; LLVM IR from tangjz/acm-icpc :: 51nod (1008)

; 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
@p = external dso_local global i32, align 4
@ans = external dso_local global i32, align 4
@.str = external hidden unnamed_addr constant [5 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
  store i32 0, ptr %1, align 4
  %3 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef @n, ptr noundef @p)
  store i32 1, ptr @ans, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #3
  store i32 2, ptr %2, align 4, !tbaa !5
  br label %4

4:                                                ; preds = %19, %0
  %5 = load i32, ptr %2, align 4, !tbaa !5
  %6 = load i32, ptr @n, align 4, !tbaa !5
  %7 = icmp sle i32 %5, %6
  br i1 %7, label %9, label %8

8:                                                ; preds = %4
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #3
  br label %22

9:                                                ; preds = %4
  %10 = load i32, ptr @ans, align 4, !tbaa !5
  %11 = sext i32 %10 to i64
  %12 = load i32, ptr %2, align 4, !tbaa !5
  %13 = sext i32 %12 to i64
  %14 = mul nsw i64 %11, %13
  %15 = load i32, ptr @p, align 4, !tbaa !5
  %16 = sext i32 %15 to i64
  %17 = srem i64 %14, %16
  %18 = trunc i64 %17 to i32
  store i32 %18, ptr @ans, align 4, !tbaa !5
  br label %19

19:                                               ; preds = %9
  %20 = load i32, ptr %2, align 4, !tbaa !5
  %21 = add nsw i32 %20, 1
  store i32 %21, ptr %2, align 4, !tbaa !5
  br label %4, !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)
  ret i32 0
}

declare i32 @__isoc99_scanf(ptr noundef, ...) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #2

declare i32 @printf(ptr noundef, ...) #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 = { "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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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"}


; 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
@p = external dso_local global i32, align 4
@ans = external dso_local local_unnamed_addr global i32, align 4
@.str = external hidden unnamed_addr constant [5 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 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull @n, ptr noundef nonnull @p)
  store i32 1, ptr @ans, align 4, !tbaa !5
  %2 = load i32, ptr @n, align 4, !tbaa !5
  %.not3 = icmp slt i32 %2, 2
  br i1 %.not3, label %14, label %.lr.ph

.lr.ph:                                           ; preds = %0
  %3 = load i32, ptr @p, align 4, !tbaa !5
  %4 = sext i32 %3 to i64
  %5 = add nuw i32 %2, 1
  %wide.trip.count = zext i32 %5 to i64
  %xtraiter = and i64 %wide.trip.count, 1
  %6 = icmp eq i32 %5, 3
  br i1 %6, label %._crit_edge.unr-lcssa, label %.lr.ph.new

.lr.ph.new:                                       ; preds = %.lr.ph
  %7 = and i64 %wide.trip.count, 4294967294
  %8 = add nsw i64 %7, -4
  br label %17

._crit_edge.unr-lcssa.loopexit:                   ; preds = %17
  %9 = shl i64 %24, 32
  %10 = ashr exact i64 %9, 32
  br label %._crit_edge.unr-lcssa

._crit_edge.unr-lcssa:                            ; preds = %._crit_edge.unr-lcssa.loopexit, %.lr.ph
  %.lcssa.ph = phi i64 [ poison, %.lr.ph ], [ %24, %._crit_edge.unr-lcssa.loopexit ]
  %indvars.iv.unr = phi i64 [ 2, %.lr.ph ], [ %indvars.iv.next.1, %._crit_edge.unr-lcssa.loopexit ]
  %.unr = phi i64 [ 1, %.lr.ph ], [ %10, %._crit_edge.unr-lcssa.loopexit ]
  %lcmp.mod.not = icmp eq i64 %xtraiter, 0
  br i1 %lcmp.mod.not, label %._crit_edge, label %._crit_edge.epilog-lcssa

._crit_edge.epilog-lcssa:                         ; preds = %._crit_edge.unr-lcssa
  %11 = mul nsw i64 %.unr, %indvars.iv.unr
  %12 = srem i64 %11, %4
  br label %._crit_edge

._crit_edge:                                      ; preds = %._crit_edge.unr-lcssa, %._crit_edge.epilog-lcssa
  %.lcssa = phi i64 [ %.lcssa.ph, %._crit_edge.unr-lcssa ], [ %12, %._crit_edge.epilog-lcssa ]
  %13 = trunc nsw i64 %.lcssa to i32
  store i32 %13, ptr @ans, align 4, !tbaa !5
  br label %14

14:                                               ; preds = %._crit_edge, %0
  %15 = phi i32 [ %13, %._crit_edge ], [ 1, %0 ]
  %16 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1, i32 noundef %15)
  ret i32 0

17:                                               ; preds = %17, %.lr.ph.new
  %indvars.iv = phi i64 [ 2, %.lr.ph.new ], [ %indvars.iv.next.1, %17 ]
  %18 = phi i64 [ 1, %.lr.ph.new ], [ %24, %17 ]
  %niter = phi i64 [ 0, %.lr.ph.new ], [ %niter.next.1, %17 ]
  %sext = shl i64 %18, 32
  %19 = ashr exact i64 %sext, 32
  %20 = mul nsw i64 %19, %indvars.iv
  %21 = srem i64 %20, %4
  %indvars.iv.next = or disjoint i64 %indvars.iv, 1
  %sext.1 = shl i64 %21, 32
  %22 = ashr exact i64 %sext.1, 32
  %23 = mul nsw i64 %22, %indvars.iv.next
  %24 = srem i64 %23, %4
  %indvars.iv.next.1 = add nuw nsw i64 %indvars.iv, 2
  %niter.next.1 = add i64 %niter, 2
  %niter.ncmp.1 = icmp eq i64 %niter, %8
  br i1 %niter.ncmp.1, label %._crit_edge.unr-lcssa.loopexit, label %17, !llvm.loop !9
}

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #1

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

!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"}


; Effective O3 passes: GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LICMPass,LoopRotatePass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass