*** old/src/hotspot/share/opto/mathexactnode.cpp	Thu Jan 11 10:28:54 2018
--- new/src/hotspot/share/opto/mathexactnode.cpp	Thu Jan 11 10:28:54 2018

*** 1,7 ****
--- 1,7 ----
  /*
!  * Copyright (c) 2013, 2014, Oracle and/or its affiliates. All rights reserved.
!  * Copyright (c) 2013, 2018, Oracle and/or its affiliates. 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.

*** 115,128 ****
--- 115,138 ----
  
  bool OverflowSubLNode::will_overflow(jlong v1, jlong v2) const {
    return SubHelper<OverflowSubLNode>::will_overflow(v1, v2);
  }
  
+ static jlong negate_jlong(jlong val) {
+   if (val == min_jlong) {
+     return min_jlong;
+   }
+   return -val;
+ }
+ 
  bool OverflowMulLNode::will_overflow(jlong val1, jlong val2) const {
!     jlong result = val1 * val2;
!     jlong ax = (val1 < 0 ? -val1 : val1);
!     jlong ay = (val2 < 0 ? -val2 : val2);
!     julong v1 = (julong) val1;
!     julong v2 = (julong) val2;
!     julong tmp = v1 * v2;
+     jlong result = (jlong) tmp;
+     jlong ax = (val1 < 0 ? negate_jlong(val1) : val1);
+     jlong ay = (val2 < 0 ? negate_jlong(val2) : val2);
  
      bool overflow = false;
      if ((ax | ay) & CONST64(0xFFFFFFFF00000000)) {
        // potential overflow if any bit in upper 32 bits are set
        if ((val1 == min_jlong && val2 == -1) || (val2 == min_jlong && val1 == -1)) {