; LLVM IR from sunkafei/xcpc-algorithm-templates :: 算法/图论/欧拉回路.ll (ZN12direct_graph5eulerEi)

; 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::vector.0" = type { %"struct.std::_Vector_base.1" }
%"struct.std::_Vector_base.1" = type { %"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl" }
%"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl" = type { %"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl_data" }
%"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl_data" = type { ptr, ptr, ptr }
%"class.__gnu_cxx::__normal_iterator" = type { ptr }
%"struct.std::pair" = type { i32, i32 }

@m = external dso_local global i32, align 4
@_ZN12direct_graph6resultE = external dso_local global %"class.std::vector.0", align 8

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZN12direct_graph3dfsEi(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 uwtable
define dso_local noundef zeroext i1 @_ZN12direct_graph5eulerEi(i32 noundef %0) #0 {
  %2 = alloca i1, align 1
  %3 = alloca i32, align 4
  %4 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %5 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  %8 = load i32, ptr %3, align 4, !tbaa !5
  call void @_ZN12direct_graph3dfsEi(i32 noundef %8)
  %9 = call ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #4
  %10 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %4, i32 0, i32 0
  store ptr %9, ptr %10, align 8
  %11 = call ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE3endEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #4
  %12 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %5, i32 0, i32 0
  store ptr %11, ptr %12, align 8
  %13 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %4, i32 0, i32 0
  %14 = load ptr, ptr %13, align 8
  %15 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %5, i32 0, i32 0
  %16 = load ptr, ptr %15, align 8
  call void @_ZSt7reverseIN9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS3_SaIS3_EEEEEvT_S9_(ptr %14, ptr %16)
  %17 = call noundef i64 @_ZNKSt6vectorISt4pairIiiESaIS1_EE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #4
  %18 = load i32, ptr @m, align 4, !tbaa !5
  %19 = sext i32 %18 to i64
  %20 = icmp ne i64 %17, %19
  br i1 %20, label %30, label %21

21:                                               ; preds = %1
  %22 = call noundef i64 @_ZNKSt6vectorISt4pairIiiESaIS1_EE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #4
  %23 = icmp ne i64 %22, 0
  br i1 %23, label %24, label %31

24:                                               ; preds = %21
  %25 = call noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE4backEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #4
  %26 = getelementptr inbounds %"struct.std::pair", ptr %25, i32 0, i32 1
  %27 = load i32, ptr %26, align 4, !tbaa !9
  %28 = load i32, ptr %3, align 4, !tbaa !5
  %29 = icmp ne i32 %27, %28
  br i1 %29, label %30, label %31

30:                                               ; preds = %24, %1
  store i1 false, ptr %2, align 1
  br label %59

31:                                               ; preds = %24, %21
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #4
  store i32 1, ptr %6, align 4, !tbaa !5
  br label %32

32:                                               ; preds = %53, %31
  %33 = load i32, ptr %6, align 4, !tbaa !5
  %34 = sext i32 %33 to i64
  %35 = call noundef i64 @_ZNKSt6vectorISt4pairIiiESaIS1_EE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #4
  %36 = icmp ult i64 %34, %35
  br i1 %36, label %38, label %37

37:                                               ; preds = %32
  store i32 2, ptr %7, align 4
  br label %56

38:                                               ; preds = %32
  %39 = load i32, ptr %6, align 4, !tbaa !5
  %40 = sub nsw i32 %39, 1
  %41 = sext i32 %40 to i64
  %42 = call noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorISt4pairIiiESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE, i64 noundef %41) #4
  %43 = getelementptr inbounds %"struct.std::pair", ptr %42, i32 0, i32 1
  %44 = load i32, ptr %43, align 4, !tbaa !9
  %45 = load i32, ptr %6, align 4, !tbaa !5
  %46 = sext i32 %45 to i64
  %47 = call noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorISt4pairIiiESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE, i64 noundef %46) #4
  %48 = getelementptr inbounds %"struct.std::pair", ptr %47, i32 0, i32 0
  %49 = load i32, ptr %48, align 4, !tbaa !11
  %50 = icmp ne i32 %44, %49
  br i1 %50, label %51, label %52

51:                                               ; preds = %38
  store i1 false, ptr %2, align 1
  store i32 1, ptr %7, align 4
  br label %56

52:                                               ; preds = %38
  br label %53

53:                                               ; preds = %52
  %54 = load i32, ptr %6, align 4, !tbaa !5
  %55 = add nsw i32 %54, 1
  store i32 %55, ptr %6, align 4, !tbaa !5
  br label %32, !llvm.loop !12

56:                                               ; preds = %51, %37
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #4
  %57 = load i32, ptr %7, align 4
  switch i32 %57, label %61 [
    i32 2, label %58
    i32 1, label %59
  ]

58:                                               ; preds = %56
  store i1 true, ptr %2, align 1
  br label %59

59:                                               ; preds = %58, %56, %30
  %60 = load i1, ptr %2, align 1
  ret i1 %60

61:                                               ; preds = %56
  unreachable
}

; Function Attrs: inlinehint mustprogress uwtable
declare dso_local void @_ZSt7reverseIN9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS3_SaIS3_EEEEEvT_S9_(ptr, ptr) #2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(24)) #3 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE3endEv(ptr noundef nonnull align 8 dereferenceable(24)) #3 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef i64 @_ZNKSt6vectorISt4pairIiiESaIS1_EE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24)) #3 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE4backEv(ptr noundef nonnull align 8 dereferenceable(24)) #3 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorISt4pairIiiESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef) #3 align 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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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 #3 = { 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 #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 = !{!10, !6, i64 4}
!10 = !{!"_ZTSSt4pairIiiE", !6, i64 0, !6, i64 4}
!11 = !{!10, !6, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"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"

%"class.std::vector.0" = type { %"struct.std::_Vector_base.1" }
%"struct.std::_Vector_base.1" = type { %"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl" }
%"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl" = type { %"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl_data" }
%"struct.std::_Vector_base<std::pair<int, int>, std::allocator<std::pair<int, int>>>::_Vector_impl_data" = type { ptr, ptr, ptr }

@m = external dso_local local_unnamed_addr global i32, align 4
@_ZN12direct_graph6resultE = external dso_local global %"class.std::vector.0", align 8

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZN12direct_graph3dfsEi(i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress uwtable
define dso_local noundef zeroext i1 @_ZN12direct_graph5eulerEi(i32 noundef %0) local_unnamed_addr #0 {
  tail call void @_ZN12direct_graph3dfsEi(i32 noundef %0)
  %2 = tail call ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #3
  %3 = tail call ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE3endEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #3
  tail call void @_ZSt7reverseIN9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS3_SaIS3_EEEEEvT_S9_(ptr %2, ptr %3)
  %4 = tail call noundef i64 @_ZNKSt6vectorISt4pairIiiESaIS1_EE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #3
  %5 = load i32, ptr @m, align 4, !tbaa !5
  %6 = sext i32 %5 to i64
  %.not = icmp eq i64 %4, %6
  br i1 %.not, label %7, label %.loopexit

7:                                                ; preds = %1
  %8 = tail call noundef i64 @_ZNKSt6vectorISt4pairIiiESaIS1_EE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #3
  %.not11 = icmp eq i64 %8, 0
  br i1 %.not11, label %13, label %9

9:                                                ; preds = %7
  %10 = tail call noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE4backEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #3
  %11 = getelementptr inbounds i8, ptr %10, i64 4
  %12 = load i32, ptr %11, align 4, !tbaa !9
  %.not12 = icmp eq i32 %12, %0
  br i1 %.not12, label %13, label %.loopexit

13:                                               ; preds = %9, %7
  %14 = tail call noundef i64 @_ZNKSt6vectorISt4pairIiiESaIS1_EE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #3
  %15 = icmp ult i64 %14, 2
  br i1 %15, label %.loopexit, label %.lr.ph

16:                                               ; preds = %.lr.ph
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %17 = tail call noundef i64 @_ZNKSt6vectorISt4pairIiiESaIS1_EE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE) #3
  %.not18 = icmp ugt i64 %17, %indvars.iv.next
  br i1 %.not18, label %.lr.ph, label %.loopexit, !llvm.loop !11

.lr.ph:                                           ; preds = %13, %16
  %indvars.iv = phi i64 [ %indvars.iv.next, %16 ], [ 1, %13 ]
  %18 = add nsw i64 %indvars.iv, -1
  %19 = tail call noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorISt4pairIiiESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE, i64 noundef %18) #3
  %20 = getelementptr inbounds i8, ptr %19, i64 4
  %21 = load i32, ptr %20, align 4, !tbaa !9
  %22 = tail call noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorISt4pairIiiESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24) @_ZN12direct_graph6resultE, i64 noundef %indvars.iv) #3
  %23 = load i32, ptr %22, align 4, !tbaa !13
  %.not13 = icmp eq i32 %21, %23
  br i1 %.not13, label %16, label %.loopexit

.loopexit:                                        ; preds = %.lr.ph, %16, %13, %1, %9
  %.1 = phi i1 [ false, %9 ], [ false, %1 ], [ true, %13 ], [ %.not13, %16 ], [ %.not13, %.lr.ph ]
  ret i1 %.1
}

; Function Attrs: inlinehint mustprogress uwtable
declare dso_local void @_ZSt7reverseIN9__gnu_cxx17__normal_iteratorIPSt4pairIiiESt6vectorIS3_SaIS3_EEEEEvT_S9_(ptr, ptr) local_unnamed_addr #1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE3endEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef i64 @_ZNKSt6vectorISt4pairIiiESaIS1_EE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorISt4pairIiiESaIS1_EE4backEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(8) ptr @_ZNSt6vectorISt4pairIiiESaIS1_EEixEm(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef) local_unnamed_addr #2 align 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 = { 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 #2 = { 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 #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 = !{!10, !6, i64 4}
!10 = !{!"_ZTSSt4pairIiiE", !6, i64 0, !6, i64 4}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = !{!10, !6, i64 0}


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