; LLVM IR from Shah-Shishir/Codeforces-Solutions :: 977A. Wrong Subtraction (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"

@.str = external hidden unnamed_addr constant [6 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [4 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 i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #3
  br label %6

6:                                                ; preds = %30, %0
  %7 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef %2, ptr noundef %3)
  %8 = icmp ne i32 %7, -1
  br i1 %8, label %9, label %33

9:                                                ; preds = %6
  br label %10

10:                                               ; preds = %29, %9
  %11 = load i32, ptr %3, align 4, !tbaa !5
  %12 = add nsw i32 %11, -1
  store i32 %12, ptr %3, align 4, !tbaa !5
  %13 = icmp ne i32 %11, 0
  br i1 %13, label %14, label %30

14:                                               ; preds = %10
  %15 = load i32, ptr %2, align 4, !tbaa !5
  %16 = icmp eq i32 %15, 0
  br i1 %16, label %17, label %18

17:                                               ; preds = %14
  br label %30

18:                                               ; preds = %14
  %19 = load i32, ptr %2, align 4, !tbaa !5
  %20 = srem i32 %19, 10
  store i32 %20, ptr %4, align 4, !tbaa !5
  %21 = load i32, ptr %4, align 4, !tbaa !5
  %22 = icmp eq i32 %21, 0
  br i1 %22, label %23, label %26

23:                                               ; preds = %18
  %24 = load i32, ptr %2, align 4, !tbaa !5
  %25 = sdiv i32 %24, 10
  store i32 %25, ptr %2, align 4, !tbaa !5
  br label %29

26:                                               ; preds = %18
  %27 = load i32, ptr %2, align 4, !tbaa !5
  %28 = add nsw i32 %27, -1
  store i32 %28, ptr %2, align 4, !tbaa !5
  br label %29

29:                                               ; preds = %26, %23
  br label %10, !llvm.loop !9

30:                                               ; preds = %17, %10
  %31 = load i32, ptr %2, align 4, !tbaa !5
  %32 = call i32 (ptr, ...) @printf(ptr noundef @.str.1, i32 noundef %31)
  br label %6, !llvm.loop !11

33:                                               ; preds = %6
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #3
  ret i32 0
}

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

declare i32 @__isoc99_scanf(ptr noundef, ...) #2

declare i32 @printf(ptr noundef, ...) #2

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

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 = { 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 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}


; 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"

@.str = external hidden unnamed_addr constant [6 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [4 x i8], align 1

; Function Attrs: mustprogress nofree norecurse nounwind uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #3
  %3 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull %1, ptr noundef nonnull %2)
  %.not8 = icmp eq i32 %3, -1
  br i1 %.not8, label %._crit_edge9, label %.preheader

.preheader:                                       ; preds = %0, %15
  %.promoted = load i32, ptr %2, align 4, !tbaa !5
  %.promoted3 = load i32, ptr %1, align 4
  %4 = add nsw i32 %.promoted, -1
  %5 = icmp eq i32 %.promoted, 0
  %6 = icmp eq i32 %.promoted3, 0
  %or.cond5 = select i1 %5, i1 true, i1 %6
  br i1 %or.cond5, label %15, label %.lr.ph

.lr.ph:                                           ; preds = %.preheader, %.lr.ph
  %7 = phi i32 [ %12, %.lr.ph ], [ %4, %.preheader ]
  %storemerge46 = phi i32 [ %storemerge, %.lr.ph ], [ %.promoted3, %.preheader ]
  %8 = srem i32 %storemerge46, 10
  %9 = sdiv i32 %storemerge46, 10
  %10 = icmp eq i32 %8, 0
  %11 = add nsw i32 %storemerge46, -1
  %storemerge = select i1 %10, i32 %9, i32 %11
  %12 = add nsw i32 %7, -1
  %13 = icmp eq i32 %7, 0
  %14 = icmp eq i32 %storemerge, 0
  %or.cond = select i1 %13, i1 true, i1 %14
  br i1 %or.cond, label %._crit_edge, label %.lr.ph, !llvm.loop !9

._crit_edge:                                      ; preds = %.lr.ph
  store i32 %storemerge, ptr %1, align 4, !tbaa !5
  br label %15

15:                                               ; preds = %._crit_edge, %.preheader
  %.lcssa2 = phi i32 [ %12, %._crit_edge ], [ %4, %.preheader ]
  %.lcssa = phi i32 [ %storemerge, %._crit_edge ], [ %.promoted3, %.preheader ]
  store i32 %.lcssa2, ptr %2, align 4, !tbaa !5
  %16 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1, i32 noundef %.lcssa)
  %17 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull %1, ptr noundef nonnull %2)
  %.not = icmp eq i32 %17, -1
  br i1 %.not, label %._crit_edge9, label %.preheader, !llvm.loop !11

._crit_edge9:                                     ; preds = %15, %0
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #3
  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: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

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

attributes #0 = { mustprogress nofree norecurse 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 #1 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { nofree nounwind "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 = { 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 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}


; Effective O3 passes: DivRemPairsPass,EarlyCSEPass,GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LICMPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass