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1; RUN: opt < %s -loop-deletion -S | FileCheck %s
2; RUN: opt < %s -passes='require<scalar-evolution>,loop(loop-deletion)' -S | FileCheck %s
3
4; ScalarEvolution can prove the loop iteration is finite, even though
5; it can't represent the exact trip count as an expression. That's
6; good enough to let the loop be deleted.
7
8; CHECK:      entry:
9; CHECK-NEXT:   br label %return
10
11; CHECK:      return:
12; CHECK-NEXT:   ret void
13
14define void @foo(i64 %n, i64 %m) nounwind {
15entry:
16  br label %bb
17
18bb:
19  %x.0 = phi i64 [ 0, %entry ], [ %t0, %bb ]
20  %t0 = add i64 %x.0, 1
21  %t1 = icmp slt i64 %x.0, %n
22  %t3 = icmp sgt i64 %x.0, %m
23  %t4 = and i1 %t1, %t3
24  br i1 %t4, label %bb, label %return
25
26return:
27  ret void
28}
29