; LLVM IR from gargarchit/Data_Structure_n_Algorithms :: Linked_List/Implementation.ll (Z9mergesortP4Node)

; 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.Node = type { i32, ptr }

; 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

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef ptr @_Z8midpointRP4Node(ptr noundef nonnull align 8 dereferenceable(8)) #1

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_Z12merge2sortedP4NodeS0_(ptr noundef, ptr noundef) #2

; Function Attrs: mustprogress uwtable
define dso_local noundef ptr @_Z9mergesortP4Node(ptr noundef %0) #2 {
  %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 = icmp eq ptr %8, null
  br i1 %9, label %15, label %10

10:                                               ; preds = %1
  %11 = load ptr, ptr %3, align 8, !tbaa !5
  %12 = getelementptr inbounds %class.Node, ptr %11, i32 0, i32 1
  %13 = load ptr, ptr %12, align 8, !tbaa !9
  %14 = icmp eq ptr %13, null
  br i1 %14, label %15, label %17

15:                                               ; preds = %10, %1
  %16 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %16, ptr %2, align 8
  br label %33

17:                                               ; preds = %10
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #3
  %18 = call noundef ptr @_Z8midpointRP4Node(ptr noundef nonnull align 8 dereferenceable(8) %3)
  store ptr %18, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #3
  %19 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %19, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #3
  %20 = load ptr, ptr %4, align 8, !tbaa !5
  %21 = getelementptr inbounds %class.Node, ptr %20, i32 0, i32 1
  %22 = load ptr, ptr %21, align 8, !tbaa !9
  store ptr %22, ptr %6, align 8, !tbaa !5
  %23 = load ptr, ptr %4, align 8, !tbaa !5
  %24 = getelementptr inbounds %class.Node, ptr %23, i32 0, i32 1
  store ptr null, ptr %24, align 8, !tbaa !9
  %25 = load ptr, ptr %5, align 8, !tbaa !5
  %26 = call noundef ptr @_Z9mergesortP4Node(ptr noundef %25)
  store ptr %26, ptr %5, align 8, !tbaa !5
  %27 = load ptr, ptr %6, align 8, !tbaa !5
  %28 = call noundef ptr @_Z9mergesortP4Node(ptr noundef %27)
  store ptr %28, ptr %6, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #3
  %29 = load ptr, ptr %5, align 8, !tbaa !5
  %30 = load ptr, ptr %6, align 8, !tbaa !5
  %31 = call noundef ptr @_Z12merge2sortedP4NodeS0_(ptr noundef %29, ptr noundef %30)
  store ptr %31, ptr %7, align 8, !tbaa !5
  %32 = load ptr, ptr %7, align 8, !tbaa !5
  store ptr %32, ptr %2, align 8
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #3
  br label %33

33:                                               ; preds = %17, %15
  %34 = load ptr, ptr %2, align 8
  ret ptr %34
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #2 = { 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 #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 = !{!"_ZTS4Node", !11, i64 0, !6, i64 8}
!11 = !{!"int", !7, i64 0}


; 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 nounwind uwtable
declare dso_local noundef ptr @_Z8midpointRP4Node(ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #0

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_Z12merge2sortedP4NodeS0_(ptr noundef, ptr noundef) local_unnamed_addr #1

; Function Attrs: mustprogress uwtable
define dso_local noundef ptr @_Z9mergesortP4Node(ptr noundef %0) local_unnamed_addr #1 {
  %2 = alloca ptr, align 8
  store ptr %0, ptr %2, align 8, !tbaa !5
  %3 = icmp eq ptr %0, null
  br i1 %3, label %16, label %4

4:                                                ; preds = %1
  %5 = getelementptr inbounds i8, ptr %0, i64 8
  %6 = load ptr, ptr %5, align 8, !tbaa !9
  %7 = icmp eq ptr %6, null
  br i1 %7, label %16, label %8

8:                                                ; preds = %4
  %9 = call noundef ptr @_Z8midpointRP4Node(ptr noundef nonnull align 8 dereferenceable(8) %2)
  %10 = load ptr, ptr %2, align 8, !tbaa !5
  %11 = getelementptr inbounds i8, ptr %9, i64 8
  %12 = load ptr, ptr %11, align 8, !tbaa !9
  store ptr null, ptr %11, align 8, !tbaa !9
  %13 = call noundef ptr @_Z9mergesortP4Node(ptr noundef %10)
  %14 = call noundef ptr @_Z9mergesortP4Node(ptr noundef %12)
  %15 = call noundef ptr @_Z12merge2sortedP4NodeS0_(ptr noundef %13, ptr noundef %14)
  br label %16

16:                                               ; preds = %1, %4, %8
  %.0 = phi ptr [ %15, %8 ], [ %0, %4 ], [ null, %1 ]
  ret ptr %.0
}

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 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, !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 = !{!"_ZTS4Node", !11, i64 0, !6, i64 8}
!11 = !{!"int", !7, i64 0}


; Effective O3 passes: CorrelatedValuePropagationPass,EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,SROAPass