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      1 ; RUN: opt < %s -analyze -scalar-evolution | FileCheck %s
      2 
      3 ; CHECK: Determining loop execution counts for: @test
      4 ; CHECK: Loop %for.body: backedge-taken count is ((-2 + %len) /u 2)
      5 ; CHECK: Loop %for.body: max backedge-taken count is 1073741823
      6 
      7 define zeroext i16 @test(i16* nocapture %p, i32 %len) nounwind readonly {
      8 entry:
      9   %cmp2 = icmp sgt i32 %len, 1
     10   br i1 %cmp2, label %for.body.preheader, label %for.end
     11 
     12 for.body.preheader:                               ; preds = %entry
     13   br label %for.body
     14 
     15 for.body:                                         ; preds = %for.body, %for.body.preheader
     16   %p.addr.05 = phi i16* [ %incdec.ptr, %for.body ], [ %p, %for.body.preheader ]
     17   %len.addr.04 = phi i32 [ %sub, %for.body ], [ %len, %for.body.preheader ]
     18   %res.03 = phi i32 [ %add, %for.body ], [ 0, %for.body.preheader ]
     19   %incdec.ptr = getelementptr inbounds i16* %p.addr.05, i32 1
     20   %0 = load i16* %p.addr.05, align 2
     21   %conv = zext i16 %0 to i32
     22   %add = add i32 %conv, %res.03
     23   %sub = add nsw i32 %len.addr.04, -2
     24   %cmp = icmp sgt i32 %sub, 1
     25   br i1 %cmp, label %for.body, label %for.cond.for.end_crit_edge
     26 
     27 for.cond.for.end_crit_edge:                       ; preds = %for.body
     28   %extract.t = trunc i32 %add to i16
     29   br label %for.end
     30 
     31 for.end:                                          ; preds = %for.cond.for.end_crit_edge, %entry
     32   %res.0.lcssa.off0 = phi i16 [ %extract.t, %for.cond.for.end_crit_edge ], [ 0, %entry ]
     33   ret i16 %res.0.lcssa.off0
     34 }
     35 
     36