; LLVM IR from Ayon-SSP/The-SDE-Prep :: 1]_Data Structures/2]_Linked List/Linked List Problems (stackusinglinkedlist)

; 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"

@first = external dso_local global ptr, align 8
@.str.3 = external hidden unnamed_addr constant [21 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.5 = external hidden unnamed_addr constant [25 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [5 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local void @create(ptr noundef, i32 noundef) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

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

declare i32 @printf(ptr noundef, ...) #2

; Function Attrs: nounwind uwtable
declare dso_local i32 @peeklist(i32 noundef) #0

; Function Attrs: nounwind uwtable
define dso_local i32 @main() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca ptr, align 8
  %4 = alloca i64, align 8
  %5 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #4
  %6 = call i32 (ptr, ...) @printf(ptr noundef @.str.3)
  %7 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.4, ptr noundef %2)
  %8 = load i32, ptr %2, align 4, !tbaa !5
  %9 = zext i32 %8 to i64
  %10 = call ptr @llvm.stacksave.p0()
  store ptr %10, ptr %3, align 8
  %11 = alloca i32, i64 %9, align 16
  store i64 %9, ptr %4, align 8
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #4
  store i32 0, ptr %5, align 4, !tbaa !5
  br label %12

12:                                               ; preds = %22, %0
  %13 = load i32, ptr %5, align 4, !tbaa !5
  %14 = load i32, ptr %2, align 4, !tbaa !5
  %15 = icmp slt i32 %13, %14
  br i1 %15, label %17, label %16

16:                                               ; preds = %12
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #4
  br label %25

17:                                               ; preds = %12
  %18 = load i32, ptr %5, align 4, !tbaa !5
  %19 = sext i32 %18 to i64
  %20 = getelementptr inbounds i32, ptr %11, i64 %19
  %21 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.4, ptr noundef %20)
  br label %22

22:                                               ; preds = %17
  %23 = load i32, ptr %5, align 4, !tbaa !5
  %24 = add nsw i32 %23, 1
  store i32 %24, ptr %5, align 4, !tbaa !5
  br label %12, !llvm.loop !9

25:                                               ; preds = %16
  %26 = load i32, ptr %2, align 4, !tbaa !5
  call void @create(ptr noundef %11, i32 noundef %26)
  %27 = call i32 (ptr, ...) @printf(ptr noundef @.str.5)
  %28 = load ptr, ptr @first, align 8, !tbaa !11
  call void @display(ptr noundef %28)
  %29 = call i32 @peeklist(i32 noundef 3)
  %30 = call i32 (ptr, ...) @printf(ptr noundef @.str.6, i32 noundef %29)
  %31 = load ptr, ptr %3, align 8
  call void @llvm.stackrestore.p0(ptr %31)
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #4
  %32 = load i32, ptr %1, align 4
  ret i32 %32
}

declare i32 @__isoc99_scanf(ptr noundef, ...) #2

; Function Attrs: nocallback nofree nosync nounwind willreturn
declare ptr @llvm.stacksave.p0() #3

; Function Attrs: nocallback nofree nosync nounwind willreturn
declare void @llvm.stackrestore.p0(ptr) #3

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 = { "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 = { nocallback nofree nosync nounwind willreturn }
attributes #4 = { 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = !{!12, !12, i64 0}
!12 = !{!"any pointer", !7, i64 0}


; 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"

@first = external dso_local local_unnamed_addr global ptr, align 8
@.str.3 = external hidden unnamed_addr constant [21 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.5 = external hidden unnamed_addr constant [25 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [5 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local void @create(ptr noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

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

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

; Function Attrs: nounwind uwtable
declare dso_local i32 @peeklist(i32 noundef) local_unnamed_addr #0

; Function Attrs: nounwind uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #4
  %2 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.3)
  %3 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.4, ptr noundef nonnull %1)
  %4 = load i32, ptr %1, align 4, !tbaa !5
  %5 = zext i32 %4 to i64
  %6 = call ptr @llvm.stacksave.p0()
  %7 = alloca i32, i64 %5, align 16
  %8 = load i32, ptr %1, align 4, !tbaa !5
  %9 = icmp sgt i32 %8, 0
  br i1 %9, label %.lr.ph, label %._crit_edge

._crit_edge:                                      ; preds = %.lr.ph, %0
  %.lcssa = phi i32 [ %8, %0 ], [ %16, %.lr.ph ]
  call void @create(ptr noundef nonnull %7, i32 noundef %.lcssa)
  %10 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.5)
  %11 = load ptr, ptr @first, align 8, !tbaa !9
  call void @display(ptr noundef %11)
  %12 = call i32 @peeklist(i32 noundef 3)
  %13 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.6, i32 noundef %12)
  call void @llvm.stackrestore.p0(ptr %6)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #4
  ret i32 0

.lr.ph:                                           ; preds = %0, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %0 ]
  %14 = getelementptr inbounds i32, ptr %7, i64 %indvars.iv
  %15 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.4, ptr noundef nonnull %14)
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %16 = load i32, ptr %1, align 4, !tbaa !5
  %17 = sext i32 %16 to i64
  %18 = icmp slt i64 %indvars.iv.next, %17
  br i1 %18, label %.lr.ph, label %._crit_edge, !llvm.loop !11
}

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn
declare ptr @llvm.stacksave.p0() #3

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn
declare void @llvm.stackrestore.p0(ptr) #3

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 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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 #3 = { mustprogress nocallback nofree nosync nounwind willreturn }
attributes #4 = { 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}


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