Index: clang/tools/libclang/CIndex.cpp
===================================================================
--- clang/tools/libclang/CIndex.cpp
+++ clang/tools/libclang/CIndex.cpp
@@ -164,6 +164,50 @@
   return Result;
 }
 
+static void clang_tokenize_impl(ASTUnit *CXXUnit, SourceRange R,
+                                CXToken **Tokens, unsigned *NumTokens);
+
+SourceRange cxloc::translateCharRangeToTokenRange(CXTranslationUnit TU,
+                                                  CXSourceRange R) {
+  if (isNotUsableTU(TU)) {
+    LOG_BAD_TU(TU);
+    return {};
+  }
+
+  ASTUnit *CXXUnit = cxtu::getASTUnit(TU);
+  if (!CXXUnit)
+    return {};
+
+  CXToken *Tokens;
+  unsigned int NumTokens;
+  clang_tokenize_impl(
+      CXXUnit,
+      // FIXME: naturally tokenization doesn't expect a token range - we should
+      // use a distinct type.
+      SourceRange(SourceLocation::getFromRawEncoding(R.begin_int_data),
+                  SourceLocation::getFromRawEncoding(R.end_int_data)),
+      &Tokens, &NumTokens);
+
+  if (NumTokens == 0)
+    return {};
+
+  // Check that then begin of the range actually points to begin of some token.
+  const CXSourceRange FirstTokenRng = clang_getTokenExtent(TU, Tokens[0]);
+  if (FirstTokenRng.begin_int_data != R.begin_int_data)
+    return {};
+
+  const CXSourceRange LastTokenRng =
+      clang_getTokenExtent(TU, Tokens[NumTokens - 1]);
+  const SourceLocation LastTokenBegin =
+      SourceLocation::getFromRawEncoding(LastTokenRng.begin_int_data);
+
+  if (!LastTokenBegin.isValid())
+    return {};
+
+  return SourceRange(SourceLocation::getFromRawEncoding(R.begin_int_data),
+                     LastTokenBegin);
+}
+
 //===----------------------------------------------------------------------===//
 // Cursor visitor.
 //===----------------------------------------------------------------------===//
@@ -6908,6 +6952,23 @@
   return Token;
 }
 
+static void clang_tokenize_impl(ASTUnit *CXXUnit, SourceRange R,
+                                CXToken **Tokens, unsigned *NumTokens) {
+  if (!CXXUnit || !Tokens || !NumTokens)
+    return;
+
+  SmallVector<CXToken, 32> CXTokens;
+  getTokens(CXXUnit, R, CXTokens);
+
+  if (CXTokens.empty())
+    return;
+
+  *Tokens = static_cast<CXToken *>(
+      llvm::safe_malloc(sizeof(CXToken) * CXTokens.size()));
+  memmove(*Tokens, CXTokens.data(), sizeof(CXToken) * CXTokens.size());
+  *NumTokens = CXTokens.size();
+}
+
 void clang_tokenize(CXTranslationUnit TU, CXSourceRange Range, CXToken **Tokens,
                     unsigned *NumTokens) {
   LOG_FUNC_SECTION { *Log << TU << ' ' << Range; }
@@ -6932,16 +6993,7 @@
   if (R.isInvalid())
     return;
 
-  SmallVector<CXToken, 32> CXTokens;
-  getTokens(CXXUnit, R, CXTokens);
-
-  if (CXTokens.empty())
-    return;
-
-  *Tokens = static_cast<CXToken *>(
-      llvm::safe_malloc(sizeof(CXToken) * CXTokens.size()));
-  memmove(*Tokens, CXTokens.data(), sizeof(CXToken) * CXTokens.size());
-  *NumTokens = CXTokens.size();
+  clang_tokenize_impl(CXXUnit, R, Tokens, NumTokens);
 }
 
 void clang_disposeTokens(CXTranslationUnit TU, CXToken *Tokens,
Index: clang/tools/libclang/CXSourceLocation.h
===================================================================
--- clang/tools/libclang/CXSourceLocation.h
+++ clang/tools/libclang/CXSourceLocation.h
@@ -71,7 +71,12 @@
                      SourceLocation::getFromRawEncoding(R.end_int_data));
 }
 
-
+/// Translates CXSourceRange to SourceRange.
+/// The semantics of \p R are:
+/// R.begin_int_data is begin of the first token of the range.
+/// R.end_int_data is begin of the last token of the range.
+SourceRange translateCharRangeToTokenRange(CXTranslationUnit TU,
+                                           CXSourceRange R);
 }} // end namespace: clang::cxloc
 
 #endif