; LLVM IR from kazunetakahashi/atcoder :: 2019/0525_ABC127/past (F2)

; 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 }

@Q = external dso_local global i32, align 4
@a = external dso_local global i64, align 8
@b = external dso_local global i64, align 8
@_ZSt3cin = external global %"class.std::basic_istream", align 8

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z5mergev() #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 uwtable
declare dso_local void @_Z5flushv() #0

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #2 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i8, align 1
  store i32 0, ptr %1, align 4
  %4 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) @Q)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #4
  store i32 0, ptr %2, align 4, !tbaa !5
  br label %5

5:                                                ; preds = %20, %0
  %6 = load i32, ptr %2, align 4, !tbaa !5
  %7 = load i32, ptr @Q, align 4, !tbaa !5
  %8 = icmp slt i32 %6, %7
  br i1 %8, label %10, label %9

9:                                                ; preds = %5
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #4
  br label %23

10:                                               ; preds = %5
  call void @llvm.lifetime.start.p0(i64 1, ptr %3) #4
  %11 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcEERSt13basic_istreamIT_T0_ES6_RS3_(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 1 dereferenceable(1) %3)
  %12 = load i8, ptr %3, align 1, !tbaa !9
  %13 = sext i8 %12 to i32
  %14 = icmp eq i32 %13, 49
  br i1 %14, label %15, label %18

15:                                               ; preds = %10
  %16 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(8) @a)
  %17 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16) %16, ptr noundef nonnull align 8 dereferenceable(8) @b)
  call void @_Z5mergev()
  br label %19

18:                                               ; preds = %10
  call void @_Z5flushv()
  br label %19

19:                                               ; preds = %18, %15
  call void @llvm.lifetime.end.p0(i64 1, ptr %3) #4
  br label %20

20:                                               ; preds = %19
  %21 = load i32, ptr %2, align 4, !tbaa !5
  %22 = add nsw i32 %21, 1
  store i32 %22, ptr %2, align 4, !tbaa !5
  br label %5, !llvm.loop !10

23:                                               ; preds = %9
  %24 = load i32, ptr %1, align 4
  ret i32 %24
}

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) #3

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcEERSt13basic_istreamIT_T0_ES6_RS3_(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 1 dereferenceable(1)) #3

; 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)) #0 align 2

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 = { 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 = !{!7, !7, i64 0}
!10 = distinct !{!10, !11}
!11 = !{!"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::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 }

@Q = external dso_local global i32, align 4
@a = external dso_local global i64, align 8
@b = external dso_local global i64, align 8
@_ZSt3cin = external global %"class.std::basic_istream", align 8

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z5mergev() local_unnamed_addr #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

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z5flushv() local_unnamed_addr #0

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #2 {
  %1 = alloca i8, align 1
  %2 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) @Q)
  %3 = load i32, ptr @Q, align 4, !tbaa !5
  %4 = icmp sgt i32 %3, 0
  br i1 %4, label %.lr.ph, label %._crit_edge

._crit_edge:                                      ; preds = %12, %0
  ret i32 0

.lr.ph:                                           ; preds = %0, %12
  %.03 = phi i32 [ %13, %12 ], [ 0, %0 ]
  call void @llvm.lifetime.start.p0(i64 1, ptr nonnull %1) #4
  %5 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcEERSt13basic_istreamIT_T0_ES6_RS3_(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 1 dereferenceable(1) %1)
  %6 = load i8, ptr %1, align 1, !tbaa !9
  %7 = icmp eq i8 %6, 49
  br i1 %7, label %8, label %11

8:                                                ; preds = %.lr.ph
  %9 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 8 dereferenceable(8) @a)
  %10 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERx(ptr noundef nonnull align 8 dereferenceable(16) %9, ptr noundef nonnull align 8 dereferenceable(8) @b)
  call void @_Z5mergev()
  br label %12

11:                                               ; preds = %.lr.ph
  call void @_Z5flushv()
  br label %12

12:                                               ; preds = %11, %8
  call void @llvm.lifetime.end.p0(i64 1, ptr nonnull %1) #4
  %13 = add nuw nsw i32 %.03, 1
  %14 = load i32, ptr @Q, align 4, !tbaa !5
  %15 = icmp slt i32 %13, %14
  br i1 %15, label %.lr.ph, label %._crit_edge, !llvm.loop !10
}

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 #3

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZStrsIcSt11char_traitsIcEERSt13basic_istreamIT_T0_ES6_RS3_(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 1 dereferenceable(1)) local_unnamed_addr #3

; 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 #0 align 2

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 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 = { 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 = !{!7, !7, i64 0}
!10 = distinct !{!10, !11}
!11 = !{!"llvm.loop.mustprogress"}


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