; LLVM IR from ahampriyanshu/algo-ds-101 :: Data-Structures/LinkedList/Singly_Linked_List/LoopDetection.ll (Z10detectLoopP4Node)

; 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.Node = 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: nobuiltin allocsize(0)
declare noundef nonnull ptr @_Znwm(i64 noundef) #1

; 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
declare dso_local noundef i32 @_Z8distanceP4NodeS0_(ptr noundef, ptr noundef) #2

; Function Attrs: mustprogress uwtable
define dso_local noundef zeroext i1 @_Z10detectLoopP4Node(ptr noundef %0) #3 {
  %2 = alloca i1, align 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
  %8 = alloca i32, align 4
  %9 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  %10 = call noalias noundef nonnull ptr @_Znwm(i64 noundef 16) #5
  store ptr %10, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #4
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #4
  %11 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %11, ptr %5, align 8, !tbaa !5
  %12 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %12, ptr %6, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #4
  store i32 0, ptr %7, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #4
  store i32 -1, ptr %8, align 4, !tbaa !9
  br label %13

13:                                               ; preds = %22, %1
  %14 = load i32, ptr %7, align 4, !tbaa !9
  %15 = load i32, ptr %8, align 4, !tbaa !9
  %16 = icmp sgt i32 %14, %15
  br i1 %16, label %17, label %20

17:                                               ; preds = %13
  %18 = load ptr, ptr %6, align 8, !tbaa !5
  %19 = icmp ne ptr %18, null
  br label %20

20:                                               ; preds = %17, %13
  %21 = phi i1 [ false, %13 ], [ %19, %17 ]
  br i1 %21, label %22, label %30

22:                                               ; preds = %20
  %23 = load i32, ptr %7, align 4, !tbaa !9
  store i32 %23, ptr %8, align 4, !tbaa !9
  %24 = load ptr, ptr %5, align 8, !tbaa !5
  %25 = load ptr, ptr %6, align 8, !tbaa !5
  %26 = call noundef i32 @_Z8distanceP4NodeS0_(ptr noundef %24, ptr noundef %25)
  store i32 %26, ptr %7, align 4, !tbaa !9
  %27 = load ptr, ptr %6, align 8, !tbaa !5
  %28 = getelementptr inbounds %struct.Node, ptr %27, i32 0, i32 1
  %29 = load ptr, ptr %28, align 8, !tbaa !11
  store ptr %29, ptr %6, align 8, !tbaa !5
  br label %13, !llvm.loop !13

30:                                               ; preds = %20
  %31 = load ptr, ptr %6, align 8, !tbaa !5
  %32 = icmp eq ptr %31, null
  br i1 %32, label %33, label %34

33:                                               ; preds = %30
  store i1 false, ptr %2, align 1
  store i32 1, ptr %9, align 4
  br label %35

34:                                               ; preds = %30
  store i1 true, ptr %2, align 1
  store i32 1, ptr %9, align 4
  br label %35

35:                                               ; preds = %34, %33
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #4
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  %36 = load i1, ptr %2, align 1
  ret i1 %36
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { nobuiltin allocsize(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 = { 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 #3 = { 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 #4 = { nounwind }
attributes #5 = { builtin allocsize(0) }

!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 = !{!"_ZTS4Node", !10, i64 0, !6, i64 8}
!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: mustprogress nounwind uwtable
declare dso_local noundef i32 @_Z8distanceP4NodeS0_(ptr noundef, ptr noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef zeroext i1 @_Z10detectLoopP4Node(ptr noundef %0) local_unnamed_addr #0 {
  %.not = icmp eq ptr %0, null
  br i1 %.not, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %1, %.lr.ph
  %.01014 = phi i32 [ %2, %.lr.ph ], [ 0, %1 ]
  %.01113 = phi ptr [ %4, %.lr.ph ], [ %0, %1 ]
  %2 = tail call noundef i32 @_Z8distanceP4NodeS0_(ptr noundef nonnull %0, ptr noundef nonnull %.01113)
  %3 = getelementptr inbounds i8, ptr %.01113, i64 8
  %4 = load ptr, ptr %3, align 8, !tbaa !5
  %5 = icmp sgt i32 %2, %.01014
  %6 = icmp ne ptr %4, null
  %7 = select i1 %5, i1 %6, i1 false
  br i1 %7, label %.lr.ph, label %._crit_edge, !llvm.loop !11

._crit_edge:                                      ; preds = %.lr.ph, %1
  %.lcssa = phi i1 [ false, %1 ], [ %6, %.lr.ph ]
  ret i1 %.lcssa
}

attributes #0 = { 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" }

!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 = !{!"_ZTS4Node", !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"}


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