[llvm] [InstCombine] Simplify `(add/sub (sub/add) (sub/add))` irrelivant of use-count (PR #105866)

[Nikita Popov via llvm-commits]

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@@ -2008,6 +2008,24 @@ static bool shouldMergeGEPs(GEPOperator &GEP, GEPOperator &Src) {
   return true;
 }
 
+Instruction *InstCombinerImpl::foldAddLikeCommutative(Value *LHS, Value *RHS,
+                                                      bool NSW, bool NUW) {
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nikic wrote:

Please move this into InstCombineAddSub.cpp. It will make it easier to move folds if necessary.

https://github.com/llvm/llvm-project/pull/105866