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| ; RUN: opt < %s -analyze -scalar-evolution | FileCheck %s
; CHECK: Loop %bb: backedge-taken count is ((-5 + %x) /u 3)
; CHECK: Loop %bb: max backedge-taken count is 1431655764
; ScalarEvolution can't compute a trip count because it doesn't know if
; dividing by the stride will have a remainder. This could theoretically
; be teaching it how to use a more elaborate trip count computation.
define i32 @f(i32 %x) nounwind readnone {
entry:
%0 = icmp ugt i32 %x, 4 ; <i1> [#uses=1]
br i1 %0, label %bb.nph, label %bb2
bb.nph: ; preds = %entry
br label %bb
bb: ; preds = %bb.nph, %bb1
%indvar = phi i32 [ 0, %bb.nph ], [ %indvar.next, %bb1 ] ; <i32> [#uses=2]
%tmp = mul i32 %indvar, -3 ; <i32> [#uses=1]
%x_addr.04 = add i32 %tmp, %x ; <i32> [#uses=1]
%1 = add i32 %x_addr.04, -3 ; <i32> [#uses=2]
br label %bb1
bb1: ; preds = %bb
%2 = icmp ugt i32 %1, 4 ; <i1> [#uses=1]
%indvar.next = add i32 %indvar, 1 ; <i32> [#uses=1]
br i1 %2, label %bb, label %bb1.bb2_crit_edge
bb1.bb2_crit_edge: ; preds = %bb1
%.lcssa = phi i32 [ %1, %bb1 ] ; <i32> [#uses=1]
br label %bb2
bb2: ; preds = %bb1.bb2_crit_edge, %entry
%x_addr.0.lcssa = phi i32 [ %.lcssa, %bb1.bb2_crit_edge ], [ %x, %entry ] ; <i32> [#uses=1]
ret i32 %x_addr.0.lcssa
}
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