; LLVM IR from Mohammed-Shoaib/Coding-Problems :: Codeforces/Solutions/1370D.ll (Z20odd_even_subsequenceiiRSt6vectorIiSaIiEE)

; 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.__gnu_cxx::__normal_iterator" = type { ptr }
%class.anon = type { ptr, ptr }

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z20odd_even_subsequenceiiRSt6vectorIiSaIiEE(i32 noundef %0, i32 noundef %1, ptr noundef nonnull align 8 dereferenceable(24) %2) #0 {
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca ptr, align 8
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  %9 = alloca i32, align 4
  %10 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %11 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %12 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %13 = alloca %class.anon, align 8
  store i32 %0, ptr %4, align 4, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !5
  store ptr %2, ptr %6, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #5
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #5
  store i32 0, ptr %8, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %9) #5
  call void @llvm.lifetime.start.p0(i64 8, ptr %10) #5
  %14 = load ptr, ptr %6, align 8, !tbaa !9
  %15 = call ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) %14) #5
  %16 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %11, i32 0, i32 0
  store ptr %15, ptr %16, align 8
  %17 = load ptr, ptr %6, align 8, !tbaa !9
  %18 = call ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24) %17) #5
  %19 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %12, i32 0, i32 0
  store ptr %18, ptr %19, align 8
  %20 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %11, i32 0, i32 0
  %21 = load ptr, ptr %20, align 8
  %22 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %12, i32 0, i32 0
  %23 = load ptr, ptr %22, align 8
  %24 = call ptr @_ZSt11max_elementIN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEEET_S7_S7_(ptr %21, ptr %23)
  %25 = getelementptr inbounds %"class.__gnu_cxx::__normal_iterator", ptr %10, i32 0, i32 0
  store ptr %24, ptr %25, align 8
  %26 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %10) #5
  %27 = load i32, ptr %26, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 8, ptr %10) #5
  store i32 %27, ptr %9, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 16, ptr %13) #5
  %28 = getelementptr inbounds %class.anon, ptr %13, i32 0, i32 0
  %29 = load ptr, ptr %6, align 8, !tbaa !9
  store ptr %29, ptr %28, align 8, !tbaa !9
  %30 = getelementptr inbounds %class.anon, ptr %13, i32 0, i32 1
  store ptr %5, ptr %30, align 8, !tbaa !9
  br label %31

31:                                               ; preds = %47, %3
  %32 = load i32, ptr %8, align 4, !tbaa !5
  %33 = load i32, ptr %9, align 4, !tbaa !5
  %34 = icmp slt i32 %32, %33
  br i1 %34, label %35, label %48

35:                                               ; preds = %31
  %36 = load i32, ptr %8, align 4, !tbaa !5
  %37 = load i32, ptr %9, align 4, !tbaa !5
  %38 = add nsw i32 %36, %37
  %39 = sdiv i32 %38, 2
  store i32 %39, ptr %7, align 4, !tbaa !5
  %40 = load i32, ptr %7, align 4, !tbaa !5
  %41 = call noundef zeroext i1 @"_ZZ20odd_even_subsequenceiiRSt6vectorIiSaIiEEENK3$_0clEi"(ptr noundef nonnull align 8 dereferenceable(16) %13, i32 noundef %40)
  br i1 %41, label %42, label %44

42:                                               ; preds = %35
  %43 = load i32, ptr %7, align 4, !tbaa !5
  store i32 %43, ptr %9, align 4, !tbaa !5
  br label %47

44:                                               ; preds = %35
  %45 = load i32, ptr %7, align 4, !tbaa !5
  %46 = add nsw i32 %45, 1
  store i32 %46, ptr %8, align 4, !tbaa !5
  br label %47

47:                                               ; preds = %44, %42
  br label %31, !llvm.loop !11

48:                                               ; preds = %31
  %49 = load i32, ptr %9, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 16, ptr %13) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr %9) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #5
  ret i32 %49
}

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: inlinehint mustprogress uwtable
declare dso_local ptr @_ZSt11max_elementIN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEEET_S7_S7_(ptr, ptr) #2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24)) #3 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24)) #3 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8)) #3 align 2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare hidden noundef zeroext i1 @"_ZZ20odd_even_subsequenceiiRSt6vectorIiSaIiEEENK3$_0clEi"(ptr noundef nonnull align 8 dereferenceable(16), i32 noundef) #4 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 = { inlinehint 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 #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 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !7, i64 0}
!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.__gnu_cxx::__normal_iterator" = type { ptr }
%class.anon = type { ptr, ptr }

; Function Attrs: mustprogress uwtable
define dso_local noundef range(i32 -2147483648, 1073741825) i32 @_Z20odd_even_subsequenceiiRSt6vectorIiSaIiEE(i32 noundef %0, i32 noundef %1, ptr noundef nonnull align 8 dereferenceable(24) %2) local_unnamed_addr #0 {
  %4 = alloca i32, align 4
  %5 = alloca %"class.__gnu_cxx::__normal_iterator", align 8
  %6 = alloca %class.anon, align 8
  store i32 %1, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %5) #5
  %7 = tail call ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24) %2) #5
  %8 = tail call ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24) %2) #5
  %9 = tail call ptr @_ZSt11max_elementIN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEEET_S7_S7_(ptr %7, ptr %8)
  store ptr %9, ptr %5, align 8
  %10 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8) %5) #5
  %11 = load i32, ptr %10, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %5) #5
  call void @llvm.lifetime.start.p0(i64 16, ptr nonnull %6) #5
  store ptr %2, ptr %6, align 8, !tbaa !9
  %12 = getelementptr inbounds i8, ptr %6, i64 8
  store ptr %4, ptr %12, align 8, !tbaa !9
  %13 = icmp sgt i32 %11, 0
  br i1 %13, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %3, %.lr.ph
  %.014 = phi i32 [ %.1, %.lr.ph ], [ 0, %3 ]
  %.01113 = phi i32 [ %.112, %.lr.ph ], [ %11, %3 ]
  %14 = add nuw nsw i32 %.014, %.01113
  %15 = lshr i32 %14, 1
  %16 = call noundef zeroext i1 @"_ZZ20odd_even_subsequenceiiRSt6vectorIiSaIiEEENK3$_0clEi"(ptr noundef nonnull align 8 dereferenceable(16) %6, i32 noundef %15)
  %17 = add nuw nsw i32 %15, 1
  %.112 = select i1 %16, i32 %15, i32 %.01113
  %.1 = select i1 %16, i32 %.014, i32 %17
  %18 = icmp slt i32 %.1, %.112
  br i1 %18, label %.lr.ph, label %._crit_edge, !llvm.loop !11

._crit_edge:                                      ; preds = %.lr.ph, %3
  %.011.lcssa = phi i32 [ %11, %3 ], [ %.112, %.lr.ph ]
  call void @llvm.lifetime.end.p0(i64 16, ptr nonnull %6) #5
  ret i32 %.011.lcssa
}

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: inlinehint mustprogress uwtable
declare dso_local ptr @_ZSt11max_elementIN9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEEET_S7_S7_(ptr, ptr) local_unnamed_addr #2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE5beginEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #3 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local ptr @_ZNSt6vectorIiSaIiEE3endEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #3 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZNK9__gnu_cxx17__normal_iteratorIPiSt6vectorIiSaIiEEEdeEv(ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #3 align 2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare hidden noundef zeroext i1 @"_ZZ20odd_even_subsequenceiiRSt6vectorIiSaIiEEENK3$_0clEi"(ptr noundef nonnull align 8 dereferenceable(16), i32 noundef) local_unnamed_addr #4 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 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 = { inlinehint 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 #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 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}


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