1; RUN: opt -S -loop-unroll -unroll-runtime < %s | FileCheck %s
2
3; Epilog unroll allows to keep PHI constant value.
4; For the test this means that after unroll XOR could be deleted.
5; Check that we do epilogue reminder here.
6
7; CHECK-LABEL: const_phi_val
8; CHECK:  for.body.epil
9
10; Function Attrs: norecurse nounwind uwtable
11define void @const_phi_val(i32 %i0, i32* nocapture %a) {
12entry:
13  %cmp6 = icmp slt i32 %i0, 1000
14  br i1 %cmp6, label %for.body.preheader, label %for.end
15
16for.body.preheader:                               ; preds = %entry
17  %tmp = sext i32 %i0 to i64
18  br label %for.body
19
20for.body:                                         ; preds = %for.body, %for.body.preheader
21  %indvars.iv = phi i64 [ %tmp, %for.body.preheader ], [ %indvars.iv.next, %for.body ]
22  %s.08 = phi i32 [ 0, %for.body.preheader ], [ %xor, %for.body ]
23  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
24  store i32 %s.08, i32* %arrayidx, align 4
25  %xor = xor i32 %s.08, 1
26  %indvars.iv.next = add nsw i64 %indvars.iv, 1
27  %exitcond = icmp eq i64 %indvars.iv.next, 1000
28  br i1 %exitcond, label %for.end.loopexit, label %for.body
29
30for.end.loopexit:                                 ; preds = %for.body
31  br label %for.end
32
33for.end:                                          ; preds = %for.end.loopexit, %entry
34  ret void
35}
36
37; When there is no phi with const coming from preheader,
38; there is no need to do epilogue unrolling.
39
40; CHECK-LABEL: var_phi_val
41; CHECK:  for.body.prol
42
43; Function Attrs: norecurse nounwind uwtable
44define void @var_phi_val(i32 %i0, i32* nocapture %a) {
45entry:
46  %cmp6 = icmp slt i32 %i0, 1000
47  br i1 %cmp6, label %for.body.preheader, label %for.end
48
49for.body.preheader:                               ; preds = %entry
50  %tmp = sext i32 %i0 to i64
51  br label %for.body
52
53for.body:                                         ; preds = %for.body, %for.body.preheader
54  %indvars.iv = phi i64 [ %tmp, %for.body.preheader ], [ %indvars.iv.next, %for.body ]
55  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
56  %indvars.iv.next = add nsw i64 %indvars.iv, 1
57  %exitcond = icmp eq i64 %indvars.iv.next, 1000
58  br i1 %exitcond, label %for.end.loopexit, label %for.body
59
60for.end.loopexit:                                 ; preds = %for.body
61  br label %for.end
62
63for.end:                                          ; preds = %for.end.loopexit, %entry
64  ret void
65}
66