; LLVM IR from ritikbanger/Hacktoberfest2022-DSA :: 10. Linked List/cpp (single_student_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 { %struct.data, ptr }
%struct.data = type { i32, i32, i8 }

@.str.1 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.5 = external hidden unnamed_addr constant [51 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

declare i32 @__isoc99_scanf(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 @update(ptr noundef %0, i32 noundef %1) #2 {
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  %5 = 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) #3
  %6 = load ptr, ptr %3, align 8, !tbaa !5
  %7 = load ptr, ptr %6, align 8, !tbaa !5
  store ptr %7, ptr %5, align 8, !tbaa !5
  br label %8

8:                                                ; preds = %23, %2
  %9 = load ptr, ptr %5, align 8, !tbaa !5
  %10 = icmp ne ptr %9, null
  br i1 %10, label %11, label %24

11:                                               ; preds = %8
  %12 = load ptr, ptr %5, align 8, !tbaa !5
  %13 = getelementptr inbounds %struct.node, ptr %12, i32 0, i32 0
  %14 = getelementptr inbounds %struct.data, ptr %13, i32 0, i32 0
  %15 = load i32, ptr %14, align 8, !tbaa !11
  %16 = load i32, ptr %4, align 4, !tbaa !9
  %17 = icmp eq i32 %15, %16
  br i1 %17, label %18, label %19

18:                                               ; preds = %11
  br label %24

19:                                               ; preds = %11
  %20 = load ptr, ptr %5, align 8, !tbaa !5
  %21 = getelementptr inbounds %struct.node, ptr %20, i32 0, i32 1
  %22 = load ptr, ptr %21, align 8, !tbaa !14
  store ptr %22, ptr %5, align 8, !tbaa !5
  br label %23

23:                                               ; preds = %19
  br label %8, !llvm.loop !15

24:                                               ; preds = %18, %8
  %25 = call i32 (ptr, ...) @printf(ptr noundef @.str.5)
  %26 = load ptr, ptr %5, align 8, !tbaa !5
  %27 = getelementptr inbounds %struct.node, ptr %26, i32 0, i32 0
  %28 = getelementptr inbounds %struct.data, ptr %27, i32 0, i32 1
  %29 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.1, ptr noundef %28)
  %30 = load ptr, ptr %5, align 8, !tbaa !5
  %31 = getelementptr inbounds %struct.node, ptr %30, i32 0, i32 0
  %32 = getelementptr inbounds %struct.data, ptr %31, i32 0, i32 2
  %33 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.2, ptr noundef %32)
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #3
  ret void
}

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 }

!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", !13, i64 0, !6, i64 16}
!13 = !{!"data", !10, i64 0, !10, i64 4, !7, i64 8}
!14 = !{!12, !6, i64 16}
!15 = distinct !{!15, !16}
!16 = !{!"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 [3 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.5 = external hidden unnamed_addr constant [51 x i8], align 1

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #0

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #0

; Function Attrs: nofree nounwind uwtable
define dso_local void @update(ptr nocapture noundef readonly %0, i32 noundef %1) local_unnamed_addr #1 {
  %.06 = load ptr, ptr %0, align 8, !tbaa !5
  %.not7 = icmp eq ptr %.06, null
  br i1 %.not7, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %2, %5
  %.08 = phi ptr [ %.0, %5 ], [ %.06, %2 ]
  %3 = load i32, ptr %.08, align 8, !tbaa !9
  %4 = icmp eq i32 %3, %1
  br i1 %4, label %._crit_edge, label %5

5:                                                ; preds = %.lr.ph
  %6 = getelementptr inbounds i8, ptr %.08, i64 16
  %.0 = load ptr, ptr %6, align 8, !tbaa !5
  %.not = icmp eq ptr %.0, null
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !13

._crit_edge:                                      ; preds = %5, %.lr.ph, %2
  %.0.lcssa = phi ptr [ null, %2 ], [ %.08, %.lr.ph ], [ null, %5 ]
  %7 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.5)
  %8 = getelementptr inbounds i8, ptr %.0.lcssa, i64 4
  %9 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.1, ptr noundef nonnull %8)
  %10 = getelementptr inbounds i8, ptr %.0.lcssa, i64 8
  %11 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.2, ptr noundef nonnull %10)
  ret void
}

attributes #0 = { 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 #1 = { 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" }

!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, !12, i64 0}
!10 = !{!"node", !11, i64 0, !6, i64 16}
!11 = !{!"data", !12, i64 0, !12, i64 4, !7, i64 8}
!12 = !{!"int", !7, i64 0}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}


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