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|
# RUN: llc -mtriple=armv8.1m.main -run-pass=arm-low-overhead-loops %s -o - | FileCheck %s
# CHECK: entry:
# CHECK: $lr = t2DLS
# CHECK: for.body:
# CHECK: $lr = t2LEUpdate renamable $lr
--- |
target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
target triple = "thumbv8.1m.main-unknown-unknown"
; Function Attrs: norecurse nounwind
define dso_local arm_aapcscc void @size_limit(i32* nocapture %a, i32* nocapture readonly %b, i32* nocapture readonly %c, i32 %N) local_unnamed_addr #0 {
entry:
%cmp8 = icmp eq i32 %N, 0
br i1 %cmp8, label %for.cond.cleanup, label %for.body.preheader
for.body.preheader: ; preds = %entry
%scevgep = getelementptr i32, i32* %a, i32 -1
%scevgep4 = getelementptr i32, i32* %c, i32 -1
%scevgep8 = getelementptr i32, i32* %b, i32 -1
call void @llvm.set.loop.iterations.i32(i32 %N)
br label %for.body
for.cond.cleanup: ; preds = %for.body, %entry
ret void
for.body: ; preds = %for.body, %for.body.preheader
%lsr.iv9 = phi i32* [ %scevgep8, %for.body.preheader ], [ %scevgep10, %for.body ]
%lsr.iv5 = phi i32* [ %scevgep4, %for.body.preheader ], [ %scevgep6, %for.body ]
%lsr.iv1 = phi i32* [ %scevgep, %for.body.preheader ], [ %scevgep2, %for.body ]
%0 = phi i32 [ %N, %for.body.preheader ], [ %3, %for.body ]
%size = call i32 @llvm.arm.space(i32 4070, i32 undef)
%scevgep11 = getelementptr i32, i32* %lsr.iv9, i32 1
%1 = load i32, i32* %scevgep11, align 4, !tbaa !3
%scevgep7 = getelementptr i32, i32* %lsr.iv5, i32 1
%2 = load i32, i32* %scevgep7, align 4, !tbaa !3
%mul = mul nsw i32 %2, %1
%scevgep3 = getelementptr i32, i32* %lsr.iv1, i32 1
store i32 %mul, i32* %scevgep3, align 4, !tbaa !3
%scevgep2 = getelementptr i32, i32* %lsr.iv1, i32 1
%scevgep6 = getelementptr i32, i32* %lsr.iv5, i32 1
%scevgep10 = getelementptr i32, i32* %lsr.iv9, i32 1
%3 = call i32 @llvm.loop.decrement.reg.i32.i32.i32(i32 %0, i32 1)
%4 = icmp ne i32 %3, 0
br i1 %4, label %for.body, label %for.cond.cleanup
}
; Function Attrs: nounwind
declare i32 @llvm.arm.space(i32, i32) #1
; Function Attrs: noduplicate nounwind
declare void @llvm.set.loop.iterations.i32(i32) #2
; Function Attrs: noduplicate nounwind
declare i32 @llvm.loop.decrement.reg.i32.i32.i32(i32, i32) #2
; Function Attrs: nounwind
declare void @llvm.stackprotector(i8*, i8**) #1
attributes #0 = { norecurse nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="generic" "target-features"="+armv8.1-m.main,+hwdiv,+ras,+soft-float,+strict-align,+thumb-mode,-crypto,-d32,-dotprod,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-neon,-vfp2,-vfp2d16,-vfp2d16sp,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "unsafe-fp-math"="false" "use-soft-float"="true" }
attributes #1 = { nounwind }
attributes #2 = { noduplicate nounwind }
!llvm.module.flags = !{!0, !1}
!llvm.ident = !{!2}
!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{i32 1, !"min_enum_size", i32 4}
!2 = !{!"clang version 9.0.0 (http://llvm.org/git/clang.git a9c7c0fc5d468f3d18a5c6beb697ab0d5be2ff4c) (http://llvm.org/git/llvm.git f34bff0c141a04a5182d57e2cfb1e4bc582c81b0)"}
!3 = !{!4, !4, i64 0}
!4 = !{!"int", !5, i64 0}
!5 = !{!"omnipotent char", !6, i64 0}
!6 = !{!"Simple C/C++ TBAA"}
...
---
name: size_limit
alignment: 1
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
failedISel: false
tracksRegLiveness: false
hasWinCFI: false
registers: []
liveins:
- { reg: '$r0', virtual-reg: '' }
- { reg: '$r1', virtual-reg: '' }
- { reg: '$r2', virtual-reg: '' }
- { reg: '$r3', virtual-reg: '' }
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 8
offsetAdjustment: 0
maxAlignment: 4
adjustsStack: false
hasCalls: false
stackProtector: ''
maxCallFrameSize: 0
cvBytesOfCalleeSavedRegisters: 0
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
localFrameSize: 0
savePoint: ''
restorePoint: ''
fixedStack: []
stack:
- { id: 0, name: '', type: spill-slot, offset: -4, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$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: '' }
constants: []
machineFunctionInfo: {}
body: |
bb.0.entry:
successors: %bb.1(0x80000000)
frame-setup tPUSH 14, $noreg, $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
$r7 = frame-setup tMOVr $sp, 14, $noreg
frame-setup CFI_INSTRUCTION def_cfa_register $r7
tCMPi8 $r3, 0, 14, $noreg, implicit-def $cpsr
t2IT 0, 8, implicit-def $itstate
tPOP_RET 0, killed $cpsr, def $r7, def $pc, implicit killed $itstate
renamable $r1, dead $cpsr = tSUBi8 killed renamable $r1, 4, 14, $noreg
renamable $r2, dead $cpsr = tSUBi8 killed renamable $r2, 4, 14, $noreg
renamable $r0, dead $cpsr = tSUBi8 killed renamable $r0, 4, 14, $noreg
$lr = tMOVr $r3, 14, $noreg
t2DoLoopStart killed $r3
bb.1.for.body:
successors: %bb.1(0x7c000000), %bb.2(0x04000000)
dead renamable $r3 = SPACE 4070, undef renamable $r0
renamable $r12, renamable $r1 = t2LDR_PRE killed renamable $r1, 4, 14, $noreg :: (load 4 from %ir.scevgep11, !tbaa !3)
renamable $r3, renamable $r2 = t2LDR_PRE killed renamable $r2, 4, 14, $noreg :: (load 4 from %ir.scevgep7, !tbaa !3)
renamable $r3 = nsw t2MUL killed renamable $r3, killed renamable $r12, 14, $noreg
early-clobber renamable $r0 = t2STR_PRE killed renamable $r3, killed renamable $r0, 4, 14, $noreg :: (store 4 into %ir.scevgep3, !tbaa !3)
renamable $lr = t2LoopDec killed renamable $lr, 1
t2LoopEnd renamable $lr, %bb.1
tB %bb.2, 14, $noreg
bb.2.for.cond.cleanup:
tPOP_RET 14, $noreg, def $r7, def $pc
...
|
