001    /*
002     *  This file is part of the Jikes RVM project (http://jikesrvm.org).
003     *
004     *  This file is licensed to You under the Eclipse Public License (EPL);
005     *  You may not use this file except in compliance with the License. You
006     *  may obtain a copy of the License at
007     *
008     *      http://www.opensource.org/licenses/eclipse-1.0.php
009     *
010     *  See the COPYRIGHT.txt file distributed with this work for information
011     *  regarding copyright ownership.
012     */
013    package org.jikesrvm.osr.ia32;
014    
015    import org.jikesrvm.ArchitectureSpecific;
016    import org.jikesrvm.VM;
017    import org.jikesrvm.ia32.BaselineConstants;
018    import org.jikesrvm.runtime.Magic;
019    import org.jikesrvm.scheduler.RVMThread;
020    import org.vmmagic.pragma.NoInline;
021    import org.vmmagic.pragma.Uninterruptible;
022    import org.vmmagic.unboxed.Address;
023    import org.vmmagic.unboxed.Offset;
024    
025    /**
026     * A class helps schedule OSRed method, it is called right after thread switch
027     * and highly depends on the calling convention. It should not be interrupted
028     * because it deals with row instruction address.
029     */
030    @Uninterruptible
031    public abstract class PostThreadSwitch implements BaselineConstants {
032    
033      /**
034       * This method must not be inlined to keep the correctness
035       * This method is called at the end of threadSwitch, the caller
036       * is threadSwitchFrom<...>
037       */
038      @NoInline
039      public static void postProcess(RVMThread myThread) {
040    
041        /* We need to generate thread specific code and install new code.
042        * We have to make sure that no GC happens from here and before
043        * the new code get executed.
044        */
045        // add branch instruction from CTR.
046        ArchitectureSpecific.CodeArray bridge = myThread.bridgeInstructions;
047    
048        Address bridgeaddr = Magic.objectAsAddress(bridge);
049    
050        if (VM.TraceOnStackReplacement) {
051          VM.sysWrite("osr post processing\n");
052        }
053    
054        Offset offset = myThread.tsFPOffset.plus(STACKFRAME_RETURN_ADDRESS_OFFSET);
055        Magic.objectAsAddress(myThread.getStack()).store(bridgeaddr, offset);
056    
057        myThread.tsFPOffset = Offset.zero();
058    
059        myThread.isWaitingForOsr = false;
060        myThread.bridgeInstructions = null;
061    
062        // no GC should happen until the glue code gets executed.
063      }
064    }