[llvm/CAS] Fix the non-LLVM_ENABLE_ONDISK_CAS build

A couple of functions outside the `LLVM_ENABLE_ONDISK_CAS` guard were erroneous.

Author: akyrtzi

llvm/lib/CAS/ActionCaches.cpp

@@ -216,30 +216,17 @@ Error UnifiedOnDiskActionCache::putImpl(ArrayRef<uint8_t> Key,
       UniDB->getGraphDB().getDigest(*Observed));
 }
 
-#if LLVM_ENABLE_ONDISK_CAS
-
 Expected<std::unique_ptr<ActionCache>>
 cas::createOnDiskActionCache(StringRef Path) {
+#if LLVM_ENABLE_ONDISK_CAS
   return OnDiskActionCache::create(Path);
-}
-
-std::unique_ptr<ActionCache>
-cas::builtin::createActionCacheFromUnifiedOnDiskCache(
-    std::shared_ptr<ondisk::UnifiedOnDiskCache> UniDB) {
-  return std::make_unique<UnifiedOnDiskActionCache>(std::move(UniDB));
-}
-
-# else
-
-Expected<std::unique_ptr<ActionCache>>
-cas::createOnDiskActionCache(StringRef Path) {
+#else
   return createStringError(inconvertibleErrorCode(), "OnDiskCache is disabled");
+#endif
 }
 
 std::unique_ptr<ActionCache>
 cas::builtin::createActionCacheFromUnifiedOnDiskCache(
     std::shared_ptr<ondisk::UnifiedOnDiskCache> UniDB) {
-  return createStringError(inconvertibleErrorCode(), "OnDiskCache is disabled");
+  return std::make_unique<UnifiedOnDiskActionCache>(std::move(UniDB));
 }
-
-#endif /* LLVM_ENABLE_ONDISK_CAS */

llvm/lib/CAS/BuiltinCAS.cpp

@@ -83,7 +83,11 @@ Error BuiltinCAS::validate(const CASID &ID) {
 
 Expected<std::unique_ptr<ondisk::UnifiedOnDiskCache>>
 cas::builtin::createBuiltinUnifiedOnDiskCache(StringRef Path) {
+#if LLVM_ENABLE_ONDISK_CAS
   return ondisk::UnifiedOnDiskCache::open(Path, /*SizeLimit=*/std::nullopt,
                                           BuiltinCASContext::getHashName(),
                                           sizeof(HashType));
+#else
+  return createStringError(inconvertibleErrorCode(), "OnDiskCache is disabled");
+#endif
 }

llvm/lib/CAS/OnDiskCAS.cpp

@@ -147,9 +147,8 @@ bool cas::isOnDiskCASEnabled() {
 #endif
 }
 
-#if LLVM_ENABLE_ONDISK_CAS
-
 Expected<std::unique_ptr<ObjectStore>> cas::createOnDiskCAS(const Twine &Path) {
+#if LLVM_ENABLE_ONDISK_CAS
   // FIXME: An absolute path isn't really good enough. Should open a directory
   // and use openat() for files underneath.
   SmallString<256> AbsPath;
@@ -161,28 +160,17 @@ Expected<std::unique_ptr<ObjectStore>> cas::createOnDiskCAS(const Twine &Path) {
     AbsPath = StringRef(getDefaultOnDiskCASPath());
 
   return OnDiskCAS::open(AbsPath);
-}
-
-std::unique_ptr<ObjectStore>
-cas::builtin::createObjectStoreFromUnifiedOnDiskCache(
-    std::shared_ptr<ondisk::UnifiedOnDiskCache> UniDB) {
-  return std::make_unique<OnDiskCAS>(std::move(UniDB));
-}
-
-#else /* LLVM_ENABLE_ONDISK_CAS */
-
-Expected<std::unique_ptr<ObjectStore>> cas::createOnDiskCAS(const Twine &Path) {
+#else
   return createStringError(inconvertibleErrorCode(), "OnDiskCAS is disabled");
+#endif /* LLVM_ENABLE_ONDISK_CAS */
 }
 
 std::unique_ptr<ObjectStore>
 cas::builtin::createObjectStoreFromUnifiedOnDiskCache(
     std::shared_ptr<ondisk::UnifiedOnDiskCache> UniDB) {
-  return createStringError(inconvertibleErrorCode(), "OnDiskCAS is disabled");
+  return std::make_unique<OnDiskCAS>(std::move(UniDB));
 }
 
-#endif /* LLVM_ENABLE_ONDISK_CAS */
-
 static constexpr StringLiteral DefaultName = "cas";
 
 void cas::getDefaultOnDiskCASStableID(SmallVectorImpl<char> &Path) {