no-irreducible-loops.ll 1.1 KB

1234567891011121314151617181920212223242526272829303132333435363738
  1. ; RUN: opt < %s -jump-threading -loop-rotate -instcombine -indvars -loop-unroll -simplifycfg -S -verify-dom-info -verify-loop-info > %t
  2. ; RUN: grep "store volatile" %t | count 3
  3. ; RUN: not grep "br label" %t
  4. ; Jump threading should not prevent this loop from being unrolled.
  5. target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
  6. target triple = "i386-apple-darwin9.6"
  7. @v1 = external global i32 ; <i32*> [#uses=2]
  8. define i32 @unroll() nounwind {
  9. entry:
  10. br label %bb4
  11. bb: ; preds = %bb4
  12. %0 = icmp eq i32 %i.0, 0 ; <i1> [#uses=1]
  13. br i1 %0, label %bb1, label %bb2
  14. bb1: ; preds = %bb
  15. store volatile i32 1000, i32* @v1, align 4
  16. br label %bb3
  17. bb2: ; preds = %bb
  18. store volatile i32 1001, i32* @v1, align 4
  19. br label %bb3
  20. bb3: ; preds = %bb2, %bb1
  21. %1 = add i32 %i.0, 1 ; <i32> [#uses=1]
  22. br label %bb4
  23. bb4: ; preds = %bb3, %entry
  24. %i.0 = phi i32 [ 0, %entry ], [ %1, %bb3 ] ; <i32> [#uses=3]
  25. %2 = icmp sgt i32 %i.0, 2 ; <i1> [#uses=1]
  26. br i1 %2, label %bb5, label %bb
  27. bb5: ; preds = %bb4
  28. ret i32 0
  29. }