--- /dev/null
+/* PR tree-optimization/52448 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-cselim -fdump-tree-cselim-details" } */
+
+extern void perhaps_free_something (void);
+
+void f1 (int *p, int a, int b, int cond, int cond2)
+{
+ *p = a;
+ if (cond)
+ perhaps_free_something ();
+ if (cond2)
+ *p = b;
+}
+
+void f2 (int *p, int a, int b, int *cond, int *cond2)
+{
+ int i;
+ *p = a;
+ for (i = 0; cond[i]; i++)
+ {
+ if (cond2[i])
+ *p = b;
+ perhaps_free_something ();
+ }
+}
+
+/* None of the above conditional stores might be made unconditional. */
+/* { dg-final { scan-tree-dump-not "cstore" "cselim" } } */
+/* { dg-final { cleanup-tree-dump "cselim" } } */
struct name_to_bb
{
unsigned int ssa_name_ver;
+ unsigned int phase;
bool store;
HOST_WIDE_INT offset, size;
basic_block bb;
/* The hash table for remembering what we've seen. */
static htab_t seen_ssa_names;
+/* Used for quick clearing of the hash-table when we see calls.
+ Hash entries with phase < nt_call_phase are invalid. */
+static unsigned int nt_call_phase;
+
/* The set of MEM_REFs which can't trap. */
static struct pointer_set_t *nontrap_set;
/* Try to find the last seen MEM_REF through the same
SSA_NAME, which can trap. */
map.ssa_name_ver = SSA_NAME_VERSION (name);
+ map.phase = 0;
map.bb = 0;
map.store = store;
map.offset = tree_low_cst (TREE_OPERAND (exp, 1), 0);
slot = htab_find_slot (seen_ssa_names, &map, INSERT);
n2bb = (struct name_to_bb *) *slot;
- if (n2bb)
+ if (n2bb && n2bb->phase >= nt_call_phase)
found_bb = n2bb->bb;
/* If we've found a trapping MEM_REF, _and_ it dominates EXP
(it's in a basic block on the path from us to the dominator root)
then we can't trap. */
- if (found_bb && found_bb->aux == (void *)1)
+ if (found_bb && (((size_t)found_bb->aux) & 1) == 1)
{
pointer_set_insert (nontrap, exp);
}
/* EXP might trap, so insert it into the hash table. */
if (n2bb)
{
+ n2bb->phase = nt_call_phase;
n2bb->bb = bb;
}
else
{
n2bb = XNEW (struct name_to_bb);
n2bb->ssa_name_ver = SSA_NAME_VERSION (name);
+ n2bb->phase = nt_call_phase;
n2bb->bb = bb;
n2bb->store = store;
n2bb->offset = map.offset;
}
}
+/* Return true when CALL is a call stmt that definitely doesn't
+ free any memory or makes it unavailable otherwise. */
+static bool
+nonfreeing_call_p (gimple call)
+{
+ if (gimple_call_builtin_p (call, BUILT_IN_NORMAL)
+ && gimple_call_flags (call) & ECF_LEAF)
+ switch (DECL_FUNCTION_CODE (gimple_call_fndecl (call)))
+ {
+ /* Just in case these become ECF_LEAF in the future. */
+ case BUILT_IN_FREE:
+ case BUILT_IN_TM_FREE:
+ case BUILT_IN_REALLOC:
+ case BUILT_IN_STACK_RESTORE:
+ return false;
+ default:
+ return true;
+ }
+
+ return false;
+}
+
/* Called by walk_dominator_tree, when entering the block BB. */
static void
nt_init_block (struct dom_walk_data *data ATTRIBUTE_UNUSED, basic_block bb)
{
+ edge e;
+ edge_iterator ei;
gimple_stmt_iterator gsi;
- /* Mark this BB as being on the path to dominator root. */
- bb->aux = (void*)1;
+
+ /* If we haven't seen all our predecessors, clear the hash-table. */
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ if ((((size_t)e->src->aux) & 2) == 0)
+ {
+ nt_call_phase++;
+ break;
+ }
+
+ /* Mark this BB as being on the path to dominator root and as visited. */
+ bb->aux = (void*)(1 | 2);
/* And walk the statements in order. */
for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
gimple stmt = gsi_stmt (gsi);
- if (gimple_assign_single_p (stmt) && !gimple_has_volatile_ops (stmt))
+ if (is_gimple_call (stmt) && !nonfreeing_call_p (stmt))
+ nt_call_phase++;
+ else if (gimple_assign_single_p (stmt) && !gimple_has_volatile_ops (stmt))
{
add_or_mark_expr (bb, gimple_assign_lhs (stmt), nontrap_set, true);
add_or_mark_expr (bb, gimple_assign_rhs1 (stmt), nontrap_set, false);
nt_fini_block (struct dom_walk_data *data ATTRIBUTE_UNUSED, basic_block bb)
{
/* This BB isn't on the path to dominator root anymore. */
- bb->aux = NULL;
+ bb->aux = (void*)2;
}
/* This is the entry point of gathering non trapping memory accesses.
struct pointer_set_t *nontrap;
struct dom_walk_data walk_data;
+ nt_call_phase = 0;
nontrap = pointer_set_create ();
seen_ssa_names = htab_create (128, name_to_bb_hash, name_to_bb_eq,
free);
fini_walk_dominator_tree (&walk_data);
htab_delete (seen_ssa_names);
+ clear_aux_for_blocks ();
return nontrap;
}