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; RUN: opt -indvars %s
; PR9424: Attempt to use a SCEVCouldNotCompute object!
; The inner loop computes the Step and Start of the outer loop.
; Call that Vexit. The outer End value is max(2,Vexit), because
; the condition "icmp %4 < 2" does not guard the outer loop.
; SCEV knows that Vexit has range [2,4], so End == Vexit == Start.
; Now we have ExactBECount == 0. However, MinStart == 2 and MaxEnd == 4.
; Since the stride is variable and may wrap, we cannot compute
; MaxBECount. SCEV should override MaxBECount with ExactBECount.
define void @bar() nounwind {
entry:
%. = select i1 undef, i32 2, i32 1
br label %"5.preheader"
"4": ; preds = %"5.preheader", %"4"
%0 = phi i32 [ 0, %"5.preheader" ], [ %1, %"4" ]
%1 = add nsw i32 %0, 1
%2 = icmp sgt i32 %., %1
br i1 %2, label %"4", label %"9"
"9": ; preds = %"4"
%3 = add i32 %6, 1
%4 = add i32 %3, %1
%5 = icmp slt i32 %4, 2
br i1 %5, label %"5.preheader", label %return
"5.preheader": ; preds = %"9", %entry
%6 = phi i32 [ 0, %entry ], [ %4, %"9" ]
br label %"4"
return: ; preds = %"9"
ret void
}
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