xref: /llvm-project/llvm/test/Transforms/GVN/PRE/load-pre-across-backedge.ll (revision 0676acb6fd8d5e22fde16e6ec977ceac08427ab0)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt -passes=gvn -S < %s | FileCheck %s
3
4; Check that PRE-LOAD across backedge does not
5; result in invalid dominator tree.
6declare void @use(i32)
7
8define void @test1(i1 %c, i32 %arg) {
9; CHECK-LABEL: @test1(
10; CHECK-NEXT:    br i1 [[C:%.*]], label [[BB1:%.*]], label [[DOTBB2_CRIT_EDGE:%.*]]
11; CHECK:       .bb2_crit_edge:
12; CHECK-NEXT:    [[DOTPRE:%.*]] = shl i32 [[ARG:%.*]], 2
13; CHECK-NEXT:    br label [[BB2:%.*]]
14; CHECK:       bb1:
15; CHECK-NEXT:    [[SHL1:%.*]] = shl i32 [[ARG]], 2
16; CHECK-NEXT:    br label [[BB3:%.*]]
17; CHECK:       bb2:
18; CHECK-NEXT:    [[SHL2_PRE_PHI:%.*]] = phi i32 [ [[DOTPRE]], [[DOTBB2_CRIT_EDGE]] ], [ [[SHL3:%.*]], [[BB3]] ]
19; CHECK-NEXT:    call void @use(i32 [[SHL2_PRE_PHI]])
20; CHECK-NEXT:    br label [[BB3]]
21; CHECK:       bb3:
22; CHECK-NEXT:    [[SHL3]] = shl i32 [[ARG]], 2
23; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i32, ptr null, i32 [[SHL3]]
24; CHECK-NEXT:    [[V:%.*]] = load i32, ptr [[GEP]], align 4
25; CHECK-NEXT:    call void @use(i32 [[V]])
26; CHECK-NEXT:    br label [[BB2]]
27;
28  br i1 %c, label %bb1, label %bb2
29
30bb1:
31  %shl1 = shl i32 %arg, 2
32  br label %bb3
33
34bb2:
35  %shl2 = shl i32 %arg, 2
36  call void @use(i32 %shl2)
37  br label %bb3
38
39bb3:
40  %shl3 = shl i32 %arg, 2
41  %gep = getelementptr i32, ptr null, i32 %shl3
42  %v = load i32, ptr %gep, align 4
43  call void @use(i32 %v)
44  br label %bb2
45}
46