!change_region);
}
- else
- e->aux = (void *)1;
-}
-/* Verify that BB containing stmt as last stmt has precisely the edges
- make_eh_edges would create. */
-bool
-verify_eh_edges (tree stmt)
-{
- int region_nr;
- bool is_resx;
- basic_block bb = bb_for_stmt (stmt);
- edge_iterator ei;
- edge e;
+ /* Notice when we redirect the last EH edge away from OLD_BB. */
+ FOR_EACH_EDGE (e, ei, old_bb->preds)
+ if (e != edge_in && (e->flags & EDGE_EH))
+ break;
- FOR_EACH_EDGE (e, ei, bb->succs)
- gcc_assert (!e->aux);
- mark_eh_edge_found_error = false;
- if (TREE_CODE (stmt) == RESX_EXPR)
+ if (new_lp)
{
- region_nr = TREE_INT_CST_LOW (TREE_OPERAND (stmt, 0));
- is_resx = true;
+ /* NEW_LP already exists. If there are still edges into OLD_LP,
+ there's nothing to do with the EH tree. If there are no more
+ edges into OLD_LP, then we want to remove OLD_LP as it is unused.
+ If CHANGE_REGION is true, then our caller is expecting to remove
+ the landing pad. */
+ if (e == NULL && !change_region)
+ remove_eh_landing_pad (old_lp);
}
else
{
- region_nr = lookup_stmt_eh_region (stmt);
- if (region_nr < 0)
- {
- FOR_EACH_EDGE (e, ei, bb->succs)
- if (e->flags & EDGE_EH)
- {
- error ("BB %i can not throw but has EH edges", bb->index);
- return true;
- }
- return false;
- }
- if (!tree_could_throw_p (stmt))
+ /* No correct landing pad exists. If there are no more edges
+ into OLD_LP, then we can simply re-use the existing landing pad.
+ Otherwise, we have to create a new landing pad. */
+ if (e == NULL)
{
- error ("BB %i last statement has incorrectly set region", bb->index);
- return true;
+ EH_LANDING_PAD_NR (old_lp->post_landing_pad) = 0;
+ new_lp = old_lp;
}
- is_resx = false;
+ else
+ new_lp = gen_eh_landing_pad (old_lp->region);
+ new_lp->post_landing_pad = new_label;
+ EH_LANDING_PAD_NR (new_label) = new_lp->index;
}
- foreach_reachable_handler (region_nr, is_resx, mark_eh_edge, stmt);
- FOR_EACH_EDGE (e, ei, bb->succs)
+ /* Maybe move the throwing statement to the new region. */
+ if (old_lp != new_lp)
{
- if ((e->flags & EDGE_EH) && !e->aux)
- {
- error ("Unnecessary EH edge %i->%i", bb->index, e->dest->index);
- mark_eh_edge_found_error = true;
- return true;
- }
- e->aux = NULL;
+ remove_stmt_from_eh_lp (throw_stmt);
+ add_stmt_to_eh_lp (throw_stmt, new_lp->index);
}
- return mark_eh_edge_found_error;
}
-\f
-/* Return true if the expr can trap, as in dereferencing an invalid pointer
- location or floating point arithmetic. C.f. the rtl version, may_trap_p.
- This routine expects only GIMPLE lhs or rhs input. */
+/* Redirect EH edge E to NEW_BB. */
-bool
-tree_could_trap_p (tree expr)
+edge
+redirect_eh_edge (edge edge_in, basic_block new_bb)
{
- enum tree_code code = TREE_CODE (expr);
- bool honor_nans = false;
- bool honor_snans = false;
- bool fp_operation = false;
- bool honor_trapv = false;
- tree t, base;
+ redirect_eh_edge_1 (edge_in, new_bb, false);
+ return ssa_redirect_edge (edge_in, new_bb);
+}
- if (TREE_CODE_CLASS (code) == tcc_comparison
- || TREE_CODE_CLASS (code) == tcc_unary
- || TREE_CODE_CLASS (code) == tcc_binary)
+/* This is a subroutine of gimple_redirect_edge_and_branch. Update the
+ labels for redirecting a non-fallthru EH_DISPATCH edge E to NEW_BB.
+ The actual edge update will happen in the caller. */
+
+void
+redirect_eh_dispatch_edge (gimple stmt, edge e, basic_block new_bb)
+{
+ tree new_lab = gimple_block_label (new_bb);
+ bool any_changed = false;
+ basic_block old_bb;
+ eh_region r;
+ eh_catch c;
+
+ r = get_eh_region_from_number (gimple_eh_dispatch_region (stmt));
+ switch (r->type)
{
- t = TREE_TYPE (expr);
- fp_operation = FLOAT_TYPE_P (t);
- if (fp_operation)
+ case ERT_TRY:
+ for (c = r->u.eh_try.first_catch; c ; c = c->next_catch)
{
- honor_nans = flag_trapping_math && !flag_finite_math_only;
- honor_snans = flag_signaling_nans != 0;
+ old_bb = label_to_block (c->label);
+ if (old_bb == e->dest)
+ {
+ c->label = new_lab;
+ any_changed = true;
+ }
}
- else if (INTEGRAL_TYPE_P (t) && TYPE_TRAP_SIGNED (t))
- honor_trapv = true;
- }
-
- restart:
- switch (code)
- {
- case TARGET_MEM_REF:
- /* For TARGET_MEM_REFs use the information based on the original
- reference. */
- expr = TMR_ORIGINAL (expr);
- code = TREE_CODE (expr);
- goto restart;
-
- case COMPONENT_REF:
- case REALPART_EXPR:
- case IMAGPART_EXPR:
- case BIT_FIELD_REF:
- case WITH_SIZE_EXPR:
- expr = TREE_OPERAND (expr, 0);
- code = TREE_CODE (expr);
- goto restart;
-
- case ARRAY_RANGE_REF:
- /* Let us be conservative here for now. We might be checking bounds of
- the access similarly to the case below. */
- if (!TREE_THIS_NOTRAP (expr))
- return true;
-
- base = TREE_OPERAND (expr, 0);
- return tree_could_trap_p (base);
-
- case ARRAY_REF:
- base = TREE_OPERAND (expr, 0);
- if (tree_could_trap_p (base))
- return true;
-
- if (TREE_THIS_NOTRAP (expr))
- return false;
+ break;
- return !in_array_bounds_p (expr);
+ case ERT_ALLOWED_EXCEPTIONS:
+ old_bb = label_to_block (r->u.allowed.label);
+ gcc_assert (old_bb == e->dest);
+ r->u.allowed.label = new_lab;
+ any_changed = true;
+ break;
- case INDIRECT_REF:
- case ALIGN_INDIRECT_REF:
- case MISALIGNED_INDIRECT_REF:
- return !TREE_THIS_NOTRAP (expr);
+ default:
+ gcc_unreachable ();
+ }
- case ASM_EXPR:
- return TREE_THIS_VOLATILE (expr);
+ gcc_assert (any_changed);
+}
+\f
+/* Helper function for operation_could_trap_p and stmt_could_throw_p. */
+bool
+operation_could_trap_helper_p (enum tree_code op,
+ bool fp_operation,
+ bool honor_trapv,
+ bool honor_nans,
+ bool honor_snans,
+ tree divisor,
+ bool *handled)
+{
+ *handled = true;
+ switch (op)
+ {
case TRUNC_DIV_EXPR:
case CEIL_DIV_EXPR:
case FLOOR_DIV_EXPR:
return true;
if (fp_operation)
return flag_trapping_math;
- t = TREE_OPERAND (expr, 1);
- if (!TREE_CONSTANT (t) || integer_zerop (t))
+ if (!TREE_CONSTANT (divisor) || integer_zerop (divisor))
return true;
return false;
case CONVERT_EXPR:
case FIX_TRUNC_EXPR:
- case FIX_CEIL_EXPR:
- case FIX_FLOOR_EXPR:
- case FIX_ROUND_EXPR:
/* Conversion of floating point might trap. */
return honor_nans;
return true;
return false;
+ default:
+ /* Any floating arithmetic may trap. */
+ if (fp_operation && flag_trapping_math)
+ return true;
+
+ *handled = false;
+ return false;
+ }
+}
+
+/* Return true if operation OP may trap. FP_OPERATION is true if OP is applied
+ on floating-point values. HONOR_TRAPV is true if OP is applied on integer
+ type operands that may trap. If OP is a division operator, DIVISOR contains
+ the value of the divisor. */
+
+bool
+operation_could_trap_p (enum tree_code op, bool fp_operation, bool honor_trapv,
+ tree divisor)
+{
+ bool honor_nans = (fp_operation && flag_trapping_math
+ && !flag_finite_math_only);
+ bool honor_snans = fp_operation && flag_signaling_nans != 0;
+ bool handled;
+
+ if (TREE_CODE_CLASS (op) != tcc_comparison
+ && TREE_CODE_CLASS (op) != tcc_unary
+ && TREE_CODE_CLASS (op) != tcc_binary)
+ return false;
+
+ return operation_could_trap_helper_p (op, fp_operation, honor_trapv,
+ honor_nans, honor_snans, divisor,
+ &handled);
+}
+
+/* Return true if EXPR can trap, as in dereferencing an invalid pointer
+ location or floating point arithmetic. C.f. the rtl version, may_trap_p.
+ This routine expects only GIMPLE lhs or rhs input. */
+
+bool
+tree_could_trap_p (tree expr)
+{
+ enum tree_code code;
+ bool fp_operation = false;
+ bool honor_trapv = false;
+ tree t, base, div = NULL_TREE;
+
+ if (!expr)
+ return false;
+
+ code = TREE_CODE (expr);
+ t = TREE_TYPE (expr);
+
+ if (t)
+ {
+ if (COMPARISON_CLASS_P (expr))
+ fp_operation = FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 0)));
+ else
+ fp_operation = FLOAT_TYPE_P (t);
+ honor_trapv = INTEGRAL_TYPE_P (t) && TYPE_OVERFLOW_TRAPS (t);
+ }
+
+ if (TREE_CODE_CLASS (code) == tcc_binary)
+ div = TREE_OPERAND (expr, 1);
+ if (operation_could_trap_p (code, fp_operation, honor_trapv, div))
+ return true;
+
+ restart:
+ switch (code)
+ {
+ case TARGET_MEM_REF:
+ /* For TARGET_MEM_REFs use the information based on the original
+ reference. */
+ expr = TMR_ORIGINAL (expr);
+ code = TREE_CODE (expr);
+ goto restart;
+
+ case COMPONENT_REF:
+ case REALPART_EXPR:
+ case IMAGPART_EXPR:
+ case BIT_FIELD_REF:
+ case VIEW_CONVERT_EXPR:
+ case WITH_SIZE_EXPR:
+ expr = TREE_OPERAND (expr, 0);
+ code = TREE_CODE (expr);
+ goto restart;
+
+ case ARRAY_RANGE_REF:
+ base = TREE_OPERAND (expr, 0);
+ if (tree_could_trap_p (base))
+ return true;
+ if (TREE_THIS_NOTRAP (expr))
+ return false;
+ return !range_in_array_bounds_p (expr);
+
+ case ARRAY_REF:
+ base = TREE_OPERAND (expr, 0);
+ if (tree_could_trap_p (base))
+ return true;
+ if (TREE_THIS_NOTRAP (expr))
+ return false;
+ return !in_array_bounds_p (expr);
+
+ case INDIRECT_REF:
+ case ALIGN_INDIRECT_REF:
+ case MISALIGNED_INDIRECT_REF:
+ return !TREE_THIS_NOTRAP (expr);
+
+ case ASM_EXPR:
+ return TREE_THIS_VOLATILE (expr);
+
case CALL_EXPR:
t = get_callee_fndecl (expr);
/* Assume that calls to weak functions may trap. */
return false;
default:
- /* Any floating arithmetic may trap. */
- if (fp_operation && flag_trapping_math)
- return true;
return false;
}
}
+
+/* Helper for stmt_could_throw_p. Return true if STMT (assumed to be a
+ an assignment or a conditional) may throw. */
+
+static bool
+stmt_could_throw_1_p (gimple stmt)
+{
+ enum tree_code code = gimple_expr_code (stmt);
+ bool honor_nans = false;
+ bool honor_snans = false;
+ bool fp_operation = false;
+ bool honor_trapv = false;
+ tree t;
+ size_t i;
+ bool handled, ret;
+
+ if (TREE_CODE_CLASS (code) == tcc_comparison
+ || TREE_CODE_CLASS (code) == tcc_unary
+ || TREE_CODE_CLASS (code) == tcc_binary)
+ {
+ t = gimple_expr_type (stmt);
+ fp_operation = FLOAT_TYPE_P (t);
+ if (fp_operation)
+ {
+ honor_nans = flag_trapping_math && !flag_finite_math_only;
+ honor_snans = flag_signaling_nans != 0;
+ }
+ else if (INTEGRAL_TYPE_P (t) && TYPE_OVERFLOW_TRAPS (t))
+ honor_trapv = true;
+ }
+
+ /* Check if the main expression may trap. */
+ t = is_gimple_assign (stmt) ? gimple_assign_rhs2 (stmt) : NULL;
+ ret = operation_could_trap_helper_p (code, fp_operation, honor_trapv,
+ honor_nans, honor_snans, t,
+ &handled);
+ if (handled)
+ return ret;
+
+ /* If the expression does not trap, see if any of the individual operands may
+ trap. */
+ for (i = 0; i < gimple_num_ops (stmt); i++)
+ if (tree_could_trap_p (gimple_op (stmt, i)))
+ return true;
+
+ return false;
+}
+
+
+/* Return true if statement STMT could throw an exception. */
+
+bool
+stmt_could_throw_p (gimple stmt)
+{
+ if (!flag_exceptions)
+ return false;
+
+ /* The only statements that can throw an exception are assignments,
+ conditionals, calls, resx, and asms. */
+ switch (gimple_code (stmt))
+ {
+ case GIMPLE_RESX:
+ return true;
+
+ case GIMPLE_CALL:
+ return !gimple_call_nothrow_p (stmt);
+
+ case GIMPLE_ASSIGN:
+ case GIMPLE_COND:
+ if (!flag_non_call_exceptions)
+ return false;
+ return stmt_could_throw_1_p (stmt);
+
+ case GIMPLE_ASM:
+ if (!flag_non_call_exceptions)
+ return false;
+ return gimple_asm_volatile_p (stmt);
+
+ default:
+ return false;
+ }
+}
+
+
+/* Return true if expression T could throw an exception. */
+
bool
tree_could_throw_p (tree t)
{
if (TREE_CODE (t) == MODIFY_EXPR)
{
if (flag_non_call_exceptions
- && tree_could_trap_p (TREE_OPERAND (t, 0)))
- return true;
+ && tree_could_trap_p (TREE_OPERAND (t, 0)))
+ return true;
t = TREE_OPERAND (t, 1);
}
return false;
}
+/* Return true if STMT can throw an exception that is not caught within
+ the current function (CFUN). */
+
+bool
+stmt_can_throw_external (gimple stmt)
+{
+ int lp_nr;
+
+ if (!stmt_could_throw_p (stmt))
+ return false;
+
+ lp_nr = lookup_stmt_eh_lp (stmt);
+ return lp_nr == 0;
+}
+
+/* Return true if STMT can throw an exception that is caught within
+ the current function (CFUN). */
+
bool
-tree_can_throw_internal (tree stmt)
+stmt_can_throw_internal (gimple stmt)
{
- int region_nr;
- bool is_resx = false;
+ int lp_nr;
- if (TREE_CODE (stmt) == RESX_EXPR)
- region_nr = TREE_INT_CST_LOW (TREE_OPERAND (stmt, 0)), is_resx = true;
- else
- region_nr = lookup_stmt_eh_region (stmt);
- if (region_nr < 0)
+ if (!stmt_could_throw_p (stmt))
return false;
- return can_throw_internal_1 (region_nr, is_resx);
+
+ lp_nr = lookup_stmt_eh_lp (stmt);
+ return lp_nr > 0;
}
+/* Given a statement STMT in IFUN, if STMT can no longer throw, then
+ remove any entry it might have from the EH table. Return true if
+ any change was made. */
+
bool
-tree_can_throw_external (tree stmt)
+maybe_clean_eh_stmt_fn (struct function *ifun, gimple stmt)
{
- int region_nr;
- bool is_resx = false;
+ if (stmt_could_throw_p (stmt))
+ return false;
+ return remove_stmt_from_eh_lp_fn (ifun, stmt);
+}
- if (TREE_CODE (stmt) == RESX_EXPR)
- region_nr = TREE_INT_CST_LOW (TREE_OPERAND (stmt, 0)), is_resx = true;
- else
- region_nr = lookup_stmt_eh_region (stmt);
- if (region_nr < 0)
- return tree_could_throw_p (stmt);
- else
- return can_throw_external_1 (region_nr, is_resx);
+/* Likewise, but always use the current function. */
+
+bool
+maybe_clean_eh_stmt (gimple stmt)
+{
+ return maybe_clean_eh_stmt_fn (cfun, stmt);
}
/* Given a statement OLD_STMT and a new statement NEW_STMT that has replaced
in the table if it should be in there. Return TRUE if a replacement was
done that my require an EH edge purge. */
-bool
-maybe_clean_or_replace_eh_stmt (tree old_stmt, tree new_stmt)
+bool
+maybe_clean_or_replace_eh_stmt (gimple old_stmt, gimple new_stmt)
{
- int region_nr = lookup_stmt_eh_region (old_stmt);
+ int lp_nr = lookup_stmt_eh_lp (old_stmt);
- if (region_nr >= 0)
+ if (lp_nr != 0)
{
- bool new_stmt_could_throw = tree_could_throw_p (new_stmt);
+ bool new_stmt_could_throw = stmt_could_throw_p (new_stmt);
if (new_stmt == old_stmt && new_stmt_could_throw)
return false;
- remove_stmt_from_eh_region (old_stmt);
+ remove_stmt_from_eh_lp (old_stmt);
if (new_stmt_could_throw)
{
- add_stmt_to_eh_region (new_stmt, region_nr);
+ add_stmt_to_eh_lp (new_stmt, lp_nr);
return false;
}
else
return false;
}
+
+/* Given a statement OLD_STMT in OLD_FUN and a duplicate statment NEW_STMT
+ in NEW_FUN, copy the EH table data from OLD_STMT to NEW_STMT. The MAP
+ operand is the return value of duplicate_eh_regions. */
+
+bool
+maybe_duplicate_eh_stmt_fn (struct function *new_fun, gimple new_stmt,
+ struct function *old_fun, gimple old_stmt,
+ struct pointer_map_t *map, int default_lp_nr)
+{
+ int old_lp_nr, new_lp_nr;
+ void **slot;
+
+ if (!stmt_could_throw_p (new_stmt))
+ return false;
+
+ old_lp_nr = lookup_stmt_eh_lp_fn (old_fun, old_stmt);
+ if (old_lp_nr == 0)
+ {
+ if (default_lp_nr == 0)
+ return false;
+ new_lp_nr = default_lp_nr;
+ }
+ else if (old_lp_nr > 0)
+ {
+ eh_landing_pad old_lp, new_lp;
+
+ old_lp = VEC_index (eh_landing_pad, old_fun->eh->lp_array, old_lp_nr);
+ slot = pointer_map_contains (map, old_lp);
+ new_lp = (eh_landing_pad) *slot;
+ new_lp_nr = new_lp->index;
+ }
+ else
+ {
+ eh_region old_r, new_r;
+
+ old_r = VEC_index (eh_region, old_fun->eh->region_array, -old_lp_nr);
+ slot = pointer_map_contains (map, old_r);
+ new_r = (eh_region) *slot;
+ new_lp_nr = -new_r->index;
+ }
+
+ add_stmt_to_eh_lp_fn (new_fun, new_stmt, new_lp_nr);
+ return true;
+}
+
+/* Similar, but both OLD_STMT and NEW_STMT are within the current function,
+ and thus no remapping is required. */
+
+bool
+maybe_duplicate_eh_stmt (gimple new_stmt, gimple old_stmt)
+{
+ int lp_nr;
+
+ if (!stmt_could_throw_p (new_stmt))
+ return false;
+
+ lp_nr = lookup_stmt_eh_lp (old_stmt);
+ if (lp_nr == 0)
+ return false;
+
+ add_stmt_to_eh_lp (new_stmt, lp_nr);
+ return true;
+}
+\f
+/* Returns TRUE if oneh and twoh are exception handlers (gimple_try_cleanup of
+ GIMPLE_TRY) that are similar enough to be considered the same. Currently
+ this only handles handlers consisting of a single call, as that's the
+ important case for C++: a destructor call for a particular object showing
+ up in multiple handlers. */
+
+static bool
+same_handler_p (gimple_seq oneh, gimple_seq twoh)
+{
+ gimple_stmt_iterator gsi;
+ gimple ones, twos;
+ unsigned int ai;
+
+ gsi = gsi_start (oneh);
+ if (!gsi_one_before_end_p (gsi))
+ return false;
+ ones = gsi_stmt (gsi);
+
+ gsi = gsi_start (twoh);
+ if (!gsi_one_before_end_p (gsi))
+ return false;
+ twos = gsi_stmt (gsi);
+
+ if (!is_gimple_call (ones)
+ || !is_gimple_call (twos)
+ || gimple_call_lhs (ones)
+ || gimple_call_lhs (twos)
+ || gimple_call_chain (ones)
+ || gimple_call_chain (twos)
+ || !operand_equal_p (gimple_call_fn (ones), gimple_call_fn (twos), 0)
+ || gimple_call_num_args (ones) != gimple_call_num_args (twos))
+ return false;
+
+ for (ai = 0; ai < gimple_call_num_args (ones); ++ai)
+ if (!operand_equal_p (gimple_call_arg (ones, ai),
+ gimple_call_arg (twos, ai), 0))
+ return false;
+
+ return true;
+}
+
+/* Optimize
+ try { A() } finally { try { ~B() } catch { ~A() } }
+ try { ... } finally { ~A() }
+ into
+ try { A() } catch { ~B() }
+ try { ~B() ... } finally { ~A() }
+
+ This occurs frequently in C++, where A is a local variable and B is a
+ temporary used in the initializer for A. */
+
+static void
+optimize_double_finally (gimple one, gimple two)
+{
+ gimple oneh;
+ gimple_stmt_iterator gsi;
+
+ gsi = gsi_start (gimple_try_cleanup (one));
+ if (!gsi_one_before_end_p (gsi))
+ return;
+
+ oneh = gsi_stmt (gsi);
+ if (gimple_code (oneh) != GIMPLE_TRY
+ || gimple_try_kind (oneh) != GIMPLE_TRY_CATCH)
+ return;
+
+ if (same_handler_p (gimple_try_cleanup (oneh), gimple_try_cleanup (two)))
+ {
+ gimple_seq seq = gimple_try_eval (oneh);
+
+ gimple_try_set_cleanup (one, seq);
+ gimple_try_set_kind (one, GIMPLE_TRY_CATCH);
+ seq = copy_gimple_seq_and_replace_locals (seq);
+ gimple_seq_add_seq (&seq, gimple_try_eval (two));
+ gimple_try_set_eval (two, seq);
+ }
+}
+
+/* Perform EH refactoring optimizations that are simpler to do when code
+ flow has been lowered but EH structures haven't. */
+
+static void
+refactor_eh_r (gimple_seq seq)
+{
+ gimple_stmt_iterator gsi;
+ gimple one, two;
+
+ one = NULL;
+ two = NULL;
+ gsi = gsi_start (seq);
+ while (1)
+ {
+ one = two;
+ if (gsi_end_p (gsi))
+ two = NULL;
+ else
+ two = gsi_stmt (gsi);
+ if (one
+ && two
+ && gimple_code (one) == GIMPLE_TRY
+ && gimple_code (two) == GIMPLE_TRY
+ && gimple_try_kind (one) == GIMPLE_TRY_FINALLY
+ && gimple_try_kind (two) == GIMPLE_TRY_FINALLY)
+ optimize_double_finally (one, two);
+ if (one)
+ switch (gimple_code (one))
+ {
+ case GIMPLE_TRY:
+ refactor_eh_r (gimple_try_eval (one));
+ refactor_eh_r (gimple_try_cleanup (one));
+ break;
+ case GIMPLE_CATCH:
+ refactor_eh_r (gimple_catch_handler (one));
+ break;
+ case GIMPLE_EH_FILTER:
+ refactor_eh_r (gimple_eh_filter_failure (one));
+ break;
+ default:
+ break;
+ }
+ if (two)
+ gsi_next (&gsi);
+ else
+ break;
+ }
+}
+
+static unsigned
+refactor_eh (void)
+{
+ refactor_eh_r (gimple_body (current_function_decl));
+ return 0;
+}
+
+static bool
+gate_refactor_eh (void)
+{
+ return flag_exceptions != 0;
+}
+
+struct gimple_opt_pass pass_refactor_eh =
+{
+ {
+ GIMPLE_PASS,
+ "ehopt", /* name */
+ gate_refactor_eh, /* gate */
+ refactor_eh, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_TREE_EH, /* tv_id */
+ PROP_gimple_lcf, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func /* todo_flags_finish */
+ }
+};
+\f
+/* At the end of gimple optimization, we can lower RESX. */
+
+static bool
+lower_resx (basic_block bb, gimple stmt, struct pointer_map_t *mnt_map)
+{
+ int lp_nr;
+ eh_region src_r, dst_r;
+ gimple_stmt_iterator gsi;
+ gimple x;
+ tree fn, src_nr;
+ bool ret = false;
+
+ lp_nr = lookup_stmt_eh_lp (stmt);
+ if (lp_nr != 0)
+ dst_r = get_eh_region_from_lp_number (lp_nr);
+ else
+ dst_r = NULL;
+
+ src_r = get_eh_region_from_number (gimple_resx_region (stmt));
+ gsi = gsi_last_bb (bb);
+
+ if (src_r == NULL)
+ {
+ /* We can wind up with no source region when pass_cleanup_eh shows
+ that there are no entries into an eh region and deletes it, but
+ then the block that contains the resx isn't removed. This can
+ happen without optimization when the switch statement created by
+ lower_try_finally_switch isn't simplified to remove the eh case.
+
+ Resolve this by expanding the resx node to an abort. */
+
+ fn = implicit_built_in_decls[BUILT_IN_TRAP];
+ x = gimple_build_call (fn, 0);
+ gsi_insert_before (&gsi, x, GSI_SAME_STMT);
+
+ while (EDGE_COUNT (bb->succs) > 0)
+ remove_edge (EDGE_SUCC (bb, 0));
+ }
+ else if (dst_r)
+ {
+ /* When we have a destination region, we resolve this by copying
+ the excptr and filter values into place, and changing the edge
+ to immediately after the landing pad. */
+ edge e;
+
+ if (lp_nr < 0)
+ {
+ basic_block new_bb;
+ void **slot;
+ tree lab;
+
+ /* We are resuming into a MUST_NOT_CALL region. Expand a call to
+ the failure decl into a new block, if needed. */
+ gcc_assert (dst_r->type == ERT_MUST_NOT_THROW);
+
+ slot = pointer_map_contains (mnt_map, dst_r);
+ if (slot == NULL)
+ {
+ gimple_stmt_iterator gsi2;
+
+ new_bb = create_empty_bb (bb);
+ lab = gimple_block_label (new_bb);
+ gsi2 = gsi_start_bb (new_bb);
+
+ fn = dst_r->u.must_not_throw.failure_decl;
+ x = gimple_build_call (fn, 0);
+ gimple_set_location (x, dst_r->u.must_not_throw.failure_loc);
+ gsi_insert_after (&gsi2, x, GSI_CONTINUE_LINKING);
+
+ slot = pointer_map_insert (mnt_map, dst_r);
+ *slot = lab;
+ }
+ else
+ {
+ lab = (tree) *slot;
+ new_bb = label_to_block (lab);
+ }
+
+ gcc_assert (EDGE_COUNT (bb->succs) == 0);
+ e = make_edge (bb, new_bb, EDGE_FALLTHRU);
+ e->count = bb->count;
+ e->probability = REG_BR_PROB_BASE;
+ }
+ else
+ {
+ edge_iterator ei;
+ tree dst_nr = build_int_cst (NULL, dst_r->index);
+
+ fn = implicit_built_in_decls[BUILT_IN_EH_COPY_VALUES];
+ src_nr = build_int_cst (NULL, src_r->index);
+ x = gimple_build_call (fn, 2, dst_nr, src_nr);
+ gsi_insert_before (&gsi, x, GSI_SAME_STMT);
+
+ /* Update the flags for the outgoing edge. */
+ e = single_succ_edge (bb);
+ gcc_assert (e->flags & EDGE_EH);
+ e->flags = (e->flags & ~EDGE_EH) | EDGE_FALLTHRU;
+
+ /* If there are no more EH users of the landing pad, delete it. */
+ FOR_EACH_EDGE (e, ei, e->dest->preds)
+ if (e->flags & EDGE_EH)
+ break;
+ if (e == NULL)
+ {
+ eh_landing_pad lp = get_eh_landing_pad_from_number (lp_nr);
+ remove_eh_landing_pad (lp);
+ }
+ }
+
+ ret = true;
+ }
+ else
+ {
+ tree var;
+
+ /* When we don't have a destination region, this exception escapes
+ up the call chain. We resolve this by generating a call to the
+ _Unwind_Resume library function. */
+
+ /* The ARM EABI redefines _Unwind_Resume as __cxa_end_cleanup
+ with no arguments for C++ and Java. Check for that. */
+ if (src_r->use_cxa_end_cleanup)
+ {
+ fn = implicit_built_in_decls[BUILT_IN_CXA_END_CLEANUP];
+ x = gimple_build_call (fn, 0);
+ gsi_insert_before (&gsi, x, GSI_SAME_STMT);
+ }
+ else
+ {
+ fn = implicit_built_in_decls[BUILT_IN_EH_POINTER];
+ src_nr = build_int_cst (NULL, src_r->index);
+ x = gimple_build_call (fn, 1, src_nr);
+ var = create_tmp_var (ptr_type_node, NULL);
+ var = make_ssa_name (var, x);
+ gimple_call_set_lhs (x, var);
+ gsi_insert_before (&gsi, x, GSI_SAME_STMT);
+
+ fn = implicit_built_in_decls[BUILT_IN_UNWIND_RESUME];
+ x = gimple_build_call (fn, 1, var);
+ gsi_insert_before (&gsi, x, GSI_SAME_STMT);
+ }
+
+ gcc_assert (EDGE_COUNT (bb->succs) == 0);
+ }
+
+ gsi_remove (&gsi, true);
+
+ return ret;
+}
+
+static unsigned
+execute_lower_resx (void)
+{
+ basic_block bb;
+ struct pointer_map_t *mnt_map;
+ bool dominance_invalidated = false;
+ bool any_rewritten = false;
+
+ mnt_map = pointer_map_create ();
+
+ FOR_EACH_BB (bb)
+ {
+ gimple last = last_stmt (bb);
+ if (last && is_gimple_resx (last))
+ {
+ dominance_invalidated |= lower_resx (bb, last, mnt_map);
+ any_rewritten = true;
+ }
+ }
+
+ pointer_map_destroy (mnt_map);
+
+ if (dominance_invalidated)
+ {
+ free_dominance_info (CDI_DOMINATORS);
+ free_dominance_info (CDI_POST_DOMINATORS);
+ }
+
+ return any_rewritten ? TODO_update_ssa_only_virtuals : 0;
+}
+
+static bool
+gate_lower_resx (void)
+{
+ return flag_exceptions != 0;
+}
+
+struct gimple_opt_pass pass_lower_resx =
+{
+ {
+ GIMPLE_PASS,
+ "resx", /* name */
+ gate_lower_resx, /* gate */
+ execute_lower_resx, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_TREE_EH, /* tv_id */
+ PROP_gimple_lcf, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func | TODO_verify_flow /* todo_flags_finish */
+ }
+};
+
+
+/* At the end of inlining, we can lower EH_DISPATCH. Return true when
+ we have found some duplicate labels and removed some edges. */
+
+static bool
+lower_eh_dispatch (basic_block src, gimple stmt)
+{
+ gimple_stmt_iterator gsi;
+ int region_nr;
+ eh_region r;
+ tree filter, fn;
+ gimple x;
+ bool redirected = false;
+
+ region_nr = gimple_eh_dispatch_region (stmt);
+ r = get_eh_region_from_number (region_nr);
+
+ gsi = gsi_last_bb (src);
+
+ switch (r->type)
+ {
+ case ERT_TRY:
+ {
+ VEC (tree, heap) *labels = NULL;
+ tree default_label = NULL;
+ eh_catch c;
+ edge_iterator ei;
+ edge e;
+ struct pointer_set_t *seen_values = pointer_set_create ();
+
+ /* Collect the labels for a switch. Zero the post_landing_pad
+ field becase we'll no longer have anything keeping these labels
+ in existance and the optimizer will be free to merge these
+ blocks at will. */
+ for (c = r->u.eh_try.first_catch; c ; c = c->next_catch)
+ {
+ tree tp_node, flt_node, lab = c->label;
+ bool have_label = false;
+
+ c->label = NULL;
+ tp_node = c->type_list;
+ flt_node = c->filter_list;
+
+ if (tp_node == NULL)
+ {
+ default_label = lab;
+ break;
+ }
+ do
+ {
+ /* Filter out duplicate labels that arise when this handler
+ is shadowed by an earlier one. When no labels are
+ attached to the handler anymore, we remove
+ the corresponding edge and then we delete unreachable
+ blocks at the end of this pass. */
+ if (! pointer_set_contains (seen_values, TREE_VALUE (flt_node)))
+ {
+ tree t = build3 (CASE_LABEL_EXPR, void_type_node,
+ TREE_VALUE (flt_node), NULL, lab);
+ VEC_safe_push (tree, heap, labels, t);
+ pointer_set_insert (seen_values, TREE_VALUE (flt_node));
+ have_label = true;
+ }
+
+ tp_node = TREE_CHAIN (tp_node);
+ flt_node = TREE_CHAIN (flt_node);
+ }
+ while (tp_node);
+ if (! have_label)
+ {
+ remove_edge (find_edge (src, label_to_block (lab)));
+ redirected = true;
+ }
+ }
+
+ /* Clean up the edge flags. */
+ FOR_EACH_EDGE (e, ei, src->succs)
+ {
+ if (e->flags & EDGE_FALLTHRU)
+ {
+ /* If there was no catch-all, use the fallthru edge. */
+ if (default_label == NULL)
+ default_label = gimple_block_label (e->dest);
+ e->flags &= ~EDGE_FALLTHRU;
+ }
+ }
+ gcc_assert (default_label != NULL);
+
+ /* Don't generate a switch if there's only a default case.
+ This is common in the form of try { A; } catch (...) { B; }. */
+ if (labels == NULL)
+ {
+ e = single_succ_edge (src);
+ e->flags |= EDGE_FALLTHRU;
+ }
+ else
+ {
+ fn = implicit_built_in_decls[BUILT_IN_EH_FILTER];
+ x = gimple_build_call (fn, 1, build_int_cst (NULL, region_nr));
+ filter = create_tmp_var (TREE_TYPE (TREE_TYPE (fn)), NULL);
+ filter = make_ssa_name (filter, x);
+ gimple_call_set_lhs (x, filter);
+ gsi_insert_before (&gsi, x, GSI_SAME_STMT);
+
+ /* Turn the default label into a default case. */
+ default_label = build3 (CASE_LABEL_EXPR, void_type_node,
+ NULL, NULL, default_label);
+ sort_case_labels (labels);
+
+ x = gimple_build_switch_vec (filter, default_label, labels);
+ gsi_insert_before (&gsi, x, GSI_SAME_STMT);
+
+ VEC_free (tree, heap, labels);
+ }
+ pointer_set_destroy (seen_values);
+ }
+ break;
+
+ case ERT_ALLOWED_EXCEPTIONS:
+ {
+ edge b_e = BRANCH_EDGE (src);
+ edge f_e = FALLTHRU_EDGE (src);
+
+ fn = implicit_built_in_decls[BUILT_IN_EH_FILTER];
+ x = gimple_build_call (fn, 1, build_int_cst (NULL, region_nr));
+ filter = create_tmp_var (TREE_TYPE (TREE_TYPE (fn)), NULL);
+ filter = make_ssa_name (filter, x);
+ gimple_call_set_lhs (x, filter);
+ gsi_insert_before (&gsi, x, GSI_SAME_STMT);
+
+ r->u.allowed.label = NULL;
+ x = gimple_build_cond (EQ_EXPR, filter,
+ build_int_cst (TREE_TYPE (filter),
+ r->u.allowed.filter),
+ NULL_TREE, NULL_TREE);
+ gsi_insert_before (&gsi, x, GSI_SAME_STMT);
+
+ b_e->flags = b_e->flags | EDGE_TRUE_VALUE;
+ f_e->flags = (f_e->flags & ~EDGE_FALLTHRU) | EDGE_FALSE_VALUE;
+ }
+ break;
+
+ default:
+ gcc_unreachable ();
+ }
+
+ /* Replace the EH_DISPATCH with the SWITCH or COND generated above. */
+ gsi_remove (&gsi, true);
+ return redirected;
+}
+
+static unsigned
+execute_lower_eh_dispatch (void)
+{
+ basic_block bb;
+ bool any_rewritten = false;
+ bool redirected = false;
+
+ assign_filter_values ();
+
+ FOR_EACH_BB (bb)
+ {
+ gimple last = last_stmt (bb);
+ if (last && gimple_code (last) == GIMPLE_EH_DISPATCH)
+ {
+ redirected |= lower_eh_dispatch (bb, last);
+ any_rewritten = true;
+ }
+ }
+
+ if (redirected)
+ delete_unreachable_blocks ();
+ return any_rewritten ? TODO_update_ssa_only_virtuals : 0;
+}
+
+static bool
+gate_lower_eh_dispatch (void)
+{
+ return cfun->eh->region_tree != NULL;
+}
+
+struct gimple_opt_pass pass_lower_eh_dispatch =
+{
+ {
+ GIMPLE_PASS,
+ "ehdisp", /* name */
+ gate_lower_eh_dispatch, /* gate */
+ execute_lower_eh_dispatch, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_TREE_EH, /* tv_id */
+ PROP_gimple_lcf, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func | TODO_verify_flow /* todo_flags_finish */
+ }
+};
+\f
+/* Walk statements, see what regions are really referenced and remove
+ those that are unused. */
+
+static void
+remove_unreachable_handlers (void)
+{
+ sbitmap r_reachable, lp_reachable;
+ eh_region region;
+ eh_landing_pad lp;
+ basic_block bb;
+ int lp_nr, r_nr;
+
+ r_reachable = sbitmap_alloc (VEC_length (eh_region, cfun->eh->region_array));
+ lp_reachable
+ = sbitmap_alloc (VEC_length (eh_landing_pad, cfun->eh->lp_array));
+ sbitmap_zero (r_reachable);
+ sbitmap_zero (lp_reachable);
+
+ FOR_EACH_BB (bb)
+ {
+ gimple_stmt_iterator gsi = gsi_start_bb (bb);
+
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
+ lp_nr = lookup_stmt_eh_lp (stmt);
+
+ /* Negative LP numbers are MUST_NOT_THROW regions which
+ are not considered BB enders. */
+ if (lp_nr < 0)
+ SET_BIT (r_reachable, -lp_nr);
+
+ /* Positive LP numbers are real landing pads, are are BB enders. */
+ else if (lp_nr > 0)
+ {
+ gcc_assert (gsi_one_before_end_p (gsi));
+ region = get_eh_region_from_lp_number (lp_nr);
+ SET_BIT (r_reachable, region->index);
+ SET_BIT (lp_reachable, lp_nr);
+ }
+ }
+ }
+
+ if (dump_file)
+ {
+ fprintf (dump_file, "Before removal of unreachable regions:\n");
+ dump_eh_tree (dump_file, cfun);
+ fprintf (dump_file, "Reachable regions: ");
+ dump_sbitmap_file (dump_file, r_reachable);
+ fprintf (dump_file, "Reachable landing pads: ");
+ dump_sbitmap_file (dump_file, lp_reachable);
+ }
+
+ for (r_nr = 1;
+ VEC_iterate (eh_region, cfun->eh->region_array, r_nr, region); ++r_nr)
+ if (region && !TEST_BIT (r_reachable, r_nr))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Removing unreachable region %d\n", r_nr);
+ remove_eh_handler (region);
+ }
+
+ for (lp_nr = 1;
+ VEC_iterate (eh_landing_pad, cfun->eh->lp_array, lp_nr, lp); ++lp_nr)
+ if (lp && !TEST_BIT (lp_reachable, lp_nr))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Removing unreachable landing pad %d\n", lp_nr);
+ remove_eh_landing_pad (lp);
+ }
+
+ if (dump_file)
+ {
+ fprintf (dump_file, "\n\nAfter removal of unreachable regions:\n");
+ dump_eh_tree (dump_file, cfun);
+ fprintf (dump_file, "\n\n");
+ }
+
+ sbitmap_free (r_reachable);
+ sbitmap_free (lp_reachable);
+
+#ifdef ENABLE_CHECKING
+ verify_eh_tree (cfun);
+#endif
+}
+
+/* Remove regions that do not have landing pads. This assumes
+ that remove_unreachable_handlers has already been run, and
+ that we've just manipulated the landing pads since then. */
+
+static void
+remove_unreachable_handlers_no_lp (void)
+{
+ eh_region r;
+ int i;
+
+ for (i = 1; VEC_iterate (eh_region, cfun->eh->region_array, i, r); ++i)
+ if (r && r->landing_pads == NULL && r->type != ERT_MUST_NOT_THROW)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Removing unreachable region %d\n", i);
+ remove_eh_handler (r);
+ }
+}
+
+/* Undo critical edge splitting on an EH landing pad. Earlier, we
+ optimisticaly split all sorts of edges, including EH edges. The
+ optimization passes in between may not have needed them; if not,
+ we should undo the split.
+
+ Recognize this case by having one EH edge incoming to the BB and
+ one normal edge outgoing; BB should be empty apart from the
+ post_landing_pad label.
+
+ Note that this is slightly different from the empty handler case
+ handled by cleanup_empty_eh, in that the actual handler may yet
+ have actual code but the landing pad has been separated from the
+ handler. As such, cleanup_empty_eh relies on this transformation
+ having been done first. */
+
+static bool
+unsplit_eh (eh_landing_pad lp)
+{
+ basic_block bb = label_to_block (lp->post_landing_pad);
+ gimple_stmt_iterator gsi;
+ edge e_in, e_out;
+
+ /* Quickly check the edge counts on BB for singularity. */
+ if (EDGE_COUNT (bb->preds) != 1 || EDGE_COUNT (bb->succs) != 1)
+ return false;
+ e_in = EDGE_PRED (bb, 0);
+ e_out = EDGE_SUCC (bb, 0);
+
+ /* Input edge must be EH and output edge must be normal. */
+ if ((e_in->flags & EDGE_EH) == 0 || (e_out->flags & EDGE_EH) != 0)
+ return false;
+
+ /* The block must be empty except for the labels and debug insns. */
+ gsi = gsi_after_labels (bb);
+ if (!gsi_end_p (gsi) && is_gimple_debug (gsi_stmt (gsi)))
+ gsi_next_nondebug (&gsi);
+ if (!gsi_end_p (gsi))
+ return false;
+
+ /* The destination block must not already have a landing pad
+ for a different region. */
+ for (gsi = gsi_start_bb (e_out->dest); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
+ tree lab;
+ int lp_nr;
+
+ if (gimple_code (stmt) != GIMPLE_LABEL)
+ break;
+ lab = gimple_label_label (stmt);
+ lp_nr = EH_LANDING_PAD_NR (lab);
+ if (lp_nr && get_eh_region_from_lp_number (lp_nr) != lp->region)
+ return false;
+ }
+
+ /* The new destination block must not already be a destination of
+ the source block, lest we merge fallthru and eh edges and get
+ all sorts of confused. */
+ if (find_edge (e_in->src, e_out->dest))
+ return false;
+
+ /* ??? We can get degenerate phis due to cfg cleanups. I would have
+ thought this should have been cleaned up by a phicprop pass, but
+ that doesn't appear to handle virtuals. Propagate by hand. */
+ if (!gimple_seq_empty_p (phi_nodes (bb)))
+ {
+ for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); )
+ {
+ gimple use_stmt, phi = gsi_stmt (gsi);
+ tree lhs = gimple_phi_result (phi);
+ tree rhs = gimple_phi_arg_def (phi, 0);
+ use_operand_p use_p;
+ imm_use_iterator iter;
+
+ FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs)
+ {
+ FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
+ SET_USE (use_p, rhs);
+ }
+
+ if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs))
+ SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rhs) = 1;
+
+ remove_phi_node (&gsi, true);
+ }
+ }
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, "Unsplit EH landing pad %d to block %i.\n",
+ lp->index, e_out->dest->index);
+
+ /* Redirect the edge. Since redirect_eh_edge_1 expects to be moving
+ a successor edge, humor it. But do the real CFG change with the
+ predecessor of E_OUT in order to preserve the ordering of arguments
+ to the PHI nodes in E_OUT->DEST. */
+ redirect_eh_edge_1 (e_in, e_out->dest, false);
+ redirect_edge_pred (e_out, e_in->src);
+ e_out->flags = e_in->flags;
+ e_out->probability = e_in->probability;
+ e_out->count = e_in->count;
+ remove_edge (e_in);
+
+ return true;
+}
+
+/* Examine each landing pad block and see if it matches unsplit_eh. */
+
+static bool
+unsplit_all_eh (void)
+{
+ bool changed = false;
+ eh_landing_pad lp;
+ int i;
+
+ for (i = 1; VEC_iterate (eh_landing_pad, cfun->eh->lp_array, i, lp); ++i)
+ if (lp)
+ changed |= unsplit_eh (lp);
+
+ return changed;
+}
+
+/* A subroutine of cleanup_empty_eh. Redirect all EH edges incoming
+ to OLD_BB to NEW_BB; return true on success, false on failure.
+
+ OLD_BB_OUT is the edge into NEW_BB from OLD_BB, so if we miss any
+ PHI variables from OLD_BB we can pick them up from OLD_BB_OUT.
+ Virtual PHIs may be deleted and marked for renaming. */
+
+static bool
+cleanup_empty_eh_merge_phis (basic_block new_bb, basic_block old_bb,
+ edge old_bb_out, bool change_region)
+{
+ gimple_stmt_iterator ngsi, ogsi;
+ edge_iterator ei;
+ edge e;
+ bitmap rename_virts;
+ bitmap ophi_handled;
+
+ FOR_EACH_EDGE (e, ei, old_bb->preds)
+ redirect_edge_var_map_clear (e);
+
+ ophi_handled = BITMAP_ALLOC (NULL);
+ rename_virts = BITMAP_ALLOC (NULL);
+
+ /* First, iterate through the PHIs on NEW_BB and set up the edge_var_map
+ for the edges we're going to move. */
+ for (ngsi = gsi_start_phis (new_bb); !gsi_end_p (ngsi); gsi_next (&ngsi))
+ {
+ gimple ophi, nphi = gsi_stmt (ngsi);
+ tree nresult, nop;
+
+ nresult = gimple_phi_result (nphi);
+ nop = gimple_phi_arg_def (nphi, old_bb_out->dest_idx);
+
+ /* Find the corresponding PHI in OLD_BB so we can forward-propagate
+ the source ssa_name. */
+ ophi = NULL;
+ for (ogsi = gsi_start_phis (old_bb); !gsi_end_p (ogsi); gsi_next (&ogsi))
+ {
+ ophi = gsi_stmt (ogsi);
+ if (gimple_phi_result (ophi) == nop)
+ break;
+ ophi = NULL;
+ }
+
+ /* If we did find the corresponding PHI, copy those inputs. */
+ if (ophi)
+ {
+ bitmap_set_bit (ophi_handled, SSA_NAME_VERSION (nop));
+ FOR_EACH_EDGE (e, ei, old_bb->preds)
+ {
+ location_t oloc;
+ tree oop;
+
+ if ((e->flags & EDGE_EH) == 0)
+ continue;
+ oop = gimple_phi_arg_def (ophi, e->dest_idx);
+ oloc = gimple_phi_arg_location (ophi, e->dest_idx);
+ redirect_edge_var_map_add (e, nresult, oop, oloc);
+ }
+ }
+ /* If we didn't find the PHI, but it's a VOP, remember to rename
+ it later, assuming all other tests succeed. */
+ else if (!is_gimple_reg (nresult))
+ bitmap_set_bit (rename_virts, SSA_NAME_VERSION (nresult));
+ /* If we didn't find the PHI, and it's a real variable, we know
+ from the fact that OLD_BB is tree_empty_eh_handler_p that the
+ variable is unchanged from input to the block and we can simply
+ re-use the input to NEW_BB from the OLD_BB_OUT edge. */
+ else
+ {
+ location_t nloc
+ = gimple_phi_arg_location (nphi, old_bb_out->dest_idx);
+ FOR_EACH_EDGE (e, ei, old_bb->preds)
+ redirect_edge_var_map_add (e, nresult, nop, nloc);
+ }
+ }
+
+ /* Second, verify that all PHIs from OLD_BB have been handled. If not,
+ we don't know what values from the other edges into NEW_BB to use. */
+ for (ogsi = gsi_start_phis (old_bb); !gsi_end_p (ogsi); gsi_next (&ogsi))
+ {
+ gimple ophi = gsi_stmt (ogsi);
+ tree oresult = gimple_phi_result (ophi);
+ if (!bitmap_bit_p (ophi_handled, SSA_NAME_VERSION (oresult)))
+ goto fail;
+ }
+
+ /* At this point we know that the merge will succeed. Remove the PHI
+ nodes for the virtuals that we want to rename. */
+ if (!bitmap_empty_p (rename_virts))
+ {
+ for (ngsi = gsi_start_phis (new_bb); !gsi_end_p (ngsi); )
+ {
+ gimple nphi = gsi_stmt (ngsi);
+ tree nresult = gimple_phi_result (nphi);
+ if (bitmap_bit_p (rename_virts, SSA_NAME_VERSION (nresult)))
+ {
+ mark_virtual_phi_result_for_renaming (nphi);
+ remove_phi_node (&ngsi, true);
+ }
+ else
+ gsi_next (&ngsi);
+ }
+ }
+
+ /* Finally, move the edges and update the PHIs. */
+ for (ei = ei_start (old_bb->preds); (e = ei_safe_edge (ei)); )
+ if (e->flags & EDGE_EH)
+ {
+ redirect_eh_edge_1 (e, new_bb, change_region);
+ redirect_edge_succ (e, new_bb);
+ flush_pending_stmts (e);
+ }
+ else
+ ei_next (&ei);
+
+ BITMAP_FREE (ophi_handled);
+ BITMAP_FREE (rename_virts);
+ return true;
+
+ fail:
+ FOR_EACH_EDGE (e, ei, old_bb->preds)
+ redirect_edge_var_map_clear (e);
+ BITMAP_FREE (ophi_handled);
+ BITMAP_FREE (rename_virts);
+ return false;
+}
+
+/* A subroutine of cleanup_empty_eh. Move a landing pad LP from its
+ old region to NEW_REGION at BB. */
+
+static void
+cleanup_empty_eh_move_lp (basic_block bb, edge e_out,
+ eh_landing_pad lp, eh_region new_region)
+{
+ gimple_stmt_iterator gsi;
+ eh_landing_pad *pp;
+
+ for (pp = &lp->region->landing_pads; *pp != lp; pp = &(*pp)->next_lp)
+ continue;
+ *pp = lp->next_lp;
+
+ lp->region = new_region;
+ lp->next_lp = new_region->landing_pads;
+ new_region->landing_pads = lp;
+
+ /* Delete the RESX that was matched within the empty handler block. */
+ gsi = gsi_last_bb (bb);
+ mark_virtual_ops_for_renaming (gsi_stmt (gsi));
+ gsi_remove (&gsi, true);
+
+ /* Clean up E_OUT for the fallthru. */
+ e_out->flags = (e_out->flags & ~EDGE_EH) | EDGE_FALLTHRU;
+ e_out->probability = REG_BR_PROB_BASE;
+}
+
+/* A subroutine of cleanup_empty_eh. Handle more complex cases of
+ unsplitting than unsplit_eh was prepared to handle, e.g. when
+ multiple incoming edges and phis are involved. */
+
+static bool
+cleanup_empty_eh_unsplit (basic_block bb, edge e_out, eh_landing_pad lp)
+{
+ gimple_stmt_iterator gsi;
+ tree lab;
+
+ /* We really ought not have totally lost everything following
+ a landing pad label. Given that BB is empty, there had better
+ be a successor. */
+ gcc_assert (e_out != NULL);
+
+ /* The destination block must not already have a landing pad
+ for a different region. */
+ lab = NULL;
+ for (gsi = gsi_start_bb (e_out->dest); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
+ int lp_nr;
+
+ if (gimple_code (stmt) != GIMPLE_LABEL)
+ break;
+ lab = gimple_label_label (stmt);
+ lp_nr = EH_LANDING_PAD_NR (lab);
+ if (lp_nr && get_eh_region_from_lp_number (lp_nr) != lp->region)
+ return false;
+ }
+
+ /* Attempt to move the PHIs into the successor block. */
+ if (cleanup_empty_eh_merge_phis (e_out->dest, bb, e_out, false))
+ {
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file,
+ "Unsplit EH landing pad %d to block %i "
+ "(via cleanup_empty_eh).\n",
+ lp->index, e_out->dest->index);
+ return true;
+ }
+
+ return false;
+}
+
+/* Examine the block associated with LP to determine if it's an empty
+ handler for its EH region. If so, attempt to redirect EH edges to
+ an outer region. Return true the CFG was updated in any way. This
+ is similar to jump forwarding, just across EH edges. */
+
+static bool
+cleanup_empty_eh (eh_landing_pad lp)
+{
+ basic_block bb = label_to_block (lp->post_landing_pad);
+ gimple_stmt_iterator gsi;
+ gimple resx;
+ eh_region new_region;
+ edge_iterator ei;
+ edge e, e_out;
+ bool has_non_eh_pred;
+ int new_lp_nr;
+
+ /* There can be zero or one edges out of BB. This is the quickest test. */
+ switch (EDGE_COUNT (bb->succs))
+ {
+ case 0:
+ e_out = NULL;
+ break;
+ case 1:
+ e_out = EDGE_SUCC (bb, 0);
+ break;
+ default:
+ return false;
+ }
+ gsi = gsi_after_labels (bb);
+
+ /* Make sure to skip debug statements. */
+ if (!gsi_end_p (gsi) && is_gimple_debug (gsi_stmt (gsi)))
+ gsi_next_nondebug (&gsi);
+
+ /* If the block is totally empty, look for more unsplitting cases. */
+ if (gsi_end_p (gsi))
+ return cleanup_empty_eh_unsplit (bb, e_out, lp);
+
+ /* The block should consist only of a single RESX statement. */
+ resx = gsi_stmt (gsi);
+ if (!is_gimple_resx (resx))
+ return false;
+ gcc_assert (gsi_one_before_end_p (gsi));
+
+ /* Determine if there are non-EH edges, or resx edges into the handler. */
+ has_non_eh_pred = false;
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ if (!(e->flags & EDGE_EH))
+ has_non_eh_pred = true;
+
+ /* Find the handler that's outer of the empty handler by looking at
+ where the RESX instruction was vectored. */
+ new_lp_nr = lookup_stmt_eh_lp (resx);
+ new_region = get_eh_region_from_lp_number (new_lp_nr);
+
+ /* If there's no destination region within the current function,
+ redirection is trivial via removing the throwing statements from
+ the EH region, removing the EH edges, and allowing the block
+ to go unreachable. */
+ if (new_region == NULL)
+ {
+ gcc_assert (e_out == NULL);
+ for (ei = ei_start (bb->preds); (e = ei_safe_edge (ei)); )
+ if (e->flags & EDGE_EH)
+ {
+ gimple stmt = last_stmt (e->src);
+ remove_stmt_from_eh_lp (stmt);
+ remove_edge (e);
+ }
+ else
+ ei_next (&ei);
+ goto succeed;
+ }
+
+ /* If the destination region is a MUST_NOT_THROW, allow the runtime
+ to handle the abort and allow the blocks to go unreachable. */
+ if (new_region->type == ERT_MUST_NOT_THROW)
+ {
+ for (ei = ei_start (bb->preds); (e = ei_safe_edge (ei)); )
+ if (e->flags & EDGE_EH)
+ {
+ gimple stmt = last_stmt (e->src);
+ remove_stmt_from_eh_lp (stmt);
+ add_stmt_to_eh_lp (stmt, new_lp_nr);
+ remove_edge (e);
+ }
+ else
+ ei_next (&ei);
+ goto succeed;
+ }
+
+ /* Try to redirect the EH edges and merge the PHIs into the destination
+ landing pad block. If the merge succeeds, we'll already have redirected
+ all the EH edges. The handler itself will go unreachable if there were
+ no normal edges. */
+ if (cleanup_empty_eh_merge_phis (e_out->dest, bb, e_out, true))
+ goto succeed;
+
+ /* Finally, if all input edges are EH edges, then we can (potentially)
+ reduce the number of transfers from the runtime by moving the landing
+ pad from the original region to the new region. This is a win when
+ we remove the last CLEANUP region along a particular exception
+ propagation path. Since nothing changes except for the region with
+ which the landing pad is associated, the PHI nodes do not need to be
+ adjusted at all. */
+ if (!has_non_eh_pred)
+ {
+ cleanup_empty_eh_move_lp (bb, e_out, lp, new_region);
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, "Empty EH handler %i moved to EH region %i.\n",
+ lp->index, new_region->index);
+
+ /* ??? The CFG didn't change, but we may have rendered the
+ old EH region unreachable. Trigger a cleanup there. */
+ return true;
+ }
+
+ return false;
+
+ succeed:
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, "Empty EH handler %i removed.\n", lp->index);
+ remove_eh_landing_pad (lp);
+ return true;
+}
+
+/* Do a post-order traversal of the EH region tree. Examine each
+ post_landing_pad block and see if we can eliminate it as empty. */
+
+static bool
+cleanup_all_empty_eh (void)
+{
+ bool changed = false;
+ eh_landing_pad lp;
+ int i;
+
+ for (i = 1; VEC_iterate (eh_landing_pad, cfun->eh->lp_array, i, lp); ++i)
+ if (lp)
+ changed |= cleanup_empty_eh (lp);
+
+ return changed;
+}
+
+/* Perform cleanups and lowering of exception handling
+ 1) cleanups regions with handlers doing nothing are optimized out
+ 2) MUST_NOT_THROW regions that became dead because of 1) are optimized out
+ 3) Info about regions that are containing instructions, and regions
+ reachable via local EH edges is collected
+ 4) Eh tree is pruned for regions no longer neccesary.
+
+ TODO: Push MUST_NOT_THROW regions to the root of the EH tree.
+ Unify those that have the same failure decl and locus.
+*/
+
+static unsigned int
+execute_cleanup_eh (void)
+{
+ /* Do this first: unsplit_all_eh and cleanup_all_empty_eh can die
+ looking up unreachable landing pads. */
+ remove_unreachable_handlers ();
+
+ /* Watch out for the region tree vanishing due to all unreachable. */
+ if (cfun->eh->region_tree && optimize)
+ {
+ bool changed = false;
+
+ changed |= unsplit_all_eh ();
+ changed |= cleanup_all_empty_eh ();
+
+ if (changed)
+ {
+ free_dominance_info (CDI_DOMINATORS);
+ free_dominance_info (CDI_POST_DOMINATORS);
+
+ /* We delayed all basic block deletion, as we may have performed
+ cleanups on EH edges while non-EH edges were still present. */
+ delete_unreachable_blocks ();
+
+ /* We manipulated the landing pads. Remove any region that no
+ longer has a landing pad. */
+ remove_unreachable_handlers_no_lp ();
+
+ return TODO_cleanup_cfg | TODO_update_ssa_only_virtuals;
+ }
+ }
+
+ return 0;
+}
+
+static bool
+gate_cleanup_eh (void)
+{
+ return cfun->eh != NULL && cfun->eh->region_tree != NULL;
+}
+
+struct gimple_opt_pass pass_cleanup_eh = {
+ {
+ GIMPLE_PASS,
+ "ehcleanup", /* name */
+ gate_cleanup_eh, /* gate */
+ execute_cleanup_eh, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_TREE_EH, /* tv_id */
+ PROP_gimple_lcf, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func /* todo_flags_finish */
+ }
+};
+\f
+/* Verify that BB containing STMT as the last statement, has precisely the
+ edge that make_eh_edges would create. */
+
+bool
+verify_eh_edges (gimple stmt)
+{
+ basic_block bb = gimple_bb (stmt);
+ eh_landing_pad lp = NULL;
+ int lp_nr;
+ edge_iterator ei;
+ edge e, eh_edge;
+
+ lp_nr = lookup_stmt_eh_lp (stmt);
+ if (lp_nr > 0)
+ lp = get_eh_landing_pad_from_number (lp_nr);
+
+ eh_edge = NULL;
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ {
+ if (e->flags & EDGE_EH)
+ {
+ if (eh_edge)
+ {
+ error ("BB %i has multiple EH edges", bb->index);
+ return true;
+ }
+ else
+ eh_edge = e;
+ }
+ }
+
+ if (lp == NULL)
+ {
+ if (eh_edge)
+ {
+ error ("BB %i can not throw but has an EH edge", bb->index);
+ return true;
+ }
+ return false;
+ }
+
+ if (!stmt_could_throw_p (stmt))
+ {
+ error ("BB %i last statement has incorrectly set lp", bb->index);
+ return true;
+ }
+
+ if (eh_edge == NULL)
+ {
+ error ("BB %i is missing an EH edge", bb->index);
+ return true;
+ }
+
+ if (eh_edge->dest != label_to_block (lp->post_landing_pad))
+ {
+ error ("Incorrect EH edge %i->%i", bb->index, eh_edge->dest->index);
+ return true;
+ }
+
+ return false;
+}
+
+/* Similarly, but handle GIMPLE_EH_DISPATCH specifically. */
+
+bool
+verify_eh_dispatch_edge (gimple stmt)
+{
+ eh_region r;
+ eh_catch c;
+ basic_block src, dst;
+ bool want_fallthru = true;
+ edge_iterator ei;
+ edge e, fall_edge;
+
+ r = get_eh_region_from_number (gimple_eh_dispatch_region (stmt));
+ src = gimple_bb (stmt);
+
+ FOR_EACH_EDGE (e, ei, src->succs)
+ gcc_assert (e->aux == NULL);
+
+ switch (r->type)
+ {
+ case ERT_TRY:
+ for (c = r->u.eh_try.first_catch; c ; c = c->next_catch)
+ {
+ dst = label_to_block (c->label);
+ e = find_edge (src, dst);
+ if (e == NULL)
+ {
+ error ("BB %i is missing an edge", src->index);
+ return true;
+ }
+ e->aux = (void *)e;
+
+ /* A catch-all handler doesn't have a fallthru. */
+ if (c->type_list == NULL)
+ {
+ want_fallthru = false;
+ break;
+ }
+ }
+ break;
+
+ case ERT_ALLOWED_EXCEPTIONS:
+ dst = label_to_block (r->u.allowed.label);
+ e = find_edge (src, dst);
+ if (e == NULL)
+ {
+ error ("BB %i is missing an edge", src->index);
+ return true;
+ }
+ e->aux = (void *)e;
+ break;
+
+ default:
+ gcc_unreachable ();
+ }
+
+ fall_edge = NULL;
+ FOR_EACH_EDGE (e, ei, src->succs)
+ {
+ if (e->flags & EDGE_FALLTHRU)
+ {
+ if (fall_edge != NULL)
+ {
+ error ("BB %i too many fallthru edges", src->index);
+ return true;
+ }
+ fall_edge = e;
+ }
+ else if (e->aux)
+ e->aux = NULL;
+ else
+ {
+ error ("BB %i has incorrect edge", src->index);
+ return true;
+ }
+ }
+ if ((fall_edge != NULL) ^ want_fallthru)
+ {
+ error ("BB %i has incorrect fallthru edge", src->index);
+ return true;
+ }
+
+ return false;
+}
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