1; RUN: opt -loop-reduce -S < %s | FileCheck %s
2;
3; Test LSR's use of SplitCriticalEdge during phi rewriting.
4
5target triple = "x86-apple-darwin"
6
7; Verify that identical edges are merged. rdar://problem/6453893
8; CHECK-LABEL: @test1(
9; CHECK: bb89:
10; CHECK: phi i8* [ %lsr.iv.next1, %bbA.bb89_crit_edge ], [ %lsr.iv.next1, %bbB.bb89_crit_edge ]{{$}}
11
12define i8* @test1() {
13entry:
14  br label %loop
15
16loop:
17  %rec = phi i32 [ %next, %loop ], [ 0, %entry ]
18  %next = add i32 %rec, 1
19  %tmp75 = getelementptr i8* null, i32 %next
20  br i1 false, label %loop, label %loopexit
21
22loopexit:
23  br i1 false, label %bbA, label %bbB
24
25bbA:
26  switch i32 0, label %bb89 [
27    i32 47, label %bb89
28    i32 58, label %bb89
29  ]
30
31bbB:
32  switch i8 0, label %bb89 [
33    i8 47, label %bb89
34    i8 58, label %bb89
35  ]
36
37bb89:
38  %tmp75phi = phi i8* [ %tmp75, %bbA ], [ %tmp75, %bbA ], [ %tmp75, %bbA ], [ %tmp75, %bbB ], [ %tmp75, %bbB ], [ %tmp75, %bbB ]
39  br label %exit
40
41exit:
42  ret i8* %tmp75phi
43}
44
45; Handle single-predecessor phis: PR13756
46; CHECK-LABEL: @test2(
47; CHECK: bb89:
48; CHECK: phi i8* [ %lsr.iv.next1, %bbA ], [ %lsr.iv.next1, %bbA ], [ %lsr.iv.next1, %bbA ]{{$}}
49define i8* @test2() {
50entry:
51  br label %loop
52
53loop:
54  %rec = phi i32 [ %next, %loop ], [ 0, %entry ]
55  %next = add i32 %rec, 1
56  %tmp75 = getelementptr i8* null, i32 %next
57  br i1 false, label %loop, label %loopexit
58
59loopexit:
60  br i1 false, label %bbA, label %bbB
61
62bbA:
63  switch i32 0, label %bb89 [
64    i32 47, label %bb89
65    i32 58, label %bb89
66  ]
67
68bbB:
69  switch i8 0, label %exit [
70    i8 47, label %exit
71    i8 58, label %exit
72  ]
73
74bb89:
75  %tmp75phi = phi i8* [ %tmp75, %bbA ], [ %tmp75, %bbA ], [ %tmp75, %bbA ]
76  br label %exit
77
78exit:
79  %result = phi i8* [ %tmp75phi, %bb89 ], [ %tmp75, %bbB ], [ %tmp75, %bbB ], [ %tmp75, %bbB ]
80  ret i8* %result
81}
82