; LLVM IR from ritikbanger/Hacktoberfest2022-DSA :: 36. C Programs (circular_linkedlist)

; 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 }

@.str.1 = external hidden unnamed_addr constant [22 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [3 x i8], align 1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

declare i32 @printf(ptr 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: nounwind uwtable
define dso_local void @insert_at_start(ptr noundef %0) #2 {
  %2 = alloca ptr, align 8
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #4
  %6 = call i32 (ptr, ...) @printf(ptr noundef @.str.1)
  %7 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.2, ptr noundef %3)
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  %8 = call noalias ptr @malloc(i64 noundef 16) #5
  store ptr %8, ptr %4, align 8, !tbaa !5
  %9 = load i32, ptr %3, align 4, !tbaa !9
  %10 = load ptr, ptr %4, align 8, !tbaa !5
  %11 = getelementptr inbounds %struct.node, ptr %10, i32 0, i32 0
  store i32 %9, ptr %11, align 8, !tbaa !11
  %12 = load ptr, ptr %2, align 8, !tbaa !5
  %13 = load ptr, ptr %12, align 8, !tbaa !5
  %14 = load ptr, ptr %4, align 8, !tbaa !5
  %15 = getelementptr inbounds %struct.node, ptr %14, i32 0, i32 1
  store ptr %13, ptr %15, align 8, !tbaa !13
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #4
  %16 = load ptr, ptr %2, align 8, !tbaa !5
  %17 = load ptr, ptr %16, align 8, !tbaa !5
  store ptr %17, ptr %5, align 8, !tbaa !5
  %18 = load ptr, ptr %2, align 8, !tbaa !5
  %19 = load ptr, ptr %18, align 8, !tbaa !5
  %20 = icmp ne ptr %19, null
  br i1 %20, label %21, label %37

21:                                               ; preds = %1
  br label %22

22:                                               ; preds = %29, %21
  %23 = load ptr, ptr %5, align 8, !tbaa !5
  %24 = getelementptr inbounds %struct.node, ptr %23, i32 0, i32 1
  %25 = load ptr, ptr %24, align 8, !tbaa !13
  %26 = load ptr, ptr %2, align 8, !tbaa !5
  %27 = load ptr, ptr %26, align 8, !tbaa !5
  %28 = icmp ne ptr %25, %27
  br i1 %28, label %29, label %33

29:                                               ; preds = %22
  %30 = load ptr, ptr %5, align 8, !tbaa !5
  %31 = getelementptr inbounds %struct.node, ptr %30, i32 0, i32 1
  %32 = load ptr, ptr %31, align 8, !tbaa !13
  store ptr %32, ptr %5, align 8, !tbaa !5
  br label %22, !llvm.loop !14

33:                                               ; preds = %22
  %34 = load ptr, ptr %4, align 8, !tbaa !5
  %35 = load ptr, ptr %5, align 8, !tbaa !5
  %36 = getelementptr inbounds %struct.node, ptr %35, i32 0, i32 1
  store ptr %34, ptr %36, align 8, !tbaa !13
  br label %41

37:                                               ; preds = %1
  %38 = load ptr, ptr %4, align 8, !tbaa !5
  %39 = load ptr, ptr %4, align 8, !tbaa !5
  %40 = getelementptr inbounds %struct.node, ptr %39, i32 0, i32 1
  store ptr %38, ptr %40, align 8, !tbaa !13
  br label %41

41:                                               ; preds = %37, %33
  %42 = load ptr, ptr %4, align 8, !tbaa !5
  %43 = load ptr, ptr %2, align 8, !tbaa !5
  store ptr %42, ptr %43, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #4
  ret void
}

declare i32 @__isoc99_scanf(ptr noundef, ...) #1

; Function Attrs: nounwind allocsize(0)
declare noalias ptr @malloc(i64 noundef) #3

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { "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 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 = { nounwind 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 #4 = { nounwind }
attributes #5 = { nounwind 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/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{!12, !10, i64 0}
!12 = !{!"node", !10, i64 0, !6, i64 8}
!13 = !{!12, !6, i64 8}
!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"

@.str.1 = external hidden unnamed_addr constant [22 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [3 x i8], align 1

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #1

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nofree nounwind uwtable
define dso_local void @insert_at_start(ptr nocapture noundef %0) local_unnamed_addr #2 {
  %2 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #4
  %3 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1)
  %4 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.2, ptr noundef nonnull %2)
  %5 = call noalias dereferenceable_or_null(16) ptr @malloc(i64 noundef 16) #5
  %6 = load i32, ptr %2, align 4, !tbaa !5
  store i32 %6, ptr %5, align 8, !tbaa !9
  %7 = load ptr, ptr %0, align 8, !tbaa !12
  %8 = getelementptr inbounds i8, ptr %5, i64 8
  store ptr %7, ptr %8, align 8, !tbaa !13
  %.not = icmp eq ptr %7, null
  br i1 %.not, label %13, label %.preheader

.preheader:                                       ; preds = %1, %.preheader
  %.0 = phi ptr [ %10, %.preheader ], [ %7, %1 ]
  %9 = getelementptr inbounds i8, ptr %.0, i64 8
  %10 = load ptr, ptr %9, align 8, !tbaa !13
  %.not16 = icmp eq ptr %10, %7
  br i1 %.not16, label %11, label %.preheader, !llvm.loop !14

11:                                               ; preds = %.preheader
  %12 = getelementptr inbounds i8, ptr %.0, i64 8
  br label %13

13:                                               ; preds = %1, %11
  %.sink = phi ptr [ %12, %11 ], [ %8, %1 ]
  store ptr %5, ptr %.sink, align 8, !tbaa !13
  store ptr %5, ptr %0, align 8, !tbaa !12
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #4
  ret void
}

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #1

; Function Attrs: mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite)
declare noalias noundef ptr @malloc(i64 noundef) local_unnamed_addr #3

attributes #0 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { nofree nounwind "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 = { nofree 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 nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite) "alloc-family"="malloc" "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 = { nounwind 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !6, i64 0}
!10 = !{!"node", !6, i64 0, !11, i64 8}
!11 = !{!"any pointer", !7, i64 0}
!12 = !{!11, !11, i64 0}
!13 = !{!10, !11, i64 8}
!14 = distinct !{!14, !15}
!15 = !{!"llvm.loop.mustprogress"}


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