; LLVM IR from eyangch/competitive-programming :: USACOcontests/platinum/2015.12/maxflow.ll (Z6dfsansii)

; 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 }

@graph = external dso_local global [50000 x %"class.std::vector"], align 16
@pfx = external dso_local global [50000 x i32], align 16
@ans = external dso_local global i32, align 4

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

; 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 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: 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 @_Z6dfsansii(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 %3, align 4, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #4
  %11 = load i32, ptr %3, align 4, !tbaa !5
  %12 = sext i32 %11 to i64
  %13 = getelementptr inbounds [50000 x i32], ptr @pfx, i64 0, i64 %12
  %14 = load i32, ptr %13, align 4, !tbaa !5
  store i32 %14, ptr %5, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #4
  %15 = load i32, ptr %3, align 4, !tbaa !5
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds [50000 x %"class.std::vector"], ptr @graph, i64 0, i64 %16
  store ptr %17, ptr %6, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #4
  %18 = load ptr, ptr %6, align 8, !tbaa !9
  %19 = call ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) %18) #4
  %20 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %7, i32 0, i32 0
  store ptr %19, ptr %20, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #4
  %21 = load ptr, ptr %6, align 8, !tbaa !9
  %22 = call ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24) %21) #4
  %23 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %8, i32 0, i32 0
  store ptr %22, ptr %23, align 8
  br label %24

24:                                               ; preds = %43, %2
  %25 = 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 %25, label %27, label %26

26:                                               ; preds = %24
  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 %45

27:                                               ; preds = %24
  call void @llvm.lifetime.start.p0(i64 4, ptr %10) #4
  %28 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %7) #4
  %29 = load i32, ptr %28, align 4, !tbaa !5
  store i32 %29, ptr %10, align 4, !tbaa !5
  %30 = load i32, ptr %10, align 4, !tbaa !5
  %31 = load i32, ptr %4, align 4, !tbaa !5
  %32 = icmp eq i32 %30, %31
  br i1 %32, label %33, label %34

33:                                               ; preds = %27
  store i32 3, ptr %9, align 4
  br label %40

34:                                               ; preds = %27
  %35 = load i32, ptr %10, align 4, !tbaa !5
  %36 = load i32, ptr %3, align 4, !tbaa !5
  %37 = call noundef i32 @_Z6dfsansii(i32 noundef %35, i32 noundef %36)
  %38 = load i32, ptr %5, align 4, !tbaa !5
  %39 = add nsw i32 %38, %37
  store i32 %39, ptr %5, align 4, !tbaa !5
  store i32 0, ptr %9, align 4
  br label %40

40:                                               ; preds = %34, %33
  call void @llvm.lifetime.end.p0(i64 4, ptr %10) #4
  %41 = load i32, ptr %9, align 4
  switch i32 %41, label %49 [
    i32 0, label %42
    i32 3, label %43
  ]

42:                                               ; preds = %40
  br label %43

43:                                               ; preds = %42, %40
  %44 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEv(ptr noundef nonnull align 8 dereferenceable(8) %7) #4
  br label %24

45:                                               ; preds = %26
  %46 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3maxIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4) @ans, ptr noundef nonnull align 4 dereferenceable(4) %5)
  %47 = load i32, ptr %46, align 4, !tbaa !5
  store i32 %47, ptr @ans, align 4, !tbaa !5
  %48 = load i32, ptr %5, align 4, !tbaa !5
  store i32 1, ptr %9, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #4
  ret i32 %48

49:                                               ; preds = %40
  unreachable
}

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3maxIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4), ptr noundef nonnull align 4 dereferenceable(4)) #2

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 }

@graph = external dso_local global [50000 x %"class.std::vector"], align 16
@pfx = external dso_local local_unnamed_addr global [50000 x i32], align 16
@ans = external dso_local global i32, align 4

; 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 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 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 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 @_Z6dfsansii(i32 noundef %0, i32 noundef %1) local_unnamed_addr #1 {
  %3 = alloca i32, align 4
  %4 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %5 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %3) #3
  %6 = sext i32 %0 to i64
  %7 = getelementptr inbounds [50000 x i32], ptr @pfx, i64 0, i64 %6
  %8 = load i32, ptr %7, align 4, !tbaa !5
  store i32 %8, ptr %3, align 4, !tbaa !5
  %9 = getelementptr inbounds [50000 x %"class.std::vector"], ptr @graph, i64 0, i64 %6
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %4) #3
  %10 = tail call ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) %9) #3
  store ptr %10, ptr %4, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %5) #3
  %11 = tail call ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24) %9) #3
  store ptr %11, ptr %5, align 8
  %12 = 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) #3
  br i1 %12, label %.lr.ph, label %._crit_edge

._crit_edge:                                      ; preds = %23, %2
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %5) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %4) #3
  %13 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3maxIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4) @ans, ptr noundef nonnull align 4 dereferenceable(4) %3)
  %14 = load i32, ptr %13, align 4, !tbaa !5
  store i32 %14, ptr @ans, align 4, !tbaa !5
  %15 = load i32, ptr %3, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %3) #3
  ret i32 %15

.lr.ph:                                           ; preds = %2, %23
  %16 = phi i32 [ %24, %23 ], [ %8, %2 ]
  %17 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %4) #3
  %18 = load i32, ptr %17, align 4, !tbaa !5
  %19 = icmp eq i32 %18, %1
  br i1 %19, label %23, label %20

20:                                               ; preds = %.lr.ph
  %21 = call noundef i32 @_Z6dfsansii(i32 noundef %18, i32 noundef %0)
  %22 = add nsw i32 %16, %21
  store i32 %22, ptr %3, align 4, !tbaa !5
  br label %23

23:                                               ; preds = %.lr.ph, %20
  %24 = phi i32 [ %16, %.lr.ph ], [ %22, %20 ]
  %25 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEv(ptr noundef nonnull align 8 dereferenceable(8) %4) #3
  %26 = 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) #3
  br i1 %26, label %.lr.ph, label %._crit_edge
}

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3maxIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #2

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: EarlyCSEPass,GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass