1; RUN: opt -loop-reduce -S < %s | FileCheck %s
2;
3; <rdar://10619599> "SelectionDAGBuilder shouldn't visit PHI nodes!" assert.
4; <rdar://10655343> SCEVExpander segfault on simple test case
5
6target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-f128:128:128-n8:16:32"
7target triple = "i386-apple-darwin"
8
9; LSR should convert the inner loop (bb7.us) IV (j.01.us) into float*.
10; This involves a nested AddRec, the outer AddRec's loop invariant components
11; cannot find a preheader, so they should be expanded in the loop header
12; (bb7.lr.ph.us) below the existing phi i.12.us.
13; Currently, LSR won't kick in on such loops.
14; CHECK-LABEL: @nopreheader(
15; CHECK: bb7.us:
16; CHECK-NOT: phi float*
17; CHECK: %j.01.us = phi i32
18; CHECK-NOT: phi float*
19define void @nopreheader(float* nocapture %a, i32 %n) nounwind {
20entry:
21  %0 = sdiv i32 %n, undef
22  indirectbr i8* undef, [label %bb10.preheader]
23
24bb10.preheader:                                   ; preds = %bb4
25  indirectbr i8* undef, [label %bb8.preheader.lr.ph, label %return]
26
27bb8.preheader.lr.ph:                              ; preds = %bb10.preheader
28  indirectbr i8* null, [label %bb7.lr.ph.us, label %bb9]
29
30bb7.lr.ph.us:                                     ; preds = %bb9.us, %bb8.preheader.lr.ph
31  %i.12.us = phi i32 [ %2, %bb9.us ], [ 0, %bb8.preheader.lr.ph ]
32  %tmp30 = mul i32 %0, %i.12.us
33  indirectbr i8* undef, [label %bb7.us]
34
35bb7.us:                                           ; preds = %bb7.lr.ph.us, %bb7.us
36  %j.01.us = phi i32 [ 0, %bb7.lr.ph.us ], [ %1, %bb7.us ]
37  %tmp31 = add i32 %tmp30, %j.01.us
38  %scevgep9 = getelementptr float* %a, i32 %tmp31
39  store float undef, float* %scevgep9, align 1
40  %1 = add nsw i32 %j.01.us, 1
41  indirectbr i8* undef, [label %bb9.us, label %bb7.us]
42
43bb9.us:                                           ; preds = %bb7.us
44  %2 = add nsw i32 %i.12.us, 1
45  indirectbr i8* undef, [label %bb7.lr.ph.us, label %return]
46
47bb9:                                              ; preds = %bb9, %bb8.preheader.lr.ph
48  indirectbr i8* undef, [label %bb9, label %return]
49
50return:                                           ; preds = %bb9, %bb9.us, %bb10.preheader
51  ret void
52}
53
54; In this case, SCEVExpander simply cannot materialize the AddRecExpr
55; that LSR picks. We must detect that %bb8.preheader does not have a
56; preheader and avoid performing LSR on %bb7.
57; CHECK-LABEL: @nopreheader2(
58; CHECK: bb7:
59; CHECK: %indvar = phi i32
60define fastcc void @nopreheader2([200 x i32]* nocapture %Array2) nounwind {
61entry:
62  indirectbr i8* undef, [label %bb]
63
64bb:                                               ; preds = %bb, %entry
65  indirectbr i8* undef, [label %bb3, label %bb]
66
67bb3:                                              ; preds = %bb3, %bb
68  indirectbr i8* undef, [label %bb8.preheader, label %bb3]
69
70bb8.preheader:                                    ; preds = %bb9, %bb3
71  %indvar5 = phi i32 [ %indvar.next6, %bb9 ], [ 0, %bb3 ]
72  %tmp26 = add i32 %indvar5, 13
73  indirectbr i8* null, [label %bb7]
74
75bb7:                                              ; preds = %bb8.preheader, %bb7
76  %indvar = phi i32 [ 0, %bb8.preheader ], [ %indvar.next, %bb7 ]
77  %scevgep = getelementptr [200 x i32]* %Array2, i32 %tmp26, i32 %indvar
78  store i32 undef, i32* %scevgep, align 4
79  %indvar.next = add i32 %indvar, 1
80  indirectbr i8* undef, [label %bb9, label %bb7]
81
82bb9:                                              ; preds = %bb7
83  %indvar.next6 = add i32 %indvar5, 1
84  indirectbr i8* undef, [label %return, label %bb8.preheader]
85
86return:                                           ; preds = %bb9
87  ret void
88}
89