; LLVM IR from upupming/algorithm :: acwing/算法竞赛进阶指南/0x15-字符串/141. 周期 (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 }

@n = external dso_local global i32, align 4
@t = external dso_local global i32, align 4
@Next = external dso_local global [1000010 x i32], align 16
@s = external dso_local global [1000010 x i8], align 16
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@.str = external hidden unnamed_addr constant [3 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [15 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [7 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [1 x i8], align 1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_Z8calcNextv() #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 = %52, %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 i32, ptr @n, align 4, !tbaa !5
  %6 = icmp ne i32 %5, 0
  br i1 %6, label %7, label %54

7:                                                ; preds = %3
  %8 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef getelementptr inbounds (i8, ptr @s, i64 1))
  call void @_Z8calcNextv()
  %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 = call i32 (ptr, ...) @printf(ptr noundef @.str.1, i32 noundef %10)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #4
  store i32 2, ptr %2, align 4, !tbaa !5
  br label %12

12:                                               ; preds = %49, %7
  %13 = load i32, ptr %2, align 4, !tbaa !5
  %14 = load i32, ptr @n, align 4, !tbaa !5
  %15 = icmp sle i32 %13, %14
  br i1 %15, label %17, label %16

16:                                               ; preds = %12
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #4
  br label %52

17:                                               ; preds = %12
  %18 = load i32, ptr %2, align 4, !tbaa !5
  %19 = load i32, ptr %2, align 4, !tbaa !5
  %20 = load i32, ptr %2, align 4, !tbaa !5
  %21 = sext i32 %20 to i64
  %22 = getelementptr inbounds [1000010 x i32], ptr @Next, i64 0, i64 %21
  %23 = load i32, ptr %22, align 4, !tbaa !5
  %24 = sub nsw i32 %19, %23
  %25 = srem i32 %18, %24
  %26 = icmp eq i32 %25, 0
  br i1 %26, label %27, label %48

27:                                               ; preds = %17
  %28 = load i32, ptr %2, align 4, !tbaa !5
  %29 = load i32, ptr %2, align 4, !tbaa !5
  %30 = load i32, ptr %2, align 4, !tbaa !5
  %31 = sext i32 %30 to i64
  %32 = getelementptr inbounds [1000010 x i32], ptr @Next, i64 0, i64 %31
  %33 = load i32, ptr %32, align 4, !tbaa !5
  %34 = sub nsw i32 %29, %33
  %35 = sdiv i32 %28, %34
  %36 = icmp sgt i32 %35, 1
  br i1 %36, label %37, label %48

37:                                               ; preds = %27
  %38 = load i32, ptr %2, align 4, !tbaa !5
  %39 = load i32, ptr %2, align 4, !tbaa !5
  %40 = load i32, ptr %2, align 4, !tbaa !5
  %41 = load i32, ptr %2, align 4, !tbaa !5
  %42 = sext i32 %41 to i64
  %43 = getelementptr inbounds [1000010 x i32], ptr @Next, i64 0, i64 %42
  %44 = load i32, ptr %43, align 4, !tbaa !5
  %45 = sub nsw i32 %40, %44
  %46 = sdiv i32 %39, %45
  %47 = call i32 (ptr, ...) @printf(ptr noundef @.str.2, i32 noundef %38, i32 noundef %46)
  br label %48

48:                                               ; preds = %37, %27, %17
  br label %49

49:                                               ; preds = %48
  %50 = load i32, ptr %2, align 4, !tbaa !5
  %51 = add nsw i32 %50, 1
  store i32 %51, ptr %2, align 4, !tbaa !5
  br label %12, !llvm.loop !9

52:                                               ; preds = %16
  %53 = call i32 @puts(ptr noundef @.str.3)
  br label %3, !llvm.loop !11

54:                                               ; preds = %3
  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

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

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

declare i32 @puts(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"

%"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 }

@n = external dso_local global i32, align 4
@t = external dso_local local_unnamed_addr global i32, align 4
@Next = external dso_local local_unnamed_addr global [1000010 x i32], align 16
@s = external dso_local global [1000010 x i8], align 16
@_ZSt3cin = external global %"class.std::basic_istream", align 8
@.str = external hidden unnamed_addr constant [3 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [15 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [7 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [1 x i8], align 1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_Z8calcNextv() 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 i32, ptr @n, align 4, !tbaa !5
  %.not16 = icmp eq i32 %2, 0
  br i1 %.not16, label %._crit_edge19, label %.lr.ph18

.lr.ph18:                                         ; preds = %0, %._crit_edge
  %3 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull getelementptr inbounds (i8, ptr @s, i64 1))
  tail call void @_Z8calcNextv()
  %4 = load i32, ptr @t, align 4, !tbaa !5
  %5 = add nsw i32 %4, 1
  store i32 %5, ptr @t, align 4, !tbaa !5
  %6 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1, i32 noundef %5)
  %7 = load i32, ptr @n, align 4, !tbaa !5
  %.not1314 = icmp slt i32 %7, 2
  br i1 %.not1314, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %22, %.lr.ph18
  %8 = tail call i32 @puts(ptr noundef nonnull dereferenceable(1) @.str.3)
  %9 = 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)
  %10 = load i32, ptr @n, align 4, !tbaa !5
  %.not = icmp eq i32 %10, 0
  br i1 %.not, label %._crit_edge19, label %.lr.ph18, !llvm.loop !9

.lr.ph:                                           ; preds = %.lr.ph18, %22
  %11 = phi i32 [ %23, %22 ], [ %7, %.lr.ph18 ]
  %indvars.iv = phi i64 [ %indvars.iv.next, %22 ], [ 2, %.lr.ph18 ]
  %12 = getelementptr inbounds [1000010 x i32], ptr @Next, i64 0, i64 %indvars.iv
  %13 = load i32, ptr %12, align 4, !tbaa !5
  %14 = trunc nuw nsw i64 %indvars.iv to i32
  %15 = sub nsw i32 %14, %13
  %16 = srem i32 %14, %15
  %17 = sdiv i32 %14, %15
  %18 = icmp eq i32 %16, 0
  %19 = icmp sgt i32 %17, 1
  %or.cond = and i1 %18, %19
  br i1 %or.cond, label %20, label %22

20:                                               ; preds = %.lr.ph
  %21 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.2, i32 noundef %14, i32 noundef %17)
  %.pre = load i32, ptr @n, align 4, !tbaa !5
  br label %22

22:                                               ; preds = %.lr.ph, %20
  %23 = phi i32 [ %11, %.lr.ph ], [ %.pre, %20 ]
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %24 = sext i32 %23 to i64
  %.not13.not = icmp slt i64 %indvars.iv, %24
  br i1 %.not13.not, label %.lr.ph, label %._crit_edge, !llvm.loop !11

._crit_edge19:                                    ; 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: 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

; Function Attrs: nofree nounwind
declare noundef i32 @puts(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 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 = { 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}


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