; LLVM IR from kaynewbie/algorithm :: algorithm/LeetCode/Easy (maximum-depth-of-binary-tree)

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

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

10:                                               ; preds = %2
  %11 = load i32, ptr %5, align 4, !tbaa !9
  store i32 %11, ptr %3, align 4
  br label %34

12:                                               ; preds = %2
  %13 = load i32, ptr %5, align 4, !tbaa !9
  %14 = add nsw i32 %13, 1
  store i32 %14, ptr %5, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  %15 = load ptr, ptr %4, align 8, !tbaa !5
  %16 = getelementptr inbounds %struct.TreeNode, ptr %15, i32 0, i32 1
  %17 = load ptr, ptr %16, align 8, !tbaa !11
  %18 = load i32, ptr %5, align 4, !tbaa !9
  %19 = call i32 @depthInTree(ptr noundef %17, i32 noundef %18)
  store i32 %19, ptr %6, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  %20 = load ptr, ptr %4, align 8, !tbaa !5
  %21 = getelementptr inbounds %struct.TreeNode, ptr %20, i32 0, i32 2
  %22 = load ptr, ptr %21, align 8, !tbaa !13
  %23 = load i32, ptr %5, align 4, !tbaa !9
  %24 = call i32 @depthInTree(ptr noundef %22, i32 noundef %23)
  store i32 %24, ptr %7, align 4, !tbaa !9
  %25 = load i32, ptr %6, align 4, !tbaa !9
  %26 = load i32, ptr %7, align 4, !tbaa !9
  %27 = icmp sgt i32 %25, %26
  br i1 %27, label %28, label %30

28:                                               ; preds = %12
  %29 = load i32, ptr %6, align 4, !tbaa !9
  br label %32

30:                                               ; preds = %12
  %31 = load i32, ptr %7, align 4, !tbaa !9
  br label %32

32:                                               ; preds = %30, %28
  %33 = phi i32 [ %29, %28 ], [ %31, %30 ]
  store i32 %33, ptr %3, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  br label %34

34:                                               ; preds = %32, %10
  %35 = load i32, ptr %3, align 4
  ret i32 %35
}

; 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, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{!12, !6, i64 8}
!12 = !{!"TreeNode", !10, i64 0, !6, i64 8, !6, i64 16}
!13 = !{!12, !6, i64 16}


; 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 @depthInTree(ptr noundef readonly %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = icmp eq ptr %0, null
  br i1 %3, label %tailrecurse._crit_edge, label %tailrecurse

tailrecurse:                                      ; preds = %2, %tailrecurse
  %.tr1215 = phi i32 [ %4, %tailrecurse ], [ %1, %2 ]
  %.tr14 = phi ptr [ %9, %tailrecurse ], [ %0, %2 ]
  %accumulator.tr13 = phi i32 [ %10, %tailrecurse ], [ -2147483648, %2 ]
  %4 = add nsw i32 %.tr1215, 1
  %5 = getelementptr inbounds i8, ptr %.tr14, i64 8
  %6 = load ptr, ptr %5, align 8, !tbaa !5
  %7 = tail call i32 @depthInTree(ptr noundef %6, i32 noundef %4)
  %8 = getelementptr inbounds i8, ptr %.tr14, i64 16
  %9 = load ptr, ptr %8, align 8, !tbaa !11
  %10 = tail call i32 @llvm.smax.i32(i32 %7, i32 %accumulator.tr13)
  %11 = icmp eq ptr %9, null
  br i1 %11, label %tailrecurse._crit_edge, label %tailrecurse

tailrecurse._crit_edge:                           ; preds = %tailrecurse, %2
  %accumulator.tr.lcssa = phi i32 [ -2147483648, %2 ], [ %10, %tailrecurse ]
  %.tr12.lcssa = phi i32 [ %1, %2 ], [ %4, %tailrecurse ]
  %accumulator.ret.tr = tail call i32 @llvm.smax.i32(i32 %.tr12.lcssa, i32 %accumulator.tr.lcssa)
  ret i32 %accumulator.ret.tr
}

; 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, !10, i64 8}
!6 = !{!"TreeNode", !7, i64 0, !10, i64 8, !10, i64 16}
!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 16}


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