; LLVM IR from Leet-Us-Code/DSA-A-Z-Practice :: Companies/Cognizant GenC next (Linked List Implementation)

; 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::basic_istream" = type { ptr, i64, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }

@_ZSt3cin = external global %"class.std::basic_istream", align 8

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z9printListP4Node(ptr noundef) #0

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #1 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #4
  %8 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %2)
  br label %9

9:                                                ; preds = %37, %0
  %10 = load i32, ptr %2, align 4, !tbaa !5
  %11 = add nsw i32 %10, -1
  store i32 %11, ptr %2, align 4, !tbaa !5
  %12 = icmp ne i32 %10, 0
  br i1 %12, label %13, label %39

13:                                               ; preds = %9
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #4
  %14 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %3)
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  store ptr null, ptr %4, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #4
  store i32 0, ptr %5, align 4, !tbaa !5
  br label %15

15:                                               ; preds = %34, %13
  %16 = load i32, ptr %5, align 4, !tbaa !5
  %17 = load i32, ptr %3, align 4, !tbaa !5
  %18 = icmp slt i32 %16, %17
  br i1 %18, label %20, label %19

19:                                               ; preds = %15
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #4
  br label %37

20:                                               ; preds = %15
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #4
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #4
  %21 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %6)
  %22 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %7)
  %23 = load i32, ptr %7, align 4, !tbaa !5
  %24 = icmp ne i32 %23, 0
  br i1 %24, label %25, label %29

25:                                               ; preds = %20
  %26 = load ptr, ptr %4, align 8, !tbaa !9
  %27 = load i32, ptr %6, align 4, !tbaa !5
  %28 = call noundef ptr @_Z11insertAtEndP4Nodei(ptr noundef %26, i32 noundef %27)
  store ptr %28, ptr %4, align 8, !tbaa !9
  br label %33

29:                                               ; preds = %20
  %30 = load ptr, ptr %4, align 8, !tbaa !9
  %31 = load i32, ptr %6, align 4, !tbaa !5
  %32 = call noundef ptr @_Z16insertAtBeginingP4Nodei(ptr noundef %30, i32 noundef %31)
  store ptr %32, ptr %4, align 8, !tbaa !9
  br label %33

33:                                               ; preds = %29, %25
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #4
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #4
  br label %34

34:                                               ; preds = %33
  %35 = load i32, ptr %5, align 4, !tbaa !5
  %36 = add nsw i32 %35, 1
  store i32 %36, ptr %5, align 4, !tbaa !5
  br label %15, !llvm.loop !11

37:                                               ; preds = %19
  %38 = load ptr, ptr %4, align 8, !tbaa !9
  call void @_Z9printListP4Node(ptr noundef %38)
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #4
  br label %9, !llvm.loop !13

39:                                               ; preds = %9
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #4
  ret i32 0
}

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) #3

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_Z11insertAtEndP4Nodei(ptr noundef, i32 noundef) #0

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_Z16insertAtBeginingP4Nodei(ptr noundef, i32 noundef) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #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 norecurse 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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #3 = { "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 = { 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 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = distinct !{!13, !12}


; 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::basic_istream" = type { ptr, i64, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }

@_ZSt3cin = external global %"class.std::basic_istream", align 8

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z9printListP4Node(ptr noundef) local_unnamed_addr #0

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #1 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #4
  %5 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %1)
  %6 = load i32, ptr %1, align 4, !tbaa !5
  %7 = add nsw i32 %6, -1
  store i32 %7, ptr %1, align 4, !tbaa !5
  %.not8 = icmp eq i32 %6, 0
  br i1 %.not8, label %._crit_edge11, label %.lr.ph10

.lr.ph10:                                         ; preds = %0, %._crit_edge
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #4
  %8 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %2)
  %9 = load i32, ptr %2, align 4, !tbaa !5
  %10 = icmp sgt i32 %9, 0
  br i1 %10, label %.lr.ph, label %._crit_edge

._crit_edge:                                      ; preds = %21, %.lr.ph10
  %.04.lcssa = phi ptr [ null, %.lr.ph10 ], [ %.1, %21 ]
  call void @_Z9printListP4Node(ptr noundef %.04.lcssa)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #4
  %11 = load i32, ptr %1, align 4, !tbaa !5
  %12 = add nsw i32 %11, -1
  store i32 %12, ptr %1, align 4, !tbaa !5
  %.not = icmp eq i32 %11, 0
  br i1 %.not, label %._crit_edge11, label %.lr.ph10, !llvm.loop !9

.lr.ph:                                           ; preds = %.lr.ph10, %21
  %.07 = phi i32 [ %22, %21 ], [ 0, %.lr.ph10 ]
  %.046 = phi ptr [ %.1, %21 ], [ null, %.lr.ph10 ]
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %3) #4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %4) #4
  %13 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %3)
  %14 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %4)
  %15 = load i32, ptr %4, align 4, !tbaa !5
  %.not5 = icmp eq i32 %15, 0
  %16 = load i32, ptr %3, align 4, !tbaa !5
  br i1 %.not5, label %19, label %17

17:                                               ; preds = %.lr.ph
  %18 = call noundef ptr @_Z11insertAtEndP4Nodei(ptr noundef %.046, i32 noundef %16)
  br label %21

19:                                               ; preds = %.lr.ph
  %20 = call noundef ptr @_Z16insertAtBeginingP4Nodei(ptr noundef %.046, i32 noundef %16)
  br label %21

21:                                               ; preds = %19, %17
  %.1 = phi ptr [ %18, %17 ], [ %20, %19 ]
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %4) #4
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %3) #4
  %22 = add nuw nsw i32 %.07, 1
  %23 = load i32, ptr %2, align 4, !tbaa !5
  %24 = icmp slt i32 %22, %23
  br i1 %24, label %.lr.ph, label %._crit_edge, !llvm.loop !11

._crit_edge11:                                    ; preds = %._crit_edge, %0
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #4
  ret i32 0
}

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #3

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_Z11insertAtEndP4Nodei(ptr noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_Z16insertAtBeginingP4Nodei(ptr noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #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 norecurse 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 nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #3 = { "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 = { 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 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}


; Effective O3 passes: GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass