; LLVM IR from upupming/algorithm :: acwing/算法竞赛进阶指南/0x29-总结与练习/187. 导弹防御系统 (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" }

@n = external dso_local global i32, align 4
@a = external dso_local global [60 x i32], align 16
@e = external dso_local global i32, align 4
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8

; Function Attrs: mustprogress uwtable
declare dso_local noundef zeroext i1 @_Z3dfsiii(i32 noundef, i32 noundef, 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
  store i32 0, ptr %1, align 4
  br label %3

3:                                                ; preds = %36, %0
  %4 = 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 ptr, ptr %4, align 8, !tbaa !5
  %6 = getelementptr i8, ptr %5, i64 -24
  %7 = load i64, ptr %6, align 8
  %8 = getelementptr inbounds i8, ptr %4, i64 %7
  %9 = call noundef zeroext i1 @_ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv(ptr noundef nonnull align 8 dereferenceable(264) %8)
  br i1 %9, label %10, label %13

10:                                               ; preds = %3
  %11 = load i32, ptr @n, align 4, !tbaa !8
  %12 = icmp ne i32 %11, 0
  br label %13

13:                                               ; preds = %10, %3
  %14 = phi i1 [ false, %3 ], [ %12, %10 ]
  br i1 %14, label %15, label %40

15:                                               ; preds = %13
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #5
  store i32 0, ptr %2, align 4, !tbaa !8
  br label %16

16:                                               ; preds = %26, %15
  %17 = load i32, ptr %2, align 4, !tbaa !8
  %18 = load i32, ptr @n, align 4, !tbaa !8
  %19 = icmp slt i32 %17, %18
  br i1 %19, label %21, label %20

20:                                               ; preds = %16
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #5
  br label %29

21:                                               ; preds = %16
  %22 = load i32, ptr %2, align 4, !tbaa !8
  %23 = sext i32 %22 to i64
  %24 = getelementptr inbounds [60 x i32], ptr @a, i64 0, i64 %23
  %25 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %24)
  br label %26

26:                                               ; preds = %21
  %27 = load i32, ptr %2, align 4, !tbaa !8
  %28 = add nsw i32 %27, 1
  store i32 %28, ptr %2, align 4, !tbaa !8
  br label %16, !llvm.loop !11

29:                                               ; preds = %20
  store i32 1, ptr @e, align 4, !tbaa !8
  br label %30

30:                                               ; preds = %33, %29
  %31 = call noundef zeroext i1 @_Z3dfsiii(i32 noundef 0, i32 noundef 0, i32 noundef 0)
  %32 = xor i1 %31, true
  br i1 %32, label %33, label %36

33:                                               ; preds = %30
  %34 = load i32, ptr @e, align 4, !tbaa !8
  %35 = add nsw i32 %34, 1
  store i32 %35, ptr @e, align 4, !tbaa !8
  br label %30, !llvm.loop !13

36:                                               ; preds = %30
  %37 = load i32, ptr @e, align 4, !tbaa !8
  %38 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %37)
  %39 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %38, ptr noundef @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  br label %3, !llvm.loop !14

40:                                               ; preds = %13
  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: mustprogress uwtable
declare noundef zeroext i1 @_ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv(ptr noundef nonnull align 8 dereferenceable(264)) #0 align 2

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

; 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

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 = !{!"vtable pointer", !7, i64 0}
!7 = !{!"Simple C++ TBAA"}
!8 = !{!9, !9, i64 0}
!9 = !{!"int", !10, i64 0}
!10 = !{!"omnipotent char", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = distinct !{!13, !12}
!14 = distinct !{!14, !12}


; 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" }

@n = external dso_local global i32, align 4
@a = external dso_local global [60 x i32], align 16
@e = external dso_local local_unnamed_addr global i32, align 4
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8

; Function Attrs: mustprogress uwtable
declare dso_local noundef zeroext i1 @_Z3dfsiii(i32 noundef, i32 noundef, 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) @n)
  %2 = load ptr, ptr %1, align 8, !tbaa !5
  %3 = getelementptr i8, ptr %2, i64 -24
  %4 = load i64, ptr %3, align 8
  %5 = getelementptr inbounds i8, ptr %1, i64 %4
  %6 = tail call noundef zeroext i1 @_ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv(ptr noundef nonnull align 8 dereferenceable(264) %5)
  %7 = load i32, ptr @n, align 4
  %8 = icmp ne i32 %7, 0
  %9 = select i1 %6, i1 %8, i1 false
  br i1 %9, label %.preheader3, label %._crit_edge6

.preheader3:                                      ; preds = %0, %._crit_edge
  %10 = phi i32 [ %30, %._crit_edge ], [ %7, %0 ]
  %11 = icmp sgt i32 %10, 0
  br i1 %11, label %.lr.ph, label %.preheader

.preheader:                                       ; preds = %.lr.ph, %.preheader3
  store i32 1, ptr @e, align 4, !tbaa !8
  %12 = tail call noundef zeroext i1 @_Z3dfsiii(i32 noundef 0, i32 noundef 0, i32 noundef 0)
  br i1 %12, label %._crit_edge, label %.lr.ph5

.lr.ph:                                           ; preds = %.preheader3, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %.preheader3 ]
  %13 = getelementptr inbounds [60 x i32], ptr @a, i64 0, i64 %indvars.iv
  %14 = 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) %13)
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %15 = load i32, ptr @n, align 4, !tbaa !8
  %16 = sext i32 %15 to i64
  %17 = icmp slt i64 %indvars.iv.next, %16
  br i1 %17, label %.lr.ph, label %.preheader, !llvm.loop !11

.lr.ph5:                                          ; preds = %.preheader, %.lr.ph5
  %18 = load i32, ptr @e, align 4, !tbaa !8
  %19 = add nsw i32 %18, 1
  store i32 %19, ptr @e, align 4, !tbaa !8
  %20 = tail call noundef zeroext i1 @_Z3dfsiii(i32 noundef 0, i32 noundef 0, i32 noundef 0)
  br i1 %20, label %._crit_edge, label %.lr.ph5, !llvm.loop !13

._crit_edge:                                      ; preds = %.lr.ph5, %.preheader
  %21 = load i32, ptr @e, align 4, !tbaa !8
  %22 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %21)
  %23 = tail call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %22, ptr noundef nonnull @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  %24 = 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)
  %25 = load ptr, ptr %24, align 8, !tbaa !5
  %26 = getelementptr i8, ptr %25, i64 -24
  %27 = load i64, ptr %26, align 8
  %28 = getelementptr inbounds i8, ptr %24, i64 %27
  %29 = tail call noundef zeroext i1 @_ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv(ptr noundef nonnull align 8 dereferenceable(264) %28)
  %30 = load i32, ptr @n, align 4
  %31 = icmp ne i32 %30, 0
  %32 = select i1 %29, i1 %31, i1 false
  br i1 %32, label %.preheader3, label %._crit_edge6, !llvm.loop !14

._crit_edge6:                                     ; preds = %._crit_edge, %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: mustprogress uwtable
declare noundef zeroext i1 @_ZNKSt9basic_iosIcSt11char_traitsIcEEcvbEv(ptr noundef nonnull align 8 dereferenceable(264)) local_unnamed_addr #0 align 2

declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) local_unnamed_addr #2

; 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

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 = !{!"vtable pointer", !7, i64 0}
!7 = !{!"Simple C++ TBAA"}
!8 = !{!9, !9, i64 0}
!9 = !{!"int", !10, i64 0}
!10 = !{!"omnipotent char", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = distinct !{!13, !12}
!14 = distinct !{!14, !12}


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