demand_shrink_nsw.ll 850 B

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  1. ; RUN: opt -instcombine -o - -S %s | FileCheck %s
  2. ; The constant at %v35 should be shrunk, but this must lead to the nsw flag of
  3. ; %v43 getting removed so that %v44 is not illegally optimized away.
  4. ; CHECK-LABEL: @foo
  5. ; CHECK: %v35 = add nuw i32 %v34, 1362915575
  6. ; ...
  7. ; CHECK: add nuw i32 %v42, 1533579450
  8. ; CHECK-NEXT: %v44 = or i32 %v43, -2147483648
  9. ; CHECK-NEXT: %v45 = xor i32 %v44, 749011377
  10. ; CHECK-NEXT: ret i32 %v45
  11. define i32 @foo(i32 %arg) {
  12. %v33 = and i32 %arg, 223
  13. %v34 = xor i32 %v33, 29
  14. %v35 = add nuw i32 %v34, 3510399223
  15. %v37 = or i32 %v34, 1874836915
  16. %v38 = and i32 %v34, 221
  17. %v39 = xor i32 %v38, 1874836915
  18. %v40 = xor i32 %v37, %v39
  19. %v41 = shl nsw nuw i32 %v40, 1
  20. %v42 = sub i32 %v35, %v41
  21. %v43 = add nsw i32 %v42, 1533579450
  22. %v44 = or i32 %v43, -2147483648
  23. %v45 = xor i32 %v44, 749011377
  24. ret i32 %v45
  25. }