xref: /llvm-project/llvm/test/Analysis/ScalarEvolution/implied-via-addition.ll (revision 0ab368c5735328298d99dcfb80da12e7be028583)
1; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 5
2; RUN: opt < %s -disable-output -passes="print<scalar-evolution>" \
3; RUN:   -scalar-evolution-classify-expressions=0 2>&1 | FileCheck %s
4
5define void @implied1(i32 %n) {
6; Prove that (n s> 1) ===> (n - 1 s> 0).
7; CHECK-LABEL: 'implied1'
8; CHECK-NEXT:  Determining loop execution counts for: @implied1
9; CHECK-NEXT:  Loop %header: backedge-taken count is (-2 + %n)
10; CHECK-NEXT:  Loop %header: constant max backedge-taken count is i32 2147483645
11; CHECK-NEXT:  Loop %header: symbolic max backedge-taken count is (-2 + %n)
12; CHECK-NEXT:  Loop %header: Trip multiple is 1
13;
14entry:
15  %cmp1 = icmp sgt i32 %n, 1
16  %n.minus.1 = sub nsw i32 %n, 1
17  call void @llvm.assume(i1 %cmp1)
18  br label %header
19
20header:
21  %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
22  %indvar.next = add i32 %indvar, 1
23  %exitcond = icmp sgt i32 %n.minus.1, %indvar.next
24  br i1 %exitcond, label %header, label %exit
25
26exit:
27  ret void
28}
29
30define void @implied1_neg(i32 %n) {
31; Prove that (n s> 0) =\=> (n - 1 s> 0).
32; CHECK-LABEL: 'implied1_neg'
33; CHECK-NEXT:  Determining loop execution counts for: @implied1_neg
34; CHECK-NEXT:  Loop %header: backedge-taken count is (-1 + (1 smax (-1 + %n)<nsw>))<nsw>
35; CHECK-NEXT:  Loop %header: constant max backedge-taken count is i32 2147483645
36; CHECK-NEXT:  Loop %header: symbolic max backedge-taken count is (-1 + (1 smax (-1 + %n)<nsw>))<nsw>
37; CHECK-NEXT:  Loop %header: Trip multiple is 1
38;
39entry:
40  %cmp1 = icmp sgt i32 %n, 0
41  %n.minus.1 = sub nsw i32 %n, 1
42  call void @llvm.assume(i1 %cmp1)
43  br label %header
44
45header:
46  %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
47  %indvar.next = add i32 %indvar, 1
48  %exitcond = icmp sgt i32 %n.minus.1, %indvar.next
49  br i1 %exitcond, label %header, label %exit
50
51exit:
52  ret void
53}
54
55define void @implied2(i32 %n) {
56; Prove that (n u>= -1) ===> (n + 1 u>= 0).
57; CHECK-LABEL: 'implied2'
58; CHECK-NEXT:  Determining loop execution counts for: @implied2
59; CHECK-NEXT:  Loop %header: Unpredictable backedge-taken count.
60; CHECK-NEXT:  Loop %header: Unpredictable constant max backedge-taken count.
61; CHECK-NEXT:  Loop %header: Unpredictable symbolic max backedge-taken count.
62; CHECK-NEXT:  Loop %header: Predicated backedge-taken count is (1 + (zext i32 %n to i64))<nuw><nsw>
63; CHECK-NEXT:   Predicates:
64; CHECK-NEXT:      {1,+,1}<%header> Added Flags: <nusw>
65; CHECK-NEXT:  Loop %header: Predicated constant max backedge-taken count is i64 4294967296
66; CHECK-NEXT:   Predicates:
67; CHECK-NEXT:      {1,+,1}<%header> Added Flags: <nusw>
68; CHECK-NEXT:  Loop %header: Predicated symbolic max backedge-taken count is (1 + (zext i32 %n to i64))<nuw><nsw>
69; CHECK-NEXT:   Predicates:
70; CHECK-NEXT:      {1,+,1}<%header> Added Flags: <nusw>
71;
72entry:
73  %cmp1 = icmp uge i32 %n, -1
74  %n.1 = add nuw i32 %n, 1
75  call void @llvm.assume(i1 %cmp1)
76  br label %header
77
78header:
79  %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
80  %indvar.next = add i32 %indvar, 1
81  %exitcond = icmp uge i32 %n.1, %indvar.next
82  br i1 %exitcond, label %header, label %exit
83
84exit:
85  ret void
86}
87
88define void @implied2_neg(i32 %n) {
89; Prove that (n u>= -1) =\=> (n - 1 s>= 0).
90; CHECK-LABEL: 'implied2_neg'
91; CHECK-NEXT:  Determining loop execution counts for: @implied2_neg
92; CHECK-NEXT:  Loop %header: backedge-taken count is (-1 + (1 smax %n))<nsw>
93; CHECK-NEXT:  Loop %header: constant max backedge-taken count is i32 2147483646
94; CHECK-NEXT:  Loop %header: symbolic max backedge-taken count is (-1 + (1 smax %n))<nsw>
95; CHECK-NEXT:  Loop %header: Trip multiple is 1
96;
97entry:
98  %cmp1 = icmp uge i32 %n, -1
99  %n.minus.1 = sub nuw nsw i32 %n, 1
100  call void @llvm.assume(i1 %cmp1)
101  br label %header
102
103header:
104  %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
105  %indvar.next = add i32 %indvar, 1
106  %exitcond = icmp sge i32 %n.minus.1, %indvar.next
107  br i1 %exitcond, label %header, label %exit
108
109exit:
110  ret void
111}
112