; LLVM IR from kaynewbie/algorithm :: algorithm/LeetCode/Easy (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
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #3
  %7 = load ptr, ptr %3, align 8, !tbaa !5
  %8 = icmp eq ptr %7, null
  br i1 %8, label %9, label %10

9:                                                ; preds = %1
  store ptr null, ptr %2, align 8
  store i32 1, ptr %6, align 4
  br label %40

10:                                               ; preds = %1
  %11 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %11, ptr %4, align 8, !tbaa !5
  %12 = load ptr, ptr %3, align 8, !tbaa !5
  %13 = getelementptr inbounds %struct.ListNode, ptr %12, i32 0, i32 1
  %14 = load ptr, ptr %13, align 8, !tbaa !9
  store ptr %14, ptr %5, align 8, !tbaa !5
  br label %15

15:                                               ; preds = %37, %10
  %16 = load ptr, ptr %5, align 8, !tbaa !5
  %17 = icmp ne ptr %16, null
  br i1 %17, label %18, label %38

18:                                               ; preds = %15
  %19 = load ptr, ptr %4, align 8, !tbaa !5
  %20 = load ptr, ptr %5, align 8, !tbaa !5
  %21 = call zeroext i1 @isDuplicate(ptr noundef %19, ptr noundef %20)
  br i1 %21, label %22, label %32

22:                                               ; preds = %18
  %23 = load ptr, ptr %5, align 8, !tbaa !5
  %24 = getelementptr inbounds %struct.ListNode, ptr %23, i32 0, i32 1
  %25 = load ptr, ptr %24, align 8, !tbaa !9
  %26 = load ptr, ptr %4, align 8, !tbaa !5
  %27 = getelementptr inbounds %struct.ListNode, ptr %26, i32 0, i32 1
  store ptr %25, ptr %27, align 8, !tbaa !9
  %28 = load ptr, ptr %5, align 8, !tbaa !5
  call void @free(ptr noundef %28) #3
  %29 = load ptr, ptr %4, align 8, !tbaa !5
  %30 = getelementptr inbounds %struct.ListNode, ptr %29, i32 0, i32 1
  %31 = load ptr, ptr %30, align 8, !tbaa !9
  store ptr %31, ptr %5, align 8, !tbaa !5
  br label %37

32:                                               ; preds = %18
  %33 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %33, ptr %4, align 8, !tbaa !5
  %34 = load ptr, ptr %5, align 8, !tbaa !5
  %35 = getelementptr inbounds %struct.ListNode, ptr %34, i32 0, i32 1
  %36 = load ptr, ptr %35, align 8, !tbaa !9
  store ptr %36, ptr %5, align 8, !tbaa !5
  br label %37

37:                                               ; preds = %32, %22
  br label %15, !llvm.loop !12

38:                                               ; preds = %15
  %39 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %39, ptr %2, align 8
  store i32 1, ptr %6, align 4
  br label %40

40:                                               ; preds = %38, %9
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #3
  %41 = load ptr, ptr %2, align 8
  ret ptr %41
}

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

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

; 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 = distinct !{!12, !13}
!13 = !{!"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 %3

3:                                                ; preds = %1
  %4 = getelementptr inbounds i8, ptr %0, i64 8
  %.018 = load ptr, ptr %4, align 8, !tbaa !5
  %.not19 = icmp eq ptr %.018, null
  br i1 %.not19, label %.loopexit, label %.lr.ph

.lr.ph:                                           ; preds = %3, %10
  %.021 = phi ptr [ %.0, %10 ], [ %.018, %3 ]
  %.01420 = phi ptr [ %.115, %10 ], [ %0, %3 ]
  %5 = tail call zeroext i1 @isDuplicate(ptr noundef nonnull %.01420, ptr noundef nonnull %.021)
  %6 = getelementptr inbounds i8, ptr %.021, i64 8
  br i1 %5, label %7, label %10

7:                                                ; preds = %.lr.ph
  %8 = load ptr, ptr %6, align 8, !tbaa !5
  %9 = getelementptr inbounds i8, ptr %.01420, i64 8
  store ptr %8, ptr %9, align 8, !tbaa !5
  tail call void @free(ptr noundef nonnull %.021) #2
  br label %10

10:                                               ; preds = %.lr.ph, %7
  %.115 = phi ptr [ %.01420, %7 ], [ %.021, %.lr.ph ]
  %.1.in = phi ptr [ %9, %7 ], [ %6, %.lr.ph ]
  %.0 = load ptr, ptr %.1.in, align 8, !tbaa !5
  %.not = icmp eq ptr %.0, null
  br i1 %.not, label %.loopexit, label %.lr.ph, !llvm.loop !11

.loopexit:                                        ; preds = %10, %3, %1
  ret ptr %0
}

; Function Attrs: nounwind uwtable
declare dso_local zeroext i1 @isDuplicate(ptr noundef, ptr noundef) local_unnamed_addr #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 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}


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