; LLVM IR from DionysiosB/CodeForces :: 0900-0999 (981A-Antipalindrome)

; 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"

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress nounwind uwtable
declare noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32)) #1 align 2

; Function Attrs: mustprogress nounwind uwtable
declare noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32), i64 noundef) #1 align 2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress uwtable
define dso_local noundef zeroext i1 @_Z7allSameNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE(ptr noundef %0) #2 {
  %2 = alloca i1, align 1
  %3 = alloca ptr, align 8
  %4 = alloca i64, align 8
  %5 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #3
  store i64 1, ptr %4, align 8, !tbaa !9
  br label %6

6:                                                ; preds = %22, %1
  %7 = load i64, ptr %4, align 8, !tbaa !9
  %8 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #3
  %9 = icmp ult i64 %7, %8
  br i1 %9, label %11, label %10

10:                                               ; preds = %6
  store i32 2, ptr %5, align 4
  br label %25

11:                                               ; preds = %6
  %12 = load i64, ptr %4, align 8, !tbaa !9
  %13 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %12)
  %14 = load i8, ptr %13, align 1, !tbaa !11
  %15 = sext i8 %14 to i32
  %16 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef 0)
  %17 = load i8, ptr %16, align 1, !tbaa !11
  %18 = sext i8 %17 to i32
  %19 = icmp ne i32 %15, %18
  br i1 %19, label %20, label %21

20:                                               ; preds = %11
  store i1 false, ptr %2, align 1
  store i32 1, ptr %5, align 4
  br label %25

21:                                               ; preds = %11
  br label %22

22:                                               ; preds = %21
  %23 = load i64, ptr %4, align 8, !tbaa !9
  %24 = add nsw i64 %23, 1
  store i64 %24, ptr %4, align 8, !tbaa !9
  br label %6, !llvm.loop !12

25:                                               ; preds = %20, %10
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #3
  %26 = load i32, ptr %5, align 4
  switch i32 %26, label %30 [
    i32 2, label %27
    i32 1, label %28
  ]

27:                                               ; preds = %25
  store i1 true, ptr %2, align 1
  br label %28

28:                                               ; preds = %27, %25
  %29 = load i1, ptr %2, align 1
  ret i1 %29

30:                                               ; preds = %25
  unreachable
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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 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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"long", !7, i64 0}
!11 = !{!7, !7, 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"

; Function Attrs: mustprogress nounwind uwtable
declare noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32)) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress nounwind uwtable
declare noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32), i64 noundef) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef zeroext i1 @_Z7allSameNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE(ptr noundef nonnull %0) local_unnamed_addr #0 {
  %2 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #1
  %3 = icmp ult i64 %2, 2
  br i1 %3, label %._crit_edge, label %.lr.ph

4:                                                ; preds = %.lr.ph
  %5 = add nuw nsw i64 %.046, 1
  %6 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #1
  %.not9 = icmp ult i64 %5, %6
  br i1 %.not9, label %.lr.ph, label %._crit_edge, !llvm.loop !5

.lr.ph:                                           ; preds = %1, %4
  %.046 = phi i64 [ %5, %4 ], [ 1, %1 ]
  %7 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %.046)
  %8 = load i8, ptr %7, align 1, !tbaa !7
  %9 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef 0)
  %10 = load i8, ptr %9, align 1, !tbaa !7
  %.not = icmp eq i8 %8, %10
  br i1 %.not, label %4, label %._crit_edge

._crit_edge:                                      ; preds = %4, %.lr.ph, %1
  %.lcssa = phi i1 [ true, %1 ], [ %.not, %.lr.ph ], [ %.not, %4 ]
  ret i1 %.lcssa
}

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 = { 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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}
!7 = !{!8, !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}


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