src/share/vm/opto/mulnode.cpp

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   1 /*
   2  * Copyright (c) 1997, 2009, 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 // Portions of code courtesy of Clifford Click







  26 
  27 #include "incls/_precompiled.incl"
  28 #include "incls/_mulnode.cpp.incl"
  29 
  30 
  31 //=============================================================================
  32 //------------------------------hash-------------------------------------------
  33 // Hash function over MulNodes.  Needs to be commutative; i.e., I swap
  34 // (commute) inputs to MulNodes willy-nilly so the hash function must return
  35 // the same value in the presence of edge swapping.
  36 uint MulNode::hash() const {
  37   return (uintptr_t)in(1) + (uintptr_t)in(2) + Opcode();
  38 }
  39 
  40 //------------------------------Identity---------------------------------------
  41 // Multiplying a one preserves the other argument
  42 Node *MulNode::Identity( PhaseTransform *phase ) {
  43   register const Type *one = mul_id();  // The multiplicative identity
  44   if( phase->type( in(1) )->higher_equal( one ) ) return in(2);
  45   if( phase->type( in(2) )->higher_equal( one ) ) return in(1);
  46 
  47   return this;
  48 }


   1 /*
   2  * Copyright (c) 1997, 2010, 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 "memory/allocation.inline.hpp"
  27 #include "opto/addnode.hpp"
  28 #include "opto/connode.hpp"
  29 #include "opto/memnode.hpp"
  30 #include "opto/mulnode.hpp"
  31 #include "opto/phaseX.hpp"
  32 #include "opto/subnode.hpp"
  33 
  34 // Portions of code courtesy of Clifford Click

  35 
  36 
  37 //=============================================================================
  38 //------------------------------hash-------------------------------------------
  39 // Hash function over MulNodes.  Needs to be commutative; i.e., I swap
  40 // (commute) inputs to MulNodes willy-nilly so the hash function must return
  41 // the same value in the presence of edge swapping.
  42 uint MulNode::hash() const {
  43   return (uintptr_t)in(1) + (uintptr_t)in(2) + Opcode();
  44 }
  45 
  46 //------------------------------Identity---------------------------------------
  47 // Multiplying a one preserves the other argument
  48 Node *MulNode::Identity( PhaseTransform *phase ) {
  49   register const Type *one = mul_id();  // The multiplicative identity
  50   if( phase->type( in(1) )->higher_equal( one ) ) return in(2);
  51   if( phase->type( in(2) )->higher_equal( one ) ) return in(1);
  52 
  53   return this;
  54 }