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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package sun.jvm.hotspot.code;

import java.io.*;
import java.util.*;

import sun.jvm.hotspot.debugger.*;
import sun.jvm.hotspot.oops.*;
import sun.jvm.hotspot.runtime.*;
import sun.jvm.hotspot.utilities.*;

ScopeDescs contain the information that makes source-level debugging of nmethods possible; each scopeDesc describes a method activation
/** ScopeDescs contain the information that makes source-level debugging of nmethods possible; each scopeDesc describes a method activation */
public class ScopeDesc {
NMethod information
/** NMethod information */
private NMethod code; private Method method; private int bci; private boolean reexecute;
Decoding offsets
/** Decoding offsets */
private int decodeOffset; private int senderDecodeOffset; private int localsDecodeOffset; private int expressionsDecodeOffset; private int monitorsDecodeOffset;
Scalar replaced bjects pool
/** Scalar replaced bjects pool */
private List<ObjectValue> objects; private ScopeDesc(NMethod code, int decodeOffset, List<ObjectValue> objects, boolean reexecute) { this.code = code; this.decodeOffset = decodeOffset; this.objects = objects; this.reexecute = reexecute; // Decode header DebugInfoReadStream stream = streamAt(decodeOffset); senderDecodeOffset = stream.readInt(); method = stream.readMethod(); bci = stream.readBCI(); // Decode offsets for body and sender localsDecodeOffset = stream.readInt(); expressionsDecodeOffset = stream.readInt(); monitorsDecodeOffset = stream.readInt(); } public ScopeDesc(NMethod code, int decodeOffset, int objectDecodeOffset, boolean reexecute) { this.code = code; this.decodeOffset = decodeOffset; this.objects = decodeObjectValues(objectDecodeOffset); this.reexecute = reexecute; // Decode header DebugInfoReadStream stream = streamAt(decodeOffset); senderDecodeOffset = stream.readInt(); method = stream.readMethod(); bci = stream.readBCI(); // Decode offsets for body and sender localsDecodeOffset = stream.readInt(); expressionsDecodeOffset = stream.readInt(); monitorsDecodeOffset = stream.readInt(); } public NMethod getNMethod() { return code; } public Method getMethod() { return method; } public int getBCI() { return bci; } public boolean getReexecute() { return reexecute;}
Returns a List<ScopeValue>
/** Returns a List&lt;ScopeValue&gt; */
public List<ScopeValue> getLocals() { return decodeScopeValues(localsDecodeOffset); }
Returns a List<ScopeValue>
/** Returns a List&lt;ScopeValue&gt; */
public List<ScopeValue> getExpressions() { return decodeScopeValues(expressionsDecodeOffset); }
Returns a List<MonitorValue>
/** Returns a List&lt;MonitorValue&gt; */
public List<MonitorValue> getMonitors() { return decodeMonitorValues(monitorsDecodeOffset); }
Returns a List<ObjectValue>
/** Returns a List&lt;ObjectValue&gt; */
public List<ObjectValue> getObjects() { return objects; }
Stack walking. Returns null if this is the outermost scope.
/** Stack walking. Returns null if this is the outermost scope. */
public ScopeDesc sender() { if (isTop()) { return null; } return new ScopeDesc(code, senderDecodeOffset, objects, false); }
Returns where the scope was decoded
/** Returns where the scope was decoded */
public int getDecodeOffset() { return decodeOffset; }
Tells whether sender() returns null
/** Tells whether sender() returns null */
public boolean isTop() { return (senderDecodeOffset == DebugInformationRecorder.SERIALIZED_NULL); } public boolean equals(Object arg) { if (arg == null) { return false; } if (!(arg instanceof ScopeDesc)) { return false; } ScopeDesc sd = (ScopeDesc) arg; return (sd.method.equals(method) && (sd.bci == bci)); } public void printValue() { printValueOn(System.out); } public void printValueOn(PrintStream tty) { tty.print("ScopeDesc for "); method.printValueOn(tty); tty.print(" @bci " + bci); tty.println(" reexecute=" + reexecute); } // FIXME: add more accessors //-------------------------------------------------------------------------------- // Internals only below this point // private DebugInfoReadStream streamAt(int decodeOffset) { return new DebugInfoReadStream(code, decodeOffset, objects); }
Returns a List<ScopeValue> or null if no values were present
/** Returns a List&lt;ScopeValue&gt; or null if no values were present */
private List<ScopeValue> decodeScopeValues(int decodeOffset) { if (decodeOffset == DebugInformationRecorder.SERIALIZED_NULL) { return null; } DebugInfoReadStream stream = streamAt(decodeOffset); int length = stream.readInt(); List<ScopeValue> res = new ArrayList<>(length); for (int i = 0; i < length; i++) { res.add(ScopeValue.readFrom(stream)); } return res; }
Returns a List<MonitorValue> or null if no values were present
/** Returns a List&lt;MonitorValue&gt; or null if no values were present */
private List<MonitorValue> decodeMonitorValues(int decodeOffset) { if (decodeOffset == DebugInformationRecorder.SERIALIZED_NULL) { return null; } DebugInfoReadStream stream = streamAt(decodeOffset); int length = stream.readInt(); List<MonitorValue> res = new ArrayList<>(length); for (int i = 0; i < length; i++) { res.add(new MonitorValue(stream)); } return res; }
Returns a List<ObjectValue> or null if no values were present
/** Returns a List&lt;ObjectValue&gt; or null if no values were present */
private List<ObjectValue> decodeObjectValues(int decodeOffset) { if (decodeOffset == DebugInformationRecorder.SERIALIZED_NULL) { return null; } List<ObjectValue> res = new ArrayList<>(); DebugInfoReadStream stream = new DebugInfoReadStream(code, decodeOffset, res); int length = stream.readInt(); for (int i = 0; i < length; i++) { // Objects values are pushed to 'res' array during read so that // object's fields could reference it (OBJECT_ID_CODE). ScopeValue.readFrom(stream); // res.add(ScopeValue.readFrom(stream)); } Assert.that(res.size() == length, "inconsistent debug information"); return res; } }