; LLVM IR from div-bargali/Data-Structures-and-Algorithms :: C++/Data-Structures/LinkedList/OrderedLinkedListStrings.ll (ZN10sortedList9makeEmptyEv)

; 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.sortedList = type { ptr, i32, ptr }
%class.node = type { %"class.std::__cxx11::basic_string", ptr }
%"class.std::__cxx11::basic_string" = type { %"struct.std::__cxx11::basic_string<char>::_Alloc_hider", i64, %union.anon }
%"struct.std::__cxx11::basic_string<char>::_Alloc_hider" = type { ptr }
%union.anon = type { i64, [8 x i8] }

; Function Attrs: mustprogress nounwind uwtable
define dso_local void @_ZN10sortedList9makeEmptyEv(ptr noundef nonnull align 8 dereferenceable(24) %0) #0 align 2 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  store ptr %0, ptr %2, align 8, !tbaa !5
  %4 = load ptr, ptr %2, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #4
  br label %5

5:                                                ; preds = %20, %1
  %6 = getelementptr inbounds %class.sortedList, ptr %4, i32 0, i32 0
  %7 = load ptr, ptr %6, align 8, !tbaa !9
  %8 = icmp ne ptr %7, null
  br i1 %8, label %9, label %21

9:                                                ; preds = %5
  %10 = getelementptr inbounds %class.sortedList, ptr %4, i32 0, i32 0
  %11 = load ptr, ptr %10, align 8, !tbaa !9
  store ptr %11, ptr %3, align 8, !tbaa !5
  %12 = getelementptr inbounds %class.sortedList, ptr %4, i32 0, i32 0
  %13 = load ptr, ptr %12, align 8, !tbaa !9
  %14 = getelementptr inbounds %class.node, ptr %13, i32 0, i32 1
  %15 = load ptr, ptr %14, align 8, !tbaa !12
  %16 = getelementptr inbounds %class.sortedList, ptr %4, i32 0, i32 0
  store ptr %15, ptr %16, align 8, !tbaa !9
  %17 = load ptr, ptr %3, align 8, !tbaa !5
  %18 = icmp eq ptr %17, null
  br i1 %18, label %20, label %19

19:                                               ; preds = %9
  call void @_ZN4nodeD2Ev(ptr noundef nonnull align 8 dereferenceable(40) %17) #4
  call void @_ZdlPvm(ptr noundef %17, i64 noundef 40) #5
  br label %20

20:                                               ; preds = %19, %9
  br label %5, !llvm.loop !17

21:                                               ; preds = %5
  %22 = getelementptr inbounds %class.sortedList, ptr %4, i32 0, i32 1
  store i32 0, ptr %22, align 8, !tbaa !19
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #4
  ret void
}

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

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local void @_ZN4nodeD2Ev(ptr noundef nonnull align 8 dereferenceable(40)) unnamed_addr #2 align 2

; Function Attrs: nobuiltin nounwind
declare void @_ZdlPvm(ptr noundef, i64 noundef) #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 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 = { inlinehint 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 = { nobuiltin nounwind "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 #4 = { nounwind }
attributes #5 = { builtin 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 0}
!10 = !{!"_ZTS10sortedList", !6, i64 0, !11, i64 8, !6, i64 16}
!11 = !{!"int", !7, i64 0}
!12 = !{!13, !6, i64 32}
!13 = !{!"_ZTS4node", !14, i64 0, !6, i64 32}
!14 = !{!"_ZTSNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE", !15, i64 0, !16, i64 8, !7, i64 16}
!15 = !{!"_ZTSNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE12_Alloc_hiderE", !6, i64 0}
!16 = !{!"long", !7, i64 0}
!17 = distinct !{!17, !18}
!18 = !{!"llvm.loop.mustprogress"}
!19 = !{!10, !11, 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 nounwind uwtable
define dso_local void @_ZN10sortedList9makeEmptyEv(ptr nocapture noundef nonnull align 8 dereferenceable(24) %0) local_unnamed_addr #0 align 2 {
  %2 = load ptr, ptr %0, align 8, !tbaa !5
  %.not2 = icmp eq ptr %2, null
  br i1 %.not2, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %1, %.lr.ph
  %3 = phi ptr [ %6, %.lr.ph ], [ %2, %1 ]
  %4 = getelementptr inbounds i8, ptr %3, i64 32
  %5 = load ptr, ptr %4, align 8, !tbaa !11
  store ptr %5, ptr %0, align 8, !tbaa !5
  tail call void @_ZN4nodeD2Ev(ptr noundef nonnull align 8 dereferenceable(40) %3) #3
  tail call void @_ZdlPvm(ptr noundef nonnull %3, i64 noundef 40) #4
  %6 = load ptr, ptr %0, align 8, !tbaa !5
  %.not = icmp eq ptr %6, null
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !16

._crit_edge:                                      ; preds = %.lr.ph, %1
  %7 = getelementptr inbounds i8, ptr %0, i64 8
  store i32 0, ptr %7, align 8, !tbaa !18
  ret void
}

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local void @_ZN4nodeD2Ev(ptr noundef nonnull align 8 dereferenceable(40)) unnamed_addr #1 align 2

; Function Attrs: nobuiltin nounwind
declare void @_ZdlPvm(ptr noundef, i64 noundef) local_unnamed_addr #2

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 = { inlinehint 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 = { nobuiltin nounwind "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 }
attributes #4 = { builtin 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, !7, i64 0}
!6 = !{!"_ZTS10sortedList", !7, i64 0, !10, i64 8, !7, i64 16}
!7 = !{!"any pointer", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = !{!"int", !8, i64 0}
!11 = !{!12, !7, i64 32}
!12 = !{!"_ZTS4node", !13, i64 0, !7, i64 32}
!13 = !{!"_ZTSNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE", !14, i64 0, !15, i64 8, !8, i64 16}
!14 = !{!"_ZTSNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE12_Alloc_hiderE", !7, i64 0}
!15 = !{!"long", !8, i64 0}
!16 = distinct !{!16, !17}
!17 = !{!"llvm.loop.mustprogress"}
!18 = !{!6, !10, i64 8}


; Effective O3 passes: CorrelatedValuePropagationPass,EarlyCSEPass,GlobalOptPass,IPSCCPPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass