; LLVM IR from Lakhankumawat/LearnCPP :: L-LinkedList/Merge K Sorted LinkedList/merge_k_ll.ll (Z9takeInputi)

; 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 }
%class.Node = type { i32, ptr }

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

; Function Attrs: mustprogress uwtable
define dso_local noundef ptr @_Z9takeInputi(i32 noundef %0) #0 personality ptr @__gxx_personality_v0 {
  %2 = alloca i32, align 4
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca ptr, align 8
  %8 = alloca ptr, align 8
  %9 = alloca i32, align 4
  store i32 %0, ptr %2, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #6
  store ptr null, ptr %3, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #6
  store ptr null, ptr %4, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #6
  store i32 0, ptr %5, align 4, !tbaa !5
  br label %10

10:                                               ; preds = %37, %1
  %11 = load i32, ptr %5, align 4, !tbaa !5
  %12 = load i32, ptr %2, align 4, !tbaa !5
  %13 = icmp slt i32 %11, %12
  br i1 %13, label %15, label %14

14:                                               ; preds = %10
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #6
  br label %40

15:                                               ; preds = %10
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #6
  %16 = 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)
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #6
  %17 = call noalias noundef nonnull ptr @_Znwm(i64 noundef 16) #7
  %18 = load i32, ptr %6, align 4, !tbaa !5
  invoke void @_ZN4NodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16) %17, i32 noundef %18)
          to label %19 unwind label %25

19:                                               ; preds = %15
  store ptr %17, ptr %7, align 8, !tbaa !9
  %20 = load ptr, ptr %3, align 8, !tbaa !9
  %21 = icmp eq ptr %20, null
  br i1 %21, label %22, label %29

22:                                               ; preds = %19
  %23 = load ptr, ptr %7, align 8, !tbaa !9
  store ptr %23, ptr %3, align 8, !tbaa !9
  %24 = load ptr, ptr %7, align 8, !tbaa !9
  store ptr %24, ptr %4, align 8, !tbaa !9
  br label %36

25:                                               ; preds = %15
  %26 = landingpad { ptr, i32 }
          cleanup
  %27 = extractvalue { ptr, i32 } %26, 0
  store ptr %27, ptr %8, align 8
  %28 = extractvalue { ptr, i32 } %26, 1
  store i32 %28, ptr %9, align 4
  call void @_ZdlPvm(ptr noundef %17, i64 noundef 16) #8
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #6
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #6
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #6
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #6
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #6
  br label %42

29:                                               ; preds = %19
  %30 = load ptr, ptr %7, align 8, !tbaa !9
  %31 = load ptr, ptr %4, align 8, !tbaa !9
  %32 = getelementptr inbounds %class.Node, ptr %31, i32 0, i32 1
  store ptr %30, ptr %32, align 8, !tbaa !11
  %33 = load ptr, ptr %4, align 8, !tbaa !9
  %34 = getelementptr inbounds %class.Node, ptr %33, i32 0, i32 1
  %35 = load ptr, ptr %34, align 8, !tbaa !11
  store ptr %35, ptr %4, align 8, !tbaa !9
  br label %36

36:                                               ; preds = %29, %22
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #6
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #6
  br label %37

37:                                               ; preds = %36
  %38 = load i32, ptr %5, align 4, !tbaa !5
  %39 = add nsw i32 %38, 1
  store i32 %39, ptr %5, align 4, !tbaa !5
  br label %10, !llvm.loop !13

40:                                               ; preds = %14
  %41 = load ptr, ptr %3, align 8, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #6
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #6
  ret ptr %41

42:                                               ; preds = %25
  %43 = load ptr, ptr %8, align 8
  %44 = load i32, ptr %9, align 4
  %45 = insertvalue { ptr, i32 } poison, ptr %43, 0
  %46 = insertvalue { ptr, i32 } %45, i32 %44, 1
  resume { ptr, i32 } %46
}

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

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) #2

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

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZN4NodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16), i32 noundef) unnamed_addr #4 align 2

declare i32 @__gxx_personality_v0(...)

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

; 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 = { "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 = !{!"_ZTS4Node", !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.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
define dso_local noundef ptr @_Z9takeInputi(i32 noundef %0) local_unnamed_addr #0 personality ptr @__gxx_personality_v0 {
  %2 = alloca i32, align 4
  %3 = icmp sgt i32 %0, 0
  br i1 %3, label %.lr.ph, label %._crit_edge

._crit_edge:                                      ; preds = %10, %1
  %.0.lcssa = phi ptr [ null, %1 ], [ %.1, %10 ]
  ret ptr %.0.lcssa

.lr.ph:                                           ; preds = %1, %10
  %.014 = phi ptr [ %.1, %10 ], [ null, %1 ]
  %.0913 = phi i32 [ %11, %10 ], [ 0, %1 ]
  %.01012 = phi ptr [ %5, %10 ], [ null, %1 ]
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #5
  %4 = 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)
  %5 = call noalias noundef nonnull dereferenceable(16) ptr @_Znwm(i64 noundef 16) #6
  %6 = load i32, ptr %2, align 4, !tbaa !5
  call void @_ZN4NodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16) %5, i32 noundef %6)
  %7 = icmp eq ptr %.014, null
  br i1 %7, label %10, label %8

8:                                                ; preds = %.lr.ph
  %9 = getelementptr inbounds i8, ptr %.01012, i64 8
  store ptr %5, ptr %9, align 8, !tbaa !9
  br label %10

10:                                               ; preds = %.lr.ph, %8
  %.1 = phi ptr [ %.014, %8 ], [ %5, %.lr.ph ]
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #5
  %11 = add nuw nsw i32 %.0913, 1
  %exitcond.not = icmp eq i32 %11, %0
  br i1 %exitcond.not, label %._crit_edge, label %.lr.ph, !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

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 #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 void @_ZN4NodeC2Ei(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

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 = { "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 = !{!"_ZTS4Node", !6, i64 0, !11, i64 8}
!11 = !{!"any pointer", !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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