; LLVM IR from tangjz/acm-icpc :: codeforces/complete/472D.ll (Z3bfsi)

; 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<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl" }
%"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl" = type { %"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl_data" }
%"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl_data" = type { ptr, ptr, ptr }
%"class.__gnu_cxx::__normal_iterator" = type { ptr }
%"struct.std::pair" = type { i32, i32 }

@g2 = external dso_local global [2001 x [2001 x i32]], align 16
@s = external dso_local global i32, align 4
@dist = external dso_local global i32, align 4
@vis = external dso_local global [2001 x i32], align 16
@e = external dso_local global [2001 x %"class.std::vector"], align 16

; Function Attrs: mustprogress uwtable
define dso_local void @_Z3bfsi(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %4 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  store i32 %0, ptr %2, align 4, !tbaa !5
  %5 = load i32, ptr %2, align 4, !tbaa !5
  %6 = sext i32 %5 to i64
  %7 = getelementptr inbounds [2001 x i32], ptr @vis, i64 0, i64 %6
  store i32 1, ptr %7, align 4, !tbaa !5
  %8 = load i32, ptr @dist, align 4, !tbaa !5
  %9 = load i32, ptr @s, align 4, !tbaa !5
  %10 = sext i32 %9 to i64
  %11 = getelementptr inbounds [2001 x [2001 x i32]], ptr @g2, i64 0, i64 %10
  %12 = load i32, ptr %2, align 4, !tbaa !5
  %13 = sext i32 %12 to i64
  %14 = getelementptr inbounds [2001 x i32], ptr %11, i64 0, i64 %13
  store i32 %8, ptr %14, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #4
  %15 = load i32, ptr %2, align 4, !tbaa !5
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds [2001 x %"class.std::vector"], ptr @e, i64 0, i64 %16
  %18 = call ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) %17) #4
  %19 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %3, i32 0, i32 0
  store ptr %18, ptr %19, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  %20 = load i32, ptr %2, align 4, !tbaa !5
  %21 = sext i32 %20 to i64
  %22 = getelementptr inbounds [2001 x %"class.std::vector"], ptr @e, i64 0, i64 %21
  %23 = call ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE3endEv(ptr noundef nonnull align 8 dereferenceable(24) %22) #4
  %24 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %4, i32 0, i32 0
  store ptr %23, ptr %24, align 8
  br label %25

25:                                               ; preds = %51, %1
  %26 = call noundef zeroext i1 @_ZN9__gnu_cxxneIPSt4pairIiiESt6vectorIS2_SaIS2_EEEEbRKNS_17__normal_iteratorIT_T0_EESC_(ptr noundef nonnull align 8 dereferenceable(8) %3, ptr noundef nonnull align 8 dereferenceable(8) %4) #4
  br i1 %26, label %28, label %27

27:                                               ; preds = %25
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #4
  br label %53

28:                                               ; preds = %25
  %29 = call noundef ptr @_ZNK9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEptEv(ptr noundef nonnull align 8 dereferenceable(8) %3) #4
  %30 = getelementptr inbounds %"struct.std::pair", ptr %29, i32 0, i32 1
  %31 = load i32, ptr %30, align 4, !tbaa !9
  %32 = sext i32 %31 to i64
  %33 = getelementptr inbounds [2001 x i32], ptr @vis, i64 0, i64 %32
  %34 = load i32, ptr %33, align 4, !tbaa !5
  %35 = icmp ne i32 %34, 0
  br i1 %35, label %50, label %36

36:                                               ; preds = %28
  %37 = call noundef ptr @_ZNK9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEptEv(ptr noundef nonnull align 8 dereferenceable(8) %3) #4
  %38 = getelementptr inbounds %"struct.std::pair", ptr %37, i32 0, i32 0
  %39 = load i32, ptr %38, align 4, !tbaa !11
  %40 = load i32, ptr @dist, align 4, !tbaa !5
  %41 = add nsw i32 %40, %39
  store i32 %41, ptr @dist, align 4, !tbaa !5
  %42 = call noundef ptr @_ZNK9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEptEv(ptr noundef nonnull align 8 dereferenceable(8) %3) #4
  %43 = getelementptr inbounds %"struct.std::pair", ptr %42, i32 0, i32 1
  %44 = load i32, ptr %43, align 4, !tbaa !9
  call void @_Z3bfsi(i32 noundef %44)
  %45 = call noundef ptr @_ZNK9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEptEv(ptr noundef nonnull align 8 dereferenceable(8) %3) #4
  %46 = getelementptr inbounds %"struct.std::pair", ptr %45, i32 0, i32 0
  %47 = load i32, ptr %46, align 4, !tbaa !11
  %48 = load i32, ptr @dist, align 4, !tbaa !5
  %49 = sub nsw i32 %48, %47
  store i32 %49, ptr @dist, align 4, !tbaa !5
  br label %50

50:                                               ; preds = %36, %28
  br label %51

51:                                               ; preds = %50
  %52 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZN9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEppEv(ptr noundef nonnull align 8 dereferenceable(8) %3) #4
  br label %25, !llvm.loop !12

53:                                               ; preds = %27
  ret void
}

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

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(24)) #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE3endEv(ptr noundef nonnull align 8 dereferenceable(24)) #2 align 2

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZN9__gnu_cxxneIPSt4pairIiiESt6vectorIS2_SaIS2_EEEEbRKNS_17__normal_iteratorIT_T0_EESC_(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef nonnull align 8 dereferenceable(8)) #3

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef ptr @_ZNK9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEptEv(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_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEppEv(ptr noundef nonnull align 8 dereferenceable(8)) #2 align 2

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

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, !6, i64 4}
!10 = !{!"_ZTSSt4pairIiiE", !6, i64 0, !6, i64 4}
!11 = !{!10, !6, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"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::vector" = type { %"struct.std::_Vector_base" }
%"struct.std::_Vector_base" = type { %"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl" }
%"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl" = type { %"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl_data" }
%"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl_data" = type { ptr, ptr, ptr }
%"class.__gnu_cxx::__normal_iterator" = type { ptr }

@g2 = external dso_local local_unnamed_addr global [2001 x [2001 x i32]], align 16
@s = external dso_local local_unnamed_addr global i32, align 4
@dist = external dso_local local_unnamed_addr global i32, align 4
@vis = external dso_local local_unnamed_addr global [2001 x i32], align 16
@e = external dso_local global [2001 x %"class.std::vector"], align 16

; Function Attrs: mustprogress nounwind uwtable
define dso_local void @_Z3bfsi(i32 noundef %0) local_unnamed_addr #0 {
  %2 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %3 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %4 = sext i32 %0 to i64
  %5 = getelementptr inbounds [2001 x i32], ptr @vis, i64 0, i64 %4
  store i32 1, ptr %5, align 4, !tbaa !5
  %6 = load i32, ptr @dist, align 4, !tbaa !5
  %7 = load i32, ptr @s, align 4, !tbaa !5
  %8 = sext i32 %7 to i64
  %9 = getelementptr inbounds [2001 x [2001 x i32]], ptr @g2, i64 0, i64 %8, i64 %4
  store i32 %6, ptr %9, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %2) #3
  %10 = getelementptr inbounds [2001 x %"class.std::vector"], ptr @e, i64 0, i64 %4
  %11 = tail call ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) %10) #3
  store ptr %11, ptr %2, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %3) #3
  %12 = tail call ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE3endEv(ptr noundef nonnull align 8 dereferenceable(24) %10) #3
  store ptr %12, ptr %3, align 8
  %13 = call noundef zeroext i1 @_ZN9__gnu_cxxneIPSt4pairIiiESt6vectorIS2_SaIS2_EEEEbRKNS_17__normal_iteratorIT_T0_EESC_(ptr noundef nonnull align 8 dereferenceable(8) %2, ptr noundef nonnull align 8 dereferenceable(8) %3) #3
  br i1 %13, label %.lr.ph, label %._crit_edge

._crit_edge:                                      ; preds = %32, %1
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %3) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %2) #3
  ret void

.lr.ph:                                           ; preds = %1, %32
  %14 = call noundef ptr @_ZNK9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEptEv(ptr noundef nonnull align 8 dereferenceable(8) %2) #3
  %15 = getelementptr inbounds i8, ptr %14, i64 4
  %16 = load i32, ptr %15, align 4, !tbaa !9
  %17 = sext i32 %16 to i64
  %18 = getelementptr inbounds [2001 x i32], ptr @vis, i64 0, i64 %17
  %19 = load i32, ptr %18, align 4, !tbaa !5
  %.not = icmp eq i32 %19, 0
  br i1 %.not, label %20, label %32

20:                                               ; preds = %.lr.ph
  %21 = call noundef ptr @_ZNK9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEptEv(ptr noundef nonnull align 8 dereferenceable(8) %2) #3
  %22 = load i32, ptr %21, align 4, !tbaa !11
  %23 = load i32, ptr @dist, align 4, !tbaa !5
  %24 = add nsw i32 %23, %22
  store i32 %24, ptr @dist, align 4, !tbaa !5
  %25 = call noundef ptr @_ZNK9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEptEv(ptr noundef nonnull align 8 dereferenceable(8) %2) #3
  %26 = getelementptr inbounds i8, ptr %25, i64 4
  %27 = load i32, ptr %26, align 4, !tbaa !9
  call void @_Z3bfsi(i32 noundef %27)
  %28 = call noundef ptr @_ZNK9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEptEv(ptr noundef nonnull align 8 dereferenceable(8) %2) #3
  %29 = load i32, ptr %28, align 4, !tbaa !11
  %30 = load i32, ptr @dist, align 4, !tbaa !5
  %31 = sub nsw i32 %30, %29
  store i32 %31, ptr @dist, align 4, !tbaa !5
  br label %32

32:                                               ; preds = %.lr.ph, %20
  %33 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZN9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEppEv(ptr noundef nonnull align 8 dereferenceable(8) %2) #3
  %34 = call noundef zeroext i1 @_ZN9__gnu_cxxneIPSt4pairIiiESt6vectorIS2_SaIS2_EEEEbRKNS_17__normal_iteratorIT_T0_EESC_(ptr noundef nonnull align 8 dereferenceable(8) %2, ptr noundef nonnull align 8 dereferenceable(8) %3) #3
  br i1 %34, label %.lr.ph, label %._crit_edge, !llvm.loop !12
}

; 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 nounwind uwtable
declare dso_local ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE3endEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #0 align 2

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZN9__gnu_cxxneIPSt4pairIiiESt6vectorIS2_SaIS2_EEEEbRKNS_17__normal_iteratorIT_T0_EESC_(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef ptr @_ZNK9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEptEv(ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 8 dereferenceable(8) ptr @_ZN9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS2_SaIS2_EEEppEv(ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #0 align 2

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

attributes #0 = { 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 #1 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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 #3 = { 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, !6, i64 4}
!10 = !{!"_ZTSSt4pairIiiE", !6, i64 0, !6, i64 4}
!11 = !{!10, !6, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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