Freezing: fixed test and added stress test

backend.native/tests/build.gradle

@@ -623,11 +623,16 @@ task freeze0(type: RunKonanTest) {
 
 task freeze1(type: RunKonanTest) {
     disabled = (project.testTarget == 'wasm32') // No exceptions on WASM.
-    goldValue = "OK, cannot freeze cyclic\n"+
-                "OK, cannot mutate frozen\n"
+    goldValue = "OK, cannot mutate frozen\n"
     source = "runtime/workers/freeze1.kt"
 }
 
+task freeze_stress(type: RunKonanTest) {
+    disabled = (project.testTarget == 'wasm32') // No exceptions on WASM.
+    goldValue = "OK\n"
+    source = "runtime/workers/freeze_stress.kt"
+}
+
 task superFunCall(type: RunKonanTest) {
     goldValue = "<fun:C><fun:C1>\n<fun:C><fun:C3>\n"
     source = "codegen/basics/superFunCall.kt"

backend.native/tests/runtime/workers/freeze1.kt

@@ -43,11 +43,7 @@ fun makeDiamond(): Node2 {
 }
 
 @Test fun runTest() {
-    try {
-        makeCycle(10).freeze()
-    } catch (e: FreezingException) {
-        println("OK, cannot freeze cyclic")
-    }
+    makeCycle(10).freeze()
 
     // Must be able to freeze diamond shaped graph.
     val diamond = makeDiamond().freeze()

backend.native/tests/runtime/workers/freeze_stress.kt

@@ -0,0 +1,145 @@
+package runtime.workers.freeze_stress
+
+import kotlin.test.*
+
+import konan.worker.*
+
+class Random(private var seed: Int) {
+    fun next(): Int {
+        seed = (1103515245 * seed + 12345) and 0x7fffffff
+        return seed
+    }
+
+    fun next(maxExclusiveValue: Int) = if (maxExclusiveValue == 0) 0 else next() % maxExclusiveValue
+
+    fun next(minInclusiveValue: Int, maxInclusiveValue: Int) =
+            minInclusiveValue + next(maxInclusiveValue - minInclusiveValue + 1)
+}
+
+class Node(val id: Int) {
+    var numberOfEdges = 0
+
+    lateinit var edge0: Node
+    lateinit var edge1: Node
+    lateinit var edge2: Node
+    lateinit var edge3: Node
+    lateinit var edge4: Node
+    lateinit var edge5: Node
+    lateinit var edge6: Node
+    lateinit var edge7: Node
+    lateinit var edge8: Node
+    lateinit var edge9: Node
+
+    fun addEdge(child: Node) {
+        when (numberOfEdges) {
+            0 -> edge0 = child
+            1 -> edge1 = child
+            2 -> edge2 = child
+            3 -> edge3 = child
+            4 -> edge4 = child
+            5 -> edge5 = child
+            6 -> edge6 = child
+            7 -> edge7 = child
+            8 -> edge8 = child
+            9 -> edge9 = child
+            else -> error("Too many edges")
+        }
+        ++numberOfEdges
+    }
+
+    fun getEdges(): List<Node> {
+        val result = mutableListOf<Node>()
+        if (numberOfEdges > 0) result += edge0
+        if (numberOfEdges > 1) result += edge1
+        if (numberOfEdges > 2) result += edge2
+        if (numberOfEdges > 3) result += edge3
+        if (numberOfEdges > 4) result += edge4
+        if (numberOfEdges > 5) result += edge5
+        if (numberOfEdges > 6) result += edge6
+        if (numberOfEdges > 7) result += edge7
+        if (numberOfEdges > 8) result += edge8
+        if (numberOfEdges > 9) result += edge9
+        return result
+    }
+}
+
+class Graph(val nodes: List<Node>, val roots: List<Node>)
+
+fun min(x: Int, y: Int) = if (x < y) x else y
+fun max(x: Int, y: Int) = if (x > y) x else y
+
+val random = Random(42)
+
+fun generate(condensationSize: Int, branchingFactor: Int, swellingFactor: Int): Graph {
+    var id = 0
+    val nodes = mutableListOf<Node>()
+
+    fun genDAG(n: Int): Node {
+        val node = Node(id++)
+        nodes += node
+        if (n == 1) return node
+        val numberOfChildren = random.next(1, min(n - 1, branchingFactor))
+        val used = BooleanArray(n)
+        val points = IntArray(numberOfChildren + 1)
+        points[0] = 0
+        points[numberOfChildren] = n - 1
+        used[0] = true
+        used[n - 1] = true
+        for (i in 1 until numberOfChildren) {
+            var p: Int
+            do {
+                p = random.next(1, n - 1)
+            } while (used[p])
+            used[p] = true
+            points[i] = p
+        }
+        points.sort()
+        for (i in 1..numberOfChildren) {
+            val childSize = points[i] - points[i - 1]
+            val child = genDAG(childSize)
+            if (random.next(2) == 0)
+                node.addEdge(child)
+            else
+                child.addEdge(node)
+        }
+        return node
+    }
+
+    genDAG(condensationSize)
+
+    val numberOfEnters = IntArray(condensationSize)
+    for (node in nodes)
+        for (edge in node.getEdges())
+            ++numberOfEnters[edge.id]
+    val roots = nodes.filter { numberOfEnters[it.id] == 0 }
+    for (i in 0 until condensationSize) {
+        val node = nodes[i]
+        val componentSize = random.next(1, swellingFactor)
+        if (componentSize == 1 && random.next(2) == 0)
+            continue
+        val component = Array(componentSize) {
+            if (it == 0) node else Node(id++).also { nodes += it }
+        }
+        for (j in 0 until componentSize)
+            component[j].addEdge(component[(j - 1 + componentSize) % componentSize])
+        val numberOfAdditionalEdges = random.next((componentSize + 1) / 2)
+        for (j in 0 until numberOfAdditionalEdges)
+            component[random.next(componentSize)].addEdge(component[random.next(componentSize)])
+    }
+
+    return Graph(nodes, roots)
+}
+
+fun freezeOneGraph() {
+    val graph = generate(100, 5, 20)
+    graph.roots.forEach { it.freeze() }
+    for (node in graph.nodes)
+        assert (node.isFrozen, { "All nodes should be frozen" })
+}
+
+@Test fun runTest() {
+    for (i in 0..1000) {
+        freezeOneGraph()
+    }
+    println("OK")
+}