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, 0
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  declare i32 @llvm.start.loop.iterations.i32(i32) #1
33  declare i32 @llvm.loop.decrement.reg.i32.i32.i32(i32, i32) #1
34
35  attributes #0 = { "target-features"="+mve.fp" }
36  attributes #1 = { noduplicate nounwind }
37  attributes #2 = { nounwind }
38
39...
40---
41name:            mov_between_dec_end
42alignment:       2
43exposesReturnsTwice: false
44legalized:       false
45regBankSelected: false
46selected:        false
47failedISel:      false
48tracksRegLiveness: true
49hasWinCFI:       false
50registers:       []
51liveins:
52  - { reg: '$r0', virtual-reg: '' }
53frameInfo:
54  isFrameAddressTaken: false
55  isReturnAddressTaken: false
56  hasStackMap:     false
57  hasPatchPoint:   false
58  stackSize:       8
59  offsetAdjustment: 0
60  maxAlignment:    4
61  adjustsStack:    false
62  hasCalls:        false
63  stackProtector:  ''
64  maxCallFrameSize: 0
65  cvBytesOfCalleeSavedRegisters: 0
66  hasOpaqueSPAdjustment: false
67  hasVAStart:      false
68  hasMustTailInVarArgFunc: false
69  localFrameSize:  0
70  savePoint:       ''
71  restorePoint:    ''
72fixedStack:      []
73stack:
74  - { id: 0, name: '', type: spill-slot, offset: -4, size: 4, alignment: 4,
75      stack-id: default, callee-saved-register: '$lr', callee-saved-restored: false,
76      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
77  - { id: 1, name: '', type: spill-slot, offset: -8, size: 4, alignment: 4,
78      stack-id: default, callee-saved-register: '$r7', callee-saved-restored: true,
79      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
80callSites:       []
81constants:       []
82machineFunctionInfo: {}
83body:             |
84  bb.0.entry:
85    successors: %bb.4(0x30000000), %bb.1(0x50000000)
86    liveins: $r0, $r7, $lr
87
88    frame-setup tPUSH 14, $noreg, killed $r7, killed $lr, implicit-def $sp, implicit $sp
89    frame-setup CFI_INSTRUCTION def_cfa_offset 8
90    frame-setup CFI_INSTRUCTION offset $lr, -4
91    frame-setup CFI_INSTRUCTION offset $r7, -8
92    tCBZ $r0, %bb.4
93
94  bb.1.while.body.preheader:
95    successors: %bb.2(0x80000000)
96    liveins: $r0
97
98    $lr = tMOVr $r0, 14, $noreg
99    $lr = t2DoLoopStart killed $r0
100
101  bb.2.while.body:
102    successors: %bb.2(0x7c000000), %bb.3(0x04000000)
103    liveins: $lr, $r4
104
105    renamable $r4 = nsw tADDhirr killed renamable $r4, killed renamable $r4, 14, $noreg
106    renamable $lr = t2LoopDec killed renamable $lr, 1
107    renamable $r4 = tMOVr $lr, 14, $noreg
108    t2LoopEnd renamable $lr, %bb.2, implicit-def dead $cpsr
109    tB %bb.3, 14, $noreg
110
111  bb.3.while.end:
112    liveins: $lr
113
114    $r0 = tMOVr killed $lr, 14, $noreg
115    tPOP_RET 14, $noreg, def $r7, def $pc, implicit killed $r0
116
117  bb.4:
118    renamable $lr = t2MOVi 0, 14, $noreg, $noreg
119    $r0 = tMOVr killed $lr, 14, $noreg
120    tPOP_RET 14, $noreg, def $r7, def $pc, implicit killed $r0
121
122...
123