; LLVM IR from tangjz/acm-icpc :: poj (3048)

; 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"

@n = external dso_local global i32, align 4
@ans = external dso_local global i32, align 4
@fact = external dso_local global i32, align 4
@.str = external hidden unnamed_addr constant [3 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [4 x i8], align 1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef i32 @_Z7maxfacti(i32 noundef) #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 norecurse uwtable
define dso_local noundef i32 @main() #2 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  br label %4

4:                                                ; preds = %22, %0
  %5 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef @n)
  %6 = icmp ne i32 %5, -1
  br i1 %6, label %7, label %25

7:                                                ; preds = %4
  store i32 0, ptr @fact, align 4, !tbaa !5
  store i32 0, ptr @ans, align 4, !tbaa !5
  br label %8

8:                                                ; preds = %21, %7
  %9 = load i32, ptr @n, align 4, !tbaa !5
  %10 = add nsw i32 %9, -1
  store i32 %10, ptr @n, align 4, !tbaa !5
  %11 = icmp ne i32 %9, 0
  br i1 %11, label %12, label %22

12:                                               ; preds = %8
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #4
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #4
  %13 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef %2)
  %14 = load i32, ptr %2, align 4, !tbaa !5
  %15 = call noundef i32 @_Z7maxfacti(i32 noundef %14)
  store i32 %15, ptr %3, align 4, !tbaa !5
  %16 = load i32, ptr @fact, align 4, !tbaa !5
  %17 = icmp sgt i32 %15, %16
  br i1 %17, label %18, label %21

18:                                               ; preds = %12
  %19 = load i32, ptr %2, align 4, !tbaa !5
  store i32 %19, ptr @ans, align 4, !tbaa !5
  %20 = load i32, ptr %3, align 4, !tbaa !5
  store i32 %20, ptr @fact, align 4, !tbaa !5
  br label %21

21:                                               ; preds = %18, %12
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #4
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #4
  br label %8, !llvm.loop !9

22:                                               ; preds = %8
  %23 = load i32, ptr @ans, align 4, !tbaa !5
  %24 = call i32 (ptr, ...) @printf(ptr noundef @.str.1, i32 noundef %23)
  br label %4, !llvm.loop !11

25:                                               ; preds = %4
  ret i32 0
}

declare i32 @__isoc99_scanf(ptr noundef, ...) #3

declare i32 @printf(ptr noundef, ...) #3

attributes #0 = { 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 #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 = 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"

@n = external dso_local global i32, align 4
@ans = external dso_local local_unnamed_addr global i32, align 4
@fact = external dso_local local_unnamed_addr global i32, align 4
@.str = external hidden unnamed_addr constant [3 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [4 x i8], align 1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef i32 @_Z7maxfacti(i32 noundef) 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 norecurse nounwind uwtable
define dso_local noundef i32 @main() local_unnamed_addr #2 {
  %1 = alloca i32, align 4
  %2 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull @n)
  %.not3 = icmp eq i32 %2, -1
  br i1 %.not3, label %._crit_edge6, label %.lr.ph5

.lr.ph5:                                          ; preds = %0, %._crit_edge
  store i32 0, ptr @fact, align 4, !tbaa !5
  store i32 0, ptr @ans, align 4, !tbaa !5
  %3 = load i32, ptr @n, align 4, !tbaa !5
  %4 = add nsw i32 %3, -1
  store i32 %4, ptr @n, align 4, !tbaa !5
  %.not12 = icmp eq i32 %3, 0
  br i1 %.not12, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph5, %12
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #4
  %5 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull %1)
  %6 = load i32, ptr %1, align 4, !tbaa !5
  %7 = call noundef i32 @_Z7maxfacti(i32 noundef %6)
  %8 = load i32, ptr @fact, align 4, !tbaa !5
  %9 = icmp sgt i32 %7, %8
  br i1 %9, label %10, label %12

10:                                               ; preds = %.lr.ph
  %11 = load i32, ptr %1, align 4, !tbaa !5
  store i32 %11, ptr @ans, align 4, !tbaa !5
  store i32 %7, ptr @fact, align 4, !tbaa !5
  br label %12

12:                                               ; preds = %10, %.lr.ph
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #4
  %13 = load i32, ptr @n, align 4, !tbaa !5
  %14 = add nsw i32 %13, -1
  store i32 %14, ptr @n, align 4, !tbaa !5
  %.not1 = icmp eq i32 %13, 0
  br i1 %.not1, label %._crit_edge.loopexit, label %.lr.ph, !llvm.loop !9

._crit_edge.loopexit:                             ; preds = %12
  %.pre = load i32, ptr @ans, align 4, !tbaa !5
  br label %._crit_edge

._crit_edge:                                      ; preds = %._crit_edge.loopexit, %.lr.ph5
  %15 = phi i32 [ %.pre, %._crit_edge.loopexit ], [ 0, %.lr.ph5 ]
  %16 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1, i32 noundef %15)
  %17 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull @n)
  %.not = icmp eq i32 %17, -1
  br i1 %.not, label %._crit_edge6, label %.lr.ph5, !llvm.loop !11

._crit_edge6:                                     ; preds = %._crit_edge, %0
  ret i32 0
}

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #3

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #3

attributes #0 = { 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 #1 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { mustprogress 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 #3 = { 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 #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 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}


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