; LLVM IR from smv1999/CompetitiveProgrammingQuestionBank :: Data Structures/Linked Lists/Singly Linked List (Reverse_Nodes_in_K_Groups)

; 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: 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 uwtable
define dso_local noundef ptr @_Z13reverseKGroupP8ListNodei(ptr noundef %0, i32 noundef %1) #1 {
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  %7 = alloca ptr, align 8
  store ptr %0, ptr %3, align 8, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #2
  %8 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %8, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  store i32 0, ptr %6, align 4, !tbaa !9
  br label %9

9:                                                ; preds = %18, %2
  %10 = load ptr, ptr %5, align 8, !tbaa !5
  %11 = icmp ne ptr %10, null
  br i1 %11, label %12, label %16

12:                                               ; preds = %9
  %13 = load i32, ptr %6, align 4, !tbaa !9
  %14 = load i32, ptr %4, align 4, !tbaa !9
  %15 = icmp ne i32 %13, %14
  br label %16

16:                                               ; preds = %12, %9
  %17 = phi i1 [ false, %9 ], [ %15, %12 ]
  br i1 %17, label %18, label %24

18:                                               ; preds = %16
  %19 = load ptr, ptr %5, align 8, !tbaa !5
  %20 = getelementptr inbounds %struct.ListNode, ptr %19, i32 0, i32 1
  %21 = load ptr, ptr %20, align 8, !tbaa !11
  store ptr %21, ptr %5, align 8, !tbaa !5
  %22 = load i32, ptr %6, align 4, !tbaa !9
  %23 = add nsw i32 %22, 1
  store i32 %23, ptr %6, align 4, !tbaa !9
  br label %9, !llvm.loop !13

24:                                               ; preds = %16
  %25 = load i32, ptr %6, align 4, !tbaa !9
  %26 = load i32, ptr %4, align 4, !tbaa !9
  %27 = icmp eq i32 %25, %26
  br i1 %27, label %28, label %47

28:                                               ; preds = %24
  %29 = load ptr, ptr %5, align 8, !tbaa !5
  %30 = load i32, ptr %4, align 4, !tbaa !9
  %31 = call noundef ptr @_Z13reverseKGroupP8ListNodei(ptr noundef %29, i32 noundef %30)
  store ptr %31, ptr %5, align 8, !tbaa !5
  br label %32

32:                                               ; preds = %36, %28
  %33 = load i32, ptr %6, align 4, !tbaa !9
  %34 = add nsw i32 %33, -1
  store i32 %34, ptr %6, align 4, !tbaa !9
  %35 = icmp sgt i32 %33, 0
  br i1 %35, label %36, label %45

36:                                               ; preds = %32
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #2
  %37 = load ptr, ptr %3, align 8, !tbaa !5
  %38 = getelementptr inbounds %struct.ListNode, ptr %37, i32 0, i32 1
  %39 = load ptr, ptr %38, align 8, !tbaa !11
  store ptr %39, ptr %7, align 8, !tbaa !5
  %40 = load ptr, ptr %5, align 8, !tbaa !5
  %41 = load ptr, ptr %3, align 8, !tbaa !5
  %42 = getelementptr inbounds %struct.ListNode, ptr %41, i32 0, i32 1
  store ptr %40, ptr %42, align 8, !tbaa !11
  %43 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %43, ptr %5, align 8, !tbaa !5
  %44 = load ptr, ptr %7, align 8, !tbaa !5
  store ptr %44, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #2
  br label %32, !llvm.loop !15

45:                                               ; preds = %32
  %46 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %46, ptr %3, align 8, !tbaa !5
  br label %47

47:                                               ; preds = %45, %24
  %48 = load ptr, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #2
  ret ptr %48
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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" }
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, !6, i64 8}
!12 = !{!"_ZTS8ListNode", !10, i64 0, !6, i64 8}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}
!15 = distinct !{!15, !14}


; 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 @_Z13reverseKGroupP8ListNodei(ptr noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = icmp ne ptr %0, null
  %4 = icmp ne i32 %1, 0
  %5 = and i1 %3, %4
  br i1 %5, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %2, %.lr.ph
  %.01723 = phi i32 [ %8, %.lr.ph ], [ 0, %2 ]
  %.01922 = phi ptr [ %7, %.lr.ph ], [ %0, %2 ]
  %6 = getelementptr inbounds i8, ptr %.01922, i64 8
  %7 = load ptr, ptr %6, align 8, !tbaa !5
  %8 = add nuw nsw i32 %.01723, 1
  %9 = icmp ne ptr %7, null
  %10 = icmp ne i32 %8, %1
  %11 = select i1 %9, i1 %10, i1 false
  br i1 %11, label %.lr.ph, label %._crit_edge, !llvm.loop !11

._crit_edge:                                      ; preds = %.lr.ph, %2
  %.019.lcssa = phi ptr [ %0, %2 ], [ %7, %.lr.ph ]
  %.017.lcssa = phi i32 [ 0, %2 ], [ %8, %.lr.ph ]
  %12 = icmp eq i32 %.017.lcssa, %1
  br i1 %12, label %13, label %.loopexit

13:                                               ; preds = %._crit_edge
  %14 = tail call noundef ptr @_Z13reverseKGroupP8ListNodei(ptr noundef %.019.lcssa, i32 noundef %1)
  %15 = icmp sgt i32 %1, 0
  br i1 %15, label %.lr.ph29.preheader, label %.loopexit

.lr.ph29.preheader:                               ; preds = %13
  %xtraiter = and i32 %1, 7
  %lcmp.mod.not = icmp eq i32 %xtraiter, 0
  br i1 %lcmp.mod.not, label %.lr.ph29.prol.loopexit, label %.lr.ph29.prol

.lr.ph29.prol:                                    ; preds = %.lr.ph29.preheader, %.lr.ph29.prol
  %.027.prol = phi ptr [ %18, %.lr.ph29.prol ], [ %0, %.lr.ph29.preheader ]
  %.11826.prol = phi i32 [ %16, %.lr.ph29.prol ], [ %1, %.lr.ph29.preheader ]
  %.12025.prol = phi ptr [ %.027.prol, %.lr.ph29.prol ], [ %14, %.lr.ph29.preheader ]
  %prol.iter = phi i32 [ %prol.iter.next, %.lr.ph29.prol ], [ 0, %.lr.ph29.preheader ]
  %16 = add nsw i32 %.11826.prol, -1
  %17 = getelementptr inbounds i8, ptr %.027.prol, i64 8
  %18 = load ptr, ptr %17, align 8, !tbaa !5
  store ptr %.12025.prol, ptr %17, align 8, !tbaa !5
  %prol.iter.next = add i32 %prol.iter, 1
  %prol.iter.cmp.not = icmp eq i32 %prol.iter.next, %xtraiter
  br i1 %prol.iter.cmp.not, label %.lr.ph29.prol.loopexit, label %.lr.ph29.prol, !llvm.loop !13

.lr.ph29.prol.loopexit:                           ; preds = %.lr.ph29.prol, %.lr.ph29.preheader
  %.027.unr = phi ptr [ %0, %.lr.ph29.preheader ], [ %18, %.lr.ph29.prol ]
  %.11826.unr = phi i32 [ %1, %.lr.ph29.preheader ], [ %16, %.lr.ph29.prol ]
  %.12025.unr = phi ptr [ %14, %.lr.ph29.preheader ], [ %.027.prol, %.lr.ph29.prol ]
  %.027.lcssa.unr = phi ptr [ poison, %.lr.ph29.preheader ], [ %.027.prol, %.lr.ph29.prol ]
  %19 = icmp ult i32 %1, 8
  br i1 %19, label %.loopexit, label %.lr.ph29

.lr.ph29:                                         ; preds = %.lr.ph29.prol.loopexit, %.lr.ph29
  %.027 = phi ptr [ %36, %.lr.ph29 ], [ %.027.unr, %.lr.ph29.prol.loopexit ]
  %.11826 = phi i32 [ %34, %.lr.ph29 ], [ %.11826.unr, %.lr.ph29.prol.loopexit ]
  %.12025 = phi ptr [ %33, %.lr.ph29 ], [ %.12025.unr, %.lr.ph29.prol.loopexit ]
  %20 = getelementptr inbounds i8, ptr %.027, i64 8
  %21 = load ptr, ptr %20, align 8, !tbaa !5
  store ptr %.12025, ptr %20, align 8, !tbaa !5
  %22 = getelementptr inbounds i8, ptr %21, i64 8
  %23 = load ptr, ptr %22, align 8, !tbaa !5
  store ptr %.027, ptr %22, align 8, !tbaa !5
  %24 = getelementptr inbounds i8, ptr %23, i64 8
  %25 = load ptr, ptr %24, align 8, !tbaa !5
  store ptr %21, ptr %24, align 8, !tbaa !5
  %26 = getelementptr inbounds i8, ptr %25, i64 8
  %27 = load ptr, ptr %26, align 8, !tbaa !5
  store ptr %23, ptr %26, align 8, !tbaa !5
  %28 = getelementptr inbounds i8, ptr %27, i64 8
  %29 = load ptr, ptr %28, align 8, !tbaa !5
  store ptr %25, ptr %28, align 8, !tbaa !5
  %30 = getelementptr inbounds i8, ptr %29, i64 8
  %31 = load ptr, ptr %30, align 8, !tbaa !5
  store ptr %27, ptr %30, align 8, !tbaa !5
  %32 = getelementptr inbounds i8, ptr %31, i64 8
  %33 = load ptr, ptr %32, align 8, !tbaa !5
  store ptr %29, ptr %32, align 8, !tbaa !5
  %34 = add nsw i32 %.11826, -8
  %35 = getelementptr inbounds i8, ptr %33, i64 8
  %36 = load ptr, ptr %35, align 8, !tbaa !5
  store ptr %31, ptr %35, align 8, !tbaa !5
  %37 = add i32 %.11826, -9
  %38 = icmp ult i32 %37, -2
  br i1 %38, label %.lr.ph29, label %.loopexit, !llvm.loop !15

.loopexit:                                        ; preds = %.lr.ph29.prol.loopexit, %.lr.ph29, %13, %._crit_edge
  %.1 = phi ptr [ %0, %._crit_edge ], [ %14, %13 ], [ %.027.lcssa.unr, %.lr.ph29.prol.loopexit ], [ %33, %.lr.ph29 ]
  ret ptr %.1
}

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 8}
!6 = !{!"_ZTS8ListNode", !7, i64 0, !10, i64 8}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.unroll.disable"}
!15 = distinct !{!15, !12}


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