src/share/vm/opto/connode.cpp

*** 561,570 ****
--- 561,590 ----
      return in(1)->in(1);
    }
    return this;
  }
  
+ const Type *DecodeNNode::Value( PhaseTransform *phase ) const {
+   if (phase->type( in(1) ) == TypeNarrowOop::NULL_PTR) {
+     return TypePtr::NULL_PTR;
+   }
+   return bottom_type();
+ }
+ 
+ Node* DecodeNNode::decode(PhaseGVN* phase, Node* value) {
+   if (value->Opcode() == Op_EncodeP) {
+     // (DecodeN (EncodeP p)) -> p
+     return value->in(1);
+   }
+   const Type* newtype = value->bottom_type();
+   if (newtype == TypeNarrowOop::NULL_PTR) {
+     return phase->transform(new (phase->C, 1) ConPNode(TypePtr::NULL_PTR));
+   } else {
+     return phase->transform(new (phase->C, 2) DecodeNNode(value, newtype->is_narrowoop()->make_oopptr()));
+   }
+ }
+ 
  Node* EncodePNode::Identity(PhaseTransform* phase) {
    const Type *t = phase->type( in(1) );
    if( t == Type::TOP ) return in(1);
  
    if (in(1)->Opcode() == Op_DecodeN) {
*** 572,589 ****
      return in(1)->in(1);
    }
    return this;
  }
  
  
  Node* EncodePNode::encode(PhaseGVN* phase, Node* value) {
    const Type* newtype = value->bottom_type();
    if (newtype == TypePtr::NULL_PTR) {
      return phase->transform(new (phase->C, 1) ConNNode(TypeNarrowOop::NULL_PTR));
    } else {
!     return phase->transform(new (phase->C, 2) EncodePNode(value,
!                                                           newtype->is_oopptr()->make_narrowoop()));
    }
  }
  
  
  //=============================================================================
--- 592,621 ----
      return in(1)->in(1);
    }
    return this;
  }
  
+ const Type *EncodePNode::Value( PhaseTransform *phase ) const {
+   if (phase->type( in(1) ) == TypePtr::NULL_PTR) {
+     return TypeNarrowOop::NULL_PTR;
+   }
+   return bottom_type();
+ }
  
  Node* EncodePNode::encode(PhaseGVN* phase, Node* value) {
+   if (value->Opcode() == Op_DecodeN) {
+     // (EncodeP (DecodeN p)) -> p
+     return value->in(1);
+   }
    const Type* newtype = value->bottom_type();
    if (newtype == TypePtr::NULL_PTR) {
      return phase->transform(new (phase->C, 1) ConNNode(TypeNarrowOop::NULL_PTR));
+   } else if (newtype->isa_oopptr()) {
+     return phase->transform(new (phase->C, 2) EncodePNode(value, newtype->is_oopptr()->make_narrowoop()));
    } else {
!     ShouldNotReachHere();
!     return NULL; // to make C++ compiler happy.
    }
  }
  
  
  //=============================================================================