[llvm] [DAG] Remove OneUse restriction on sext when folding (shl (sext (add_nsw x, c1)), c2) (PR #68972)

[via llvm-commits]

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@@ -21,10 +21,11 @@ define i32 @PR65895() {
 ; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
 ; CHECK-NEXT:    jmp .LBB0_2
 ; CHECK-NEXT:  .LBB0_3: # %for.end
+; CHECK-NEXT:    movzbl %al, %ecx
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LiqinWeng wrote:

done

https://github.com/llvm/llvm-project/pull/68972