FIR DFA: correct exit node retrieval when a safe call is the last expression

^KT-44699 Fixed

compiler/fir/analysis-tests/testData/resolve/callResolution/safeCallOnTypeAlias.fir.txt

@@ -1,7 +1,7 @@
 FILE: safeCallOnTypeAlias.kt
     public final typealias MyTypeAlias = R|() -> kotlin/String?|
     public final fun foo(x: R|MyTypeAlias|): R|kotlin/Unit| {
-        R|<local>/x|?.{ $subj$.R|kotlin/let|<R|() -> kotlin/String?|, R|kotlin/String|>(<L> = let@fun <anonymous>(y: R|() -> kotlin/String?|): R|kotlin/String| <kind=EXACTLY_ONCE>  {
+        R|<local>/x|?.{ $subj$.R|kotlin/let|<R|() -> kotlin/String?|, R|kotlin/String?|>(<L> = let@fun <anonymous>(y: R|() -> kotlin/String?|): R|kotlin/String?| <kind=EXACTLY_ONCE>  {
             ^ R|<local>/y|.R|SubstitutionOverride<kotlin/Function0.invoke: R|kotlin/String?|>|()?.{ $subj$.R|kotlin/let|<R|kotlin/String|, R|kotlin/String|>(<L> = let@fun <anonymous>(result: R|kotlin/String|): R|kotlin/String| <kind=EXACTLY_ONCE>  {
                 ^ R|/bar|(R|<local>/result|)
             }

compiler/fir/analysis-tests/testData/resolve/inference/coercionToUnitWithEarlyReturn.fir.txt

@@ -11,7 +11,7 @@ FILE: coercionToUnitWithEarlyReturn.kt
     public final fun foo(x: R|() -> kotlin/Unit|): R|kotlin/Unit| {
     }
     public final fun main(x: R|A?|): R|kotlin/Unit| {
-        lval lambda: R|() -> kotlin/Unit| = l@fun <anonymous>(): R|kotlin/Unit| {
+        lval lambda: R|() -> kotlin/Unit?| = l@fun <anonymous>(): R|kotlin/Unit?| {
             when () {
                 ==(R|<local>/x|?.{ $subj$.R|kotlin/Any.hashCode|() }, Int(0)) ->  {
                     ^@l Unit
@@ -21,5 +21,5 @@ FILE: coercionToUnitWithEarlyReturn.kt
             ^ R|<local>/x|?.{ $subj$.R|/A.unit|() }
         }
 
-        R|/foo|(R|<local>/lambda|)
+        <Inapplicable(INAPPLICABLE): /foo>#(R|<local>/lambda|)
     }

compiler/fir/analysis-tests/testData/resolve/inference/coercionToUnitWithEarlyReturn.kt

@@ -15,5 +15,5 @@ fun main(x: A?) {
     }
 
     // lambda has a type (() -> Unit?)
-    foo(lambda)
+    <!INAPPLICABLE_CANDIDATE{LT}!><!INAPPLICABLE_CANDIDATE{PSI}!>foo<!>(lambda)<!>
 }

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/cfg/ControlFlowGraphBuilder.kt

@@ -133,7 +133,6 @@ class ControlFlowGraphBuilder {
 
         fun CFGNode<*>.extractArgument(): FirElement? = when (this) {
             is FunctionEnterNode, is TryMainBlockEnterNode, is CatchClauseEnterNode -> null
-            is ExitSafeCallNode -> lastPreviousNode.extractArgument()
             is StubNode, is BlockExitNode -> firstPreviousNode.extractArgument()
             else -> fir.extractArgument()
         }
@@ -1090,8 +1089,9 @@ class ControlFlowGraphBuilder {
          *   lastNode -> exitNode
          * instead of
          *   lastNode -> enterNode -> exitNode
-         * because of we need to fork flow on `enterNode`, so `exitNode`
+         * because we need to fork flow before `enterNode`, so `exitNode`
          *   will have unchanged flow from `lastNode`
+         *   which corresponds to a path with nullable receiver.
          */
         val lastNode = lastNodes.pop()
         val enterNode = createEnterSafeCallNode(safeCall)
@@ -1104,6 +1104,12 @@ class ControlFlowGraphBuilder {
     }
 
     fun exitSafeCall(): ExitSafeCallNode {
+        // There will be two paths towards this exit safe call node:
+        // one from the node prior to the enclosing safe call, and
+        // the other from the selector part in the enclosing safe call.
+        // Note that *neither* points to the safe call directly.
+        // So, when it comes to the real exit of the enclosing block/function,
+        // the safe call bound to this exit safe call node should be retrieved.
         return exitSafeCallNodes.pop().also {
             addNewSimpleNode(it)
             it.updateDeadStatus()

compiler/testData/diagnostics/testsWithStdLib/buildLazyValueForMap.fir.kt

@@ -1,23 +0,0 @@
-// !WITH_NEW_INFERENCE
-
-interface ClassId
-
-interface JavaAnnotation {
-    val classId: ClassId?
-}
-
-interface JavaAnnotationOwner {
-    val annotations: Collection<JavaAnnotation>
-}
-
-interface MapBasedJavaAnnotationOwner : JavaAnnotationOwner {
-    val annotationsByFqNameHash: Map<Int?, JavaAnnotation>
-}
-
-fun JavaAnnotationOwner.buildLazyValueForMap() = lazy {
-    annotations.associateBy { it.classId?.hashCode() }
-}
-
-abstract class BinaryJavaMethodBase(): MapBasedJavaAnnotationOwner {
-    override val <!PROPERTY_TYPE_MISMATCH_ON_OVERRIDE!>annotationsByFqNameHash<!> by buildLazyValueForMap()
-}

compiler/testData/diagnostics/testsWithStdLib/buildLazyValueForMap.kt

@@ -1,3 +1,5 @@
+// FIR_IDENTICAL
+
 interface ClassId
 
 interface JavaAnnotation {