===================================================================
@@ -59,7 +59,6 @@ static bool better_p (const_edge, const_
static edge find_best_successor (basic_block);
static edge find_best_predecessor (basic_block);
static int find_trace (basic_block, basic_block *);
-static void tail_duplicate (void);
/* Minimal outgoing edge probability considered for superblock formation. */
static int probability_cutoff;
@@ -224,7 +223,7 @@ find_trace (basic_block bb, basic_block
/* Look for basic blocks in frequency order, construct traces and tail duplicate
if profitable. */
-static void
+static bool
tail_duplicate (void)
{
fibnode_t *blocks = XCNEWVEC (fibnode_t, last_basic_block);
@@ -236,6 +235,7 @@ tail_duplicate (void)
gcov_type cover_insns;
int max_dup_insns;
basic_block bb;
+ bool changed = false;
/* Create an oversized sbitmap to reduce the chance that we need to
resize it. */
@@ -332,6 +332,7 @@ tail_duplicate (void)
bb2->index, copy->index, copy->frequency);
bb2 = copy;
+ changed = true;
}
mark_bb_seen (bb2);
bb = bb2;
@@ -353,6 +354,8 @@ tail_duplicate (void)
free (trace);
free (counts);
fibheap_delete (heap);
+
+ return changed;
}
/* Main entry point to this file. */
@@ -360,6 +363,8 @@ tail_duplicate (void)
static unsigned int
tracer (void)
{
+ bool changed;
+
gcc_assert (current_ir_type () == IR_GIMPLE);
if (n_basic_blocks <= NUM_FIXED_BLOCKS + 1)
@@ -370,15 +375,14 @@ tracer (void)
dump_flow_info (dump_file, dump_flags);
/* Trace formation is done on the fly inside tail_duplicate */
- tail_duplicate ();
+ changed = tail_duplicate ();
+ if (changed)
+ free_dominance_info (CDI_DOMINATORS);
- /* FIXME: We really only need to do this when we know tail duplication
- has altered the CFG. */
- free_dominance_info (CDI_DOMINATORS);
if (dump_file)
dump_flow_info (dump_file, dump_flags);
- return 0;
+ return changed ? TODO_cleanup_cfg : 0;
}
static bool
===================================================================
@@ -1009,18 +1009,28 @@ duplicate_block (basic_block bb, edge e,
{
struct loop *cloop = bb->loop_father;
struct loop *copy = get_loop_copy (cloop);
- add_bb_to_loop (new_bb, copy ? copy : cloop);
- /* If we copied the loop latch block but not the loop, adjust
- loop state.
- ??? If we copied the loop header block but not the loop
- we might either have created a loop copy or a loop with
- multiple entries. In both cases we probably have to
- ditch the loops and arrange for a fixup. */
+ /* If we copied the loop header block but not the loop
+ we have created a loop with multiple entries. Ditch the loop,
+ add the new block to the outer loop and arrange for a fixup. */
if (!copy
- && cloop->latch == bb)
+ && cloop->header == bb)
{
+ add_bb_to_loop (new_bb, loop_outer (cloop));
+ cloop->header = NULL;
cloop->latch = NULL;
- loops_state_set (LOOPS_MAY_HAVE_MULTIPLE_LATCHES);
+ loops_state_set (LOOPS_NEED_FIXUP);
+ }
+ else
+ {
+ add_bb_to_loop (new_bb, copy ? copy : cloop);
+ /* If we copied the loop latch block but not the loop, adjust
+ loop state. */
+ if (!copy
+ && cloop->latch == bb)
+ {
+ cloop->latch = NULL;
+ loops_state_set (LOOPS_MAY_HAVE_MULTIPLE_LATCHES);
+ }
}
}
===================================================================
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-O -ftracer" } */
+
+int **fn1 () __attribute__ ((__const__));
+int main ()
+{
+ int i;
+ i = 0;
+ for (;; i++)
+ if (*fn1 ()[i] && !'a' <= 0 && i <= 'z' || *fn1 ()[0] && 'a' <= 'z')
+ return;
+}