; 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 }

; Function Attrs: nounwind uwtable
define dso_local ptr @insert_at_beg(ptr noundef %0, i32 noundef %1) #0 {
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  %5 = alloca ptr, align 8
  %6 = alloca ptr, align 8
  store ptr %0, ptr %3, align 8, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #3
  %7 = call noalias ptr @malloc(i64 noundef 16) #4
  store ptr %7, ptr %5, align 8, !tbaa !5
  %8 = load i32, ptr %4, align 4, !tbaa !9
  %9 = load ptr, ptr %5, align 8, !tbaa !5
  %10 = getelementptr inbounds %struct.node, ptr %9, i32 0, i32 0
  store i32 %8, ptr %10, align 8, !tbaa !11
  %11 = load ptr, ptr %3, align 8, !tbaa !5
  %12 = icmp eq ptr %11, null
  br i1 %12, label %13, label %18

13:                                               ; preds = %2
  %14 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %14, ptr %3, align 8, !tbaa !5
  %15 = load ptr, ptr %3, align 8, !tbaa !5
  %16 = load ptr, ptr %5, align 8, !tbaa !5
  %17 = getelementptr inbounds %struct.node, ptr %16, i32 0, i32 1
  store ptr %15, ptr %17, align 8, !tbaa !13
  br label %38

18:                                               ; preds = %2
  %19 = load ptr, ptr %3, align 8, !tbaa !5
  %20 = load ptr, ptr %5, align 8, !tbaa !5
  %21 = getelementptr inbounds %struct.node, ptr %20, i32 0, i32 1
  store ptr %19, ptr %21, align 8, !tbaa !13
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #3
  %22 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %22, ptr %6, align 8, !tbaa !5
  br label %23

23:                                               ; preds = %29, %18
  %24 = load ptr, ptr %6, align 8, !tbaa !5
  %25 = getelementptr inbounds %struct.node, ptr %24, i32 0, i32 1
  %26 = load ptr, ptr %25, align 8, !tbaa !13
  %27 = load ptr, ptr %3, align 8, !tbaa !5
  %28 = icmp ne ptr %26, %27
  br i1 %28, label %29, label %33

29:                                               ; preds = %23
  %30 = load ptr, ptr %6, align 8, !tbaa !5
  %31 = getelementptr inbounds %struct.node, ptr %30, i32 0, i32 1
  %32 = load ptr, ptr %31, align 8, !tbaa !13
  store ptr %32, ptr %6, align 8, !tbaa !5
  br label %23, !llvm.loop !14

33:                                               ; preds = %23
  %34 = load ptr, ptr %5, align 8, !tbaa !5
  %35 = load ptr, ptr %6, align 8, !tbaa !5
  %36 = getelementptr inbounds %struct.node, ptr %35, i32 0, i32 1
  store ptr %34, ptr %36, align 8, !tbaa !13
  %37 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %37, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #3
  br label %38

38:                                               ; preds = %33, %13
  %39 = load ptr, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #3
  ret ptr %39
}

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

; Function Attrs: nounwind allocsize(0)
declare noalias ptr @malloc(i64 noundef) #2

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

attributes #0 = { 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 = { 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 #3 = { nounwind }
attributes #4 = { 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, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{!12, !10, i64 0}
!12 = !{!"node", !10, i64 0, !6, i64 8}
!13 = !{!12, !6, i64 8}
!14 = distinct !{!14, !15}
!15 = !{!"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"

; Function Attrs: nofree nounwind uwtable
define dso_local noundef ptr @insert_at_beg(ptr noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = tail call noalias dereferenceable_or_null(16) ptr @malloc(i64 noundef 16) #2
  store i32 %1, ptr %3, align 8, !tbaa !5
  %4 = icmp eq ptr %0, null
  %5 = getelementptr inbounds i8, ptr %3, i64 8
  br i1 %4, label %12, label %6

6:                                                ; preds = %2
  store ptr %0, ptr %5, align 8, !tbaa !11
  br label %7

7:                                                ; preds = %7, %6
  %.0 = phi ptr [ %0, %6 ], [ %9, %7 ]
  %8 = getelementptr inbounds i8, ptr %.0, i64 8
  %9 = load ptr, ptr %8, align 8, !tbaa !11
  %.not = icmp eq ptr %9, %0
  br i1 %.not, label %10, label %7, !llvm.loop !12

10:                                               ; preds = %7
  %11 = getelementptr inbounds i8, ptr %.0, i64 8
  br label %12

12:                                               ; preds = %2, %10
  %.sink = phi ptr [ %11, %10 ], [ %5, %2 ]
  store ptr %3, ptr %.sink, align 8, !tbaa !11
  ret ptr %3
}

; Function Attrs: mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite)
declare noalias noundef ptr @malloc(i64 noundef) local_unnamed_addr #1

attributes #0 = { 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 #1 = { 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 #2 = { 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, !7, i64 0}
!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 = !{!6, !10, i64 8}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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