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1; RUN: opt -S -gvn-hoist < %s | FileCheck %s
2
3; Checking gvn-hoist in case of infinite loops and irreducible control flow.
4
5; Check that bitcast is not hoisted beacuse down safety is not guaranteed.
6; CHECK-LABEL: @bazv1
7; CHECK: if.then.i:
8; CHECK: bitcast
9; CHECK-NEXT: load
10; CHECK: if.then4.i:
11; CHECK: bitcast
12; CHECK-NEXT: load
13
14%class.bar = type { i8*, %class.base* }
15%class.base = type { i32 (...)** }
16
17; Function Attrs: noreturn nounwind uwtable
18define void @bazv1() local_unnamed_addr {
19entry:
20  %agg.tmp = alloca %class.bar, align 8
21  %x.sroa.2.0..sroa_idx2 = getelementptr inbounds %class.bar, %class.bar* %agg.tmp, i64 0, i32 1
22  store %class.base* null, %class.base** %x.sroa.2.0..sroa_idx2, align 8
23  call void @_Z3foo3bar(%class.bar* nonnull %agg.tmp)
24  %0 = load %class.base*, %class.base** %x.sroa.2.0..sroa_idx2, align 8
25  %1 = bitcast %class.bar* %agg.tmp to %class.base*
26  %cmp.i = icmp eq %class.base* %0, %1
27  br i1 %cmp.i, label %if.then.i, label %if.else.i
28
29if.then.i:                                        ; preds = %entry
30  %2 = bitcast %class.base* %0 to void (%class.base*)***
31  %vtable.i = load void (%class.base*)**, void (%class.base*)*** %2, align 8
32  %vfn.i = getelementptr inbounds void (%class.base*)*, void (%class.base*)** %vtable.i, i64 2
33  %3 = load void (%class.base*)*, void (%class.base*)** %vfn.i, align 8
34  call void %3(%class.base* %0)
35  br label %while.cond.preheader
36
37if.else.i:                                        ; preds = %entry
38  %tobool.i = icmp eq %class.base* %0, null
39  br i1 %tobool.i, label %while.cond.preheader, label %if.then4.i
40
41if.then4.i:                                       ; preds = %if.else.i
42  %4 = bitcast %class.base* %0 to void (%class.base*)***
43  %vtable6.i = load void (%class.base*)**, void (%class.base*)*** %4, align 8
44  %vfn7.i = getelementptr inbounds void (%class.base*)*, void (%class.base*)** %vtable6.i, i64 3
45  %5 = load void (%class.base*)*, void (%class.base*)** %vfn7.i, align 8
46  call void %5(%class.base* nonnull %0)
47  br label %while.cond.preheader
48
49while.cond.preheader:                             ; preds = %if.then.i, %if.else.i, %if.then4.i
50  br label %while.cond
51
52while.cond:                                       ; preds = %while.cond.preheader, %while.cond
53  %call = call i32 @sleep(i32 10)
54  br label %while.cond
55}
56
57declare void @_Z3foo3bar(%class.bar*) local_unnamed_addr
58
59declare i32 @sleep(i32) local_unnamed_addr
60
61; Check that the load is hoisted even if it is inside an irreducible control flow
62; because the load is anticipable on all paths.
63
64; CHECK-LABEL: @bazv
65; CHECK: bb2:
66; CHECK-NOT: load
67; CHECK-NOT: bitcast
68
69define void @bazv() {
70entry:
71  %agg.tmp = alloca %class.bar, align 8
72  %x= getelementptr inbounds %class.bar, %class.bar* %agg.tmp, i64 0, i32 1
73  %0 = load %class.base*, %class.base** %x, align 8
74  %1 = bitcast %class.bar* %agg.tmp to %class.base*
75  %cmp.i = icmp eq %class.base* %0, %1
76  br i1 %cmp.i, label %bb1, label %bb4
77
78bb1:
79  %b1 = bitcast %class.base* %0 to void (%class.base*)***
80  %i = load void (%class.base*)**, void (%class.base*)*** %b1, align 8
81  %vfn.i = getelementptr inbounds void (%class.base*)*, void (%class.base*)** %i, i64 2
82  %cmp.j = icmp eq %class.base* %0, %1
83  br i1 %cmp.j, label %bb2, label %bb3
84
85bb2:
86  %l1 = load void (%class.base*)*, void (%class.base*)** %vfn.i, align 8
87  br label %bb3
88
89bb3:
90  %l2 = load void (%class.base*)*, void (%class.base*)** %vfn.i, align 8
91  br label %bb2
92
93bb4:
94  %b2 = bitcast %class.base* %0 to void (%class.base*)***
95  ret void
96}
97