; LLVM IR from Tunghohin/Competitive_Coding :: Uva (uva11401)

; 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_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" }

@f = external dso_local global [1000010 x i64], align 16
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #5
  store i32 4, ptr %2, align 4, !tbaa !5
  br label %5

5:                                                ; preds = %33, %0
  %6 = load i32, ptr %2, align 4, !tbaa !5
  %7 = icmp sle i32 %6, 1000000
  br i1 %7, label %9, label %8

8:                                                ; preds = %5
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #5
  br label %36

9:                                                ; preds = %5
  %10 = load i32, ptr %2, align 4, !tbaa !5
  %11 = sub nsw i32 %10, 1
  %12 = sext i32 %11 to i64
  %13 = getelementptr inbounds [1000010 x i64], ptr @f, i64 0, i64 %12
  %14 = load i64, ptr %13, align 8, !tbaa !9
  %15 = load i32, ptr %2, align 4, !tbaa !5
  %16 = sub nsw i32 %15, 1
  %17 = sext i32 %16 to i64
  %18 = load i32, ptr %2, align 4, !tbaa !5
  %19 = sub nsw i32 %18, 2
  %20 = sext i32 %19 to i64
  %21 = mul i64 %17, %20
  %22 = udiv i64 %21, 2
  %23 = load i32, ptr %2, align 4, !tbaa !5
  %24 = sub nsw i32 %23, 1
  %25 = sdiv i32 %24, 2
  %26 = sext i32 %25 to i64
  %27 = sub i64 %22, %26
  %28 = udiv i64 %27, 2
  %29 = add i64 %14, %28
  %30 = load i32, ptr %2, align 4, !tbaa !5
  %31 = sext i32 %30 to i64
  %32 = getelementptr inbounds [1000010 x i64], ptr @f, i64 0, i64 %31
  store i64 %29, ptr %32, align 8, !tbaa !9
  br label %33

33:                                               ; preds = %9
  %34 = load i32, ptr %2, align 4, !tbaa !5
  %35 = add nsw i32 %34, 1
  store i32 %35, ptr %2, align 4, !tbaa !5
  br label %5, !llvm.loop !11

36:                                               ; preds = %8
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #5
  br label %37

37:                                               ; preds = %48, %36
  %38 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %3)
  %39 = load ptr, ptr %38, align 8, !tbaa !13
  %40 = getelementptr i8, ptr %39, i64 -24
  %41 = load i64, ptr %40, align 8
  %42 = getelementptr inbounds i8, ptr %38, i64 %41
  %43 = call noundef zeroext i1 @_ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv(ptr noundef nonnull align 8 dereferenceable(264) %42)
  br i1 %43, label %44, label %55

44:                                               ; preds = %37
  %45 = load i32, ptr %3, align 4, !tbaa !5
  %46 = icmp slt i32 %45, 3
  br i1 %46, label %47, label %48

47:                                               ; preds = %44
  store i32 0, ptr %1, align 4
  store i32 1, ptr %4, align 4
  br label %56

48:                                               ; preds = %44
  %49 = load i32, ptr %3, align 4, !tbaa !5
  %50 = sext i32 %49 to i64
  %51 = getelementptr inbounds [1000010 x i64], ptr @f, i64 0, i64 %50
  %52 = load i64, ptr %51, align 8, !tbaa !9
  %53 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEy(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i64 noundef %52)
  %54 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_c(ptr noundef nonnull align 8 dereferenceable(8) %53, i8 noundef signext 10)
  br label %37, !llvm.loop !15

55:                                               ; preds = %37
  store i32 0, ptr %4, align 4
  br label %56

56:                                               ; preds = %55, %47
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #5
  %57 = load i32, ptr %4, align 4
  switch i32 %57, label %60 [
    i32 0, label %58
    i32 1, label %58
  ]

58:                                               ; preds = %56, %56
  %59 = load i32, ptr %1, align 4
  ret i32 %59

60:                                               ; preds = %56
  unreachable
}

; 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

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) #2

; Function Attrs: mustprogress uwtable
declare noundef zeroext i1 @_ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv(ptr noundef nonnull align 8 dereferenceable(264)) #3 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_c(ptr noundef nonnull align 8 dereferenceable(8), i8 noundef signext) #4

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEy(ptr noundef nonnull align 8 dereferenceable(8), i64 noundef) #3 align 2

attributes #0 = { 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 #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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 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" }
attributes #5 = { 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 = !{!"long long", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = !{!14, !14, i64 0}
!14 = !{!"vtable pointer", !8, i64 0}
!15 = distinct !{!15, !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::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" }

@f = external dso_local local_unnamed_addr global [1000010 x i64], align 16
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = alloca i32, align 4
  %.pre = load i64, ptr getelementptr inbounds (i8, ptr @f, i64 24), align 8, !tbaa !5
  br label %9

2:                                                ; preds = %9
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #5
  %3 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %1)
  %4 = load ptr, ptr %3, align 8, !tbaa !9
  %5 = getelementptr i8, ptr %4, i64 -24
  %6 = load i64, ptr %5, align 8
  %7 = getelementptr inbounds i8, ptr %3, i64 %6
  %8 = call noundef zeroext i1 @_ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv(ptr noundef nonnull align 8 dereferenceable(264) %7)
  br i1 %8, label %.lr.ph, label %._crit_edge

9:                                                ; preds = %19, %0
  %10 = phi i64 [ %.pre, %0 ], [ %25, %19 ]
  %indvars.iv = phi i64 [ 4, %0 ], [ %indvars.iv.next.1, %19 ]
  %11 = add nsw i64 %indvars.iv, -1
  %12 = add nsw i64 %indvars.iv, -2
  %13 = mul nsw i64 %11, %12
  %14 = lshr exact i64 %13, 1
  %.udiv13 = lshr i64 %11, 1
  %15 = sub nsw i64 %14, %.udiv13
  %16 = lshr i64 %15, 1
  %17 = add i64 %10, %16
  %18 = getelementptr inbounds [1000010 x i64], ptr @f, i64 0, i64 %indvars.iv
  store i64 %17, ptr %18, align 16, !tbaa !5
  %exitcond.not = icmp eq i64 %indvars.iv, 1000000
  br i1 %exitcond.not, label %2, label %19, !llvm.loop !11

19:                                               ; preds = %9
  %indvars.iv.next = or disjoint i64 %indvars.iv, 1
  %20 = add nsw i64 %indvars.iv, -1
  %21 = mul nsw i64 %indvars.iv, %20
  %22 = lshr exact i64 %21, 1
  %.udiv13.1 = lshr exact i64 %indvars.iv, 1
  %23 = sub nsw i64 %22, %.udiv13.1
  %24 = lshr i64 %23, 1
  %25 = add i64 %17, %24
  %26 = getelementptr inbounds [1000010 x i64], ptr @f, i64 0, i64 %indvars.iv.next
  store i64 %25, ptr %26, align 8, !tbaa !5
  %indvars.iv.next.1 = add nuw nsw i64 %indvars.iv, 2
  br label %9

.lr.ph:                                           ; preds = %2, %29
  %27 = load i32, ptr %1, align 4, !tbaa !13
  %28 = icmp slt i32 %27, 3
  br i1 %28, label %._crit_edge, label %29

29:                                               ; preds = %.lr.ph
  %30 = zext nneg i32 %27 to i64
  %31 = getelementptr inbounds [1000010 x i64], ptr @f, i64 0, i64 %30
  %32 = load i64, ptr %31, align 8, !tbaa !5
  %33 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEy(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i64 noundef %32)
  %34 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_c(ptr noundef nonnull align 8 dereferenceable(8) %33, i8 noundef signext 10)
  %35 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %1)
  %36 = load ptr, ptr %35, align 8, !tbaa !9
  %37 = getelementptr i8, ptr %36, i64 -24
  %38 = load i64, ptr %37, align 8
  %39 = getelementptr inbounds i8, ptr %35, i64 %38
  %40 = call noundef zeroext i1 @_ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv(ptr noundef nonnull align 8 dereferenceable(264) %39)
  br i1 %40, label %.lr.ph, label %._crit_edge, !llvm.loop !15

._crit_edge:                                      ; preds = %.lr.ph, %29, %2
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #5
  ret i32 0
}

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

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

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #2

; Function Attrs: mustprogress uwtable
declare noundef zeroext i1 @_ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv(ptr noundef nonnull align 8 dereferenceable(264)) local_unnamed_addr #3 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_c(ptr noundef nonnull align 8 dereferenceable(8), i8 noundef signext) local_unnamed_addr #4

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEy(ptr noundef nonnull align 8 dereferenceable(8), i64 noundef) local_unnamed_addr #3 align 2

attributes #0 = { 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 #1 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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 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" }
attributes #5 = { 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 = !{!"long long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"vtable pointer", !8, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = !{!14, !14, i64 0}
!14 = !{!"int", !7, i64 0}
!15 = distinct !{!15, !12}


; Effective O3 passes: BDCEPass,CorrelatedValuePropagationPass,EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferAlignmentPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass