; LLVM IR from Izaron/ACM-ICPC :: Timus Online Judge/Volume 1/1037. Memory Management.ll (Z9clear_oldi)

; 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::set" = type { %"class.std::_Rb_tree" }
%"class.std::_Rb_tree" = type { %"struct.std::_Rb_tree<int, int, std::_Identity<int>, std::less<int>>::_Rb_tree_impl" }
%"struct.std::_Rb_tree<int, int, std::_Identity<int>, std::less<int>>::_Rb_tree_impl" = type { [8 x i8], %"struct.std::_Rb_tree_header" }
%"struct.std::_Rb_tree_header" = type { %"struct.std::_Rb_tree_node_base", i64 }
%"struct.std::_Rb_tree_node_base" = type { i32, ptr, ptr, ptr }
%"class.std::set.0" = type { %"class.std::_Rb_tree.1" }
%"class.std::_Rb_tree.1" = type { %"struct.std::_Rb_tree<std::pair<int, int>, std::pair<int, int>, std::_Identity<std::pair<int, int>>, std::less<std::pair<int, int>>>::_Rb_tree_impl" }
%"struct.std::_Rb_tree<std::pair<int, int>, std::pair<int, int>, std::_Identity<std::pair<int, int>>, std::less<std::pair<int, int>>>::_Rb_tree_impl" = type { [8 x i8], %"struct.std::_Rb_tree_header" }
%"struct.std::pair" = type { i32, i32 }
%"struct.std::_Rb_tree_const_iterator" = type { ptr }
%"struct.std::pair.6" = type <{ %"struct.std::_Rb_tree_const_iterator.8", i8, [7 x i8] }>
%"struct.std::_Rb_tree_const_iterator.8" = type { ptr }

@free_blocks = external dso_local global %"class.std::set", align 8
@q = external dso_local global %"class.std::set.0", align 8

; Function Attrs: mustprogress uwtable
define dso_local void @_Z9clear_oldi(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca %"struct.std::pair", align 4
  %4 = alloca %"struct.std::_Rb_tree_const_iterator", align 8
  %5 = alloca %"struct.std::pair.6", align 8
  %6 = alloca i32, align 4
  store i32 %0, ptr %2, align 4, !tbaa !5
  br label %7

7:                                                ; preds = %31, %1
  %8 = call noundef zeroext i1 @_ZNKSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5emptyEv(ptr noundef nonnull align 8 dereferenceable(48) @q) #4
  %9 = xor i1 %8, true
  br i1 %9, label %10, label %32

10:                                               ; preds = %7
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #4
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  %11 = call ptr @_ZNKSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(48) @q) #4
  %12 = getelementptr inbounds %"struct.std::_Rb_tree_const_iterator", ptr %4, i32 0, i32 0
  store ptr %11, ptr %12, align 8
  %13 = call noundef nonnull align 4 dereferenceable(8) ptr @_ZNKSt23_Rb_tree_const_iteratorISt4pairIiiEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %4) #4
  call void @llvm.memcpy.p0.p0.i64(ptr align 4 %3, ptr align 4 %13, i64 8, i1 false)
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  %14 = load i32, ptr %2, align 4, !tbaa !5
  %15 = getelementptr inbounds %"struct.std::pair", ptr %3, i32 0, i32 0
  %16 = load i32, ptr %15, align 4, !tbaa !9
  %17 = sub nsw i32 %14, %16
  %18 = icmp sge i32 %17, 600
  br i1 %18, label %19, label %27

19:                                               ; preds = %10
  %20 = call noundef i64 @_ZNSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5eraseERKS1_(ptr noundef nonnull align 8 dereferenceable(48) @q, ptr noundef nonnull align 4 dereferenceable(8) %3)
  %21 = getelementptr inbounds %"struct.std::pair", ptr %3, i32 0, i32 1
  %22 = call { ptr, i8 } @_ZNSt3setIiSt4lessIiESaIiEE6insertERKi(ptr noundef nonnull align 8 dereferenceable(48) @free_blocks, ptr noundef nonnull align 4 dereferenceable(4) %21)
  %23 = getelementptr inbounds { ptr, i8 }, ptr %5, i32 0, i32 0
  %24 = extractvalue { ptr, i8 } %22, 0
  store ptr %24, ptr %23, align 8
  %25 = getelementptr inbounds { ptr, i8 }, ptr %5, i32 0, i32 1
  %26 = extractvalue { ptr, i8 } %22, 1
  store i8 %26, ptr %25, align 8
  br label %28

27:                                               ; preds = %10
  store i32 3, ptr %6, align 4
  br label %29

28:                                               ; preds = %19
  store i32 0, ptr %6, align 4
  br label %29

29:                                               ; preds = %28, %27
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #4
  %30 = load i32, ptr %6, align 4
  switch i32 %30, label %33 [
    i32 0, label %31
    i32 3, label %32
  ]

31:                                               ; preds = %29
  br label %7, !llvm.loop !11

32:                                               ; preds = %29, %7
  ret void

33:                                               ; preds = %29
  unreachable
}

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZNKSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5emptyEv(ptr noundef nonnull align 8 dereferenceable(48)) #1 align 2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNKSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(48)) #1 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(8) ptr @_ZNKSt23_Rb_tree_const_iteratorISt4pairIiiEEdeEv(ptr noundef nonnull align 8 dereferenceable(8)) #1 align 2

; Function Attrs: nocallback nofree nounwind willreturn memory(argmem: readwrite)
declare void @llvm.memcpy.p0.p0.i64(ptr noalias nocapture writeonly, ptr noalias nocapture readonly, i64, i1 immarg) #3

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: mustprogress uwtable
declare dso_local noundef i64 @_ZNSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5eraseERKS1_(ptr noundef nonnull align 8 dereferenceable(48), ptr noundef nonnull align 4 dereferenceable(8)) #0 align 2

; Function Attrs: mustprogress uwtable
declare dso_local { ptr, i8 } @_ZNSt3setIiSt4lessIiESaIiEE6insertERKi(ptr noundef nonnull align 8 dereferenceable(48), ptr noundef nonnull align 4 dereferenceable(4)) #0 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 = { 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 #2 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #3 = { nocallback nofree nounwind willreturn memory(argmem: readwrite) }
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 0}
!10 = !{!"_ZTSSt4pairIiiE", !6, i64 0, !6, i64 4}
!11 = distinct !{!11, !12}
!12 = !{!"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::set" = type { %"class.std::_Rb_tree" }
%"class.std::_Rb_tree" = type { %"struct.std::_Rb_tree<int, int, std::_Identity<int>, std::less<int>>::_Rb_tree_impl" }
%"struct.std::_Rb_tree<int, int, std::_Identity<int>, std::less<int>>::_Rb_tree_impl" = type { [8 x i8], %"struct.std::_Rb_tree_header" }
%"struct.std::_Rb_tree_header" = type { %"struct.std::_Rb_tree_node_base", i64 }
%"struct.std::_Rb_tree_node_base" = type { i32, ptr, ptr, ptr }
%"class.std::set.0" = type { %"class.std::_Rb_tree.1" }
%"class.std::_Rb_tree.1" = type { %"struct.std::_Rb_tree<std::pair<int, int>, std::pair<int, int>, std::_Identity<std::pair<int, int>>, std::less<std::pair<int, int>>>::_Rb_tree_impl" }
%"struct.std::_Rb_tree<std::pair<int, int>, std::pair<int, int>, std::_Identity<std::pair<int, int>>, std::less<std::pair<int, int>>>::_Rb_tree_impl" = type { [8 x i8], %"struct.std::_Rb_tree_header" }
%"struct.std::pair" = type { i32, i32 }
%"struct.std::_Rb_tree_const_iterator" = type { ptr }

@free_blocks = external dso_local global %"class.std::set", align 8
@q = external dso_local global %"class.std::set.0", align 8

; Function Attrs: mustprogress uwtable
define dso_local void @_Z9clear_oldi(i32 noundef %0) local_unnamed_addr #0 {
  %2 = alloca %"struct.std::pair", align 8
  %3 = alloca %"struct.std::_Rb_tree_const_iterator", align 8
  %4 = tail call noundef zeroext i1 @_ZNKSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5emptyEv(ptr noundef nonnull align 8 dereferenceable(48) @q) #3
  br i1 %4, label %.loopexit, label %.lr.ph

.lr.ph:                                           ; preds = %1
  %5 = getelementptr inbounds i8, ptr %2, i64 4
  br label %6

6:                                                ; preds = %.lr.ph, %13
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %2) #3
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %3) #3
  %7 = call ptr @_ZNKSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(48) @q) #3
  store ptr %7, ptr %3, align 8
  %8 = call noundef nonnull align 4 dereferenceable(8) ptr @_ZNKSt23_Rb_tree_const_iteratorISt4pairIiiEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %3) #3
  %9 = load i64, ptr %8, align 4
  store i64 %9, ptr %2, align 8
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %3) #3
  %10 = trunc i64 %9 to i32
  %11 = sub nsw i32 %0, %10
  %12 = icmp sgt i32 %11, 599
  br i1 %12, label %13, label %.thread

.thread:                                          ; preds = %6
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %2) #3
  br label %.loopexit

13:                                               ; preds = %6
  %14 = call noundef i64 @_ZNSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5eraseERKS1_(ptr noundef nonnull align 8 dereferenceable(48) @q, ptr noundef nonnull align 4 dereferenceable(8) %2)
  %15 = call { ptr, i8 } @_ZNSt3setIiSt4lessIiESaIiEE6insertERKi(ptr noundef nonnull align 8 dereferenceable(48) @free_blocks, ptr noundef nonnull align 4 dereferenceable(4) %5)
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %2) #3
  %16 = call noundef zeroext i1 @_ZNKSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5emptyEv(ptr noundef nonnull align 8 dereferenceable(48) @q) #3
  br i1 %16, label %.loopexit, label %6

.loopexit:                                        ; preds = %13, %1, %.thread
  ret void
}

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZNKSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5emptyEv(ptr noundef nonnull align 8 dereferenceable(48)) local_unnamed_addr #1 align 2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNKSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5beginEv(ptr noundef nonnull align 8 dereferenceable(48)) local_unnamed_addr #1 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(8) ptr @_ZNKSt23_Rb_tree_const_iteratorISt4pairIiiEEdeEv(ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #1 align 2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: mustprogress uwtable
declare dso_local noundef i64 @_ZNSt3setISt4pairIiiESt4lessIS1_ESaIS1_EE5eraseERKS1_(ptr noundef nonnull align 8 dereferenceable(48), ptr noundef nonnull align 4 dereferenceable(8)) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress uwtable
declare dso_local { ptr, i8 } @_ZNSt3setIiSt4lessIiESaIiEE6insertERKi(ptr noundef nonnull align 8 dereferenceable(48), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #0 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 = { 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 #2 = { mustprogress 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)"}


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