/*
* This file is part of the Jikes RVM project (http://jikesrvm.org).
*
* This file is licensed to You under the Eclipse Public License (EPL);
* You may not use this file except in compliance with the License. You
* may obtain a copy of the License at
*
* http://www.opensource.org/licenses/eclipse-1.0.php
*
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership.
*/
package org.jikesrvm.ia32;
import static org.jikesrvm.ia32.BaselineConstants.T0_SAVE_OFFSET;
import static org.jikesrvm.ia32.RegisterConstants.NUM_PARAMETER_GPRS;
import org.jikesrvm.VM;
import org.jikesrvm.runtime.Magic;
import org.vmmagic.pragma.NoInline;
import org.vmmagic.pragma.Uninterruptible;
import org.vmmagic.unboxed.Address;
/**
* Machine specific helper functions for dynamic linking.
*/
@Uninterruptible
public abstract class DynamicLinkerHelper {
/**
* Reach up two stack frames into a frame that is compiled
* with the DynamicBridge register protocol and grab
* the receiver object of the invoke.
* <p>
* NOTE: assumes that caller has disabled GC.
*
* @return the receiver object for the method invocation
*/
@NoInline
public static Object getReceiverObject() {
Address callingFrame = Magic.getCallerFramePointer(Magic.getFramePointer());
callingFrame = Magic.getCallerFramePointer(callingFrame);
Address location = Address.zero();
if (0 < NUM_PARAMETER_GPRS) {
location = callingFrame.plus(T0_SAVE_OFFSET).loadAddress();
} else {
VM.sysFail("DynamicLinerHelper: assumes at least one param passed in registers");
}
return Magic.addressAsObject(location);
}
}