multiple-phis.ll 1.5 KB

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  1. ; RUN: opt -simplifycfg -S < %s | FileCheck %s
  2. ; It's not worthwhile to if-convert one of the phi nodes and leave
  3. ; the other behind, because that still requires a branch. If
  4. ; SimplifyCFG if-converts one of the phis, it should do both.
  5. ; CHECK: %div.high.addr.0 = select i1 %cmp1, i32 %div, i32 %high.addr.0
  6. ; CHECK-NEXT: %low.0.add2 = select i1 %cmp1, i32 %low.0, i32 %add2
  7. ; CHECK-NEXT: br label %while.cond
  8. define i32 @upper_bound(i32* %r, i32 %high, i32 %k) nounwind {
  9. entry:
  10. br label %while.cond
  11. while.cond: ; preds = %if.then, %if.else, %entry
  12. %high.addr.0 = phi i32 [ %high, %entry ], [ %div, %if.then ], [ %high.addr.0, %if.else ]
  13. %low.0 = phi i32 [ 0, %entry ], [ %low.0, %if.then ], [ %add2, %if.else ]
  14. %cmp = icmp ult i32 %low.0, %high.addr.0
  15. br i1 %cmp, label %while.body, label %while.end
  16. while.body: ; preds = %while.cond
  17. %add = add i32 %low.0, %high.addr.0
  18. %div = udiv i32 %add, 2
  19. %idxprom = zext i32 %div to i64
  20. %arrayidx = getelementptr inbounds i32, i32* %r, i64 %idxprom
  21. %0 = load i32, i32* %arrayidx
  22. %cmp1 = icmp ult i32 %k, %0
  23. br i1 %cmp1, label %if.then, label %if.else
  24. if.then: ; preds = %while.body
  25. br label %while.cond
  26. if.else: ; preds = %while.body
  27. %add2 = add i32 %div, 1
  28. br label %while.cond
  29. while.end: ; preds = %while.cond
  30. ret i32 %low.0
  31. }