; LLVM IR from yinqiwen/ardb :: src/common/channel/timer/timer_task_queue.ll (ZN4ardb14TimerTaskQueue5ClearEv)

; 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.ardb::TimerTaskQueue" = type { ptr, i32, i32 }

; 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: mustprogress nounwind uwtable
define dso_local void @_ZN4ardb14TimerTaskQueue5ClearEv(ptr noundef nonnull align 8 dereferenceable(16) %0) #1 align 2 {
  %2 = alloca ptr, align 8
  %3 = alloca i32, align 4
  store ptr %0, ptr %2, align 8, !tbaa !5
  %4 = load ptr, ptr %2, align 8
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #2
  store i32 1, ptr %3, align 4, !tbaa !9
  br label %5

5:                                                ; preds = %17, %1
  %6 = load i32, ptr %3, align 4, !tbaa !9
  %7 = getelementptr inbounds %"class.ardb::TimerTaskQueue", ptr %4, i32 0, i32 2
  %8 = load i32, ptr %7, align 4, !tbaa !11
  %9 = icmp ule i32 %6, %8
  br i1 %9, label %11, label %10

10:                                               ; preds = %5
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #2
  br label %20

11:                                               ; preds = %5
  %12 = getelementptr inbounds %"class.ardb::TimerTaskQueue", ptr %4, i32 0, i32 0
  %13 = load ptr, ptr %12, align 8, !tbaa !13
  %14 = load i32, ptr %3, align 4, !tbaa !9
  %15 = zext i32 %14 to i64
  %16 = getelementptr inbounds ptr, ptr %13, i64 %15
  store ptr null, ptr %16, align 8, !tbaa !5
  br label %17

17:                                               ; preds = %11
  %18 = load i32, ptr %3, align 4, !tbaa !9
  %19 = add i32 %18, 1
  store i32 %19, ptr %3, align 4, !tbaa !9
  br label %5, !llvm.loop !14

20:                                               ; preds = %10
  %21 = getelementptr inbounds %"class.ardb::TimerTaskQueue", ptr %4, i32 0, i32 2
  store i32 0, ptr %21, align 4, !tbaa !11
  ret void
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { mustprogress 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++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{!12, !10, i64 12}
!12 = !{!"_ZTSN4ardb14TimerTaskQueueE", !6, i64 0, !10, i64 8, !10, i64 12}
!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: mustprogress nofree norecurse nosync nounwind memory(write, argmem: readwrite, inaccessiblemem: none) uwtable
define dso_local void @_ZN4ardb14TimerTaskQueue5ClearEv(ptr nocapture noundef nonnull align 8 dereferenceable(16) %0) local_unnamed_addr #0 align 2 {
  %2 = getelementptr inbounds i8, ptr %0, i64 12
  %3 = load i32, ptr %2, align 4, !tbaa !5
  %.not3 = icmp eq i32 %3, 0
  br i1 %.not3, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %1
  %4 = add i32 %3, 1
  %umax = tail call i32 @llvm.umax.i32(i32 %4, i32 2)
  %wide.trip.count = zext i32 %umax to i64
  %5 = add nsw i64 %wide.trip.count, -1
  %6 = add nsw i64 %wide.trip.count, -2
  %xtraiter = and i64 %5, 3
  %7 = icmp ult i64 %6, 3
  br i1 %7, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph.preheader.new

.lr.ph.preheader.new:                             ; preds = %.lr.ph.preheader
  %unroll_iter = and i64 %5, -4
  br label %.lr.ph

._crit_edge.loopexit.unr-lcssa:                   ; preds = %.lr.ph, %.lr.ph.preheader
  %indvars.iv.unr = phi i64 [ 1, %.lr.ph.preheader ], [ %indvars.iv.next.3, %.lr.ph ]
  %lcmp.mod.not = icmp eq i64 %xtraiter, 0
  br i1 %lcmp.mod.not, label %._crit_edge, label %.lr.ph.epil

.lr.ph.epil:                                      ; preds = %._crit_edge.loopexit.unr-lcssa, %.lr.ph.epil
  %indvars.iv.epil = phi i64 [ %indvars.iv.next.epil, %.lr.ph.epil ], [ %indvars.iv.unr, %._crit_edge.loopexit.unr-lcssa ]
  %epil.iter = phi i64 [ %epil.iter.next, %.lr.ph.epil ], [ 0, %._crit_edge.loopexit.unr-lcssa ]
  %8 = load ptr, ptr %0, align 8, !tbaa !11
  %9 = getelementptr inbounds ptr, ptr %8, i64 %indvars.iv.epil
  store ptr null, ptr %9, align 8, !tbaa !12
  %indvars.iv.next.epil = add nuw nsw i64 %indvars.iv.epil, 1
  %epil.iter.next = add i64 %epil.iter, 1
  %epil.iter.cmp.not = icmp eq i64 %epil.iter.next, %xtraiter
  br i1 %epil.iter.cmp.not, label %._crit_edge, label %.lr.ph.epil, !llvm.loop !13

._crit_edge:                                      ; preds = %._crit_edge.loopexit.unr-lcssa, %.lr.ph.epil, %1
  store i32 0, ptr %2, align 4, !tbaa !5
  ret void

.lr.ph:                                           ; preds = %.lr.ph, %.lr.ph.preheader.new
  %indvars.iv = phi i64 [ 1, %.lr.ph.preheader.new ], [ %indvars.iv.next.3, %.lr.ph ]
  %niter = phi i64 [ 0, %.lr.ph.preheader.new ], [ %niter.next.3, %.lr.ph ]
  %10 = load ptr, ptr %0, align 8, !tbaa !11
  %11 = getelementptr inbounds ptr, ptr %10, i64 %indvars.iv
  store ptr null, ptr %11, align 8, !tbaa !12
  %12 = load ptr, ptr %0, align 8, !tbaa !11
  %13 = getelementptr inbounds ptr, ptr %12, i64 %indvars.iv
  %14 = getelementptr inbounds i8, ptr %13, i64 8
  store ptr null, ptr %14, align 8, !tbaa !12
  %15 = load ptr, ptr %0, align 8, !tbaa !11
  %16 = getelementptr inbounds ptr, ptr %15, i64 %indvars.iv
  %17 = getelementptr inbounds i8, ptr %16, i64 16
  store ptr null, ptr %17, align 8, !tbaa !12
  %18 = load ptr, ptr %0, align 8, !tbaa !11
  %19 = getelementptr inbounds ptr, ptr %18, i64 %indvars.iv
  %20 = getelementptr inbounds i8, ptr %19, i64 24
  store ptr null, ptr %20, align 8, !tbaa !12
  %indvars.iv.next.3 = add nuw nsw i64 %indvars.iv, 4
  %niter.next.3 = add i64 %niter, 4
  %niter.ncmp.3 = icmp eq i64 %niter.next.3, %unroll_iter
  br i1 %niter.ncmp.3, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph, !llvm.loop !15
}

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.umax.i32(i32, i32) #1

attributes #0 = { mustprogress nofree norecurse nosync nounwind memory(write, argmem: 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" }
attributes #1 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }

!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 12}
!6 = !{!"_ZTSN4ardb14TimerTaskQueueE", !7, i64 0, !10, i64 8, !10, i64 12}
!7 = !{!"any pointer", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = !{!"int", !8, i64 0}
!11 = !{!6, !7, i64 0}
!12 = !{!7, !7, i64 0}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.unroll.disable"}
!15 = distinct !{!15, !16}
!16 = !{!"llvm.loop.mustprogress"}


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