; LLVM IR from Izaron/ACM-ICPC :: Timus Online Judge/Volume 12/2102. Michael and Cryptography (main)

; 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" }

@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [4 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [3 x i8], align 1

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i64, align 8
  %3 = alloca i32, align 4
  %4 = alloca i64, align 8
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.start.p0(i64 8, ptr %2) #4
  %5 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(8) %2)
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #4
  store i32 0, ptr %3, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  store i64 2, ptr %4, align 8, !tbaa !9
  br label %6

6:                                                ; preds = %24, %0
  %7 = load i64, ptr %4, align 8, !tbaa !9
  %8 = sitofp i64 %7 to double
  %9 = fcmp ole double %8, 2.000000e+07
  br i1 %9, label %11, label %10

10:                                               ; preds = %6
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  br label %27

11:                                               ; preds = %6
  br label %12

12:                                               ; preds = %17, %11
  %13 = load i64, ptr %2, align 8, !tbaa !9
  %14 = load i64, ptr %4, align 8, !tbaa !9
  %15 = srem i64 %13, %14
  %16 = icmp eq i64 %15, 0
  br i1 %16, label %17, label %23

17:                                               ; preds = %12
  %18 = load i32, ptr %3, align 4, !tbaa !5
  %19 = add nsw i32 %18, 1
  store i32 %19, ptr %3, align 4, !tbaa !5
  %20 = load i64, ptr %4, align 8, !tbaa !9
  %21 = load i64, ptr %2, align 8, !tbaa !9
  %22 = sdiv i64 %21, %20
  store i64 %22, ptr %2, align 8, !tbaa !9
  br label %12, !llvm.loop !11

23:                                               ; preds = %12
  br label %24

24:                                               ; preds = %23
  %25 = load i64, ptr %4, align 8, !tbaa !9
  %26 = add nsw i64 %25, 1
  store i64 %26, ptr %4, align 8, !tbaa !9
  br label %6, !llvm.loop !13

27:                                               ; preds = %10
  %28 = load i64, ptr %2, align 8, !tbaa !9
  %29 = icmp ne i64 %28, 1
  br i1 %29, label %30, label %33

30:                                               ; preds = %27
  %31 = load i32, ptr %3, align 4, !tbaa !5
  %32 = add nsw i32 %31, 1
  store i32 %32, ptr %3, align 4, !tbaa !5
  br label %33

33:                                               ; preds = %30, %27
  %34 = load i32, ptr %3, align 4, !tbaa !5
  %35 = icmp eq i32 %34, 20
  br i1 %35, label %36, label %38

36:                                               ; preds = %33
  %37 = 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 %40

38:                                               ; preds = %33
  %39 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef @.str.1)
  br label %40

40:                                               ; preds = %38, %36
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %2) #4
  %41 = load i32, ptr %1, align 4
  ret i32 %41
}

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

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 8 dereferenceable(8)) #2 align 2

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

; 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) #3

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 = { 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 = { 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 #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, !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 = 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::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" }

@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [4 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [3 x i8], align 1

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = alloca i64, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %1) #4
  %2 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(8) %1)
  %.promoted10 = load i64, ptr %1, align 8, !tbaa !5
  br label %.preheader

.preheader:                                       ; preds = %0, %14
  %.015 = phi i64 [ 2, %0 ], [ %16, %14 ]
  %.0814 = phi i32 [ 0, %0 ], [ %.1.lcssa, %14 ]
  %.lcssa1213 = phi i64 [ %.promoted10, %0 ], [ %15, %14 ]
  %3 = srem i64 %.lcssa1213, %.015
  %4 = icmp eq i64 %3, 0
  br i1 %4, label %.lr.ph, label %14

5:                                                ; preds = %14
  %.not = icmp ne i64 %15, 1
  %6 = zext i1 %.not to i32
  %spec.select = add nsw i32 %.1.lcssa, %6
  %7 = icmp eq i32 %spec.select, 20
  %.str..str.1 = select i1 %7, ptr @.str, ptr @.str.1
  %8 = 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..str.1)
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %1) #4
  ret i32 0

.lr.ph:                                           ; preds = %.preheader, %.lr.ph
  %.19 = phi i32 [ %10, %.lr.ph ], [ %.0814, %.preheader ]
  %9 = phi i64 [ %11, %.lr.ph ], [ %.lcssa1213, %.preheader ]
  %10 = add nsw i32 %.19, 1
  %11 = sdiv i64 %9, %.015
  %12 = srem i64 %11, %.015
  %13 = icmp eq i64 %12, 0
  br i1 %13, label %.lr.ph, label %._crit_edge, !llvm.loop !9

._crit_edge:                                      ; preds = %.lr.ph
  store i64 %11, ptr %1, align 8, !tbaa !5
  br label %14

14:                                               ; preds = %._crit_edge, %.preheader
  %15 = phi i64 [ %11, %._crit_edge ], [ %.lcssa1213, %.preheader ]
  %.1.lcssa = phi i32 [ %10, %._crit_edge ], [ %.0814, %.preheader ]
  %16 = add nuw nsw i64 %.015, 1
  %exitcond.not = icmp eq i64 %16, 20000001
  br i1 %exitcond.not, label %5, label %.preheader, !llvm.loop !11
}

; 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 uwtable
declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 8 dereferenceable(8)) local_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) #1

; 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 #3

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 = { 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 = { 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 #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, !6, i64 0}
!6 = !{!"long long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LICMPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,ReassociatePass,SROAPass,SimplifyCFGPass