re PR tree-optimization/87465 (Loop removal regression)

2018-10-01  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/87465
	* tree-ssa-loop-ivcanon.c (tree_estimate_loop_size): Fix typo
	causing branch miscounts.

	* gcc.dg/tree-ssa/cunroll-15.c: New testcase.

From-SVN: r264758

gcc/ChangeLog

+2018-10-01  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/87465
+	* tree-ssa-loop-ivcanon.c (tree_estimate_loop_size): Fix typo
+	causing branch miscounts.
+
 2018-10-01  Tamar Christina  <tamar.christina@arm.com>
 
 	* common/config/aarch64/aarch64-common.c (TARGET_OPTION_DEFAULT_PARAM,

gcc/testsuite/ChangeLog

+2018-10-01  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/87465
+	* gcc.dg/tree-ssa/cunroll-15.c: New testcase.
+
 2018-10-01  Tamar Christina  <tamar.christina@arm.com>
 
 	PR target/86486

gcc/testsuite/gcc.dg/tree-ssa/cunroll-15.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -funroll-loops -fdump-tree-cunroll-optimized -fdump-tree-optimized" } */
+
+int Test(void)
+{
+  int c = 0;
+  const int in[4] = {4,3,4,4};
+  for (unsigned i = 0; i < 4; i++) {
+      for (unsigned j = 0; j < i; j++) {
+	  if (in[i] == in[j])
+	    break;
+	  else 
+	    ++c;
+      }
+  }
+  return c;
+}
+
+/* { dg-final { scan-tree-dump-times "optimized:\[^\n\r\]*completely unrolled" 2 "cunroll" } } */
+/* When SLP vectorization is enabled the following will fail because DOM
+   doesn't know how to deal with the vectorized initializer of in.  */
+/* { dg-final { scan-tree-dump "return 1;" "optimized" } } */

gcc/tree-ssa-loop-ivcanon.c

@@ -368,8 +368,8 @@ tree_estimate_loop_size (struct loop *loop, edge exit, edge edge_to_cancel,
 	    size->non_call_stmts_on_hot_path++;
 	  if (((gimple_code (stmt) == GIMPLE_COND
 	        && (!constant_after_peeling (gimple_cond_lhs (stmt), stmt, loop)
-		    || constant_after_peeling (gimple_cond_rhs (stmt), stmt,
-					       loop)))
+		    || !constant_after_peeling (gimple_cond_rhs (stmt), stmt,
+						loop)))
 	       || (gimple_code (stmt) == GIMPLE_SWITCH
 		   && !constant_after_peeling (gimple_switch_index (
 						 as_a <gswitch *> (stmt)),