; LLVM IR from pezy/LeetCode :: 018. Remove Nth Node from End of List (main)

; 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.__gnu_cxx::__normal_iterator" = type { ptr }
%struct.ListNode = type { i32, ptr }

; Function Attrs: mustprogress uwtable
define dso_local noundef ptr @_Z16createLinkedListN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEES5_(ptr %0, ptr %1) #0 personality ptr @__gxx_personality_v0 {
  %3 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %4 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %5 = alloca ptr, align 8
  %6 = alloca ptr, align 8
  %7 = alloca i1, align 1
  %8 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %9 = alloca ptr, align 8
  %10 = alloca i32, align 4
  %11 = alloca ptr, align 8
  %12 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %13 = alloca i1, align 1
  %14 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %3, i32 0, i32 0
  store ptr %0, ptr %14, align 8
  %15 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %4, i32 0, i32 0
  store ptr %1, ptr %15, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #6
  %16 = call noundef zeroext i1 @_ZN9__gnu_cxxeqIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8) %3, ptr noundef nonnull align 8 dereferenceable(8) %4) #6
  store i1 false, ptr %7, align 1
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #6
  br i1 %16, label %17, label %18

17:                                               ; preds = %2
  br label %25

18:                                               ; preds = %2
  %19 = call noalias noundef nonnull ptr @_Znwm(i64 noundef 16) #7
  store ptr %19, ptr %6, align 8
  store i1 true, ptr %7, align 1
  %20 = call ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEi(ptr noundef nonnull align 8 dereferenceable(8) %3, i32 noundef 0) #6
  %21 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %8, i32 0, i32 0
  store ptr %20, ptr %21, align 8
  %22 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %8) #6
  %23 = load i32, ptr %22, align 4, !tbaa !5
  invoke void @_ZN8ListNodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16) %19, i32 noundef %23)
          to label %24 unwind label %31

24:                                               ; preds = %18
  store i1 false, ptr %7, align 1
  br label %25

25:                                               ; preds = %24, %17
  %26 = phi ptr [ null, %17 ], [ %19, %24 ]
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #6
  store ptr %26, ptr %5, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %11) #6
  %27 = load ptr, ptr %5, align 8, !tbaa !9
  store ptr %27, ptr %11, align 8, !tbaa !9
  br label %28

28:                                               ; preds = %48, %25
  %29 = call noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8) %3, ptr noundef nonnull align 8 dereferenceable(8) %4) #6
  br i1 %29, label %39, label %30

30:                                               ; preds = %28
  call void @llvm.lifetime.end.p0(i64 8, ptr %11) #6
  br label %59

31:                                               ; preds = %18
  %32 = landingpad { ptr, i32 }
          cleanup
  %33 = extractvalue { ptr, i32 } %32, 0
  store ptr %33, ptr %9, align 8
  %34 = extractvalue { ptr, i32 } %32, 1
  store i32 %34, ptr %10, align 4
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #6
  %35 = load i1, ptr %7, align 1
  br i1 %35, label %36, label %38

36:                                               ; preds = %31
  %37 = load ptr, ptr %6, align 8
  call void @_ZdlPvm(ptr noundef %37, i64 noundef 16) #8
  br label %38

38:                                               ; preds = %36, %31
  br label %61

39:                                               ; preds = %28
  %40 = call noalias noundef nonnull ptr @_Znwm(i64 noundef 16) #7
  store i1 true, ptr %13, align 1
  call void @llvm.lifetime.start.p0(i64 8, ptr %12) #6
  %41 = call ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEi(ptr noundef nonnull align 8 dereferenceable(8) %3, i32 noundef 0) #6
  %42 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %12, i32 0, i32 0
  store ptr %41, ptr %42, align 8
  %43 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %12) #6
  %44 = load i32, ptr %43, align 4, !tbaa !5
  invoke void @_ZN8ListNodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16) %40, i32 noundef %44)
          to label %45 unwind label %52

45:                                               ; preds = %39
  store i1 false, ptr %13, align 1
  %46 = load ptr, ptr %11, align 8, !tbaa !9
  %47 = getelementptr inbounds %struct.ListNode, ptr %46, i32 0, i32 1
  store ptr %40, ptr %47, align 8, !tbaa !11
  call void @llvm.lifetime.end.p0(i64 8, ptr %12) #6
  br label %48

48:                                               ; preds = %45
  %49 = load ptr, ptr %11, align 8, !tbaa !9
  %50 = getelementptr inbounds %struct.ListNode, ptr %49, i32 0, i32 1
  %51 = load ptr, ptr %50, align 8, !tbaa !11
  store ptr %51, ptr %11, align 8, !tbaa !9
  br label %28, !llvm.loop !13

52:                                               ; preds = %39
  %53 = landingpad { ptr, i32 }
          cleanup
  %54 = extractvalue { ptr, i32 } %53, 0
  store ptr %54, ptr %9, align 8
  %55 = extractvalue { ptr, i32 } %53, 1
  store i32 %55, ptr %10, align 4
  call void @llvm.lifetime.end.p0(i64 8, ptr %12) #6
  %56 = load i1, ptr %13, align 1
  br i1 %56, label %57, label %58

57:                                               ; preds = %52
  call void @_ZdlPvm(ptr noundef %40, i64 noundef 16) #8
  br label %58

58:                                               ; preds = %57, %52
  call void @llvm.lifetime.end.p0(i64 8, ptr %11) #6
  br label %61

59:                                               ; preds = %30
  %60 = load ptr, ptr %5, align 8, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #6
  ret ptr %60

61:                                               ; preds = %58, %38
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #6
  br label %62

62:                                               ; preds = %61
  %63 = load ptr, ptr %9, align 8
  %64 = load i32, ptr %10, align 4
  %65 = insertvalue { ptr, i32 } poison, ptr %63, 0
  %66 = insertvalue { ptr, i32 } %65, i32 %64, 1
  resume { ptr, i32 } %66
}

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZN9__gnu_cxxeqIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef nonnull align 8 dereferenceable(8)) #2

; Function Attrs: nobuiltin allocsize(0)
declare noundef nonnull ptr @_Znwm(i64 noundef) #3

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) #4 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8)) #4 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZN8ListNodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16), i32 noundef) unnamed_addr #4 align 2

declare i32 @__gxx_personality_v0(...)

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: nobuiltin nounwind
declare void @_ZdlPvm(ptr noundef, i64 noundef) #5

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef nonnull align 8 dereferenceable(8)) #2

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 = { inlinehint 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 = { nobuiltin allocsize(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 #4 = { 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 #5 = { nobuiltin nounwind "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 #6 = { nounwind }
attributes #7 = { builtin allocsize(0) }
attributes #8 = { builtin 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 = !{!12, !10, i64 8}
!12 = !{!"_ZTS8ListNode", !6, i64 0, !10, i64 8}
!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.__gnu_cxx::__normal_iterator" = type { ptr }

; Function Attrs: mustprogress uwtable
define dso_local noundef ptr @_Z16createLinkedListN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEES5_(ptr %0, ptr %1) local_unnamed_addr #0 personality ptr @__gxx_personality_v0 {
  %3 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %4 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %5 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %6 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  store ptr %0, ptr %3, align 8
  store ptr %1, ptr %4, align 8
  %7 = call noundef zeroext i1 @_ZN9__gnu_cxxeqIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8) %3, ptr noundef nonnull align 8 dereferenceable(8) %4) #5
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %5) #5
  br i1 %7, label %13, label %8

8:                                                ; preds = %2
  %9 = call noalias noundef nonnull dereferenceable(16) ptr @_Znwm(i64 noundef 16) #6
  %10 = call ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEi(ptr noundef nonnull align 8 dereferenceable(8) %3, i32 noundef 0) #5
  store ptr %10, ptr %5, align 8
  %11 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %5) #5
  %12 = load i32, ptr %11, align 4, !tbaa !5
  call void @_ZN8ListNodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16) %9, i32 noundef %12)
  br label %13

13:                                               ; preds = %2, %8
  %14 = phi ptr [ %9, %8 ], [ null, %2 ]
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %5) #5
  %15 = call noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8) %3, ptr noundef nonnull align 8 dereferenceable(8) %4) #5
  br i1 %15, label %.lr.ph, label %._crit_edge

._crit_edge:                                      ; preds = %.lr.ph, %13
  ret ptr %14

.lr.ph:                                           ; preds = %13, %.lr.ph
  %.04 = phi ptr [ %16, %.lr.ph ], [ %14, %13 ]
  %16 = call noalias noundef nonnull dereferenceable(16) ptr @_Znwm(i64 noundef 16) #6
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %6) #5
  %17 = call ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEi(ptr noundef nonnull align 8 dereferenceable(8) %3, i32 noundef 0) #5
  store ptr %17, ptr %6, align 8
  %18 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %6) #5
  %19 = load i32, ptr %18, align 4, !tbaa !5
  call void @_ZN8ListNodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16) %16, i32 noundef %19)
  %20 = getelementptr inbounds i8, ptr %.04, i64 8
  store ptr %16, ptr %20, align 8, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %6) #5
  %21 = call noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8) %3, ptr noundef nonnull align 8 dereferenceable(8) %4) #5
  br i1 %21, label %.lr.ph, label %._crit_edge, !llvm.loop !12
}

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZN9__gnu_cxxeqIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #2

; Function Attrs: nobuiltin allocsize(0)
declare noundef nonnull ptr @_Znwm(i64 noundef) local_unnamed_addr #3

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEppEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) local_unnamed_addr #4 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #4 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZN8ListNodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16), i32 noundef) unnamed_addr #4 align 2

declare i32 @__gxx_personality_v0(...)

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZN9__gnu_cxxneIPiSt6vectorIiSaIiEEEEbRKNS_17__normal_iteratorIT_T0_EESA_(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #2

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 = { inlinehint 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 = { nobuiltin allocsize(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 #4 = { 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 #5 = { nounwind }
attributes #6 = { builtin allocsize(0) }

!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, !11, i64 8}
!10 = !{!"_ZTS8ListNode", !6, i64 0, !11, i64 8}
!11 = !{!"any pointer", !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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