; LLVM IR from HarshCasper/NeoAlgo :: C-Plus-Plus/other (palindrome_linked_list)

; 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 }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }
%class.ListNode = type { i32, ptr }

@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [24 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [27 x i8], align 1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_Z13is_palindromeP8ListNode(ptr 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 norecurse uwtable
define dso_local noundef i32 @main() #2 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  %7 = alloca ptr, align 8
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #8
  %8 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %2)
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #8
  %9 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %3)
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #8
  %10 = call noalias noundef nonnull ptr @_Znwm(i64 noundef 16) #9
  call void @llvm.memset.p0.i64(ptr align 16 %10, i8 0, i64 16, i1 false)
  store ptr %10, ptr %4, align 8, !tbaa !5
  %11 = load i32, ptr %3, align 4, !tbaa !9
  %12 = load ptr, ptr %4, align 8, !tbaa !5
  %13 = getelementptr inbounds %class.ListNode, ptr %12, i32 0, i32 0
  store i32 %11, ptr %13, align 8, !tbaa !11
  %14 = load ptr, ptr %4, align 8, !tbaa !5
  %15 = getelementptr inbounds %class.ListNode, ptr %14, i32 0, i32 1
  store ptr null, ptr %15, align 8, !tbaa !13
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #8
  %16 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %16, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #8
  store i32 1, ptr %6, align 4, !tbaa !9
  br label %17

17:                                               ; preds = %33, %0
  %18 = load i32, ptr %6, align 4, !tbaa !9
  %19 = load i32, ptr %2, align 4, !tbaa !9
  %20 = icmp slt i32 %18, %19
  br i1 %20, label %22, label %21

21:                                               ; preds = %17
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #8
  br label %36

22:                                               ; preds = %17
  %23 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %3)
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #8
  %24 = call noalias noundef nonnull ptr @_Znwm(i64 noundef 16) #9
  call void @llvm.memset.p0.i64(ptr align 16 %24, i8 0, i64 16, i1 false)
  store ptr %24, ptr %7, align 8, !tbaa !5
  %25 = load i32, ptr %3, align 4, !tbaa !9
  %26 = load ptr, ptr %7, align 8, !tbaa !5
  %27 = getelementptr inbounds %class.ListNode, ptr %26, i32 0, i32 0
  store i32 %25, ptr %27, align 8, !tbaa !11
  %28 = load ptr, ptr %7, align 8, !tbaa !5
  %29 = getelementptr inbounds %class.ListNode, ptr %28, i32 0, i32 1
  store ptr null, ptr %29, align 8, !tbaa !13
  %30 = load ptr, ptr %7, align 8, !tbaa !5
  %31 = load ptr, ptr %5, align 8, !tbaa !5
  %32 = getelementptr inbounds %class.ListNode, ptr %31, i32 0, i32 1
  store ptr %30, ptr %32, align 8, !tbaa !13
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #8
  br label %33

33:                                               ; preds = %22
  %34 = load i32, ptr %6, align 4, !tbaa !9
  %35 = add nsw i32 %34, 1
  store i32 %35, ptr %6, align 4, !tbaa !9
  br label %17, !llvm.loop !14

36:                                               ; preds = %21
  %37 = load ptr, ptr %4, align 8, !tbaa !5
  %38 = call noundef zeroext i1 @_Z13is_palindromeP8ListNode(ptr noundef %37)
  br i1 %38, label %39, label %42

39:                                               ; preds = %36
  %40 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef @.str)
  %41 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %40, ptr noundef @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  br label %45

42:                                               ; preds = %36
  %43 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef @.str.1)
  %44 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %43, ptr noundef @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  br label %45

45:                                               ; preds = %42, %39
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #8
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #8
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #8
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #8
  %46 = load i32, ptr %1, align 4
  ret i32 %46
}

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) #3

; Function Attrs: nobuiltin allocsize(0)
declare noundef nonnull ptr @_Znwm(i64 noundef) #4

; Function Attrs: nocallback nofree nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #5

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #6

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #7 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_(ptr noundef nonnull align 8 dereferenceable(8)) #6

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 = { nobuiltin allocsize(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 = { nocallback nofree nounwind willreturn memory(argmem: write) }
attributes #6 = { 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 #7 = { 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 #8 = { nounwind }
attributes #9 = { builtin allocsize(0) }

!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 = !{!"int", !7, i64 0}
!11 = !{!12, !10, i64 0}
!12 = !{!"_ZTS8ListNode", !10, i64 0, !6, i64 8}
!13 = !{!12, !6, i64 8}
!14 = distinct !{!14, !15}
!15 = !{!"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::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 }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }

@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [24 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [27 x i8], align 1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_Z13is_palindromeP8ListNode(ptr noundef) local_unnamed_addr #0

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

; Function Attrs: mustprogress 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() local_unnamed_addr #2 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #8
  %3 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %1)
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #8
  %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) %2)
  %5 = call noalias noundef nonnull dereferenceable(16) ptr @_Znwm(i64 noundef 16) #9
  call void @llvm.memset.p0.i64(ptr noundef nonnull align 16 dereferenceable(16) %5, i8 0, i64 16, i1 false)
  %6 = load i32, ptr %2, align 4, !tbaa !5
  store i32 %6, ptr %5, align 8, !tbaa !9
  %7 = getelementptr inbounds i8, ptr %5, i64 8
  %8 = load i32, ptr %1, align 4, !tbaa !5
  %9 = icmp sgt i32 %8, 1
  br i1 %9, label %.lr.ph, label %._crit_edge

._crit_edge:                                      ; preds = %.lr.ph, %0
  %10 = call noundef zeroext i1 @_Z13is_palindromeP8ListNode(ptr noundef nonnull %5)
  %.str..str.1 = select i1 %10, ptr @.str, ptr @.str.1
  %11 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef nonnull %.str..str.1)
  %12 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8) %11, ptr noundef nonnull @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #8
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #8
  ret i32 0

.lr.ph:                                           ; preds = %0, %.lr.ph
  %.010 = phi i32 [ %16, %.lr.ph ], [ 1, %0 ]
  %13 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %2)
  %14 = call noalias noundef nonnull dereferenceable(16) ptr @_Znwm(i64 noundef 16) #9
  call void @llvm.memset.p0.i64(ptr noundef nonnull align 16 dereferenceable(16) %14, i8 0, i64 16, i1 false)
  %15 = load i32, ptr %2, align 4, !tbaa !5
  store i32 %15, ptr %14, align 8, !tbaa !9
  store ptr %14, ptr %7, align 8, !tbaa !12
  %16 = add nuw nsw i32 %.010, 1
  %17 = load i32, ptr %1, align 4, !tbaa !5
  %18 = icmp slt i32 %16, %17
  br i1 %18, label %.lr.ph, label %._crit_edge, !llvm.loop !13
}

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 #3

; Function Attrs: nobuiltin allocsize(0)
declare noundef nonnull ptr @_Znwm(i64 noundef) local_unnamed_addr #4

; Function Attrs: mustprogress nocallback nofree nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #5

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #6

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEPFRSoS_E(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #7 align 2

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6_(ptr noundef nonnull align 8 dereferenceable(8)) #6

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 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 = { nobuiltin allocsize(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 = { mustprogress nocallback nofree nounwind willreturn memory(argmem: write) }
attributes #6 = { 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 #7 = { 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 #8 = { nounwind }
attributes #9 = { builtin allocsize(0) }

!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 = !{!"_ZTS8ListNode", !6, i64 0, !11, i64 8}
!11 = !{!"any pointer", !7, i64 0}
!12 = !{!10, !11, i64 8}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: DSEPass,EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass