1/*
2 * Copyright (c) 2016, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
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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 *
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24
25#ifndef SHARE_GC_G1_G1CONCURRENTMARKOBJARRAYPROCESSOR_HPP
26#define SHARE_GC_G1_G1CONCURRENTMARKOBJARRAYPROCESSOR_HPP
27
28#include "oops/oopsHierarchy.hpp"
29
30class G1CMTask;
31
32// Helper class to mark through large objArrays during marking in an efficient way.
33// Instead of pushing large object arrays, we push continuations onto the
34// mark stack. These continuations are identified by having their LSB set.
35// This allows incremental processing of large objects.
36class G1CMObjArrayProcessor {
37private:
38 // Reference to the task for doing the actual work.
39 G1CMTask* _task;
40
41 // Push the continuation at the given address onto the mark stack.
42 void push_array_slice(HeapWord* addr);
43
44 // Process (apply the closure) on the given continuation of the given objArray.
45 size_t process_array_slice(objArrayOop const obj, HeapWord* start_from, size_t remaining);
46public:
47 static bool should_be_sliced(oop obj);
48
49 G1CMObjArrayProcessor(G1CMTask* task) : _task(task) {
50 }
51
52 // Process the given continuation. Returns the number of words scanned.
53 size_t process_slice(HeapWord* slice);
54 // Start processing the given objArrayOop by scanning the header and pushing its
55 // continuation.
56 size_t process_obj(oop obj);
57};
58
59#endif // SHARE_GC_G1_G1CONCURRENTMARKOBJARRAYPROCESSOR_HPP
60