PhiEliminate.ll 827 B

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  1. ; Test a bunch of cases where the cfg simplification code should
  2. ; be able to fold PHI nodes into computation in common cases. Folding the PHI
  3. ; nodes away allows the branches to be eliminated, performing a simple form of
  4. ; 'if conversion'.
  5. ; RUN: opt < %s -simplifycfg -S > %t.xform
  6. ; RUN: not grep phi %t.xform
  7. ; RUN: grep ret %t.xform
  8. declare void @use(i1)
  9. declare void @use.upgrd.1(i32)
  10. define void @test(i1 %c, i32 %V, i32 %V2) {
  11. ; <label>:0
  12. br i1 %c, label %T, label %F
  13. T: ; preds = %0
  14. br label %F
  15. F: ; preds = %T, %0
  16. %B1 = phi i1 [ true, %0 ], [ false, %T ] ; <i1> [#uses=1]
  17. %I6 = phi i32 [ %V, %0 ], [ 0, %T ] ; <i32> [#uses=1]
  18. call void @use( i1 %B1 )
  19. call void @use.upgrd.1( i32 %I6 )
  20. ret void
  21. }