; LLVM IR from codemistic/Data-Structures-and-Algorithms :: CPP/LINKED LIST/ALGORITHMIC PROBLEMS RELATED TO LINKEDLIST/find_begeningof_circle._928c1988 (cycleRP4node)

; 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.node = type { i32, ptr }

; 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
define dso_local noundef ptr @_Z11floyd_cycleRP4node(ptr noundef nonnull align 8 dereferenceable(8) %0) #1 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca ptr, align 8
  %7 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  %8 = load ptr, ptr %3, align 8, !tbaa !5
  %9 = load ptr, ptr %8, align 8, !tbaa !5
  %10 = icmp eq ptr %9, null
  br i1 %10, label %11, label %12

11:                                               ; preds = %1
  store ptr null, ptr %2, align 8
  br label %49

12:                                               ; preds = %1
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #2
  %13 = load ptr, ptr %3, align 8, !tbaa !5
  %14 = load ptr, ptr %13, align 8, !tbaa !5
  store ptr %14, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #2
  %15 = load ptr, ptr %3, align 8, !tbaa !5
  %16 = load ptr, ptr %15, align 8, !tbaa !5
  store ptr %16, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #2
  %17 = load ptr, ptr %3, align 8, !tbaa !5
  %18 = load ptr, ptr %17, align 8, !tbaa !5
  store ptr %18, ptr %6, align 8, !tbaa !5
  br label %19

19:                                               ; preds = %46, %12
  %20 = load ptr, ptr %4, align 8, !tbaa !5
  %21 = icmp ne ptr %20, null
  br i1 %21, label %22, label %25

22:                                               ; preds = %19
  %23 = load ptr, ptr %5, align 8, !tbaa !5
  %24 = icmp ne ptr %23, null
  br label %25

25:                                               ; preds = %22, %19
  %26 = phi i1 [ false, %19 ], [ %24, %22 ]
  br i1 %26, label %27, label %47

27:                                               ; preds = %25
  %28 = load ptr, ptr %5, align 8, !tbaa !5
  %29 = getelementptr inbounds %class.node, ptr %28, i32 0, i32 1
  %30 = load ptr, ptr %29, align 8, !tbaa !9
  store ptr %30, ptr %5, align 8, !tbaa !5
  %31 = load ptr, ptr %5, align 8, !tbaa !5
  %32 = icmp ne ptr %31, null
  br i1 %32, label %33, label %37

33:                                               ; preds = %27
  %34 = load ptr, ptr %5, align 8, !tbaa !5
  %35 = getelementptr inbounds %class.node, ptr %34, i32 0, i32 1
  %36 = load ptr, ptr %35, align 8, !tbaa !9
  store ptr %36, ptr %5, align 8, !tbaa !5
  br label %37

37:                                               ; preds = %33, %27
  %38 = load ptr, ptr %4, align 8, !tbaa !5
  %39 = getelementptr inbounds %class.node, ptr %38, i32 0, i32 1
  %40 = load ptr, ptr %39, align 8, !tbaa !9
  store ptr %40, ptr %4, align 8, !tbaa !5
  %41 = load ptr, ptr %4, align 8, !tbaa !5
  %42 = load ptr, ptr %5, align 8, !tbaa !5
  %43 = icmp eq ptr %41, %42
  br i1 %43, label %44, label %46

44:                                               ; preds = %37
  %45 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %45, ptr %2, align 8
  store i32 1, ptr %7, align 4
  br label %48

46:                                               ; preds = %37
  br label %19, !llvm.loop !12

47:                                               ; preds = %25
  store ptr null, ptr %2, align 8
  store i32 1, ptr %7, align 4
  br label %48

48:                                               ; preds = %47, %44
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #2
  br label %49

49:                                               ; preds = %48, %11
  %50 = load ptr, ptr %2, align 8
  ret ptr %50
}

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 = { 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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !6, i64 8}
!10 = !{!"_ZTS4node", !11, i64 0, !6, i64 8}
!11 = !{!"int", !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"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"

; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(read, inaccessiblemem: none) uwtable
define dso_local noundef ptr @_Z11floyd_cycleRP4node(ptr nocapture noundef nonnull readonly align 8 dereferenceable(8) %0) local_unnamed_addr #0 {
  %2 = load ptr, ptr %0, align 8, !tbaa !5
  %3 = icmp eq ptr %2, null
  br i1 %3, label %.loopexit, label %.preheader

.preheader:                                       ; preds = %1, %13
  %.016 = phi ptr [ %15, %13 ], [ %2, %1 ]
  %.014 = phi ptr [ %.115, %13 ], [ %2, %1 ]
  %4 = icmp ne ptr %.016, null
  %5 = icmp ne ptr %.014, null
  %6 = and i1 %4, %5
  br i1 %6, label %7, label %.loopexit

7:                                                ; preds = %.preheader
  %8 = getelementptr inbounds i8, ptr %.014, i64 8
  %9 = load ptr, ptr %8, align 8, !tbaa !9
  %.not = icmp eq ptr %9, null
  br i1 %.not, label %13, label %10

10:                                               ; preds = %7
  %11 = getelementptr inbounds i8, ptr %9, i64 8
  %12 = load ptr, ptr %11, align 8, !tbaa !9
  br label %13

13:                                               ; preds = %10, %7
  %.115 = phi ptr [ %12, %10 ], [ null, %7 ]
  %14 = getelementptr inbounds i8, ptr %.016, i64 8
  %15 = load ptr, ptr %14, align 8, !tbaa !9
  %16 = icmp eq ptr %15, %.115
  br i1 %16, label %.loopexit, label %.preheader, !llvm.loop !12

.loopexit:                                        ; preds = %13, %.preheader, %1
  %.1 = phi ptr [ null, %1 ], [ null, %.preheader ], [ %15, %13 ]
  ret ptr %.1
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(read, 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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !6, i64 8}
!10 = !{!"_ZTS4node", !11, i64 0, !6, i64 8}
!11 = !{!"int", !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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