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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* 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).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package org.graalvm.compiler.hotspot.replacements;
import org.graalvm.compiler.core.common.type.StampPair;
import org.graalvm.compiler.debug.GraalError;
import org.graalvm.compiler.graph.Node;
import org.graalvm.compiler.graph.NodeClass;
import org.graalvm.compiler.graph.spi.Canonicalizable;
import org.graalvm.compiler.graph.spi.CanonicalizerTool;
import org.graalvm.compiler.nodeinfo.NodeInfo;
import org.graalvm.compiler.nodes.CallTargetNode.InvokeKind;
import org.graalvm.compiler.nodes.ConstantNode;
import org.graalvm.compiler.nodes.FrameState;
import org.graalvm.compiler.nodes.InvokeNode;
import org.graalvm.compiler.nodes.ValueNode;
import org.graalvm.compiler.nodes.spi.Lowerable;
import org.graalvm.compiler.nodes.spi.LoweringTool;
import org.graalvm.compiler.replacements.nodes.MacroStateSplitNode;
import jdk.vm.ci.hotspot.HotSpotResolvedJavaMethod;
import jdk.vm.ci.hotspot.HotSpotResolvedObjectType;
import jdk.vm.ci.meta.ConstantReflectionProvider;
import jdk.vm.ci.meta.MetaAccessProvider;
import jdk.vm.ci.meta.ResolvedJavaMethod;
@NodeInfo
public final class ReflectionGetCallerClassNode extends MacroStateSplitNode implements Canonicalizable, Lowerable {
public static final NodeClass<ReflectionGetCallerClassNode> TYPE = NodeClass.create(ReflectionGetCallerClassNode.class);
public ReflectionGetCallerClassNode(InvokeKind invokeKind, ResolvedJavaMethod targetMethod, int bci, StampPair returnStamp, ValueNode... arguments) {
super(TYPE, invokeKind, targetMethod, bci, returnStamp, arguments);
}
@Override
public Node canonical(CanonicalizerTool tool) {
ConstantNode callerClassNode = getCallerClassNode(tool.getMetaAccess(), tool.getConstantReflection());
if (callerClassNode != null) {
return callerClassNode;
}
return this;
}
@Override
public void lower(LoweringTool tool) {
ConstantNode callerClassNode = getCallerClassNode(tool.getMetaAccess(), tool.getConstantReflection());
if (callerClassNode != null) {
graph().replaceFixedWithFloating(this, graph().addOrUniqueWithInputs(callerClassNode));
} else {
InvokeNode invoke = createInvoke();
graph().replaceFixedWithFixed(this, invoke);
invoke.lower(tool);
}
}
/**
* If inlining is deep enough this method returns a {@link ConstantNode} of the caller class by
* walking the stack.
*
* @param metaAccess
* @return ConstantNode of the caller class, or null
*/
private ConstantNode getCallerClassNode(MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection) {
// Walk back up the frame states to find the caller at the required depth.
FrameState state = stateAfter();
// Cf. JVM_GetCallerClass
// NOTE: Start the loop at depth 1 because the current frame state does
// not include the Reflection.getCallerClass() frame.
for (int n = 1; state != null; state = state.outerFrameState(), n++) {
HotSpotResolvedJavaMethod method = (HotSpotResolvedJavaMethod) state.getMethod();
switch (n) {
case 0:
throw GraalError.shouldNotReachHere("current frame state does not include the Reflection.getCallerClass frame");
case 1:
// Frame 0 and 1 must be caller sensitive (see JVM_GetCallerClass).
if (!method.isCallerSensitive()) {
return null; // bail-out; let JVM_GetCallerClass do the work
}
break;
default:
if (!method.ignoredBySecurityStackWalk()) {
// We have reached the desired frame; return the holder class.
HotSpotResolvedObjectType callerClass = method.getDeclaringClass();
return ConstantNode.forConstant(constantReflection.asJavaClass(callerClass), metaAccess);
}
break;
}
}
return null; // bail-out; let JVM_GetCallerClass do the work
}
}