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63 lines
1.8 KiB
Swift
63 lines
1.8 KiB
Swift
//===--- PRNG.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) 2014 - 2015 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 http://swift.org/LICENSE.txt for license information
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// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
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//
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//===----------------------------------------------------------------------===//
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import SwiftShims
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@inline(never) @_semantics("stdlib_binary_only") // Hide the libbsd dependency
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public func rand32() -> UInt32 {
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return arc4random()
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}
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@inline(never) @_semantics("stdlib_binary_only") // Hide the libbsd dependency
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public func rand32(exclusiveUpperBound limit: UInt32) -> UInt32 {
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return arc4random_uniform(limit)
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}
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@inline(never) @_semantics("stdlib_binary_only") // Hide the libbsd dependency
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public func rand64() -> UInt64 {
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return (UInt64(arc4random()) << 32) | UInt64(arc4random())
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}
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public func randInt() -> Int {
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#if arch(i386) || arch(arm)
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return Int(Int32(bitPattern: rand32()))
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#elseif arch(x86_64) || arch(arm64)
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return Int(Int64(bitPattern: rand64()))
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#else
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fatalError("unimplemented")
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#endif
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}
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public func randArray64(count: Int) -> _UnitTestArray<UInt64> {
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var result = _UnitTestArray<UInt64>(count: count, repeatedValue: 0)
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for i in result.indices {
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result[i] = rand64()
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}
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return result
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}
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public func randArray(count: Int) -> [Int] {
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var result = [Int](count: count, repeatedValue: 0)
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for i in result.indices {
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result[i] = randInt()
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}
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return result
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}
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public func pickRandom<
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C : CollectionType where C.Index : RandomAccessIndexType
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>(c: C) -> C.Generator.Element {
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let i = Int(rand32(exclusiveUpperBound: numericCast(c.count())))
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return c[advance(c.startIndex, numericCast(i))]
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}
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