; LLVM IR from bartobri/data-structures-c :: symbol-table/binary-search-tree-perfect-balancing (st)

; 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.STnode = type { ptr, ptr, ptr, i32 }
%struct.anon = type { i32, i32 }

@z = external hidden global ptr, align 8

; 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: nounwind uwtable
define dso_local ptr @STsearchR(ptr noundef %0, i32 noundef %1) #1 {
  %3 = alloca ptr, align 8
  %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
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  %8 = load ptr, ptr %4, align 8, !tbaa !5
  %9 = load ptr, ptr @z, align 8, !tbaa !5
  %10 = icmp eq ptr %8, %9
  br i1 %10, label %11, label %12

11:                                               ; preds = %2
  store ptr null, ptr %3, align 8
  store i32 1, ptr %7, align 4
  br label %41

12:                                               ; preds = %2
  %13 = load ptr, ptr %4, align 8, !tbaa !5
  %14 = getelementptr inbounds %struct.STnode, ptr %13, i32 0, i32 0
  %15 = load ptr, ptr %14, align 8, !tbaa !11
  %16 = getelementptr inbounds %struct.anon, ptr %15, i32 0, i32 0
  %17 = load i32, ptr %16, align 4, !tbaa !13
  store i32 %17, ptr %6, align 4, !tbaa !9
  %18 = load i32, ptr %5, align 4, !tbaa !9
  %19 = load i32, ptr %6, align 4, !tbaa !9
  %20 = icmp eq i32 %18, %19
  br i1 %20, label %21, label %25

21:                                               ; preds = %12
  %22 = load ptr, ptr %4, align 8, !tbaa !5
  %23 = getelementptr inbounds %struct.STnode, ptr %22, i32 0, i32 0
  %24 = load ptr, ptr %23, align 8, !tbaa !11
  store ptr %24, ptr %3, align 8
  store i32 1, ptr %7, align 4
  br label %41

25:                                               ; preds = %12
  %26 = load i32, ptr %5, align 4, !tbaa !9
  %27 = load i32, ptr %6, align 4, !tbaa !9
  %28 = icmp slt i32 %26, %27
  br i1 %28, label %29, label %35

29:                                               ; preds = %25
  %30 = load ptr, ptr %4, align 8, !tbaa !5
  %31 = getelementptr inbounds %struct.STnode, ptr %30, i32 0, i32 1
  %32 = load ptr, ptr %31, align 8, !tbaa !15
  %33 = load i32, ptr %5, align 4, !tbaa !9
  %34 = call ptr @STsearchR(ptr noundef %32, i32 noundef %33)
  store ptr %34, ptr %3, align 8
  store i32 1, ptr %7, align 4
  br label %41

35:                                               ; preds = %25
  %36 = load ptr, ptr %4, align 8, !tbaa !5
  %37 = getelementptr inbounds %struct.STnode, ptr %36, i32 0, i32 2
  %38 = load ptr, ptr %37, align 8, !tbaa !16
  %39 = load i32, ptr %5, align 4, !tbaa !9
  %40 = call ptr @STsearchR(ptr noundef %38, i32 noundef %39)
  store ptr %40, ptr %3, align 8
  store i32 1, ptr %7, align 4
  br label %41

41:                                               ; preds = %35, %29, %21, %11
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  %42 = load ptr, ptr %3, align 8
  ret ptr %42
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 }

!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 0}
!12 = !{!"STnode", !6, i64 0, !6, i64 8, !6, i64 16, !10, i64 24}
!13 = !{!14, !10, i64 0}
!14 = !{!"", !10, i64 0, !10, i64 4}
!15 = !{!12, !6, i64 8}
!16 = !{!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"

@z = external hidden local_unnamed_addr global ptr, align 8

; Function Attrs: nofree norecurse nosync nounwind memory(read, inaccessiblemem: none) uwtable
define dso_local noundef ptr @STsearchR(ptr noundef readonly %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = load ptr, ptr @z, align 8, !tbaa !5
  %4 = icmp eq ptr %3, %0
  br i1 %4, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %2, %tailrecurse.backedge
  %.tr15 = phi ptr [ %.tr.be, %tailrecurse.backedge ], [ %0, %2 ]
  %5 = load ptr, ptr %.tr15, align 8, !tbaa !9
  %6 = load i32, ptr %5, align 4, !tbaa !12
  %7 = icmp eq i32 %6, %1
  br i1 %7, label %._crit_edge, label %tailrecurse.backedge

tailrecurse.backedge:                             ; preds = %.lr.ph
  %8 = icmp sgt i32 %6, %1
  %spec.select = select i1 %8, i64 8, i64 16
  %9 = getelementptr inbounds i8, ptr %.tr15, i64 %spec.select
  %.tr.be = load ptr, ptr %9, align 8, !tbaa !5
  %10 = icmp eq ptr %3, %.tr.be
  br i1 %10, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %tailrecurse.backedge, %.lr.ph, %2
  %.0 = phi ptr [ null, %2 ], [ %5, %.lr.ph ], [ null, %tailrecurse.backedge ]
  ret ptr %.0
}

attributes #0 = { nofree norecurse 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" }

!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, !6, i64 0}
!10 = !{!"STnode", !6, i64 0, !6, i64 8, !6, i64 16, !11, i64 24}
!11 = !{!"int", !7, i64 0}
!12 = !{!13, !11, i64 0}
!13 = !{!"", !11, i64 0, !11, i64 4}


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