; LLVM IR from Hunterdii/GeeksforGeeks-POTD :: March 2024 GFG SOLUTION (March-16)

; 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.Solution = type { i8 }
%struct.Node = type { i32, ptr }

@head = external dso_local global ptr, align 8
@.str = external hidden unnamed_addr constant [3 x i8], align 1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef ptr @_Z8findNodeP4Nodei(ptr noundef, i32 noundef) #0

; 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

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z6insertv() #2

declare i32 @__isoc99_scanf(ptr noundef, ...) #3

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z9printListP4Node(ptr noundef) #2

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #4 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca ptr, align 8
  %7 = alloca %class.Solution, align 1
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #5
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #5
  %8 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef %2)
  br label %9

9:                                                ; preds = %27, %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 %29

13:                                               ; preds = %9
  call void @_Z6insertv()
  %14 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef %3)
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #5
  %15 = load ptr, ptr @head, align 8, !tbaa !9
  %16 = load i32, ptr %3, align 4, !tbaa !5
  %17 = call noundef ptr @_Z8findNodeP4Nodei(ptr noundef %15, i32 noundef %16)
  store ptr %17, ptr %6, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 1, ptr %7) #5
  %18 = load ptr, ptr %6, align 8, !tbaa !9
  %19 = icmp ne ptr %18, null
  br i1 %19, label %20, label %27

20:                                               ; preds = %13
  %21 = load ptr, ptr %6, align 8, !tbaa !9
  %22 = getelementptr inbounds %struct.Node, ptr %21, i32 0, i32 1
  %23 = load ptr, ptr %22, align 8, !tbaa !11
  %24 = icmp ne ptr %23, null
  br i1 %24, label %25, label %27

25:                                               ; preds = %20
  %26 = load ptr, ptr %6, align 8, !tbaa !9
  call void @_ZN8Solution10deleteNodeEP4Node(ptr noundef nonnull align 1 dereferenceable(1) %7, ptr noundef %26)
  br label %27

27:                                               ; preds = %25, %20, %13
  %28 = load ptr, ptr @head, align 8, !tbaa !9
  call void @_Z9printListP4Node(ptr noundef %28)
  call void @llvm.lifetime.end.p0(i64 1, ptr %7) #5
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #5
  br label %9, !llvm.loop !13

29:                                               ; preds = %9
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #5
  ret i32 0
}

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZN8Solution10deleteNodeEP4Node(ptr noundef nonnull align 1 dereferenceable(1), ptr noundef) #0 align 2

attributes #0 = { 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 #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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 #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 = { 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 #5 = { 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.Solution = type { i8 }

@head = external dso_local local_unnamed_addr global ptr, align 8
@.str = external hidden unnamed_addr constant [3 x i8], align 1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef ptr @_Z8findNodeP4Nodei(ptr noundef, i32 noundef) local_unnamed_addr #0

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

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

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z6insertv() local_unnamed_addr #2

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #3

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z9printListP4Node(ptr noundef) local_unnamed_addr #2

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #4 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca %class.Solution, align 1
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #5
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #5
  %4 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull %1)
  %5 = load i32, ptr %1, align 4, !tbaa !5
  %6 = add nsw i32 %5, -1
  store i32 %6, ptr %1, align 4, !tbaa !5
  %.not5 = icmp eq i32 %5, 0
  br i1 %.not5, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %0, %15
  call void @_Z6insertv()
  %7 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull %2)
  %8 = load ptr, ptr @head, align 8, !tbaa !9
  %9 = load i32, ptr %2, align 4, !tbaa !5
  %10 = call noundef ptr @_Z8findNodeP4Nodei(ptr noundef %8, i32 noundef %9)
  call void @llvm.lifetime.start.p0(i64 1, ptr nonnull %3) #5
  %.not3 = icmp eq ptr %10, null
  br i1 %.not3, label %15, label %11

11:                                               ; preds = %.lr.ph
  %12 = getelementptr inbounds i8, ptr %10, i64 8
  %13 = load ptr, ptr %12, align 8, !tbaa !11
  %.not4 = icmp eq ptr %13, null
  br i1 %.not4, label %15, label %14

14:                                               ; preds = %11
  call void @_ZN8Solution10deleteNodeEP4Node(ptr noundef nonnull align 1 dereferenceable(1) %3, ptr noundef nonnull %10)
  br label %15

15:                                               ; preds = %14, %11, %.lr.ph
  %16 = load ptr, ptr @head, align 8, !tbaa !9
  call void @_Z9printListP4Node(ptr noundef %16)
  call void @llvm.lifetime.end.p0(i64 1, ptr nonnull %3) #5
  %17 = load i32, ptr %1, align 4, !tbaa !5
  %18 = add nsw i32 %17, -1
  store i32 %18, ptr %1, align 4, !tbaa !5
  %.not = icmp eq i32 %17, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !13

._crit_edge:                                      ; preds = %15, %0
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #5
  ret i32 0
}

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZN8Solution10deleteNodeEP4Node(ptr noundef nonnull align 1 dereferenceable(1), ptr noundef) local_unnamed_addr #0 align 2

attributes #0 = { 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 #1 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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 #3 = { nofree 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 #4 = { 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 #5 = { 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"}


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