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