llvm-project

1
; Test that LICM correctly detects conflicting accesses to memory in deeply
2
; nested subloops. This works in the legacy PM due to a special retained map of
3
; alias information for inner loops, and in the new PM it is recomputed for each
4
; loop.
5
;
6
; RUN: opt -S -aa-pipeline=basic-aa -passes='require<opt-remark-emit>,loop-mssa(licm)' < %s | FileCheck %s
7
; RUN: opt -S -passes=licm < %s | FileCheck %s
8

9
define i32 @test(ptr %a, i64 %n.0, i64 %n.0.0, i64 %n.0.0.0, i64 %n.0.0.0.0) nounwind uwtable readonly {
10
; CHECK-LABEL: define i32 @test
11
entry:
12
  %b = alloca i32
13
  %c = alloca i32
14
  br label %l.0.header
15
; CHECK: %b = alloca i32
16
; CHECK: %c = alloca i32
17
; CHECK-NOT: load
18
; CHECK: br
19

20
l.0.header:
21
  %iv.0 = phi i64 [ %iv.0.next, %l.0.latch ], [ 0, %entry ]
22
  %iv.0.next = add i64 %iv.0, 1
23
  %exitcond.0 = icmp eq i64 %iv.0.next, %n.0
24
  %a.val = load i32, ptr %a
25
  store i32 %a.val, ptr %b
26
  %c.val = trunc i64 %iv.0 to i32
27
  store i32 %c.val, ptr %c
28
  br label %l.0.0.header
29
; CHECK: %[[AV:.*]] = load i32, ptr %a
30
; CHECK: store i32 %[[AV]], ptr %b
31
; CHECK: %[[CT:.*]] = trunc i64 {{.*}} to i32
32
; CHECK: store i32 %[[CT]], ptr %c
33
; CHECK: br
34

35
l.0.0.header:
36
  %iv.0.0 = phi i64 [ %iv.0.0.next, %l.0.0.latch ], [ 0, %l.0.header ]
37
  %iv.0.0.next = add i64 %iv.0.0, 1
38
  %exitcond.0.0 = icmp eq i64 %iv.0.0.next, %n.0.0
39
  br label %l.0.0.0.header
40
; CHECK: br
41

42
l.0.0.0.header:
43
  %iv.0.0.0 = phi i64 [ %iv.0.0.0.next, %l.0.0.0.header ], [ 0, %l.0.0.header ]
44
  %iv.0.0.0.next = add i64 %iv.0.0.0, 1
45
  %exitcond.0.0.0 = icmp eq i64 %iv.0.0.0.next, %n.0.0.0
46
  call void @llvm.memcpy.p0.p0.i64(ptr %a, ptr %c, i64 4, i1 false)
47
  call void @llvm.memcpy.p0.p0.i64(ptr %b, ptr %c, i64 4, i1 false)
48
  br i1 %exitcond.0.0.0, label %l.0.0.0.header, label %l.0.0.latch
49
; CHECK: call void @llvm.memcpy.{{.*}}(ptr %a, ptr %c, i64 4
50
; CHECK: call void @llvm.memcpy.{{.*}}(ptr %b, ptr %c, i64 4
51
; CHECK: br
52

53
l.0.0.latch:
54
  br i1 %exitcond.0.0, label %l.0.0.header, label %l.0.latch
55
; CHECK: br
56

57
l.0.latch:
58
  %b.val = load i32, ptr %b
59
  br i1 %exitcond.0, label %exit, label %l.0.header
60
; CHECK: %[[BV:.*]] = load i32, ptr %b
61
; CHECK: br
62

63
exit:
64
  %result.lcssa = phi i32 [ %b.val, %l.0.latch ]
65
  ret i32 %b.val
66
; CHECK: %[[LCSSA:.*]] = phi i32 [ %[[BV]], %{{.*}} ]
67
; CHECK: ret i32 %[[LCSSA]]
68
}
69

70
declare void @llvm.memcpy.p0.p0.i64(ptr nocapture writeonly, ptr nocapture readonly, i64, i1)
71