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; RUN: opt < %s -analyze -scalar-evolution | FileCheck %s
; CHECK: Determining loop execution counts for: @test
; CHECK: Loop %for.body: backedge-taken count is ((-2 + %len) /u 2)
; CHECK: Loop %for.body: max backedge-taken count is 1073741823
define zeroext i16 @test(i16* nocapture %p, i32 %len) nounwind readonly {
entry:
%cmp2 = icmp sgt i32 %len, 1
br i1 %cmp2, label %for.body.preheader, label %for.end
for.body.preheader: ; preds = %entry
br label %for.body
for.body: ; preds = %for.body, %for.body.preheader
%p.addr.05 = phi i16* [ %incdec.ptr, %for.body ], [ %p, %for.body.preheader ]
%len.addr.04 = phi i32 [ %sub, %for.body ], [ %len, %for.body.preheader ]
%res.03 = phi i32 [ %add, %for.body ], [ 0, %for.body.preheader ]
%incdec.ptr = getelementptr inbounds i16* %p.addr.05, i32 1
%0 = load i16* %p.addr.05, align 2
%conv = zext i16 %0 to i32
%add = add i32 %conv, %res.03
%sub = add nsw i32 %len.addr.04, -2
%cmp = icmp sgt i32 %sub, 1
br i1 %cmp, label %for.body, label %for.cond.for.end_crit_edge
for.cond.for.end_crit_edge: ; preds = %for.body
%extract.t = trunc i32 %add to i16
br label %for.end
for.end: ; preds = %for.cond.for.end_crit_edge, %entry
%res.0.lcssa.off0 = phi i16 [ %extract.t, %for.cond.for.end_crit_edge ], [ 0, %entry ]
ret i16 %res.0.lcssa.off0
}
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