[FIR2IR] Set proper offsets for generated data class members

^KT-64435 Fixed

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/ConversionUtils.kt

@@ -78,6 +78,10 @@ fun AbstractKtSourceElement?.startOffsetSkippingComments(): Int? {
     }
 }
 
+internal inline fun <T : IrElement> FirElement.convertWithOffsets(defaultOffset: Int, f: (startOffset: Int, endOffset: Int) -> T): T {
+    return source.convertWithOffsets(defaultOffset, f)
+}
+
 internal inline fun <T : IrElement> FirElement.convertWithOffsets(f: (startOffset: Int, endOffset: Int) -> T): T {
     return source.convertWithOffsets(f)
 }
@@ -89,15 +93,19 @@ internal fun <T : IrElement> FirPropertyAccessor?.convertWithOffsets(
 }
 
 internal inline fun <T : IrElement> KtSourceElement?.convertWithOffsets(f: (startOffset: Int, endOffset: Int) -> T): T {
+    return convertWithOffsets(UNDEFINED_OFFSET, f)
+}
+
+internal inline fun <T : IrElement> KtSourceElement?.convertWithOffsets(defaultOffset: Int, f: (startOffset: Int, endOffset: Int) -> T): T {
     val startOffset: Int
     val endOffset: Int
 
     if (isCompiledElement(psi) || this?.kind == KtFakeSourceElementKind.DataClassGeneratedMembers) {
-        startOffset = UNDEFINED_OFFSET
-        endOffset = UNDEFINED_OFFSET
+        startOffset = defaultOffset
+        endOffset = defaultOffset
     } else {
-        startOffset = this?.startOffsetSkippingComments() ?: this?.startOffset ?: UNDEFINED_OFFSET
-        endOffset = this?.endOffset ?: UNDEFINED_OFFSET
+        startOffset = this?.startOffsetSkippingComments() ?: this?.startOffset ?: defaultOffset
+        endOffset = this?.endOffset ?: defaultOffset
     }
 
     return f(startOffset, endOffset)

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/generators/DataClassMembersGenerator.kt

@@ -21,7 +21,6 @@ import org.jetbrains.kotlin.fir.scopes.getProperties
 import org.jetbrains.kotlin.fir.symbols.impl.FirNamedFunctionSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirPropertySymbol
 import org.jetbrains.kotlin.fir.types.*
-import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.IrGeneratorContextBase
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.IrMemberAccessExpression
@@ -193,8 +192,8 @@ class DataClassMembersGenerator(val components: Fir2IrComponents) : Fir2IrCompon
             irFunction.declareThisReceiverParameter(
                 irClass.defaultType,
                 IrDeclarationOrigin.DEFINED,
-                UNDEFINED_OFFSET,
-                UNDEFINED_OFFSET
+                SYNTHETIC_OFFSET,
+                SYNTHETIC_OFFSET
             )
 
         fun generateHeaders(): List<FirDeclaration> {
@@ -313,8 +312,8 @@ class DataClassMembersGenerator(val components: Fir2IrComponents) : Fir2IrCompon
             val signature = if (klass.symbol.classId.isLocal) null else components.signatureComposer.composeSignature(syntheticCounterpart)
             val symbol = components.declarationStorage.createFunctionSymbol(signature)
             return components.irFactory.createSimpleFunction(
-                startOffset = UNDEFINED_OFFSET,
-                endOffset = UNDEFINED_OFFSET,
+                startOffset = SYNTHETIC_OFFSET,
+                endOffset = SYNTHETIC_OFFSET,
                 origin = origin,
                 name = name,
                 visibility = DescriptorVisibilities.PUBLIC,
@@ -351,8 +350,8 @@ class DataClassMembersGenerator(val components: Fir2IrComponents) : Fir2IrCompon
 
         private fun createSyntheticIrParameter(irFunction: IrFunction, name: Name, type: IrType, index: Int = 0): IrValueParameter =
             components.irFactory.createValueParameter(
-                startOffset = UNDEFINED_OFFSET,
-                endOffset = UNDEFINED_OFFSET,
+                startOffset = SYNTHETIC_OFFSET,
+                endOffset = SYNTHETIC_OFFSET,
                 origin = IrDeclarationOrigin.DEFINED,
                 name = name,
                 type = type,

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/generators/Fir2IrCallableDeclarationsGenerator.kt

@@ -111,11 +111,16 @@ class Fir2IrCallableDeclarationsGenerator(val components: Fir2IrComponents) : Fi
             @Suppress("USELESS_CAST") // K2 warning suppression, TODO: KT-62472
             if (isLambda) ((function as FirAnonymousFunction).typeRef as? FirResolvedTypeRef)?.type?.isSuspendOrKSuspendFunctionType(session) == true
             else function.isSuspend
-        val created = function.convertWithOffsets { startOffset, endOffset ->
+        val defaultOffset = when {
+            function.origin == FirDeclarationOrigin.Synthetic.DataClassMember -> SYNTHETIC_OFFSET
+            updatedOrigin == IrDeclarationOrigin.DELEGATED_MEMBER -> SYNTHETIC_OFFSET
+            else -> UNDEFINED_OFFSET
+        }
+        val created = function.convertWithOffsets(defaultOffset) { startOffset, endOffset ->
             classifierStorage.preCacheTypeParameters(function, symbol)
             irFactory.createSimpleFunction(
-                startOffset = if (updatedOrigin == IrDeclarationOrigin.DELEGATED_MEMBER) SYNTHETIC_OFFSET else startOffset,
-                endOffset = if (updatedOrigin == IrDeclarationOrigin.DELEGATED_MEMBER) SYNTHETIC_OFFSET else endOffset,
+                startOffset = startOffset,
+                endOffset = endOffset,
                 origin = updatedOrigin,
                 name = name,
                 visibility = components.visibilityConverter.convertToDescriptorVisibility(visibility),