1 /*
2 * Copyright (c) 2011, 2018, 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
24
25 package org.graalvm.compiler.replacements.arraycopy;
26
27 import static org.graalvm.compiler.nodes.extended.BranchProbabilityNode.FREQUENT_PROBABILITY;
28 import static org.graalvm.compiler.nodes.extended.BranchProbabilityNode.LIKELY_PROBABILITY;
29 import static org.graalvm.compiler.nodes.extended.BranchProbabilityNode.NOT_FREQUENT_PROBABILITY;
30 import static org.graalvm.compiler.nodes.extended.BranchProbabilityNode.SLOW_PATH_PROBABILITY;
31 import static org.graalvm.compiler.nodes.extended.BranchProbabilityNode.probability;
32
33 import java.lang.reflect.Method;
34 import java.util.EnumMap;
35
36 import jdk.internal.vm.compiler.collections.UnmodifiableEconomicMap;
37 import org.graalvm.compiler.api.directives.GraalDirectives;
38 import org.graalvm.compiler.api.replacements.Fold;
39 import org.graalvm.compiler.api.replacements.Fold.InjectedParameter;
40 import org.graalvm.compiler.api.replacements.Snippet;
41 import org.graalvm.compiler.api.replacements.Snippet.ConstantParameter;
42 import org.graalvm.compiler.api.replacements.SnippetReflectionProvider;
43 import org.graalvm.compiler.debug.DebugHandlersFactory;
44 import org.graalvm.compiler.debug.GraalError;
45 import org.graalvm.compiler.graph.Node;
46 import org.graalvm.compiler.nodes.CallTargetNode;
47 import org.graalvm.compiler.nodes.DeoptimizeNode;
48 import org.graalvm.compiler.nodes.InvokeNode;
49 import org.graalvm.compiler.nodes.InvokeWithExceptionNode;
50 import org.graalvm.compiler.nodes.NamedLocationIdentity;
51 import org.graalvm.compiler.nodes.NodeView;
52 import org.graalvm.compiler.nodes.PiNode;
53 import org.graalvm.compiler.nodes.StructuredGraph;
54 import org.graalvm.compiler.nodes.ValueNode;
55 import org.graalvm.compiler.nodes.extended.RawLoadNode;
56 import org.graalvm.compiler.nodes.extended.RawStoreNode;
57 import org.graalvm.compiler.nodes.java.ArrayLengthNode;
58 import org.graalvm.compiler.nodes.spi.LoweringTool;
59 import org.graalvm.compiler.nodes.type.StampTool;
60 import org.graalvm.compiler.nodes.util.GraphUtil;
61 import org.graalvm.compiler.options.OptionValues;
62 import org.graalvm.compiler.phases.util.Providers;
63 import org.graalvm.compiler.replacements.ReplacementsUtil;
64 import org.graalvm.compiler.replacements.SnippetCounter;
65 import org.graalvm.compiler.replacements.SnippetCounter.Group;
66 import org.graalvm.compiler.replacements.SnippetCounter.Group.Factory;
67 import org.graalvm.compiler.replacements.SnippetIntegerHistogram;
68 import org.graalvm.compiler.replacements.SnippetTemplate;
69 import org.graalvm.compiler.replacements.SnippetTemplate.Arguments;
70 import org.graalvm.compiler.replacements.SnippetTemplate.SnippetInfo;
71 import org.graalvm.compiler.replacements.Snippets;
72 import org.graalvm.compiler.replacements.nodes.BasicArrayCopyNode;
73 import org.graalvm.compiler.replacements.nodes.ExplodeLoopNode;
74 import org.graalvm.compiler.word.Word;
75 import jdk.internal.vm.compiler.word.LocationIdentity;
76 import jdk.internal.vm.compiler.word.Pointer;
77
78 import jdk.vm.ci.code.TargetDescription;
79 import jdk.vm.ci.meta.DeoptimizationAction;
80 import jdk.vm.ci.meta.DeoptimizationReason;
81 import jdk.vm.ci.meta.JavaKind;
82 import jdk.vm.ci.meta.MetaAccessProvider;
83 import jdk.vm.ci.meta.ResolvedJavaMethod;
84 import jdk.vm.ci.meta.ResolvedJavaType;
85
86 public abstract class ArrayCopySnippets implements Snippets {
87
88 private enum ArrayCopyTypeCheck {
89 UNDEFINED_ARRAY_TYPE_CHECK,
90 // either we know that both objects are arrays and have the same type,
91 // or we apply generic array copy snippet, which enforces type check
92 NO_ARRAY_TYPE_CHECK,
93 // can be used when we know that one of the objects is a primitive array
94 HUB_BASED_ARRAY_TYPE_CHECK,
95 // can be used when we know that one of the objects is an object array
96 LAYOUT_HELPER_BASED_ARRAY_TYPE_CHECK
97 }
98
99 /** Marker value for the {@link InjectedParameter} injected parameter. */
100 static final MetaAccessProvider INJECTED_META_ACCESS = null;
101
102 public abstract Pointer loadHub(Object nonNullSrc);
103
104 public abstract Pointer getDestElemClass(Pointer destKlass);
105
106 public abstract Word getSuperCheckOffset(Pointer destElemKlass);
107
108 public abstract int getReadLayoutHelper(Pointer srcHub);
109
110 protected abstract int heapWordSize();
111
112 @Snippet
113 public void arraycopyZeroLengthSnippet(Object src, int srcPos, Object dest, int destPos, int length, @ConstantParameter ArrayCopyTypeCheck arrayTypeCheck,
114 @ConstantParameter Counters counters) {
115 Object nonNullSrc = GraalDirectives.guardingNonNull(src);
116 Object nonNullDest = GraalDirectives.guardingNonNull(dest);
117 this.checkArrayTypes(nonNullSrc, nonNullDest, arrayTypeCheck);
118 checkLimits(nonNullSrc, srcPos, nonNullDest, destPos, length, counters);
119 counters.zeroLengthStaticCounter.inc();
120 }
121
122 @Snippet
123 public void arraycopyExactSnippet(Object src, int srcPos, Object dest, int destPos, int length, @ConstantParameter ArrayCopyTypeCheck arrayTypeCheck,
124 @ConstantParameter JavaKind elementKind, @ConstantParameter SnippetCounter elementKindCounter, @ConstantParameter SnippetCounter elementKindCopiedCounter,
125 @ConstantParameter Counters counters) {
126 Object nonNullSrc = GraalDirectives.guardingNonNull(src);
127 Object nonNullDest = GraalDirectives.guardingNonNull(dest);
128 checkArrayTypes(nonNullSrc, nonNullDest, arrayTypeCheck);
129 checkLimits(nonNullSrc, srcPos, nonNullDest, destPos, length, counters);
130 incrementLengthCounter(length, counters);
131
132 elementKindCounter.inc();
133 elementKindCopiedCounter.add(length);
134 ArrayCopyCallNode.arraycopy(nonNullSrc, srcPos, nonNullDest, destPos, length, elementKind, heapWordSize());
135 }
136
137 @Snippet
138 public void arraycopyUnrolledSnippet(Object src, int srcPos, Object dest, int destPos, int length, @ConstantParameter ArrayCopyTypeCheck arrayTypeCheck,
139 @ConstantParameter JavaKind elementKind, @ConstantParameter int unrolledLength, @ConstantParameter Counters counters) {
140 Object nonNullSrc = GraalDirectives.guardingNonNull(src);
141 Object nonNullDest = GraalDirectives.guardingNonNull(dest);
142 checkArrayTypes(nonNullSrc, nonNullDest, arrayTypeCheck);
143 checkLimits(nonNullSrc, srcPos, nonNullDest, destPos, length, counters);
144 incrementLengthCounter(length, counters);
145
146 unrolledArraycopyWork(nonNullSrc, srcPos, nonNullDest, destPos, unrolledLength, elementKind);
147 }
148
149 @Snippet
150 public void arraycopyCheckcastSnippet(Object src, int srcPos, Object dest, int destPos, int length, @ConstantParameter ArrayCopyTypeCheck arrayTypeCheck,
151 @ConstantParameter Counters counters, @ConstantParameter SnippetInfo workSnippet, @ConstantParameter JavaKind elementKind) {
152 Object nonNullSrc = GraalDirectives.guardingNonNull(src);
153 Object nonNullDest = GraalDirectives.guardingNonNull(dest);
154 checkArrayTypes(nonNullSrc, nonNullDest, arrayTypeCheck);
155 checkLimits(nonNullSrc, srcPos, nonNullDest, destPos, length, counters);
156 incrementLengthCounter(length, counters);
157
158 ArrayCopyWithSlowPathNode.arraycopy(nonNullSrc, srcPos, nonNullDest, destPos, length, workSnippet, elementKind);
159 }
160
161 @Snippet
162 public void arraycopyGenericSnippet(Object src, int srcPos, Object dest, int destPos, int length, @ConstantParameter ArrayCopyTypeCheck arrayTypeCheck, @ConstantParameter Counters counters,
163 @ConstantParameter SnippetInfo workSnippet, @ConstantParameter JavaKind elementKind) {
164 Object nonNullSrc = GraalDirectives.guardingNonNull(src);
165 Object nonNullDest = GraalDirectives.guardingNonNull(dest);
166 checkArrayTypes(nonNullSrc, nonNullDest, arrayTypeCheck);
167 checkLimits(nonNullSrc, srcPos, nonNullDest, destPos, length, counters);
168 incrementLengthCounter(length, counters);
169
170 ArrayCopyWithSlowPathNode.arraycopy(nonNullSrc, srcPos, nonNullDest, destPos, length, workSnippet, elementKind);
171 }
172
173 @Snippet
174 public static void arraycopyNativeSnippet(Object src, int srcPos, Object dest, int destPos, int length, @ConstantParameter Counters counters) {
175 // all checks are done in the native method, so no need to emit additional checks here
176 incrementLengthCounter(length, counters);
177 counters.systemArraycopyCounter.inc();
178 counters.systemArraycopyCopiedCounter.add(length);
179
180 System.arraycopy(src, srcPos, dest, destPos, length);
181 }
182
183 @Fold
184 static LocationIdentity getArrayLocation(JavaKind kind) {
185 return NamedLocationIdentity.getArrayLocation(kind);
186 }
187
188 private static void unrolledArraycopyWork(Object nonNullSrc, int srcPos, Object nonNullDest, int destPos, int length, JavaKind elementKind) {
189 int scale = ReplacementsUtil.arrayIndexScale(INJECTED_META_ACCESS, elementKind);
190 int arrayBaseOffset = ReplacementsUtil.getArrayBaseOffset(INJECTED_META_ACCESS, elementKind);
191 LocationIdentity arrayLocation = getArrayLocation(elementKind);
192
193 long sourceOffset = arrayBaseOffset + (long) srcPos * scale;
194 long destOffset = arrayBaseOffset + (long) destPos * scale;
195 long position = 0;
196 long delta = scale;
197 if (probability(NOT_FREQUENT_PROBABILITY, nonNullSrc == nonNullDest && srcPos < destPos)) {
198 // bad aliased case so we need to copy the array from back to front
199 position = (long) (length - 1) * scale;
200 delta = -delta;
201 }
202
203 // the length was already checked before - we can emit unconditional instructions
204 ExplodeLoopNode.explodeLoop();
205 for (int iteration = 0; iteration < length; iteration++) {
206 Object value = RawLoadNode.load(nonNullSrc, sourceOffset + position, elementKind, arrayLocation);
207 RawStoreNode.storeObject(nonNullDest, destOffset + position, value, elementKind, arrayLocation, false);
208 position += delta;
209 }
210 }
211
212 @Snippet(allowPartialIntrinsicArgumentMismatch = true)
213 public void checkcastArraycopyWithSlowPathWork(Object src, int srcPos, Object dest, int destPos, int length, @ConstantParameter Counters counters) {
214 if (probability(FREQUENT_PROBABILITY, length > 0)) {
215 Object nonNullSrc = PiNode.asNonNullObject(src);
216 Object nonNullDest = PiNode.asNonNullObject(dest);
217 Pointer srcKlass = loadHub(nonNullSrc);
218 Pointer destKlass = loadHub(nonNullDest);
219 if (probability(LIKELY_PROBABILITY, srcKlass == destKlass)) {
220 // no storecheck required.
221 counters.objectCheckcastSameTypeCounter.inc();
222 counters.objectCheckcastSameTypeCopiedCounter.add(length);
223 ArrayCopyCallNode.arraycopyObjectKillsAny(nonNullSrc, srcPos, nonNullDest, destPos, length, heapWordSize());
224 } else {
225 Pointer destElemKlass = getDestElemClass(destKlass);
226 Word superCheckOffset = getSuperCheckOffset(destElemKlass);
227
228 counters.objectCheckcastDifferentTypeCounter.inc();
229 counters.objectCheckcastDifferentTypeCopiedCounter.add(length);
230
231 int copiedElements = CheckcastArrayCopyCallNode.checkcastArraycopy(nonNullSrc, srcPos, nonNullDest, destPos, length, superCheckOffset, destElemKlass, false);
232 if (probability(SLOW_PATH_PROBABILITY, copiedElements != 0)) {
233 /*
234 * the stub doesn't throw the ArrayStoreException, but returns the number of
235 * copied elements (xor'd with -1).
236 */
237 copiedElements ^= -1;
238 System.arraycopy(nonNullSrc, srcPos + copiedElements, nonNullDest, destPos + copiedElements, length - copiedElements);
239 }
240 }
241 }
242 }
243
244 @Snippet(allowPartialIntrinsicArgumentMismatch = true)
245 public void genericArraycopyWithSlowPathWork(Object src, int srcPos, Object dest, int destPos, int length, @ConstantParameter Counters counters) {
246 // The length > 0 check should not be placed here because generic array copy stub should
247 // enforce type check. This is fine performance-wise because this snippet is rarely used.
248 counters.genericArraycopyDifferentTypeCounter.inc();
249 counters.genericArraycopyDifferentTypeCopiedCounter.add(length);
250 int copiedElements = GenericArrayCopyCallNode.genericArraycopy(src, srcPos, dest, destPos, length);
251 if (probability(SLOW_PATH_PROBABILITY, copiedElements != 0)) {
252 /*
253 * the stub doesn't throw the ArrayStoreException, but returns the number of copied
254 * elements (xor'd with -1).
255 */
256 copiedElements ^= -1;
257 System.arraycopy(src, srcPos + copiedElements, dest, destPos + copiedElements, length - copiedElements);
258 }
259 }
260
261 private static void incrementLengthCounter(int length, Counters counters) {
262 counters.lengthHistogram.inc(length);
263 }
264
265 private static void checkLimits(Object src, int srcPos, Object dest, int destPos, int length, Counters counters) {
266 if (probability(SLOW_PATH_PROBABILITY, srcPos < 0) ||
267 probability(SLOW_PATH_PROBABILITY, destPos < 0) ||
268 probability(SLOW_PATH_PROBABILITY, length < 0) ||
269 probability(SLOW_PATH_PROBABILITY, srcPos > ArrayLengthNode.arrayLength(src) - length) ||
270 probability(SLOW_PATH_PROBABILITY, destPos > ArrayLengthNode.arrayLength(dest) - length)) {
271 counters.checkAIOOBECounter.inc();
272 DeoptimizeNode.deopt(DeoptimizationAction.None, DeoptimizationReason.RuntimeConstraint);
273 }
274 counters.checkSuccessCounter.inc();
275 }
276
277 private void checkArrayTypes(Object nonNullSrc, Object nonNullDest, ArrayCopyTypeCheck arrayTypeCheck) {
278 if (arrayTypeCheck == ArrayCopyTypeCheck.NO_ARRAY_TYPE_CHECK) {
279 // nothing to do
280 } else if (arrayTypeCheck == ArrayCopyTypeCheck.HUB_BASED_ARRAY_TYPE_CHECK) {
281 Pointer srcHub = loadHub(nonNullSrc);
282 Pointer destHub = loadHub(nonNullDest);
283 if (probability(SLOW_PATH_PROBABILITY, srcHub != destHub)) {
284 DeoptimizeNode.deopt(DeoptimizationAction.None, DeoptimizationReason.RuntimeConstraint);
285 }
286 } else if (arrayTypeCheck == ArrayCopyTypeCheck.LAYOUT_HELPER_BASED_ARRAY_TYPE_CHECK) {
287 Pointer srcHub = loadHub(nonNullSrc);
288 Pointer destHub = loadHub(nonNullDest);
289 if (probability(SLOW_PATH_PROBABILITY, getReadLayoutHelper(srcHub) != getReadLayoutHelper(destHub))) {
290 DeoptimizeNode.deopt(DeoptimizationAction.None, DeoptimizationReason.RuntimeConstraint);
291 }
292 } else {
293 ReplacementsUtil.staticAssert(false, "unknown array type check");
294 }
295 }
296
297 static class Counters {
298 final SnippetCounter checkSuccessCounter;
299 final SnippetCounter checkAIOOBECounter;
300
301 final SnippetCounter zeroLengthStaticCounter;
302 final SnippetIntegerHistogram lengthHistogram;
303
304 final SnippetCounter systemArraycopyCounter;
305 final SnippetCounter systemArraycopyCopiedCounter;
306
307 final SnippetCounter genericArraycopyDifferentTypeCopiedCounter;
308 final SnippetCounter genericArraycopyDifferentTypeCounter;
309
310 final SnippetCounter objectCheckcastSameTypeCopiedCounter;
311 final SnippetCounter objectCheckcastSameTypeCounter;
312 final SnippetCounter objectCheckcastDifferentTypeCopiedCounter;
313 final SnippetCounter objectCheckcastDifferentTypeCounter;
314
315 final EnumMap<JavaKind, SnippetCounter> arraycopyCallCounters = new EnumMap<>(JavaKind.class);
316 final EnumMap<JavaKind, SnippetCounter> arraycopyCallCopiedCounters = new EnumMap<>(JavaKind.class);
317
318 Counters(SnippetCounter.Group.Factory factory) {
319 final Group checkCounters = factory.createSnippetCounterGroup("System.arraycopy checkInputs");
320 final Group callCounters = factory.createSnippetCounterGroup("System.arraycopy calls");
321 final Group copiedElementsCounters = factory.createSnippetCounterGroup("System.arraycopy copied elements");
322 final Group lengthCounters = factory.createSnippetCounterGroup("System.arraycopy with 0-length");
323
324 checkSuccessCounter = new SnippetCounter(checkCounters, "checkSuccess", "checkSuccess");
325 checkAIOOBECounter = new SnippetCounter(checkCounters, "checkAIOOBE", "checkAIOOBE");
326
327 zeroLengthStaticCounter = new SnippetCounter(lengthCounters, "0-length copy static", "calls where the length is statically 0");
328 lengthHistogram = new SnippetIntegerHistogram(lengthCounters, 2, "length", "length");
329
330 systemArraycopyCounter = new SnippetCounter(callCounters, "native System.arraycopy", "JNI-based System.arraycopy call");
331 systemArraycopyCopiedCounter = new SnippetCounter(copiedElementsCounters, "native System.arraycopy", "JNI-based System.arraycopy call");
332
333 genericArraycopyDifferentTypeCounter = new SnippetCounter(callCounters, "generic[] stub", "generic arraycopy stub");
334 genericArraycopyDifferentTypeCopiedCounter = new SnippetCounter(copiedElementsCounters, "generic[] stub", "generic arraycopy stub");
335
336 objectCheckcastSameTypeCounter = new SnippetCounter(callCounters, "checkcast object[] (same-type)", "checkcast object[] stub but src.klass == dest.klass Object[] arrays");
337 objectCheckcastSameTypeCopiedCounter = new SnippetCounter(copiedElementsCounters, "checkcast object[] (same-type)", "checkcast object[] stub but src.klass == dest.klass Object[] arrays");
338 objectCheckcastDifferentTypeCounter = new SnippetCounter(callCounters, "checkcast object[] (store-check)", "checkcast object[] stub with store check");
339 objectCheckcastDifferentTypeCopiedCounter = new SnippetCounter(copiedElementsCounters, "checkcast object[] (store-check)", "checkcast object[] stub with store check");
340
341 createArraycopyCounter(JavaKind.Byte, callCounters, copiedElementsCounters);
342 createArraycopyCounter(JavaKind.Boolean, callCounters, copiedElementsCounters);
343 createArraycopyCounter(JavaKind.Char, callCounters, copiedElementsCounters);
344 createArraycopyCounter(JavaKind.Short, callCounters, copiedElementsCounters);
345 createArraycopyCounter(JavaKind.Int, callCounters, copiedElementsCounters);
346 createArraycopyCounter(JavaKind.Long, callCounters, copiedElementsCounters);
347 createArraycopyCounter(JavaKind.Float, callCounters, copiedElementsCounters);
348 createArraycopyCounter(JavaKind.Double, callCounters, copiedElementsCounters);
349 createArraycopyCounter(JavaKind.Object, callCounters, copiedElementsCounters);
350 }
351
352 void createArraycopyCounter(JavaKind kind, Group counters, Group copiedCounters) {
353 arraycopyCallCounters.put(kind, new SnippetCounter(counters, kind + "[] stub", "arraycopy call for " + kind + "[] arrays"));
354 arraycopyCallCopiedCounters.put(kind, new SnippetCounter(copiedCounters, kind + "[] stub", "arraycopy call for " + kind + "[] arrays"));
355 }
356 }
357
358 public static class Templates extends SnippetTemplate.AbstractTemplates {
359 private final SnippetInfo arraycopyGenericSnippet;
360 private final SnippetInfo arraycopyUnrolledSnippet;
361 private final SnippetInfo arraycopyExactSnippet;
362 private final SnippetInfo arraycopyZeroLengthSnippet;
363 private final SnippetInfo arraycopyCheckcastSnippet;
364 private final SnippetInfo arraycopyNativeSnippet;
365 private final SnippetInfo checkcastArraycopyWithSlowPathWork;
366 private final SnippetInfo genericArraycopyWithSlowPathWork;
367
368 private ResolvedJavaMethod originalArraycopy;
369 private final Counters counters;
370
371 public Templates(ArrayCopySnippets receiver, OptionValues options, Iterable<DebugHandlersFactory> factories, Factory factory, Providers providers,
372 SnippetReflectionProvider snippetReflection, TargetDescription target) {
373 super(options, factories, providers, snippetReflection, target);
374 this.counters = new Counters(factory);
375
376 arraycopyGenericSnippet = snippet(receiver, "arraycopyGenericSnippet");
377 arraycopyUnrolledSnippet = snippet(receiver, "arraycopyUnrolledSnippet");
378 arraycopyExactSnippet = snippet(receiver, "arraycopyExactSnippet");
379 arraycopyZeroLengthSnippet = snippet(receiver, "arraycopyZeroLengthSnippet");
380 arraycopyCheckcastSnippet = snippet(receiver, "arraycopyCheckcastSnippet");
381 arraycopyNativeSnippet = snippet(null, "arraycopyNativeSnippet");
382 checkcastArraycopyWithSlowPathWork = snippet(receiver, "checkcastArraycopyWithSlowPathWork");
383 genericArraycopyWithSlowPathWork = snippet(receiver, "genericArraycopyWithSlowPathWork");
384 }
385
386 protected SnippetInfo snippet(ArrayCopySnippets receiver, String methodName) {
387 SnippetInfo info = snippet(ArrayCopySnippets.class, methodName, receiver, LocationIdentity.any());
388 info.setOriginalMethod(originalArraycopy());
389 return info;
390 }
391
392 public void lower(ArrayCopyNode arraycopy, LoweringTool tool) {
393 JavaKind elementKind = selectComponentKind(arraycopy);
394 SnippetInfo snippetInfo;
395 ArrayCopyTypeCheck arrayTypeCheck;
396
397 ResolvedJavaType srcType = StampTool.typeOrNull(arraycopy.getSource().stamp(NodeView.DEFAULT));
398 ResolvedJavaType destType = StampTool.typeOrNull(arraycopy.getDestination().stamp(NodeView.DEFAULT));
399 if (!canBeArray(srcType) || !canBeArray(destType)) {
400 // at least one of the objects is definitely not an array - use the native call
401 // right away as the copying will fail anyways
402 snippetInfo = arraycopyNativeSnippet;
403 arrayTypeCheck = ArrayCopyTypeCheck.UNDEFINED_ARRAY_TYPE_CHECK;
404 } else {
405 ResolvedJavaType srcComponentType = srcType == null ? null : srcType.getComponentType();
406 ResolvedJavaType destComponentType = destType == null ? null : destType.getComponentType();
407
408 if (arraycopy.isExact()) {
409 // there is a sufficient type match - we don't need any additional type checks
410 snippetInfo = arraycopyExactSnippet;
411 arrayTypeCheck = ArrayCopyTypeCheck.NO_ARRAY_TYPE_CHECK;
412 } else if (srcComponentType == null && destComponentType == null) {
413 // we don't know anything about the types - use the generic copying
414 snippetInfo = arraycopyGenericSnippet;
415 // no need for additional type check to avoid duplicated work
416 arrayTypeCheck = ArrayCopyTypeCheck.NO_ARRAY_TYPE_CHECK;
417 } else if (srcComponentType != null && destComponentType != null) {
418 if (!srcComponentType.isPrimitive() && !destComponentType.isPrimitive()) {
419 // it depends on the array content if the copy succeeds - we need
420 // a type check for every store
421 snippetInfo = arraycopyCheckcastSnippet;
422 arrayTypeCheck = ArrayCopyTypeCheck.NO_ARRAY_TYPE_CHECK;
423 } else {
424 // one object is an object array, the other one is a primitive array.
425 // this copy will always fail - use the native call right away
426 assert !srcComponentType.equals(destComponentType) : "must be handled by arraycopy.isExact()";
427 snippetInfo = arraycopyNativeSnippet;
428 arrayTypeCheck = ArrayCopyTypeCheck.UNDEFINED_ARRAY_TYPE_CHECK;
429 }
430 } else {
431 ResolvedJavaType nonNullComponentType = srcComponentType != null ? srcComponentType : destComponentType;
432 if (nonNullComponentType.isPrimitive()) {
433 // one involved object is a primitive array - it is sufficient to directly
434 // compare the hub.
435 snippetInfo = arraycopyExactSnippet;
436 arrayTypeCheck = ArrayCopyTypeCheck.HUB_BASED_ARRAY_TYPE_CHECK;
437 elementKind = nonNullComponentType.getJavaKind();
438 } else {
439 // one involved object is an object array - the other array's element type
440 // may be primitive or object, hence we compare the layout helper.
441 snippetInfo = arraycopyCheckcastSnippet;
442 arrayTypeCheck = ArrayCopyTypeCheck.LAYOUT_HELPER_BASED_ARRAY_TYPE_CHECK;
443 }
444 }
445 }
446
447 // a few special cases that are easier to handle when all other variables already have a
448 // value
449 if (snippetInfo != arraycopyNativeSnippet && snippetInfo != arraycopyGenericSnippet && arraycopy.getLength().isConstant() && arraycopy.getLength().asJavaConstant().asLong() == 0) {
450 // Copying 0 element between object arrays with conflicting types will not throw an
451 // exception - once we pass the preliminary element type checks that we are not
452 // mixing arrays of different basic types, ArrayStoreException is only thrown when
453 // an *astore would have thrown it. Therefore, copying null between object arrays
454 // with conflicting types will also succeed (we do not optimize for such case here).
455 snippetInfo = arraycopyZeroLengthSnippet;
456 } else if (snippetInfo == arraycopyExactSnippet && shouldUnroll(arraycopy.getLength())) {
457 snippetInfo = arraycopyUnrolledSnippet;
458 }
459
460 // create the snippet
461 Arguments args = new Arguments(snippetInfo, arraycopy.graph().getGuardsStage(), tool.getLoweringStage());
462 args.add("src", arraycopy.getSource());
463 args.add("srcPos", arraycopy.getSourcePosition());
464 args.add("dest", arraycopy.getDestination());
465 args.add("destPos", arraycopy.getDestinationPosition());
466 args.add("length", arraycopy.getLength());
467 if (snippetInfo != arraycopyNativeSnippet) {
468 assert arrayTypeCheck != ArrayCopyTypeCheck.UNDEFINED_ARRAY_TYPE_CHECK;
469 args.addConst("arrayTypeCheck", arrayTypeCheck);
470 }
471 if (snippetInfo == arraycopyUnrolledSnippet) {
472 args.addConst("elementKind", elementKind != null ? elementKind : JavaKind.Illegal);
473 args.addConst("unrolledLength", arraycopy.getLength().asJavaConstant().asInt());
474 }
475 if (snippetInfo == arraycopyExactSnippet) {
476 assert elementKind != null;
477 args.addConst("elementKind", elementKind);
478 args.addConst("elementKindCounter", counters.arraycopyCallCounters.get(elementKind));
479 args.addConst("elementKindCopiedCounter", counters.arraycopyCallCopiedCounters.get(elementKind));
480 }
481 args.addConst("counters", counters);
482 if (snippetInfo == arraycopyCheckcastSnippet) {
483 args.addConst("workSnippet", checkcastArraycopyWithSlowPathWork);
484 args.addConst("elementKind", JavaKind.Illegal);
485 }
486 if (snippetInfo == arraycopyGenericSnippet) {
487 args.addConst("workSnippet", genericArraycopyWithSlowPathWork);
488 args.addConst("elementKind", JavaKind.Illegal);
489 }
490
491 instantiate(args, arraycopy);
492 }
493
494 public void lower(ArrayCopyWithSlowPathNode arraycopy, LoweringTool tool) {
495 StructuredGraph graph = arraycopy.graph();
496 if (!graph.getGuardsStage().areFrameStatesAtDeopts()) {
497 // if an arraycopy contains a slow path, we can't lower it right away
498 return;
499 }
500
501 SnippetInfo snippetInfo = arraycopy.getSnippet();
502 Arguments args = new Arguments(snippetInfo, graph.getGuardsStage(), tool.getLoweringStage());
503 args.add("src", arraycopy.getSource());
504 args.add("srcPos", arraycopy.getSourcePosition());
505 args.add("dest", arraycopy.getDestination());
506 args.add("destPos", arraycopy.getDestinationPosition());
507 args.add("length", arraycopy.getLength());
508 args.addConst("counters", counters);
509 instantiate(args, arraycopy);
510 }
511
512 private static boolean canBeArray(ResolvedJavaType type) {
513 return type == null || type.isJavaLangObject() || type.isArray();
514 }
515
516 public static JavaKind selectComponentKind(BasicArrayCopyNode arraycopy) {
517 ResolvedJavaType srcType = StampTool.typeOrNull(arraycopy.getSource().stamp(NodeView.DEFAULT));
518 ResolvedJavaType destType = StampTool.typeOrNull(arraycopy.getDestination().stamp(NodeView.DEFAULT));
519
520 if (srcType == null || !srcType.isArray() || destType == null || !destType.isArray()) {
521 return null;
522 }
523 if (!destType.getComponentType().isAssignableFrom(srcType.getComponentType())) {
524 return null;
525 }
526 if (!arraycopy.isExact()) {
527 return null;
528 }
529 return srcType.getComponentType().getJavaKind();
530 }
531
532 private static boolean shouldUnroll(ValueNode length) {
533 return length.isConstant() && length.asJavaConstant().asInt() <= 8 && length.asJavaConstant().asInt() != 0;
534 }
535
536 /**
537 * Instantiate the snippet template and fix up the FrameState of any Invokes of
538 * System.arraycopy and propagate the captured bci in the ArrayCopySlowPathNode.
539 *
540 * @param args
541 * @param arraycopy
542 */
543 private void instantiate(Arguments args, BasicArrayCopyNode arraycopy) {
544 StructuredGraph graph = arraycopy.graph();
545 SnippetTemplate template = template(arraycopy, args);
546 UnmodifiableEconomicMap<Node, Node> replacements = template.instantiate(providers.getMetaAccess(), arraycopy, SnippetTemplate.DEFAULT_REPLACER, args, false);
547 for (Node originalNode : replacements.getKeys()) {
548 if (originalNode instanceof InvokeNode) {
549 InvokeNode invoke = (InvokeNode) replacements.get(originalNode);
550 assert invoke.asNode().graph() == graph;
551 CallTargetNode call = invoke.callTarget();
552
553 if (!call.targetMethod().equals(originalArraycopy)) {
554 throw new GraalError("unexpected invoke %s in snippet", call.targetMethod());
555 }
556 // Here we need to fix the bci of the invoke
557 InvokeNode newInvoke = invoke.replaceWithNewBci(arraycopy.getBci());
558 newInvoke.setStateDuring(null);
559 newInvoke.setStateAfter(null);
560 if (arraycopy.stateDuring() != null) {
561 newInvoke.setStateDuring(arraycopy.stateDuring());
562 } else {
563 assert arraycopy.stateAfter() != null : arraycopy;
564 newInvoke.setStateAfter(arraycopy.stateAfter());
565 }
566 } else if (originalNode instanceof InvokeWithExceptionNode) {
567 throw new GraalError("unexpected invoke with exception %s in snippet", originalNode);
568 } else if (originalNode instanceof ArrayCopyWithSlowPathNode) {
569 ArrayCopyWithSlowPathNode slowPath = (ArrayCopyWithSlowPathNode) replacements.get(originalNode);
570 assert arraycopy.stateAfter() != null : arraycopy;
571 assert slowPath.stateAfter() == arraycopy.stateAfter();
572 slowPath.setBci(arraycopy.getBci());
573 }
574 }
575 GraphUtil.killCFG(arraycopy);
576 }
577
578 private ResolvedJavaMethod originalArraycopy() throws GraalError {
579 if (originalArraycopy == null) {
580 Method method;
581 try {
582 method = System.class.getDeclaredMethod("arraycopy", Object.class, int.class, Object.class, int.class, int.class);
583 } catch (NoSuchMethodException | SecurityException e) {
584 throw new GraalError(e);
585 }
586 originalArraycopy = providers.getMetaAccess().lookupJavaMethod(method);
587 }
588 return originalArraycopy;
589 }
590 }
591 }