diff --git a/clang-tools-extra/clangd/SourceCode.h b/clang-tools-extra/clangd/SourceCode.h
--- a/clang-tools-extra/clangd/SourceCode.h
+++ b/clang-tools-extra/clangd/SourceCode.h
@@ -232,6 +232,11 @@
 llvm::StringMap<unsigned> collectIdentifiers(llvm::StringRef Content,
                                              const format::FormatStyle &Style);
 
+/// Collects all ranges of the given identifier in the source code.
+std::vector<Range> collectIdentifierRanges(llvm::StringRef Identifier,
+                                           llvm::StringRef Content,
+                                           const LangOptions &LangOpts);
+
 /// Collects words from the source code.
 /// Unlike collectIdentifiers:
 /// - also finds text in comments:
diff --git a/clang-tools-extra/clangd/SourceCode.cpp b/clang-tools-extra/clangd/SourceCode.cpp
--- a/clang-tools-extra/clangd/SourceCode.cpp
+++ b/clang-tools-extra/clangd/SourceCode.cpp
@@ -719,41 +719,53 @@
   return formatReplacements(Code, std::move(*CleanReplaces), Style);
 }
 
-void lex(llvm::StringRef Code, const format::FormatStyle &Style,
-         llvm::function_ref<void(const clang::Token &, Position)> Action) {
+void lex(llvm::StringRef Code, const LangOptions &LangOpts,
+         llvm::function_ref<void(const clang::Token &, const SourceManager &SM)>
+             Action) {
   // FIXME: InMemoryFileAdapter crashes unless the buffer is null terminated!
   std::string NullTerminatedCode = Code.str();
   SourceManagerForFile FileSM("dummy.cpp", NullTerminatedCode);
   auto &SM = FileSM.get();
   auto FID = SM.getMainFileID();
-  Lexer Lex(FID, SM.getBuffer(FID), SM, format::getFormattingLangOpts(Style));
+  // Create a raw lexer (with no associated preprocessor object).
+  Lexer Lex(FID, SM.getBuffer(FID), SM, LangOpts);
   Token Tok;
 
   while (!Lex.LexFromRawLexer(Tok))
-    Action(Tok, sourceLocToPosition(SM, Tok.getLocation()));
+    Action(Tok, SM);
   // LexFromRawLexer returns true after it lexes last token, so we still have
   // one more token to report.
-  Action(Tok, sourceLocToPosition(SM, Tok.getLocation()));
+  Action(Tok, SM);
 }
 
 llvm::StringMap<unsigned> collectIdentifiers(llvm::StringRef Content,
                                              const format::FormatStyle &Style) {
   llvm::StringMap<unsigned> Identifiers;
-  lex(Content, Style, [&](const clang::Token &Tok, Position) {
-    switch (Tok.getKind()) {
-    case tok::identifier:
-      ++Identifiers[Tok.getIdentifierInfo()->getName()];
-      break;
-    case tok::raw_identifier:
+  auto LangOpt = format::getFormattingLangOpts(Style);
+  lex(Content, LangOpt, [&](const clang::Token &Tok, const SourceManager &) {
+    if (Tok.getKind() == tok::raw_identifier)
       ++Identifiers[Tok.getRawIdentifier()];
-      break;
-    default:
-      break;
-    }
   });
   return Identifiers;
 }
 
+std::vector<Range> collectIdentifierRanges(llvm::StringRef Identifier,
+                                           llvm::StringRef Content,
+                                           const LangOptions &LangOpts) {
+  std::vector<Range> Ranges;
+  lex(Content, LangOpts, [&](const clang::Token &Tok, const SourceManager &SM) {
+    if (Tok.getKind() != tok::raw_identifier)
+      return;
+    if (Tok.getRawIdentifier() != Identifier)
+      return;
+    auto Range = getTokenRange(SM, LangOpts, Tok.getLocation());
+    if (!Range)
+      return;
+    Ranges.push_back(*Range);
+  });
+  return Ranges;
+}
+
 namespace {
 struct NamespaceEvent {
   enum {
@@ -786,8 +798,9 @@
   std::string NSName;
 
   NamespaceEvent Event;
-  lex(Code, Style, [&](const clang::Token &Tok, Position P) {
-    Event.Pos = std::move(P);
+  lex(Code, format::getFormattingLangOpts(Style),
+      [&](const clang::Token &Tok,const SourceManager &SM) {
+    Event.Pos = sourceLocToPosition(SM, Tok.getLocation());
     switch (Tok.getKind()) {
     case tok::raw_identifier:
       // In raw mode, this could be a keyword or a name.
diff --git a/clang-tools-extra/clangd/unittests/SourceCodeTests.cpp b/clang-tools-extra/clangd/unittests/SourceCodeTests.cpp
--- a/clang-tools-extra/clangd/unittests/SourceCodeTests.cpp
+++ b/clang-tools-extra/clangd/unittests/SourceCodeTests.cpp
@@ -680,6 +680,27 @@
     EXPECT_EQ(Res.EnclosingNamespace, Case.EnclosingNamespace) << Test.code();
   }
 }
+
+TEST(SourceCodeTests, IdentifierRanges) {
+  Annotations Code(R"cpp(
+   class [[Foo]] {};
+   // Foo
+   /* Foo */
+   void f([[Foo]]* foo1) {
+     [[Foo]] foo2;
+     auto S = [[Foo]]();
+// cross-line identifier is not supported.
+F\
+o\
+o foo2;
+   }
+  )cpp");
+  LangOptions LangOpts;
+  LangOpts.CPlusPlus = true;
+  EXPECT_EQ(Code.ranges(),
+            collectIdentifierRanges("Foo", Code.code(), LangOpts));
+}
+
 } // namespace
 } // namespace clangd
 } // namespace clang