dead-phi.ll 443 B

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  1. ; RUN: opt < %s -loop-reduce -S | grep phi | count 1
  2. define void @foo(i32 %n) {
  3. entry:
  4. br label %loop
  5. loop:
  6. %i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
  7. ; These three instructions form an isolated cycle and can be deleted.
  8. %j = phi i32 [ 0, %entry ], [ %j.y, %loop ]
  9. %j.x = add i32 %j, 1
  10. %j.y = mul i32 %j.x, 2
  11. %i.next = add i32 %i, 1
  12. %c = icmp ne i32 %i.next, %n
  13. br i1 %c, label %loop, label %exit
  14. exit:
  15. ret void
  16. }