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// RUN: %target-run-simple-swift( -Xfrontend -sil-verify-all -Xfrontend -disable-availability-checking %import-libdispatch -parse-as-library)
// REQUIRES: executable_test
// REQUIRES: concurrency
// REQUIRES: libdispatch
// rdar://76038845
// REQUIRES: concurrency_runtime
// UNSUPPORTED: back_deployment_runtime
@available(SwiftStdlib 5.1, *)
actor Counter {
private var value = 0
private let scratchBuffer: UnsafeMutableBufferPointer<Int>
init(maxCount: Int) {
scratchBuffer = .allocate(capacity: maxCount)
scratchBuffer.initialize(repeating: 0)
}
func next() -> Int {
let current = value
// Make sure we haven't produced this value before
assert(scratchBuffer[current] == 0)
scratchBuffer[current] = 1
value = value + 1
return current
}
deinit {
for i in 0..<value {
assert(scratchBuffer[i] == 1)
}
}
}
// Produce a random priority.
nonisolated var randomPriority: TaskPriority? {
let priorities: [TaskPriority?] = [ .background, .low, .medium, .high, nil ]
return priorities.randomElement()!
}
@available(SwiftStdlib 5.1, *)
func worker(identity: Int, counters: [Counter], numIterations: Int) async {
for i in 0..<numIterations {
let counterIndex = Int.random(in: 0 ..< counters.count)
let counter = counters[counterIndex]
let nextValue = await counter.next()
print("Worker \(identity) calling counter \(counterIndex) produced \(nextValue)")
}
}
@available(SwiftStdlib 5.1, *)
func runTest(numCounters: Int, numWorkers: Int, numIterations: Int) async {
// Create counter actors.
var counters: [Counter] = []
for i in 0..<numCounters {
counters.append(Counter(maxCount: numWorkers * numIterations))
}
// Create a bunch of worker threads.
var workers: [Task.Handle<Void, Error>] = []
for i in 0..<numWorkers {
workers.append(
Task.detached(priority: randomPriority) { [counters] in
try! await Task.sleep(nanoseconds: UInt64.random(in: 0..<100) * 1_000_000)
await worker(identity: i, counters: counters, numIterations: numIterations)
}
)
}
// Wait until all of the workers have finished.
for worker in workers {
try! await worker.get()
}
print("DONE!")
}
@available(SwiftStdlib 5.1, *)
@main struct Main {
static func main() async {
// Useful for debugging: specify counter/worker/iteration counts
let args = CommandLine.arguments
let counters = args.count >= 2 ? Int(args[1])! : 10
let workers = args.count >= 3 ? Int(args[2])! : 100
let iterations = args.count >= 4 ? Int(args[3])! : 1000
print("counters: \(counters), workers: \(workers), iterations: \(iterations)")
await runTest(numCounters: counters, numWorkers: workers, numIterations: iterations)
}
}
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