[llvm] [ADT] Add signed and unsigned mulHi and mulLo to APInt (PR #84719)

[Jay Foad via llvm-commits]

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@@ -10,6 +10,7 @@
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
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jayfoad wrote:

Is this still needed?

https://github.com/llvm/llvm-project/pull/84719