; LLVM IR from wrnlb666/yet-another-string-library-in-c :: yasli (str_substr)

; 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_t = type { i64, i64, [1 x i8] }

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: inlinehint nounwind uwtable
declare hidden zeroext i1 @str_resize(ptr noundef, i64 noundef) #1

; Function Attrs: nounwind
declare ptr @strncpy(ptr noundef, ptr noundef, i64 noundef) #2

; Function Attrs: nounwind uwtable
define dso_local ptr @str_substr(ptr noundef %0, i64 noundef %1, i64 noundef %2) #3 {
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i64, align 8
  %7 = alloca i64, align 8
  %8 = alloca ptr, align 8
  %9 = alloca i32, align 4
  store ptr %0, ptr %5, align 8, !tbaa !5
  store i64 %1, ptr %6, align 8, !tbaa !9
  store i64 %2, ptr %7, align 8, !tbaa !9
  %10 = load i64, ptr %6, align 8, !tbaa !9
  %11 = load i64, ptr %7, align 8, !tbaa !9
  %12 = add i64 %10, %11
  %13 = load ptr, ptr %5, align 8, !tbaa !5
  %14 = getelementptr inbounds %struct.string_t, ptr %13, i32 0, i32 0
  %15 = load i64, ptr %14, align 8, !tbaa !11
  %16 = icmp ugt i64 %12, %15
  br i1 %16, label %17, label %18

17:                                               ; preds = %3
  store ptr null, ptr %4, align 8
  br label %41

18:                                               ; preds = %3
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #4
  store ptr null, ptr %8, align 8, !tbaa !5
  %19 = load i64, ptr %7, align 8, !tbaa !9
  %20 = call zeroext i1 @str_resize(ptr noundef %8, i64 noundef %19)
  br i1 %20, label %21, label %39

21:                                               ; preds = %18
  %22 = load ptr, ptr %8, align 8, !tbaa !5
  %23 = getelementptr inbounds %struct.string_t, ptr %22, i32 0, i32 2
  %24 = getelementptr inbounds [1 x i8], ptr %23, i64 0, i64 0
  %25 = load ptr, ptr %5, align 8, !tbaa !5
  %26 = getelementptr inbounds %struct.string_t, ptr %25, i32 0, i32 2
  %27 = getelementptr inbounds [1 x i8], ptr %26, i64 0, i64 0
  %28 = load i64, ptr %6, align 8, !tbaa !9
  %29 = getelementptr inbounds i8, ptr %27, i64 %28
  %30 = load i64, ptr %7, align 8, !tbaa !9
  %31 = call ptr @strncpy(ptr noundef %24, ptr noundef %29, i64 noundef %30) #4
  %32 = load ptr, ptr %8, align 8, !tbaa !5
  %33 = getelementptr inbounds %struct.string_t, ptr %32, i32 0, i32 2
  %34 = load ptr, ptr %8, align 8, !tbaa !5
  %35 = getelementptr inbounds %struct.string_t, ptr %34, i32 0, i32 0
  %36 = load i64, ptr %35, align 8, !tbaa !11
  %37 = getelementptr inbounds [1 x i8], ptr %33, i64 0, i64 %36
  store i8 0, ptr %37, align 1, !tbaa !13
  %38 = load ptr, ptr %8, align 8, !tbaa !5
  store ptr %38, ptr %4, align 8
  store i32 1, ptr %9, align 4
  br label %40

39:                                               ; preds = %18
  store ptr null, ptr %4, align 8
  store i32 1, ptr %9, align 4
  br label %40

40:                                               ; preds = %39, %21
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #4
  br label %41

41:                                               ; preds = %40, %17
  %42 = load ptr, ptr %4, align 8
  ret ptr %42
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { inlinehint 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 = { 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 #3 = { 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/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"long", !7, i64 0}
!11 = !{!12, !10, i64 0}
!12 = !{!"string_t", !10, i64 0, !10, i64 8, !7, i64 16}
!13 = !{!7, !7, i64 0}


; 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 nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: inlinehint nounwind uwtable
declare hidden zeroext i1 @str_resize(ptr noundef, i64 noundef) local_unnamed_addr #1

; Function Attrs: mustprogress nofree nounwind willreturn memory(argmem: readwrite)
declare ptr @strncpy(ptr noalias noundef returned writeonly, ptr noalias nocapture noundef readonly, i64 noundef) local_unnamed_addr #2

; Function Attrs: nounwind uwtable
define dso_local ptr @str_substr(ptr nocapture noundef readonly %0, i64 noundef %1, i64 noundef %2) local_unnamed_addr #3 {
  %4 = alloca ptr, align 8
  %5 = add i64 %2, %1
  %6 = load i64, ptr %0, align 8, !tbaa !5
  %7 = icmp ugt i64 %5, %6
  br i1 %7, label %20, label %8

8:                                                ; preds = %3
  call void @llvm.lifetime.start.p0(i64 8, ptr nonnull %4) #4
  store ptr null, ptr %4, align 8, !tbaa !10
  %9 = call zeroext i1 @str_resize(ptr noundef nonnull %4, i64 noundef %2)
  br i1 %9, label %10, label %19

10:                                               ; preds = %8
  %11 = load ptr, ptr %4, align 8, !tbaa !10
  %12 = getelementptr inbounds i8, ptr %11, i64 16
  %13 = getelementptr inbounds i8, ptr %0, i64 16
  %14 = getelementptr inbounds i8, ptr %13, i64 %1
  %15 = call ptr @strncpy(ptr noundef nonnull %12, ptr noundef nonnull %14, i64 noundef %2) #4
  %16 = load i64, ptr %11, align 8, !tbaa !5
  %17 = getelementptr inbounds [1 x i8], ptr %12, i64 0, i64 %16
  store i8 0, ptr %17, align 1, !tbaa !12
  %18 = load ptr, ptr %4, align 8, !tbaa !10
  br label %19

19:                                               ; preds = %8, %10
  %.0 = phi ptr [ %18, %10 ], [ null, %8 ]
  call void @llvm.lifetime.end.p0(i64 8, ptr nonnull %4) #4
  br label %20

20:                                               ; preds = %3, %19
  %.1 = phi ptr [ %.0, %19 ], [ null, %3 ]
  ret ptr %.1
}

attributes #0 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { inlinehint 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 nofree nounwind willreturn memory(argmem: readwrite) "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 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, !7, i64 0}
!6 = !{!"string_t", !7, i64 0, !7, i64 8, !8, i64 16}
!7 = !{!"long", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!11, !11, i64 0}
!11 = !{!"any pointer", !8, i64 0}
!12 = !{!8, !8, i64 0}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass