; LLVM IR from div-bargali/Data-Structures-and-Algorithms :: C++/Algorithms/Greedy-Algorithms (Is_Subsequence)

; 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: mustprogress uwtable
define dso_local noundef zeroext i1 @_Z13isSubsequenceNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES4_(ptr noundef %0, ptr noundef %1) #0 {
  %3 = alloca i1, align 1
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  %9 = alloca i8, align 1
  store ptr %0, ptr %4, align 8, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #3
  store i32 0, ptr %7, align 4, !tbaa !9
  %10 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #3
  %11 = icmp eq i64 %10, 0
  br i1 %11, label %12, label %13

12:                                               ; preds = %2
  store i1 true, ptr %3, align 1
  store i32 1, ptr %8, align 4
  br label %54

13:                                               ; preds = %2
  call void @llvm.lifetime.start.p0(i64 1, ptr %9) #3
  %14 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef 0)
  %15 = load i8, ptr %14, align 1, !tbaa !11
  store i8 %15, ptr %9, align 1, !tbaa !11
  %16 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %1) #3
  %17 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #3
  %18 = icmp ult i64 %16, %17
  br i1 %18, label %19, label %20

19:                                               ; preds = %13
  store i1 false, ptr %3, align 1
  store i32 1, ptr %8, align 4
  br label %53

20:                                               ; preds = %13
  store i32 0, ptr %6, align 4, !tbaa !9
  br label %21

21:                                               ; preds = %49, %20
  %22 = load i32, ptr %6, align 4, !tbaa !9
  %23 = sext i32 %22 to i64
  %24 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %1) #3
  %25 = icmp ult i64 %23, %24
  br i1 %25, label %26, label %52

26:                                               ; preds = %21
  %27 = load i32, ptr %6, align 4, !tbaa !9
  %28 = sext i32 %27 to i64
  %29 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef %28)
  %30 = load i8, ptr %29, align 1, !tbaa !11
  %31 = sext i8 %30 to i32
  %32 = load i8, ptr %9, align 1, !tbaa !11
  %33 = sext i8 %32 to i32
  %34 = icmp eq i32 %31, %33
  br i1 %34, label %35, label %48

35:                                               ; preds = %26
  %36 = load i32, ptr %7, align 4, !tbaa !9
  %37 = add nsw i32 %36, 1
  store i32 %37, ptr %7, align 4, !tbaa !9
  %38 = load i32, ptr %7, align 4, !tbaa !9
  %39 = sext i32 %38 to i64
  %40 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #3
  %41 = icmp eq i64 %39, %40
  br i1 %41, label %42, label %43

42:                                               ; preds = %35
  store i1 true, ptr %3, align 1
  store i32 1, ptr %8, align 4
  br label %53

43:                                               ; preds = %35
  %44 = load i32, ptr %7, align 4, !tbaa !9
  %45 = sext i32 %44 to i64
  %46 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %45)
  %47 = load i8, ptr %46, align 1, !tbaa !11
  store i8 %47, ptr %9, align 1, !tbaa !11
  br label %48

48:                                               ; preds = %43, %26
  br label %49

49:                                               ; preds = %48
  %50 = load i32, ptr %6, align 4, !tbaa !9
  %51 = add nsw i32 %50, 1
  store i32 %51, ptr %6, align 4, !tbaa !9
  br label %21, !llvm.loop !12

52:                                               ; preds = %21
  store i1 false, ptr %3, align 1
  store i32 1, ptr %8, align 4
  br label %53

53:                                               ; preds = %52, %42, %19
  call void @llvm.lifetime.end.p0(i64 1, ptr %9) #3
  br label %54

54:                                               ; preds = %53, %12
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #3
  %55 = load i1, ptr %3, align 1
  ret i1 %55
}

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

; Function Attrs: mustprogress nounwind uwtable
declare noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32)) #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: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

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 = { 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 = !{!10, !10, i64 0}
!10 = !{!"int", !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
define dso_local noundef zeroext i1 @_Z13isSubsequenceNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES4_(ptr noundef nonnull %0, ptr noundef %1) local_unnamed_addr #0 {
  %3 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #1
  %4 = icmp eq i64 %3, 0
  br i1 %4, label %.loopexit, label %5

5:                                                ; preds = %2
  %6 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef 0)
  %7 = load i8, ptr %6, align 1, !tbaa !5
  %8 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %1) #1
  %9 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #1
  %10 = icmp ult i64 %8, %9
  br i1 %10, label %.loopexit, label %.preheader

.preheader:                                       ; preds = %5
  %11 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %1) #1
  %.not = icmp eq i64 %11, 0
  br i1 %.not, label %.loopexit, label %.lr.ph

.lr.ph:                                           ; preds = %.preheader, %23
  %indvars.iv = phi i64 [ %indvars.iv.next, %23 ], [ 0, %.preheader ]
  %.016 = phi i8 [ %.1, %23 ], [ %7, %.preheader ]
  %.0715 = phi i32 [ %.18, %23 ], [ 0, %.preheader ]
  %12 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %1, i64 noundef %indvars.iv)
  %13 = load i8, ptr %12, align 1, !tbaa !5
  %14 = icmp eq i8 %13, %.016
  br i1 %14, label %15, label %23

15:                                               ; preds = %.lr.ph
  %16 = add nsw i32 %.0715, 1
  %17 = sext i32 %16 to i64
  %18 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #1
  %19 = icmp eq i64 %18, %17
  br i1 %19, label %.loopexit, label %20

20:                                               ; preds = %15
  %21 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %17)
  %22 = load i8, ptr %21, align 1, !tbaa !5
  br label %23

23:                                               ; preds = %.lr.ph, %20
  %.18 = phi i32 [ %16, %20 ], [ %.0715, %.lr.ph ]
  %.1 = phi i8 [ %22, %20 ], [ %.016, %.lr.ph ]
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %24 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %1) #1
  %25 = icmp ugt i64 %24, %indvars.iv.next
  br i1 %25, label %.lr.ph, label %.loopexit, !llvm.loop !8

.loopexit:                                        ; preds = %23, %15, %.preheader, %5, %2
  %.111 = phi i1 [ true, %2 ], [ false, %5 ], [ false, %.preheader ], [ false, %23 ], [ true, %15 ]
  ret i1 %.111
}

; Function Attrs: mustprogress nounwind uwtable
declare noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(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

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 = !{!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: EarlyCSEPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass