Daniel Andersson
17a6b944d1
Thread barrier with:
* fixed (at construction) number n of participating threads {T1,T2,T3,...,Tn}
* unknown number of rounds.
Requirements:
* there is some R such that each participating thread makes
R calls to Sync() followed by its one and only call to Exit().
Guarantees:
* for any two threads Ti and Tj and round number r <= R,
everything done by Ti before its r'th call to Sync() happens before
everything done by Tj after its r'th call to Sync().
Note:
* it's not required that the thread that constructs the barrier participates.
BUG=
Review URL: https://codereview.chromium.org//1337943004 .
38 lines
771 B
C++
38 lines
771 B
C++
// Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file
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// for details. All rights reserved. Use of this source code is governed by a
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// BSD-style license that can be found in the LICENSE file.
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#ifndef VM_RANDOM_H_
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#define VM_RANDOM_H_
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#include "vm/globals.h"
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#include "vm/allocation.h"
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namespace dart {
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class Random {
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public:
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Random();
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// Seed must be non-zero.
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explicit Random(uint64_t seed);
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~Random();
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uint32_t NextUInt32();
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uint64_t NextUInt64() {
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return (static_cast<uint64_t>(NextUInt32()) << 32) |
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static_cast<uint64_t>(NextUInt32());
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}
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private:
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void NextState();
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void Initialize(uint64_t seed);
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uint64_t _state;
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DISALLOW_COPY_AND_ASSIGN(Random);
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};
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} // namespace dart
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#endif // VM_RANDOM_H_
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