1# RUN: llc -mtriple=thumbv8.1m.main %s -run-pass=arm-low-overhead-loops --verify-machineinstrs -o - | FileCheck %s
2
3# CHECK: while.body:
4# CHECK-NOT: t2DLS
5# CHECK-NOT: t2LEUpdate
6
7--- |
8  target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
9  target triple = "thumbv8.1m.main"
10
11  define i32 @mov_between_dec_end(i32 %n) #0 {
12  entry:
13    %cmp6 = icmp eq i32 %n, 0
14    br i1 %cmp6, label %while.end, label %while.body.preheader
15
16  while.body.preheader:                             ; preds = %entry
17    %start = call i32 @llvm.start.loop.iterations.i32(i32 %n)
18    br label %while.body
19
20  while.body:                                       ; preds = %while.body, %while.body.preheader
21    %0 = phi i32 [ %start, %while.body.preheader ], [ %1, %while.body ]
22    %1 = call i32 @llvm.loop.decrement.reg.i32.i32.i32(i32 %0, i32 1)
23    %add = add i32 %1, 2
24    %2 = icmp ne i32 %1, 0
25    br i1 %2, label %while.body, label %while.end
26
27  while.end:                                        ; preds = %while.body, %entry
28    %res.0.lcssa = phi i32 [ 0, %entry ], [ %add, %while.body ]
29    ret i32 %res.0.lcssa
30  }
31
32  ; Function Attrs: noduplicate nounwind
33  declare i32 @llvm.start.loop.iterations.i32(i32) #1
34
35  ; Function Attrs: noduplicate nounwind
36  declare i32 @llvm.loop.decrement.reg.i32.i32.i32(i32, i32) #1
37
38  ; Function Attrs: nounwind
39  declare void @llvm.stackprotector(i8*, i8**) #2
40
41  attributes #0 = { "target-features"="+mve.fp" }
42  attributes #1 = { noduplicate nounwind }
43  attributes #2 = { nounwind }
44
45...
46---
47name:            mov_between_dec_end
48alignment:       2
49exposesReturnsTwice: false
50legalized:       false
51regBankSelected: false
52selected:        false
53failedISel:      false
54tracksRegLiveness: true
55hasWinCFI:       false
56registers:       []
57liveins:
58  - { reg: '$r0', virtual-reg: '' }
59frameInfo:
60  isFrameAddressTaken: false
61  isReturnAddressTaken: false
62  hasStackMap:     false
63  hasPatchPoint:   false
64  stackSize:       8
65  offsetAdjustment: 0
66  maxAlignment:    4
67  adjustsStack:    false
68  hasCalls:        false
69  stackProtector:  ''
70  maxCallFrameSize: 0
71  cvBytesOfCalleeSavedRegisters: 0
72  hasOpaqueSPAdjustment: false
73  hasVAStart:      false
74  hasMustTailInVarArgFunc: false
75  localFrameSize:  0
76  savePoint:       ''
77  restorePoint:    ''
78fixedStack:      []
79stack:
80  - { id: 0, name: '', type: spill-slot, offset: -4, size: 4, alignment: 4,
81      stack-id: default, callee-saved-register: '$lr', callee-saved-restored: false,
82      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
83  - { id: 1, name: '', type: spill-slot, offset: -8, size: 4, alignment: 4,
84      stack-id: default, callee-saved-register: '$r7', callee-saved-restored: true,
85      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
86callSites:       []
87constants:       []
88machineFunctionInfo: {}
89body:             |
90  bb.0.entry:
91    successors: %bb.4(0x30000000), %bb.1(0x50000000)
92    liveins: $r0, $r7, $lr
93
94    frame-setup tPUSH 14, $noreg, killed $r7, killed $lr, implicit-def $sp, implicit $sp
95    frame-setup CFI_INSTRUCTION def_cfa_offset 8
96    frame-setup CFI_INSTRUCTION offset $lr, -4
97    frame-setup CFI_INSTRUCTION offset $r7, -8
98    tCBZ $r0, %bb.4
99
100  bb.1.while.body.preheader:
101    successors: %bb.2(0x80000000)
102    liveins: $r0
103
104    $lr = tMOVr $r0, 14, $noreg
105    $lr = t2DoLoopStart killed $r0
106
107  bb.2.while.body:
108    successors: %bb.2(0x7c000000), %bb.3(0x04000000)
109    liveins: $lr
110
111    $r4 = tMOVr $lr, 14, $noreg
112    renamable $lr = t2LoopDec killed renamable $lr, 1
113    renamable $r0 = t2ADDri renamable $lr, 2, 14, $noreg, $noreg
114    $lr = tMOVr $r4, 14, $noreg
115    t2LoopEnd renamable $lr, %bb.2, implicit-def dead $cpsr
116    tB %bb.3, 14, $noreg
117
118  bb.3.while.end:
119    liveins: $r0
120
121    tPOP_RET 14, $noreg, def $r7, def $pc, implicit killed $r0
122
123  bb.4:
124    renamable $r0, dead $cpsr = tMOVi8 0, 14, $noreg
125    tPOP_RET 14, $noreg, def $r7, def $pc, implicit killed $r0
126
127...
128