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