diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/CompareTo.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/CompareTo.kt
index a8b2b9d3d24..9edc646b5f6 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/CompareTo.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/CompareTo.kt
@@ -25,27 +25,19 @@ import org.jetbrains.org.objectweb.asm.commons.InstructionAdapter
 public class CompareTo : IntrinsicMethod() {
 
     private fun genInvoke(type: Type?, v: InstructionAdapter) {
-        if (type == Type.INT_TYPE) {
-            v.invokestatic(IntrinsicMethods.INTRINSICS_CLASS_NAME, "compare", "(II)I", false)
-        }
-        else if (type == Type.LONG_TYPE) {
-            v.invokestatic(IntrinsicMethods.INTRINSICS_CLASS_NAME, "compare", "(JJ)I", false)
-        }
-        else if (type == Type.FLOAT_TYPE) {
-            v.invokestatic("java/lang/Float", "compare", "(FF)I", false)
-        }
-        else if (type == Type.DOUBLE_TYPE) {
-            v.invokestatic("java/lang/Double", "compare", "(DD)I", false)
-        }
-        else {
-            throw UnsupportedOperationException()
+        when (type) {
+            Type.INT_TYPE -> v.invokestatic(IntrinsicMethods.INTRINSICS_CLASS_NAME, "compare", "(II)I", false)
+            Type.LONG_TYPE -> v.invokestatic(IntrinsicMethods.INTRINSICS_CLASS_NAME, "compare", "(JJ)I", false)
+            Type.FLOAT_TYPE -> v.invokestatic("java/lang/Float", "compare", "(FF)I", false)
+            Type.DOUBLE_TYPE -> v.invokestatic("java/lang/Double", "compare", "(DD)I", false)
+            else -> throw UnsupportedOperationException()
         }
     }
 
     override fun toCallable(method: CallableMethod): Callable {
-        val argumentType = comparisonOperandType(method.thisType ?: method.receiverType, method.argumentTypes.first())
-        return binaryIntrinsic(method.returnType, argumentType, argumentType, null) {
-            genInvoke(argumentType, it)
+        val parameterType = comparisonOperandType(method.thisType ?: method.receiverType, method.parameterTypes.single())
+        return binaryIntrinsic(method.returnType, parameterType, parameterType, null) {
+            genInvoke(parameterType, it)
         }
     }
 }
diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/IteratorNext.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/IteratorNext.kt
index c2e0347233a..71410346347 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/IteratorNext.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/IteratorNext.kt
@@ -30,36 +30,18 @@ import org.jetbrains.org.objectweb.asm.commons.InstructionAdapter
 
 public class IteratorNext : IntrinsicMethod() {
 
-    protected fun getIteratorName(returnType: Type): String {
-        val name: String
-        if (returnType == Type.CHAR_TYPE) {
-            name = "Char"
+    private fun getIteratorName(returnType: Type): String {
+        return when (returnType) {
+            Type.CHAR_TYPE -> "Char"
+            Type.BOOLEAN_TYPE -> "Boolean"
+            Type.BYTE_TYPE -> "Byte"
+            Type.SHORT_TYPE -> "Short"
+            Type.INT_TYPE -> "Int"
+            Type.LONG_TYPE -> "Long"
+            Type.FLOAT_TYPE -> "Float"
+            Type.DOUBLE_TYPE -> "Double"
+            else -> throw UnsupportedOperationException("Can't get correct name for iterator from type: " + returnType)
         }
-        else if (returnType == Type.BOOLEAN_TYPE) {
-            name = "Boolean"
-        }
-        else if (returnType == Type.BYTE_TYPE) {
-            name = "Byte"
-        }
-        else if (returnType == Type.SHORT_TYPE) {
-            name = "Short"
-        }
-        else if (returnType == Type.INT_TYPE) {
-            name = "Int"
-        }
-        else if (returnType == Type.LONG_TYPE) {
-            name = "Long"
-        }
-        else if (returnType == Type.FLOAT_TYPE) {
-            name = "Float"
-        }
-        else if (returnType == Type.DOUBLE_TYPE) {
-            name = "Double"
-        }
-        else {
-            throw UnsupportedOperationException("Can't get correct name for iterator from type: " + returnType)
-        }
-        return name
     }
 
 
diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/RangeTo.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/RangeTo.kt
index 776e5b5fdd7..1ab1a0058c7 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/RangeTo.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/intrinsics/RangeTo.kt
@@ -17,6 +17,7 @@
 package org.jetbrains.kotlin.codegen.intrinsics
 
 import org.jetbrains.kotlin.codegen.Callable
+import org.jetbrains.kotlin.codegen.CallableMethod
 import org.jetbrains.kotlin.codegen.ExpressionCodegen
 import org.jetbrains.kotlin.codegen.StackValue
 import org.jetbrains.kotlin.descriptors.FunctionDescriptor
@@ -40,8 +41,7 @@ public class RangeTo : IntrinsicMethod() {
         }
     }
 
-    override fun toCallable(fd: FunctionDescriptor, isSuper: Boolean, resolvedCall: ResolvedCall<*>, codegen: ExpressionCodegen): Callable {
-        val method = codegen.getState().getTypeMapper().mapToCallableMethod(fd, false, codegen.getContext())
+    override fun toCallable(method: CallableMethod): Callable {
         val argType = nameToPrimitive(method.returnType.getInternalName().substringAfter("kotlin/").substringBefore("Range"))
         return object : IntrinsicCallable(method.returnType, method.valueParameterTypes.map { argType }, nullOr(method.thisType, argType), nullOr(method.receiverType, argType)) {
             override fun beforeParameterGeneration(v: InstructionAdapter, value: StackValue?) {