[llvm] Add option to dump IR to files instead of stderr (PR #66412)

[Arthur Eubanks via llvm-commits]

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@@ -103,6 +103,13 @@ static cl::list<std::string>
                             "options"),
                    cl::CommaSeparated, cl::Hidden);
 
+static cl::opt<std::string> IRDumpDirectory(
+    "ir-dump-directory",
+    llvm::cl::desc("If specified, IR printed using the "
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aeubanks wrote:

`llvm::` is unnecessary

https://github.com/llvm/llvm-project/pull/66412