diff --git a/clang/include/clang/Tooling/DependencyScanning/DependencyScanningService.h b/clang/include/clang/Tooling/DependencyScanning/DependencyScanningService.h
--- a/clang/include/clang/Tooling/DependencyScanning/DependencyScanningService.h
+++ b/clang/include/clang/Tooling/DependencyScanning/DependencyScanningService.h
@@ -10,6 +10,11 @@
 #define LLVM_CLANG_TOOLING_DEPENDENCY_SCANNING_SERVICE_H
 
 #include "clang/Tooling/DependencyScanning/DependencyScanningFilesystem.h"
+#include "clang/Tooling/ArgumentsAdjusters.h"
+
+#include <map>
+#include <mutex>
+#include <string>
 
 namespace clang {
 namespace tooling {
@@ -42,6 +47,20 @@
   Full,
 };
 
+class ResourceDirectoryCache {
+public:
+  /// findResourceDir finds the resource directory relative to the clang
+  /// compiler being used in Args, by running it with "-print-resource-dir"
+  /// option and cache the results for reuse. \returns resource directory path
+  /// associated with the given invocation command or empty string if the
+  /// compiler path is NOT an absolute path.
+  StringRef findResourceDir(const CommandLineArguments &Args, bool ClangCLMode);
+
+private:
+  std::map<std::string, std::string> Cache;
+  std::mutex CacheLock;
+};
+
 /// The dependency scanning service contains the shared state that is used by
 /// the invidual dependency scanning workers.
 class DependencyScanningService {
diff --git a/clang/lib/Tooling/DependencyScanning/DependencyScanningService.cpp b/clang/lib/Tooling/DependencyScanning/DependencyScanningService.cpp
--- a/clang/lib/Tooling/DependencyScanning/DependencyScanningService.cpp
+++ b/clang/lib/Tooling/DependencyScanning/DependencyScanningService.cpp
@@ -8,11 +8,65 @@
 
 #include "clang/Tooling/DependencyScanning/DependencyScanningService.h"
 #include "llvm/Support/TargetSelect.h"
+#include "llvm/Support/FileUtilities.h"
+#include "llvm/Support/Program.h"
 
 using namespace clang;
 using namespace tooling;
 using namespace dependencies;
 
+StringRef
+ResourceDirectoryCache::findResourceDir(const CommandLineArguments &Args,
+                                        bool ClangCLMode) {
+  if (Args.size() < 1)
+    return "";
+
+  const std::string &ClangBinaryPath = Args[0];
+  if (!llvm::sys::path::is_absolute(ClangBinaryPath))
+    return "";
+
+  const std::string &ClangBinaryName =
+      std::string(llvm::sys::path::filename(ClangBinaryPath));
+
+  std::unique_lock<std::mutex> LockGuard(CacheLock);
+  const auto &CachedResourceDir = Cache.find(ClangBinaryPath);
+  if (CachedResourceDir != Cache.end())
+    return CachedResourceDir->second;
+
+  std::vector<StringRef> PrintResourceDirArgs{ClangBinaryName};
+  if (ClangCLMode)
+    PrintResourceDirArgs.push_back("/clang:-print-resource-dir");
+  else
+    PrintResourceDirArgs.push_back("-print-resource-dir");
+
+  llvm::SmallString<64> OutputFile, ErrorFile;
+  llvm::sys::fs::createTemporaryFile("print-resource-dir-output",
+                                     "" /*no-suffix*/, OutputFile);
+  llvm::sys::fs::createTemporaryFile("print-resource-dir-error",
+                                     "" /*no-suffix*/, ErrorFile);
+  llvm::FileRemover OutputRemover(OutputFile.c_str());
+  llvm::FileRemover ErrorRemover(ErrorFile.c_str());
+  llvm::Optional<StringRef> Redirects[] = {
+      {""}, // Stdin
+      OutputFile.str(),
+      ErrorFile.str(),
+  };
+  if (const int RC = llvm::sys::ExecuteAndWait(
+      ClangBinaryPath, PrintResourceDirArgs, {}, Redirects)) {
+    auto ErrorBuf = llvm::MemoryBuffer::getFile(ErrorFile.c_str());
+    llvm::errs() << ErrorBuf.get()->getBuffer();
+    return "";
+  }
+
+  auto OutputBuf = llvm::MemoryBuffer::getFile(OutputFile.c_str());
+  if (!OutputBuf)
+    return "";
+  StringRef Output = OutputBuf.get()->getBuffer().rtrim('\n');
+
+  Cache[ClangBinaryPath] = Output.str();
+  return Cache[ClangBinaryPath];
+}
+
 DependencyScanningService::DependencyScanningService(
     ScanningMode Mode, ScanningOutputFormat Format, bool ReuseFileManager,
     bool SkipExcludedPPRanges)
diff --git a/clang/tools/clang-scan-deps/ClangScanDeps.cpp b/clang/tools/clang-scan-deps/ClangScanDeps.cpp
--- a/clang/tools/clang-scan-deps/ClangScanDeps.cpp
+++ b/clang/tools/clang-scan-deps/ClangScanDeps.cpp
@@ -14,16 +14,12 @@
 #include "clang/Tooling/JSONCompilationDatabase.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/Twine.h"
-#include "llvm/Support/CommandLine.h"
-#include "llvm/Support/FileUtilities.h"
 #include "llvm/Support/InitLLVM.h"
 #include "llvm/Support/JSON.h"
-#include "llvm/Support/Program.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/ThreadPool.h"
 #include "llvm/Support/Threading.h"
 #include <mutex>
-#include <thread>
 
 using namespace clang;
 using namespace tooling::dependencies;
@@ -44,69 +40,6 @@
   raw_ostream &OS;
 };
 
-class ResourceDirectoryCache {
-public:
-  /// findResourceDir finds the resource directory relative to the clang
-  /// compiler being used in Args, by running it with "-print-resource-dir"
-  /// option and cache the results for reuse. \returns resource directory path
-  /// associated with the given invocation command or empty string if the
-  /// compiler path is NOT an absolute path.
-  StringRef findResourceDir(const tooling::CommandLineArguments &Args,
-                            bool ClangCLMode) {
-    if (Args.size() < 1)
-      return "";
-
-    const std::string &ClangBinaryPath = Args[0];
-    if (!llvm::sys::path::is_absolute(ClangBinaryPath))
-      return "";
-
-    const std::string &ClangBinaryName =
-        std::string(llvm::sys::path::filename(ClangBinaryPath));
-
-    std::unique_lock<std::mutex> LockGuard(CacheLock);
-    const auto &CachedResourceDir = Cache.find(ClangBinaryPath);
-    if (CachedResourceDir != Cache.end())
-      return CachedResourceDir->second;
-
-    std::vector<StringRef> PrintResourceDirArgs{ClangBinaryName};
-    if (ClangCLMode)
-      PrintResourceDirArgs.push_back("/clang:-print-resource-dir");
-    else
-      PrintResourceDirArgs.push_back("-print-resource-dir");
-
-    llvm::SmallString<64> OutputFile, ErrorFile;
-    llvm::sys::fs::createTemporaryFile("print-resource-dir-output",
-                                       "" /*no-suffix*/, OutputFile);
-    llvm::sys::fs::createTemporaryFile("print-resource-dir-error",
-                                       "" /*no-suffix*/, ErrorFile);
-    llvm::FileRemover OutputRemover(OutputFile.c_str());
-    llvm::FileRemover ErrorRemover(ErrorFile.c_str());
-    llvm::Optional<StringRef> Redirects[] = {
-        {""}, // Stdin
-        OutputFile.str(),
-        ErrorFile.str(),
-    };
-    if (const int RC = llvm::sys::ExecuteAndWait(
-            ClangBinaryPath, PrintResourceDirArgs, {}, Redirects)) {
-      auto ErrorBuf = llvm::MemoryBuffer::getFile(ErrorFile.c_str());
-      llvm::errs() << ErrorBuf.get()->getBuffer();
-      return "";
-    }
-
-    auto OutputBuf = llvm::MemoryBuffer::getFile(OutputFile.c_str());
-    if (!OutputBuf)
-      return "";
-    StringRef Output = OutputBuf.get()->getBuffer().rtrim('\n');
-
-    Cache[ClangBinaryPath] = Output.str();
-    return Cache[ClangBinaryPath];
-  }
-
-private:
-  std::map<std::string, std::string> Cache;
-  std::mutex CacheLock;
-};
-
 llvm::cl::opt<bool> Help("h", llvm::cl::desc("Alias for -help"),
                          llvm::cl::Hidden);