[llvm] [FileCheck] Use move semantics instead of std::swap. NFC. (PR #123304)

[Jay Foad via llvm-commits]

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@@ -837,8 +837,9 @@ struct FileCheckString {
   /// Hold the DAG/NOT strings occurring in the input file.
   std::vector<DagNotPrefixInfo> DagNotStrings;
 
-  FileCheckString(const Pattern &P, StringRef S, SMLoc L)
-      : Pat(P), Prefix(S), Loc(L) {}
+  FileCheckString(const Pattern &P, StringRef S, SMLoc L,
+                  std::vector<DagNotPrefixInfo> &&D)
+      : Pat(P), Prefix(S), Loc(L), DagNotStrings(std::move(D)) {}
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jayfoad wrote:

Good idea. Done.

https://github.com/llvm/llvm-project/pull/123304