; LLVM IR from MostafaTwfiq/C-DataStructures-And-Algorithms :: DataStructure/Strings/Sources (String)

; 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"

%struct.String = type { ptr, i32, i32 }

@stderr = external global ptr, align 8
@.str = external hidden unnamed_addr constant [42 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [22 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [7 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [31 x i8], align 1
@.str.12 = external hidden unnamed_addr constant [23 x i8], align 1

; Function Attrs: nounwind
declare i32 @fprintf(ptr noundef, ptr noundef, ...) #0

; Function Attrs: noreturn nounwind
declare void @exit(i32 noundef) #1

; Function Attrs: nounwind uwtable
declare dso_local void @stringAppendChar(ptr noundef, i8 noundef signext) #2

; Function Attrs: nounwind uwtable
define dso_local void @stringChangeStringC(ptr noundef %0, ptr noundef %1) #2 {
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  store ptr %0, ptr %3, align 8, !tbaa !5
  store ptr %1, ptr %4, align 8, !tbaa !5
  %5 = load ptr, ptr %3, align 8, !tbaa !5
  %6 = icmp eq ptr %5, null
  br i1 %6, label %7, label %10

7:                                                ; preds = %2
  %8 = load ptr, ptr @stderr, align 8, !tbaa !5
  %9 = call i32 (ptr, ptr, ...) @fprintf(ptr noundef %8, ptr noundef @.str.6, ptr noundef @.str.4, ptr noundef @.str.2) #3
  call void @exit(i32 noundef -83386157) #4
  unreachable

10:                                               ; preds = %2
  %11 = load ptr, ptr %4, align 8, !tbaa !5
  %12 = icmp eq ptr %11, null
  br i1 %12, label %13, label %16

13:                                               ; preds = %10
  %14 = load ptr, ptr @stderr, align 8, !tbaa !5
  %15 = call i32 (ptr, ptr, ...) @fprintf(ptr noundef %14, ptr noundef @.str, ptr noundef @.str.12, ptr noundef @.str.2) #3
  call void @exit(i32 noundef -83384987) #4
  unreachable

16:                                               ; preds = %10
  br label %17

17:                                               ; preds = %16
  %18 = load ptr, ptr %3, align 8, !tbaa !5
  %19 = getelementptr inbounds %struct.String, ptr %18, i32 0, i32 1
  store i32 0, ptr %19, align 8, !tbaa !9
  %20 = load ptr, ptr %3, align 8, !tbaa !5
  %21 = getelementptr inbounds %struct.String, ptr %20, i32 0, i32 0
  %22 = load ptr, ptr %21, align 8, !tbaa !12
  %23 = load ptr, ptr %3, align 8, !tbaa !5
  %24 = getelementptr inbounds %struct.String, ptr %23, i32 0, i32 1
  %25 = load i32, ptr %24, align 8, !tbaa !9
  %26 = sext i32 %25 to i64
  %27 = getelementptr inbounds i8, ptr %22, i64 %26
  store i8 0, ptr %27, align 1, !tbaa !13
  br label %28

28:                                               ; preds = %33, %17
  %29 = load ptr, ptr %4, align 8, !tbaa !5
  %30 = load i8, ptr %29, align 1, !tbaa !13
  %31 = sext i8 %30 to i32
  %32 = icmp ne i32 %31, 0
  br i1 %32, label %33, label %38

33:                                               ; preds = %28
  %34 = load ptr, ptr %3, align 8, !tbaa !5
  %35 = load ptr, ptr %4, align 8, !tbaa !5
  %36 = getelementptr inbounds i8, ptr %35, i32 1
  store ptr %36, ptr %4, align 8, !tbaa !5
  %37 = load i8, ptr %35, align 1, !tbaa !13
  call void @stringAppendChar(ptr noundef %34, i8 noundef signext %37)
  br label %28, !llvm.loop !14

38:                                               ; preds = %28
  ret void
}

attributes #0 = { nounwind "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 = { noreturn nounwind "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 = { 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 }
attributes #4 = { noreturn 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/C++ TBAA"}
!9 = !{!10, !11, i64 8}
!10 = !{!"String", !6, i64 0, !11, i64 8, !11, i64 12}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !6, i64 0}
!13 = !{!7, !7, i64 0}
!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"

@stderr = external local_unnamed_addr global ptr, align 8
@.str = external hidden unnamed_addr constant [42 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [22 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [7 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [31 x i8], align 1
@.str.12 = external hidden unnamed_addr constant [23 x i8], align 1

; Function Attrs: nofree nounwind
declare noundef i32 @fprintf(ptr nocapture noundef, ptr nocapture noundef readonly, ...) local_unnamed_addr #0

; Function Attrs: noreturn nounwind
declare void @exit(i32 noundef) local_unnamed_addr #1

; Function Attrs: nounwind uwtable
declare dso_local void @stringAppendChar(ptr noundef, i8 noundef signext) local_unnamed_addr #2

; Function Attrs: nounwind uwtable
define dso_local void @stringChangeStringC(ptr noundef %0, ptr noundef readonly %1) local_unnamed_addr #2 {
  %3 = icmp eq ptr %0, null
  br i1 %3, label %4, label %7

4:                                                ; preds = %2
  %5 = load ptr, ptr @stderr, align 8, !tbaa !5
  %6 = tail call i32 (ptr, ptr, ...) @fprintf(ptr noundef %5, ptr noundef nonnull @.str.6, ptr noundef nonnull @.str.4, ptr noundef nonnull @.str.2) #3
  tail call void @exit(i32 noundef -83386157) #4
  unreachable

7:                                                ; preds = %2
  %8 = icmp eq ptr %1, null
  br i1 %8, label %9, label %12

9:                                                ; preds = %7
  %10 = load ptr, ptr @stderr, align 8, !tbaa !5
  %11 = tail call i32 (ptr, ptr, ...) @fprintf(ptr noundef %10, ptr noundef nonnull @.str, ptr noundef nonnull @.str.12, ptr noundef nonnull @.str.2) #3
  tail call void @exit(i32 noundef -83384987) #4
  unreachable

12:                                               ; preds = %7
  %13 = getelementptr inbounds i8, ptr %0, i64 8
  store i32 0, ptr %13, align 8, !tbaa !9
  %14 = load ptr, ptr %0, align 8, !tbaa !12
  store i8 0, ptr %14, align 1, !tbaa !13
  %15 = load i8, ptr %1, align 1, !tbaa !13
  %.not10 = icmp eq i8 %15, 0
  br i1 %.not10, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %12, %.lr.ph
  %16 = phi i8 [ %18, %.lr.ph ], [ %15, %12 ]
  %.011 = phi ptr [ %17, %.lr.ph ], [ %1, %12 ]
  %17 = getelementptr inbounds i8, ptr %.011, i64 1
  tail call void @stringAppendChar(ptr noundef nonnull %0, i8 noundef signext %16)
  %18 = load i8, ptr %17, align 1, !tbaa !13
  %.not = icmp eq i8 %18, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !14

._crit_edge:                                      ; preds = %.lr.ph, %12
  ret void
}

attributes #0 = { nofree nounwind "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 = { noreturn nounwind "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 = { 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 = { cold nounwind }
attributes #4 = { noreturn 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/C++ TBAA"}
!9 = !{!10, !11, i64 8}
!10 = !{!"String", !6, i64 0, !11, i64 8, !11, i64 12}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !6, i64 0}
!13 = !{!7, !7, i64 0}
!14 = distinct !{!14, !15}
!15 = !{!"llvm.loop.mustprogress"}


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