1/*
2 * Copyright (c) 2012, 2015, 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 */
23package org.graalvm.compiler.hotspot.stubs;
24
25import static org.graalvm.compiler.hotspot.GraalHotSpotVMConfig.INJECTED_VMCONFIG;
26import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.HEAP_END_LOCATION;
27import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.HEAP_TOP_LOCATION;
28import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.PROTOTYPE_MARK_WORD_LOCATION;
29import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.TLAB_FAST_REFILL_WASTE_LOCATION;
30import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.TLAB_NOF_REFILLS_LOCATION;
31import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.TLAB_REFILL_WASTE_LIMIT_LOCATION;
32import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.TLAB_SIZE_LOCATION;
33import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.TLAB_SLOW_ALLOCATIONS_LOCATION;
34import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.TLAB_THREAD_ALLOCATED_BYTES_LOCATION;
35import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.arrayBaseOffset;
36import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.getAndClearObjectResult;
37import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.initializeTlab;
38import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.isInstanceKlassFullyInitialized;
39import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.readLayoutHelper;
40import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.log2WordSize;
41import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.prototypeMarkWordOffset;
42import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.readTlabEnd;
43import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.readTlabStart;
44import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.readTlabTop;
45import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.registerAsWord;
46import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.threadAllocatedBytesOffset;
47import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.threadTlabSizeOffset;
48import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.tlabAlignmentReserveInHeapWords;
49import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.tlabFastRefillWasteOffset;
50import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.tlabIntArrayMarkWord;
51import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.tlabNumberOfRefillsOffset;
52import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.tlabRefillWasteIncrement;
53import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.tlabRefillWasteLimitOffset;
54import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.tlabSlowAllocationsOffset;
55import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.tlabStats;
56import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.useG1GC;
57import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.useTLAB;
58import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.wordSize;
59import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.writeTlabTop;
60import static org.graalvm.compiler.hotspot.stubs.StubUtil.handlePendingException;
61import static org.graalvm.compiler.hotspot.stubs.StubUtil.newDescriptor;
62import static org.graalvm.compiler.hotspot.stubs.StubUtil.printf;
63import static org.graalvm.compiler.hotspot.stubs.StubUtil.verifyObject;
64import static org.graalvm.compiler.nodes.extended.BranchProbabilityNode.FAST_PATH_PROBABILITY;
65import static org.graalvm.compiler.nodes.extended.BranchProbabilityNode.probability;
66
67import org.graalvm.compiler.api.replacements.Fold;
68import org.graalvm.compiler.api.replacements.Snippet;
69import org.graalvm.compiler.api.replacements.Snippet.ConstantParameter;
70import org.graalvm.compiler.core.common.spi.ForeignCallDescriptor;
71import org.graalvm.compiler.graph.Node.ConstantNodeParameter;
72import org.graalvm.compiler.graph.Node.NodeIntrinsic;
73import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage;
74import org.graalvm.compiler.hotspot.meta.HotSpotProviders;
75import org.graalvm.compiler.hotspot.nodes.GraalHotSpotVMConfigNode;
76import org.graalvm.compiler.hotspot.nodes.StubForeignCallNode;
77import org.graalvm.compiler.hotspot.nodes.type.KlassPointerStamp;
78import org.graalvm.compiler.hotspot.replacements.NewObjectSnippets;
79import org.graalvm.compiler.hotspot.word.KlassPointer;
80import org.graalvm.compiler.nodes.ConstantNode;
81import org.graalvm.compiler.options.OptionValues;
82import org.graalvm.compiler.word.Word;
83import org.graalvm.word.WordFactory;
84
85import jdk.vm.ci.code.Register;
86import jdk.vm.ci.hotspot.HotSpotResolvedObjectType;
87import jdk.vm.ci.meta.JavaKind;
88
89/**
90 * Stub implementing the fast path for TLAB refill during instance class allocation. This stub is
91 * called from the {@linkplain NewObjectSnippets inline} allocation code when TLAB allocation fails.
92 * If this stub fails to refill the TLAB or allocate the object, it calls out to the HotSpot C++
93 * runtime for to complete the allocation.
94 */
95public class NewInstanceStub extends SnippetStub {
96
97    public NewInstanceStub(OptionValues options, HotSpotProviders providers, HotSpotForeignCallLinkage linkage) {
98        super("newInstance", options, providers, linkage);
99    }
100
101    @Override
102    protected Object[] makeConstArgs() {
103        HotSpotResolvedObjectType intArrayType = (HotSpotResolvedObjectType) providers.getMetaAccess().lookupJavaType(int[].class);
104        int count = method.getSignature().getParameterCount(false);
105        Object[] args = new Object[count];
106        assert checkConstArg(1, "intArrayHub");
107        assert checkConstArg(2, "threadRegister");
108        assert checkConstArg(3, "options");
109        args[1] = ConstantNode.forConstant(KlassPointerStamp.klassNonNull(), intArrayType.klass(), null);
110        args[2] = providers.getRegisters().getThreadRegister();
111        args[3] = options;
112        return args;
113    }
114
115    private static Word allocate(Word thread, int size) {
116        Word top = readTlabTop(thread);
117        Word end = readTlabEnd(thread);
118        Word newTop = top.add(size);
119        /*
120         * this check might lead to problems if the TLAB is within 16GB of the address space end
121         * (checked in c++ code)
122         */
123        if (probability(FAST_PATH_PROBABILITY, newTop.belowOrEqual(end))) {
124            writeTlabTop(thread, newTop);
125            return top;
126        }
127        return WordFactory.zero();
128    }
129
130    @Fold
131    static boolean logging(OptionValues options) {
132        return StubOptions.TraceNewInstanceStub.getValue(options);
133    }
134
135    /**
136     * Re-attempts allocation after an initial TLAB allocation failed or was skipped (e.g., due to
137     * -XX:-UseTLAB).
138     *
139     * @param hub the hub of the object to be allocated
140     * @param intArrayHub the hub for {@code int[].class}
141     */
142    @Snippet
143    private static Object newInstance(KlassPointer hub, @ConstantParameter KlassPointer intArrayHub, @ConstantParameter Register threadRegister, @ConstantParameter OptionValues options) {
144        /*
145         * The type is known to be an instance so Klass::_layout_helper is the instance size as a
146         * raw number
147         */
148        Word thread = registerAsWord(threadRegister);
149        boolean inlineContiguousAllocationSupported = GraalHotSpotVMConfigNode.inlineContiguousAllocationSupported();
150        if (!forceSlowPath(options) && inlineContiguousAllocationSupported) {
151            if (isInstanceKlassFullyInitialized(hub)) {
152                int sizeInBytes = readLayoutHelper(hub);
153                Word memory = refillAllocate(thread, intArrayHub, sizeInBytes, logging(options));
154                if (memory.notEqual(0)) {
155                    Word prototypeMarkWord = hub.readWord(prototypeMarkWordOffset(INJECTED_VMCONFIG), PROTOTYPE_MARK_WORD_LOCATION);
156                    NewObjectSnippets.formatObjectForStub(hub, sizeInBytes, memory, prototypeMarkWord);
157                    return verifyObject(memory.toObject());
158                }
159            }
160        }
161
162        if (logging(options)) {
163            printf("newInstance: calling new_instance_c\n");
164        }
165
166        newInstanceC(NEW_INSTANCE_C, thread, hub);
167        handlePendingException(thread, true);
168        return verifyObject(getAndClearObjectResult(thread));
169    }
170
171    /**
172     * Attempts to refill the current thread's TLAB and retries the allocation.
173     *
174     * @param intArrayHub the hub for {@code int[].class}
175     * @param sizeInBytes the size of the allocation
176     * @param log specifies if logging is enabled
177     *
178     * @return the newly allocated, uninitialized chunk of memory, or {@link WordFactory#zero()} if
179     *         the operation was unsuccessful
180     */
181    static Word refillAllocate(Word thread, KlassPointer intArrayHub, int sizeInBytes, boolean log) {
182        // If G1 is enabled, the "eden" allocation space is not the same always
183        // and therefore we have to go to slowpath to allocate a new TLAB.
184        if (useG1GC(INJECTED_VMCONFIG)) {
185            return WordFactory.zero();
186        }
187        if (!useTLAB(INJECTED_VMCONFIG)) {
188            return edenAllocate(WordFactory.unsigned(sizeInBytes), log);
189        }
190        Word intArrayMarkWord = WordFactory.unsigned(tlabIntArrayMarkWord(INJECTED_VMCONFIG));
191        int alignmentReserveInBytes = tlabAlignmentReserveInHeapWords(INJECTED_VMCONFIG) * wordSize();
192
193        Word top = readTlabTop(thread);
194        Word end = readTlabEnd(thread);
195
196        // calculate amount of free space
197        long tlabFreeSpaceInBytes = end.subtract(top).rawValue();
198
199        if (log) {
200            printf("refillTLAB: thread=%p\n", thread.rawValue());
201            printf("refillTLAB: top=%p\n", top.rawValue());
202            printf("refillTLAB: end=%p\n", end.rawValue());
203            printf("refillTLAB: tlabFreeSpaceInBytes=%ld\n", tlabFreeSpaceInBytes);
204        }
205
206        long tlabFreeSpaceInWords = tlabFreeSpaceInBytes >>> log2WordSize();
207
208        // Retain TLAB and allocate object in shared space if
209        // the amount free in the TLAB is too large to discard.
210        Word refillWasteLimit = thread.readWord(tlabRefillWasteLimitOffset(INJECTED_VMCONFIG), TLAB_REFILL_WASTE_LIMIT_LOCATION);
211        if (tlabFreeSpaceInWords <= refillWasteLimit.rawValue()) {
212            if (tlabStats(INJECTED_VMCONFIG)) {
213                // increment number of refills
214                thread.writeInt(tlabNumberOfRefillsOffset(INJECTED_VMCONFIG), thread.readInt(tlabNumberOfRefillsOffset(INJECTED_VMCONFIG), TLAB_NOF_REFILLS_LOCATION) + 1, TLAB_NOF_REFILLS_LOCATION);
215                if (log) {
216                    printf("thread: %p -- number_of_refills %d\n", thread.rawValue(), thread.readInt(tlabNumberOfRefillsOffset(INJECTED_VMCONFIG), TLAB_NOF_REFILLS_LOCATION));
217                }
218                // accumulate wastage
219                int wastage = thread.readInt(tlabFastRefillWasteOffset(INJECTED_VMCONFIG), TLAB_FAST_REFILL_WASTE_LOCATION) + (int) tlabFreeSpaceInWords;
220                if (log) {
221                    printf("thread: %p -- accumulated wastage %d\n", thread.rawValue(), wastage);
222                }
223                thread.writeInt(tlabFastRefillWasteOffset(INJECTED_VMCONFIG), wastage, TLAB_FAST_REFILL_WASTE_LOCATION);
224            }
225
226            // if TLAB is currently allocated (top or end != null) then
227            // fill [top, end + alignment_reserve) with array object
228            if (top.notEqual(0)) {
229                int headerSize = arrayBaseOffset(JavaKind.Int);
230                // just like the HotSpot assembler stubs, assumes that tlabFreeSpaceInInts fits in
231                // an int
232                int tlabFreeSpaceInInts = (int) tlabFreeSpaceInBytes >>> 2;
233                int length = ((alignmentReserveInBytes - headerSize) >>> 2) + tlabFreeSpaceInInts;
234                NewObjectSnippets.formatArray(intArrayHub, 0, length, headerSize, top, intArrayMarkWord, false, false, null);
235
236                long allocated = thread.readLong(threadAllocatedBytesOffset(INJECTED_VMCONFIG), TLAB_THREAD_ALLOCATED_BYTES_LOCATION);
237                allocated = allocated + top.subtract(readTlabStart(thread)).rawValue();
238                thread.writeLong(threadAllocatedBytesOffset(INJECTED_VMCONFIG), allocated, TLAB_THREAD_ALLOCATED_BYTES_LOCATION);
239            }
240
241            // refill the TLAB with an eden allocation
242            Word tlabRefillSizeInWords = thread.readWord(threadTlabSizeOffset(INJECTED_VMCONFIG), TLAB_SIZE_LOCATION);
243            Word tlabRefillSizeInBytes = tlabRefillSizeInWords.multiply(wordSize());
244            // allocate new TLAB, address returned in top
245            top = edenAllocate(tlabRefillSizeInBytes, log);
246            if (top.notEqual(0)) {
247                end = top.add(tlabRefillSizeInBytes.subtract(alignmentReserveInBytes));
248                initializeTlab(thread, top, end);
249
250                return NewInstanceStub.allocate(thread, sizeInBytes);
251            } else {
252                return WordFactory.zero();
253            }
254        } else {
255            // Retain TLAB
256            Word newRefillWasteLimit = refillWasteLimit.add(tlabRefillWasteIncrement(INJECTED_VMCONFIG));
257            thread.writeWord(tlabRefillWasteLimitOffset(INJECTED_VMCONFIG), newRefillWasteLimit, TLAB_REFILL_WASTE_LIMIT_LOCATION);
258            if (log) {
259                printf("refillTLAB: retaining TLAB - newRefillWasteLimit=%p\n", newRefillWasteLimit.rawValue());
260            }
261
262            if (tlabStats(INJECTED_VMCONFIG)) {
263                thread.writeInt(tlabSlowAllocationsOffset(INJECTED_VMCONFIG), thread.readInt(tlabSlowAllocationsOffset(INJECTED_VMCONFIG), TLAB_SLOW_ALLOCATIONS_LOCATION) + 1,
264                                TLAB_SLOW_ALLOCATIONS_LOCATION);
265            }
266
267            return edenAllocate(WordFactory.unsigned(sizeInBytes), log);
268        }
269    }
270
271    /**
272     * Attempts to allocate a chunk of memory from Eden space.
273     *
274     * @param sizeInBytes the size of the chunk to allocate
275     * @param log specifies if logging is enabled
276     * @return the allocated chunk or {@link WordFactory#zero()} if allocation fails
277     */
278    public static Word edenAllocate(Word sizeInBytes, boolean log) {
279        final long heapTopRawAddress = GraalHotSpotVMConfigNode.heapTopAddress();
280        final long heapEndRawAddress = GraalHotSpotVMConfigNode.heapEndAddress();
281
282        Word heapTopAddress = WordFactory.unsigned(heapTopRawAddress);
283        Word heapEndAddress = WordFactory.unsigned(heapEndRawAddress);
284
285        while (true) {
286            Word heapTop = heapTopAddress.readWord(0, HEAP_TOP_LOCATION);
287            Word newHeapTop = heapTop.add(sizeInBytes);
288            if (newHeapTop.belowOrEqual(heapTop)) {
289                return WordFactory.zero();
290            }
291
292            Word heapEnd = heapEndAddress.readWord(0, HEAP_END_LOCATION);
293            if (newHeapTop.aboveThan(heapEnd)) {
294                return WordFactory.zero();
295            }
296            if (heapTopAddress.logicCompareAndSwapWord(0, heapTop, newHeapTop, HEAP_TOP_LOCATION)) {
297                return heapTop;
298            }
299        }
300    }
301
302    @Fold
303    static boolean forceSlowPath(OptionValues options) {
304        return StubOptions.ForceUseOfNewInstanceStub.getValue(options);
305    }
306
307    public static final ForeignCallDescriptor NEW_INSTANCE_C = newDescriptor(NewInstanceStub.class, "newInstanceC", void.class, Word.class, KlassPointer.class);
308
309    @NodeIntrinsic(StubForeignCallNode.class)
310    public static native void newInstanceC(@ConstantNodeParameter ForeignCallDescriptor newInstanceC, Word thread, KlassPointer hub);
311}
312