; LLVM IR from VAR-solutions/Algorithms :: data structures/linked list/cpp/linked-list(doubly-singly).ll (Z9del_end_dv)

; 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.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }
%struct.node = type { i32, ptr, ptr }

@head = external dso_local global ptr, align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str.6 = external hidden unnamed_addr constant [21 x i8], align 1
@.str.7 = external hidden unnamed_addr constant [32 x i8], align 1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: inlinehint mustprogress uwtable
declare i32 @getchar() #1

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z6doublyv() #2

; Function Attrs: nounwind
declare void @free(ptr noundef) #3

; Function Attrs: mustprogress uwtable
define dso_local void @_Z9del_end_dv() #2 {
  %1 = alloca ptr, align 8
  %2 = alloca i32, align 4
  %3 = alloca ptr, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr %1) #4
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #4
  store i32 0, ptr %2, align 4, !tbaa !5
  %4 = load ptr, ptr @head, align 8, !tbaa !9
  store ptr %4, ptr %1, align 8, !tbaa !9
  %5 = load ptr, ptr @head, align 8, !tbaa !9
  %6 = icmp eq ptr %5, null
  br i1 %6, label %7, label %9

7:                                                ; preds = %0
  %8 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef @.str.6)
  br label %26

9:                                                ; preds = %0
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #4
  br label %10

10:                                               ; preds = %15, %9
  %11 = load ptr, ptr %1, align 8, !tbaa !9
  %12 = getelementptr inbounds %struct.node, ptr %11, i32 0, i32 1
  %13 = load ptr, ptr %12, align 8, !tbaa !11
  %14 = icmp ne ptr %13, null
  br i1 %14, label %15, label %19

15:                                               ; preds = %10
  %16 = load ptr, ptr %1, align 8, !tbaa !9
  %17 = getelementptr inbounds %struct.node, ptr %16, i32 0, i32 1
  %18 = load ptr, ptr %17, align 8, !tbaa !11
  store ptr %18, ptr %1, align 8, !tbaa !9
  br label %10, !llvm.loop !13

19:                                               ; preds = %10
  %20 = load ptr, ptr %1, align 8, !tbaa !9
  %21 = getelementptr inbounds %struct.node, ptr %20, i32 0, i32 2
  %22 = load ptr, ptr %21, align 8, !tbaa !15
  store ptr %22, ptr %3, align 8, !tbaa !9
  %23 = load ptr, ptr %1, align 8, !tbaa !9
  call void @free(ptr noundef %23) #4
  %24 = load ptr, ptr %3, align 8, !tbaa !9
  %25 = getelementptr inbounds %struct.node, ptr %24, i32 0, i32 1
  store ptr null, ptr %25, align 8, !tbaa !11
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #4
  br label %26

26:                                               ; preds = %19, %7
  %27 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef @.str.7)
  %28 = call i32 @getchar()
  call void @_Z6doublyv()
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %1) #4
  ret void
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { inlinehint 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 #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 "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 }

!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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !7, i64 0}
!11 = !{!12, !10, i64 8}
!12 = !{!"_ZTS4node", !6, i64 0, !10, i64 8, !10, i64 16}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}
!15 = !{!12, !10, i64 16}


; 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"

%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }

@head = external dso_local local_unnamed_addr global ptr, align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str.6 = external hidden unnamed_addr constant [21 x i8], align 1
@.str.7 = external hidden unnamed_addr constant [32 x i8], align 1

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #0

; Function Attrs: inlinehint mustprogress nofree nounwind uwtable
declare noundef i32 @getchar() local_unnamed_addr #1

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z6doublyv() local_unnamed_addr #2

; Function Attrs: mustprogress nounwind willreturn allockind("free") memory(argmem: readwrite, inaccessiblemem: readwrite)
declare void @free(ptr allocptr nocapture noundef) local_unnamed_addr #3

; Function Attrs: mustprogress uwtable
define dso_local void @_Z9del_end_dv() local_unnamed_addr #2 {
  %1 = load ptr, ptr @head, align 8, !tbaa !5
  %2 = icmp eq ptr %1, null
  br i1 %2, label %3, label %.preheader

3:                                                ; preds = %0
  %4 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef nonnull @.str.6)
  br label %11

.preheader:                                       ; preds = %0, %.preheader
  %.0 = phi ptr [ %6, %.preheader ], [ %1, %0 ]
  %5 = getelementptr inbounds i8, ptr %.0, i64 8
  %6 = load ptr, ptr %5, align 8, !tbaa !9
  %.not = icmp eq ptr %6, null
  br i1 %.not, label %7, label %.preheader, !llvm.loop !12

7:                                                ; preds = %.preheader
  %8 = getelementptr inbounds i8, ptr %.0, i64 16
  %9 = load ptr, ptr %8, align 8, !tbaa !14
  tail call void @free(ptr noundef nonnull %.0) #4
  %10 = getelementptr inbounds i8, ptr %9, i64 8
  store ptr null, ptr %10, align 8, !tbaa !9
  br label %11

11:                                               ; preds = %7, %3
  %12 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef nonnull @.str.7)
  %13 = tail call i32 @getchar()
  tail call void @_Z6doublyv()
  ret void
}

attributes #0 = { inlinehint 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 = { inlinehint mustprogress nofree 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 = { mustprogress nounwind willreturn allockind("free") memory(argmem: readwrite, inaccessiblemem: readwrite) "alloc-family"="malloc" "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 }

!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, !6, i64 16}
!11 = !{!"int", !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}
!14 = !{!10, !6, i64 16}


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