; LLVM IR from JessonYue/LeetCodeLearning :: Array/wuchao/tree/7-13 BST 转换为单链表 (BSTConvertToLinkedList)

; 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.TreeNode = type { i32, ptr, ptr }

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

8:                                                ; preds = %1
  store ptr null, ptr %2, align 8
  br label %43

9:                                                ; preds = %1
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #2
  %10 = load ptr, ptr %3, align 8, !tbaa !5
  %11 = getelementptr inbounds %struct.TreeNode, ptr %10, i32 0, i32 1
  %12 = load ptr, ptr %11, align 8, !tbaa !9
  %13 = call ptr @convertBiNode(ptr noundef %12)
  store ptr %13, ptr %4, align 8, !tbaa !5
  %14 = load ptr, ptr %3, align 8, !tbaa !5
  %15 = getelementptr inbounds %struct.TreeNode, ptr %14, i32 0, i32 1
  store ptr null, ptr %15, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #2
  %16 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %16, ptr %5, align 8, !tbaa !5
  %17 = load ptr, ptr %5, align 8, !tbaa !5
  %18 = icmp eq ptr %17, null
  br i1 %18, label %19, label %21

19:                                               ; preds = %9
  %20 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %20, ptr %5, align 8, !tbaa !5
  br label %35

21:                                               ; preds = %9
  br label %22

22:                                               ; preds = %27, %21
  %23 = load ptr, ptr %4, align 8, !tbaa !5
  %24 = getelementptr inbounds %struct.TreeNode, ptr %23, i32 0, i32 2
  %25 = load ptr, ptr %24, align 8, !tbaa !12
  %26 = icmp ne ptr %25, null
  br i1 %26, label %27, label %31

27:                                               ; preds = %22
  %28 = load ptr, ptr %4, align 8, !tbaa !5
  %29 = getelementptr inbounds %struct.TreeNode, ptr %28, i32 0, i32 2
  %30 = load ptr, ptr %29, align 8, !tbaa !12
  store ptr %30, ptr %4, align 8, !tbaa !5
  br label %22, !llvm.loop !13

31:                                               ; preds = %22
  %32 = load ptr, ptr %3, align 8, !tbaa !5
  %33 = load ptr, ptr %4, align 8, !tbaa !5
  %34 = getelementptr inbounds %struct.TreeNode, ptr %33, i32 0, i32 2
  store ptr %32, ptr %34, align 8, !tbaa !12
  br label %35

35:                                               ; preds = %31, %19
  %36 = load ptr, ptr %3, align 8, !tbaa !5
  %37 = getelementptr inbounds %struct.TreeNode, ptr %36, i32 0, i32 2
  %38 = load ptr, ptr %37, align 8, !tbaa !12
  %39 = call ptr @convertBiNode(ptr noundef %38)
  %40 = load ptr, ptr %3, align 8, !tbaa !5
  %41 = getelementptr inbounds %struct.TreeNode, ptr %40, i32 0, i32 2
  store ptr %39, ptr %41, align 8, !tbaa !12
  %42 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %42, ptr %2, align 8
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #2
  br label %43

43:                                               ; preds = %35, %8
  %44 = load ptr, ptr %2, align 8
  ret ptr %44
}

; 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

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 }

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

; Function Attrs: nofree nosync nounwind memory(readwrite, inaccessiblemem: none) uwtable
define dso_local ptr @convertBiNode(ptr noundef %0) local_unnamed_addr #0 {
  %2 = icmp eq ptr %0, null
  br i1 %2, label %common.ret19, label %3

3:                                                ; preds = %1
  %4 = getelementptr inbounds i8, ptr %0, i64 8
  %5 = load ptr, ptr %4, align 8, !tbaa !5
  %6 = tail call ptr @convertBiNode(ptr noundef %5)
  store ptr null, ptr %4, align 8, !tbaa !5
  %7 = icmp eq ptr %6, null
  br i1 %7, label %12, label %.preheader

.preheader:                                       ; preds = %3, %.preheader
  %.014 = phi ptr [ %9, %.preheader ], [ %6, %3 ]
  %8 = getelementptr inbounds i8, ptr %.014, i64 16
  %9 = load ptr, ptr %8, align 8, !tbaa !11
  %.not = icmp eq ptr %9, null
  br i1 %.not, label %10, label %.preheader, !llvm.loop !12

10:                                               ; preds = %.preheader
  %11 = getelementptr inbounds i8, ptr %.014, i64 16
  store ptr %0, ptr %11, align 8, !tbaa !11
  br label %12

common.ret19:                                     ; preds = %1, %12
  %common.ret19.op = phi ptr [ %.0, %12 ], [ null, %1 ]
  ret ptr %common.ret19.op

12:                                               ; preds = %3, %10
  %.0 = phi ptr [ %6, %10 ], [ %0, %3 ]
  %13 = getelementptr inbounds i8, ptr %0, i64 16
  %14 = load ptr, ptr %13, align 8, !tbaa !11
  %15 = tail call ptr @convertBiNode(ptr noundef %14)
  store ptr %15, ptr %13, align 8, !tbaa !11
  br label %common.ret19
}

attributes #0 = { nofree 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 = !{!"TreeNode", !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, !10, i64 16}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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