1 /*
2 * Copyright (c) 2012, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23 package org.graalvm.compiler.hotspot.stubs;
24
25 import static org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage.RegisterEffect.DESTROYS_REGISTERS;
26 import static org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage.RegisterEffect.PRESERVES_REGISTERS;
27 import static jdk.vm.ci.hotspot.HotSpotCallingConventionType.JavaCall;
28 import static jdk.vm.ci.hotspot.HotSpotCallingConventionType.JavaCallee;
29 import static jdk.vm.ci.hotspot.HotSpotCallingConventionType.NativeCall;
30
31 import org.graalvm.compiler.core.common.CompilationIdentifier;
32 import org.graalvm.compiler.core.common.LIRKind;
33 import org.graalvm.compiler.core.common.LocationIdentity;
34 import org.graalvm.compiler.core.common.spi.ForeignCallDescriptor;
35 import org.graalvm.compiler.core.common.type.StampFactory;
36 import org.graalvm.compiler.core.common.type.StampPair;
37 import org.graalvm.compiler.debug.Debug;
38 import org.graalvm.compiler.debug.JavaMethodContext;
39 import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage;
40 import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage.Transition;
41 import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkageImpl;
42 import org.graalvm.compiler.hotspot.meta.HotSpotProviders;
43 import org.graalvm.compiler.hotspot.nodes.StubForeignCallNode;
44 import org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil;
45 import org.graalvm.compiler.nodes.ConstantNode;
46 import org.graalvm.compiler.nodes.InvokeNode;
47 import org.graalvm.compiler.nodes.ParameterNode;
48 import org.graalvm.compiler.nodes.ReturnNode;
49 import org.graalvm.compiler.nodes.StructuredGraph;
50 import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;
51 import org.graalvm.compiler.nodes.ValueNode;
52 import org.graalvm.compiler.replacements.GraphKit;
53 import org.graalvm.compiler.replacements.nodes.ReadRegisterNode;
54 import org.graalvm.compiler.word.Word;
55 import org.graalvm.compiler.word.WordTypes;
56
57 import jdk.vm.ci.hotspot.HotSpotJVMCIRuntimeProvider;
58 import jdk.vm.ci.hotspot.HotSpotSignature;
59 import jdk.vm.ci.meta.JavaMethod;
60 import jdk.vm.ci.meta.JavaType;
61 import jdk.vm.ci.meta.MetaAccessProvider;
62 import jdk.vm.ci.meta.ResolvedJavaMethod;
63 import jdk.vm.ci.meta.ResolvedJavaType;
64 import jdk.vm.ci.meta.Signature;
65
66 /**
67 * A {@linkplain #getGraph generated} stub for a {@link Transition non-leaf} foreign call from
68 * compiled code. A stub is required for such calls as the caller may be scheduled for
69 * deoptimization while the call is in progress. And since these are foreign/runtime calls on slow
70 * paths, we don't want to force the register allocator to spill around the call. As such, this stub
71 * saves and restores all allocatable registers. It also
72 * {@linkplain StubUtil#handlePendingException(Word, boolean) handles} any exceptions raised during
73 * the foreign call.
74 */
75 public class ForeignCallStub extends Stub {
76
77 private final HotSpotJVMCIRuntimeProvider jvmciRuntime;
78
79 /**
80 * The target of the call.
81 */
82 private final HotSpotForeignCallLinkage target;
83
84 /**
85 * Specifies if the JavaThread value for the current thread is to be prepended to the arguments
86 * for the call to {@link #target}.
87 */
88 protected final boolean prependThread;
89
90 /**
91 * Creates a stub for a call to code at a given address.
92 *
93 * @param address the address of the code to call
94 * @param descriptor the signature of the call to this stub
95 * @param prependThread true if the JavaThread value for the current thread is to be prepended
96 * to the arguments for the call to {@code address}
97 * @param reexecutable specifies if the stub call can be re-executed without (meaningful) side
98 * effects. Deoptimization will not return to a point before a stub call that cannot
99 * be re-executed.
100 * @param killedLocations the memory locations killed by the stub call
101 */
102 public ForeignCallStub(HotSpotJVMCIRuntimeProvider runtime, HotSpotProviders providers, long address, ForeignCallDescriptor descriptor, boolean prependThread, Transition transition,
103 boolean reexecutable, LocationIdentity... killedLocations) {
104 super(providers, HotSpotForeignCallLinkageImpl.create(providers.getMetaAccess(), providers.getCodeCache(), providers.getWordTypes(), providers.getForeignCalls(), descriptor, 0L,
105 PRESERVES_REGISTERS, JavaCall, JavaCallee, transition, reexecutable, killedLocations));
106 this.jvmciRuntime = runtime;
107 this.prependThread = prependThread;
108 Class<?>[] targetParameterTypes = createTargetParameters(descriptor);
109 ForeignCallDescriptor targetSig = new ForeignCallDescriptor(descriptor.getName() + ":C", descriptor.getResultType(), targetParameterTypes);
110 target = HotSpotForeignCallLinkageImpl.create(providers.getMetaAccess(), providers.getCodeCache(), providers.getWordTypes(), providers.getForeignCalls(), targetSig, address,
111 DESTROYS_REGISTERS, NativeCall, NativeCall, transition, reexecutable, killedLocations);
112 }
113
114 /**
115 * Gets the linkage information for the call from this stub.
116 */
117 public HotSpotForeignCallLinkage getTargetLinkage() {
118 return target;
119 }
120
121 private Class<?>[] createTargetParameters(ForeignCallDescriptor descriptor) {
122 Class<?>[] parameters = descriptor.getArgumentTypes();
123 if (prependThread) {
124 Class<?>[] newParameters = new Class<?>[parameters.length + 1];
125 System.arraycopy(parameters, 0, newParameters, 1, parameters.length);
126 newParameters[0] = Word.class;
127 return newParameters;
128 }
129 return parameters;
130 }
131
132 @Override
133 protected ResolvedJavaMethod getInstalledCodeOwner() {
134 return null;
135 }
136
137 private class DebugScopeContext implements JavaMethod, JavaMethodContext {
138 @Override
139 public JavaMethod asJavaMethod() {
140 return this;
141 }
142
143 @Override
144 public Signature getSignature() {
145 ForeignCallDescriptor d = linkage.getDescriptor();
146 MetaAccessProvider metaAccess = providers.getMetaAccess();
147 Class<?>[] arguments = d.getArgumentTypes();
148 ResolvedJavaType[] parameters = new ResolvedJavaType[arguments.length];
149 for (int i = 0; i < arguments.length; i++) {
150 parameters[i] = metaAccess.lookupJavaType(arguments[i]);
151 }
152 return new HotSpotSignature(jvmciRuntime, metaAccess.lookupJavaType(d.getResultType()), parameters);
153 }
154
155 @Override
156 public String getName() {
157 return linkage.getDescriptor().getName();
158 }
159
160 @Override
161 public JavaType getDeclaringClass() {
162 return providers.getMetaAccess().lookupJavaType(ForeignCallStub.class);
163 }
164
165 @Override
166 public String toString() {
167 return format("ForeignCallStub<%n(%p)>");
168 }
169 }
170
171 @Override
172 protected Object debugScopeContext() {
173 return new DebugScopeContext() {
174
175 };
176 }
177
178 /**
179 * Creates a graph for this stub.
180 * <p>
181 * If the stub returns an object, the graph created corresponds to this pseudo code:
182 *
183 * <pre>
184 * Object foreignFunctionStub(args...) {
185 * foreignFunction(currentThread, args);
186 * if (clearPendingException(thread())) {
187 * getAndClearObjectResult(thread());
188 * DeoptimizeCallerNode.deopt(InvalidateReprofile, RuntimeConstraint);
189 * }
190 * return verifyObject(getAndClearObjectResult(thread()));
191 * }
192 * </pre>
193 *
194 * If the stub returns a primitive or word, the graph created corresponds to this pseudo code
195 * (using {@code int} as the primitive return type):
196 *
197 * <pre>
198 * int foreignFunctionStub(args...) {
199 * int result = foreignFunction(currentThread, args);
200 * if (clearPendingException(thread())) {
201 * DeoptimizeCallerNode.deopt(InvalidateReprofile, RuntimeConstraint);
202 * }
203 * return result;
204 * }
205 * </pre>
206 *
207 * If the stub is void, the graph created corresponds to this pseudo code:
208 *
209 * <pre>
210 * void foreignFunctionStub(args...) {
211 * foreignFunction(currentThread, args);
212 * if (clearPendingException(thread())) {
213 * DeoptimizeCallerNode.deopt(InvalidateReprofile, RuntimeConstraint);
214 * }
215 * }
216 * </pre>
217 *
218 * In each example above, the {@code currentThread} argument is the C++ JavaThread value (i.e.,
219 * %r15 on AMD64) and is only prepended if {@link #prependThread} is true.
220 */
221 @Override
222 protected StructuredGraph getGraph(CompilationIdentifier compilationId) {
223 WordTypes wordTypes = providers.getWordTypes();
224 Class<?>[] args = linkage.getDescriptor().getArgumentTypes();
225 boolean isObjectResult = !LIRKind.isValue(linkage.getOutgoingCallingConvention().getReturn());
226
227 StructuredGraph graph = new StructuredGraph(toString(), null, AllowAssumptions.NO, compilationId);
228 graph.disableUnsafeAccessTracking();
229
230 GraphKit kit = new GraphKit(graph, providers, wordTypes, providers.getGraphBuilderPlugins());
231 ParameterNode[] params = createParameters(kit, args);
232
233 ReadRegisterNode thread = kit.append(new ReadRegisterNode(providers.getRegisters().getThreadRegister(), wordTypes.getWordKind(), true, false));
234 ValueNode result = createTargetCall(kit, params, thread);
235 kit.createInvoke(StubUtil.class, "handlePendingException", thread, ConstantNode.forBoolean(isObjectResult, graph));
236 if (isObjectResult) {
237 InvokeNode object = kit.createInvoke(HotSpotReplacementsUtil.class, "getAndClearObjectResult", thread);
238 result = kit.createInvoke(StubUtil.class, "verifyObject", object);
239 }
240 kit.append(new ReturnNode(linkage.getDescriptor().getResultType() == void.class ? null : result));
241
242 if (Debug.isDumpEnabled(Debug.INFO_LOG_LEVEL)) {
243 Debug.dump(Debug.INFO_LOG_LEVEL, graph, "Initial stub graph");
244 }
245
246 kit.inlineInvokes();
247
248 if (Debug.isDumpEnabled(Debug.INFO_LOG_LEVEL)) {
249 Debug.dump(Debug.INFO_LOG_LEVEL, graph, "Stub graph before compilation");
250 }
251
252 return graph;
253 }
254
255 private ParameterNode[] createParameters(GraphKit kit, Class<?>[] args) {
256 ParameterNode[] params = new ParameterNode[args.length];
257 ResolvedJavaType accessingClass = providers.getMetaAccess().lookupJavaType(getClass());
258 for (int i = 0; i < args.length; i++) {
259 ResolvedJavaType type = providers.getMetaAccess().lookupJavaType(args[i]).resolve(accessingClass);
260 StampPair stamp = StampFactory.forDeclaredType(kit.getGraph().getAssumptions(), type, false);
261 ParameterNode param = kit.unique(new ParameterNode(i, stamp));
262 params[i] = param;
263 }
264 return params;
265 }
266
267 private StubForeignCallNode createTargetCall(GraphKit kit, ParameterNode[] params, ReadRegisterNode thread) {
268 if (prependThread) {
269 ValueNode[] targetArguments = new ValueNode[1 + params.length];
270 targetArguments[0] = thread;
271 System.arraycopy(params, 0, targetArguments, 1, params.length);
272 return kit.append(new StubForeignCallNode(providers.getForeignCalls(), target.getDescriptor(), targetArguments));
273 } else {
274 return kit.append(new StubForeignCallNode(providers.getForeignCalls(), target.getDescriptor(), params));
275 }
276 }
277 }