; LLVM IR from ritikbanger/Hacktoberfest2022-DSA :: 10. Linked List/c lang/CircularDoublyLinkedList (Traversing)

; 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"

@.str.5 = external hidden unnamed_addr constant [21 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [22 x i8], align 1
@.str.7 = external hidden unnamed_addr constant [47 x i8], align 1
@.str.8 = external hidden unnamed_addr constant [16 x i8], align 1
@.str.9 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.10 = external hidden unnamed_addr constant [16 x i8], align 1
@.str.11 = external hidden unnamed_addr constant [2 x i8], align 1
@.str.12 = external hidden unnamed_addr constant [3 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local void @add(i32 noundef) #0

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

; Function Attrs: nounwind uwtable
declare dso_local void @display() #0

declare i32 @printf(ptr noundef, ...) #2

; Function Attrs: nounwind uwtable
declare dso_local void @revDisplay() #0

; Function Attrs: nounwind uwtable
define dso_local i32 @main() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  %4 = call i32 (ptr, ...) @printf(ptr noundef @.str.5)
  %5 = call i32 (ptr, ...) @printf(ptr noundef @.str.6)
  %6 = call i32 (ptr, ...) @printf(ptr noundef @.str.7)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #3
  br label %7

7:                                                ; preds = %35, %0
  br label %8

8:                                                ; preds = %7
  %9 = call i32 (ptr, ...) @printf(ptr noundef @.str.8)
  %10 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.9, ptr noundef %2)
  %11 = load i32, ptr %2, align 4, !tbaa !5
  %12 = icmp eq i32 %11, 1
  br i1 %12, label %13, label %18

13:                                               ; preds = %8
  %14 = call i32 (ptr, ...) @printf(ptr noundef @.str.10)
  %15 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.9, ptr noundef %3)
  %16 = call i32 (ptr, ...) @printf(ptr noundef @.str.11)
  %17 = load i32, ptr %3, align 4, !tbaa !5
  call void @add(i32 noundef %17)
  br label %35

18:                                               ; preds = %8
  %19 = load i32, ptr %2, align 4, !tbaa !5
  %20 = icmp eq i32 %19, 2
  br i1 %20, label %21, label %23

21:                                               ; preds = %18
  call void @display()
  %22 = call i32 (ptr, ...) @printf(ptr noundef @.str.12)
  br label %34

23:                                               ; preds = %18
  %24 = load i32, ptr %2, align 4, !tbaa !5
  %25 = icmp eq i32 %24, 3
  br i1 %25, label %26, label %28

26:                                               ; preds = %23
  call void @revDisplay()
  %27 = call i32 (ptr, ...) @printf(ptr noundef @.str.12)
  br label %33

28:                                               ; preds = %23
  %29 = load i32, ptr %2, align 4, !tbaa !5
  %30 = icmp eq i32 %29, 0
  br i1 %30, label %31, label %32

31:                                               ; preds = %28
  br label %36

32:                                               ; preds = %28
  br label %33

33:                                               ; preds = %32, %26
  br label %34

34:                                               ; preds = %33, %21
  br label %35

35:                                               ; preds = %34, %13
  br label %7

36:                                               ; preds = %31
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #3
  %37 = load i32, ptr %1, align 4
  ret i32 %37
}

declare i32 @__isoc99_scanf(ptr noundef, ...) #2

attributes #0 = { 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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { "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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}


; 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"

@.str.5 = external hidden unnamed_addr constant [21 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [22 x i8], align 1
@.str.7 = external hidden unnamed_addr constant [47 x i8], align 1
@.str.8 = external hidden unnamed_addr constant [16 x i8], align 1
@.str.9 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.10 = external hidden unnamed_addr constant [16 x i8], align 1
@.str.11 = external hidden unnamed_addr constant [2 x i8], align 1
@.str.12 = external hidden unnamed_addr constant [3 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local void @add(i32 noundef) local_unnamed_addr #0

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

; Function Attrs: nounwind uwtable
declare dso_local void @display() local_unnamed_addr #0

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

; Function Attrs: nounwind uwtable
declare dso_local void @revDisplay() local_unnamed_addr #0

; Function Attrs: nounwind uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.5)
  %4 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.6)
  %5 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.7)
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #3
  br label %6

6:                                                ; preds = %.backedge, %0
  %7 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.8)
  %8 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.9, ptr noundef nonnull %1)
  %9 = load i32, ptr %1, align 4, !tbaa !5
  switch i32 %9, label %.backedge [
    i32 1, label %10
    i32 2, label %15
    i32 3, label %17
    i32 0, label %19
  ]

.backedge:                                        ; preds = %6, %15, %17, %10
  br label %6

10:                                               ; preds = %6
  %11 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.10)
  %12 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.9, ptr noundef nonnull %2)
  %13 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.11)
  %14 = load i32, ptr %2, align 4, !tbaa !5
  call void @add(i32 noundef %14)
  br label %.backedge

15:                                               ; preds = %6
  call void @display()
  %16 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.12)
  br label %.backedge

17:                                               ; preds = %6
  call void @revDisplay()
  %18 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.12)
  br label %.backedge

19:                                               ; preds = %6
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #3
  ret i32 0
}

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

attributes #0 = { 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 = { 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 #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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}


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