1 /*
   2  * Copyright (c) 2014, 2015, 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 package org.graalvm.compiler.lir.constopt;
  24 
  25 import java.util.ArrayList;
  26 import java.util.List;
  27 import java.util.function.Consumer;
  28 
  29 import org.graalvm.compiler.core.common.cfg.AbstractBlockBase;
  30 import org.graalvm.compiler.lir.LIRInstruction;
  31 import org.graalvm.compiler.lir.StandardOp.LoadConstantOp;
  32 import org.graalvm.compiler.lir.Variable;
  33 
  34 import jdk.vm.ci.meta.Constant;
  35 import jdk.vm.ci.meta.Value;
  36 
  37 /**
  38  * Represents def-use tree of a constant.
  39  */
  40 class DefUseTree {
  41     private final LoadConstantOp instruction;
  42     private final AbstractBlockBase<?> block;
  43     private final List<UseEntry> uses;
  44 
  45     DefUseTree(LIRInstruction instruction, AbstractBlockBase<?> block) {
  46         assert instruction instanceof LoadConstantOp : "Not a LoadConstantOp: " + instruction;
  47         this.instruction = (LoadConstantOp) instruction;
  48         this.block = block;
  49         this.uses = new ArrayList<>();
  50     }
  51 
  52     public Variable getVariable() {
  53         return (Variable) instruction.getResult();
  54     }
  55 
  56     public Constant getConstant() {
  57         return instruction.getConstant();
  58     }
  59 
  60     public LIRInstruction getInstruction() {
  61         return (LIRInstruction) instruction;
  62     }
  63 
  64     public AbstractBlockBase<?> getBlock() {
  65         return block;
  66     }
  67 
  68     @Override
  69     public String toString() {
  70         return "DefUseTree [" + instruction + "|" + block + "," + uses + "]";
  71     }
  72 
  73     public void addUsage(AbstractBlockBase<?> b, LIRInstruction inst, Value value) {
  74         uses.add(new UseEntry(b, inst, value));
  75     }
  76 
  77     public int usageCount() {
  78         return uses.size();
  79     }
  80 
  81     public void forEach(Consumer<? super UseEntry> action) {
  82         uses.forEach(action);
  83     }
  84 
  85 }