; LLVM IR from div-bargali/Data-Structures-and-Algorithms :: C/Data-Structures/LinkedList (SelfLoopLinkedList)

; 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: nounwind uwtable
define dso_local i32 @detectAndRemoveLoop(ptr noundef %0) #0 {
  %2 = alloca i32, align 4
  %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) #2
  %7 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %7, ptr %4, align 8, !tbaa !5
  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
  br label %9

9:                                                ; preds = %37, %1
  %10 = load ptr, ptr %4, align 8, !tbaa !5
  %11 = icmp ne ptr %10, null
  br i1 %11, label %12, label %20

12:                                               ; preds = %9
  %13 = load ptr, ptr %5, align 8, !tbaa !5
  %14 = icmp ne ptr %13, null
  br i1 %14, label %15, label %20

15:                                               ; preds = %12
  %16 = load ptr, ptr %5, align 8, !tbaa !5
  %17 = getelementptr inbounds %struct.Node, ptr %16, i32 0, i32 1
  %18 = load ptr, ptr %17, align 8, !tbaa !9
  %19 = icmp ne ptr %18, null
  br label %20

20:                                               ; preds = %15, %12, %9
  %21 = phi i1 [ false, %12 ], [ false, %9 ], [ %19, %15 ]
  br i1 %21, label %22, label %38

22:                                               ; preds = %20
  %23 = load ptr, ptr %4, align 8, !tbaa !5
  %24 = getelementptr inbounds %struct.Node, ptr %23, i32 0, i32 1
  %25 = load ptr, ptr %24, align 8, !tbaa !9
  store ptr %25, ptr %4, align 8, !tbaa !5
  %26 = load ptr, ptr %5, align 8, !tbaa !5
  %27 = getelementptr inbounds %struct.Node, ptr %26, i32 0, i32 1
  %28 = load ptr, ptr %27, align 8, !tbaa !9
  %29 = getelementptr inbounds %struct.Node, ptr %28, i32 0, i32 1
  %30 = load ptr, ptr %29, align 8, !tbaa !9
  store ptr %30, ptr %5, align 8, !tbaa !5
  %31 = load ptr, ptr %4, align 8, !tbaa !5
  %32 = load ptr, ptr %5, align 8, !tbaa !5
  %33 = icmp eq ptr %31, %32
  br i1 %33, label %34, label %37

34:                                               ; preds = %22
  %35 = load ptr, ptr %4, align 8, !tbaa !5
  %36 = load ptr, ptr %3, align 8, !tbaa !5
  call void @removeLoop(ptr noundef %35, ptr noundef %36)
  store i32 1, ptr %2, align 4
  store i32 1, ptr %6, align 4
  br label %39

37:                                               ; preds = %22
  br label %9, !llvm.loop !12

38:                                               ; preds = %20
  store i32 0, ptr %2, align 4
  store i32 1, ptr %6, align 4
  br label %39

39:                                               ; preds = %38, %34
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #2
  %40 = load i32, ptr %2, align 4
  ret i32 %40
}

; 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 void @removeLoop(ptr noundef, ptr noundef) #0

; 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 }

!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 = !{!"Node", !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 range(i32 0, 2) i32 @detectAndRemoveLoop(ptr noundef %0) local_unnamed_addr #0 {
  br label %2

2:                                                ; preds = %8, %1
  %.012 = phi ptr [ %0, %1 ], [ %10, %8 ]
  %.0 = phi ptr [ %0, %1 ], [ %12, %8 ]
  %3 = icmp ne ptr %.012, null
  %4 = icmp ne ptr %.0, null
  %or.cond = and i1 %3, %4
  br i1 %or.cond, label %5, label %.critedge

5:                                                ; preds = %2
  %6 = getelementptr inbounds i8, ptr %.0, i64 8
  %7 = load ptr, ptr %6, align 8, !tbaa !5
  %.not = icmp eq ptr %7, null
  br i1 %.not, label %.critedge, label %8

8:                                                ; preds = %5
  %9 = getelementptr inbounds i8, ptr %.012, i64 8
  %10 = load ptr, ptr %9, align 8, !tbaa !5
  %11 = getelementptr inbounds i8, ptr %7, i64 8
  %12 = load ptr, ptr %11, align 8, !tbaa !5
  %13 = icmp eq ptr %10, %12
  br i1 %13, label %14, label %2, !llvm.loop !11

14:                                               ; preds = %8
  tail call void @removeLoop(ptr noundef %10, ptr noundef %0)
  br label %.critedge

.critedge:                                        ; preds = %5, %2, %14
  %.013 = phi i32 [ 1, %14 ], [ 0, %2 ], [ 0, %5 ]
  ret i32 %.013
}

; Function Attrs: nounwind uwtable
declare dso_local void @removeLoop(ptr noundef, ptr noundef) local_unnamed_addr #0

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" }

!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 = !{!"Node", !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: EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass,TailCallElimPass