; LLVM IR from kmilo17pet/QuarkTS-cpp :: src/list.ll (ZN3qOS4list10removeBackEv)

; 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.qOS::list" = type { %"class.qOS::node", ptr, ptr, i64 }
%"class.qOS::node" = type { ptr, ptr, ptr, 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
define dso_local noundef ptr @_ZN3qOS4list10removeBackEv(ptr noundef nonnull align 8 dereferenceable(56) %0) #1 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) #2
  %5 = getelementptr inbounds %"class.qOS::list", ptr %4, i32 0, i32 2
  %6 = load ptr, ptr %5, align 8, !tbaa !9
  store ptr %6, ptr %3, align 8, !tbaa !5
  %7 = load ptr, ptr %3, align 8, !tbaa !5
  %8 = getelementptr inbounds %"class.qOS::node", ptr %7, i32 0, i32 2
  %9 = load ptr, ptr %8, align 8, !tbaa !13
  %10 = getelementptr inbounds %"class.qOS::list", ptr %4, i32 0, i32 2
  store ptr %9, ptr %10, align 8, !tbaa !9
  %11 = getelementptr inbounds %"class.qOS::list", ptr %4, i32 0, i32 2
  %12 = load ptr, ptr %11, align 8, !tbaa !9
  %13 = icmp eq ptr null, %12
  br i1 %13, label %14, label %18

14:                                               ; preds = %1
  %15 = getelementptr inbounds %"class.qOS::list", ptr %4, i32 0, i32 2
  %16 = load ptr, ptr %15, align 8, !tbaa !9
  %17 = getelementptr inbounds %"class.qOS::list", ptr %4, i32 0, i32 1
  store ptr %16, ptr %17, align 8, !tbaa !14
  br label %22

18:                                               ; preds = %1
  %19 = getelementptr inbounds %"class.qOS::list", ptr %4, i32 0, i32 2
  %20 = load ptr, ptr %19, align 8, !tbaa !9
  %21 = getelementptr inbounds %"class.qOS::node", ptr %20, i32 0, i32 1
  store ptr null, ptr %21, align 8, !tbaa !15
  br label %22

22:                                               ; preds = %18, %14
  %23 = load ptr, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #2
  ret ptr %23
}

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 = { 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 40}
!10 = !{!"_ZTSN3qOS4listE", !11, i64 0, !6, i64 32, !6, i64 40, !12, i64 48}
!11 = !{!"_ZTSN3qOS4nodeE", !6, i64 8, !6, i64 16, !6, i64 24}
!12 = !{!"long", !7, i64 0}
!13 = !{!11, !6, i64 16}
!14 = !{!10, !6, i64 32}
!15 = !{!11, !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 nofree norecurse nosync nounwind willreturn memory(readwrite, inaccessiblemem: none) uwtable
define dso_local noundef ptr @_ZN3qOS4list10removeBackEv(ptr nocapture noundef nonnull align 8 dereferenceable(56) %0) local_unnamed_addr #0 align 2 {
  %2 = getelementptr inbounds i8, ptr %0, i64 40
  %3 = load ptr, ptr %2, align 8, !tbaa !5
  %4 = getelementptr inbounds i8, ptr %3, i64 16
  %5 = load ptr, ptr %4, align 8, !tbaa !12
  store ptr %5, ptr %2, align 8, !tbaa !5
  %6 = icmp eq ptr %5, null
  %7 = getelementptr inbounds i8, ptr %5, i64 8
  %8 = getelementptr inbounds i8, ptr %0, i64 32
  %.sink = select i1 %6, ptr %8, ptr %7
  store ptr null, ptr %.sink, align 8, !tbaa !13
  ret ptr %3
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(readwrite, inaccessiblemem: none) 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, !8, i64 40}
!6 = !{!"_ZTSN3qOS4listE", !7, i64 0, !8, i64 32, !8, i64 40, !11, i64 48}
!7 = !{!"_ZTSN3qOS4nodeE", !8, i64 8, !8, i64 16, !8, i64 24}
!8 = !{!"any pointer", !9, i64 0}
!9 = !{!"omnipotent char", !10, i64 0}
!10 = !{!"Simple C++ TBAA"}
!11 = !{!"long", !9, i64 0}
!12 = !{!7, !8, i64 16}
!13 = !{!8, !8, i64 0}


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