; LLVM IR from HarshCasper/NeoAlgo :: C/ds (Circular_LL)

; 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"

%struct.node = type { i32, ptr }

@.str.4 = external hidden unnamed_addr constant [13 x i8], align 1
@.str.5 = external hidden unnamed_addr constant [10 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [20 x i8], align 1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nounwind allocsize(0)
declare noalias ptr @malloc(i64 noundef) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

declare i32 @printf(ptr noundef, ...) #2

; Function Attrs: nounwind uwtable
define dso_local ptr @delete_at_end(ptr noundef %0) #3 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  store ptr %0, ptr %2, align 8, !tbaa !5
  %5 = load ptr, ptr %2, align 8, !tbaa !5
  %6 = icmp eq ptr %5, null
  br i1 %6, label %7, label %9

7:                                                ; preds = %1
  %8 = call i32 (ptr, ...) @printf(ptr noundef @.str.4)
  br label %39

9:                                                ; preds = %1
  %10 = load ptr, ptr %2, align 8, !tbaa !5
  %11 = getelementptr inbounds %struct.node, ptr %10, i32 0, i32 1
  %12 = load ptr, ptr %11, align 8, !tbaa !9
  %13 = load ptr, ptr %2, align 8, !tbaa !5
  %14 = icmp eq ptr %12, %13
  br i1 %14, label %15, label %17

15:                                               ; preds = %9
  store ptr null, ptr %2, align 8, !tbaa !5
  %16 = call i32 (ptr, ...) @printf(ptr noundef @.str.5)
  br label %38

17:                                               ; preds = %9
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #4
  %18 = load ptr, ptr %2, align 8, !tbaa !5
  store ptr %18, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  %19 = call noalias ptr @malloc(i64 noundef 16) #5
  store ptr %19, ptr %4, align 8, !tbaa !5
  br label %20

20:                                               ; preds = %26, %17
  %21 = load ptr, ptr %3, align 8, !tbaa !5
  %22 = getelementptr inbounds %struct.node, ptr %21, i32 0, i32 1
  %23 = load ptr, ptr %22, align 8, !tbaa !9
  %24 = load ptr, ptr %2, align 8, !tbaa !5
  %25 = icmp ne ptr %23, %24
  br i1 %25, label %26, label %31

26:                                               ; preds = %20
  %27 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %27, ptr %4, align 8, !tbaa !5
  %28 = load ptr, ptr %3, align 8, !tbaa !5
  %29 = getelementptr inbounds %struct.node, ptr %28, i32 0, i32 1
  %30 = load ptr, ptr %29, align 8, !tbaa !9
  store ptr %30, ptr %3, align 8, !tbaa !5
  br label %20, !llvm.loop !12

31:                                               ; preds = %20
  %32 = load ptr, ptr %3, align 8, !tbaa !5
  %33 = getelementptr inbounds %struct.node, ptr %32, i32 0, i32 1
  %34 = load ptr, ptr %33, align 8, !tbaa !9
  %35 = load ptr, ptr %4, align 8, !tbaa !5
  %36 = getelementptr inbounds %struct.node, ptr %35, i32 0, i32 1
  store ptr %34, ptr %36, align 8, !tbaa !9
  %37 = call i32 (ptr, ...) @printf(ptr noundef @.str.6)
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #4
  br label %38

38:                                               ; preds = %31, %15
  br label %39

39:                                               ; preds = %38, %7
  %40 = load ptr, ptr %2, align 8, !tbaa !5
  ret ptr %40
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { nounwind 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 #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 = { 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 #4 = { nounwind }
attributes #5 = { nounwind 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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !6, i64 8}
!10 = !{!"node", !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"

@.str.4 = external hidden unnamed_addr constant [13 x i8], align 1
@.str.5 = external hidden unnamed_addr constant [10 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [20 x i8], align 1

; Function Attrs: mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite)
declare noalias noundef ptr @malloc(i64 noundef) local_unnamed_addr #0

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #1

; Function Attrs: nofree nounwind uwtable
define dso_local noundef ptr @delete_at_end(ptr noundef %0) local_unnamed_addr #2 {
  %2 = icmp eq ptr %0, null
  br i1 %2, label %14, label %3

3:                                                ; preds = %1
  %4 = getelementptr inbounds i8, ptr %0, i64 8
  %5 = load ptr, ptr %4, align 8, !tbaa !5
  %6 = icmp eq ptr %5, %0
  br i1 %6, label %14, label %7

7:                                                ; preds = %3
  %8 = tail call noalias dereferenceable_or_null(16) ptr @malloc(i64 noundef 16) #3
  br label %9

9:                                                ; preds = %9, %7
  %.011 = phi ptr [ %0, %7 ], [ %11, %9 ]
  %.0 = phi ptr [ %8, %7 ], [ %.011, %9 ]
  %10 = getelementptr inbounds i8, ptr %.011, i64 8
  %11 = load ptr, ptr %10, align 8, !tbaa !5
  %.not = icmp eq ptr %11, %0
  br i1 %.not, label %12, label %9, !llvm.loop !11

12:                                               ; preds = %9
  %13 = getelementptr inbounds i8, ptr %.0, i64 8
  store ptr %11, ptr %13, align 8, !tbaa !5
  br label %14

14:                                               ; preds = %3, %1, %12
  %.str.5.sink = phi ptr [ @.str.6, %12 ], [ @.str.4, %1 ], [ @.str.5, %3 ]
  %.012 = phi ptr [ %0, %12 ], [ null, %1 ], [ null, %3 ]
  %15 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) %.str.5.sink)
  ret ptr %.012
}

attributes #0 = { mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite) "alloc-family"="malloc" "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 = { 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 #2 = { nofree 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 = { nounwind 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, !10, i64 8}
!6 = !{!"node", !7, i64 0, !10, i64 8}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass