6860469: remix_address_expressions sets incorrect control causing crash in split_if_with_block_post

Co-authored-by: Chuck Rasbold <rasbold@google.com>
Reviewed-by: never, kvn

hotspot/src/share/vm/opto/loopopts.cpp

@@ -346,7 +346,10 @@ Node *PhaseIdealLoop::remix_address_expressions( Node *n ) {
 
     // Yes!  Reshape address expression!
     Node *inv_scale = new (C, 3) LShiftINode( add_invar, scale );
-    register_new_node( inv_scale, add_invar_ctrl );
+    Node *inv_scale_ctrl =
+      dom_depth(add_invar_ctrl) > dom_depth(scale_ctrl) ?
+      add_invar_ctrl : scale_ctrl;
+    register_new_node( inv_scale, inv_scale_ctrl );
     Node *var_scale = new (C, 3) LShiftINode( add_var, scale );
     register_new_node( var_scale, n_ctrl );
     Node *var_add = new (C, 3) AddINode( var_scale, inv_scale );

hotspot/test/compiler/6860469/Test.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+/**
+ * @test
+ * @bug 6860469
+ * @summary remix_address_expressions reshapes address expression with bad control
+ *
+ * @run main/othervm -Xcomp -XX:CompileOnly=Test.C Test
+ */
+
+public class Test {
+
+  private static final int H = 16;
+  private static final int F = 9;
+
+  static int[] fl = new int[1 << F];
+
+  static int C(int ll, int f) {
+    int max = -1;
+    int min = H + 1;
+
+    if (ll != 0) {
+      if (ll < min) {
+        min = ll;
+      }
+      if (ll > max) {
+        max = ll;
+      }
+    }
+
+    if (f > max) {
+      f = max;
+    }
+    if (min > f) {
+      min = f;
+    }
+
+    for (int mc = 1 >> max - f; mc <= 0; mc++) {
+      int i = mc << (32 - f);
+      fl[i] = max;
+    }
+
+    return min;
+  }
+
+  public static void main(String argv[]) {
+    C(0, 10);
+  }
+}