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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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package com.oracle.svm.core;
import org.graalvm.compiler.api.replacements.Fold;
import org.graalvm.nativeimage.ImageSingletons;
import org.graalvm.nativeimage.Isolate;
import org.graalvm.nativeimage.IsolateThread;
import org.graalvm.nativeimage.Platform;
import org.graalvm.nativeimage.Platforms;
import jdk.vm.ci.code.Register;
import jdk.vm.ci.code.RegisterValue;
import jdk.vm.ci.meta.JavaValue;
public abstract class ReservedRegisters {
@Fold
public static ReservedRegisters singleton() {
return ImageSingletons.lookup(ReservedRegisters.class);
}
protected final Register frameRegister;
protected final Register threadRegister;
protected final Register heapBaseRegister;
@Platforms(Platform.HOSTED_ONLY.class)
protected ReservedRegisters(Register frameRegister, Register threadRegisterCandidate, Register heapBaseRegisterCandidate) {
this.frameRegister = frameRegister;
this.threadRegister = SubstrateOptions.MultiThreaded.getValue() ? threadRegisterCandidate : null;
this.heapBaseRegister = SubstrateOptions.SpawnIsolates.getValue() ? heapBaseRegisterCandidate : null;
}
Returns the register used as the frame pointer.
/**
* Returns the register used as the frame pointer.
*/
public Register getFrameRegister() {
return frameRegister;
}
Returns the register that contains the current IsolateThread
; or null if no thread register is used. /**
* Returns the register that contains the current {@link IsolateThread}; or null if no thread
* register is used.
*/
public Register getThreadRegister() {
return threadRegister;
}
Returns the register holding the heap base address for compressed pointers, i.e., the current Isolate
; or null if no heap base register is used. /**
* Returns the register holding the heap base address for compressed pointers, i.e., the current
* {@link Isolate}; or null if no heap base register is used.
*/
public Register getHeapBaseRegister() {
return heapBaseRegister;
}
Returns true if the provided value is a RegisterValue
for a reserved register that is allowed to be in a frame state, i.e., for a reserved register that can be handled by deoptimization. /**
* Returns true if the provided value is a {@link RegisterValue} for a reserved register that is
* allowed to be in a frame state, i.e., for a reserved register that can be handled by
* deoptimization.
*/
public boolean isAllowedInFrameState(JavaValue value) {
if (value instanceof RegisterValue) {
Register register = ((RegisterValue) value).getRegister();
if (register.equals(threadRegister) || register.equals(heapBaseRegister)) {
return true;
}
}
return false;
}
}