; LLVM IR from tangjz/acm-icpc :: lydsy/1574.ll (Z3dfsi)

; 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 }

@G = external dso_local global [30001 x %"class.std::vector"], align 16
@cnt = external dso_local global i32, align 4
@visited = external dso_local global [30001 x i8], align 16

; Function Attrs: mustprogress uwtable
define dso_local void @_Z3dfsi(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca i64, align 8
  %4 = alloca i32, align 4
  store i32 %0, ptr %2, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #3
  store i64 0, ptr %3, align 8, !tbaa !9
  br label %5

5:                                                ; preds = %33, %1
  %6 = load i64, ptr %3, align 8, !tbaa !9
  %7 = load i32, ptr %2, align 4, !tbaa !5
  %8 = sext i32 %7 to i64
  %9 = getelementptr inbounds [30001 x %"class.std::vector"], ptr @G, i64 0, i64 %8
  %10 = call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %9) #3
  %11 = icmp ult i64 %6, %10
  br i1 %11, label %13, label %12

12:                                               ; preds = %5
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #3
  br label %36

13:                                               ; preds = %5
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  %14 = load i32, ptr %2, align 4, !tbaa !5
  %15 = sext i32 %14 to i64
  %16 = getelementptr inbounds [30001 x %"class.std::vector"], ptr @G, i64 0, i64 %15
  %17 = load i64, ptr %3, align 8, !tbaa !9
  %18 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %16, i64 noundef %17) #3
  %19 = load i32, ptr %18, align 4, !tbaa !5
  store i32 %19, ptr %4, align 4, !tbaa !5
  %20 = load i32, ptr %4, align 4, !tbaa !5
  %21 = sext i32 %20 to i64
  %22 = getelementptr inbounds [30001 x i8], ptr @visited, i64 0, i64 %21
  %23 = load i8, ptr %22, align 1, !tbaa !11, !range !13, !noundef !14
  %24 = trunc i8 %23 to i1
  br i1 %24, label %32, label %25

25:                                               ; preds = %13
  %26 = load i32, ptr @cnt, align 4, !tbaa !5
  %27 = add nsw i32 %26, 1
  store i32 %27, ptr @cnt, align 4, !tbaa !5
  %28 = load i32, ptr %4, align 4, !tbaa !5
  %29 = sext i32 %28 to i64
  %30 = getelementptr inbounds [30001 x i8], ptr @visited, i64 0, i64 %29
  store i8 1, ptr %30, align 1, !tbaa !11
  %31 = load i32, ptr %4, align 4, !tbaa !5
  call void @_Z3dfsi(i32 noundef %31)
  br label %32

32:                                               ; preds = %25, %13
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  br label %33

33:                                               ; preds = %32
  %34 = load i64, ptr %3, align 8, !tbaa !9
  %35 = add i64 %34, 1
  store i64 %35, ptr %3, align 8, !tbaa !9
  br label %5, !llvm.loop !15

36:                                               ; preds = %12
  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 noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24)) #2 align 2

; 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) #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 = { 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 = !{!"long", !7, i64 0}
!11 = !{!12, !12, i64 0}
!12 = !{!"bool", !7, i64 0}
!13 = !{i8 0, i8 2}
!14 = !{}
!15 = distinct !{!15, !16}
!16 = !{!"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<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 }

@G = external dso_local global [30001 x %"class.std::vector"], align 16
@cnt = external dso_local local_unnamed_addr global i32, align 4
@visited = external dso_local local_unnamed_addr global [30001 x i8], align 16

; Function Attrs: mustprogress nounwind uwtable
define dso_local void @_Z3dfsi(i32 noundef %0) local_unnamed_addr #0 {
  %2 = sext i32 %0 to i64
  %3 = getelementptr inbounds [30001 x %"class.std::vector"], ptr @G, i64 0, i64 %2
  %4 = tail call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %3) #1
  %.not = icmp eq i64 %4, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %14, %1
  ret void

.lr.ph:                                           ; preds = %1, %14
  %.08 = phi i64 [ %15, %14 ], [ 0, %1 ]
  %5 = tail call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %3, i64 noundef %.08) #1
  %6 = load i32, ptr %5, align 4, !tbaa !5
  %7 = sext i32 %6 to i64
  %8 = getelementptr inbounds [30001 x i8], ptr @visited, i64 0, i64 %7
  %9 = load i8, ptr %8, align 1, !tbaa !9, !range !11, !noundef !12
  %10 = trunc nuw i8 %9 to i1
  br i1 %10, label %14, label %11

11:                                               ; preds = %.lr.ph
  %12 = load i32, ptr @cnt, align 4, !tbaa !5
  %13 = add nsw i32 %12, 1
  store i32 %13, ptr @cnt, align 4, !tbaa !5
  store i8 1, ptr %8, align 1, !tbaa !9
  tail call void @_Z3dfsi(i32 noundef %6)
  br label %14

14:                                               ; preds = %11, %.lr.ph
  %15 = add nuw i64 %.08, 1
  %16 = tail call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %3) #1
  %17 = icmp ult i64 %15, %16
  br i1 %17, label %.lr.ph, label %._crit_edge, !llvm.loop !13
}

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #0 align 2

; 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 #0 align 2

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 = { 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 = !{!"bool", !7, i64 0}
!11 = !{i8 0, i8 2}
!12 = !{}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}


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