1; RUN: opt < %s -S -loop-unroll -unroll-runtime=true | FileCheck %s
2
3; Tests for unrolling loops with run-time trip counts
4
5; CHECK: unr.cmp{{.*}}:
6; CHECK: for.body.unr{{.*}}:
7; CHECK: for.body:
8; CHECK: br i1 %exitcond.7, label %for.end.loopexit{{.*}}, label %for.body
9
10define i32 @test(i32* nocapture %a, i32 %n) nounwind uwtable readonly {
11entry:
12  %cmp1 = icmp eq i32 %n, 0
13  br i1 %cmp1, label %for.end, label %for.body
14
15for.body:                                         ; preds = %for.body, %entry
16  %indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %entry ]
17  %sum.02 = phi i32 [ %add, %for.body ], [ 0, %entry ]
18  %arrayidx = getelementptr inbounds i32* %a, i64 %indvars.iv
19  %0 = load i32* %arrayidx, align 4
20  %add = add nsw i32 %0, %sum.02
21  %indvars.iv.next = add i64 %indvars.iv, 1
22  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
23  %exitcond = icmp eq i32 %lftr.wideiv, %n
24  br i1 %exitcond, label %for.end, label %for.body
25
26for.end:                                          ; preds = %for.body, %entry
27  %sum.0.lcssa = phi i32 [ 0, %entry ], [ %add, %for.body ]
28  ret i32 %sum.0.lcssa
29}
30
31
32; Still try to completely unroll loops with compile-time trip counts
33; even if the -unroll-runtime is specified
34
35; CHECK: for.body:
36; CHECK-NOT: for.body.unr:
37
38define i32 @test1(i32* nocapture %a) nounwind uwtable readonly {
39entry:
40  br label %for.body
41
42for.body:                                         ; preds = %for.body, %entry
43  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
44  %sum.01 = phi i32 [ 0, %entry ], [ %add, %for.body ]
45  %arrayidx = getelementptr inbounds i32* %a, i64 %indvars.iv
46  %0 = load i32* %arrayidx, align 4
47  %add = add nsw i32 %0, %sum.01
48  %indvars.iv.next = add i64 %indvars.iv, 1
49  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
50  %exitcond = icmp eq i32 %lftr.wideiv, 5
51  br i1 %exitcond, label %for.end, label %for.body
52
53for.end:                                          ; preds = %for.body
54  ret i32 %add
55}
56
57; This is test 2007-05-09-UnknownTripCount.ll which can be unrolled now
58; if the -unroll-runtime option is turned on
59
60; CHECK: bb72.2:
61
62define void @foo(i32 %trips) {
63entry:
64        br label %cond_true.outer
65
66cond_true.outer:
67        %indvar1.ph = phi i32 [ 0, %entry ], [ %indvar.next2, %bb72 ]
68        br label %bb72
69
70bb72:
71        %indvar.next2 = add i32 %indvar1.ph, 1
72        %exitcond3 = icmp eq i32 %indvar.next2, %trips
73        br i1 %exitcond3, label %cond_true138, label %cond_true.outer
74
75cond_true138:
76        ret void
77}
78
79
80; Test run-time unrolling for a loop that counts down by -2.
81
82; CHECK: for.body.unr:
83; CHECK: br i1 %cmp.7, label %for.cond.for.end_crit_edge{{.*}}, label %for.body
84
85define zeroext i16 @down(i16* nocapture %p, i32 %len) nounwind uwtable readonly {
86entry:
87  %cmp2 = icmp eq i32 %len, 0
88  br i1 %cmp2, label %for.end, label %for.body
89
90for.body:                                         ; preds = %for.body, %entry
91  %p.addr.05 = phi i16* [ %incdec.ptr, %for.body ], [ %p, %entry ]
92  %len.addr.04 = phi i32 [ %sub, %for.body ], [ %len, %entry ]
93  %res.03 = phi i32 [ %add, %for.body ], [ 0, %entry ]
94  %incdec.ptr = getelementptr inbounds i16* %p.addr.05, i64 1
95  %0 = load i16* %p.addr.05, align 2
96  %conv = zext i16 %0 to i32
97  %add = add i32 %conv, %res.03
98  %sub = add nsw i32 %len.addr.04, -2
99  %cmp = icmp eq i32 %sub, 0
100  br i1 %cmp, label %for.cond.for.end_crit_edge, label %for.body
101
102for.cond.for.end_crit_edge:                       ; preds = %for.body
103  %phitmp = trunc i32 %add to i16
104  br label %for.end
105
106for.end:                                          ; preds = %for.cond.for.end_crit_edge, %entry
107  %res.0.lcssa = phi i16 [ %phitmp, %for.cond.for.end_crit_edge ], [ 0, %entry ]
108  ret i16 %res.0.lcssa
109}
110