; LLVM IR from AdarshGaur/Competitive-Programming :: Algorithm Library/Graph Theory/Topological-sort.ll (Z15topologicalSortv)

; 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.0" = type { %"struct.std::_Vector_base.1" }
%"struct.std::_Vector_base.1" = 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 }

@n = external dso_local global i32, align 4
@visited = external dso_local global %"class.std::vector.0", align 8
@ans = external dso_local global %"class.std::vector.0", align 8

; Function Attrs: mustprogress uwtable
declare dso_local noundef zeroext i1 @_Z3dfsi(i32 noundef) #0

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef) #1 align 2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: mustprogress uwtable
define dso_local noundef zeroext i1 @_Z15topologicalSortv() #0 {
  %1 = alloca i1, align 1
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = load i32, ptr @n, align 4, !tbaa !5
  %6 = sext i32 %5 to i64
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #3
  store i32 0, ptr %2, align 4, !tbaa !5
  call void @_ZNSt6vectorIiSaIiEE6resizeEmRKi(ptr noundef nonnull align 8 dereferenceable(24) @visited, i64 noundef %6, ptr noundef nonnull align 4 dereferenceable(4) %2)
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #3
  call void @_ZNSt6vectorIiSaIiEE5clearEv(ptr noundef nonnull align 8 dereferenceable(24) @ans) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #3
  store i32 0, ptr %3, align 4, !tbaa !5
  br label %7

7:                                                ; preds = %24, %0
  %8 = load i32, ptr %3, align 4, !tbaa !5
  %9 = load i32, ptr @n, align 4, !tbaa !5
  %10 = icmp slt i32 %8, %9
  br i1 %10, label %12, label %11

11:                                               ; preds = %7
  store i32 2, ptr %4, align 4
  br label %27

12:                                               ; preds = %7
  %13 = load i32, ptr %3, align 4, !tbaa !5
  %14 = sext i32 %13 to i64
  %15 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) @visited, i64 noundef %14) #3
  %16 = load i32, ptr %15, align 4, !tbaa !5
  %17 = icmp ne i32 %16, 0
  br i1 %17, label %23, label %18

18:                                               ; preds = %12
  %19 = load i32, ptr %3, align 4, !tbaa !5
  %20 = call noundef zeroext i1 @_Z3dfsi(i32 noundef %19)
  br i1 %20, label %22, label %21

21:                                               ; preds = %18
  store i1 false, ptr %1, align 1
  store i32 1, ptr %4, align 4
  br label %27

22:                                               ; preds = %18
  br label %23

23:                                               ; preds = %22, %12
  br label %24

24:                                               ; preds = %23
  %25 = load i32, ptr %3, align 4, !tbaa !5
  %26 = add nsw i32 %25, 1
  store i32 %26, ptr %3, align 4, !tbaa !5
  br label %7, !llvm.loop !9

27:                                               ; preds = %21, %11
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  %28 = load i32, ptr %4, align 4
  switch i32 %28, label %32 [
    i32 2, label %29
    i32 1, label %30
  ]

29:                                               ; preds = %27
  store i1 true, ptr %1, align 1
  br label %30

30:                                               ; preds = %29, %27
  %31 = load i1, ptr %1, align 1
  ret i1 %31

32:                                               ; preds = %27
  unreachable
}

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEE6resizeEmRKi(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef, ptr noundef nonnull align 4 dereferenceable(4)) #0 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEE5clearEv(ptr noundef nonnull align 8 dereferenceable(24)) #1 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 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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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 = distinct !{!9, !10}
!10 = !{!"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.0" = type { %"struct.std::_Vector_base.1" }
%"struct.std::_Vector_base.1" = 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 }

@n = external dso_local local_unnamed_addr global i32, align 4
@visited = external dso_local global %"class.std::vector.0", align 8
@ans = external dso_local global %"class.std::vector.0", align 8

; Function Attrs: mustprogress uwtable
declare dso_local noundef zeroext i1 @_Z3dfsi(i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef) local_unnamed_addr #1 align 2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: mustprogress uwtable
define dso_local noundef zeroext i1 @_Z15topologicalSortv() local_unnamed_addr #0 {
  %1 = alloca i32, align 4
  %2 = load i32, ptr @n, align 4, !tbaa !5
  %3 = sext i32 %2 to i64
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #3
  store i32 0, ptr %1, align 4, !tbaa !5
  call void @_ZNSt6vectorIiSaIiEE6resizeEmRKi(ptr noundef nonnull align 8 dereferenceable(24) @visited, i64 noundef %3, ptr noundef nonnull align 4 dereferenceable(4) %1)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #3
  call void @_ZNSt6vectorIiSaIiEE5clearEv(ptr noundef nonnull align 8 dereferenceable(24) @ans) #3
  %4 = load i32, ptr @n, align 4, !tbaa !5
  %5 = icmp slt i32 %4, 1
  br i1 %5, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %0, %11
  %indvars.iv = phi i64 [ %indvars.iv.next, %11 ], [ 0, %0 ]
  %6 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) @visited, i64 noundef %indvars.iv) #3
  %7 = load i32, ptr %6, align 4, !tbaa !5
  %.not = icmp eq i32 %7, 0
  br i1 %.not, label %8, label %11

8:                                                ; preds = %.lr.ph
  %9 = trunc nuw nsw i64 %indvars.iv to i32
  %10 = call noundef zeroext i1 @_Z3dfsi(i32 noundef %9)
  br i1 %10, label %11, label %._crit_edge

11:                                               ; preds = %.lr.ph, %8
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %12 = load i32, ptr @n, align 4, !tbaa !5
  %13 = sext i32 %12 to i64
  %.not10 = icmp slt i64 %indvars.iv.next, %13
  br i1 %.not10, label %.lr.ph, label %._crit_edge, !llvm.loop !9

._crit_edge:                                      ; preds = %11, %8, %0
  %.lcssa = phi i1 [ true, %0 ], [ false, %8 ], [ true, %11 ]
  ret i1 %.lcssa
}

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEE6resizeEmRKi(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef, ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEE5clearEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #1 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 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 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


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