; LLVM IR from ippeb/ACM-ICPC :: data_structure/binary_search_tree/binary_search_tree.ll (Z15unlink_smallestP4node)

; 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"

%class.node = type { i32, ptr, ptr }

; Function Attrs: mustprogress uwtable
define dso_local noundef ptr @_Z15unlink_smallestP4node(ptr noundef %0) #0 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  store ptr %0, ptr %3, align 8, !tbaa !5
  %4 = load ptr, ptr %3, align 8, !tbaa !5
  %5 = getelementptr inbounds %class.node, ptr %4, i32 0, i32 2
  %6 = load ptr, ptr %5, align 8, !tbaa !9
  %7 = icmp eq ptr %6, null
  br i1 %7, label %8, label %14

8:                                                ; preds = %1
  %9 = load ptr, ptr %3, align 8, !tbaa !5
  %10 = getelementptr inbounds %class.node, ptr %9, i32 0, i32 1
  %11 = load ptr, ptr %10, align 8, !tbaa !12
  %12 = icmp eq ptr %11, null
  br i1 %12, label %13, label %14

13:                                               ; preds = %8
  store ptr null, ptr %2, align 8
  br label %31

14:                                               ; preds = %8, %1
  %15 = load ptr, ptr %3, align 8, !tbaa !5
  %16 = getelementptr inbounds %class.node, ptr %15, i32 0, i32 2
  %17 = load ptr, ptr %16, align 8, !tbaa !9
  %18 = icmp ne ptr %17, null
  br i1 %18, label %19, label %27

19:                                               ; preds = %14
  %20 = load ptr, ptr %3, align 8, !tbaa !5
  %21 = getelementptr inbounds %class.node, ptr %20, i32 0, i32 2
  %22 = load ptr, ptr %21, align 8, !tbaa !9
  %23 = call noundef ptr @_Z15unlink_smallestP4node(ptr noundef %22)
  %24 = load ptr, ptr %3, align 8, !tbaa !5
  %25 = getelementptr inbounds %class.node, ptr %24, i32 0, i32 2
  store ptr %23, ptr %25, align 8, !tbaa !9
  %26 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %26, ptr %2, align 8
  br label %31

27:                                               ; preds = %14
  %28 = load ptr, ptr %3, align 8, !tbaa !5
  %29 = getelementptr inbounds %class.node, ptr %28, i32 0, i32 1
  %30 = load ptr, ptr %29, align 8, !tbaa !12
  store ptr %30, ptr %2, align 8
  br label %31

31:                                               ; preds = %27, %19, %13
  %32 = load ptr, ptr %2, align 8
  ret ptr %32
}

attributes #0 = { mustprogress 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++ TBAA"}
!9 = !{!10, !6, i64 16}
!10 = !{!"_ZTS4node", !11, i64 0, !6, i64 8, !6, i64 16}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !6, i64 8}


; 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: mustprogress nofree nosync nounwind memory(readwrite, inaccessiblemem: none) uwtable
define dso_local noundef ptr @_Z15unlink_smallestP4node(ptr noundef %0) local_unnamed_addr #0 {
  %2 = getelementptr inbounds i8, ptr %0, i64 16
  %3 = load ptr, ptr %2, align 8, !tbaa !5
  %4 = icmp eq ptr %3, null
  br i1 %4, label %common.ret, label %7

common.ret:                                       ; preds = %1
  %5 = getelementptr inbounds i8, ptr %0, i64 8
  %6 = load ptr, ptr %5, align 8, !tbaa !11
  br label %common.ret9

common.ret9:                                      ; preds = %7, %common.ret
  %common.ret9.op = phi ptr [ %6, %common.ret ], [ %0, %7 ]
  ret ptr %common.ret9.op

7:                                                ; preds = %1
  %8 = tail call noundef ptr @_Z15unlink_smallestP4node(ptr noundef nonnull %3)
  store ptr %8, ptr %2, align 8, !tbaa !5
  br label %common.ret9
}

attributes #0 = { mustprogress nofree nosync nounwind memory(readwrite, 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, !10, i64 16}
!6 = !{!"_ZTS4node", !7, i64 0, !10, i64 8, !10, i64 16}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = !{!6, !10, i64 8}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,InstCombinePass,JumpThreadingPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass