1; REQUIRES: asserts
2; RUN: opt < %s -loop-interchange -cache-line-size=64 -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -pass-remarks-output=%t \
3; RUN:     -pass-remarks=loop-interchange -pass-remarks-missed=loop-interchange -stats -S 2>&1 \
4; RUN:     | FileCheck -check-prefix=STATS %s
5; RUN: FileCheck -input-file %t %s
6
7
8; no_deps_interchange just accesses a single nested array and can be interchange.
9; CHECK:      Name:       Interchanged
10; CHECK-NEXT: Function:   no_deps_interchange
11define i32 @no_deps_interchange([1024 x i32]* nocapture %Arr) local_unnamed_addr #0 {
12entry:
13  br label %for1.header
14
15for1.header:                                         ; preds = %entry, %for1.inc
16  %indvars.iv19 = phi i64 [ 0, %entry ], [ %indvars.iv.next20, %for1.inc ]
17  br label %for2
18
19for2:                                        ; preds = %for1.header, %for2
20  %indvars.iv = phi i64 [ 0, %for1.header ], [ %indvars.iv.next, %for2 ]
21  %arrayidx6 = getelementptr inbounds [1024 x i32], [1024 x i32]* %Arr, i64 %indvars.iv, i64 %indvars.iv19
22  store i32 0, i32* %arrayidx6, align 4
23  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
24  %exitcond = icmp ne i64 %indvars.iv.next, 1024
25  br i1 %exitcond, label %for2, label %for1.inc
26
27for1.inc:
28  %indvars.iv.next20 = add nuw nsw i64 %indvars.iv19, 1
29  %exitcond21 = icmp ne i64 %indvars.iv.next20, 1024
30  br i1 %exitcond21, label %for1.header, label %exit
31
32exit:                                 ; preds = %for1.inc
33  ret i32 0
34
35}
36
37; No memory access using any induction variables, interchanging not beneficial.
38; CHECK:      Name:        InterchangeNotProfitable
39; CHECK-NEXT: Function:    no_mem_instrs
40define i32 @no_mem_instrs(i64* %ptr) {
41entry:
42  br label %for1.header
43
44for1.header:                                         ; preds = %entry, %for1.inc
45  %indvars.iv19 = phi i64 [ 0, %entry ], [ %indvars.iv.next20, %for1.inc ]
46  br label %for2
47
48for2:                                        ; preds = %for1.header, %for2
49  %indvars.iv = phi i64 [ 0, %for1.header ], [ %indvars.iv.next, %for2 ]
50  store i64 %indvars.iv, i64* %ptr, align 4
51  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
52  %exitcond = icmp ne i64 %indvars.iv.next, 1024
53  br i1 %exitcond, label %for2, label %for1.inc
54
55for1.inc:
56  %indvars.iv.next20 = add nuw nsw i64 %indvars.iv19, 1
57  %exitcond21 = icmp ne i64 %indvars.iv.next20, 1024
58  br i1 %exitcond21, label %for1.header, label %exit
59
60exit:                                 ; preds = %for1.inc
61  ret i32 0
62}
63
64
65; Check stats, we interchanged 1 out of 3 loops.
66; STATS: 1 loop-interchange - Number of loops interchanged
67