; LLVM IR from lolosssss/leetcode :: c (83_remove_duplicates_from_sorted_list)

; 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.ListNode = type { i32, ptr }

; Function Attrs: nounwind uwtable
define dso_local ptr @deleteDuplicates(ptr noundef %0) #0 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #3
  %7 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %7, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #3
  %8 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %8, ptr %5, align 8, !tbaa !5
  %9 = load ptr, ptr %3, align 8, !tbaa !5
  %10 = icmp eq ptr %9, null
  br i1 %10, label %11, label %12

11:                                               ; preds = %1
  store ptr null, ptr %2, align 8
  store i32 1, ptr %6, align 4
  br label %42

12:                                               ; preds = %1
  %13 = load ptr, ptr %4, align 8, !tbaa !5
  %14 = getelementptr inbounds %struct.ListNode, ptr %13, i32 0, i32 1
  %15 = load ptr, ptr %14, align 8, !tbaa !9
  store ptr %15, ptr %4, align 8, !tbaa !5
  br label %16

16:                                               ; preds = %36, %12
  %17 = load ptr, ptr %4, align 8, !tbaa !5
  %18 = icmp ne ptr %17, null
  br i1 %18, label %19, label %40

19:                                               ; preds = %16
  %20 = load ptr, ptr %5, align 8, !tbaa !5
  %21 = getelementptr inbounds %struct.ListNode, ptr %20, i32 0, i32 0
  %22 = load i32, ptr %21, align 8, !tbaa !12
  %23 = load ptr, ptr %4, align 8, !tbaa !5
  %24 = getelementptr inbounds %struct.ListNode, ptr %23, i32 0, i32 0
  %25 = load i32, ptr %24, align 8, !tbaa !12
  %26 = icmp eq i32 %22, %25
  br i1 %26, label %27, label %34

27:                                               ; preds = %19
  %28 = load ptr, ptr %4, align 8, !tbaa !5
  %29 = getelementptr inbounds %struct.ListNode, ptr %28, i32 0, i32 1
  %30 = load ptr, ptr %29, align 8, !tbaa !9
  %31 = load ptr, ptr %5, align 8, !tbaa !5
  %32 = getelementptr inbounds %struct.ListNode, ptr %31, i32 0, i32 1
  store ptr %30, ptr %32, align 8, !tbaa !9
  %33 = load ptr, ptr %4, align 8, !tbaa !5
  call void @free(ptr noundef %33) #3
  br label %36

34:                                               ; preds = %19
  %35 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %35, ptr %5, align 8, !tbaa !5
  br label %36

36:                                               ; preds = %34, %27
  %37 = load ptr, ptr %5, align 8, !tbaa !5
  %38 = getelementptr inbounds %struct.ListNode, ptr %37, i32 0, i32 1
  %39 = load ptr, ptr %38, align 8, !tbaa !9
  store ptr %39, ptr %4, align 8, !tbaa !5
  br label %16, !llvm.loop !13

40:                                               ; preds = %16
  %41 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %41, ptr %2, align 8
  store i32 1, ptr %6, align 4
  br label %42

42:                                               ; preds = %40, %11
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #3
  %43 = load ptr, ptr %2, align 8
  ret ptr %43
}

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: nounwind
declare void @free(ptr noundef) #2

; 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 "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 #3 = { 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, !6, i64 8}
!10 = !{!"ListNode", !11, i64 0, !6, i64 8}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !11, i64 0}
!13 = distinct !{!13, !14}
!14 = !{!"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: nounwind uwtable
define dso_local noundef ptr @deleteDuplicates(ptr noundef returned %0) local_unnamed_addr #0 {
  %2 = icmp eq ptr %0, null
  br i1 %2, label %.loopexit, label %.preheader

.preheader:                                       ; preds = %1
  %.014.in17 = getelementptr inbounds i8, ptr %0, i64 8
  %.01418 = load ptr, ptr %.014.in17, align 8, !tbaa !5
  %.not19 = icmp eq ptr %.01418, null
  br i1 %.not19, label %.loopexit, label %.lr.ph

.lr.ph:                                           ; preds = %.preheader, %9
  %.01422 = phi ptr [ %.014, %9 ], [ %.01418, %.preheader ]
  %.014.in21 = phi ptr [ %.014.in, %9 ], [ %.014.in17, %.preheader ]
  %.020 = phi ptr [ %.1, %9 ], [ %0, %.preheader ]
  %3 = load i32, ptr %.020, align 8, !tbaa !11
  %4 = load i32, ptr %.01422, align 8, !tbaa !11
  %5 = icmp eq i32 %3, %4
  br i1 %5, label %6, label %9

6:                                                ; preds = %.lr.ph
  %7 = getelementptr inbounds i8, ptr %.01422, i64 8
  %8 = load ptr, ptr %7, align 8, !tbaa !5
  store ptr %8, ptr %.014.in21, align 8, !tbaa !5
  tail call void @free(ptr noundef nonnull %.01422) #2
  br label %9

9:                                                ; preds = %.lr.ph, %6
  %.1 = phi ptr [ %.020, %6 ], [ %.01422, %.lr.ph ]
  %.014.in = getelementptr inbounds i8, ptr %.1, i64 8
  %.014 = load ptr, ptr %.014.in, align 8, !tbaa !5
  %.not = icmp eq ptr %.014, null
  br i1 %.not, label %.loopexit, label %.lr.ph, !llvm.loop !12

.loopexit:                                        ; preds = %9, %.preheader, %1
  ret ptr %0
}

; Function Attrs: mustprogress nounwind willreturn allockind("free") memory(argmem: readwrite, inaccessiblemem: readwrite)
declare void @free(ptr allocptr nocapture noundef) local_unnamed_addr #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 = { mustprogress nounwind willreturn allockind("free") memory(argmem: readwrite, inaccessiblemem: readwrite) "alloc-family"="malloc" "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, !10, i64 8}
!6 = !{!"ListNode", !7, i64 0, !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, !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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