; LLVM IR from UtkarshPathrabe/Competitive-Coding :: Cracking the Coding Interview/Chapter 01 (Question01)

; 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 @_Z9hasUniqueNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE(ptr noundef %0) #0 {
  %2 = alloca i1, align 1
  %3 = alloca ptr, align 8
  %4 = alloca [256 x i8], align 16
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 256, ptr %4) #4
  call void @llvm.memset.p0.i64(ptr align 16 %4, i8 0, i64 256, i1 false)
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #4
  store i32 0, ptr %5, align 4, !tbaa !9
  br label %8

8:                                                ; preds = %33, %1
  %9 = load i32, ptr %5, align 4, !tbaa !9
  %10 = sext i32 %9 to i64
  %11 = call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #4
  %12 = icmp ult i64 %10, %11
  br i1 %12, label %14, label %13

13:                                               ; preds = %8
  store i32 2, ptr %6, align 4
  br label %36

14:                                               ; preds = %8
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #4
  %15 = load i32, ptr %5, align 4, !tbaa !9
  %16 = sext i32 %15 to i64
  %17 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %16)
  %18 = load i8, ptr %17, align 1, !tbaa !11
  %19 = sext i8 %18 to i32
  store i32 %19, ptr %7, align 4, !tbaa !9
  %20 = load i32, ptr %7, align 4, !tbaa !9
  %21 = sext i32 %20 to i64
  %22 = getelementptr inbounds [256 x i8], ptr %4, i64 0, i64 %21
  %23 = load i8, ptr %22, align 1, !tbaa !12, !range !14, !noundef !15
  %24 = trunc i8 %23 to i1
  br i1 %24, label %25, label %26

25:                                               ; preds = %14
  store i1 false, ptr %2, align 1
  store i32 1, ptr %6, align 4
  br label %30

26:                                               ; preds = %14
  %27 = load i32, ptr %7, align 4, !tbaa !9
  %28 = sext i32 %27 to i64
  %29 = getelementptr inbounds [256 x i8], ptr %4, i64 0, i64 %28
  store i8 1, ptr %29, align 1, !tbaa !12
  store i32 0, ptr %6, align 4
  br label %30

30:                                               ; preds = %26, %25
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #4
  %31 = load i32, ptr %6, align 4
  switch i32 %31, label %36 [
    i32 0, label %32
  ]

32:                                               ; preds = %30
  br label %33

33:                                               ; preds = %32
  %34 = load i32, ptr %5, align 4, !tbaa !9
  %35 = add nsw i32 %34, 1
  store i32 %35, ptr %5, align 4, !tbaa !9
  br label %8, !llvm.loop !16

36:                                               ; preds = %30, %13
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #4
  %37 = load i32, ptr %6, align 4
  switch i32 %37, label %39 [
    i32 2, label %38
  ]

38:                                               ; preds = %36
  store i1 true, ptr %2, align 1
  store i32 1, ptr %6, align 4
  br label %39

39:                                               ; preds = %38, %36
  call void @llvm.lifetime.end.p0(i64 256, ptr %4) #4
  %40 = load i1, ptr %2, align 1
  ret i1 %40
}

; 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 nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #2

; Function Attrs: mustprogress nounwind uwtable
declare noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32)) #3 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) #3 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 = { nocallback nofree nounwind willreturn memory(argmem: write) }
attributes #3 = { 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 #4 = { 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 = !{!13, !13, i64 0}
!13 = !{!"bool", !7, i64 0}
!14 = !{i8 0, i8 2}
!15 = !{}
!16 = distinct !{!16, !17}
!17 = !{!"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 @_Z9hasUniqueNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE(ptr noundef nonnull %0) local_unnamed_addr #0 {
  %2 = alloca [256 x i8], align 16
  call void @llvm.lifetime.start.p0(i64 256, ptr nonnull %2) #3
  call void @llvm.memset.p0.i64(ptr noundef nonnull align 16 dereferenceable(256) %2, i8 0, i64 256, i1 false)
  %3 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #3
  %.not13 = icmp eq i64 %3, 0
  br i1 %.not13, label %.critedge, label %.lr.ph

.lr.ph:                                           ; preds = %1, %10
  %indvars.iv = phi i64 [ %indvars.iv.next, %10 ], [ 0, %1 ]
  %4 = 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)
  %5 = load i8, ptr %4, align 1, !tbaa !5
  %6 = sext i8 %5 to i64
  %7 = getelementptr inbounds [256 x i8], ptr %2, i64 0, i64 %6
  %8 = load i8, ptr %7, align 1, !tbaa !8, !range !10, !noundef !11
  %9 = trunc nuw i8 %8 to i1
  br i1 %9, label %.critedge.loopexit, label %10

10:                                               ; preds = %.lr.ph
  store i8 1, ptr %7, align 1, !tbaa !8
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %11 = tail call noundef i64 @_ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE6lengthEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #3
  %.not.not = icmp ugt i64 %11, %indvars.iv.next
  br i1 %.not.not, label %.lr.ph, label %.critedge.loopexit, !llvm.loop !12

.critedge.loopexit:                               ; preds = %10, %.lr.ph
  %.not.lcssa.ph = xor i1 %9, true
  br label %.critedge

.critedge:                                        ; preds = %.critedge.loopexit, %1
  %.not.lcssa = phi i1 [ true, %1 ], [ %.not.lcssa.ph, %.critedge.loopexit ]
  call void @llvm.lifetime.end.p0(i64 256, ptr nonnull %2) #3
  ret i1 %.not.lcssa
}

; 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 nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #2

; 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

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

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 nocallback nofree nounwind willreturn memory(argmem: write) }
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 = !{!9, !9, i64 0}
!9 = !{!"bool", !6, i64 0}
!10 = !{i8 0, i8 2}
!11 = !{}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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