xref: /llvm-project/llvm/test/Transforms/LCSSA/unreachable-use.ll (revision 8205a68da89123bd29ea253f9c76d440f3afb987)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt < %s -passes=lcssa -S -verify-loop-info | FileCheck %s
3
4; LCSSA doesn't need to transform uses in blocks not reachable
5; from the entry block.
6
7; PR6546
8define void @test_pr6546(ptr %src, i1 %c) {
9; CHECK-LABEL: @test_pr6546(
10; CHECK-NEXT:  bb:
11; CHECK-NEXT:    br label [[BB44:%.*]]
12; CHECK:       bb44:
13; CHECK-NEXT:    br i1 [[C:%.*]], label [[BB7:%.*]], label [[BB45:%.*]]
14; CHECK:       bb7:
15; CHECK-NEXT:    [[TMP:%.*]] = getelementptr ptr, ptr [[SRC:%.*]], i64 3
16; CHECK-NEXT:    br label [[BB15:%.*]]
17; CHECK:       bb15:
18; CHECK-NEXT:    br label [[BB44]]
19; CHECK:       bb32:
20; CHECK-NEXT:    [[TMP33:%.*]] = load ptr, ptr [[TMP]], align 8
21; CHECK-NEXT:    br label [[BB45]]
22; CHECK:       bb45:
23; CHECK-NEXT:    unreachable
24;
25bb:
26  br label %bb44
27
28bb44:
29  br i1 %c, label %bb7, label %bb45
30
31bb7:
32  %tmp = getelementptr ptr, ptr %src, i64 3
33  br label %bb15
34
35bb15:
36  br label %bb44
37
38bb32:
39  %tmp33 = load ptr, ptr %tmp, align 8
40  br label %bb45
41
42bb45:
43  unreachable
44}
45
46define void @multiple_unreachable_uses(ptr %A, ptr %B) {
47entry:
48  br label %loop
49
50loop:
51  %gep.A = getelementptr inbounds float, ptr %A, i64 10
52  %gep.B = getelementptr inbounds ptr, ptr %B, i64 20
53  br i1 false, label %exit, label %loop
54
55dead:                 ; No predecessors!
56  %l1 = load float, ptr %gep.A, align 4
57  %l2 = load ptr, ptr %gep.B, align 8
58  br label %exit
59
60exit:
61  ret void
62}
63