; LLVM IR from eyangch/competitive-programming :: CSES/Introductory_Problems (chessboard_and_queens)

; 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::__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] }
%"class.std::basic_istream" = type { ptr, i64, %"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 }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }

@_Z2cbB5cxx11 = external dso_local global [8 x %"class.std::__cxx11::basic_string"], align 16
@ans = external dso_local global i32, align 4
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z3dfsiiiii(i32 noundef, i32 noundef, i32 noundef, i32 noundef, i32 noundef) #0

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

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

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #2 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  %4 = call noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext false)
  %5 = load ptr, ptr @_ZSt3cin, align 8, !tbaa !5
  %6 = getelementptr i8, ptr %5, i64 -24
  %7 = load i64, ptr %6, align 8
  %8 = getelementptr inbounds i8, ptr @_ZSt3cin, i64 %7
  %9 = call noundef ptr @_ZNSt9basic_iosIcSt11char_traitsIcEE3tieEPSo(ptr noundef nonnull align 8 dereferenceable(264) %8, ptr noundef null)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #6
  store i32 0, ptr %2, align 4, !tbaa !8
  br label %10

10:                                               ; preds = %19, %0
  %11 = load i32, ptr %2, align 4, !tbaa !8
  %12 = icmp slt i32 %11, 8
  br i1 %12, label %14, label %13

13:                                               ; preds = %10
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #6
  br label %22

14:                                               ; preds = %10
  %15 = load i32, ptr %2, align 4, !tbaa !8
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds [8 x %"class.std::__cxx11::basic_string"], ptr @_Z2cbB5cxx11, i64 0, i64 %16
  %18 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RNSt7__cxx1112basic_stringIS4_S5_T1_EE(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(32) %17)
  br label %19

19:                                               ; preds = %14
  %20 = load i32, ptr %2, align 4, !tbaa !8
  %21 = add nsw i32 %20, 1
  store i32 %21, ptr %2, align 4, !tbaa !8
  br label %10, !llvm.loop !11

22:                                               ; preds = %13
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #6
  store i32 0, ptr %3, align 4, !tbaa !8
  br label %23

23:                                               ; preds = %29, %22
  %24 = load i32, ptr %3, align 4, !tbaa !8
  %25 = icmp slt i32 %24, 8
  br i1 %25, label %27, label %26

26:                                               ; preds = %23
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #6
  br label %32

27:                                               ; preds = %23
  %28 = load i32, ptr %3, align 4, !tbaa !8
  call void @_Z3dfsiiiii(i32 noundef %28, i32 noundef 0, i32 noundef 0, i32 noundef 0, i32 noundef 0)
  br label %29

29:                                               ; preds = %27
  %30 = load i32, ptr %3, align 4, !tbaa !8
  %31 = add nsw i32 %30, 1
  store i32 %31, ptr %3, align 4, !tbaa !8
  br label %23, !llvm.loop !13

32:                                               ; preds = %26
  %33 = load i32, ptr @ans, align 4, !tbaa !8
  %34 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %33)
  %35 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %34, ptr noundef @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  ret i32 0
}

declare noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext) #3

; Function Attrs: mustprogress nounwind uwtable
declare noundef ptr @_ZNSt9basic_iosIcSt11char_traitsIcEE3tieEPSo(ptr noundef nonnull align 8 dereferenceable(264), ptr noundef) #4 align 2

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RNSt7__cxx1112basic_stringIS4_S5_T1_EE(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 8 dereferenceable(32)) #3

declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) #3

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #0 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_(ptr noundef nonnull align 8 dereferenceable(8)) #5

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 = { mustprogress norecurse 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 = { "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 = { 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 #5 = { 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 #6 = { 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 = !{!"vtable pointer", !7, i64 0}
!7 = !{!"Simple C++ TBAA"}
!8 = !{!9, !9, i64 0}
!9 = !{!"int", !10, i64 0}
!10 = !{!"omnipotent char", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = distinct !{!13, !12}


; 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::__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] }
%"class.std::basic_istream" = type { ptr, i64, %"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 }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }

@_Z2cbB5cxx11 = external dso_local global [8 x %"class.std::__cxx11::basic_string"], align 16
@ans = external dso_local local_unnamed_addr global i32, align 4
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z3dfsiiiii(i32 noundef, i32 noundef, i32 noundef, i32 noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #1 {
.preheader.preheader:
  %0 = tail call noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext false)
  %1 = load ptr, ptr @_ZSt3cin, align 8, !tbaa !5
  %2 = getelementptr i8, ptr %1, i64 -24
  %3 = load i64, ptr %2, align 8
  %4 = getelementptr inbounds i8, ptr @_ZSt3cin, i64 %3
  %5 = tail call noundef ptr @_ZNSt9basic_iosIcSt11char_traitsIcEE3tieEPSo(ptr noundef nonnull align 8 dereferenceable(264) %4, ptr noundef null)
  %6 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RNSt7__cxx1112basic_stringIS4_S5_T1_EE(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(32) @_Z2cbB5cxx11)
  %7 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RNSt7__cxx1112basic_stringIS4_S5_T1_EE(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(32) getelementptr inbounds (i8, ptr @_Z2cbB5cxx11, i64 32))
  %8 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RNSt7__cxx1112basic_stringIS4_S5_T1_EE(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(32) getelementptr inbounds (i8, ptr @_Z2cbB5cxx11, i64 64))
  %9 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RNSt7__cxx1112basic_stringIS4_S5_T1_EE(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(32) getelementptr inbounds (i8, ptr @_Z2cbB5cxx11, i64 96))
  %10 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RNSt7__cxx1112basic_stringIS4_S5_T1_EE(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(32) getelementptr inbounds (i8, ptr @_Z2cbB5cxx11, i64 128))
  %11 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RNSt7__cxx1112basic_stringIS4_S5_T1_EE(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(32) getelementptr inbounds (i8, ptr @_Z2cbB5cxx11, i64 160))
  %12 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RNSt7__cxx1112basic_stringIS4_S5_T1_EE(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(32) getelementptr inbounds (i8, ptr @_Z2cbB5cxx11, i64 192))
  %13 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RNSt7__cxx1112basic_stringIS4_S5_T1_EE(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(32) getelementptr inbounds (i8, ptr @_Z2cbB5cxx11, i64 224))
  tail call void @_Z3dfsiiiii(i32 noundef 0, i32 noundef 0, i32 noundef 0, i32 noundef 0, i32 noundef 0)
  tail call void @_Z3dfsiiiii(i32 noundef 1, i32 noundef 0, i32 noundef 0, i32 noundef 0, i32 noundef 0)
  tail call void @_Z3dfsiiiii(i32 noundef 2, i32 noundef 0, i32 noundef 0, i32 noundef 0, i32 noundef 0)
  tail call void @_Z3dfsiiiii(i32 noundef 3, i32 noundef 0, i32 noundef 0, i32 noundef 0, i32 noundef 0)
  tail call void @_Z3dfsiiiii(i32 noundef 4, i32 noundef 0, i32 noundef 0, i32 noundef 0, i32 noundef 0)
  tail call void @_Z3dfsiiiii(i32 noundef 5, i32 noundef 0, i32 noundef 0, i32 noundef 0, i32 noundef 0)
  tail call void @_Z3dfsiiiii(i32 noundef 6, i32 noundef 0, i32 noundef 0, i32 noundef 0, i32 noundef 0)
  tail call void @_Z3dfsiiiii(i32 noundef 7, i32 noundef 0, i32 noundef 0, i32 noundef 0, i32 noundef 0)
  %14 = load i32, ptr @ans, align 4, !tbaa !8
  %15 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %14)
  %16 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %15, ptr noundef nonnull @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  ret i32 0
}

declare noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext) local_unnamed_addr #2

; Function Attrs: mustprogress nounwind uwtable
declare noundef ptr @_ZNSt9basic_iosIcSt11char_traitsIcEE3tieEPSo(ptr noundef nonnull align 8 dereferenceable(264), ptr noundef) local_unnamed_addr #3 align 2

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RNSt7__cxx1112basic_stringIS4_S5_T1_EE(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 8 dereferenceable(32)) local_unnamed_addr #2

declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) local_unnamed_addr #2

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #0 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_(ptr noundef nonnull align 8 dereferenceable(8)) #4

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 = { mustprogress norecurse 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 = { "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 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 = { 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" }

!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 = !{!"vtable pointer", !7, i64 0}
!7 = !{!"Simple C++ TBAA"}
!8 = !{!9, !9, i64 0}
!9 = !{!"int", !10, i64 0}
!10 = !{!"omnipotent char", !7, i64 0}


; Effective O3 passes: GVNPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,LoopRotatePass,LoopSimplifyPass,SROAPass,SimplifyCFGPass,TailCallElimPass