src/share/vm/opto/subnode.cpp

*** 204,213 ****
--- 204,221 ----
  
    // Convert "(A+X) - (B+X)" into "A - B"
    if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) )
      return new (phase->C, 3) SubINode( in1->in(1), in2->in(1) );
  
+   // Convert "(A+X) - (X+B)" into "A - B"
+   if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) )
+     return new (phase->C, 3) SubINode( in1->in(1), in2->in(2) );
+ 
+   // Convert "(X+A) - (B+X)" into "A - B"
+   if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) )
+     return new (phase->C, 3) SubINode( in1->in(2), in2->in(1) );
+ 
    // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally
    // nicer to optimize than subtract.
    if( op2 == Op_SubI && in2->outcnt() == 1) {
      Node *add1 = phase->transform( new (phase->C, 3) AddINode( in1, in2->in(2) ) );
      return new (phase->C, 3) SubINode( add1, in2->in(1) );