1; RUN: llc -regalloc=greedy < %s | FileCheck %s
2
3; LSR shouldn't introduce more induction variables than needed, increasing
4; register pressure and therefore spilling. There is more room for improvement
5; here.
6
7; CHECK: sub sp, #{{40|32|28|24}}
8
9; CHECK: %for.inc
10; CHECK-NOT: ldr
11; CHECK: add
12
13target datalayout = "e-p:32:32:32-i1:8:32-i8:8:32-i16:16:32-i32:32:32-i64:32:32-f32:32:32-f64:32:32-v64:32:64-v128:32:128-a0:0:32-n32"
14target triple = "thumbv7-apple-ios"
15
16%struct.partition_entry = type { i32, i32, i64, i64 }
17
18define i32 @partition_overlap_check(%struct.partition_entry* nocapture %part, i32 %num_entries) nounwind readonly optsize ssp {
19entry:
20  %cmp79 = icmp sgt i32 %num_entries, 0
21  br i1 %cmp79, label %outer.loop, label %for.end72
22
23outer.loop:                                 ; preds = %for.inc69, %entry
24  %overlap.081 = phi i32 [ %overlap.4, %for.inc69 ], [ 0, %entry ]
25  %0 = phi i32 [ %inc71, %for.inc69 ], [ 0, %entry ]
26  %offset = getelementptr %struct.partition_entry* %part, i32 %0, i32 2
27  %len = getelementptr %struct.partition_entry* %part, i32 %0, i32 3
28  %tmp5 = load i64* %offset, align 4
29  %tmp15 = load i64* %len, align 4
30  %add = add nsw i64 %tmp15, %tmp5
31  br label %inner.loop
32
33inner.loop:                                       ; preds = %for.inc, %outer.loop
34  %overlap.178 = phi i32 [ %overlap.081, %outer.loop ], [ %overlap.4, %for.inc ]
35  %1 = phi i32 [ 0, %outer.loop ], [ %inc, %for.inc ]
36  %cmp23 = icmp eq i32 %0, %1
37  br i1 %cmp23, label %for.inc, label %if.end
38
39if.end:                                           ; preds = %inner.loop
40  %len39 = getelementptr %struct.partition_entry* %part, i32 %1, i32 3
41  %offset28 = getelementptr %struct.partition_entry* %part, i32 %1, i32 2
42  %tmp29 = load i64* %offset28, align 4
43  %tmp40 = load i64* %len39, align 4
44  %add41 = add nsw i64 %tmp40, %tmp29
45  %cmp44 = icmp sge i64 %tmp29, %tmp5
46  %cmp47 = icmp slt i64 %tmp29, %add
47  %or.cond = and i1 %cmp44, %cmp47
48  %overlap.2 = select i1 %or.cond, i32 1, i32 %overlap.178
49  %cmp52 = icmp sle i64 %add41, %add
50  %cmp56 = icmp sgt i64 %add41, %tmp5
51  %or.cond74 = and i1 %cmp52, %cmp56
52  %overlap.3 = select i1 %or.cond74, i32 1, i32 %overlap.2
53  %cmp61 = icmp sgt i64 %tmp29, %tmp5
54  %cmp65 = icmp slt i64 %add41, %add
55  %or.cond75 = or i1 %cmp61, %cmp65
56  br i1 %or.cond75, label %for.inc, label %if.then66
57
58if.then66:                                        ; preds = %if.end
59  br label %for.inc
60
61for.inc:                                          ; preds = %if.end, %if.then66, %inner.loop
62  %overlap.4 = phi i32 [ %overlap.178, %inner.loop ], [ 1, %if.then66 ], [ %overlap.3, %if.end ]
63  %inc = add nsw i32 %1, 1
64  %exitcond = icmp eq i32 %inc, %num_entries
65  br i1 %exitcond, label %for.inc69, label %inner.loop
66
67for.inc69:                                        ; preds = %for.inc
68  %inc71 = add nsw i32 %0, 1
69  %exitcond83 = icmp eq i32 %inc71, %num_entries
70  br i1 %exitcond83, label %for.end72, label %outer.loop
71
72for.end72:                                        ; preds = %for.inc69, %entry
73  %overlap.0.lcssa = phi i32 [ 0, %entry ], [ %overlap.4, %for.inc69 ]
74  ret i32 %overlap.0.lcssa
75}
76