src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.hotspot/src/org/graalvm/compiler/hotspot/stubs/ForeignCallStub.java
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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
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* 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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* 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.stubs;
import static jdk.vm.ci.code.BytecodeFrame.UNKNOWN_BCI;
import static jdk.vm.ci.hotspot.HotSpotCallingConventionType.JavaCall;
import static jdk.vm.ci.hotspot.HotSpotCallingConventionType.JavaCallee;
import static jdk.vm.ci.hotspot.HotSpotCallingConventionType.NativeCall;
import static org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage.RegisterEffect.COMPUTES_REGISTERS_KILLED;
import static org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage.RegisterEffect.DESTROYS_ALL_CALLER_SAVE_REGISTERS;
import static org.graalvm.compiler.nodes.CallTargetNode.InvokeKind.Static;
import static org.graalvm.compiler.nodes.ConstantNode.forBoolean;
import org.graalvm.compiler.core.common.CompilationIdentifier;
import org.graalvm.compiler.core.common.LIRKind;
import org.graalvm.compiler.core.common.spi.ForeignCallDescriptor;
import org.graalvm.compiler.core.common.type.Stamp;
import org.graalvm.compiler.core.common.type.StampFactory;
import org.graalvm.compiler.core.common.type.StampPair;
import org.graalvm.compiler.debug.DebugContext;
import org.graalvm.compiler.debug.GraalError;
import org.graalvm.compiler.debug.JavaMethodContext;
import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage;
import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage.Reexecutability;
import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage.Transition;
import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkageImpl;
import org.graalvm.compiler.hotspot.meta.HotSpotLoweringProvider;
import org.graalvm.compiler.hotspot.meta.HotSpotProviders;
import org.graalvm.compiler.hotspot.nodes.StubForeignCallNode;
import org.graalvm.compiler.hotspot.stubs.ForeignCallSnippets.Templates;
import org.graalvm.compiler.nodes.InvokeNode;
import org.graalvm.compiler.nodes.ParameterNode;
import org.graalvm.compiler.nodes.ReturnNode;
import org.graalvm.compiler.nodes.StructuredGraph;
import org.graalvm.compiler.nodes.ValueNode;
import org.graalvm.compiler.options.OptionValues;
import org.graalvm.compiler.phases.common.RemoveValueProxyPhase;
import org.graalvm.compiler.replacements.GraphKit;
import org.graalvm.compiler.replacements.nodes.ReadRegisterNode;
import org.graalvm.compiler.word.Word;
import org.graalvm.compiler.word.WordTypes;
import jdk.internal.vm.compiler.word.LocationIdentity;
import jdk.vm.ci.hotspot.HotSpotJVMCIRuntime;
import jdk.vm.ci.hotspot.HotSpotSignature;
import jdk.vm.ci.meta.JavaKind;
import jdk.vm.ci.meta.JavaMethod;
import jdk.vm.ci.meta.JavaType;
import jdk.vm.ci.meta.MetaAccessProvider;
import jdk.vm.ci.meta.ResolvedJavaMethod;
import jdk.vm.ci.meta.ResolvedJavaType;
import jdk.vm.ci.meta.Signature;
/**
* A {@linkplain #getGraph generated} stub for a {@link Transition non-leaf} foreign call from
* compiled code. A stub is required for such calls as the caller may be scheduled for
* deoptimization while the call is in progress. And since these are foreign/runtime calls on slow
* paths, we don't want to force the register allocator to spill around the call. As such, this stub
* saves and restores all allocatable registers. It also
* {@linkplain ForeignCallSnippets#handlePendingException handles} any exceptions raised during the
* foreign call.
*/
public class ForeignCallStub extends Stub {
private final HotSpotJVMCIRuntime jvmciRuntime;
/**
* The target of the call.
*/
private final HotSpotForeignCallLinkage target;
/**
* Specifies if the JavaThread value for the current thread is to be prepended to the arguments
* for the call to {@link #target}.
*/
protected final boolean prependThread;
/**
* Creates a stub for a call to code at a given address.
*
* @param address the address of the code to call
* @param descriptor the signature of the call to this stub
* @param prependThread true if the JavaThread value for the current thread is to be prepended
* to the arguments for the call to {@code address}
* @param reexecutability specifies if the stub call can be re-executed without (meaningful)
* side effects. Deoptimization will not return to a point before a stub call that
* cannot be re-executed.
* @param killedLocations the memory locations killed by the stub call
*/
public ForeignCallStub(OptionValues options, HotSpotJVMCIRuntime runtime, HotSpotProviders providers, long address, ForeignCallDescriptor descriptor, boolean prependThread,
Transition transition, Reexecutability reexecutability, LocationIdentity... killedLocations) {
super(options, providers, HotSpotForeignCallLinkageImpl.create(providers.getMetaAccess(), providers.getCodeCache(), providers.getWordTypes(), providers.getForeignCalls(), descriptor, 0L,
COMPUTES_REGISTERS_KILLED, JavaCall, JavaCallee, transition, reexecutability, killedLocations));
this.jvmciRuntime = runtime;
this.prependThread = prependThread;
MetaAccessProvider metaAccess = providers.getMetaAccess();
Class<?>[] targetParameterTypes = createTargetParameters(descriptor);
ForeignCallDescriptor targetSig = new ForeignCallDescriptor(descriptor.getName() + ":C", descriptor.getResultType(), targetParameterTypes);
target = HotSpotForeignCallLinkageImpl.create(metaAccess, providers.getCodeCache(), providers.getWordTypes(), providers.getForeignCalls(), targetSig, address,
DESTROYS_ALL_CALLER_SAVE_REGISTERS, NativeCall, NativeCall, transition, reexecutability, killedLocations);
}
/**
* Gets the linkage information for the call from this stub.
*/
public HotSpotForeignCallLinkage getTargetLinkage() {
return target;
}
private Class<?>[] createTargetParameters(ForeignCallDescriptor descriptor) {
Class<?>[] parameters = descriptor.getArgumentTypes();
if (prependThread) {
Class<?>[] newParameters = new Class<?>[parameters.length + 1];
System.arraycopy(parameters, 0, newParameters, 1, parameters.length);
newParameters[0] = Word.class;
return newParameters;
}
return parameters;
}
@Override
protected ResolvedJavaMethod getInstalledCodeOwner() {
return null;
}
private class DebugScopeContext implements JavaMethod, JavaMethodContext {
@Override
public JavaMethod asJavaMethod() {
return this;
}
@Override
public Signature getSignature() {
ForeignCallDescriptor d = linkage.getDescriptor();
MetaAccessProvider metaAccess = providers.getMetaAccess();
Class<?>[] arguments = d.getArgumentTypes();
ResolvedJavaType[] parameters = new ResolvedJavaType[arguments.length];
for (int i = 0; i < arguments.length; i++) {
parameters[i] = metaAccess.lookupJavaType(arguments[i]);
}
return new HotSpotSignature(jvmciRuntime, metaAccess.lookupJavaType(d.getResultType()), parameters);
}
@Override
public String getName() {
return linkage.getDescriptor().getName();
}
@Override
public JavaType getDeclaringClass() {
return providers.getMetaAccess().lookupJavaType(ForeignCallStub.class);
}
@Override
public String toString() {
return format("ForeignCallStub<%n(%p)>");
}
}
@Override
protected Object debugScopeContext() {
return new DebugScopeContext() {
};
}
/**
* Creates a graph for this stub.
* <p>
* If the stub returns an object, the graph created corresponds to this pseudo code:
*
* <pre>
* Object foreignFunctionStub(args...) {
* foreignFunction(currentThread, args);
* if ((shouldClearException && clearPendingException(thread())) || (!shouldClearException && hasPendingException(thread)) {
* getAndClearObjectResult(thread());
* DeoptimizeCallerNode.deopt(None, RuntimeConstraint);
* }
* return verifyObject(getAndClearObjectResult(thread()));
* }
* </pre>
*
* If the stub returns a primitive or word, the graph created corresponds to this pseudo code
* (using {@code int} as the primitive return type):
*
* <pre>
* int foreignFunctionStub(args...) {
* int result = foreignFunction(currentThread, args);
* if ((shouldClearException && clearPendingException(thread())) || (!shouldClearException && hasPendingException(thread)) {
* DeoptimizeCallerNode.deopt(None, RuntimeConstraint);
* }
* return result;
* }
* </pre>
*
* If the stub is void, the graph created corresponds to this pseudo code:
*
* <pre>
* void foreignFunctionStub(args...) {
* foreignFunction(currentThread, args);
* if ((shouldClearException && clearPendingException(thread())) || (!shouldClearException && hasPendingException(thread)) {
* DeoptimizeCallerNode.deopt(None, RuntimeConstraint);
* }
* }
* </pre>
*
* In each example above, the {@code currentThread} argument is the C++ JavaThread value (i.e.,
* %r15 on AMD64) and is only prepended if {@link #prependThread} is true.
*/
@Override
@SuppressWarnings("try")
protected StructuredGraph getGraph(DebugContext debug, CompilationIdentifier compilationId) {
WordTypes wordTypes = providers.getWordTypes();
Class<?>[] args = linkage.getDescriptor().getArgumentTypes();
boolean isObjectResult = !LIRKind.isValue(linkage.getOutgoingCallingConvention().getReturn());
// Do we want to clear the pending exception?
boolean shouldClearException = linkage.isReexecutable();
try {
HotSpotLoweringProvider lowerer = (HotSpotLoweringProvider) providers.getLowerer();
Templates foreignCallSnippets = lowerer.getForeignCallSnippets();
ResolvedJavaMethod handlePendingException = foreignCallSnippets.handlePendingException.getMethod();
ResolvedJavaMethod getAndClearObjectResult = foreignCallSnippets.getAndClearObjectResult.getMethod();
ResolvedJavaMethod verifyObject = foreignCallSnippets.verifyObject.getMethod();
ResolvedJavaMethod thisMethod = getGraphMethod();
GraphKit kit = new GraphKit(debug, thisMethod, providers, wordTypes, providers.getGraphBuilderPlugins(), compilationId, toString());
StructuredGraph graph = kit.getGraph();
ParameterNode[] params = createParameters(kit, args);
ReadRegisterNode thread = kit.append(new ReadRegisterNode(providers.getRegisters().getThreadRegister(), wordTypes.getWordKind(), true, false));
ValueNode result = createTargetCall(kit, params, thread);
createStaticInvoke(kit, handlePendingException, thread, forBoolean(shouldClearException, graph), forBoolean(isObjectResult, graph));
if (isObjectResult) {
InvokeNode object = createStaticInvoke(kit, getAndClearObjectResult, thread);
result = createStaticInvoke(kit, verifyObject, object);
}
kit.append(new ReturnNode(linkage.getDescriptor().getResultType() == void.class ? null : result));
debug.dump(DebugContext.VERBOSE_LEVEL, graph, "Initial stub graph");
kit.inlineInvokes("Foreign call stub.", "Backend");
new RemoveValueProxyPhase().apply(graph);
debug.dump(DebugContext.VERBOSE_LEVEL, graph, "Stub graph before compilation");
return graph;
} catch (Exception e) {
throw GraalError.shouldNotReachHere(e);
}
}
private static InvokeNode createStaticInvoke(GraphKit kit, ResolvedJavaMethod method, ValueNode... args) {
return kit.createInvoke(method, Static, null, UNKNOWN_BCI, args);
}
private ResolvedJavaMethod getGraphMethod() {
ResolvedJavaMethod thisMethod = null;
for (ResolvedJavaMethod method : providers.getMetaAccess().lookupJavaType(ForeignCallStub.class).getDeclaredMethods()) {
if (method.getName().equals("getGraph")) {
if (thisMethod == null) {
thisMethod = method;
} else {
throw new InternalError("getGraph is ambiguous");
}
}
}
if (thisMethod == null) {
throw new InternalError("Can't find getGraph");
}
return thisMethod;
}
private ParameterNode[] createParameters(GraphKit kit, Class<?>[] args) {
ParameterNode[] params = new ParameterNode[args.length];
ResolvedJavaType accessingClass = providers.getMetaAccess().lookupJavaType(getClass());
for (int i = 0; i < args.length; i++) {
ResolvedJavaType type = providers.getMetaAccess().lookupJavaType(args[i]).resolve(accessingClass);
StampPair stamp = StampFactory.forDeclaredType(kit.getGraph().getAssumptions(), type, false);
ParameterNode param = kit.unique(new ParameterNode(i, stamp));
params[i] = param;
}
return params;
}
private StubForeignCallNode createTargetCall(GraphKit kit, ParameterNode[] params, ReadRegisterNode thread) {
Stamp stamp = StampFactory.forKind(JavaKind.fromJavaClass(target.getDescriptor().getResultType()));
if (prependThread) {
ValueNode[] targetArguments = new ValueNode[1 + params.length];
targetArguments[0] = thread;
System.arraycopy(params, 0, targetArguments, 1, params.length);
return kit.append(new StubForeignCallNode(providers.getForeignCalls(), stamp, target.getDescriptor(), targetArguments));
} else {
return kit.append(new StubForeignCallNode(providers.getForeignCalls(), stamp, target.getDescriptor(), params));
}
}
}