; LLVM IR from UtkarshPathrabe/Competitive-Coding :: Stanford Competetive Programming/TDBFS.ll (Z3DFSi)

; 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::vector" = type { %"struct.std::_Vector_base" }
%"struct.std::_Vector_base" = type { %"struct.std::_Vector_base<Nodes, std::allocator<Nodes>>::_Vector_impl" }
%"struct.std::_Vector_base<Nodes, std::allocator<Nodes>>::_Vector_impl" = type { %"struct.std::_Vector_base<Nodes, std::allocator<Nodes>>::_Vector_impl_data" }
%"struct.std::_Vector_base<Nodes, std::allocator<Nodes>>::_Vector_impl_data" = type { ptr, ptr, ptr }
%struct.Nodes = type { i8, i32 }

@Node = external dso_local global %"class.std::vector", align 8
@n = external dso_local global i32, align 4

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

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorI5NodesSaIS0_EEixEm(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef) #1 align 2

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

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z10DFSUtilityiRSt6vectorI5NodesSaIS0_EE(i32 noundef, ptr noundef nonnull align 8 dereferenceable(24)) #2

; Function Attrs: mustprogress uwtable
define dso_local void @_Z3DFSi(i32 noundef %0) #2 {
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  store i32 %0, ptr %2, align 4, !tbaa !5
  %4 = call noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorI5NodesSaIS0_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) @Node, i64 noundef 0) #3
  %5 = getelementptr inbounds %struct.Nodes, ptr %4, i32 0, i32 0
  store i8 1, ptr %5, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #3
  store i32 1, ptr %3, align 4, !tbaa !5
  br label %6

6:                                                ; preds = %16, %1
  %7 = load i32, ptr %3, align 4, !tbaa !5
  %8 = load i32, ptr @n, align 4, !tbaa !5
  %9 = icmp sle i32 %7, %8
  br i1 %9, label %11, label %10

10:                                               ; preds = %6
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  br label %19

11:                                               ; preds = %6
  %12 = load i32, ptr %3, align 4, !tbaa !5
  %13 = sext i32 %12 to i64
  %14 = call noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorI5NodesSaIS0_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) @Node, i64 noundef %13) #3
  %15 = getelementptr inbounds %struct.Nodes, ptr %14, i32 0, i32 0
  store i8 0, ptr %15, align 4, !tbaa !9
  br label %16

16:                                               ; preds = %11
  %17 = load i32, ptr %3, align 4, !tbaa !5
  %18 = add nsw i32 %17, 1
  store i32 %18, ptr %3, align 4, !tbaa !5
  br label %6, !llvm.loop !12

19:                                               ; preds = %10
  %20 = load i32, ptr %2, align 4, !tbaa !5
  call void @_Z10DFSUtilityiRSt6vectorI5NodesSaIS0_EE(i32 noundef %20, ptr noundef nonnull align 8 dereferenceable(24) @Node)
  ret void
}

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 = { 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 }

!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, !11, i64 0}
!10 = !{!"_ZTS5Nodes", !11, i64 0, !6, i64 4}
!11 = !{!"bool", !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"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"

%"class.std::vector" = type { %"struct.std::_Vector_base" }
%"struct.std::_Vector_base" = type { %"struct.std::_Vector_base<Nodes, std::allocator<Nodes>>::_Vector_impl" }
%"struct.std::_Vector_base<Nodes, std::allocator<Nodes>>::_Vector_impl" = type { %"struct.std::_Vector_base<Nodes, std::allocator<Nodes>>::_Vector_impl_data" }
%"struct.std::_Vector_base<Nodes, std::allocator<Nodes>>::_Vector_impl_data" = type { ptr, ptr, ptr }

@Node = external dso_local global %"class.std::vector", align 8
@n = external dso_local local_unnamed_addr global i32, align 4

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorI5NodesSaIS0_EEixEm(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z10DFSUtilityiRSt6vectorI5NodesSaIS0_EE(i32 noundef, ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #1

; Function Attrs: mustprogress uwtable
define dso_local void @_Z3DFSi(i32 noundef %0) local_unnamed_addr #1 {
  %2 = tail call noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorI5NodesSaIS0_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) @Node, i64 noundef 0) #2
  store i8 1, ptr %2, align 4, !tbaa !5
  %3 = load i32, ptr @n, align 4, !tbaa !11
  %.not4 = icmp slt i32 %3, 1
  br i1 %.not4, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %.lr.ph, %1
  tail call void @_Z10DFSUtilityiRSt6vectorI5NodesSaIS0_EE(i32 noundef %0, ptr noundef nonnull align 8 dereferenceable(24) @Node)
  ret void

.lr.ph:                                           ; preds = %1, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 1, %1 ]
  %4 = tail call noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorI5NodesSaIS0_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) @Node, i64 noundef %indvars.iv) #2
  store i8 0, ptr %4, align 4, !tbaa !5
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %5 = load i32, ptr @n, align 4, !tbaa !11
  %6 = sext i32 %5 to i64
  %.not.not = icmp slt i64 %indvars.iv, %6
  br i1 %.not.not, label %.lr.ph, label %._crit_edge, !llvm.loop !12
}

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 = { 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 = { 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 = !{!"_ZTS5Nodes", !7, i64 0, !10, i64 4}
!7 = !{!"bool", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = !{!"int", !8, i64 0}
!11 = !{!10, !10, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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