diff --git a/runtime/src/main/cpp/KString.cpp b/runtime/src/main/cpp/KString.cpp
index c58f7027c84..61fc6134170 100644
--- a/runtime/src/main/cpp/KString.cpp
+++ b/runtime/src/main/cpp/KString.cpp
@@ -47,46 +47,6 @@ OBJ_GETTER(utf8ToUtf16, const char* rawString, size_t rawStringLength) {
   RETURN_OBJ(result->obj());
 }
 
-void checkParsingErrors(const char* c_str, char* end, std::string::size_type c_str_size) {
-  if (end == c_str) {
-    ThrowNumberFormatException();
-  }
-  // According to http://docs.oracle.com/javase/8/docs/api/java/lang/Double.html#valueOf-java.lang.String-
-  // trailing whitespace characters must be ignored so we need to do an additional check.
-  for (char* p = end; p < c_str + c_str_size; p++) {
-    if (!isspace(*p)) {
-      ThrowNumberFormatException();
-    }
-  }
-}
-
-// TODO: Java Double.valueOf specification requires mandatory binary exponent character (p) in the string parsed if the string is a hex one.
-// See: http://docs.oracle.com/javase/8/docs/api/java/lang/Double.html#valueOf-java.lang.String-
-// E.g.
-// "0x77p0".toDouble() // OK for both Kotlin/JVM and Kotlin/Native.
-// "0x77".toDouble()   // throws NumberFormatException in Kotlin/JVM and OK in Kotlin/Native.
-// Do we need to handle such case? Or it is OK to consume such strings?
-KFloat parseFloat(KString value) {
-  const KChar* utf16 = CharArrayAddressOfElementAt(value, 0);
-  std::string utf8;
-  utf8::utf16to8(utf16, utf16 + value->count_, back_inserter(utf8));
-  char* end = nullptr;
-  KFloat result = strtof(utf8.c_str(), &end);
-  checkParsingErrors(utf8.c_str(), end, utf8.size());
-  return result;
-}
-
-KDouble parseDouble(KString value) {
-  const KChar* utf16 =
-      CharArrayAddressOfElementAt(value, 0);
-  std::string utf8;
-  utf8::utf16to8(utf16, utf16 + value->count_, back_inserter(utf8));
-  char* end = nullptr;
-  KDouble result = strtod(utf8.c_str(), &end);
-  checkParsingErrors(utf8.c_str(), end, utf8.size());
-  return result;
-}
-
 // Case conversion is derived work from Apache Harmony.
 // Unicode 3.0.1 (same as Unicode 3.0.0)
 enum CharacterClass {
@@ -731,6 +691,46 @@ int iswlower_Konan(KChar ch) {
   return getType(ch) == LOWERCASE_LETTER;
 }
 
+void checkParsingErrors(const char* c_str, char* end, std::string::size_type c_str_size) {
+  if (end == c_str) {
+    ThrowNumberFormatException();
+  }
+  // According to http://docs.oracle.com/javase/8/docs/api/java/lang/Double.html#valueOf-java.lang.String-
+  // trailing whitespace characters must be ignored so we need to do an additional check.
+  for (char* p = end; p < c_str + c_str_size; p++) {
+    if (!iswspace_Konan(*p)) {
+      ThrowNumberFormatException();
+    }
+  }
+}
+
+// TODO: Java Double.valueOf specification requires mandatory binary exponent character (p) in the string parsed if the string is a hex one.
+// See: http://docs.oracle.com/javase/8/docs/api/java/lang/Double.html#valueOf-java.lang.String-
+// E.g.
+// "0x77p0".toDouble() // OK for both Kotlin/JVM and Kotlin/Native.
+// "0x77".toDouble()   // throws NumberFormatException in Kotlin/JVM and OK in Kotlin/Native.
+// Do we need to handle such case? Or it is OK to consume such strings?
+KFloat parseFloat(KString value) {
+  const KChar* utf16 = CharArrayAddressOfElementAt(value, 0);
+  std::string utf8;
+  utf8::utf16to8(utf16, utf16 + value->count_, back_inserter(utf8));
+  char* end = nullptr;
+  KFloat result = strtof(utf8.c_str(), &end);
+  checkParsingErrors(utf8.c_str(), end, utf8.size());
+  return result;
+}
+
+KDouble parseDouble(KString value) {
+  const KChar* utf16 =
+      CharArrayAddressOfElementAt(value, 0);
+  std::string utf8;
+  utf8::utf16to8(utf16, utf16 + value->count_, back_inserter(utf8));
+  char* end = nullptr;
+  KDouble result = strtod(utf8.c_str(), &end);
+  checkParsingErrors(utf8.c_str(), end, utf8.size());
+  return result;
+}
+
 } // namespace
 
 extern "C" {