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      1 ; RUN: opt -indvars < %s
      2 ; PR9424: Attempt to use a SCEVCouldNotCompute object!
      3 ; The inner loop computes the Step and Start of the outer loop.
      4 ; Call that Vexit. The outer End value is max(2,Vexit), because
      5 ; the condition "icmp %4 < 2" does not guard the outer loop.
      6 ; SCEV knows that Vexit has range [2,4], so End == Vexit == Start.
      7 ; Now we have ExactBECount == 0. However, MinStart == 2 and MaxEnd == 4.
      8 ; Since the stride is variable and may wrap, we cannot compute
      9 ; MaxBECount. SCEV should override MaxBECount with ExactBECount.
     10 
     11 define void @bar() nounwind {
     12 entry:
     13   %. = select i1 undef, i32 2, i32 1
     14   br label %"5.preheader"
     15 
     16 "4":                                              ; preds = %"5.preheader", %"4"
     17   %0 = phi i32 [ 0, %"5.preheader" ], [ %1, %"4" ]
     18   %1 = add nsw i32 %0, 1
     19   %2 = icmp sgt i32 %., %1
     20   br i1 %2, label %"4", label %"9"
     21 
     22 "9":                                              ; preds = %"4"
     23   %3 = add i32 %6, 1
     24   %4 = add i32 %3, %1
     25   %5 = icmp slt i32 %4, 2
     26   br i1 %5, label %"5.preheader", label %return
     27 
     28 "5.preheader":                                    ; preds = %"9", %entry
     29   %6 = phi i32 [ 0, %entry ], [ %4, %"9" ]
     30   br label %"4"
     31 
     32 return:                                           ; preds = %"9"
     33   ret void
     34 }
     35