[FIR] Create CFG for files to track top-level property initialization

In order to properly analyze top-level property initialization, a
control-flow graph must be created for FirFiles. This change adds the
foundation for the file CFG and updates body resolve to create the CFG.
Checking the CFG for proper initialization is separated into a following
change to ease code review.

KT-56683

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirFile.kt

@@ -13,6 +13,7 @@ import org.jetbrains.kotlin.fir.FirFileAnnotationsContainer
 import org.jetbrains.kotlin.fir.FirModuleData
 import org.jetbrains.kotlin.fir.FirPackageDirective
 import org.jetbrains.kotlin.fir.expressions.FirAnnotation
+import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
 import org.jetbrains.kotlin.fir.symbols.impl.FirFileSymbol
 import org.jetbrains.kotlin.fir.visitors.*
 import org.jetbrains.kotlin.fir.declarations.ResolveStateAccess
@@ -22,12 +23,13 @@ import org.jetbrains.kotlin.fir.declarations.ResolveStateAccess
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirFile : FirDeclaration() {
+abstract class FirFile : FirDeclaration(), FirControlFlowGraphOwner {
     abstract override val source: KtSourceElement?
     abstract override val annotations: List<FirAnnotation>
     abstract override val moduleData: FirModuleData
     abstract override val origin: FirDeclarationOrigin
     abstract override val attributes: FirDeclarationAttributes
+    abstract override val controlFlowGraphReference: FirControlFlowGraphReference?
     abstract val annotationsContainer: FirFileAnnotationsContainer?
     abstract val packageDirective: FirPackageDirective
     abstract val imports: List<FirImport>
@@ -45,6 +47,8 @@ abstract class FirFile : FirDeclaration() {
 
     abstract override fun replaceAnnotations(newAnnotations: List<FirAnnotation>)
 
+    abstract override fun replaceControlFlowGraphReference(newControlFlowGraphReference: FirControlFlowGraphReference?)
+
     abstract override fun <D> transformAnnotations(transformer: FirTransformer<D>, data: D): FirFile
 
     abstract fun <D> transformAnnotationsContainer(transformer: FirTransformer<D>, data: D): FirFile

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirFileBuilder.kt

@@ -28,6 +28,7 @@ import org.jetbrains.kotlin.fir.declarations.ResolveStateAccess
 import org.jetbrains.kotlin.fir.declarations.asResolveState
 import org.jetbrains.kotlin.fir.declarations.impl.FirFileImpl
 import org.jetbrains.kotlin.fir.expressions.FirAnnotation
+import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
 import org.jetbrains.kotlin.fir.symbols.impl.FirFileSymbol
 import org.jetbrains.kotlin.fir.visitors.*
 

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirFileImpl.kt

@@ -22,6 +22,7 @@ import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirResolveState
 import org.jetbrains.kotlin.fir.declarations.asResolveState
 import org.jetbrains.kotlin.fir.expressions.FirAnnotation
+import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
 import org.jetbrains.kotlin.fir.symbols.impl.FirFileSymbol
 import org.jetbrains.kotlin.fir.visitors.*
 import org.jetbrains.kotlin.fir.MutableOrEmptyList
@@ -49,6 +50,7 @@ internal class FirFileImpl(
     override val symbol: FirFileSymbol,
 ) : FirFile() {
     override val annotations: List<FirAnnotation> get() = annotationsContainer?.annotations ?: emptyList()
+    override var controlFlowGraphReference: FirControlFlowGraphReference? = null
 
     init {
         symbol.bind(this)
@@ -57,6 +59,7 @@ internal class FirFileImpl(
     }
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
+        controlFlowGraphReference?.accept(visitor, data)
         annotationsContainer?.accept(visitor, data)
         packageDirective.accept(visitor, data)
         imports.forEach { it.accept(visitor, data) }
@@ -64,6 +67,7 @@ internal class FirFileImpl(
     }
 
     override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirFileImpl {
+        controlFlowGraphReference = controlFlowGraphReference?.transform(transformer, data)
         transformAnnotationsContainer(transformer, data)
         packageDirective = packageDirective.transform(transformer, data)
         transformImports(transformer, data)
@@ -91,4 +95,8 @@ internal class FirFileImpl(
     }
 
     override fun replaceAnnotations(newAnnotations: List<FirAnnotation>) {}
+
+    override fun replaceControlFlowGraphReference(newControlFlowGraphReference: FirControlFlowGraphReference?) {
+        controlFlowGraphReference = newControlFlowGraphReference
+    }
 }

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/visitors/FirDefaultVisitor.kt

@@ -192,8 +192,6 @@ abstract class FirDefaultVisitor<out R, in D> : FirVisitor<R, D>() {
 
     override fun visitRegularClass(regularClass: FirRegularClass, data: D): R  = visitClass(regularClass, data)
 
-    override fun visitFile(file: FirFile, data: D): R  = visitDeclaration(file, data)
-
     override fun visitScript(script: FirScript, data: D): R  = visitDeclaration(script, data)
 
     override fun visitCodeFragment(codeFragment: FirCodeFragment, data: D): R  = visitDeclaration(codeFragment, data)

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/visitors/FirDefaultVisitorVoid.kt

@@ -192,8 +192,6 @@ abstract class FirDefaultVisitorVoid : FirVisitorVoid() {
 
     override fun visitRegularClass(regularClass: FirRegularClass)  = visitClass(regularClass)
 
-    override fun visitFile(file: FirFile)  = visitDeclaration(file)
-
     override fun visitScript(script: FirScript)  = visitDeclaration(script)
 
     override fun visitCodeFragment(codeFragment: FirCodeFragment)  = visitDeclaration(codeFragment)