Fix PR44483: incrementally gimplify BB predicates to avoid redundant computations.

2010-06-11  Sebastian Pop  <sebastian.pop@amd.com>

	PR middle-end/44483
	* tree-if-conv.c (bb_predicate_s): New struct.
	(bb_predicate_p): New.
	(bb_has_predicate): New.
	(bb_predicate): New.
	(set_bb_predicate): New.
	(bb_predicate_gimplified_stmts): New.
	(set_bb_predicate_gimplified_stmts): New.
	(add_bb_predicate_gimplified_stmts): New.
	(init_bb_predicate): New.
	(free_bb_predicate): New.
	(is_predicated): Use bb_predicate.
	(add_to_predicate_list): Use bb_predicate and set_bb_predicate.
	(predicate_bbs): Same.  Gimplify the condition of the basic blocks
	before processing their successors.
	(clean_predicate_lists): Removed.
	(find_phi_replacement_condition): Use bb_predicate.
	(process_phi_nodes): Renamed ifconvert_phi_nodes.  Avoid useless
	computations.
	(insert_gimplified_predicates): New.
	(combine_blocks): Call insert_gimplified_predicates.
	(tree_if_conversion): Call free_bb_predicate instead of
	clean_predicate_lists.

	* gcc.dg/tree-ssa/pr44483.c: New.

From-SVN: r160625

gcc/ChangeLog

+2010-06-11  Sebastian Pop  <sebastian.pop@amd.com>
+
+	PR middle-end/44483
+	* tree-if-conv.c (bb_predicate_s): New struct.
+	(bb_predicate_p): New.
+	(bb_has_predicate): New.
+	(bb_predicate): New.
+	(set_bb_predicate): New.
+	(bb_predicate_gimplified_stmts): New.
+	(set_bb_predicate_gimplified_stmts): New.
+	(add_bb_predicate_gimplified_stmts): New.
+	(init_bb_predicate): New.
+	(free_bb_predicate): New.
+	(is_predicated): Use bb_predicate.
+	(add_to_predicate_list): Use bb_predicate and set_bb_predicate.
+	(predicate_bbs): Same.  Gimplify the condition of the basic blocks
+	before processing their successors.
+	(clean_predicate_lists): Removed.
+	(find_phi_replacement_condition): Use bb_predicate.
+	(process_phi_nodes): Renamed ifconvert_phi_nodes.  Avoid useless
+	computations.
+	(insert_gimplified_predicates): New.
+	(combine_blocks): Call insert_gimplified_predicates.
+	(tree_if_conversion): Call free_bb_predicate instead of
+	clean_predicate_lists.
+
 2010-10-11  Paul Brook  <paul@codesourcery.com>
  
 	* doc/invoke.texi: Document ARM -mcpu=cortex-m4.

gcc/testsuite/ChangeLog

+2010-06-11  Sebastian Pop  <sebastian.pop@amd.com>
+
+	PR middle-end/44483
+	* gcc.dg/tree-ssa/pr44483.c: New.
+
 2010-06-11  Paul Brook  <paul@codesourcery.com>
  
 	* g++.dg/other/arm-neon-1.C: New test.

gcc/testsuite/gcc.dg/tree-ssa/pr44483.c

+/* { dg-do compile } */
+/* { dg-options "-c -O3" { target *-*-* } } */
+
+int ffesum (void) {
+  int ch[4], ii, jj, kk;
+  char asc[32];
+
+  for (ii = 0; ii < 4; ii++)
+    {
+      for (jj = 0; jj < 4; jj++)
+        ch[jj] = ii;
+      for (kk = 0; kk < 13; kk++)
+        for (jj = 0; jj < 4; jj += 2)
+          if ((unsigned char) ch[jj] || (unsigned char) ch[jj + 1])
+            ch[jj]++;
+      for (jj = 0; jj < 4; jj++)
+        asc[4 * jj + ii] = ch[jj];
+    }
+  return asc[0];
+}