# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: llc -mtriple=thumbv8.1m.main -run-pass=arm-low-overhead-loops -verify-machineinstrs %s -o - | FileCheck %s
# Check that subs isn't used during the revert because there's a def after LoopDec.
--- |
define i32 @do_copy(i32 %n, ptr nocapture %p, ptr nocapture readonly %q) {
entry:
%scevgep = getelementptr i32, ptr %q, i32 -1
%scevgep3 = getelementptr i32, ptr %p, i32 -1
%start = call i32 @llvm.start.loop.iterations.i32(i32 %n)
%limit = lshr i32 %n, 1
br label %while.body
while.body: ; preds = %while.body, %entry
%lsr.iv4 = phi ptr [ %scevgep5, %while.body ], [ %scevgep3, %entry ]
%lsr.iv = phi ptr [ %scevgep1, %while.body ], [ %scevgep, %entry ]
%tmp = phi i32 [ %start, %entry ], [ %tmp2, %while.body ]
%scevgep7 = getelementptr i32, ptr %lsr.iv, i32 1
%scevgep4 = getelementptr i32, ptr %lsr.iv4, i32 1
%tmp1 = load i32, ptr %scevgep7, align 4
%tmp2 = call i32 @llvm.loop.decrement.reg.i32.i32.i32(i32 %tmp, i32 1)
%half = lshr i32 %tmp1, 1
%cmp = icmp ult i32 %tmp, %limit
%res = select i1 %cmp, i32 %tmp1, i32 %half
store i32 %res, ptr %scevgep4, align 4
%scevgep1 = getelementptr i32, ptr %lsr.iv, i32 1
%scevgep5 = getelementptr i32, ptr %lsr.iv4, i32 1
%tmp3 = icmp ne i32 %tmp2, 0
br i1 %tmp3, label %while.body, label %while.end
while.end: ; preds = %while.body
ret i32 0
}
declare i32 @llvm.start.loop.iterations.i32(i32) #0
declare i32 @llvm.loop.decrement.reg.i32.i32.i32(i32, i32) #0
declare void @llvm.stackprotector(ptr, ptr) #1
attributes #0 = { noduplicate nounwind }
attributes #1 = { nounwind }
...
---
name: do_copy
alignment: 2
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
failedISel: false
tracksRegLiveness: true
hasWinCFI: false
registers: []
liveins:
- { reg: '$r0', virtual-reg: '' }
- { reg: '$r1', virtual-reg: '' }
- { reg: '$r2', virtual-reg: '' }
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 8
offsetAdjustment: 0
maxAlignment: 4
adjustsStack: false
hasCalls: false
stackProtector: ''
maxCallFrameSize: 0
cvBytesOfCalleeSavedRegisters: 0
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
localFrameSize: 0
savePoint: ''
restorePoint: ''
fixedStack: []
stack:
- { id: 0, name: '', type: spill-slot, offset: -4, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$lr', callee-saved-restored: false,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 1, name: '', type: spill-slot, offset: -8, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$r7', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
callSites: []
constants: []
machineFunctionInfo: {}
body: |
; CHECK-LABEL: name: do_copy
; CHECK: bb.0.entry:
; CHECK-NEXT: successors: %bb.1(0x80000000)
; CHECK-NEXT: liveins: $r0, $r1, $r2, $r7, $lr
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: frame-setup tPUSH 14 /* CC::al */, $noreg, killed $r7, killed $lr, implicit-def $sp, implicit $sp
; CHECK-NEXT: frame-setup CFI_INSTRUCTION def_cfa_offset 8
; CHECK-NEXT: frame-setup CFI_INSTRUCTION offset $lr, -4
; CHECK-NEXT: frame-setup CFI_INSTRUCTION offset $r7, -8
; CHECK-NEXT: $lr = tMOVr killed $r0, 14 /* CC::al */, $noreg
; CHECK-NEXT: renamable $r0, dead $cpsr = tSUBi3 killed renamable $r1, 4, 14 /* CC::al */, $noreg
; CHECK-NEXT: renamable $r1, dead $cpsr = tSUBi3 killed renamable $r2, 4, 14 /* CC::al */, $noreg
; CHECK-NEXT: renamable $r2 = t2LSRri renamable $lr, 1, 14 /* CC::al */, $noreg, $noreg
; CHECK-NEXT: $lr = tMOVr renamable $lr, 14 /* CC::al */, $noreg
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1.while.body:
; CHECK-NEXT: successors: %bb.1(0x7c000000), %bb.2(0x04000000)
; CHECK-NEXT: liveins: $lr, $r0, $r1, $r2
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: renamable $r3, renamable $r1 = t2LDR_PRE killed renamable $r1, 4, 14 /* CC::al */, $noreg :: (load (s32) from %ir.scevgep7)
; CHECK-NEXT: tCMPhir renamable $lr, renamable $r2, 14 /* CC::al */, $noreg, implicit-def $cpsr
; CHECK-NEXT: renamable $lr = t2SUBri killed renamable $lr, 1, 14 /* CC::al */, $noreg, $noreg
; CHECK-NEXT: t2IT 2, 8, implicit-def $itstate
; CHECK-NEXT: renamable $r3 = tLSRri $noreg, killed renamable $r3, 1, 2 /* CC::hs */, killed $cpsr, implicit renamable $r3, implicit killed $itstate
; CHECK-NEXT: early-clobber renamable $r0 = t2STR_PRE killed renamable $r3, killed renamable $r0, 4, 14 /* CC::al */, $noreg :: (store (s32) into %ir.scevgep4)
; CHECK-NEXT: t2CMPri renamable $lr, 0, 14 /* CC::al */, $noreg, implicit-def $cpsr
; CHECK-NEXT: tBcc %bb.1, 4 /* CC::mi */, killed $cpsr
; CHECK-NEXT: tB %bb.2, 14 /* CC::al */, $noreg
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.2.while.end:
; CHECK-NEXT: $r0, dead $cpsr = tMOVi8 0, 14 /* CC::al */, $noreg
; CHECK-NEXT: tPOP_RET 14 /* CC::al */, $noreg, def $r7, def $pc, implicit killed $r0
bb.0.entry:
successors: %bb.1(0x80000000)
liveins: $r0, $r1, $r2, $r7, $lr
frame-setup tPUSH 14, $noreg, killed $r7, killed $lr, implicit-def $sp, implicit $sp
frame-setup CFI_INSTRUCTION def_cfa_offset 8
frame-setup CFI_INSTRUCTION offset $lr, -4
frame-setup CFI_INSTRUCTION offset $r7, -8
$lr = tMOVr killed $r0, 14, $noreg
renamable $r0, dead $cpsr = tSUBi3 killed renamable $r1, 4, 14, $noreg
renamable $r1, dead $cpsr = tSUBi3 killed renamable $r2, 4, 14, $noreg
renamable $r2 = t2LSRri renamable $lr, 1, 14, $noreg, $noreg
$lr = t2DoLoopStart renamable $lr
bb.1.while.body:
successors: %bb.1(0x7c000000), %bb.2(0x04000000)
liveins: $lr, $r0, $r1, $r2
renamable $r3, renamable $r1 = t2LDR_PRE killed renamable $r1, 4, 14, $noreg :: (load (s32) from %ir.scevgep7)
tCMPhir renamable $lr, renamable $r2, 14, $noreg, implicit-def $cpsr
renamable $lr = t2LoopDec killed renamable $lr, 1
t2IT 2, 8, implicit-def $itstate
renamable $r3 = tLSRri $noreg, killed renamable $r3, 1, 2, killed $cpsr, implicit renamable $r3, implicit killed $itstate
early-clobber renamable $r0 = t2STR_PRE killed renamable $r3, killed renamable $r0, 4, 14, $noreg :: (store (s32) into %ir.scevgep4)
t2CMPri renamable $lr, 0, 14, $noreg, implicit-def $cpsr
tBcc %bb.1, 4, killed $cpsr
tB %bb.2, 14, $noreg
bb.2.while.end:
$r0, dead $cpsr = tMOVi8 0, 14, $noreg
tPOP_RET 14, $noreg, def $r7, def $pc, implicit killed $r0
...
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