[llvm] [libLTO] add thinlto caching flags to libLTO (PR #168567)

[Wael Yehia via llvm-commits]

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@@ -44,6 +45,29 @@ static cl::opt<bool> EnableFreestanding(
     "lto-freestanding", cl::init(false),
     cl::desc("Enable Freestanding (disable builtins / TLI) during LTO"));
 
+static cl::opt<std::string> ThinLTOCacheDir(
+    "thinlto-cache-dir",
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w2yehia wrote:

done

https://github.com/llvm/llvm-project/pull/168567