1 /*
   2  * Copyright (c) 1997, 2008, 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 class Matcher;
  26 class ProjNode;
  27 
  28 //------------------------------MultiNode--------------------------------------
  29 // This class defines a MultiNode, a Node which produces many values.  The
  30 // values are wrapped up in a tuple Type, i.e. a TypeTuple.
  31 class MultiNode : public Node {
  32 public:
  33   MultiNode( uint required ) : Node(required) {
  34     init_class_id(Class_Multi);
  35   }
  36   virtual int Opcode() const;
  37   virtual const Type *bottom_type() const = 0;
  38   virtual bool       is_CFG() const { return true; }
  39   virtual uint hash() const { return NO_HASH; }  // CFG nodes do not hash
  40   virtual bool depends_only_on_test() const { return false; }
  41   virtual const RegMask &out_RegMask() const;
  42   virtual Node *match( const ProjNode *proj, const Matcher *m );
  43   virtual uint ideal_reg() const { return NotAMachineReg; }
  44   ProjNode* proj_out(uint which_proj) const; // Get a named projection
  45 
  46 };
  47 
  48 //------------------------------ProjNode---------------------------------------
  49 // This class defines a Projection node.  Projections project a single element
  50 // out of a tuple (or Signature) type.  Only MultiNodes produce TypeTuple
  51 // results.
  52 class ProjNode : public Node {
  53 protected:
  54   virtual uint hash() const;
  55   virtual uint cmp( const Node &n ) const;
  56   virtual uint size_of() const;
  57   void check_con() const;       // Called from constructor.
  58 
  59 public:
  60   ProjNode( Node *src, uint con, bool io_use = false )
  61     : Node( src ), _con(con), _is_io_use(io_use)
  62   {
  63     init_class_id(Class_Proj);
  64     // Optimistic setting. Need additional checks in Node::is_dead_loop_safe().
  65     if (con != TypeFunc::Memory || src->is_Start())
  66       init_flags(Flag_is_dead_loop_safe);
  67     debug_only(check_con());
  68   }
  69   const uint _con;              // The field in the tuple we are projecting
  70   const bool _is_io_use;        // Used to distinguish between the projections
  71                                 // used on the control and io paths from a macro node
  72   virtual int Opcode() const;
  73   virtual bool      is_CFG() const;
  74   virtual bool depends_only_on_test() const { return false; }
  75   virtual const Type *bottom_type() const;
  76   virtual const TypePtr *adr_type() const;
  77   virtual bool pinned() const;
  78   virtual const Type *Value( PhaseTransform *phase ) const;
  79   virtual uint ideal_reg() const;
  80   virtual const RegMask &out_RegMask() const;
  81 #ifndef PRODUCT
  82   virtual void dump_spec(outputStream *st) const;
  83 #endif
  84 };