; LLVM IR from Chasmiccoder/Algos-for-Amigos :: Computer-Science/1-DSA-Fundamentals/2-Stacks-Queues-Linked-Lists/p05_linked_list_i_92d66b06 (listP4Node)

; 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"

%struct.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 uwtable
define dso_local noundef i32 @_Z18length_linked_listP4Node(ptr noundef %0) #0 {
  %2 = alloca ptr, align 8
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #4
  store i32 0, ptr %3, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  %5 = call noalias noundef nonnull ptr @_Znwm(i64 noundef 40) #5
  call void @_ZN4NodeC2Ev(ptr noundef nonnull align 8 dereferenceable(40) %5) #4
  store ptr %5, ptr %4, align 8, !tbaa !5
  %6 = load ptr, ptr %2, align 8, !tbaa !5
  store ptr %6, ptr %4, align 8, !tbaa !5
  br label %7

7:                                                ; preds = %12, %1
  %8 = load ptr, ptr %4, align 8, !tbaa !5
  %9 = getelementptr inbounds %struct.Node, ptr %8, i32 0, i32 1
  %10 = load ptr, ptr %9, align 8, !tbaa !11
  %11 = icmp ne ptr %10, null
  br i1 %11, label %12, label %18

12:                                               ; preds = %7
  %13 = load i32, ptr %3, align 4, !tbaa !9
  %14 = add nsw i32 %13, 1
  store i32 %14, ptr %3, align 4, !tbaa !9
  %15 = load ptr, ptr %4, align 8, !tbaa !5
  %16 = getelementptr inbounds %struct.Node, ptr %15, i32 0, i32 1
  %17 = load ptr, ptr %16, align 8, !tbaa !11
  store ptr %17, ptr %4, align 8, !tbaa !5
  br label %7, !llvm.loop !16

18:                                               ; preds = %7
  %19 = load i32, ptr %3, align 4, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #4
  ret i32 %19
}

; 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: inlinehint mustprogress nounwind uwtable
declare dso_local void @_ZN4NodeC2Ev(ptr noundef nonnull align 8 dereferenceable(40)) unnamed_addr #3 align 2

; 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 = { 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 #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, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{!12, !6, i64 32}
!12 = !{!"_ZTS4Node", !13, i64 0, !6, i64 32}
!13 = !{!"_ZTSNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE", !14, i64 0, !15, i64 8, !7, i64 16}
!14 = !{!"_ZTSNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE12_Alloc_hiderE", !6, i64 0}
!15 = !{!"long", !7, i64 0}
!16 = distinct !{!16, !17}
!17 = !{!"llvm.loop.mustprogress"}


; 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 noundef i32 @_Z18length_linked_listP4Node(ptr nocapture noundef readonly %0) local_unnamed_addr #0 {
  %2 = tail call noalias noundef nonnull dereferenceable(40) ptr @_Znwm(i64 noundef 40) #3
  tail call void @_ZN4NodeC2Ev(ptr noundef nonnull align 8 dereferenceable(40) %2) #4
  br label %3

3:                                                ; preds = %3, %1
  %.04 = phi i32 [ 0, %1 ], [ %6, %3 ]
  %.0 = phi ptr [ %0, %1 ], [ %5, %3 ]
  %4 = getelementptr inbounds i8, ptr %.0, i64 32
  %5 = load ptr, ptr %4, align 8, !tbaa !5
  %.not = icmp eq ptr %5, null
  %6 = add nuw nsw i32 %.04, 1
  br i1 %.not, label %7, label %3, !llvm.loop !13

7:                                                ; preds = %3
  ret i32 %.04
}

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

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local void @_ZN4NodeC2Ev(ptr noundef nonnull align 8 dereferenceable(40)) unnamed_addr #2 align 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 = { 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 = { builtin allocsize(0) }
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, !9, i64 32}
!6 = !{!"_ZTS4Node", !7, i64 0, !9, i64 32}
!7 = !{!"_ZTSNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE", !8, i64 0, !12, i64 8, !10, i64 16}
!8 = !{!"_ZTSNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE12_Alloc_hiderE", !9, i64 0}
!9 = !{!"any pointer", !10, i64 0}
!10 = !{!"omnipotent char", !11, i64 0}
!11 = !{!"Simple C++ TBAA"}
!12 = !{!"long", !10, i64 0}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LoopRotatePass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,TailCallElimPass