[llvm] [TailRecElim] Introduce support for shift accumulator optimization (PR #181331)

[Aiden Grossman via llvm-commits]

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@@ -82,12 +82,13 @@
 #include "llvm/Transforms/Scalar.h"
 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
 #include <cmath>
+#include <variant>
 using namespace llvm;
 
 #define DEBUG_TYPE "tailcallelim"
 
 STATISTIC(NumEliminated, "Number of tail calls removed");
-STATISTIC(NumRetDuped,   "Number of return duplicated");
+STATISTIC(NumRetDuped, "Number of return duplicated");
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boomanaiden154 wrote:

It looks like there's a lot of drive-by formatting in this file? That should probably be reverted to make the actual changes easier to see.

https://github.com/llvm/llvm-project/pull/181331