; LLVM IR from abeaumont/competitive-programming :: cses/2079.ll (Z4dfs2ii)

; 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 }

@n = external dso_local global i32, align 4
@d = external dso_local global [200000 x i32], align 16
@g = external dso_local global [200000 x %"class.std::vector"], align 16

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24)) #1 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24)) #1 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)) #2

; 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)) #1 align 2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; 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)) #1 align 2

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z4dfs2ii(i32 noundef %0, i32 noundef %1) #3 {
  %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
  store i32 %0, ptr %4, align 4, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #4
  %11 = load i32, ptr %4, align 4, !tbaa !5
  %12 = sext i32 %11 to i64
  %13 = getelementptr inbounds [200000 x %"class.std::vector"], ptr @g, i64 0, i64 %12
  store ptr %13, ptr %6, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #4
  %14 = load ptr, ptr %6, align 8, !tbaa !9
  %15 = call ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) %14) #4
  %16 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %7, i32 0, i32 0
  store ptr %15, ptr %16, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #4
  %17 = load ptr, ptr %6, align 8, !tbaa !9
  %18 = call ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24) %17) #4
  %19 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %8, i32 0, i32 0
  store ptr %18, ptr %19, align 8
  br label %20

20:                                               ; preds = %45, %2
  %21 = 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 %21, label %23, label %22

22:                                               ; preds = %20
  store i32 2, ptr %9, align 4
  br label %47

23:                                               ; preds = %20
  call void @llvm.lifetime.start.p0(i64 4, ptr %10) #4
  %24 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %7) #4
  %25 = load i32, ptr %24, align 4, !tbaa !5
  store i32 %25, ptr %10, align 4, !tbaa !5
  %26 = load i32, ptr %10, align 4, !tbaa !5
  %27 = load i32, ptr %5, align 4, !tbaa !5
  %28 = icmp ne i32 %26, %27
  br i1 %28, label %29, label %41

29:                                               ; preds = %23
  %30 = load i32, ptr %10, align 4, !tbaa !5
  %31 = sext i32 %30 to i64
  %32 = getelementptr inbounds [200000 x i32], ptr @d, i64 0, i64 %31
  %33 = load i32, ptr %32, align 4, !tbaa !5
  %34 = load i32, ptr @n, align 4, !tbaa !5
  %35 = sdiv i32 %34, 2
  %36 = icmp sgt i32 %33, %35
  br i1 %36, label %37, label %41

37:                                               ; preds = %29
  %38 = load i32, ptr %10, align 4, !tbaa !5
  %39 = load i32, ptr %4, align 4, !tbaa !5
  %40 = call noundef i32 @_Z4dfs2ii(i32 noundef %38, i32 noundef %39)
  store i32 %40, ptr %3, align 4
  store i32 1, ptr %9, align 4
  br label %42

41:                                               ; preds = %29, %23
  store i32 0, ptr %9, align 4
  br label %42

42:                                               ; preds = %41, %37
  call void @llvm.lifetime.end.p0(i64 4, ptr %10) #4
  %43 = load i32, ptr %9, align 4
  switch i32 %43, label %47 [
    i32 0, label %44
  ]

44:                                               ; preds = %42
  br label %45

45:                                               ; preds = %44
  %46 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEv(ptr noundef nonnull align 8 dereferenceable(8) %7) #4
  br label %20

47:                                               ; preds = %42, %22
  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
  %48 = load i32, ptr %9, align 4
  switch i32 %48, label %53 [
    i32 2, label %49
    i32 1, label %51
  ]

49:                                               ; preds = %47
  %50 = load i32, ptr %4, align 4, !tbaa !5
  store i32 %50, ptr %3, align 4
  br label %51

51:                                               ; preds = %49, %47
  %52 = load i32, ptr %3, align 4
  ret i32 %52

53:                                               ; preds = %47
  unreachable
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #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 = { 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 = !{!"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 }

@n = external dso_local local_unnamed_addr global i32, align 4
@d = external dso_local local_unnamed_addr global [200000 x i32], align 16
@g = external dso_local global [200000 x %"class.std::vector"], align 16

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #1 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #1 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 #2

; 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 #1 align 2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; 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 #1 align 2

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z4dfs2ii(i32 noundef %0, i32 noundef %1) local_unnamed_addr #1 {
  %3 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %4 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %5 = sext i32 %0 to i64
  %6 = getelementptr inbounds [200000 x %"class.std::vector"], ptr @g, i64 0, i64 %5
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %3) #3
  %7 = tail call ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) %6) #3
  store ptr %7, ptr %3, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %4) #3
  %8 = tail call ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24) %6) #3
  store ptr %8, ptr %4, align 8
  %9 = call noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8) %3, ptr noundef nonnull align 8 dereferenceable(8) %4) #3
  br i1 %9, label %.lr.ph, label %.loopexit

.lr.ph:                                           ; preds = %2, %21
  %10 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %3) #3
  %11 = load i32, ptr %10, align 4, !tbaa !5
  %.not = icmp eq i32 %11, %1
  br i1 %.not, label %21, label %12

12:                                               ; preds = %.lr.ph
  %13 = sext i32 %11 to i64
  %14 = getelementptr inbounds [200000 x i32], ptr @d, i64 0, i64 %13
  %15 = load i32, ptr %14, align 4, !tbaa !5
  %16 = load i32, ptr @n, align 4, !tbaa !5
  %17 = sdiv i32 %16, 2
  %18 = icmp sgt i32 %15, %17
  br i1 %18, label %19, label %21

19:                                               ; preds = %12
  %20 = call noundef i32 @_Z4dfs2ii(i32 noundef %11, i32 noundef %0)
  br label %.loopexit

21:                                               ; preds = %12, %.lr.ph
  %22 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEv(ptr noundef nonnull align 8 dereferenceable(8) %3) #3
  %23 = call noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8) %3, ptr noundef nonnull align 8 dereferenceable(8) %4) #3
  br i1 %23, label %.lr.ph, label %.loopexit

.loopexit:                                        ; preds = %21, %2, %19
  %spec.select = phi i32 [ %20, %19 ], [ %0, %2 ], [ %0, %21 ]
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %4) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %3) #3
  ret i32 %spec.select
}

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


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