diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/common/ir/Ir.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/common/ir/Ir.kt
index 7586a8568ca..9b4c52116d8 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/common/ir/Ir.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/common/ir/Ir.kt
@@ -14,7 +14,6 @@ import org.jetbrains.kotlin.ir.util.SymbolTable
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.types.KotlinType
-import org.jetbrains.kotlin.types.SimpleType
 import org.jetbrains.kotlin.util.OperatorNameConventions
 
 // This is what Context collects about IR.
diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanLower.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanLower.kt
index 38263f69d48..4be73f8d7eb 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanLower.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanLower.kt
@@ -40,6 +40,10 @@ internal class KonanLower(val context: Context) {
     fun lowerModule(irModule: IrModuleFragment) {
         val phaser = PhaseManager(context)
 
+        phaser.phase(KonanPhase.LOWER_SPECIAL_CALLS) {
+            irModule.files.forEach(SpecialCallsLowering(context)::lower)
+        }
+
         phaser.phase(KonanPhase.LOWER_INLINE_CONSTRUCTORS) {
             InlineConstructorsTransformation(context).lower(irModule)
         }
diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanPhases.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanPhases.kt
index 04b3a539c17..e2f7d2a49e3 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanPhases.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanPhases.kt
@@ -28,8 +28,9 @@ enum class KonanPhase(val description: String,
     /* */ SERIALIZER("Serialize descriptor tree and inline IR bodies"),
     /* */ BACKEND("All backend"),
     /* ... */ LOWER("IR Lowering"),
-    /* ... ... */ LOWER_INLINE_CONSTRUCTORS("Inline constructors transformation"),
-    /* ... ... */ LOWER_INLINE("Functions inlining", LOWER_INLINE_CONSTRUCTORS),
+    /* ... ... */ LOWER_SPECIAL_CALLS("Special calls processing before inlining"),
+    /* ... ... */ LOWER_INLINE_CONSTRUCTORS("Inline constructors transformation", LOWER_SPECIAL_CALLS),
+    /* ... ... */ LOWER_INLINE("Functions inlining", LOWER_INLINE_CONSTRUCTORS, LOWER_SPECIAL_CALLS),
     /* ... ... ...  */ DESERIALIZER("Deserialize inline bodies"),
     /* ... ... */ LOWER_INTEROP_PART1("Interop lowering, part 1", LOWER_INLINE),
     /* ... ... */ LOWER_FOR_LOOPS("For loops lowering"),
diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/BuiltinOperatorLowering.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/BuiltinOperatorLowering.kt
index 61dac26a686..f489b86adf8 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/BuiltinOperatorLowering.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/BuiltinOperatorLowering.kt
@@ -19,23 +19,20 @@ package org.jetbrains.kotlin.backend.konan.lower
 import org.jetbrains.kotlin.backend.common.BodyLoweringPass
 import org.jetbrains.kotlin.backend.common.atMostOne
 import org.jetbrains.kotlin.backend.konan.Context
-import org.jetbrains.kotlin.backend.konan.KonanConfigKeys.Companion.ENABLE_ASSERTIONS
-import org.jetbrains.kotlin.backend.konan.isStdlib
 import org.jetbrains.kotlin.backend.konan.isValueType
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltinOperatorDescriptor
-import org.jetbrains.kotlin.ir.expressions.*
+import org.jetbrains.kotlin.ir.expressions.IrBody
+import org.jetbrains.kotlin.ir.expressions.IrCall
+import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.expressions.IrTypeOperatorCall
 import org.jetbrains.kotlin.ir.expressions.impl.IrCallImpl
-import org.jetbrains.kotlin.ir.expressions.impl.IrCompositeImpl
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.ir.util.isNullConst
 import org.jetbrains.kotlin.ir.util.type
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
-import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
-import org.jetbrains.kotlin.resolve.descriptorUtil.module
 import org.jetbrains.kotlin.types.typeUtil.isNothing
 import org.jetbrains.kotlin.types.typeUtil.isSubtypeOf
-import org.jetbrains.kotlin.types.typeUtil.isUnit
 
 /**
  * This lowering pass lowers some calls to [IrBuiltinOperatorDescriptor]s.
@@ -54,20 +51,11 @@ private class BuiltinOperatorTransformer(val context: Context) : IrElementTransf
 
     private val builtIns = context.builtIns
     private val irBuiltins = context.irModule!!.irBuiltins
-    private val enableAssertions = context.config.configuration.getBoolean(ENABLE_ASSERTIONS)
-
-    private val assertSymbols = context.ir.symbols.asserts
 
     override fun visitCall(expression: IrCall): IrExpression {
         expression.transformChildrenVoid(this)
         val descriptor = expression.descriptor
 
-        // Replace assert() call with an empty composite if assertions are not enabled.
-        if (!enableAssertions && expression.symbol in assertSymbols) {
-            assert(expression.type.isUnit())
-            return IrCompositeImpl(expression.startOffset, expression.endOffset, expression.type)
-        }
-
         if (descriptor is IrBuiltinOperatorDescriptor) {
             return transformBuiltinOperator(expression)
         }
diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/SpecialCallsLowering.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/SpecialCallsLowering.kt
new file mode 100644
index 00000000000..65aa7f87241
--- /dev/null
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/SpecialCallsLowering.kt
@@ -0,0 +1,39 @@
+package org.jetbrains.kotlin.backend.konan.lower
+
+import org.jetbrains.kotlin.backend.common.FileLoweringPass
+import org.jetbrains.kotlin.backend.konan.Context
+import org.jetbrains.kotlin.backend.konan.KonanConfigKeys
+import org.jetbrains.kotlin.ir.declarations.IrFile
+import org.jetbrains.kotlin.ir.expressions.IrCall
+import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.expressions.impl.IrCompositeImpl
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
+import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
+import org.jetbrains.kotlin.types.typeUtil.isUnit
+
+/**
+ * This pass runs before inlining and performs the following additional transformations over some calls:
+ *     - Assertion call removal.
+ */
+internal class SpecialCallsLowering(val context: Context) : FileLoweringPass {
+
+    private val asserts = context.ir.symbols.asserts
+    private val enableAssertions = context.config.configuration.getBoolean(KonanConfigKeys.ENABLE_ASSERTIONS)
+
+    override fun lower(irFile: IrFile) {
+        irFile.transformChildrenVoid(object : IrElementTransformerVoid() {
+
+            override fun visitCall(expression: IrCall): IrExpression {
+                expression.transformChildrenVoid(this)
+
+                // Replace assert() call with an empty composite if assertions are not enabled.
+                if (!enableAssertions && expression.symbol in asserts) {
+                    assert(expression.type.isUnit())
+                    return IrCompositeImpl(expression.startOffset, expression.endOffset, expression.type)
+                }
+
+                return expression
+            }
+        })
+    }
+}
\ No newline at end of file