re PR tree-optimization/58459 (Loop invariant is not hoisted out of loop after r202525.)

2013-09-27  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/58459
	* tree-ssa-forwprop.c (forward_propagate_addr_expr): Remove
	restriction not propagating into loops.

	* gcc.dg/tree-ssa/ssa-pre-31.c: New testcase.

From-SVN: r202966

gcc/ChangeLog

+2013-09-27  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/58459
+	* tree-ssa-forwprop.c (forward_propagate_addr_expr): Remove
+	restriction not propagating into loops.
+
 2013-09-26  Florian Weimer  <fw@deneb.enyo.de>
 
 	* tree-ssa.h (walk_use_def_chains_fn, walk_use_def_chains): Delete.

gcc/testsuite/ChangeLog

+2013-09-27  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/58459
+	* gcc.dg/tree-ssa/ssa-pre-31.c: New testcase.
+
 2013-09-26  Bernd Edlinger  <bernd.edlinger@hotmail.de>
 
 	PR fortran/58113

gcc/testsuite/gcc.dg/tree-ssa/ssa-pre-31.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-pre" } */
+
+typedef struct {
+    unsigned int key;
+} S;
+typedef struct s1  {
+    unsigned int key;
+    unsigned int bits;
+    struct s1 *left, *right;
+}S1;
+extern S a[1024];
+static inline int bar( S* p, S1* n )
+{
+  S1 *curr;
+  S1 *next;
+
+  if ( n->left == n )
+    return (int)(p->key == n->key);
+
+  curr = n;
+  next = n->left;
+
+  while (curr->bits > next->bits ) {
+      curr = next;
+      if (p->key & (1 << curr->bits))
+	next = curr->right;
+      else
+	next = curr->left;
+  }
+
+  return (int)(p->key == next->key);
+
+}
+
+int foo (S1 *root, int N)
+{
+  volatile int r;
+  int i,j;
+  for (i=0; i<N; i++)
+    for (j=0;j<1024; j++)
+      r = bar(&a[j], root);
+  return 0;
+} 
+
+/* { dg-final { scan-tree-dump-times "key" 4 "pre" } } */
+/* { dg-final { cleanup-tree-dump "pre" } } */

gcc/tree-ssa-forwprop.c

@@ -1001,7 +1001,6 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs,
 static bool
 forward_propagate_addr_expr (tree name, tree rhs)
 {
-  int stmt_loop_depth = bb_loop_depth (gimple_bb (SSA_NAME_DEF_STMT (name)));
   imm_use_iterator iter;
   gimple use_stmt;
   bool all = true;
@@ -1014,37 +1013,24 @@ forward_propagate_addr_expr (tree name, tree rhs)
 
       /* If the use is not in a simple assignment statement, then
 	 there is nothing we can do.  */
-      if (gimple_code (use_stmt) != GIMPLE_ASSIGN)
+      if (!is_gimple_assign (use_stmt))
 	{
 	  if (!is_gimple_debug (use_stmt))
 	    all = false;
 	  continue;
 	}
 
-      /* If the use is in a deeper loop nest, then we do not want
-	 to propagate non-invariant ADDR_EXPRs into the loop as that
-	 is likely adding expression evaluations into the loop.  */
-      if (bb_loop_depth (gimple_bb (use_stmt)) > stmt_loop_depth
-	  && !is_gimple_min_invariant (rhs))
+      gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt);
+      result = forward_propagate_addr_expr_1 (name, rhs, &gsi,
+					      single_use_p);
+      /* If the use has moved to a different statement adjust
+	 the update machinery for the old statement too.  */
+      if (use_stmt != gsi_stmt (gsi))
 	{
-	  all = false;
-	  continue;
+	  update_stmt (use_stmt);
+	  use_stmt = gsi_stmt (gsi);
 	}
-
-      {
-	gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt);
-	result = forward_propagate_addr_expr_1 (name, rhs, &gsi,
-						single_use_p);
-	/* If the use has moved to a different statement adjust
-	   the update machinery for the old statement too.  */
-	if (use_stmt != gsi_stmt (gsi))
-	  {
-	    update_stmt (use_stmt);
-	    use_stmt = gsi_stmt (gsi);
-	  }
-
-	update_stmt (use_stmt);
-      }
+      update_stmt (use_stmt);
       all &= result;
 
       /* Remove intermediate now unused copy and conversion chains.  */