[JITLink] Use unique_function rather than std::function for JITLink passes.

Passes aren't expected to be copied, and switching to unique_function allows
them to capture values with move-only types.

diff --git a/llvm/include/llvm/ExecutionEngine/JITLink/JITLink.h b/llvm/include/llvm/ExecutionEngine/JITLink/JITLink.h
index f9d6679..1123b35 100644 (file)
--- a/llvm/include/llvm/ExecutionEngine/JITLink/JITLink.h
+++ b/llvm/include/llvm/ExecutionEngine/JITLink/JITLink.h
@@ -1627,7 +1627,7 @@ private:
 };
 
 /// A function for mutating LinkGraphs.
-using LinkGraphPassFunction = std::function<Error(LinkGraph &)>;
+using LinkGraphPassFunction = unique_function<Error(LinkGraph &)>;
 
 /// A list of LinkGraph passes.
 using LinkGraphPassList = std::vector<LinkGraphPassFunction>;