; LLVM IR from Mohammed-Shoaib/Coding-Problems :: CodeChef/Beginner (B0087)

; 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 i32 @_Z18chefAndHisStudentsNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE(ptr noundef %0) #0 {
  %2 = alloca ptr, align 8
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #3
  store i32 0, ptr %3, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  store i32 0, ptr %4, align 4, !tbaa !9
  br label %5

5:                                                ; preds = %31, %1
  %6 = load i32, ptr %4, align 4, !tbaa !9
  %7 = sext i32 %6 to i64
  %8 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #3
  %9 = sub i64 %8, 1
  %10 = icmp ult i64 %7, %9
  br i1 %10, label %12, label %11

11:                                               ; preds = %5
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  br label %34

12:                                               ; preds = %5
  %13 = load i32, ptr %4, align 4, !tbaa !9
  %14 = sext i32 %13 to i64
  %15 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %14)
  %16 = load i8, ptr %15, align 1, !tbaa !11
  %17 = sext i8 %16 to i32
  %18 = icmp eq i32 %17, 60
  br i1 %18, label %19, label %30

19:                                               ; preds = %12
  %20 = load i32, ptr %4, align 4, !tbaa !9
  %21 = add nsw i32 %20, 1
  %22 = sext i32 %21 to i64
  %23 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %22)
  %24 = load i8, ptr %23, align 1, !tbaa !11
  %25 = sext i8 %24 to i32
  %26 = icmp eq i32 %25, 62
  br i1 %26, label %27, label %30

27:                                               ; preds = %19
  %28 = load i32, ptr %3, align 4, !tbaa !9
  %29 = add nsw i32 %28, 1
  store i32 %29, ptr %3, align 4, !tbaa !9
  br label %30

30:                                               ; preds = %27, %19, %12
  br label %31

31:                                               ; preds = %30
  %32 = load i32, ptr %4, align 4, !tbaa !9
  %33 = add nsw i32 %32, 1
  store i32 %33, ptr %4, align 4, !tbaa !9
  br label %5, !llvm.loop !12

34:                                               ; preds = %11
  %35 = load i32, ptr %3, align 4, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  ret i32 %35
}

; 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 i32 @_Z18chefAndHisStudentsNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE(ptr noundef nonnull %0) local_unnamed_addr #0 {
  %2 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #1
  %.not = icmp eq i64 %2, 1
  br i1 %.not, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %.lr.ph._crit_edge, %1
  %.06.lcssa = phi i32 [ 0, %1 ], [ %.1, %.lr.ph._crit_edge ]
  ret i32 %.06.lcssa

.lr.ph:                                           ; preds = %1, %.lr.ph._crit_edge
  %indvars.iv = phi i64 [ %6, %.lr.ph._crit_edge ], [ 0, %1 ]
  %.068 = phi i32 [ %.1, %.lr.ph._crit_edge ], [ 0, %1 ]
  %3 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %indvars.iv)
  %4 = load i8, ptr %3, align 1, !tbaa !5
  %5 = icmp eq i8 %4, 60
  %6 = add nuw nsw i64 %indvars.iv, 1
  br i1 %5, label %7, label %.lr.ph._crit_edge

7:                                                ; preds = %.lr.ph
  %8 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %6)
  %9 = load i8, ptr %8, align 1, !tbaa !5
  %10 = icmp eq i8 %9, 62
  %11 = zext i1 %10 to i32
  %spec.select = add nsw i32 %.068, %11
  br label %.lr.ph._crit_edge

.lr.ph._crit_edge:                                ; preds = %.lr.ph, %7
  %.1 = phi i32 [ %spec.select, %7 ], [ %.068, %.lr.ph ]
  %12 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #1
  %13 = add i64 %12, -1
  %14 = icmp ugt i64 %13, %6
  br i1 %14, label %.lr.ph, label %._crit_edge, !llvm.loop !8
}

; 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,GVNPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass