1 /*
   2  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "opto/narrowptrnode.hpp"
  27 #include "opto/phaseX.hpp"
  28 
  29 Node* DecodeNNode::Identity(PhaseTransform* phase) {
  30     const Type *t = phase->type( in(1) );
  31     if( t == Type::TOP ) return in(1);
  32 
  33     if (in(1)->is_EncodeP()) {
  34         // (DecodeN (EncodeP p)) -> p
  35         return in(1)->in(1);
  36     }
  37     return this;
  38 }
  39 
  40 const Type *DecodeNNode::Value( PhaseTransform *phase ) const {
  41     const Type *t = phase->type( in(1) );
  42     if (t == Type::TOP) return Type::TOP;
  43     if (t == TypeNarrowOop::NULL_PTR) return TypePtr::NULL_PTR;
  44 
  45     assert(t->isa_narrowoop(), "only  narrowoop here");
  46     return t->make_ptr();
  47 }
  48 
  49 Node* EncodePNode::Identity(PhaseTransform* phase) {
  50     const Type *t = phase->type( in(1) );
  51     if( t == Type::TOP ) return in(1);
  52 
  53     if (in(1)->is_DecodeN()) {
  54         // (EncodeP (DecodeN p)) -> p
  55         return in(1)->in(1);
  56     }
  57     return this;
  58 }
  59 
  60 const Type *EncodePNode::Value( PhaseTransform *phase ) const {
  61     const Type *t = phase->type( in(1) );
  62     if (t == Type::TOP) return Type::TOP;
  63     if (t == TypePtr::NULL_PTR) return TypeNarrowOop::NULL_PTR;
  64 
  65     assert(t->isa_oop_ptr(), "only oopptr here");
  66     return t->make_narrowoop();
  67 }
  68 
  69 
  70 Node *EncodeNarrowPtrNode::Ideal_DU_postCCP( PhaseCCP *ccp ) {
  71     return MemNode::Ideal_common_DU_postCCP(ccp, this, in(1));
  72 }
  73 
  74 Node* DecodeNKlassNode::Identity(PhaseTransform* phase) {
  75     const Type *t = phase->type( in(1) );
  76     if( t == Type::TOP ) return in(1);
  77 
  78     if (in(1)->is_EncodePKlass()) {
  79         // (DecodeNKlass (EncodePKlass p)) -> p
  80         return in(1)->in(1);
  81     }
  82     return this;
  83 }
  84 
  85 const Type *DecodeNKlassNode::Value( PhaseTransform *phase ) const {
  86     const Type *t = phase->type( in(1) );
  87     if (t == Type::TOP) return Type::TOP;
  88     assert(t != TypeNarrowKlass::NULL_PTR, "null klass?");
  89 
  90     assert(t->isa_narrowklass(), "only narrow klass ptr here");
  91     return t->make_ptr();
  92 }
  93 
  94 Node* EncodePKlassNode::Identity(PhaseTransform* phase) {
  95     const Type *t = phase->type( in(1) );
  96     if( t == Type::TOP ) return in(1);
  97 
  98     if (in(1)->is_DecodeNKlass()) {
  99         // (EncodePKlass (DecodeNKlass p)) -> p
 100         return in(1)->in(1);
 101     }
 102     return this;
 103 }
 104 
 105 const Type *EncodePKlassNode::Value( PhaseTransform *phase ) const {
 106     const Type *t = phase->type( in(1) );
 107     if (t == Type::TOP) return Type::TOP;
 108     assert (t != TypePtr::NULL_PTR, "null klass?");
 109 
 110     assert(UseCompressedClassPointers && t->isa_klassptr(), "only klass ptr here");
 111     return t->make_narrowklass();
 112 }
 113