; LLVM IR from AlgoGenesis/C :: Linked_list/Circular_Linked_List/Circular_Doubly_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"

%struct.Node = type { i32, ptr, ptr }

@.str = external hidden unnamed_addr constant [16 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [2 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: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

declare i32 @printf(ptr noundef, ...) #1

; Function Attrs: nounwind uwtable
define dso_local void @traverseBackward(ptr noundef %0) #2 {
  %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)
  br label %28

9:                                                ; preds = %1
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #3
  %10 = load ptr, ptr %2, align 8, !tbaa !5
  %11 = getelementptr inbounds %struct.Node, ptr %10, i32 0, i32 2
  %12 = load ptr, ptr %11, align 8, !tbaa !9
  store ptr %12, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #3
  %13 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %13, ptr %4, align 8, !tbaa !5
  br label %14

14:                                               ; preds = %22, %9
  %15 = load ptr, ptr %4, align 8, !tbaa !5
  %16 = getelementptr inbounds %struct.Node, ptr %15, i32 0, i32 0
  %17 = load i32, ptr %16, align 8, !tbaa !12
  %18 = call i32 (ptr, ...) @printf(ptr noundef @.str.2, i32 noundef %17)
  %19 = load ptr, ptr %4, align 8, !tbaa !5
  %20 = getelementptr inbounds %struct.Node, ptr %19, i32 0, i32 2
  %21 = load ptr, ptr %20, align 8, !tbaa !9
  store ptr %21, ptr %4, align 8, !tbaa !5
  br label %22

22:                                               ; preds = %14
  %23 = load ptr, ptr %4, align 8, !tbaa !5
  %24 = load ptr, ptr %3, align 8, !tbaa !5
  %25 = icmp ne ptr %23, %24
  br i1 %25, label %14, label %26, !llvm.loop !13

26:                                               ; preds = %22
  %27 = call i32 (ptr, ...) @printf(ptr noundef @.str.3)
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #3
  br label %28

28:                                               ; preds = %26, %7
  ret void
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { "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 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 }

!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 16}
!10 = !{!"Node", !11, i64 0, !6, i64 8, !6, i64 16}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !11, i64 0}
!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"

@.str = external hidden unnamed_addr constant [16 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [2 x i8], align 1

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #0

; Function Attrs: nofree nounwind uwtable
define dso_local void @traverseBackward(ptr noundef readonly %0) local_unnamed_addr #1 {
  %2 = icmp eq ptr %0, null
  br i1 %2, label %.loopexit, label %3

3:                                                ; preds = %1
  %4 = getelementptr inbounds i8, ptr %0, i64 16
  %5 = load ptr, ptr %4, align 8, !tbaa !5
  br label %6

6:                                                ; preds = %6, %3
  %.0 = phi ptr [ %5, %3 ], [ %10, %6 ]
  %7 = load i32, ptr %.0, align 8, !tbaa !11
  %8 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.2, i32 noundef %7)
  %9 = getelementptr inbounds i8, ptr %.0, i64 16
  %10 = load ptr, ptr %9, align 8, !tbaa !5
  %.not = icmp eq ptr %10, %5
  br i1 %.not, label %.loopexit, label %6, !llvm.loop !12

.loopexit:                                        ; preds = %6, %1
  %.str.3.sink = phi ptr [ @.str, %1 ], [ @.str.3, %6 ]
  %11 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) %.str.3.sink)
  ret void
}

attributes #0 = { 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 #1 = { 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" }

!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 16}
!6 = !{!"Node", !7, i64 0, !10, i64 8, !10, i64 16}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = !{!6, !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass