CFA merge for definition / initialization : more accurate handling of unknown variables #KT-13969 Fixed

(cherry picked from commit 4a96589)

compiler/frontend/src/org/jetbrains/kotlin/cfg/PseudocodeTraverser.kt

@@ -63,7 +63,6 @@ fun <I : ControlFlowInfo<*>> Pseudocode.collectData(
         initialInfo: I
 ): Map<Instruction, Edges<I>> {
     val edgesMap = LinkedHashMap<Instruction, Edges<I>>()
-    initializeEdgesMap(edgesMap, initialInfo)
     edgesMap.put(getStartInstruction(traversalOrder), Edges(initialInfo, initialInfo))
 
     val changed = BooleanArray(1)
@@ -77,20 +76,6 @@ fun <I : ControlFlowInfo<*>> Pseudocode.collectData(
     return edgesMap
 }
 
-private fun <I> Pseudocode.initializeEdgesMap(
-        edgesMap: MutableMap<Instruction, Edges<I>>,
-        initialInfo: I
-) {
-    val instructions = instructions
-    val initialEdge = Edges(initialInfo, initialInfo)
-    for (instruction in instructions) {
-        edgesMap.put(instruction, initialEdge)
-        if (instruction is LocalFunctionDeclarationInstruction) {
-            instruction.body.initializeEdgesMap(edgesMap, initialInfo)
-        }
-    }
-}
-
 private fun <I : ControlFlowInfo<*>> Pseudocode.collectDataFromSubgraph(
         traversalOrder: TraversalOrder,
         mergeDataWithLocalDeclarations: Boolean,

compiler/frontend/src/org/jetbrains/kotlin/cfg/PseudocodeVariablesData.kt

@@ -221,12 +221,10 @@ class PseudocodeVariablesData(val pseudocode: Pseudocode, private val bindingCon
                 var initState: InitState? = null
                 var isDeclared = true
                 for (edgeData in incomingEdgesData) {
-                    val varControlFlowState = edgeData[variable]
-                    if (varControlFlowState != null) {
-                        initState = initState?.merge(varControlFlowState.initState) ?: varControlFlowState.initState
-                        if (!varControlFlowState.isDeclared) {
-                            isDeclared = false
-                        }
+                    val varControlFlowState = edgeData[variable] ?: VariableControlFlowState.create(isInitialized = false)
+                    initState = initState?.merge(varControlFlowState.initState) ?: varControlFlowState.initState
+                    if (!varControlFlowState.isDeclared) {
+                        isDeclared = false
                     }
                 }
                 if (initState == null) {