; LLVM IR from kaynewbie/algorithm :: algorithm/CodingInterviews (question-26)

; 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 zeroext i1 @isSubtree(ptr noundef %0, ptr noundef %1) #0 {
  %3 = alloca i1, align 1
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  store ptr %0, ptr %4, align 8, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !5
  %6 = load ptr, ptr %4, align 8, !tbaa !5
  %7 = icmp eq ptr %6, null
  br i1 %7, label %11, label %8

8:                                                ; preds = %2
  %9 = load ptr, ptr %5, align 8, !tbaa !5
  %10 = icmp eq ptr %9, null
  br i1 %10, label %11, label %12

11:                                               ; preds = %8, %2
  store i1 false, ptr %3, align 1
  br label %40

12:                                               ; preds = %8
  %13 = load ptr, ptr %4, align 8, !tbaa !5
  %14 = getelementptr inbounds %struct.TreeNode, ptr %13, i32 0, i32 0
  %15 = load i32, ptr %14, align 8, !tbaa !9
  %16 = load ptr, ptr %5, align 8, !tbaa !5
  %17 = getelementptr inbounds %struct.TreeNode, ptr %16, i32 0, i32 0
  %18 = load i32, ptr %17, align 8, !tbaa !9
  %19 = icmp eq i32 %15, %18
  br i1 %19, label %20, label %26

20:                                               ; preds = %12
  %21 = load ptr, ptr %4, align 8, !tbaa !5
  %22 = load ptr, ptr %5, align 8, !tbaa !5
  %23 = call zeroext i1 @isSubtreeCore(ptr noundef %21, ptr noundef %22)
  br i1 %23, label %24, label %25

24:                                               ; preds = %20
  store i1 true, ptr %3, align 1
  br label %40

25:                                               ; preds = %20
  br label %26

26:                                               ; preds = %25, %12
  %27 = load ptr, ptr %4, align 8, !tbaa !5
  %28 = getelementptr inbounds %struct.TreeNode, ptr %27, i32 0, i32 1
  %29 = load ptr, ptr %28, align 8, !tbaa !12
  %30 = load ptr, ptr %5, align 8, !tbaa !5
  %31 = call zeroext i1 @isSubtree(ptr noundef %29, ptr noundef %30)
  br i1 %31, label %38, label %32

32:                                               ; preds = %26
  %33 = load ptr, ptr %4, align 8, !tbaa !5
  %34 = getelementptr inbounds %struct.TreeNode, ptr %33, i32 0, i32 2
  %35 = load ptr, ptr %34, align 8, !tbaa !13
  %36 = load ptr, ptr %5, align 8, !tbaa !5
  %37 = call zeroext i1 @isSubtree(ptr noundef %35, ptr noundef %36)
  br label %38

38:                                               ; preds = %32, %26
  %39 = phi i1 [ true, %26 ], [ %37, %32 ]
  store i1 %39, ptr %3, align 1
  br label %40

40:                                               ; preds = %38, %24, %11
  %41 = load i1, ptr %3, align 1
  ret i1 %41
}

; Function Attrs: nounwind uwtable
declare dso_local zeroext i1 @isSubtreeCore(ptr noundef, ptr noundef) #0

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" }

!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 0}
!10 = !{!"TreeNode", !11, i64 0, !6, i64 8, !6, i64 16}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !6, i64 8}
!13 = !{!10, !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: nounwind uwtable
define dso_local noundef zeroext i1 @isSubtree(ptr noundef %0, ptr noundef %1) local_unnamed_addr #0 {
  %3 = icmp eq ptr %1, null
  %4 = icmp eq ptr %0, null
  %or.cond15 = or i1 %3, %4
  br i1 %or.cond15, label %._crit_edge, label %.lr.ph.split

.lr.ph.split:                                     ; preds = %2, %tailrecurse
  %.tr16 = phi ptr [ %15, %tailrecurse ], [ %0, %2 ]
  %5 = load i32, ptr %.tr16, align 8, !tbaa !5
  %6 = load i32, ptr %1, align 8, !tbaa !5
  %7 = icmp eq i32 %5, %6
  br i1 %7, label %8, label %10

8:                                                ; preds = %.lr.ph.split
  %9 = tail call zeroext i1 @isSubtreeCore(ptr noundef nonnull %.tr16, ptr noundef nonnull %1)
  br i1 %9, label %._crit_edge, label %10

10:                                               ; preds = %8, %.lr.ph.split
  %11 = getelementptr inbounds i8, ptr %.tr16, i64 8
  %12 = load ptr, ptr %11, align 8, !tbaa !11
  %13 = tail call zeroext i1 @isSubtree(ptr noundef %12, ptr noundef nonnull %1)
  br i1 %13, label %._crit_edge, label %tailrecurse

tailrecurse:                                      ; preds = %10
  %14 = getelementptr inbounds i8, ptr %.tr16, i64 16
  %15 = load ptr, ptr %14, align 8, !tbaa !12
  %16 = icmp eq ptr %15, null
  br i1 %16, label %._crit_edge, label %.lr.ph.split

._crit_edge:                                      ; preds = %tailrecurse, %8, %10, %2
  %.0 = phi i1 [ false, %2 ], [ true, %10 ], [ true, %8 ], [ false, %tailrecurse ]
  ret i1 %.0
}

; Function Attrs: nounwind uwtable
declare dso_local zeroext i1 @isSubtreeCore(ptr noundef, ptr noundef) local_unnamed_addr #0

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" }

!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 = !{!"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 8}
!12 = !{!6, !10, i64 16}


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