; LLVM IR from Muhammad-Magdi/problem-solving :: Graphs (Topological ordering)

; 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.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 }

@n = external dso_local global i32, align 4
@m = external dso_local global i32, align 4
@u = external dso_local global i32, align 4
@v = external dso_local global i32, align 4
@adj = external dso_local global [100005 x %"class.std::vector"], align 16
@vis = external dso_local global [100005 x i8], align 16
@_ZSt3cin = external global %"class.std::basic_istream", align 8

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z3DFSi(i32 noundef) #0

; 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 norecurse uwtable
define dso_local noundef i32 @main() #2 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  %4 = call noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext false)
  %5 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) @n)
  %6 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) %5, ptr noundef nonnull align 4 dereferenceable(4) @m)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #4
  store i32 0, ptr %2, align 4, !tbaa !5
  br label %7

7:                                                ; preds = %18, %0
  %8 = load i32, ptr %2, align 4, !tbaa !5
  %9 = load i32, ptr @m, align 4, !tbaa !5
  %10 = icmp slt i32 %8, %9
  br i1 %10, label %12, label %11

11:                                               ; preds = %7
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #4
  br label %21

12:                                               ; preds = %7
  %13 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) @u)
  %14 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) %13, ptr noundef nonnull align 4 dereferenceable(4) @v)
  %15 = load i32, ptr @v, align 4, !tbaa !5
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds [100005 x %"class.std::vector"], ptr @adj, i64 0, i64 %16
  call void @_ZNSt6vectorIiSaIiEE9push_backERKi(ptr noundef nonnull align 8 dereferenceable(24) %17, ptr noundef nonnull align 4 dereferenceable(4) @u)
  br label %18

18:                                               ; preds = %12
  %19 = load i32, ptr %2, align 4, !tbaa !5
  %20 = add nsw i32 %19, 1
  store i32 %20, ptr %2, align 4, !tbaa !5
  br label %7, !llvm.loop !9

21:                                               ; preds = %11
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #4
  store i32 1, ptr %3, align 4, !tbaa !5
  br label %22

22:                                               ; preds = %36, %21
  %23 = load i32, ptr %3, align 4, !tbaa !5
  %24 = load i32, ptr @n, align 4, !tbaa !5
  %25 = icmp sle i32 %23, %24
  br i1 %25, label %27, label %26

26:                                               ; preds = %22
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #4
  br label %39

27:                                               ; preds = %22
  %28 = load i32, ptr %3, align 4, !tbaa !5
  %29 = sext i32 %28 to i64
  %30 = getelementptr inbounds [100005 x i8], ptr @vis, i64 0, i64 %29
  %31 = load i8, ptr %30, align 1, !tbaa !11, !range !13, !noundef !14
  %32 = trunc i8 %31 to i1
  br i1 %32, label %35, label %33

33:                                               ; preds = %27
  %34 = load i32, ptr %3, align 4, !tbaa !5
  call void @_Z3DFSi(i32 noundef %34)
  br label %35

35:                                               ; preds = %33, %27
  br label %36

36:                                               ; preds = %35
  %37 = load i32, ptr %3, align 4, !tbaa !5
  %38 = add nsw i32 %37, 1
  store i32 %38, ptr %3, align 4, !tbaa !5
  br label %22, !llvm.loop !15

39:                                               ; preds = %26
  ret i32 0
}

declare noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext) #3

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) #3

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEE9push_backERKi(ptr noundef nonnull align 8 dereferenceable(24), ptr noundef nonnull align 4 dereferenceable(4)) #0 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 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 #3 = { "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 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = !{!12, !12, i64 0}
!12 = !{!"bool", !7, i64 0}
!13 = !{i8 0, i8 2}
!14 = !{}
!15 = distinct !{!15, !10}


; 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.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 }

@n = external dso_local global i32, align 4
@m = external dso_local global i32, align 4
@u = external dso_local global i32, align 4
@v = external dso_local global i32, align 4
@adj = external dso_local global [100005 x %"class.std::vector"], align 16
@vis = external dso_local local_unnamed_addr global [100005 x i8], align 16
@_ZSt3cin = external global %"class.std::basic_istream", align 8

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z3DFSi(i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #1 {
  %1 = tail call noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext false)
  %2 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) @n)
  %3 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) %2, ptr noundef nonnull align 4 dereferenceable(4) @m)
  %4 = load i32, ptr @m, align 4, !tbaa !5
  %5 = icmp sgt i32 %4, 0
  br i1 %5, label %.lr.ph, label %.preheader

.preheader:                                       ; preds = %.lr.ph, %0
  %6 = load i32, ptr @n, align 4, !tbaa !5
  %.not8 = icmp slt i32 %6, 1
  br i1 %.not8, label %._crit_edge, label %.lr.ph10

.lr.ph:                                           ; preds = %0, %.lr.ph
  %.067 = phi i32 [ %12, %.lr.ph ], [ 0, %0 ]
  %7 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) @u)
  %8 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) %7, ptr noundef nonnull align 4 dereferenceable(4) @v)
  %9 = load i32, ptr @v, align 4, !tbaa !5
  %10 = sext i32 %9 to i64
  %11 = getelementptr inbounds [100005 x %"class.std::vector"], ptr @adj, i64 0, i64 %10
  tail call void @_ZNSt6vectorIiSaIiEE9push_backERKi(ptr noundef nonnull align 8 dereferenceable(24) %11, ptr noundef nonnull align 4 dereferenceable(4) @u)
  %12 = add nuw nsw i32 %.067, 1
  %13 = load i32, ptr @m, align 4, !tbaa !5
  %14 = icmp slt i32 %12, %13
  br i1 %14, label %.lr.ph, label %.preheader, !llvm.loop !9

._crit_edge:                                      ; preds = %21, %.preheader
  ret i32 0

.lr.ph10:                                         ; preds = %.preheader, %21
  %15 = phi i32 [ %22, %21 ], [ %6, %.preheader ]
  %indvars.iv = phi i64 [ %indvars.iv.next, %21 ], [ 1, %.preheader ]
  %16 = getelementptr inbounds [100005 x i8], ptr @vis, i64 0, i64 %indvars.iv
  %17 = load i8, ptr %16, align 1, !tbaa !11, !range !13, !noundef !14
  %18 = trunc nuw i8 %17 to i1
  br i1 %18, label %21, label %19

19:                                               ; preds = %.lr.ph10
  %20 = trunc nuw nsw i64 %indvars.iv to i32
  tail call void @_Z3DFSi(i32 noundef %20)
  %.pre = load i32, ptr @n, align 4, !tbaa !5
  br label %21

21:                                               ; preds = %.lr.ph10, %19
  %22 = phi i32 [ %15, %.lr.ph10 ], [ %.pre, %19 ]
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %23 = sext i32 %22 to i64
  %.not.not = icmp slt i64 %indvars.iv, %23
  br i1 %.not.not, label %.lr.ph10, label %._crit_edge, !llvm.loop !15
}

declare noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext) local_unnamed_addr #2

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #2

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEE9push_backERKi(ptr noundef nonnull align 8 dereferenceable(24), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #0 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 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 #2 = { "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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = !{!12, !12, i64 0}
!12 = !{!"bool", !7, i64 0}
!13 = !{i8 0, i8 2}
!14 = !{}
!15 = distinct !{!15, !10}


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