; LLVM IR from tangjz/acm-icpc :: 51nod (1605)

; 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"

@t = external dso_local global i32, align 4
@n = external dso_local global i32, align 4
@m = external dso_local global i32, align 4
@x = external dso_local global i32, align 4
@ans = 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 [5 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [7 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [6 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
  store i32 0, ptr %1, align 4
  %5 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef @t)
  br label %6

6:                                                ; preds = %35, %0
  %7 = load i32, ptr @t, align 4, !tbaa !5
  %8 = add nsw i32 %7, -1
  store i32 %8, ptr @t, align 4, !tbaa !5
  %9 = icmp ne i32 %7, 0
  br i1 %9, label %10, label %41

10:                                               ; preds = %6
  store i32 0, ptr @ans, align 4, !tbaa !5
  %11 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.1, ptr noundef @n, ptr noundef @m)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #3
  store i32 0, ptr %2, align 4, !tbaa !5
  br label %12

12:                                               ; preds = %32, %10
  %13 = load i32, ptr %2, align 4, !tbaa !5
  %14 = load i32, ptr @n, align 4, !tbaa !5
  %15 = icmp slt i32 %13, %14
  br i1 %15, label %17, label %16

16:                                               ; preds = %12
  store i32 4, ptr %3, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #3
  br label %35

17:                                               ; preds = %12
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  store i32 0, ptr %4, align 4, !tbaa !5
  br label %18

18:                                               ; preds = %28, %17
  %19 = load i32, ptr %4, align 4, !tbaa !5
  %20 = load i32, ptr @m, align 4, !tbaa !5
  %21 = icmp slt i32 %19, %20
  br i1 %21, label %23, label %22

22:                                               ; preds = %18
  store i32 7, ptr %3, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  br label %31

23:                                               ; preds = %18
  %24 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef @x)
  %25 = load i32, ptr @x, align 4, !tbaa !5
  %26 = load i32, ptr @ans, align 4, !tbaa !5
  %27 = xor i32 %26, %25
  store i32 %27, ptr @ans, align 4, !tbaa !5
  br label %28

28:                                               ; preds = %23
  %29 = load i32, ptr %4, align 4, !tbaa !5
  %30 = add nsw i32 %29, 1
  store i32 %30, ptr %4, align 4, !tbaa !5
  br label %18, !llvm.loop !9

31:                                               ; preds = %22
  br label %32

32:                                               ; preds = %31
  %33 = load i32, ptr %2, align 4, !tbaa !5
  %34 = add nsw i32 %33, 1
  store i32 %34, ptr %2, align 4, !tbaa !5
  br label %12, !llvm.loop !11

35:                                               ; preds = %16
  %36 = load i32, ptr @ans, align 4, !tbaa !5
  %37 = icmp ne i32 %36, 0
  %38 = zext i1 %37 to i64
  %39 = select i1 %37, ptr @.str.2, ptr @.str.3
  %40 = call i32 @puts(ptr noundef %39)
  br label %6, !llvm.loop !12

41:                                               ; preds = %6
  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 @puts(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"}
!11 = distinct !{!11, !10}
!12 = distinct !{!12, !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"

@t = external dso_local global i32, align 4
@n = external dso_local global i32, align 4
@m = external dso_local global i32, align 4
@x = external dso_local global i32, align 4
@ans = 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 [5 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [7 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [6 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 @t)
  %2 = load i32, ptr @t, align 4, !tbaa !5
  %3 = add nsw i32 %2, -1
  store i32 %3, ptr @t, align 4, !tbaa !5
  %.not9 = icmp eq i32 %2, 0
  br i1 %.not9, label %._crit_edge12, label %.lr.ph11

.lr.ph11:                                         ; preds = %0, %._crit_edge8
  store i32 0, ptr @ans, align 4, !tbaa !5
  %4 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.1, ptr noundef nonnull @n, ptr noundef nonnull @m)
  %5 = load i32, ptr @n, align 4, !tbaa !5
  %6 = icmp sgt i32 %5, 0
  %7 = load i32, ptr @m, align 4
  %8 = icmp sgt i32 %7, 0
  %or.cond = select i1 %6, i1 %8, i1 false
  br i1 %or.cond, label %.preheader, label %._crit_edge8

.preheader:                                       ; preds = %.lr.ph11, %._crit_edge
  %9 = phi i32 [ %17, %._crit_edge ], [ %5, %.lr.ph11 ]
  %10 = phi i32 [ %18, %._crit_edge ], [ %7, %.lr.ph11 ]
  %.047 = phi i32 [ %19, %._crit_edge ], [ 0, %.lr.ph11 ]
  %11 = icmp sgt i32 %10, 0
  br i1 %11, label %.lr.ph, label %._crit_edge

._crit_edge8:                                     ; preds = %._crit_edge, %.lr.ph11
  %12 = load i32, ptr @ans, align 4, !tbaa !5
  %.not5 = icmp eq i32 %12, 0
  %13 = select i1 %.not5, ptr @.str.3, ptr @.str.2
  %14 = tail call i32 @puts(ptr noundef nonnull dereferenceable(1) %13)
  %15 = load i32, ptr @t, align 4, !tbaa !5
  %16 = add nsw i32 %15, -1
  store i32 %16, ptr @t, align 4, !tbaa !5
  %.not = icmp eq i32 %15, 0
  br i1 %.not, label %._crit_edge12, label %.lr.ph11, !llvm.loop !9

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

._crit_edge:                                      ; preds = %._crit_edge.loopexit, %.preheader
  %17 = phi i32 [ %.pre, %._crit_edge.loopexit ], [ %9, %.preheader ]
  %18 = phi i32 [ %26, %._crit_edge.loopexit ], [ %10, %.preheader ]
  %19 = add nuw nsw i32 %.047, 1
  %20 = icmp slt i32 %19, %17
  br i1 %20, label %.preheader, label %._crit_edge8, !llvm.loop !11

.lr.ph:                                           ; preds = %.preheader, %.lr.ph
  %.06 = phi i32 [ %25, %.lr.ph ], [ 0, %.preheader ]
  %21 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull @x)
  %22 = load i32, ptr @x, align 4, !tbaa !5
  %23 = load i32, ptr @ans, align 4, !tbaa !5
  %24 = xor i32 %23, %22
  store i32 %24, ptr @ans, align 4, !tbaa !5
  %25 = add nuw nsw i32 %.06, 1
  %26 = load i32, ptr @m, align 4, !tbaa !5
  %27 = icmp slt i32 %25, %26
  br i1 %27, label %.lr.ph, label %._crit_edge.loopexit, !llvm.loop !13

._crit_edge12:                                    ; preds = %._crit_edge8, %0
  ret i32 0
}

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

; Function Attrs: nofree nounwind
declare noundef i32 @puts(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"}
!11 = distinct !{!11, !10, !12}
!12 = !{!"llvm.loop.unswitch.partial.disable"}
!13 = distinct !{!13, !10}


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