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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package sun.jvm.hotspot.code;

import java.io.*;
import java.util.*;
import sun.jvm.hotspot.debugger.*;
import sun.jvm.hotspot.runtime.*;
import sun.jvm.hotspot.types.*;
import sun.jvm.hotspot.utilities.Observable;
import sun.jvm.hotspot.utilities.Observer;

PcDescs map a physical PC (given as offset from start of nmethod) to the corresponding source scope and byte code index.
/** PcDescs map a physical PC (given as offset from start of nmethod) to the corresponding source scope and byte code index. */
public class PCDesc extends VMObject { private static CIntegerField pcOffsetField; private static CIntegerField scopeDecodeOffsetField; private static CIntegerField objDecodeOffsetField; private static CIntegerField pcFlagsField; private static int reexecuteMask; private static int isMethodHandleInvokeMask; private static int returnOopMask; static { VM.registerVMInitializedObserver(new Observer() { public void update(Observable o, Object data) { initialize(VM.getVM().getTypeDataBase()); } }); } private static void initialize(TypeDataBase db) { Type type = db.lookupType("PcDesc"); pcOffsetField = type.getCIntegerField("_pc_offset"); scopeDecodeOffsetField = type.getCIntegerField("_scope_decode_offset"); objDecodeOffsetField = type.getCIntegerField("_obj_decode_offset"); pcFlagsField = type.getCIntegerField("_flags"); reexecuteMask = db.lookupIntConstant("PcDesc::PCDESC_reexecute"); isMethodHandleInvokeMask = db.lookupIntConstant("PcDesc::PCDESC_is_method_handle_invoke"); returnOopMask = db.lookupIntConstant("PcDesc::PCDESC_return_oop"); } public PCDesc(Address addr) { super(addr); } // FIXME: add additional constructor probably needed for ScopeDesc::sender() public int getPCOffset() { return (int) pcOffsetField.getValue(addr); } public int getScopeDecodeOffset() { return ((int) scopeDecodeOffsetField.getValue(addr)); } public int getObjDecodeOffset() { return ((int) objDecodeOffsetField.getValue(addr)); } public Address getRealPC(NMethod code) { return code.codeBegin().addOffsetTo(getPCOffset()); } public boolean getReexecute() { int flags = (int)pcFlagsField.getValue(addr); return (flags & reexecuteMask) != 0; } public boolean isMethodHandleInvoke() { int flags = (int)pcFlagsField.getValue(addr); return (flags & isMethodHandleInvokeMask) != 0; } public void print(NMethod code) { printOn(System.out, code); } public void printOn(PrintStream tty, NMethod code) { tty.println("PCDesc(" + getRealPC(code) + "):"); for (ScopeDesc sd = code.getScopeDescAt(getRealPC(code)); sd != null; sd = sd.sender()) { tty.print(" "); sd.getMethod().printValueOn(tty); tty.print(" @" + sd.getBCI()); tty.print(" reexecute=" + sd.getReexecute()); tty.println(); } } }