1 /*
   2  * Copyright (c) 2013, 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;
  24 
  25 import java.lang.annotation.ElementType;
  26 import java.lang.annotation.Retention;
  27 import java.lang.annotation.RetentionPolicy;
  28 import java.lang.annotation.Target;
  29 import java.util.EnumSet;
  30 
  31 import org.graalvm.compiler.debug.Debug;
  32 import org.graalvm.compiler.debug.DebugCounter;
  33 import org.graalvm.compiler.lir.LIRInstruction.OperandFlag;
  34 import org.graalvm.compiler.lir.LIRInstruction.OperandMode;
  35 
  36 import jdk.vm.ci.meta.Value;
  37 import jdk.vm.ci.meta.ValueKind;
  38 
  39 /**
  40  * Base class to represent values that need to be stored in more than one register. This is mainly
  41  * intended to support addresses and not general arbitrary nesting of composite values. Because of
  42  * the possibility of sharing of CompositeValues they should be immutable.
  43  */
  44 public abstract class CompositeValue extends Value {
  45 
  46     @Retention(RetentionPolicy.RUNTIME)
  47     @Target(ElementType.FIELD)
  48     public static @interface Component {
  49 
  50         OperandFlag[] value() default OperandFlag.REG;
  51     }
  52 
  53     private static final DebugCounter COMPOSITE_VALUE_COUNT = Debug.counter("CompositeValues");
  54 
  55     public CompositeValue(ValueKind<?> kind) {
  56         super(kind);
  57         COMPOSITE_VALUE_COUNT.increment();
  58         assert CompositeValueClass.get(getClass()) != null;
  59     }
  60 
  61     /**
  62      * Invoke {@code proc} on each {@link Value} element of this {@link CompositeValue}. If
  63      * {@code proc} replaces any value then a new CompositeValue should be returned.
  64      *
  65      * @param inst
  66      * @param mode
  67      * @param proc
  68      * @return the original CompositeValue or a copy with any modified values
  69      */
  70     public abstract CompositeValue forEachComponent(LIRInstruction inst, OperandMode mode, InstructionValueProcedure proc);
  71 
  72     /**
  73      * A helper method to visit {@link Value}[] ensuring that a copy of the array is made if it's
  74      * needed.
  75      *
  76      * @param inst
  77      * @param values
  78      * @param mode
  79      * @param proc
  80      * @param flags
  81      * @return the original {@code values} array or a copy if values changed
  82      */
  83     protected Value[] visitValueArray(LIRInstruction inst, Value[] values, OperandMode mode, InstructionValueProcedure proc, EnumSet<OperandFlag> flags) {
  84         Value[] newValues = null;
  85         for (int i = 0; i < values.length; i++) {
  86             Value value = values[i];
  87             Value newValue = proc.doValue(inst, value, mode, flags);
  88             if (!value.identityEquals(newValue)) {
  89                 if (newValues == null) {
  90                     newValues = values.clone();
  91                 }
  92                 newValues[i] = value;
  93             }
  94         }
  95         return newValues != null ? newValues : values;
  96     }
  97 
  98     protected abstract void visitEachComponent(LIRInstruction inst, OperandMode mode, InstructionValueConsumer proc);
  99 
 100     @Override
 101     public String toString() {
 102         return CompositeValueClass.format(this);
 103     }
 104 
 105     @Override
 106     public int hashCode() {
 107         return 53 * super.hashCode();
 108     }
 109 
 110     @Override
 111     public boolean equals(Object obj) {
 112         if (obj instanceof CompositeValue) {
 113             CompositeValue other = (CompositeValue) obj;
 114             return super.equals(other);
 115         }
 116         return false;
 117     }
 118 }