; LLVM IR from plskz/competitive-programming :: Junior Training Sheet/A (205)

; 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" }
%"struct.std::pair" = type { i32, i32 }

@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [13 x i8], align 1

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca ptr, align 8
  %4 = alloca i64, align 8
  %5 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  %6 = call noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext false)
  %7 = load ptr, ptr @_ZSt3cin, align 8, !tbaa !5
  %8 = getelementptr i8, ptr %7, i64 -24
  %9 = load i64, ptr %8, align 8
  %10 = getelementptr inbounds i8, ptr @_ZSt3cin, i64 %9
  %11 = call noundef ptr @_ZNSt9basic_iosIcSt11char_traitsIcEE3tieEPSo(ptr noundef nonnull align 8 dereferenceable(264) %10, ptr noundef null)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #6
  %12 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %2)
  %13 = load i32, ptr %2, align 4, !tbaa !8
  %14 = zext i32 %13 to i64
  %15 = call ptr @llvm.stacksave.p0()
  store ptr %15, ptr %3, align 8
  %16 = alloca %"struct.std::pair", i64 %14, align 16
  store i64 %14, ptr %4, align 8
  %17 = icmp eq i64 %14, 0
  br i1 %17, label %24, label %18

18:                                               ; preds = %0
  %19 = getelementptr inbounds %"struct.std::pair", ptr %16, i64 %14
  br label %20

20:                                               ; preds = %20, %18
  %21 = phi ptr [ %16, %18 ], [ %22, %20 ]
  call void @_ZNSt4pairIiiEC2IiiTnNSt9enable_ifIXsr6__and_ISt37__is_implicitly_default_constructibleIT_ES3_IT0_EEE5valueEbE4typeELb1EEEv(ptr noundef nonnull align 4 dereferenceable(8) %21)
  %22 = getelementptr inbounds %"struct.std::pair", ptr %21, i64 1
  %23 = icmp eq ptr %22, %19
  br i1 %23, label %24, label %20

24:                                               ; preds = %20, %0
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #6
  store i32 0, ptr %5, align 4, !tbaa !8
  br label %25

25:                                               ; preds = %42, %24
  %26 = load i32, ptr %5, align 4, !tbaa !8
  %27 = load i32, ptr %2, align 4, !tbaa !8
  %28 = icmp slt i32 %26, %27
  br i1 %28, label %30, label %29

29:                                               ; preds = %25
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #6
  br label %45

30:                                               ; preds = %25
  %31 = load i32, ptr %5, align 4, !tbaa !8
  %32 = sext i32 %31 to i64
  %33 = getelementptr inbounds %"struct.std::pair", ptr %16, i64 %32
  %34 = getelementptr inbounds %"struct.std::pair", ptr %33, i32 0, i32 0
  %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) %34)
  %36 = load i32, ptr %5, align 4, !tbaa !8
  %37 = add nsw i32 %36, 1
  %38 = load i32, ptr %5, align 4, !tbaa !8
  %39 = sext i32 %38 to i64
  %40 = getelementptr inbounds %"struct.std::pair", ptr %16, i64 %39
  %41 = getelementptr inbounds %"struct.std::pair", ptr %40, i32 0, i32 1
  store i32 %37, ptr %41, align 4, !tbaa !11
  br label %42

42:                                               ; preds = %30
  %43 = load i32, ptr %5, align 4, !tbaa !8
  %44 = add nsw i32 %43, 1
  store i32 %44, ptr %5, align 4, !tbaa !8
  br label %25, !llvm.loop !13

45:                                               ; preds = %29
  %46 = load i32, ptr %2, align 4, !tbaa !8
  %47 = sext i32 %46 to i64
  %48 = getelementptr inbounds %"struct.std::pair", ptr %16, i64 %47
  call void @_ZSt4sortIPSt4pairIiiEEvT_S3_(ptr noundef %16, ptr noundef %48)
  %49 = getelementptr inbounds %"struct.std::pair", ptr %16, i64 0
  %50 = getelementptr inbounds %"struct.std::pair", ptr %49, i32 0, i32 0
  %51 = load i32, ptr %50, align 16, !tbaa !15
  %52 = getelementptr inbounds %"struct.std::pair", ptr %16, i64 1
  %53 = getelementptr inbounds %"struct.std::pair", ptr %52, i32 0, i32 0
  %54 = load i32, ptr %53, align 8, !tbaa !15
  %55 = icmp eq i32 %51, %54
  br i1 %55, label %56, label %58

56:                                               ; preds = %45
  %57 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef @.str)
  br label %63

58:                                               ; preds = %45
  %59 = getelementptr inbounds %"struct.std::pair", ptr %16, i64 0
  %60 = getelementptr inbounds %"struct.std::pair", ptr %59, i32 0, i32 1
  %61 = load i32, ptr %60, align 4, !tbaa !11
  %62 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %61)
  br label %63

63:                                               ; preds = %58, %56
  store i32 0, ptr %1, align 4
  %64 = load ptr, ptr %3, align 8
  call void @llvm.stackrestore.p0(ptr %64)
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #6
  %65 = load i32, ptr %1, align 4
  ret i32 %65
}

declare noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext) #1

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

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #3

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn
declare ptr @llvm.stacksave.p0() #4

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZNSt4pairIiiEC2IiiTnNSt9enable_ifIXsr6__and_ISt37__is_implicitly_default_constructibleIT_ES3_IT0_EEE5valueEbE4typeELb1EEEv(ptr noundef nonnull align 4 dereferenceable(8)) unnamed_addr #2 align 2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #3

; Function Attrs: inlinehint mustprogress uwtable
declare dso_local void @_ZSt4sortIPSt4pairIiiEEvT_S3_(ptr noundef, ptr noundef) #5

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #5

declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn
declare void @llvm.stackrestore.p0(ptr) #4

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 = { "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 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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #4 = { nocallback nofree nosync nounwind willreturn }
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 = !{!12, !9, i64 4}
!12 = !{!"_ZTSSt4pairIiiE", !9, i64 0, !9, i64 4}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}
!15 = !{!12, !9, i64 0}


; 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" }
%"struct.std::pair" = type { i32, i32 }

@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [13 x i8], align 1

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = alloca i32, align 4
  %2 = tail call noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext false)
  %3 = load ptr, ptr @_ZSt3cin, align 8, !tbaa !5
  %4 = getelementptr i8, ptr %3, i64 -24
  %5 = load i64, ptr %4, align 8
  %6 = getelementptr inbounds i8, ptr @_ZSt3cin, i64 %5
  %7 = tail call noundef ptr @_ZNSt9basic_iosIcSt11char_traitsIcEE3tieEPSo(ptr noundef nonnull align 8 dereferenceable(264) %6, ptr noundef null)
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #6
  %8 = 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)
  %9 = load i32, ptr %1, align 4, !tbaa !8
  %10 = zext i32 %9 to i64
  %11 = call ptr @llvm.stacksave.p0()
  %12 = alloca %"struct.std::pair", i64 %10, align 16
  %13 = icmp eq i32 %9, 0
  br i1 %13, label %.loopexit, label %14

14:                                               ; preds = %0
  %15 = getelementptr inbounds %"struct.std::pair", ptr %12, i64 %10
  br label %16

16:                                               ; preds = %16, %14
  %17 = phi ptr [ %12, %14 ], [ %18, %16 ]
  call void @_ZNSt4pairIiiEC2IiiTnNSt9enable_ifIXsr6__and_ISt37__is_implicitly_default_constructibleIT_ES3_IT0_EEE5valueEbE4typeELb1EEEv(ptr noundef nonnull align 4 dereferenceable(8) %17)
  %18 = getelementptr inbounds i8, ptr %17, i64 8
  %19 = icmp eq ptr %18, %15
  br i1 %19, label %.loopexit, label %16

.loopexit:                                        ; preds = %16, %0
  %20 = load i32, ptr %1, align 4, !tbaa !8
  %21 = icmp sgt i32 %20, 0
  br i1 %21, label %.lr.ph, label %.loopexit.._crit_edge_crit_edge

.loopexit.._crit_edge_crit_edge:                  ; preds = %.loopexit
  %.pre = sext i32 %20 to i64
  br label %._crit_edge

._crit_edge:                                      ; preds = %.lr.ph, %.loopexit.._crit_edge_crit_edge
  %.pre-phi = phi i64 [ %.pre, %.loopexit.._crit_edge_crit_edge ], [ %32, %.lr.ph ]
  %22 = getelementptr inbounds %"struct.std::pair", ptr %12, i64 %.pre-phi
  call void @_ZSt4sortIPSt4pairIiiEEvT_S3_(ptr noundef nonnull %12, ptr noundef nonnull %22)
  %23 = load i32, ptr %12, align 16, !tbaa !11
  %24 = getelementptr inbounds i8, ptr %12, i64 8
  %25 = load i32, ptr %24, align 8, !tbaa !11
  %26 = icmp eq i32 %23, %25
  br i1 %26, label %34, label %36

.lr.ph:                                           ; preds = %.loopexit, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %.loopexit ]
  %27 = getelementptr inbounds %"struct.std::pair", ptr %12, i64 %indvars.iv
  %28 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %27)
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %29 = getelementptr inbounds i8, ptr %27, i64 4
  %30 = trunc nuw nsw i64 %indvars.iv.next to i32
  store i32 %30, ptr %29, align 4, !tbaa !13
  %31 = load i32, ptr %1, align 4, !tbaa !8
  %32 = sext i32 %31 to i64
  %33 = icmp slt i64 %indvars.iv.next, %32
  br i1 %33, label %.lr.ph, label %._crit_edge, !llvm.loop !14

34:                                               ; preds = %._crit_edge
  %35 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef nonnull @.str)
  br label %40

36:                                               ; preds = %._crit_edge
  %37 = getelementptr inbounds i8, ptr %12, i64 4
  %38 = load i32, ptr %37, align 4, !tbaa !13
  %39 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %38)
  br label %40

40:                                               ; preds = %36, %34
  call void @llvm.stackrestore.p0(ptr %11)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #6
  ret i32 0
}

declare noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext) local_unnamed_addr #1

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

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #3

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 #1

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn
declare ptr @llvm.stacksave.p0() #4

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZNSt4pairIiiEC2IiiTnNSt9enable_ifIXsr6__and_ISt37__is_implicitly_default_constructibleIT_ES3_IT0_EEE5valueEbE4typeELb1EEEv(ptr noundef nonnull align 4 dereferenceable(8)) unnamed_addr #2 align 2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #3

; Function Attrs: inlinehint mustprogress uwtable
declare dso_local void @_ZSt4sortIPSt4pairIiiEEvT_S3_(ptr noundef, ptr noundef) local_unnamed_addr #5

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #5

declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) local_unnamed_addr #1

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn
declare void @llvm.stackrestore.p0(ptr) #4

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 = { "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 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 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #4 = { mustprogress nocallback nofree nosync nounwind willreturn }
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 = !{!12, !9, i64 0}
!12 = !{!"_ZTSSt4pairIiiE", !9, i64 0, !9, i64 4}
!13 = !{!12, !9, i64 4}
!14 = distinct !{!14, !15}
!15 = !{!"llvm.loop.mustprogress"}


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