[llvm] Reland "[InstCombine] Fold (sub nuw X, (Y << nuw Z)) >>u exact Z --> (X >>u exact Z) sub nuw Y" (PR #93571)

[Yingwei Zheng via llvm-commits]

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@@ -466,6 +466,33 @@ define i32 @shl_sub_lshr(i32 %x, i32 %c, i32 %y) {
   ret i32 %lshr
 }
 
+define i32 @shl_sub_lshr_reverse(i32 %x, i32 %c, i32 %y) {
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dtcxzyw wrote:

Please add a test without nsw flag as well.


https://github.com/llvm/llvm-project/pull/93571