1; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py
2; RUN: opt < %s -analyze -enable-new-pm=0 -scalar-evolution -scalar-evolution-classify-expressions=0 | FileCheck %s
3; RUN: opt < %s -disable-output "-passes=print<scalar-evolution>" -scalar-evolution-classify-expressions=0 2>&1 | FileCheck %s
4
5; Trip counts with trivial exit conditions.
6
7define void @a(i64 %n) nounwind {
8; CHECK-LABEL: 'a'
9; CHECK-NEXT:  Determining loop execution counts for: @a
10; CHECK-NEXT:  Loop %loop: Unpredictable backedge-taken count.
11; CHECK-NEXT:  Loop %loop: Unpredictable max backedge-taken count.
12; CHECK-NEXT:  Loop %loop: Unpredictable predicated backedge-taken count.
13;
14entry:
15  %t0 = icmp sgt i64 %n, 0
16  br i1 %t0, label %loop, label %return
17
18loop:
19  %i = phi i64 [ %i.next, %loop ], [ 0, %entry ]
20  %i.next = add nsw i64 %i, 1
21  %exitcond = icmp eq i64 %i.next, %n
22  br i1 false, label %return, label %loop
23
24return:
25  ret void
26}
27define void @b(i64 %n) nounwind {
28; CHECK-LABEL: 'b'
29; CHECK-NEXT:  Determining loop execution counts for: @b
30; CHECK-NEXT:  Loop %loop: backedge-taken count is false
31; CHECK-NEXT:  Loop %loop: max backedge-taken count is false
32; CHECK-NEXT:  Loop %loop: Predicated backedge-taken count is false
33; CHECK-NEXT:   Predicates:
34; CHECK:       Loop %loop: Trip multiple is 1
35;
36entry:
37  %t0 = icmp sgt i64 %n, 0
38  br i1 %t0, label %loop, label %return
39
40loop:
41  %i = phi i64 [ %i.next, %loop ], [ 0, %entry ]
42  %i.next = add nsw i64 %i, 1
43  %exitcond = icmp eq i64 %i.next, %n
44  br i1 true, label %return, label %loop
45
46return:
47  ret void
48}
49define void @c(i64 %n) nounwind {
50; CHECK-LABEL: 'c'
51; CHECK-NEXT:  Determining loop execution counts for: @c
52; CHECK-NEXT:  Loop %loop: backedge-taken count is false
53; CHECK-NEXT:  Loop %loop: max backedge-taken count is false
54; CHECK-NEXT:  Loop %loop: Predicated backedge-taken count is false
55; CHECK-NEXT:   Predicates:
56; CHECK:       Loop %loop: Trip multiple is 1
57;
58entry:
59  %t0 = icmp sgt i64 %n, 0
60  br i1 %t0, label %loop, label %return
61
62loop:
63  %i = phi i64 [ %i.next, %loop ], [ 0, %entry ]
64  %i.next = add nsw i64 %i, 1
65  %exitcond = icmp eq i64 %i.next, %n
66  br i1 false, label %loop, label %return
67
68return:
69  ret void
70}
71define void @d(i64 %n) nounwind {
72; CHECK-LABEL: 'd'
73; CHECK-NEXT:  Determining loop execution counts for: @d
74; CHECK-NEXT:  Loop %loop: Unpredictable backedge-taken count.
75; CHECK-NEXT:  Loop %loop: Unpredictable max backedge-taken count.
76; CHECK-NEXT:  Loop %loop: Unpredictable predicated backedge-taken count.
77;
78entry:
79  %t0 = icmp sgt i64 %n, 0
80  br i1 %t0, label %loop, label %return
81
82loop:
83  %i = phi i64 [ %i.next, %loop ], [ 0, %entry ]
84  %i.next = add nsw i64 %i, 1
85  %exitcond = icmp eq i64 %i.next, %n
86  br i1 true, label %loop, label %return
87
88return:
89  ret void
90}
91
92; Trip counts for non-polynomial iterations. It's theoretically possible
93; to compute a maximum count for these, but short of that, ScalarEvolution
94; should return unknown.
95
96; PR7416
97declare i1 @g() nounwind
98
99define void @nonpolynomial() {
100; CHECK-LABEL: 'nonpolynomial'
101; CHECK-NEXT:  Determining loop execution counts for: @nonpolynomial
102; CHECK-NEXT:  Loop %loophead: Unpredictable backedge-taken count.
103; CHECK-NEXT:  Loop %loophead: Unpredictable max backedge-taken count.
104; CHECK-NEXT:  Loop %loophead: Unpredictable predicated backedge-taken count.
105;
106entry:
107  br label %loophead
108loophead:
109  %x = phi i32 [0, %entry], [%x.1, %bb1], [%x.2, %bb2]
110  %y = icmp slt i32 %x, 100
111  br i1 %y, label %loopbody, label %retbb
112loopbody:
113  %z = call i1 @g()
114  br i1 %z, label %bb1, label %bb2
115bb1:
116  %x.1 = add i32 %x, 2
117  br label %loophead
118bb2:
119  %x.2 = add i32 %x, 3
120  br label %loophead
121retbb:
122  ret void
123}
124
125; PHI nodes with all constant operands.
126
127define void @constant_phi_operands() nounwind {
128; CHECK-LABEL: 'constant_phi_operands'
129; CHECK-NEXT:  Determining loop execution counts for: @constant_phi_operands
130; CHECK-NEXT:  Loop %loop: backedge-taken count is 1
131; CHECK-NEXT:  Loop %loop: max backedge-taken count is 1
132; CHECK-NEXT:  Loop %loop: Predicated backedge-taken count is 1
133; CHECK-NEXT:   Predicates:
134; CHECK:       Loop %loop: Trip multiple is 2
135;
136entry:
137  br label %loop
138
139loop:
140  %i = phi i64 [ 1, %loop ], [ 0, %entry ]
141  %exitcond = icmp eq i64 %i, 1
142  br i1 %exitcond, label %return, label %loop
143
144return:
145  ret void
146}
147
148; PR16130: Loop exit depends on an 'or' expression.
149; One side of the expression test against a value that will be skipped.
150; We can't assume undefined behavior just because we have an NSW flag.
151;
152define void @exit_orcond_nsw(i32 *%a) nounwind {
153; CHECK-LABEL: 'exit_orcond_nsw'
154; CHECK-NEXT:  Determining loop execution counts for: @exit_orcond_nsw
155; CHECK-NEXT:  Loop %for.body.i: Unpredictable backedge-taken count.
156; CHECK-NEXT:  Loop %for.body.i: max backedge-taken count is 1
157; CHECK-NEXT:  Loop %for.body.i: Unpredictable predicated backedge-taken count.
158;
159entry:
160  br label %for.body.i
161
162for.body.i:                                       ; preds = %for.body.i, %entry
163  %b.01.i = phi i32 [ 0, %entry ], [ %add.i, %for.body.i ]
164  %tobool.i = icmp ne i32 %b.01.i, 0
165  %add.i = add nsw i32 %b.01.i, 8
166  %cmp.i = icmp eq i32 %add.i, 13
167  %or.cond = or i1 %tobool.i, %cmp.i
168  br i1 %or.cond, label %exit, label %for.body.i
169
170exit:                                     ; preds = %for.body.i
171  %b.01.i.lcssa = phi i32 [ %b.01.i, %for.body.i ]
172  store i32 %b.01.i.lcssa, i32* %a, align 4
173  ret void
174}
175