xref: /llvm-project/llvm/test/Transforms/SimpleLoopUnswitch/pr58868-scev-invalidation-for-phis.ll (revision 7854a1abfd9a52dec0fe5d668e26de19614faefb)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt -passes="loop-mssa(loop-deletion,simple-loop-unswitch<nontrivial;trivial>),loop(indvars)" -verify-scev -S %s | FileCheck %s
3
4define void @pr58868(i1 %c.1, ptr %src, ptr %dst) {
5; CHECK-LABEL: @pr58868(
6; CHECK-NEXT:  entry:
7; CHECK-NEXT:    br i1 [[C_1:%.*]], label [[ENTRY_SPLIT_US:%.*]], label [[ENTRY_SPLIT:%.*]]
8; CHECK:       entry.split.us:
9; CHECK-NEXT:    br label [[OUTER_HEADER_US:%.*]]
10; CHECK:       outer.header.us:
11; CHECK-NEXT:    br label [[OUTER_BB1_US:%.*]]
12; CHECK:       outer.bb1.us:
13; CHECK-NEXT:    br label [[OUTER_BB2_US:%.*]]
14; CHECK:       outer.bb2.us:
15; CHECK-NEXT:    [[LV_US:%.*]] = load i16, ptr [[SRC:%.*]], align 1
16; CHECK-NEXT:    br i1 true, label [[OUTER_HEADER_LOOPEXIT_US:%.*]], label [[OUTER_BB2_SPLIT_SPLIT_US:%.*]]
17; CHECK:       outer.header.loopexit.us:
18; CHECK-NEXT:    br label [[OUTER_HEADER_US]]
19; CHECK:       outer.bb2.split.split.us:
20; CHECK-NEXT:    [[LV_LCSSA_US:%.*]] = phi i16 [ [[LV_US]], [[OUTER_BB2_US]] ]
21; CHECK-NEXT:    br label [[OUTER_BB2_SPLIT:%.*]]
22; CHECK:       entry.split:
23; CHECK-NEXT:    br label [[OUTER_HEADER:%.*]]
24; CHECK:       outer.header.loopexit:
25; CHECK-NEXT:    unreachable
26; CHECK:       outer.header:
27; CHECK-NEXT:    br label [[OUTER_BB2:%.*]]
28; CHECK:       outer.bb2:
29; CHECK-NEXT:    [[LV:%.*]] = load i16, ptr [[SRC]], align 1
30; CHECK-NEXT:    br i1 false, label [[OUTER_HEADER_LOOPEXIT:%.*]], label [[OUTER_BB2_SPLIT_SPLIT:%.*]]
31; CHECK:       outer.bb2.split.split:
32; CHECK-NEXT:    [[LV_LCSSA:%.*]] = phi i16 [ [[LV]], [[OUTER_BB2]] ]
33; CHECK-NEXT:    br label [[OUTER_BB2_SPLIT]]
34; CHECK:       outer.bb2.split:
35; CHECK-NEXT:    [[DOTUS_PHI:%.*]] = phi i16 [ [[LV_LCSSA]], [[OUTER_BB2_SPLIT_SPLIT]] ], [ [[LV_LCSSA_US]], [[OUTER_BB2_SPLIT_SPLIT_US]] ]
36; CHECK-NEXT:    br label [[INNER_HEADER:%.*]]
37; CHECK:       inner.header:
38; CHECK-NEXT:    [[IV:%.*]] = phi i16 [ [[DOTUS_PHI]], [[OUTER_BB2_SPLIT]] ], [ [[IV_NEXT:%.*]], [[INNER_LATCH:%.*]] ]
39; CHECK-NEXT:    br label [[INNER_LATCH]]
40; CHECK:       inner.latch:
41; CHECK-NEXT:    [[IV_NEXT]] = add nsw i16 [[IV]], 1
42; CHECK-NEXT:    store i16 0, ptr [[DST:%.*]], align 1
43; CHECK-NEXT:    [[C_2:%.*]] = icmp ne i16 [[IV]], 0
44; CHECK-NEXT:    br i1 [[C_2]], label [[INNER_HEADER]], label [[EXIT:%.*]]
45; CHECK:       exit:
46; CHECK-NEXT:    ret void
47;
48entry:
49  br label %outer.header
50
51outer.header:
52  br i1 %c.1, label %outer.bb1, label %outer.bb2
53
54outer.bb1:
55  br label %outer.bb2
56
57outer.bb2:
58  %lv = load i16, ptr %src, align 1
59  br label %inner.header
60
61inner.header:
62  %iv = phi i16 [ %lv, %outer.bb2 ], [ %iv.next, %inner.latch ]
63  br i1 %c.1, label %outer.header, label %inner.latch
64
65inner.latch:
66  %iv.next = add nsw i16 %iv, 1
67  store i16 0, ptr %dst, align 1
68  %c.2 = icmp ne i16 %iv, 0
69  br i1 %c.2, label %inner.header, label %exit
70
71exit:
72  ret void
73}
74