; LLVM IR from HarshCasper/NeoAlgo :: C-Plus-Plus/math (SumOf_TwoLarge_numbers_represented_as_strings)

; 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::__cxx11::basic_string" = type { %"struct.std::__cxx11::basic_string<char>::_Alloc_hider", i64, %union.anon }
%"struct.std::__cxx11::basic_string<char>::_Alloc_hider" = type { ptr }
%union.anon = type { i64, [8 x i8] }

@.str = external hidden unnamed_addr constant [2 x i8], align 1

; Function Attrs: mustprogress uwtable
define dso_local void @_Z4trimNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE(ptr dead_on_unwind noalias writable sret(%"class.std::__cxx11::basic_string") align 8 %0, ptr noundef %1) #0 {
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  store ptr %0, ptr %3, align 8
  store ptr %1, ptr %4, align 8, !tbaa !5
  %5 = call noundef zeroext i1 @_ZSteqIcSt11char_traitsIcESaIcEEbRKNSt7__cxx1112basic_stringIT_T0_T1_EEPKS5_(ptr noundef nonnull align 8 dereferenceable(32) %1, ptr noundef @.str)
  br i1 %5, label %6, label %7

6:                                                ; preds = %2
  call void @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEC2EOS4_(ptr noundef nonnull align 8 dereferenceable(32) %0, ptr noundef nonnull align 8 dereferenceable(32) %1) #3
  br label %16

7:                                                ; preds = %2
  br label %8

8:                                                ; preds = %13, %7
  %9 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef 0)
  %10 = load i8, ptr %9, align 1, !tbaa !9
  %11 = sext i8 %10 to i32
  %12 = icmp eq i32 %11, 48
  br i1 %12, label %13, label %15

13:                                               ; preds = %8
  %14 = call noundef nonnull align 8 dereferenceable(32) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE5eraseEmm(ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef 0, i64 noundef 1)
  br label %8, !llvm.loop !10

15:                                               ; preds = %8
  call void @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEC2EOS4_(ptr noundef nonnull align 8 dereferenceable(32) %0, ptr noundef nonnull align 8 dereferenceable(32) %1) #3
  br label %16

16:                                               ; preds = %15, %6
  ret void
}

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZSteqIcSt11char_traitsIcESaIcEEbRKNSt7__cxx1112basic_stringIT_T0_T1_EEPKS5_(ptr noundef nonnull align 8 dereferenceable(32), ptr noundef) #1

; Function Attrs: mustprogress nounwind uwtable
declare void @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEC2EOS4_(ptr noundef nonnull align 8 dereferenceable(32), ptr noundef nonnull align 8 dereferenceable(32)) unnamed_addr #2 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) #2 align 2

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(32) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE5eraseEmm(ptr noundef nonnull align 8 dereferenceable(32), i64 noundef, i64 noundef) #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 = { 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 #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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!7, !7, i64 0}
!10 = distinct !{!10, !11}
!11 = !{!"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::__cxx11::basic_string" = type { %"struct.std::__cxx11::basic_string<char>::_Alloc_hider", i64, %union.anon }
%"struct.std::__cxx11::basic_string<char>::_Alloc_hider" = type { ptr }
%union.anon = type { i64, [8 x i8] }

@.str = external hidden unnamed_addr constant [2 x i8], align 1

; Function Attrs: mustprogress uwtable
define dso_local void @_Z4trimNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE(ptr dead_on_unwind noalias writable sret(%"class.std::__cxx11::basic_string") align 8 %0, ptr noundef nonnull %1) local_unnamed_addr #0 {
  %3 = tail call noundef zeroext i1 @_ZSteqIcSt11char_traitsIcESaIcEEbRKNSt7__cxx1112basic_stringIT_T0_T1_EEPKS5_(ptr noundef nonnull align 8 dereferenceable(32) %1, ptr noundef nonnull @.str)
  br i1 %3, label %._crit_edge, label %.preheader

.preheader:                                       ; preds = %2
  %4 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef 0)
  %5 = load i8, ptr %4, align 1, !tbaa !5
  %6 = icmp eq i8 %5, 48
  br i1 %6, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %.preheader, %.lr.ph
  %7 = tail call noundef nonnull align 8 dereferenceable(32) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE5eraseEmm(ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef 0, i64 noundef 1)
  %8 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef 0)
  %9 = load i8, ptr %8, align 1, !tbaa !5
  %10 = icmp eq i8 %9, 48
  br i1 %10, label %.lr.ph, label %._crit_edge, !llvm.loop !8

._crit_edge:                                      ; preds = %.lr.ph, %.preheader, %2
  tail call void @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEC2EOS4_(ptr noundef nonnull align 8 dereferenceable(32) %0, ptr noundef nonnull align 8 dereferenceable(32) %1) #3
  ret void
}

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_ZSteqIcSt11char_traitsIcESaIcEEbRKNSt7__cxx1112basic_stringIT_T0_T1_EEPKS5_(ptr noundef nonnull align 8 dereferenceable(32), ptr noundef) local_unnamed_addr #1

; Function Attrs: mustprogress nounwind uwtable
declare void @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEC2EOS4_(ptr noundef nonnull align 8 dereferenceable(32), ptr noundef nonnull align 8 dereferenceable(32)) unnamed_addr #2 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 #2 align 2

; Function Attrs: mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(32) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE5eraseEmm(ptr noundef nonnull align 8 dereferenceable(32), i64 noundef, i64 noundef) 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 = { 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 #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 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C++ TBAA"}
!8 = distinct !{!8, !9}
!9 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: GlobalOptPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass