xref: /llvm-project/llvm/test/Analysis/ScalarEvolution/addrec-sub-nsw.ll (revision 8b5b294ec2cf876bc5eb5bd5fcb56ef487e36d60)
1; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 2
2; RUN: opt -disable-output "-passes=print<scalar-evolution>" < %s 2>&1 | FileCheck %s
3
4define i32 @test_1_non_negative(i32 %n) {
5; CHECK-LABEL: 'test_1_non_negative'
6; CHECK-NEXT:  Classifying expressions for: @test_1_non_negative
7; CHECK-NEXT:    %i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
8; CHECK-NEXT:    --> {0,+,1}<nuw><nsw><%loop> U: [0,2147483647) S: [0,2147483647) Exits: (-1 + (1 smax %n))<nsw> LoopDispositions: { %loop: Computable }
9; CHECK-NEXT:    %a = sub i32 %n, %i
10; CHECK-NEXT:    --> {%n,+,-1}<nw><%loop> U: full-set S: full-set Exits: (1 + (-1 * (1 smax %n))<nsw> + %n) LoopDispositions: { %loop: Computable }
11; CHECK-NEXT:    %i.next = add nuw nsw i32 %i, 1
12; CHECK-NEXT:    --> {1,+,1}<nuw><nsw><%loop> U: [1,-2147483648) S: [1,-2147483648) Exits: (1 smax %n) LoopDispositions: { %loop: Computable }
13; CHECK-NEXT:  Determining loop execution counts for: @test_1_non_negative
14; CHECK-NEXT:  Loop %loop: backedge-taken count is (-1 + (1 smax %n))<nsw>
15; CHECK-NEXT:  Loop %loop: constant max backedge-taken count is i32 2147483646
16; CHECK-NEXT:  Loop %loop: symbolic max backedge-taken count is (-1 + (1 smax %n))<nsw>
17; CHECK-NEXT:  Loop %loop: Trip multiple is 1
18;
19entry:
20  %precond = icmp sge i32 %n, 0
21  br i1 %precond, label %loop, label %fail
22
23loop:
24  %i = phi i32 [0, %entry], [%i.next, %loop]                      ; 0...n-1
25  %a = sub i32 %n, %i                                             ; n...0
26  %i.next = add nuw nsw i32 %i, 1
27  %cond = icmp slt i32 %i.next, %n
28  br i1 %cond, label %loop, label %exit
29
30fail:
31  ret i32 -1
32
33exit:
34  ret i32 0
35}
36
37define i32 @test_2_non_positive(i32 %n) {
38; CHECK-LABEL: 'test_2_non_positive'
39; CHECK-NEXT:  Classifying expressions for: @test_2_non_positive
40; CHECK-NEXT:    %minus.n = mul i32 %n, -1
41; CHECK-NEXT:    --> (-1 * %n) U: full-set S: full-set
42; CHECK-NEXT:    %i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
43; CHECK-NEXT:    --> {0,+,1}<nuw><nsw><%loop> U: [0,2147483647) S: [0,2147483647) Exits: (-1 + (1 smax %n))<nsw> LoopDispositions: { %loop: Computable }
44; CHECK-NEXT:    %minus.i = mul i32 %i, -1
45; CHECK-NEXT:    --> {0,+,-1}<nsw><%loop> U: [-2147483646,1) S: [-2147483646,1) Exits: (1 + (-1 * (1 smax %n))<nsw>)<nsw> LoopDispositions: { %loop: Computable }
46; CHECK-NEXT:    %a = sub i32 %minus.n, %minus.i
47; CHECK-NEXT:    --> {(-1 * %n),+,1}<nw><%loop> U: full-set S: full-set Exits: (-1 + (-1 * %n) + (1 smax %n)) LoopDispositions: { %loop: Computable }
48; CHECK-NEXT:    %i.next = add nuw nsw i32 %i, 1
49; CHECK-NEXT:    --> {1,+,1}<nuw><nsw><%loop> U: [1,-2147483648) S: [1,-2147483648) Exits: (1 smax %n) LoopDispositions: { %loop: Computable }
50; CHECK-NEXT:  Determining loop execution counts for: @test_2_non_positive
51; CHECK-NEXT:  Loop %loop: backedge-taken count is (-1 + (1 smax %n))<nsw>
52; CHECK-NEXT:  Loop %loop: constant max backedge-taken count is i32 2147483646
53; CHECK-NEXT:  Loop %loop: symbolic max backedge-taken count is (-1 + (1 smax %n))<nsw>
54; CHECK-NEXT:  Loop %loop: Trip multiple is 1
55;
56entry:
57  %precond = icmp sge i32 %n, 0
58  %minus.n = mul i32 %n, -1
59  br i1 %precond, label %loop, label %fail
60
61loop:
62  %i = phi i32 [0, %entry], [%i.next, %loop]                      ; 0...n-1
63  %minus.i = mul i32 %i, -1                                       ; -(n-1)...0
64  %a = sub i32 %minus.n, %minus.i                                 ; -n...-1
65  %i.next = add nuw nsw i32 %i, 1
66  %cond = icmp slt i32 %i.next, %n
67  br i1 %cond, label %loop, label %exit
68
69fail:
70  ret i32 -1
71
72exit:
73  ret i32 0
74}
75