[IR] Add REINTERPRET_CAST operator in IrTypeOperatorCall

- fix BE
 - fix Serializer
 - implement builder
 - make Ir a bit more type-correct
 - support developer mode (lowering [dynamic]implicit cast meterialized as general cast)
 - fix autoboxing lowering

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/builders/ExpressionHelpers.kt

@@ -314,6 +314,9 @@ fun IrBuilderWithScope.irAs(argument: IrExpression, type: IrType) =
 fun IrBuilderWithScope.irImplicitCast(argument: IrExpression, type: IrType) =
     IrTypeOperatorCallImpl(startOffset, endOffset, type, IrTypeOperator.IMPLICIT_CAST, type, argument)
 
+fun IrBuilderWithScope.irReinterpretCast(argument: IrExpression, type: IrType) =
+    IrTypeOperatorCallImpl(startOffset, endOffset, type, IrTypeOperator.REINTERPRET_CAST, type, argument)
+
 fun IrBuilderWithScope.irInt(value: Int) =
     IrConstImpl.int(startOffset, endOffset, context.irBuiltIns.intType, value)
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/IrTypeOperatorCall.kt

@@ -49,7 +49,11 @@ enum class IrTypeOperator {
      * Implicit dynamic cast: implicit cast from `dynamic` to `T`.
      * This currently can happen in Kotlin/JS only.
      */
-    IMPLICIT_DYNAMIC_CAST;
+    IMPLICIT_DYNAMIC_CAST,
+    /**
+     * C-like reinterpret_cast<T> using as primitive type operation in JS
+     */
+    REINTERPRET_CAST;
 }
 
 interface IrTypeOperatorCall : IrExpression {