; LLVM IR from upupming/algorithm :: acwing/算法竞赛进阶指南/0x08-总结与练习/120. 防线 (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"

%"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 }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }

@t = external dso_local global i32, align 4
@n = external dso_local global i32, align 4
@s = external dso_local global [200010 x i32], align 16
@e = external dso_local global [200010 x i32], align 16
@d = external dso_local global [200010 x i32], align 16
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [21 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [2 x i8], align 1

; Function Attrs: mustprogress uwtable
declare dso_local noundef i32 @_Z3cnti(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
  %4 = alloca i32, align 4
  %5 = alloca i8, align 1
  %6 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  %7 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) @t)
  br label %8

8:                                                ; preds = %73, %0
  %9 = load i32, ptr @t, align 4, !tbaa !5
  %10 = add nsw i32 %9, -1
  store i32 %10, ptr @t, align 4, !tbaa !5
  %11 = icmp ne i32 %9, 0
  br i1 %11, label %12, label %74

12:                                               ; preds = %8
  %13 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) @n)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #5
  store i32 0, ptr %2, align 4, !tbaa !5
  br label %14

14:                                               ; preds = %32, %12
  %15 = load i32, ptr %2, align 4, !tbaa !5
  %16 = load i32, ptr @n, align 4, !tbaa !5
  %17 = icmp slt i32 %15, %16
  br i1 %17, label %19, label %18

18:                                               ; preds = %14
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #5
  br label %35

19:                                               ; preds = %14
  %20 = load i32, ptr %2, align 4, !tbaa !5
  %21 = sext i32 %20 to i64
  %22 = getelementptr inbounds [200010 x i32], ptr @s, i64 0, i64 %21
  %23 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %22)
  %24 = load i32, ptr %2, align 4, !tbaa !5
  %25 = sext i32 %24 to i64
  %26 = getelementptr inbounds [200010 x i32], ptr @e, i64 0, i64 %25
  %27 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) %23, ptr noundef nonnull align 4 dereferenceable(4) %26)
  %28 = load i32, ptr %2, align 4, !tbaa !5
  %29 = sext i32 %28 to i64
  %30 = getelementptr inbounds [200010 x i32], ptr @d, i64 0, i64 %29
  %31 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) %27, ptr noundef nonnull align 4 dereferenceable(4) %30)
  br label %32

32:                                               ; preds = %19
  %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 %14, !llvm.loop !9

35:                                               ; preds = %18
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #5
  store i32 1, ptr %3, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #5
  store i32 1073741823, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 1, ptr %5) #5
  store i8 1, ptr %5, align 1, !tbaa !11
  br label %36

36:                                               ; preds = %54, %35
  %37 = load i32, ptr %3, align 4, !tbaa !5
  %38 = load i32, ptr %4, align 4, !tbaa !5
  %39 = icmp slt i32 %37, %38
  br i1 %39, label %40, label %55

40:                                               ; preds = %36
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #5
  %41 = load i32, ptr %3, align 4, !tbaa !5
  %42 = load i32, ptr %4, align 4, !tbaa !5
  %43 = add nsw i32 %41, %42
  %44 = ashr i32 %43, 1
  store i32 %44, ptr %6, align 4, !tbaa !5
  %45 = load i32, ptr %6, align 4, !tbaa !5
  %46 = call noundef i32 @_Z3cnti(i32 noundef %45)
  %47 = srem i32 %46, 2
  %48 = icmp eq i32 %47, 0
  br i1 %48, label %49, label %52

49:                                               ; preds = %40
  %50 = load i32, ptr %6, align 4, !tbaa !5
  %51 = add nsw i32 %50, 1
  store i32 %51, ptr %3, align 4, !tbaa !5
  br label %54

52:                                               ; preds = %40
  %53 = load i32, ptr %6, align 4, !tbaa !5
  store i32 %53, ptr %4, align 4, !tbaa !5
  store i8 0, ptr %5, align 1, !tbaa !11
  br label %54

54:                                               ; preds = %52, %49
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #5
  br label %36, !llvm.loop !13

55:                                               ; preds = %36
  %56 = load i8, ptr %5, align 1, !tbaa !11, !range !14, !noundef !15
  %57 = trunc i8 %56 to i1
  br i1 %57, label %58, label %61

58:                                               ; preds = %55
  %59 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef @.str)
  %60 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %59, ptr noundef @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  br label %73

61:                                               ; preds = %55
  %62 = load i32, ptr %3, align 4, !tbaa !5
  %63 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %62)
  %64 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) %63, ptr noundef @.str.1)
  %65 = load i32, ptr %3, align 4, !tbaa !5
  %66 = call noundef i32 @_Z3cnti(i32 noundef %65)
  %67 = load i32, ptr %3, align 4, !tbaa !5
  %68 = sub nsw i32 %67, 1
  %69 = call noundef i32 @_Z3cnti(i32 noundef %68)
  %70 = sub nsw i32 %66, %69
  %71 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) %64, i32 noundef %70)
  %72 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %71, ptr noundef @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  br label %73

73:                                               ; preds = %61, %58
  call void @llvm.lifetime.end.p0(i64 1, ptr %5) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #5
  br label %8, !llvm.loop !16

74:                                               ; preds = %8
  ret i32 0
}

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

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #4

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #0 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_(ptr noundef nonnull align 8 dereferenceable(8)) #4

declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) #3

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 = { inlinehint 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 #5 = { 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 = !{!12, !12, i64 0}
!12 = !{!"bool", !7, i64 0}
!13 = distinct !{!13, !10}
!14 = !{i8 0, i8 2}
!15 = !{}
!16 = distinct !{!16, !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"

%"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 }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }

@t = external dso_local global i32, align 4
@n = external dso_local global i32, align 4
@s = external dso_local global [200010 x i32], align 16
@e = external dso_local global [200010 x i32], align 16
@d = external dso_local global [200010 x i32], align 16
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [21 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [2 x i8], align 1

; Function Attrs: mustprogress uwtable
declare dso_local noundef i32 @_Z3cnti(i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #1 {
  %1 = 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) @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
  %.not25 = icmp eq i32 %2, 0
  br i1 %.not25, label %._crit_edge, label %.lr.ph26

.lr.ph26:                                         ; preds = %0, %34
  %4 = 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) @n)
  %5 = load i32, ptr @n, align 4, !tbaa !5
  %6 = icmp sgt i32 %5, 0
  br i1 %6, label %.lr.ph, label %.preheader.preheader

.lr.ph:                                           ; preds = %.lr.ph26, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %.lr.ph26 ]
  %7 = getelementptr inbounds [200010 x i32], ptr @s, i64 0, i64 %indvars.iv
  %8 = 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) %7)
  %9 = getelementptr inbounds [200010 x i32], ptr @e, i64 0, i64 %indvars.iv
  %10 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) %8, ptr noundef nonnull align 4 dereferenceable(4) %9)
  %11 = getelementptr inbounds [200010 x i32], ptr @d, i64 0, i64 %indvars.iv
  %12 = tail call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) %10, ptr noundef nonnull align 4 dereferenceable(4) %11)
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %13 = load i32, ptr @n, align 4, !tbaa !5
  %14 = sext i32 %13 to i64
  %15 = icmp slt i64 %indvars.iv.next, %14
  br i1 %15, label %.lr.ph, label %.preheader.preheader, !llvm.loop !9

.preheader.preheader:                             ; preds = %.lr.ph, %.lr.ph26
  br label %.preheader

.preheader:                                       ; preds = %.preheader.preheader, %.preheader
  %.01624 = phi i1 [ %.1, %.preheader ], [ true, %.preheader.preheader ]
  %.01723 = phi i32 [ %.118, %.preheader ], [ 1073741823, %.preheader.preheader ]
  %.01922 = phi i32 [ %.120, %.preheader ], [ 1, %.preheader.preheader ]
  %16 = add nsw i32 %.01723, %.01922
  %17 = ashr i32 %16, 1
  %18 = tail call noundef i32 @_Z3cnti(i32 noundef %17)
  %19 = and i32 %18, 1
  %20 = icmp eq i32 %19, 0
  %21 = add nsw i32 %17, 1
  %.120 = select i1 %20, i32 %21, i32 %.01922
  %.118 = select i1 %20, i32 %.01723, i32 %17
  %.1 = select i1 %20, i1 %.01624, i1 false
  %22 = icmp slt i32 %.120, %.118
  br i1 %22, label %.preheader, label %23, !llvm.loop !11

23:                                               ; preds = %.preheader
  br i1 %.1, label %24, label %26

24:                                               ; preds = %23
  %25 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef nonnull @.str)
  br label %34

26:                                               ; preds = %23
  %27 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %.120)
  %28 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) %27, ptr noundef nonnull @.str.1)
  %29 = tail call noundef i32 @_Z3cnti(i32 noundef %.120)
  %30 = add nsw i32 %.120, -1
  %31 = tail call noundef i32 @_Z3cnti(i32 noundef %30)
  %32 = sub nsw i32 %29, %31
  %33 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) %28, i32 noundef %32)
  br label %34

34:                                               ; preds = %26, %24
  %.sink = phi ptr [ %33, %26 ], [ %25, %24 ]
  %35 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %.sink, ptr noundef nonnull @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  %36 = load i32, ptr @t, align 4, !tbaa !5
  %37 = add nsw i32 %36, -1
  store i32 %37, ptr @t, align 4, !tbaa !5
  %.not = icmp eq i32 %36, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph26, !llvm.loop !12

._crit_edge:                                      ; preds = %34, %0
  ret i32 0
}

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 #2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #3

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #0 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_(ptr noundef nonnull align 8 dereferenceable(8)) #3

declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) local_unnamed_addr #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 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 #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 = { inlinehint 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" }

!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}


; Effective O3 passes: AggressiveInstCombinePass,EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass