; LLVM IR from eyangch/competitive-programming :: USACOcontests/gold/2019.12/milkvisits.ll (Z3dfsii)

; 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::vector" = type { %"struct.std::_Vector_base" }
%"struct.std::_Vector_base" = type { %"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl" }
%"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl" = type { %"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl_data" }
%"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl_data" = type { ptr, ptr, ptr }
%"class.__gnu_cxx::__normal_iterator" = type { ptr }

@t = external dso_local global [100000 x i32], align 16
@graph = external dso_local global [100000 x %"class.std::vector"], align 16
@fwd = external dso_local global [100000 x %"class.std::vector"], align 16
@bck = external dso_local global [100000 x %"class.std::vector"], align 16
@o1 = external dso_local global [100000 x i32], align 16
@cnttrav = external dso_local global i32, align 4

; Function Attrs: mustprogress uwtable
define dso_local void @_Z3dfsii(i32 noundef %0, i32 noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca ptr, align 8
  %7 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %8 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %9 = alloca i32, align 4
  %10 = alloca i32, align 4
  %11 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !5
  %12 = load i32, ptr @cnttrav, align 4, !tbaa !5
  %13 = load i32, ptr %3, align 4, !tbaa !5
  %14 = sext i32 %13 to i64
  %15 = getelementptr inbounds [100000 x i32], ptr @o1, i64 0, i64 %14
  store i32 %12, ptr %15, align 4, !tbaa !5
  %16 = load i32, ptr %3, align 4, !tbaa !5
  %17 = sext i32 %16 to i64
  %18 = getelementptr inbounds [100000 x i32], ptr @t, i64 0, i64 %17
  %19 = load i32, ptr %18, align 4, !tbaa !5
  %20 = sext i32 %19 to i64
  %21 = getelementptr inbounds [100000 x %"class.std::vector"], ptr @fwd, i64 0, i64 %20
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #4
  %22 = load i32, ptr @cnttrav, align 4, !tbaa !5
  %23 = add nsw i32 %22, 1
  store i32 %23, ptr @cnttrav, align 4, !tbaa !5
  store i32 %22, ptr %5, align 4, !tbaa !5
  call void @_ZNSt6vectorIiSaIiEE9push_backEOi(ptr noundef nonnull align 8 dereferenceable(24) %21, ptr noundef nonnull align 4 dereferenceable(4) %5)
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #4
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #4
  %24 = load i32, ptr %3, align 4, !tbaa !5
  %25 = sext i32 %24 to i64
  %26 = getelementptr inbounds [100000 x %"class.std::vector"], ptr @graph, i64 0, i64 %25
  store ptr %26, ptr %6, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #4
  %27 = load ptr, ptr %6, align 8, !tbaa !9
  %28 = call ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) %27) #4
  %29 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %7, i32 0, i32 0
  store ptr %28, ptr %29, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #4
  %30 = load ptr, ptr %6, align 8, !tbaa !9
  %31 = call ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24) %30) #4
  %32 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %8, i32 0, i32 0
  store ptr %31, ptr %32, align 8
  br label %33

33:                                               ; preds = %49, %2
  %34 = call noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8) %7, ptr noundef nonnull align 8 dereferenceable(8) %8) #4
  br i1 %34, label %36, label %35

35:                                               ; preds = %33
  store i32 2, ptr %9, align 4
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #4
  br label %51

36:                                               ; preds = %33
  call void @llvm.lifetime.start.p0(i64 4, ptr %10) #4
  %37 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %7) #4
  %38 = load i32, ptr %37, align 4, !tbaa !5
  store i32 %38, ptr %10, align 4, !tbaa !5
  %39 = load i32, ptr %10, align 4, !tbaa !5
  %40 = load i32, ptr %4, align 4, !tbaa !5
  %41 = icmp eq i32 %39, %40
  br i1 %41, label %42, label %43

42:                                               ; preds = %36
  store i32 3, ptr %9, align 4
  br label %46

43:                                               ; preds = %36
  %44 = load i32, ptr %10, align 4, !tbaa !5
  %45 = load i32, ptr %3, align 4, !tbaa !5
  call void @_Z3dfsii(i32 noundef %44, i32 noundef %45)
  store i32 0, ptr %9, align 4
  br label %46

46:                                               ; preds = %43, %42
  call void @llvm.lifetime.end.p0(i64 4, ptr %10) #4
  %47 = load i32, ptr %9, align 4
  switch i32 %47, label %60 [
    i32 0, label %48
    i32 3, label %49
  ]

48:                                               ; preds = %46
  br label %49

49:                                               ; preds = %48, %46
  %50 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEv(ptr noundef nonnull align 8 dereferenceable(8) %7) #4
  br label %33

51:                                               ; preds = %35
  %52 = load i32, ptr %3, align 4, !tbaa !5
  %53 = sext i32 %52 to i64
  %54 = getelementptr inbounds [100000 x i32], ptr @t, i64 0, i64 %53
  %55 = load i32, ptr %54, align 4, !tbaa !5
  %56 = sext i32 %55 to i64
  %57 = getelementptr inbounds [100000 x %"class.std::vector"], ptr @bck, i64 0, i64 %56
  call void @llvm.lifetime.start.p0(i64 4, ptr %11) #4
  %58 = load i32, ptr @cnttrav, align 4, !tbaa !5
  %59 = add nsw i32 %58, 1
  store i32 %59, ptr @cnttrav, align 4, !tbaa !5
  store i32 %58, ptr %11, align 4, !tbaa !5
  call void @_ZNSt6vectorIiSaIiEE9push_backEOi(ptr noundef nonnull align 8 dereferenceable(24) %57, ptr noundef nonnull align 4 dereferenceable(4) %11)
  call void @llvm.lifetime.end.p0(i64 4, ptr %11) #4
  ret void

60:                                               ; preds = %46
  unreachable
}

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEE9push_backEOi(ptr noundef nonnull align 8 dereferenceable(24), ptr noundef nonnull align 4 dereferenceable(4)) #0 align 2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24)) #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24)) #2 align 2

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef nonnull align 8 dereferenceable(8)) #3

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8)) #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 8 dereferenceable(8) ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEv(ptr noundef nonnull align 8 dereferenceable(8)) #2 align 2

attributes #0 = { 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 #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { mustprogress nounwind 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 #3 = { inlinehint mustprogress nounwind 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 = !{!"any pointer", !7, i64 0}


; 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::vector" = type { %"struct.std::_Vector_base" }
%"struct.std::_Vector_base" = type { %"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl" }
%"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl" = type { %"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl_data" }
%"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl_data" = type { ptr, ptr, ptr }
%"class.__gnu_cxx::__normal_iterator" = type { ptr }

@t = external dso_local local_unnamed_addr global [100000 x i32], align 16
@graph = external dso_local global [100000 x %"class.std::vector"], align 16
@fwd = external dso_local global [100000 x %"class.std::vector"], align 16
@bck = external dso_local global [100000 x %"class.std::vector"], align 16
@o1 = external dso_local local_unnamed_addr global [100000 x i32], align 16
@cnttrav = external dso_local local_unnamed_addr global i32, align 4

; Function Attrs: mustprogress uwtable
define dso_local void @_Z3dfsii(i32 noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = alloca i32, align 4
  %4 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %5 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %6 = alloca i32, align 4
  %7 = load i32, ptr @cnttrav, align 4, !tbaa !5
  %8 = sext i32 %0 to i64
  %9 = getelementptr inbounds [100000 x i32], ptr @o1, i64 0, i64 %8
  store i32 %7, ptr %9, align 4, !tbaa !5
  %10 = getelementptr inbounds [100000 x i32], ptr @t, i64 0, i64 %8
  %11 = load i32, ptr %10, align 4, !tbaa !5
  %12 = sext i32 %11 to i64
  %13 = getelementptr inbounds [100000 x %"class.std::vector"], ptr @fwd, i64 0, i64 %12
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %3) #4
  %14 = add nsw i32 %7, 1
  store i32 %14, ptr @cnttrav, align 4, !tbaa !5
  store i32 %7, ptr %3, align 4, !tbaa !5
  call void @_ZNSt6vectorIiSaIiEE9push_backEOi(ptr noundef nonnull align 8 dereferenceable(24) %13, ptr noundef nonnull align 4 dereferenceable(4) %3)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %3) #4
  %15 = getelementptr inbounds [100000 x %"class.std::vector"], ptr @graph, i64 0, i64 %8
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %4) #4
  %16 = call ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) %15) #4
  store ptr %16, ptr %4, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %5) #4
  %17 = call ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24) %15) #4
  store ptr %17, ptr %5, align 8
  %18 = call noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8) %4, ptr noundef nonnull align 8 dereferenceable(8) %5) #4
  br i1 %18, label %.lr.ph, label %._crit_edge

._crit_edge:                                      ; preds = %28, %2
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %5) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %4) #4
  %19 = load i32, ptr %10, align 4, !tbaa !5
  %20 = sext i32 %19 to i64
  %21 = getelementptr inbounds [100000 x %"class.std::vector"], ptr @bck, i64 0, i64 %20
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %6) #4
  %22 = load i32, ptr @cnttrav, align 4, !tbaa !5
  %23 = add nsw i32 %22, 1
  store i32 %23, ptr @cnttrav, align 4, !tbaa !5
  store i32 %22, ptr %6, align 4, !tbaa !5
  call void @_ZNSt6vectorIiSaIiEE9push_backEOi(ptr noundef nonnull align 8 dereferenceable(24) %21, ptr noundef nonnull align 4 dereferenceable(4) %6)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %6) #4
  ret void

.lr.ph:                                           ; preds = %2, %28
  %24 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %4) #4
  %25 = load i32, ptr %24, align 4, !tbaa !5
  %26 = icmp eq i32 %25, %1
  br i1 %26, label %28, label %27

27:                                               ; preds = %.lr.ph
  call void @_Z3dfsii(i32 noundef %25, i32 noundef %0)
  br label %28

28:                                               ; preds = %.lr.ph, %27
  %29 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEv(ptr noundef nonnull align 8 dereferenceable(8) %4) #4
  %30 = call noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8) %4, ptr noundef nonnull align 8 dereferenceable(8) %5) #4
  br i1 %30, label %.lr.ph, label %._crit_edge
}

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEE9push_backEOi(ptr noundef nonnull align 8 dereferenceable(24), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #2 align 2

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #3

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 8 dereferenceable(8) ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEv(ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #2 align 2

attributes #0 = { 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 #1 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { mustprogress nounwind 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 #3 = { inlinehint mustprogress nounwind 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"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass