; LLVM IR from DimitrisJim/leetcode_solutions :: C/Algorithms (559)

; 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.Node = type { i32, i32, ptr }

; Function Attrs: nounwind uwtable
define dso_local i32 @depth(ptr noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  %7 = load ptr, ptr %3, align 8, !tbaa !5
  %8 = getelementptr inbounds %struct.Node, ptr %7, i32 0, i32 1
  %9 = load i32, ptr %8, align 4, !tbaa !9
  %10 = icmp eq i32 %9, 0
  br i1 %10, label %11, label %12

11:                                               ; preds = %1
  store i32 1, ptr %2, align 4
  br label %41

12:                                               ; preds = %1
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #2
  store i32 0, ptr %4, align 4, !tbaa !12
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  store i32 0, ptr %5, align 4, !tbaa !12
  br label %13

13:                                               ; preds = %35, %12
  %14 = load i32, ptr %5, align 4, !tbaa !12
  %15 = load ptr, ptr %3, align 8, !tbaa !5
  %16 = getelementptr inbounds %struct.Node, ptr %15, i32 0, i32 1
  %17 = load i32, ptr %16, align 4, !tbaa !9
  %18 = icmp slt i32 %14, %17
  br i1 %18, label %20, label %19

19:                                               ; preds = %13
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  br label %38

20:                                               ; preds = %13
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  %21 = load ptr, ptr %3, align 8, !tbaa !5
  %22 = getelementptr inbounds %struct.Node, ptr %21, i32 0, i32 2
  %23 = load ptr, ptr %22, align 8, !tbaa !13
  %24 = load i32, ptr %5, align 4, !tbaa !12
  %25 = sext i32 %24 to i64
  %26 = getelementptr inbounds ptr, ptr %23, i64 %25
  %27 = load ptr, ptr %26, align 8, !tbaa !5
  %28 = call i32 @depth(ptr noundef %27)
  store i32 %28, ptr %6, align 4, !tbaa !12
  %29 = load i32, ptr %6, align 4, !tbaa !12
  %30 = load i32, ptr %4, align 4, !tbaa !12
  %31 = icmp sgt i32 %29, %30
  br i1 %31, label %32, label %34

32:                                               ; preds = %20
  %33 = load i32, ptr %6, align 4, !tbaa !12
  store i32 %33, ptr %4, align 4, !tbaa !12
  br label %34

34:                                               ; preds = %32, %20
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  br label %35

35:                                               ; preds = %34
  %36 = load i32, ptr %5, align 4, !tbaa !12
  %37 = add nsw i32 %36, 1
  store i32 %37, ptr %5, align 4, !tbaa !12
  br label %13, !llvm.loop !14

38:                                               ; preds = %19
  %39 = load i32, ptr %4, align 4, !tbaa !12
  %40 = add nsw i32 %39, 1
  store i32 %40, ptr %2, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #2
  br label %41

41:                                               ; preds = %38, %11
  %42 = load i32, ptr %2, align 4
  ret i32 %42
}

; 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

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 = { 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 4}
!10 = !{!"Node", !11, i64 0, !11, i64 4, !6, i64 8}
!11 = !{!"int", !7, i64 0}
!12 = !{!11, !11, i64 0}
!13 = !{!10, !6, i64 8}
!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"

; Function Attrs: nofree nosync nounwind memory(read, inaccessiblemem: none) uwtable
define dso_local i32 @depth(ptr nocapture noundef readonly %0) local_unnamed_addr #0 {
  %2 = getelementptr inbounds i8, ptr %0, i64 4
  %3 = load i32, ptr %2, align 4, !tbaa !5
  %4 = icmp sgt i32 %3, 0
  br i1 %4, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %1
  %5 = getelementptr inbounds i8, ptr %0, i64 8
  %6 = load ptr, ptr %5, align 8, !tbaa !11
  %wide.trip.count = zext nneg i32 %3 to i64
  br label %8

._crit_edge.loopexit:                             ; preds = %8
  %7 = add nuw nsw i32 %spec.select, 1
  br label %._crit_edge

8:                                                ; preds = %.lr.ph, %8
  %indvars.iv = phi i64 [ 0, %.lr.ph ], [ %indvars.iv.next, %8 ]
  %.01113 = phi i32 [ 0, %.lr.ph ], [ %spec.select, %8 ]
  %9 = getelementptr inbounds ptr, ptr %6, i64 %indvars.iv
  %10 = load ptr, ptr %9, align 8, !tbaa !12
  %11 = tail call i32 @depth(ptr noundef %10)
  %spec.select = tail call i32 @llvm.smax.i32(i32 %11, i32 %.01113)
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %exitcond.not = icmp eq i64 %indvars.iv.next, %wide.trip.count
  br i1 %exitcond.not, label %._crit_edge.loopexit, label %8, !llvm.loop !13

._crit_edge:                                      ; preds = %._crit_edge.loopexit, %1
  %.0 = phi i32 [ 1, %1 ], [ %7, %._crit_edge.loopexit ]
  ret i32 %.0
}

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.smax.i32(i32, i32) #1

attributes #0 = { nofree nosync nounwind memory(read, inaccessiblemem: none) 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 speculatable willreturn memory(none) }

!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 4}
!6 = !{!"Node", !7, i64 0, !7, i64 4, !10, i64 8}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = !{!6, !10, i64 8}
!12 = !{!10, !10, i64 0}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}


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