; LLVM IR from russellsayshi/CeeBeeServer :: lists (free_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.ll_item = type { ptr, ptr }

; 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 void @free_list(ptr noundef %0, ptr noundef %1) #1 {
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca ptr, align 8
  %7 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  store ptr %1, ptr %4, align 8, !tbaa !5
  %8 = load ptr, ptr %3, align 8, !tbaa !5
  %9 = icmp eq ptr %8, null
  br i1 %9, label %10, label %11

10:                                               ; preds = %2
  br label %37

11:                                               ; preds = %2
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #2
  %12 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %12, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #2
  store ptr null, ptr %6, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  store i32 1, ptr %7, align 4, !tbaa !9
  br label %13

13:                                               ; preds = %35, %11
  %14 = load i32, ptr %7, align 4, !tbaa !9
  %15 = icmp ne i32 %14, 0
  br i1 %15, label %16, label %36

16:                                               ; preds = %13
  %17 = load ptr, ptr %5, align 8, !tbaa !5
  %18 = getelementptr inbounds %struct.ll_item, ptr %17, i32 0, i32 1
  %19 = load ptr, ptr %18, align 8, !tbaa !11
  %20 = icmp eq ptr %19, null
  br i1 %20, label %21, label %26

21:                                               ; preds = %16
  store i32 0, ptr %7, align 4, !tbaa !9
  %22 = load ptr, ptr %4, align 8, !tbaa !5
  %23 = load ptr, ptr %5, align 8, !tbaa !5
  %24 = getelementptr inbounds %struct.ll_item, ptr %23, i32 0, i32 0
  %25 = load ptr, ptr %24, align 8, !tbaa !13
  call void %22(ptr noundef %25)
  br label %35

26:                                               ; preds = %16
  %27 = load ptr, ptr %5, align 8, !tbaa !5
  %28 = getelementptr inbounds %struct.ll_item, ptr %27, i32 0, i32 1
  %29 = load ptr, ptr %28, align 8, !tbaa !11
  store ptr %29, ptr %6, align 8, !tbaa !5
  %30 = load ptr, ptr %4, align 8, !tbaa !5
  %31 = load ptr, ptr %5, align 8, !tbaa !5
  %32 = getelementptr inbounds %struct.ll_item, ptr %31, i32 0, i32 0
  %33 = load ptr, ptr %32, align 8, !tbaa !13
  call void %30(ptr noundef %33)
  %34 = load ptr, ptr %6, align 8, !tbaa !5
  store ptr %34, ptr %5, align 8, !tbaa !5
  br label %35

35:                                               ; preds = %26, %21
  br label %13, !llvm.loop !14

36:                                               ; preds = %13
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #2
  br label %37

37:                                               ; preds = %36, %10
  ret void
}

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 8}
!12 = !{!"ll_item", !6, i64 0, !6, i64 8}
!13 = !{!12, !6, i64 0}
!14 = distinct !{!14, !15}
!15 = !{!"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 void @free_list(ptr noundef readonly %0, ptr nocapture noundef readonly %1) local_unnamed_addr #0 {
  %3 = icmp eq ptr %0, null
  br i1 %3, label %.loopexit, label %.preheader.preheader

.preheader.preheader:                             ; preds = %2
  %4 = getelementptr inbounds i8, ptr %0, i64 8
  %5 = load ptr, ptr %4, align 8, !tbaa !5
  %6 = icmp eq ptr %5, null
  br i1 %6, label %.loopexit.loopexit, label %.preheader

.preheader:                                       ; preds = %.preheader.preheader, %.preheader
  %7 = phi ptr [ %10, %.preheader ], [ %5, %.preheader.preheader ]
  %.091315 = phi ptr [ %7, %.preheader ], [ %0, %.preheader.preheader ]
  %8 = load ptr, ptr %.091315, align 8, !tbaa !10
  tail call void %1(ptr noundef %8) #1
  %9 = getelementptr inbounds i8, ptr %7, i64 8
  %10 = load ptr, ptr %9, align 8, !tbaa !5
  %11 = icmp eq ptr %10, null
  br i1 %11, label %.loopexit.loopexit, label %.preheader, !llvm.loop !11

.loopexit.loopexit:                               ; preds = %.preheader, %.preheader.preheader
  %.0913.lcssa = phi ptr [ %0, %.preheader.preheader ], [ %7, %.preheader ]
  %12 = load ptr, ptr %.0913.lcssa, align 8, !tbaa !10
  tail call void %1(ptr noundef %12) #1
  br label %.loopexit

.loopexit:                                        ; preds = %.loopexit.loopexit, %2
  ret void
}

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 = { 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, !7, i64 8}
!6 = !{!"ll_item", !7, i64 0, !7, i64 8}
!7 = !{!"any pointer", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!6, !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}


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