1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
|
; RUN: llc < %s -mtriple=armv7-apple-darwin | FileCheck %s
; PHI elimination shouldn't break backedge.
; rdar://8263994
%struct.list_data_s = type { i16, i16 }
%struct.list_head = type { %struct.list_head*, %struct.list_data_s* }
define arm_apcscc %struct.list_head* @t1(%struct.list_head* %list) nounwind {
entry:
; CHECK: t1:
%0 = icmp eq %struct.list_head* %list, null
br i1 %0, label %bb2, label %bb
bb:
; CHECK: LBB0_1:
; CHECK: bne LBB0_1
; CHECK-NOT: b LBB0_1
; CHECK: bx lr
%list_addr.05 = phi %struct.list_head* [ %2, %bb ], [ %list, %entry ]
%next.04 = phi %struct.list_head* [ %list_addr.05, %bb ], [ null, %entry ]
%1 = getelementptr inbounds %struct.list_head* %list_addr.05, i32 0, i32 0
%2 = load %struct.list_head** %1, align 4
store %struct.list_head* %next.04, %struct.list_head** %1, align 4
%3 = icmp eq %struct.list_head* %2, null
br i1 %3, label %bb2, label %bb
bb2:
%next.0.lcssa = phi %struct.list_head* [ null, %entry ], [ %list_addr.05, %bb ]
ret %struct.list_head* %next.0.lcssa
}
; Optimize loop entry, eliminate intra loop branches
; rdar://8117827
define i32 @t2(i32 %passes, i32* nocapture %src, i32 %size) nounwind readonly {
entry:
; CHECK: t2:
; CHECK: beq LBB1_[[RET:.]]
%0 = icmp eq i32 %passes, 0 ; <i1> [#uses=1]
br i1 %0, label %bb5, label %bb.nph15
; CHECK: LBB1_[[PREHDR:.]]: @ %bb2.preheader
bb1: ; preds = %bb2.preheader, %bb1
; CHECK: LBB1_[[BB1:.]]: @ %bb1
; CHECK: bne LBB1_[[BB1]]
%indvar = phi i32 [ %indvar.next, %bb1 ], [ 0, %bb2.preheader ] ; <i32> [#uses=2]
%sum.08 = phi i32 [ %2, %bb1 ], [ %sum.110, %bb2.preheader ] ; <i32> [#uses=1]
%tmp17 = sub i32 %i.07, %indvar ; <i32> [#uses=1]
%scevgep = getelementptr i32* %src, i32 %tmp17 ; <i32*> [#uses=1]
%1 = load i32* %scevgep, align 4 ; <i32> [#uses=1]
%2 = add nsw i32 %1, %sum.08 ; <i32> [#uses=2]
%indvar.next = add i32 %indvar, 1 ; <i32> [#uses=2]
%exitcond = icmp eq i32 %indvar.next, %size ; <i1> [#uses=1]
br i1 %exitcond, label %bb3, label %bb1
bb3: ; preds = %bb1, %bb2.preheader
; CHECK: LBB1_[[BB3:.]]: @ %bb3
; CHECK: bne LBB1_[[PREHDR]]
; CHECK-NOT: b LBB1_
%sum.0.lcssa = phi i32 [ %sum.110, %bb2.preheader ], [ %2, %bb1 ] ; <i32> [#uses=2]
%3 = add i32 %pass.011, 1 ; <i32> [#uses=2]
%exitcond18 = icmp eq i32 %3, %passes ; <i1> [#uses=1]
br i1 %exitcond18, label %bb5, label %bb2.preheader
bb.nph15: ; preds = %entry
%i.07 = add i32 %size, -1 ; <i32> [#uses=2]
%4 = icmp sgt i32 %i.07, -1 ; <i1> [#uses=1]
br label %bb2.preheader
bb2.preheader: ; preds = %bb3, %bb.nph15
%pass.011 = phi i32 [ 0, %bb.nph15 ], [ %3, %bb3 ] ; <i32> [#uses=1]
%sum.110 = phi i32 [ 0, %bb.nph15 ], [ %sum.0.lcssa, %bb3 ] ; <i32> [#uses=2]
br i1 %4, label %bb1, label %bb3
; CHECK: LBB1_[[RET]]: @ %bb5
; CHECK: pop
bb5: ; preds = %bb3, %entry
%sum.1.lcssa = phi i32 [ 0, %entry ], [ %sum.0.lcssa, %bb3 ] ; <i32> [#uses=1]
ret i32 %sum.1.lcssa
}
|