; LLVM IR from JessonYue/LeetCodeLearning :: Array/zhanchengguo/0728-排序链表/LinkedSort.ll (Z8sortListP8ListNode)

; 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.ListNode = type { i32, ptr }

; Function Attrs: mustprogress uwtable
define dso_local noundef ptr @_Z8sortListP8ListNode(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
  store ptr %0, ptr %3, align 8, !tbaa !5
  %7 = load ptr, ptr %3, align 8, !tbaa !5
  %8 = icmp eq ptr %7, null
  br i1 %8, label %14, label %9

9:                                                ; preds = %1
  %10 = load ptr, ptr %3, align 8, !tbaa !5
  %11 = getelementptr inbounds %struct.ListNode, ptr %10, i32 0, i32 1
  %12 = load ptr, ptr %11, align 8, !tbaa !9
  %13 = icmp eq ptr %12, null
  br i1 %13, label %14, label %16

14:                                               ; preds = %9, %1
  %15 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %15, ptr %2, align 8
  br label %47

16:                                               ; preds = %9
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #2
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #2
  %17 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %17, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #2
  %18 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %18, ptr %6, align 8, !tbaa !5
  br label %19

19:                                               ; preds = %29, %16
  %20 = load ptr, ptr %6, align 8, !tbaa !5
  %21 = icmp ne ptr %20, null
  br i1 %21, label %22, label %27

22:                                               ; preds = %19
  %23 = load ptr, ptr %6, align 8, !tbaa !5
  %24 = getelementptr inbounds %struct.ListNode, ptr %23, i32 0, i32 1
  %25 = load ptr, ptr %24, align 8, !tbaa !9
  %26 = icmp ne ptr %25, null
  br label %27

27:                                               ; preds = %22, %19
  %28 = phi i1 [ false, %19 ], [ %26, %22 ]
  br i1 %28, label %29, label %39

29:                                               ; preds = %27
  %30 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %30, ptr %4, align 8, !tbaa !5
  %31 = load ptr, ptr %5, align 8, !tbaa !5
  %32 = getelementptr inbounds %struct.ListNode, ptr %31, i32 0, i32 1
  %33 = load ptr, ptr %32, align 8, !tbaa !9
  store ptr %33, ptr %5, align 8, !tbaa !5
  %34 = load ptr, ptr %6, align 8, !tbaa !5
  %35 = getelementptr inbounds %struct.ListNode, ptr %34, i32 0, i32 1
  %36 = load ptr, ptr %35, align 8, !tbaa !9
  %37 = getelementptr inbounds %struct.ListNode, ptr %36, i32 0, i32 1
  %38 = load ptr, ptr %37, align 8, !tbaa !9
  store ptr %38, ptr %6, align 8, !tbaa !5
  br label %19, !llvm.loop !12

39:                                               ; preds = %27
  %40 = load ptr, ptr %4, align 8, !tbaa !5
  %41 = getelementptr inbounds %struct.ListNode, ptr %40, i32 0, i32 1
  store ptr null, ptr %41, align 8, !tbaa !9
  %42 = load ptr, ptr %3, align 8, !tbaa !5
  %43 = call noundef ptr @_Z8sortListP8ListNode(ptr noundef %42)
  %44 = load ptr, ptr %5, align 8, !tbaa !5
  %45 = call noundef ptr @_Z8sortListP8ListNode(ptr noundef %44)
  %46 = call noundef ptr @_Z11twoWayMergeP8ListNodeS0_(ptr noundef %43, ptr noundef %45)
  store ptr %46, ptr %2, align 8
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #2
  br label %47

47:                                               ; preds = %39, %14
  %48 = load ptr, ptr %2, align 8
  ret ptr %48
}

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

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_Z11twoWayMergeP8ListNodeS0_(ptr noundef, ptr noundef) #0

; 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 = { 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++ 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 uwtable
define dso_local noundef ptr @_Z8sortListP8ListNode(ptr noundef %0) local_unnamed_addr #0 {
  %2 = icmp eq ptr %0, null
  br i1 %2, label %common.ret28, 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, null
  br i1 %6, label %common.ret28, label %.preheader.preheader

.preheader.preheader:                             ; preds = %3
  %7 = getelementptr inbounds i8, ptr %0, i64 8
  %8 = load ptr, ptr %7, align 8, !tbaa !5, !nonnull !11, !noundef !11
  br label %.lr.ph

.preheader:                                       ; preds = %.lr.ph
  %9 = getelementptr inbounds i8, ptr %15, i64 8
  %10 = load ptr, ptr %9, align 8, !tbaa !5
  %.not19 = icmp eq ptr %10, null
  br i1 %.not19, label %.critedge, label %.lr.ph, !llvm.loop !12

.lr.ph:                                           ; preds = %.preheader.preheader, %.preheader
  %11 = phi ptr [ %10, %.preheader ], [ %8, %.preheader.preheader ]
  %.0142124 = phi ptr [ %13, %.preheader ], [ %0, %.preheader.preheader ]
  %12 = getelementptr inbounds i8, ptr %.0142124, i64 8
  %13 = load ptr, ptr %12, align 8, !tbaa !5
  %14 = getelementptr inbounds i8, ptr %11, i64 8
  %15 = load ptr, ptr %14, align 8, !tbaa !5
  %.not = icmp eq ptr %15, null
  br i1 %.not, label %.critedge, label %.preheader, !llvm.loop !12

common.ret28:                                     ; preds = %1, %3, %.critedge
  %common.ret28.op = phi ptr [ %19, %.critedge ], [ %0, %3 ], [ null, %1 ]
  ret ptr %common.ret28.op

.critedge:                                        ; preds = %.preheader, %.lr.ph
  %16 = getelementptr inbounds i8, ptr %.0142124, i64 8
  store ptr null, ptr %16, align 8, !tbaa !5
  %17 = tail call noundef ptr @_Z8sortListP8ListNode(ptr noundef nonnull %0)
  %18 = tail call noundef ptr @_Z8sortListP8ListNode(ptr noundef %13)
  %19 = tail call noundef ptr @_Z11twoWayMergeP8ListNodeS0_(ptr noundef %17, ptr noundef %18)
  br label %common.ret28
}

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_Z11twoWayMergeP8ListNodeS0_(ptr noundef, ptr noundef) local_unnamed_addr #0

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" }

!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 = !{}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: CorrelatedValuePropagationPass,EarlyCSEPass,GlobalDCEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass,TailCallElimPass