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b189084f4f
* Add a Unicode data generator util package * Add a common GenUtils library * Use string methods for reading/writing files
51 lines
1.2 KiB
Swift
51 lines
1.2 KiB
Swift
//===----------------------------------------------------------------------===//
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//
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// This source file is part of the Swift.org open source project
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//
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// Copyright (c) 2021 Apple Inc. and the Swift project authors
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// Licensed under Apache License v2.0 with Runtime Library Exception
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//
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// See https://swift.org/LICENSE.txt for license information
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// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
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//
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//===----------------------------------------------------------------------===//
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func hash(_ key: UInt64, _ n: UInt64, seed: UInt64) -> UInt64 {
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let key = key | (n << 32)
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let hash = UInt64(murmur3(key, seed: UInt32(seed)))
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return hash % n
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}
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func scramble(_ key: UInt32) -> UInt32 {
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var key = key
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key &*= 0xCC9E2D51
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key = (key << 15) | (key >> 17)
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key &*= 0x1B873593
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return key
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}
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func murmur3(_ key: UInt64, seed: UInt32) -> UInt32 {
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var hash = seed
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var k: UInt32
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var key = key
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for _ in 0 ..< 2 {
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k = UInt32((key << 32) >> 32)
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key >>= 32
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hash ^= scramble(k)
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hash = (hash << 13) | (hash >> 19)
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hash = hash &* 5 &+ 0xE6546B64
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}
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hash ^= 8
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hash ^= hash >> 16
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hash &*= 0x85EBCA6B
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hash ^= hash >> 13
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hash &*= 0xC2B2AE35
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hash ^= hash >> 16
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return hash
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}
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