; LLVM IR from TheAlgorithms/C-Plus-Plus :: data_structures (reverse_a_linked_list)

; 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.data_structures::linked_list::Node" = type { i32, ptr }

; Function Attrs: mustprogress uwtable
define dso_local noundef ptr @_ZN15data_structures11linked_list14copy_all_nodesEPKNS0_4NodeE(ptr noundef %0) #0 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  store ptr %0, ptr %3, align 8, !tbaa !5
  %5 = load ptr, ptr %3, align 8, !tbaa !5
  %6 = icmp ne ptr %5, null
  br i1 %6, label %7, label %21

7:                                                ; preds = %1
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  %8 = call noalias noundef nonnull ptr @_Znwm(i64 noundef 16) #5
  call void @llvm.memset.p0.i64(ptr align 16 %8, i8 0, i64 16, i1 false)
  store ptr %8, ptr %4, align 8, !tbaa !5
  %9 = load ptr, ptr %3, align 8, !tbaa !5
  %10 = getelementptr inbounds %"class.data_structures::linked_list::Node", ptr %9, i32 0, i32 0
  %11 = load i32, ptr %10, align 8, !tbaa !9
  %12 = load ptr, ptr %4, align 8, !tbaa !5
  %13 = getelementptr inbounds %"class.data_structures::linked_list::Node", ptr %12, i32 0, i32 0
  store i32 %11, ptr %13, align 8, !tbaa !9
  %14 = load ptr, ptr %3, align 8, !tbaa !5
  %15 = getelementptr inbounds %"class.data_structures::linked_list::Node", ptr %14, i32 0, i32 1
  %16 = load ptr, ptr %15, align 8, !tbaa !12
  %17 = call noundef ptr @_ZN15data_structures11linked_list14copy_all_nodesEPKNS0_4NodeE(ptr noundef %16)
  %18 = load ptr, ptr %4, align 8, !tbaa !5
  %19 = getelementptr inbounds %"class.data_structures::linked_list::Node", ptr %18, i32 0, i32 1
  store ptr %17, ptr %19, align 8, !tbaa !12
  %20 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %20, ptr %2, align 8
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  br label %22

21:                                               ; preds = %1
  store ptr null, ptr %2, align 8
  br label %22

22:                                               ; preds = %21, %7
  %23 = load ptr, ptr %2, align 8
  ret ptr %23
}

; 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, !11, i64 0}
!10 = !{!"_ZTSN15data_structures11linked_list4NodeE", !11, i64 0, !6, i64 8}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !6, i64 8}


; 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 noalias noundef ptr @_ZN15data_structures11linked_list14copy_all_nodesEPKNS0_4NodeE(ptr noundef readonly %0) local_unnamed_addr #0 {
  %.not = icmp eq ptr %0, null
  br i1 %.not, label %common.ret8, label %2

common.ret8:                                      ; preds = %1, %2
  %common.ret8.op = phi ptr [ %3, %2 ], [ null, %1 ]
  ret ptr %common.ret8.op

2:                                                ; preds = %1
  %3 = tail call noalias noundef nonnull dereferenceable(16) ptr @_Znwm(i64 noundef 16) #3
  tail call void @llvm.memset.p0.i64(ptr noundef nonnull align 16 dereferenceable(16) %3, i8 0, i64 16, i1 false)
  %4 = load i32, ptr %0, align 8, !tbaa !5
  store i32 %4, ptr %3, align 8, !tbaa !5
  %5 = getelementptr inbounds i8, ptr %0, i64 8
  %6 = load ptr, ptr %5, align 8, !tbaa !11
  %7 = tail call noundef ptr @_ZN15data_structures11linked_list14copy_all_nodesEPKNS0_4NodeE(ptr noundef %6)
  %8 = getelementptr inbounds i8, ptr %3, i64 8
  store ptr %7, ptr %8, align 8, !tbaa !11
  br label %common.ret8
}

; Function Attrs: nobuiltin allocsize(0)
declare noundef nonnull ptr @_Znwm(i64 noundef) local_unnamed_addr #1

; Function Attrs: mustprogress nocallback nofree nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #2

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 = { 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 #2 = { mustprogress nocallback nofree nounwind willreturn memory(argmem: write) }
attributes #3 = { 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, !7, i64 0}
!6 = !{!"_ZTSN15data_structures11linked_list4NodeE", !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 = !{!6, !10, i64 8}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass