/**
* 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 (clearPendingException(thread())) {
* getAndClearObjectResult(thread());
* DeoptimizeCallerNode.deopt(InvalidateReprofile, 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 (clearPendingException(thread())) {
* DeoptimizeCallerNode.deopt(InvalidateReprofile, 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 (clearPendingException(thread())) {
* DeoptimizeCallerNode.deopt(InvalidateReprofile, 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
protected StructuredGraph getGraph() {
WordTypes wordTypes = providers.getWordTypes();
Class<?>[] args = linkage.getDescriptor().getArgumentTypes();
boolean isObjectResult =
!linkage.getOutgoingCallingConvention().getReturn().getLIRKind().isValue();
StructuredGraph graph = new StructuredGraph(toString(), null, AllowAssumptions.NO);
graph.disableUnsafeAccessTracking();
GraphKit kit = new GraphKit(graph, providers, wordTypes, providers.getGraphBuilderPlugins());
ParameterNode[] params = createParameters(kit, args);
ReadRegisterNode thread =
kit.append(
new ReadRegisterNode(
providers.getRegisters().getThreadRegister(),
wordTypes.getWordKind(),
true,
false));
ValueNode result = createTargetCall(kit, params, thread);
kit.createInvoke(
StubUtil.class,
"handlePendingException",
thread,
ConstantNode.forBoolean(isObjectResult, graph));
if (isObjectResult) {
InvokeNode object =
kit.createInvoke(HotSpotReplacementsUtil.class, "getAndClearObjectResult", thread);
result = kit.createInvoke(StubUtil.class, "verifyObject", object);
}
kit.append(
new ReturnNode(linkage.getDescriptor().getResultType() == void.class ? null : result));
if (Debug.isDumpEnabled()) {
Debug.dump(graph, "Initial stub graph");
}
kit.inlineInvokes();
if (Debug.isDumpEnabled()) {
Debug.dump(graph, "Stub graph before compilation");
}
return graph;
}
