; LLVM IR from imteekay/algorithms :: competitive-programming/uva (280-vertex)

; 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"

%"struct.std::pair" = type <{ %"struct.std::_Rb_tree_const_iterator", i8, [7 x i8] }>
%"struct.std::_Rb_tree_const_iterator" = type { ptr }

@VISITED = external dso_local global i32, align 4
@UNVISITED = external dso_local global i32, align 4

; Function Attrs: mustprogress uwtable
define dso_local void @_Z3dfsiRSt6vectorIS_IiSaIiEESaIS1_EERSt3setIiSt4lessIiES0_EPi(i32 noundef %0, ptr noundef nonnull align 8 dereferenceable(24) %1, ptr noundef nonnull align 8 dereferenceable(48) %2, ptr noundef %3) #0 {
  %5 = alloca i32, align 4
  %6 = alloca ptr, align 8
  %7 = alloca ptr, align 8
  %8 = alloca ptr, align 8
  %9 = alloca i32, align 4
  %10 = alloca i32, align 4
  %11 = alloca %"struct.std::pair", align 8
  store i32 %0, ptr %5, align 4, !tbaa !5
  store ptr %1, ptr %6, align 8, !tbaa !9
  store ptr %2, ptr %7, align 8, !tbaa !9
  store ptr %3, ptr %8, align 8, !tbaa !9
  %12 = load i32, ptr @VISITED, align 4, !tbaa !5
  %13 = load ptr, ptr %8, align 8, !tbaa !9
  %14 = load i32, ptr %5, align 4, !tbaa !5
  %15 = sext i32 %14 to i64
  %16 = getelementptr inbounds i32, ptr %13, i64 %15
  store i32 %12, ptr %16, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %9) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %10) #3
  store i32 0, ptr %10, align 4, !tbaa !5
  br label %17

17:                                               ; preds = %55, %4
  %18 = load i32, ptr %10, align 4, !tbaa !5
  %19 = sext i32 %18 to i64
  %20 = load ptr, ptr %6, align 8, !tbaa !9
  %21 = load i32, ptr %5, align 4, !tbaa !5
  %22 = sext i32 %21 to i64
  %23 = call noundef nonnull align 8 dereferenceable(24) ptr @_ZNSt6vectorIS_IiSaIiEESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) %20, i64 noundef %22) #3
  %24 = call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %23) #3
  %25 = icmp ult i64 %19, %24
  br i1 %25, label %27, label %26

26:                                               ; preds = %17
  call void @llvm.lifetime.end.p0(i64 4, ptr %10) #3
  br label %58

27:                                               ; preds = %17
  %28 = load ptr, ptr %6, align 8, !tbaa !9
  %29 = load i32, ptr %5, align 4, !tbaa !5
  %30 = sext i32 %29 to i64
  %31 = call noundef nonnull align 8 dereferenceable(24) ptr @_ZNSt6vectorIS_IiSaIiEESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) %28, i64 noundef %30) #3
  %32 = load i32, ptr %10, align 4, !tbaa !5
  %33 = sext i32 %32 to i64
  %34 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %31, i64 noundef %33) #3
  %35 = load i32, ptr %34, align 4, !tbaa !5
  store i32 %35, ptr %9, align 4, !tbaa !5
  %36 = load ptr, ptr %7, align 8, !tbaa !9
  %37 = call { ptr, i8 } @_ZNSt3setIiSt4lessIiESaIiEE6insertERKi(ptr noundef nonnull align 8 dereferenceable(48) %36, ptr noundef nonnull align 4 dereferenceable(4) %9)
  %38 = getelementptr inbounds { ptr, i8 }, ptr %11, i32 0, i32 0
  %39 = extractvalue { ptr, i8 } %37, 0
  store ptr %39, ptr %38, align 8
  %40 = getelementptr inbounds { ptr, i8 }, ptr %11, i32 0, i32 1
  %41 = extractvalue { ptr, i8 } %37, 1
  store i8 %41, ptr %40, align 8
  %42 = load ptr, ptr %8, align 8, !tbaa !9
  %43 = load i32, ptr %9, align 4, !tbaa !5
  %44 = sext i32 %43 to i64
  %45 = getelementptr inbounds i32, ptr %42, i64 %44
  %46 = load i32, ptr %45, align 4, !tbaa !5
  %47 = load i32, ptr @UNVISITED, align 4, !tbaa !5
  %48 = icmp eq i32 %46, %47
  br i1 %48, label %49, label %54

49:                                               ; preds = %27
  %50 = load i32, ptr %9, align 4, !tbaa !5
  %51 = load ptr, ptr %6, align 8, !tbaa !9
  %52 = load ptr, ptr %7, align 8, !tbaa !9
  %53 = load ptr, ptr %8, align 8, !tbaa !9
  call void @_Z3dfsiRSt6vectorIS_IiSaIiEESaIS1_EERSt3setIiSt4lessIiES0_EPi(i32 noundef %50, ptr noundef nonnull align 8 dereferenceable(24) %51, ptr noundef nonnull align 8 dereferenceable(48) %52, ptr noundef %53)
  br label %54

54:                                               ; preds = %49, %27
  br label %55

55:                                               ; preds = %54
  %56 = load i32, ptr %10, align 4, !tbaa !5
  %57 = add nsw i32 %56, 1
  store i32 %57, ptr %10, align 4, !tbaa !5
  br label %17, !llvm.loop !11

58:                                               ; preds = %26
  call void @llvm.lifetime.end.p0(i64 4, ptr %9) #3
  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 nonnull align 8 dereferenceable(24) ptr @_ZNSt6vectorIS_IiSaIiEESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef) #2 align 2

; 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: mustprogress uwtable
declare dso_local { ptr, i8 } @_ZNSt3setIiSt4lessIiESaIiEE6insertERKi(ptr noundef nonnull align 8 dereferenceable(48), ptr noundef nonnull align 4 dereferenceable(4)) #0 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 = !{!"any pointer", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"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"

@VISITED = external dso_local local_unnamed_addr global i32, align 4
@UNVISITED = external dso_local local_unnamed_addr global i32, align 4

; Function Attrs: mustprogress uwtable
define dso_local void @_Z3dfsiRSt6vectorIS_IiSaIiEESaIS1_EERSt3setIiSt4lessIiES0_EPi(i32 noundef %0, ptr noundef nonnull align 8 dereferenceable(24) %1, ptr noundef nonnull align 8 dereferenceable(48) %2, ptr nocapture noundef %3) local_unnamed_addr #0 {
  %5 = alloca i32, align 4
  %6 = load i32, ptr @VISITED, align 4, !tbaa !5
  %7 = sext i32 %0 to i64
  %8 = getelementptr inbounds i32, ptr %3, i64 %7
  store i32 %6, ptr %8, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %5) #3
  %9 = tail call noundef nonnull align 8 dereferenceable(24) ptr @_ZNSt6vectorIS_IiSaIiEESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) %1, i64 noundef %7) #3
  %10 = tail call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %9) #3
  %.not = icmp eq i64 %10, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %22, %4
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %5) #3
  ret void

.lr.ph:                                           ; preds = %4, %22
  %indvars.iv = phi i64 [ %indvars.iv.next, %22 ], [ 0, %4 ]
  %11 = call noundef nonnull align 8 dereferenceable(24) ptr @_ZNSt6vectorIS_IiSaIiEESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) %1, i64 noundef %7) #3
  %12 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %11, i64 noundef %indvars.iv) #3
  %13 = load i32, ptr %12, align 4, !tbaa !5
  store i32 %13, ptr %5, align 4, !tbaa !5
  %14 = call { ptr, i8 } @_ZNSt3setIiSt4lessIiESaIiEE6insertERKi(ptr noundef nonnull align 8 dereferenceable(48) %2, ptr noundef nonnull align 4 dereferenceable(4) %5)
  %15 = load i32, ptr %5, align 4, !tbaa !5
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds i32, ptr %3, i64 %16
  %18 = load i32, ptr %17, align 4, !tbaa !5
  %19 = load i32, ptr @UNVISITED, align 4, !tbaa !5
  %20 = icmp eq i32 %18, %19
  br i1 %20, label %21, label %22

21:                                               ; preds = %.lr.ph
  call void @_Z3dfsiRSt6vectorIS_IiSaIiEESaIS1_EERSt3setIiSt4lessIiES0_EPi(i32 noundef %15, ptr noundef nonnull align 8 dereferenceable(24) %1, ptr noundef nonnull align 8 dereferenceable(48) %2, ptr noundef nonnull %3)
  br label %22

22:                                               ; preds = %.lr.ph, %21
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %23 = call noundef nonnull align 8 dereferenceable(24) ptr @_ZNSt6vectorIS_IiSaIiEESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) %1, i64 noundef %7) #3
  %24 = call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %23) #3
  %25 = icmp ugt i64 %24, %indvars.iv.next
  br i1 %25, label %.lr.ph, label %._crit_edge, !llvm.loop !9
}

; Function Attrs: mustprogress 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 nonnull align 8 dereferenceable(24) ptr @_ZNSt6vectorIS_IiSaIiEESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef) local_unnamed_addr #2 align 2

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

; Function Attrs: mustprogress uwtable
declare dso_local { ptr, i8 } @_ZNSt3setIiSt4lessIiESaIiEE6insertERKi(ptr noundef nonnull align 8 dereferenceable(48), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress 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 = { mustprogress 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 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


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