FIR: fork flow on function entry, restore receivers on exit

^KT-52680 Fixed

compiler/testData/diagnostics/tests/smartCasts/implicitReceiverAcrossFunctions.fir.kt

@@ -0,0 +1,24 @@
+interface I {
+    val prop: Int
+}
+
+open class A {
+    fun f1() {
+        this as I
+        prop
+    }
+
+    fun f2() {
+        <!UNRESOLVED_REFERENCE!>prop<!>
+    }
+}
+
+open class B {
+    fun f() {
+        {
+            this as I
+            prop
+        }
+        <!UNRESOLVED_REFERENCE!>prop<!>
+    }
+}

compiler/testData/diagnostics/tests/smartCasts/implicitReceiverAcrossFunctions.kt

@@ -0,0 +1,24 @@
+interface I {
+    val prop: Int
+}
+
+open class A {
+    fun f1() {
+        this as I
+        <!DEBUG_INFO_IMPLICIT_RECEIVER_SMARTCAST!>prop<!>
+    }
+
+    fun f2() {
+        <!UNRESOLVED_REFERENCE!>prop<!>
+    }
+}
+
+open class B {
+    fun f() {
+        {
+            this as I
+            <!DEBUG_INFO_IMPLICIT_RECEIVER_SMARTCAST!>prop<!>
+        }
+        <!UNRESOLVED_REFERENCE!>prop<!>
+    }
+}

compiler/testData/diagnostics/tests/smartCasts/implicitReceiverAcrossFunctions.txt

@@ -0,0 +1,25 @@
+package
+
+public open class A {
+    public constructor A()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final fun f1(): kotlin.Unit
+    public final fun f2(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public open class B {
+    public constructor B()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final fun f(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface I {
+    public abstract val prop: kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/smartCasts/loops/doWhileLiteral.fir.kt

@@ -1,10 +0,0 @@
-fun x(): Boolean { return true }
-
-public fun foo(p: String?): Int {
-    // Exotic variant with unused literal
-    do { ->
-        p!!.length
-    } while (!x())
-    // Literal is not called so p.length is unsafe
-    return p.length
-}

compiler/testData/diagnostics/tests/smartCasts/loops/doWhileLiteral.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 fun x(): Boolean { return true }
 
 public fun foo(p: String?): Int {