CODEGEN: construction body evaluation

for code:
--------8<--------
> cat ../backend.native/tests/codegen/object/initialization.kt
open class A(val a:Int, val b:Int)

open class B(val c:Int, d:Int):A(c, d)

open class C(i:Int, j:Int):B(i + j, 42)

class D (i: Int, j:Int) : C(i, j){
   constructor(i: Int, j:Int, k:Int) : this(i, j) {
      foo(i)
   }
   constructor():this(1, 2)
}

fun foo(i:Int) : Unit {}

fun foo(i:Int, j:Int):Int {
   val c = D(i, j)
   return c.c
}
--------8<--------

folowing code is generated:
--------8<--------
; ModuleID = '../backend.native/tests/codegen/object/initialization.kt.bc'
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.12.0"
...

define i8* @"kfun:C.<init>(Int;Int)"(i8*, i32, i32) {
entry:
  %this = alloca i8*
  store i8* %0, i8** %this
  %i = alloca i32
  store i32 %1, i32* %i
  %j = alloca i32
  store i32 %2, i32* %j
  %tmp_0 = load i8*, i8** %this
  %tmp_3 = load i32, i32* %i
  %tmp_4 = load i32, i32* %j
  %tmp_2 = call i32 @Kotlin_Int_plus_Int(i32 %tmp_3, i32 %tmp_4)
  %tmp_6 = load i8*, i8** %this
  %tmp_1 = call i8* @"kfun:B.<init>(Int;Int)"(i8* %tmp_6, i32 %tmp_2, i32 42)
  ret i8* %tmp_0
}

define i8* @"kfun:D.<init>(Int;Int)"(i8*, i32, i32) {
entry:
  %this = alloca i8*
  store i8* %0, i8** %this
  %i = alloca i32
  store i32 %1, i32* %i
  %j = alloca i32
  store i32 %2, i32* %j
  %tmp_0 = load i8*, i8** %this
  %tmp_2 = load i32, i32* %i
  %tmp_3 = load i32, i32* %j
  %tmp_4 = load i8*, i8** %this
  %tmp_1 = call i8* @"kfun:C.<init>(Int;Int)"(i8* %tmp_4, i32 %tmp_2, i32 %tmp_3)
  ret i8* %tmp_0
}

define i8* @"kfun:D.<init>(Int;Int;Int)"(i8*, i32, i32, i32) {
entry:
  %this = alloca i8*
  store i8* %0, i8** %this
  %i = alloca i32
  store i32 %1, i32* %i
  %j = alloca i32
  store i32 %2, i32* %j
  %k = alloca i32
  store i32 %3, i32* %k
  %tmp_0 = load i8*, i8** %this
  %tmp_2 = load i32, i32* %i
  %tmp_3 = load i32, i32* %j
  %tmp_4 = load i8*, i8** %this
  %tmp_1 = call i8* @"kfun:D.<init>(Int;Int)"(i8* %tmp_4, i32 %tmp_2, i32 %tmp_3)
  %tmp_5 = load i32, i32* %i
  call void @"kfun:foo(Int)"(i32 %tmp_5)
  ret i8* %tmp_0
}

--------8<--------

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/IrToBitcode.kt

@@ -20,6 +20,7 @@ import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
 import org.jetbrains.kotlin.ir.visitors.acceptVoid
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.DescriptorUtils
+import org.jetbrains.kotlin.resolve.descriptorUtil.getAllSuperclassesWithoutAny
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.TypeUtils
 import org.jetbrains.kotlin.types.typeUtil.isNullableNothing
@@ -168,12 +169,23 @@ internal class CodeGeneratorVisitor(val context: Context) : IrElementVisitorVoid
                     val value = codegen.load(variable!!, codegen.newVar())
                     codegen.store(value, fieldPtr!!)
                 }
+        /**
+         * IR for kotlin.Any is:
+         * BLOCK_BODY
+         *   DELEGATING_CONSTRUCTOR_CALL 'constructor Any()'
+         *   INSTANCE_INITIALIZER_CALL classDescriptor='Any'
+         *
+         *   to avoid possible recursion we manually reject body generation for Any.
+         */
+
+        if (!skipConstructorBodyGeneration(declaration))
+            declaration.acceptChildrenVoid(this)
 
-        /* TODO: body */
         codegen.ret(thisPtr)
         logger.log("visitConstructor           : ${ir2string(declaration)}")
     }
 
+
     //-------------------------------------------------------------------------//
 
     override fun visitBlockBody(body: IrBlockBody) {
@@ -866,4 +878,19 @@ internal class CodeGeneratorVisitor(val context: Context) : IrElementVisitorVoid
         return callDirect(descriptor, rargs!!, result)
     }
 
+    //-------------------------------------------------------------------------//
+
+    private fun skipConstructorBodyGeneration(declaration: IrConstructor): Boolean {
+        var  skipBody = false
+        declaration.acceptChildrenVoid(object : IrElementVisitorVoid {
+            override fun visitElement(element: IrElement) {
+                element.acceptChildrenVoid(this)
+            }
+
+            override fun visitDelegatingConstructorCall(expression: IrDelegatingConstructorCall) {
+                skipBody = expression.descriptor == declaration.descriptor
+            }
+        })
+        return skipBody
+    }
 }