; LLVM IR from HarshCasper/NeoAlgo :: C-Plus-Plus/other/odd_even_linked_list.ll (Z20odd_even_linked_listP8ListNode)

; 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.ListNode = type { i32, ptr }

; Function Attrs: mustprogress uwtable
define dso_local noundef ptr @_Z20odd_even_linked_listP8ListNode(ptr noundef %0) #0 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca ptr, align 8
  %7 = alloca ptr, align 8
  store ptr %0, ptr %3, align 8, !tbaa !5
  %8 = load ptr, ptr %3, align 8, !tbaa !5
  %9 = getelementptr inbounds %class.ListNode, ptr %8, i32 0, i32 1
  %10 = load ptr, ptr %9, align 8, !tbaa !9
  %11 = icmp eq ptr %10, null
  br i1 %11, label %12, label %14

12:                                               ; preds = %1
  %13 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %13, ptr %2, align 8
  br label %61

14:                                               ; preds = %1
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  %15 = call noalias noundef nonnull ptr @_Znwm(i64 noundef 16) #5
  call void @llvm.memset.p0.i64(ptr align 16 %15, i8 0, i64 16, i1 false)
  store ptr %15, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #4
  %16 = call noalias noundef nonnull ptr @_Znwm(i64 noundef 16) #5
  call void @llvm.memset.p0.i64(ptr align 16 %16, i8 0, i64 16, i1 false)
  store ptr %16, ptr %5, align 8, !tbaa !5
  %17 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %17, ptr %4, align 8, !tbaa !5
  %18 = load ptr, ptr %3, align 8, !tbaa !5
  %19 = getelementptr inbounds %class.ListNode, ptr %18, i32 0, i32 1
  %20 = load ptr, ptr %19, align 8, !tbaa !9
  store ptr %20, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #4
  %21 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %21, ptr %6, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #4
  %22 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %22, ptr %7, align 8, !tbaa !5
  br label %23

23:                                               ; preds = %35, %14
  %24 = load ptr, ptr %6, align 8, !tbaa !5
  %25 = getelementptr inbounds %class.ListNode, ptr %24, i32 0, i32 1
  %26 = load ptr, ptr %25, align 8, !tbaa !9
  %27 = icmp ne ptr %26, null
  br i1 %27, label %28, label %33

28:                                               ; preds = %23
  %29 = load ptr, ptr %7, align 8, !tbaa !5
  %30 = getelementptr inbounds %class.ListNode, ptr %29, i32 0, i32 1
  %31 = load ptr, ptr %30, align 8, !tbaa !9
  %32 = icmp ne ptr %31, null
  br label %33

33:                                               ; preds = %28, %23
  %34 = phi i1 [ false, %23 ], [ %32, %28 ]
  br i1 %34, label %35, label %56

35:                                               ; preds = %33
  %36 = load ptr, ptr %6, align 8, !tbaa !5
  %37 = getelementptr inbounds %class.ListNode, ptr %36, i32 0, i32 1
  %38 = load ptr, ptr %37, align 8, !tbaa !9
  %39 = getelementptr inbounds %class.ListNode, ptr %38, i32 0, i32 1
  %40 = load ptr, ptr %39, align 8, !tbaa !9
  %41 = load ptr, ptr %6, align 8, !tbaa !5
  %42 = getelementptr inbounds %class.ListNode, ptr %41, i32 0, i32 1
  store ptr %40, ptr %42, align 8, !tbaa !9
  %43 = load ptr, ptr %7, align 8, !tbaa !5
  %44 = getelementptr inbounds %class.ListNode, ptr %43, i32 0, i32 1
  %45 = load ptr, ptr %44, align 8, !tbaa !9
  %46 = getelementptr inbounds %class.ListNode, ptr %45, i32 0, i32 1
  %47 = load ptr, ptr %46, align 8, !tbaa !9
  %48 = load ptr, ptr %7, align 8, !tbaa !5
  %49 = getelementptr inbounds %class.ListNode, ptr %48, i32 0, i32 1
  store ptr %47, ptr %49, align 8, !tbaa !9
  %50 = load ptr, ptr %6, align 8, !tbaa !5
  %51 = getelementptr inbounds %class.ListNode, ptr %50, i32 0, i32 1
  %52 = load ptr, ptr %51, align 8, !tbaa !9
  store ptr %52, ptr %6, align 8, !tbaa !5
  %53 = load ptr, ptr %7, align 8, !tbaa !5
  %54 = getelementptr inbounds %class.ListNode, ptr %53, i32 0, i32 1
  %55 = load ptr, ptr %54, align 8, !tbaa !9
  store ptr %55, ptr %7, align 8, !tbaa !5
  br label %23, !llvm.loop !12

56:                                               ; preds = %33
  %57 = load ptr, ptr %5, align 8, !tbaa !5
  %58 = load ptr, ptr %6, align 8, !tbaa !5
  %59 = getelementptr inbounds %class.ListNode, ptr %58, i32 0, i32 1
  store ptr %57, ptr %59, align 8, !tbaa !9
  %60 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %60, ptr %2, align 8
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  br label %61

61:                                               ; preds = %56, %12
  %62 = load ptr, ptr %2, align 8
  ret ptr %62
}

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

; Function Attrs: nobuiltin allocsize(0)
declare noundef nonnull ptr @_Znwm(i64 noundef) #2

; Function Attrs: nocallback nofree nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #3

; 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 = { 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 #3 = { nocallback nofree nounwind willreturn memory(argmem: write) }
attributes #4 = { nounwind }
attributes #5 = { 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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !6, i64 8}
!10 = !{!"_ZTS8ListNode", !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"

; Function Attrs: mustprogress nofree norecurse nosync nounwind memory(readwrite, inaccessiblemem: none) uwtable
define dso_local noundef ptr @_Z20odd_even_linked_listP8ListNode(ptr noundef returned %0) local_unnamed_addr #0 {
  %2 = getelementptr inbounds i8, ptr %0, i64 8
  %3 = load ptr, ptr %2, align 8, !tbaa !5
  %4 = icmp eq ptr %3, null
  br i1 %4, label %18, label %.lr.ph

.lr.ph:                                           ; preds = %1, %9
  %5 = phi ptr [ %17, %9 ], [ %3, %1 ]
  %6 = phi ptr [ %16, %9 ], [ %2, %1 ]
  %.023 = phi ptr [ %14, %9 ], [ %3, %1 ]
  %7 = getelementptr inbounds i8, ptr %.023, i64 8
  %8 = load ptr, ptr %7, align 8, !tbaa !5
  %.not21 = icmp eq ptr %8, null
  br i1 %.not21, label %.critedge, label %9

9:                                                ; preds = %.lr.ph
  %10 = getelementptr inbounds i8, ptr %5, i64 8
  %11 = load ptr, ptr %10, align 8, !tbaa !5
  store ptr %11, ptr %6, align 8, !tbaa !5
  %12 = load ptr, ptr %7, align 8, !tbaa !5
  %13 = getelementptr inbounds i8, ptr %12, i64 8
  %14 = load ptr, ptr %13, align 8, !tbaa !5
  store ptr %14, ptr %7, align 8, !tbaa !5
  %15 = load ptr, ptr %6, align 8, !tbaa !5
  %16 = getelementptr inbounds i8, ptr %15, i64 8
  %17 = load ptr, ptr %16, align 8, !tbaa !5
  %.not = icmp eq ptr %17, null
  br i1 %.not, label %.critedge, label %.lr.ph, !llvm.loop !11

.critedge:                                        ; preds = %.lr.ph, %9
  %.lcssa.ph = phi ptr [ %6, %.lr.ph ], [ %16, %9 ]
  store ptr %3, ptr %.lcssa.ph, align 8, !tbaa !5
  br label %18

18:                                               ; preds = %1, %.critedge
  ret ptr %0
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind memory(readwrite, inaccessiblemem: none) 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 8}
!6 = !{!"_ZTS8ListNode", !7, i64 0, !10, i64 8}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}


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