; LLVM IR from sbshah97/DS-Algo-Handbook :: labs/lab4/dfs_count.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 }

@adj = external dso_local global [10 x %"class.std::vector"], align 16
@visited = external dso_local global [10 x i8], align 1
@num = external dso_local global i32, align 4

; Function Attrs: mustprogress uwtable
define dso_local void @_Z3dfsi(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  store i32 %0, ptr %2, align 4, !tbaa !5
  %4 = load i32, ptr %2, align 4, !tbaa !5
  %5 = sext i32 %4 to i64
  %6 = getelementptr inbounds [10 x i8], ptr @visited, i64 0, i64 %5
  store i8 1, ptr %6, align 1, !tbaa !9
  %7 = load i32, ptr @num, align 4, !tbaa !5
  %8 = add nsw i32 %7, 1
  store i32 %8, ptr @num, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #3
  store i32 0, ptr %3, align 4, !tbaa !5
  br label %9

9:                                                ; preds = %41, %1
  %10 = load i32, ptr %3, align 4, !tbaa !5
  %11 = sext i32 %10 to i64
  %12 = load i32, ptr %2, align 4, !tbaa !5
  %13 = sext i32 %12 to i64
  %14 = getelementptr inbounds [10 x %"class.std::vector"], ptr @adj, i64 0, i64 %13
  %15 = call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %14) #3
  %16 = icmp ult i64 %11, %15
  br i1 %16, label %18, label %17

17:                                               ; preds = %9
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  br label %44

18:                                               ; preds = %9
  %19 = load i32, ptr %2, align 4, !tbaa !5
  %20 = sext i32 %19 to i64
  %21 = getelementptr inbounds [10 x %"class.std::vector"], ptr @adj, i64 0, i64 %20
  %22 = load i32, ptr %3, align 4, !tbaa !5
  %23 = sext i32 %22 to i64
  %24 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %21, i64 noundef %23) #3
  %25 = load i32, ptr %24, align 4, !tbaa !5
  %26 = sext i32 %25 to i64
  %27 = getelementptr inbounds [10 x i8], ptr @visited, i64 0, i64 %26
  %28 = load i8, ptr %27, align 1, !tbaa !9, !range !11, !noundef !12
  %29 = trunc i8 %28 to i1
  %30 = zext i1 %29 to i32
  %31 = icmp eq i32 %30, 0
  br i1 %31, label %32, label %40

32:                                               ; preds = %18
  %33 = load i32, ptr %2, align 4, !tbaa !5
  %34 = sext i32 %33 to i64
  %35 = getelementptr inbounds [10 x %"class.std::vector"], ptr @adj, i64 0, i64 %34
  %36 = load i32, ptr %3, align 4, !tbaa !5
  %37 = sext i32 %36 to i64
  %38 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %35, i64 noundef %37) #3
  %39 = load i32, ptr %38, align 4, !tbaa !5
  call void @_Z3dfsi(i32 noundef %39)
  br label %40

40:                                               ; preds = %32, %18
  br label %41

41:                                               ; preds = %40
  %42 = load i32, ptr %3, align 4, !tbaa !5
  %43 = add nsw i32 %42, 1
  store i32 %43, ptr %3, align 4, !tbaa !5
  br label %9, !llvm.loop !13

44:                                               ; preds = %17
  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 = !{!"bool", !7, i64 0}
!11 = !{i8 0, i8 2}
!12 = !{}
!13 = distinct !{!13, !14}
!14 = !{!"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 }

@adj = external dso_local global [10 x %"class.std::vector"], align 16
@visited = external dso_local local_unnamed_addr global [10 x i8], align 1
@num = external dso_local local_unnamed_addr global i32, align 4

; 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 [10 x i8], ptr @visited, i64 0, i64 %2
  store i8 1, ptr %3, align 1, !tbaa !5
  %4 = load i32, ptr @num, align 4, !tbaa !9
  %5 = add nsw i32 %4, 1
  store i32 %5, ptr @num, align 4, !tbaa !9
  %6 = getelementptr inbounds [10 x %"class.std::vector"], ptr @adj, i64 0, i64 %2
  %7 = tail call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %6) #1
  %.not = icmp eq i64 %7, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %17, %1
  ret void

.lr.ph:                                           ; preds = %1, %17
  %indvars.iv = phi i64 [ %indvars.iv.next, %17 ], [ 0, %1 ]
  %8 = tail call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %6, i64 noundef %indvars.iv) #1
  %9 = load i32, ptr %8, align 4, !tbaa !9
  %10 = sext i32 %9 to i64
  %11 = getelementptr inbounds [10 x i8], ptr @visited, i64 0, i64 %10
  %12 = load i8, ptr %11, align 1, !tbaa !5, !range !11, !noundef !12
  %13 = icmp eq i8 %12, 0
  br i1 %13, label %14, label %17

14:                                               ; preds = %.lr.ph
  %15 = tail call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %6, i64 noundef %indvars.iv) #1
  %16 = load i32, ptr %15, align 4, !tbaa !9
  tail call void @_Z3dfsi(i32 noundef %16)
  br label %17

17:                                               ; preds = %.lr.ph, %14
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %18 = tail call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %6) #1
  %19 = icmp ugt i64 %18, %indvars.iv.next
  br i1 %19, 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 = !{!"bool", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{i8 0, i8 2}
!12 = !{}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}


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