1693 
1694 
1695 static Node* extract_obj_from_klass_load(PhaseGVN* gvn, Node* n) {
1696   Node* ldk;
1697   if (n->is_DecodeNKlass()) {
1698     if (n->in(1)->Opcode() != Op_LoadNKlass) {
1699       return nullptr;
1700     } else {
1701       ldk = n->in(1);
1702     }
1703   } else if (n->Opcode() != Op_LoadKlass) {
1704     return nullptr;
1705   } else {
1706     ldk = n;
1707   }
1708   assert(ldk != nullptr && ldk->is_Load(), "should have found a LoadKlass or LoadNKlass node");
1709 
1710   Node* adr = ldk->in(MemNode::Address);
1711   intptr_t off = 0;
1712   Node* obj = AddPNode::Ideal_base_and_offset(adr, gvn, off);
1713   if (obj == nullptr || off != oopDesc::klass_offset_in_bytes()) // loading oopDesc::_klass?
1714     return nullptr;
1715   const TypePtr* tp = gvn->type(obj)->is_ptr();
1716   if (tp == nullptr || !(tp->isa_instptr() || tp->isa_aryptr())) // is obj a Java object ptr?
1717     return nullptr;
1718 
1719   return obj;
1720 }
1721 
1722 void Parse::sharpen_type_after_if(BoolTest::mask btest,
1723                                   Node* con, const Type* tcon,
1724                                   Node* val, const Type* tval) {
1725   // Look for opportunities to sharpen the type of a node
1726   // whose klass is compared with a constant klass.
1727   if (btest == BoolTest::eq && tcon->isa_klassptr()) {
1728     Node* obj = extract_obj_from_klass_load(&_gvn, val);
1729     const TypeOopPtr* con_type = tcon->isa_klassptr()->as_instance_type();
1730     if (obj != nullptr && (con_type->isa_instptr() || con_type->isa_aryptr())) {
1731        // Found:
1732        //   Bool(CmpP(LoadKlass(obj._klass), ConP(Foo.klass)), [eq])
1733        // or the narrowOop equivalent.

1693 
1694 
1695 static Node* extract_obj_from_klass_load(PhaseGVN* gvn, Node* n) {
1696   Node* ldk;
1697   if (n->is_DecodeNKlass()) {
1698     if (n->in(1)->Opcode() != Op_LoadNKlass) {
1699       return nullptr;
1700     } else {
1701       ldk = n->in(1);
1702     }
1703   } else if (n->Opcode() != Op_LoadKlass) {
1704     return nullptr;
1705   } else {
1706     ldk = n;
1707   }
1708   assert(ldk != nullptr && ldk->is_Load(), "should have found a LoadKlass or LoadNKlass node");
1709 
1710   Node* adr = ldk->in(MemNode::Address);
1711   intptr_t off = 0;
1712   Node* obj = AddPNode::Ideal_base_and_offset(adr, gvn, off);
1713   if (obj == nullptr || off != Type::klass_offset()) // loading oopDesc::_klass?
1714     return nullptr;
1715   const TypePtr* tp = gvn->type(obj)->is_ptr();
1716   if (tp == nullptr || !(tp->isa_instptr() || tp->isa_aryptr())) // is obj a Java object ptr?
1717     return nullptr;
1718 
1719   return obj;
1720 }
1721 
1722 void Parse::sharpen_type_after_if(BoolTest::mask btest,
1723                                   Node* con, const Type* tcon,
1724                                   Node* val, const Type* tval) {
1725   // Look for opportunities to sharpen the type of a node
1726   // whose klass is compared with a constant klass.
1727   if (btest == BoolTest::eq && tcon->isa_klassptr()) {
1728     Node* obj = extract_obj_from_klass_load(&_gvn, val);
1729     const TypeOopPtr* con_type = tcon->isa_klassptr()->as_instance_type();
1730     if (obj != nullptr && (con_type->isa_instptr() || con_type->isa_aryptr())) {
1731        // Found:
1732        //   Bool(CmpP(LoadKlass(obj._klass), ConP(Foo.klass)), [eq])
1733        // or the narrowOop equivalent.