; LLVM IR from lzyrapx/Competitive-Programming :: 51Nod (1049（最大子段和）)

; Unoptimized IR (clang -disable-llvm-passes):
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

%"class.std::basic_istream" = type { ptr, i64, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }

@now = external dso_local global i64, align 8
@n = external dso_local global i64, align 8
@ans = external dso_local global i64, align 8
@x = external dso_local global i64, align 8
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  %3 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(8) @n)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #4
  store i32 1, ptr %2, align 4, !tbaa !5
  br label %4

4:                                                ; preds = %25, %0
  %5 = load i32, ptr %2, align 4, !tbaa !5
  %6 = sext i32 %5 to i64
  %7 = load i64, ptr @n, align 8, !tbaa !9
  %8 = icmp sle i64 %6, %7
  br i1 %8, label %10, label %9

9:                                                ; preds = %4
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #4
  br label %28

10:                                               ; preds = %4
  %11 = load i64, ptr @now, align 8, !tbaa !9
  %12 = icmp slt i64 %11, 0
  br i1 %12, label %13, label %14

13:                                               ; preds = %10
  store i64 0, ptr @now, align 8, !tbaa !9
  br label %14

14:                                               ; preds = %13, %10
  %15 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(8) @x)
  %16 = load i64, ptr @x, align 8, !tbaa !9
  %17 = load i64, ptr @now, align 8, !tbaa !9
  %18 = add nsw i64 %17, %16
  store i64 %18, ptr @now, align 8, !tbaa !9
  %19 = load i64, ptr @now, align 8, !tbaa !9
  %20 = load i64, ptr @ans, align 8, !tbaa !9
  %21 = icmp sgt i64 %19, %20
  br i1 %21, label %22, label %24

22:                                               ; preds = %14
  %23 = load i64, ptr @now, align 8, !tbaa !9
  store i64 %23, ptr @ans, align 8, !tbaa !9
  br label %24

24:                                               ; preds = %22, %14
  br label %25

25:                                               ; preds = %24
  %26 = load i32, ptr %2, align 4, !tbaa !5
  %27 = add nsw i32 %26, 1
  store i32 %27, ptr %2, align 4, !tbaa !5
  br label %4, !llvm.loop !11

28:                                               ; preds = %9
  %29 = load i64, ptr @ans, align 8, !tbaa !9
  %30 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEx(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i64 noundef %29)
  %31 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %30, ptr noundef @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  ret i32 0
}

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 8 dereferenceable(8)) #1 align 2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEx(ptr noundef nonnull align 8 dereferenceable(8), i64 noundef) #1 align 2

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #1 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_(ptr noundef nonnull align 8 dereferenceable(8)) #3

attributes #0 = { mustprogress norecurse uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #1 = { mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #2 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #3 = { inlinehint mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #4 = { nounwind }

!llvm.module.flags = !{!0, !1, !2, !3}
!llvm.ident = !{!4}

!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{i32 8, !"PIC Level", i32 2}
!2 = !{i32 7, !"PIE Level", i32 2}
!3 = !{i32 7, !"uwtable", i32 2}
!4 = !{!"clang version 19.1.0 (git@github.com:llvm/llvm-project.git a4bf6cd7cfb1a1421ba92bca9d017b49936c55e4)"}
!5 = !{!6, !6, i64 0}
!6 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"long long", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}


; Optimized IR (opt -passes='default<O3>'):
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

%"class.std::basic_istream" = type { ptr, i64, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }

@now = external dso_local local_unnamed_addr global i64, align 8
@n = external dso_local global i64, align 8
@ans = external dso_local local_unnamed_addr global i64, align 8
@x = external dso_local global i64, align 8
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(8) @n)
  %2 = load i64, ptr @n, align 8, !tbaa !5
  %.not3 = icmp slt i64 %2, 1
  br i1 %.not3, label %.._crit_edge_crit_edge, label %.lr.ph.preheader

.._crit_edge_crit_edge:                           ; preds = %0
  %.pre6 = load i64, ptr @ans, align 8, !tbaa !5
  br label %._crit_edge

.lr.ph.preheader:                                 ; preds = %0
  %.pre = load i64, ptr @now, align 8, !tbaa !5
  br label %.lr.ph

._crit_edge:                                      ; preds = %17, %.._crit_edge_crit_edge
  %3 = phi i64 [ %.pre6, %.._crit_edge_crit_edge ], [ %18, %17 ]
  %4 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEx(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i64 noundef %3)
  %5 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %4, ptr noundef nonnull @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  ret i32 0

.lr.ph:                                           ; preds = %.lr.ph.preheader, %17
  %6 = phi i64 [ %.pre, %.lr.ph.preheader ], [ %13, %17 ]
  %indvars.iv = phi i64 [ 1, %.lr.ph.preheader ], [ %indvars.iv.next, %17 ]
  %7 = icmp slt i64 %6, 0
  br i1 %7, label %8, label %9

8:                                                ; preds = %.lr.ph
  store i64 0, ptr @now, align 8, !tbaa !5
  br label %9

9:                                                ; preds = %8, %.lr.ph
  %10 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(8) @x)
  %11 = load i64, ptr @x, align 8, !tbaa !5
  %12 = load i64, ptr @now, align 8, !tbaa !5
  %13 = add nsw i64 %12, %11
  store i64 %13, ptr @now, align 8, !tbaa !5
  %14 = load i64, ptr @ans, align 8, !tbaa !5
  %15 = icmp sgt i64 %13, %14
  br i1 %15, label %16, label %17

16:                                               ; preds = %9
  store i64 %13, ptr @ans, align 8, !tbaa !5
  br label %17

17:                                               ; preds = %9, %16
  %18 = phi i64 [ %14, %9 ], [ %13, %16 ]
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %19 = load i64, ptr @n, align 8, !tbaa !5
  %.not.not = icmp sgt i64 %19, %indvars.iv
  br i1 %.not.not, label %.lr.ph, label %._crit_edge, !llvm.loop !9
}

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #1 align 2

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEx(ptr noundef nonnull align 8 dereferenceable(8), i64 noundef) local_unnamed_addr #1 align 2

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #1 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_(ptr noundef nonnull align 8 dereferenceable(8)) #2

attributes #0 = { mustprogress norecurse uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #1 = { mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #2 = { inlinehint mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }

!llvm.module.flags = !{!0, !1, !2, !3}
!llvm.ident = !{!4}

!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{i32 8, !"PIC Level", i32 2}
!2 = !{i32 7, !"PIE Level", i32 2}
!3 = !{i32 7, !"uwtable", i32 2}
!4 = !{!"clang version 19.1.0 (git@github.com:llvm/llvm-project.git a4bf6cd7cfb1a1421ba92bca9d017b49936c55e4)"}
!5 = !{!6, !6, i64 0}
!6 = !{!"long long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass,TailCallElimPass