diff --git a/llvm/include/llvm/Support/CachePruning.h b/llvm/include/llvm/Support/CachePruning.h
--- a/llvm/include/llvm/Support/CachePruning.h
+++ b/llvm/include/llvm/Support/CachePruning.h
@@ -15,6 +15,7 @@
 #define LLVM_SUPPORT_CACHE_PRUNING_H
 
 #include "llvm/ADT/Optional.h"
+#include "llvm/ADT/Twine.h"
 #include <chrono>
 
 namespace llvm {
@@ -71,9 +72,10 @@
 /// occurred, i.e. if Policy.Interval was expired.
 ///
 /// As a safeguard against data loss if the user specifies the wrong directory
-/// as their cache directory, this function will ignore files not matching the
-/// pattern "llvmcache-*".
-bool pruneCache(StringRef Path, CachePruningPolicy Policy);
+/// as their cache directory, this function will ignore files whose name does
+/// not start with Prefix.
+bool pruneCache(StringRef Path, CachePruningPolicy Policy,
+                Twine Prefix = "llvmcache");
 
 } // namespace llvm
 
diff --git a/llvm/lib/Support/CachePruning.cpp b/llvm/lib/Support/CachePruning.cpp
--- a/llvm/lib/Support/CachePruning.cpp
+++ b/llvm/lib/Support/CachePruning.cpp
@@ -141,7 +141,8 @@
 }
 
 /// Prune the cache of files that haven't been accessed in a long time.
-bool llvm::pruneCache(StringRef Path, CachePruningPolicy Policy) {
+bool llvm::pruneCache(StringRef Path, CachePruningPolicy Policy,
+                      Twine Prefix) {
   using namespace std::chrono;
 
   if (Path.empty())
@@ -167,7 +168,7 @@
 
   // Try to stat() the timestamp file.
   SmallString<128> TimestampFile(Path);
-  sys::path::append(TimestampFile, "llvmcache.timestamp");
+  sys::path::append(TimestampFile, Prefix + ".timestamp");
   sys::fs::file_status FileStatus;
   const auto CurrentTime = system_clock::now();
   if (auto EC = sys::fs::status(TimestampFile, FileStatus)) {
@@ -211,11 +212,11 @@
   // Walk all of the files within this directory.
   for (sys::fs::directory_iterator File(CachePathNative, EC), FileEnd;
        File != FileEnd && !EC; File.increment(EC)) {
-    // Ignore any files not beginning with the string "llvmcache-". This
+    // Ignore any files not beginning with the prefix string. This
     // includes the timestamp file as well as any files created by the user.
     // This acts as a safeguard against data loss if the user specifies the
     // wrong directory as their cache directory.
-    if (!sys::path::filename(File->path()).startswith("llvmcache-"))
+    if (!sys::path::filename(File->path()).startswith((Prefix + "-").str()))
       continue;
 
     // Look at this file. If we can't stat it, there's nothing interesting