; LLVM IR from JessonYue/LeetCodeLearning :: Array/caiweixiong/cpp/Homework_007.ll (ZN12Homework_00713reverseList_1EP8ListNode)

; 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 @_ZN12Homework_00713reverseList_1EP8ListNode(ptr noundef nonnull align 1 dereferenceable(1) %0, ptr noundef %1) #0 align 2 {
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca %struct.ListNode, align 8
  %7 = alloca ptr, align 8
  store ptr %0, ptr %4, align 8, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !5
  %8 = load ptr, ptr %4, align 8
  %9 = load ptr, ptr %5, align 8, !tbaa !5
  %10 = icmp ne ptr %9, null
  br i1 %10, label %11, label %16

11:                                               ; preds = %2
  %12 = load ptr, ptr %5, align 8, !tbaa !5
  %13 = getelementptr inbounds %struct.ListNode, ptr %12, i32 0, i32 1
  %14 = load ptr, ptr %13, align 8, !tbaa !9
  %15 = icmp ne ptr %14, null
  br i1 %15, label %18, label %16

16:                                               ; preds = %11, %2
  %17 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %17, ptr %3, align 8
  br label %36

18:                                               ; preds = %11
  call void @llvm.lifetime.start.p0(i64 16, ptr %6) #3
  call void @_ZN8ListNodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16) %6, i32 noundef 0)
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #3
  br label %19

19:                                               ; preds = %22, %18
  %20 = load ptr, ptr %5, align 8, !tbaa !5
  %21 = icmp ne ptr %20, null
  br i1 %21, label %22, label %33

22:                                               ; preds = %19
  %23 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %23, ptr %7, align 8, !tbaa !5
  %24 = load ptr, ptr %5, align 8, !tbaa !5
  %25 = getelementptr inbounds %struct.ListNode, ptr %24, i32 0, i32 1
  %26 = load ptr, ptr %25, align 8, !tbaa !9
  store ptr %26, ptr %5, align 8, !tbaa !5
  %27 = getelementptr inbounds %struct.ListNode, ptr %6, i32 0, i32 1
  %28 = load ptr, ptr %27, align 8, !tbaa !9
  %29 = load ptr, ptr %7, align 8, !tbaa !5
  %30 = getelementptr inbounds %struct.ListNode, ptr %29, i32 0, i32 1
  store ptr %28, ptr %30, align 8, !tbaa !9
  %31 = load ptr, ptr %7, align 8, !tbaa !5
  %32 = getelementptr inbounds %struct.ListNode, ptr %6, i32 0, i32 1
  store ptr %31, ptr %32, align 8, !tbaa !9
  br label %19, !llvm.loop !12

33:                                               ; preds = %19
  %34 = getelementptr inbounds %struct.ListNode, ptr %6, i32 0, i32 1
  %35 = load ptr, ptr %34, align 8, !tbaa !9
  store ptr %35, ptr %3, align 8
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #3
  call void @llvm.lifetime.end.p0(i64 16, ptr %6) #3
  br label %36

36:                                               ; preds = %33, %16
  %37 = load ptr, ptr %3, align 8
  ret ptr %37
}

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

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZN8ListNodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16), i32 noundef) unnamed_addr #2 align 2

; 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 = { mustprogress 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++ 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"

%struct.ListNode = type { i32, ptr }

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef ptr @_ZN12Homework_00713reverseList_1EP8ListNode(ptr nocapture noundef nonnull readnone align 1 dereferenceable(1) %0, ptr noundef %1) local_unnamed_addr #0 align 2 {
  %3 = alloca %struct.ListNode, align 8
  %.not = icmp eq ptr %1, null
  br i1 %.not, label %15, label %4

4:                                                ; preds = %2
  %5 = getelementptr inbounds i8, ptr %1, i64 8
  %6 = load ptr, ptr %5, align 8, !tbaa !5
  %.not12 = icmp eq ptr %6, null
  br i1 %.not12, label %15, label %7

7:                                                ; preds = %4
  call void @llvm.lifetime.start.p0(i64 16, ptr nonnull %3) #2
  call void @_ZN8ListNodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16) %3, i32 noundef 0)
  %8 = getelementptr inbounds i8, ptr %3, i64 8
  %.pre = load ptr, ptr %8, align 8, !tbaa !5
  br label %9

9:                                                ; preds = %7, %9
  %10 = phi ptr [ %.pre, %7 ], [ %11, %9 ]
  %11 = phi ptr [ %1, %7 ], [ %13, %9 ]
  %12 = getelementptr inbounds i8, ptr %11, i64 8
  %13 = load ptr, ptr %12, align 8, !tbaa !5
  store ptr %10, ptr %12, align 8, !tbaa !5
  store ptr %11, ptr %8, align 8, !tbaa !5
  %.not13 = icmp eq ptr %13, null
  br i1 %.not13, label %14, label %9, !llvm.loop !11

14:                                               ; preds = %9
  call void @llvm.lifetime.end.p0(i64 16, ptr nonnull %3) #2
  br label %15

15:                                               ; preds = %2, %4, %14
  %.0 = phi ptr [ %11, %14 ], [ %1, %4 ], [ null, %2 ]
  ret ptr %.0
}

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

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZN8ListNodeC2Ei(ptr noundef nonnull align 8 dereferenceable(16), i32 noundef) unnamed_addr #0 align 2

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

attributes #0 = { mustprogress 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 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, !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: CorrelatedValuePropagationPass,EarlyCSEPass,GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LICMPass,LoopRotatePass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass