; LLVM IR from Dev-XYS/Algorithms :: Lowest-Common-Ancestor(Doubling).ll (Z3DFSiii)

; 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.vertex = type { i32, i32 }
%struct.edge = type { i32, i32 }

@V = external dso_local global [100010 x %struct.vertex], align 16
@E = external dso_local global [200010 x %struct.edge], align 16
@fa = external dso_local global [100010 x [25 x i32]], align 16

; Function Attrs: mustprogress uwtable
define dso_local void @_Z3DFSiii(i32 noundef %0, i32 noundef %1, i32 noundef %2) #0 {
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store i32 %0, ptr %4, align 4, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !5
  store i32 %2, ptr %6, align 4, !tbaa !5
  %8 = load i32, ptr %4, align 4, !tbaa !5
  %9 = sext i32 %8 to i64
  %10 = getelementptr inbounds [100010 x [25 x i32]], ptr @fa, i64 0, i64 %9
  %11 = getelementptr inbounds [25 x i32], ptr %10, i64 0, i64 0
  %12 = load i32, ptr %11, align 4, !tbaa !5
  %13 = icmp eq i32 %12, 0
  br i1 %13, label %14, label %50

14:                                               ; preds = %3
  %15 = load i32, ptr %5, align 4, !tbaa !5
  %16 = load i32, ptr %4, align 4, !tbaa !5
  %17 = sext i32 %16 to i64
  %18 = getelementptr inbounds [100010 x [25 x i32]], ptr @fa, i64 0, i64 %17
  %19 = getelementptr inbounds [25 x i32], ptr %18, i64 0, i64 0
  store i32 %15, ptr %19, align 4, !tbaa !5
  %20 = load i32, ptr %6, align 4, !tbaa !5
  %21 = load i32, ptr %4, align 4, !tbaa !5
  %22 = sext i32 %21 to i64
  %23 = getelementptr inbounds [100010 x %struct.vertex], ptr @V, i64 0, i64 %22
  %24 = getelementptr inbounds %struct.vertex, ptr %23, i32 0, i32 1
  store i32 %20, ptr %24, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  %25 = load i32, ptr %4, align 4, !tbaa !5
  %26 = sext i32 %25 to i64
  %27 = getelementptr inbounds [100010 x %struct.vertex], ptr @V, i64 0, i64 %26
  %28 = getelementptr inbounds %struct.vertex, ptr %27, i32 0, i32 0
  %29 = load i32, ptr %28, align 8, !tbaa !11
  store i32 %29, ptr %7, align 4, !tbaa !5
  br label %30

30:                                               ; preds = %43, %14
  %31 = load i32, ptr %7, align 4, !tbaa !5
  %32 = icmp ne i32 %31, 0
  br i1 %32, label %34, label %33

33:                                               ; preds = %30
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  br label %49

34:                                               ; preds = %30
  %35 = load i32, ptr %7, align 4, !tbaa !5
  %36 = sext i32 %35 to i64
  %37 = getelementptr inbounds [200010 x %struct.edge], ptr @E, i64 0, i64 %36
  %38 = getelementptr inbounds %struct.edge, ptr %37, i32 0, i32 0
  %39 = load i32, ptr %38, align 8, !tbaa !12
  %40 = load i32, ptr %4, align 4, !tbaa !5
  %41 = load i32, ptr %6, align 4, !tbaa !5
  %42 = add nsw i32 %41, 1
  call void @_Z3DFSiii(i32 noundef %39, i32 noundef %40, i32 noundef %42)
  br label %43

43:                                               ; preds = %34
  %44 = load i32, ptr %7, align 4, !tbaa !5
  %45 = sext i32 %44 to i64
  %46 = getelementptr inbounds [200010 x %struct.edge], ptr @E, i64 0, i64 %45
  %47 = getelementptr inbounds %struct.edge, ptr %46, i32 0, i32 1
  %48 = load i32, ptr %47, align 4, !tbaa !14
  store i32 %48, ptr %7, align 4, !tbaa !5
  br label %30, !llvm.loop !15

49:                                               ; preds = %33
  br label %50

50:                                               ; preds = %49, %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: 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 = { 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 4}
!10 = !{!"_ZTS6vertex", !6, i64 0, !6, i64 4}
!11 = !{!10, !6, i64 0}
!12 = !{!13, !6, i64 0}
!13 = !{!"_ZTS4edge", !6, i64 0, !6, i64 4}
!14 = !{!13, !6, i64 4}
!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"

%struct.vertex = type { i32, i32 }
%struct.edge = type { i32, i32 }

@V = external dso_local local_unnamed_addr global [100010 x %struct.vertex], align 16
@E = external dso_local local_unnamed_addr global [200010 x %struct.edge], align 16
@fa = external dso_local local_unnamed_addr global [100010 x [25 x i32]], align 16

; Function Attrs: mustprogress nofree nosync nounwind memory(readwrite, argmem: none, inaccessiblemem: none) uwtable
define dso_local void @_Z3DFSiii(i32 noundef %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %4 = sext i32 %0 to i64
  %5 = getelementptr inbounds [100010 x [25 x i32]], ptr @fa, i64 0, i64 %4
  %6 = load i32, ptr %5, align 4, !tbaa !5
  %7 = icmp eq i32 %6, 0
  br i1 %7, label %8, label %.loopexit

8:                                                ; preds = %3
  store i32 %1, ptr %5, align 4, !tbaa !5
  %9 = getelementptr inbounds [100010 x %struct.vertex], ptr @V, i64 0, i64 %4
  %10 = getelementptr inbounds i8, ptr %9, i64 4
  store i32 %2, ptr %10, align 4, !tbaa !9
  %.011 = load i32, ptr %9, align 8, !tbaa !5
  %.not12 = icmp eq i32 %.011, 0
  br i1 %.not12, label %.loopexit, label %.lr.ph

.lr.ph:                                           ; preds = %8
  %11 = add nsw i32 %2, 1
  br label %12

12:                                               ; preds = %.lr.ph, %12
  %.013 = phi i32 [ %.011, %.lr.ph ], [ %.0, %12 ]
  %13 = sext i32 %.013 to i64
  %14 = getelementptr inbounds [200010 x %struct.edge], ptr @E, i64 0, i64 %13
  %15 = load i32, ptr %14, align 8, !tbaa !11
  tail call void @_Z3DFSiii(i32 noundef %15, i32 noundef %0, i32 noundef %11)
  %16 = getelementptr inbounds i8, ptr %14, i64 4
  %.0 = load i32, ptr %16, align 4, !tbaa !5
  %.not = icmp eq i32 %.0, 0
  br i1 %.not, label %.loopexit, label %12, !llvm.loop !13

.loopexit:                                        ; preds = %12, %8, %3
  ret void
}

attributes #0 = { mustprogress nofree nosync nounwind memory(readwrite, argmem: none, inaccessiblemem: none) 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 4}
!10 = !{!"_ZTS6vertex", !6, i64 0, !6, i64 4}
!11 = !{!12, !6, i64 0}
!12 = !{!"_ZTS4edge", !6, i64 0, !6, i64 4}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}


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