xref: /llvm-project/llvm/test/Transforms/InstCombine/dont-distribute-phi.ll (revision e44b11d9b6baa0bfc3d864d455a4b5717499f05b)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt < %s -passes=instcombine -S | FileCheck %s
3;
4; This test ensures that InstCombine does not distribute And over Xor
5; using simplifications involving undef.
6
7define zeroext i1 @foo(i32 %arg) {
8; CHECK-LABEL: @foo(
9; CHECK-NEXT:  entry:
10; CHECK-NEXT:    [[CMP1:%.*]] = icmp ne i32 [[ARG:%.*]], 37
11; CHECK-NEXT:    br i1 [[CMP1]], label [[BB_ELSE:%.*]], label [[BB_THEN:%.*]]
12; CHECK:       bb_then:
13; CHECK-NEXT:    call void @bar()
14; CHECK-NEXT:    br label [[BB_EXIT:%.*]]
15; CHECK:       bb_else:
16; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i32 [[ARG]], 17
17; CHECK-NEXT:    br label [[BB_EXIT]]
18; CHECK:       bb_exit:
19; CHECK-NEXT:    [[PHI1:%.*]] = phi i1 [ [[CMP2]], [[BB_ELSE]] ], [ undef, [[BB_THEN]] ]
20; CHECK-NEXT:    [[AND1:%.*]] = and i1 [[PHI1]], [[CMP1]]
21; CHECK-NEXT:    ret i1 [[AND1]]
22;
23
24entry:
25  %cmp1 = icmp eq i32 %arg, 37
26  br i1 %cmp1, label %bb_then, label %bb_else
27
28bb_then:
29  call void @bar()
30  br label %bb_exit
31
32bb_else:
33  %cmp2 = icmp slt i32 %arg, 17
34  br label %bb_exit
35
36bb_exit:
37  %phi1 = phi i1 [ %cmp2, %bb_else ], [ undef, %bb_then ]
38  %xor1 = xor i1 %cmp1, true
39  %and1 = and i1 %phi1, %xor1
40  ret i1 %and1
41}
42
43define zeroext i1 @foo_logical(i32 %arg) {
44; CHECK-LABEL: @foo_logical(
45; CHECK-NEXT:  entry:
46; CHECK-NEXT:    [[CMP1:%.*]] = icmp ne i32 [[ARG:%.*]], 37
47; CHECK-NEXT:    br i1 [[CMP1]], label [[BB_ELSE:%.*]], label [[BB_THEN:%.*]]
48; CHECK:       bb_then:
49; CHECK-NEXT:    call void @bar()
50; CHECK-NEXT:    br label [[BB_EXIT:%.*]]
51; CHECK:       bb_else:
52; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i32 [[ARG]], 17
53; CHECK-NEXT:    br label [[BB_EXIT]]
54; CHECK:       bb_exit:
55; CHECK-NEXT:    [[PHI1:%.*]] = phi i1 [ [[CMP2]], [[BB_ELSE]] ], [ undef, [[BB_THEN]] ]
56; CHECK-NEXT:    [[AND1:%.*]] = and i1 [[PHI1]], [[CMP1]]
57; CHECK-NEXT:    ret i1 [[AND1]]
58;
59
60entry:
61  %cmp1 = icmp eq i32 %arg, 37
62  br i1 %cmp1, label %bb_then, label %bb_else
63
64bb_then:
65  call void @bar()
66  br label %bb_exit
67
68bb_else:
69  %cmp2 = icmp slt i32 %arg, 17
70  br label %bb_exit
71
72bb_exit:
73  %phi1 = phi i1 [ %cmp2, %bb_else ], [ undef, %bb_then ]
74  %xor1 = xor i1 %cmp1, true
75  %and1 = select i1 %phi1, i1 %xor1, i1 false
76  ret i1 %and1
77}
78
79declare void @bar()
80