; LLVM IR from tangjz/acm-icpc :: 51nod/1967.ll (Z3dfsii)

; 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.Node = type { i32, i32, i32, i32 }

@p = external dso_local global [100005 x i32], align 16
@ans = external dso_local global [400005 x i32], align 16
@e = external dso_local global [800011 x %struct.Node], align 16
@dir = external dso_local global [400005 x i8], align 16

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_Z3delii(i32 noundef, i32 noundef) #1

; Function Attrs: mustprogress uwtable
define dso_local void @_Z3dfsii(i32 noundef %0, i32 noundef %1) #2 {
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #3
  %7 = load i32, ptr %3, align 4, !tbaa !5
  %8 = sext i32 %7 to i64
  %9 = getelementptr inbounds [100005 x i32], ptr @p, i64 0, i64 %8
  %10 = load i32, ptr %9, align 4, !tbaa !5
  store i32 %10, ptr %5, align 4, !tbaa !5
  br label %11

11:                                               ; preds = %28, %2
  %12 = load i32, ptr %5, align 4, !tbaa !5
  %13 = icmp ne i32 %12, -1
  br i1 %13, label %15, label %14

14:                                               ; preds = %11
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #3
  br label %33

15:                                               ; preds = %11
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #3
  %16 = load i32, ptr %5, align 4, !tbaa !5
  %17 = sext i32 %16 to i64
  %18 = getelementptr inbounds [800011 x %struct.Node], ptr @e, i64 0, i64 %17
  %19 = getelementptr inbounds %struct.Node, ptr %18, i32 0, i32 2
  %20 = load i32, ptr %19, align 8, !tbaa !9
  store i32 %20, ptr %6, align 4, !tbaa !5
  %21 = load i32, ptr %3, align 4, !tbaa !5
  %22 = load i32, ptr %5, align 4, !tbaa !5
  call void @_Z3delii(i32 noundef %21, i32 noundef %22)
  %23 = load i32, ptr %6, align 4, !tbaa !5
  %24 = load i32, ptr %5, align 4, !tbaa !5
  %25 = xor i32 %24, 1
  call void @_Z3delii(i32 noundef %23, i32 noundef %25)
  %26 = load i32, ptr %6, align 4, !tbaa !5
  %27 = load i32, ptr %5, align 4, !tbaa !5
  call void @_Z3dfsii(i32 noundef %26, i32 noundef %27)
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #3
  br label %28

28:                                               ; preds = %15
  %29 = load i32, ptr %3, align 4, !tbaa !5
  %30 = sext i32 %29 to i64
  %31 = getelementptr inbounds [100005 x i32], ptr @p, i64 0, i64 %30
  %32 = load i32, ptr %31, align 4, !tbaa !5
  store i32 %32, ptr %5, align 4, !tbaa !5
  br label %11, !llvm.loop !11

33:                                               ; preds = %14
  %34 = load i32, ptr %4, align 4, !tbaa !5
  %35 = icmp ne i32 %34, -1
  br i1 %35, label %36, label %45

36:                                               ; preds = %33
  %37 = load i32, ptr %4, align 4, !tbaa !5
  %38 = and i32 %37, 1
  %39 = icmp ne i32 %38, 0
  %40 = load i32, ptr %4, align 4, !tbaa !5
  %41 = ashr i32 %40, 1
  %42 = sext i32 %41 to i64
  %43 = getelementptr inbounds [400005 x i8], ptr @dir, i64 0, i64 %42
  %44 = zext i1 %39 to i8
  store i8 %44, ptr %43, align 1, !tbaa !13
  br label %45

45:                                               ; preds = %36, %33
  %46 = load i32, ptr %4, align 4, !tbaa !5
  %47 = load i32, ptr @ans, align 16, !tbaa !5
  %48 = add nsw i32 %47, 1
  store i32 %48, ptr @ans, align 16, !tbaa !5
  %49 = sext i32 %48 to i64
  %50 = getelementptr inbounds [400005 x i32], ptr @ans, i64 0, i64 %49
  store i32 %46, ptr %50, align 4, !tbaa !5
  ret void
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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 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, !6, i64 8}
!10 = !{!"_ZTS4Node", !6, i64 0, !6, i64 4, !6, i64 8, !6, i64 12}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = !{!14, !14, i64 0}
!14 = !{!"bool", !7, i64 0}


; 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"

%struct.Node = type { i32, i32, i32, i32 }

@p = external dso_local local_unnamed_addr global [100005 x i32], align 16
@ans = external dso_local local_unnamed_addr global [400005 x i32], align 16
@e = external dso_local local_unnamed_addr global [800011 x %struct.Node], align 16
@dir = external dso_local local_unnamed_addr global [400005 x i8], align 16

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_Z3delii(i32 noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local void @_Z3dfsii(i32 noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = sext i32 %0 to i64
  %4 = getelementptr inbounds [100005 x i32], ptr @p, i64 0, i64 %3
  %.016 = load i32, ptr %4, align 4, !tbaa !5
  %.not17 = icmp eq i32 %.016, -1
  br i1 %.not17, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %.lr.ph, %2
  %.not15 = icmp eq i32 %1, -1
  br i1 %.not15, label %15, label %9

.lr.ph:                                           ; preds = %2, %.lr.ph
  %.018 = phi i32 [ %.0, %.lr.ph ], [ %.016, %2 ]
  %5 = sext i32 %.018 to i64
  %6 = getelementptr inbounds [800011 x %struct.Node], ptr @e, i64 0, i64 %5, i32 2
  %7 = load i32, ptr %6, align 8, !tbaa !9
  tail call void @_Z3delii(i32 noundef %0, i32 noundef %.018)
  %8 = xor i32 %.018, 1
  tail call void @_Z3delii(i32 noundef %7, i32 noundef %8)
  tail call void @_Z3dfsii(i32 noundef %7, i32 noundef %.018)
  %.0 = load i32, ptr %4, align 4, !tbaa !5
  %.not = icmp eq i32 %.0, -1
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !11

9:                                                ; preds = %._crit_edge
  %10 = ashr i32 %1, 1
  %11 = sext i32 %10 to i64
  %12 = getelementptr inbounds [400005 x i8], ptr @dir, i64 0, i64 %11
  %13 = trunc i32 %1 to i8
  %14 = and i8 %13, 1
  store i8 %14, ptr %12, align 1, !tbaa !13
  br label %15

15:                                               ; preds = %9, %._crit_edge
  %16 = load i32, ptr @ans, align 16, !tbaa !5
  %17 = add nsw i32 %16, 1
  store i32 %17, ptr @ans, align 16, !tbaa !5
  %18 = sext i32 %17 to i64
  %19 = getelementptr inbounds [400005 x i32], ptr @ans, i64 0, i64 %18
  store i32 %1, ptr %19, align 4, !tbaa !5
  ret void
}

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" }

!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, !6, i64 8}
!10 = !{!"_ZTS4Node", !6, i64 0, !6, i64 4, !6, i64 8, !6, i64 12}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = !{!14, !14, i64 0}
!14 = !{!"bool", !7, i64 0}


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