; LLVM IR from Shah-Shishir/Codeforces-Solutions :: 805B. 3-palindrome (main)

; 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"

@.str = external hidden unnamed_addr constant [3 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [5 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [2 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.5 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [2 x i8], align 1

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #3
  br label %6

6:                                                ; preds = %40, %0
  %7 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef %2)
  %8 = icmp ne i32 %7, -1
  br i1 %8, label %9, label %42

9:                                                ; preds = %6
  %10 = load i32, ptr %2, align 4, !tbaa !5
  %11 = sdiv i32 %10, 4
  store i32 %11, ptr %5, align 4, !tbaa !5
  store i32 1, ptr %3, align 4, !tbaa !5
  br label %12

12:                                               ; preds = %18, %9
  %13 = load i32, ptr %3, align 4, !tbaa !5
  %14 = load i32, ptr %5, align 4, !tbaa !5
  %15 = icmp sle i32 %13, %14
  br i1 %15, label %16, label %21

16:                                               ; preds = %12
  %17 = call i32 (ptr, ...) @printf(ptr noundef @.str.2)
  br label %18

18:                                               ; preds = %16
  %19 = load i32, ptr %3, align 4, !tbaa !5
  %20 = add nsw i32 %19, 1
  store i32 %20, ptr %3, align 4, !tbaa !5
  br label %12, !llvm.loop !9

21:                                               ; preds = %12
  %22 = load i32, ptr %2, align 4, !tbaa !5
  %23 = srem i32 %22, 4
  store i32 %23, ptr %4, align 4, !tbaa !5
  %24 = load i32, ptr %4, align 4, !tbaa !5
  %25 = icmp eq i32 %24, 1
  br i1 %25, label %26, label %28

26:                                               ; preds = %21
  %27 = call i32 (ptr, ...) @printf(ptr noundef @.str.3)
  br label %40

28:                                               ; preds = %21
  %29 = load i32, ptr %4, align 4, !tbaa !5
  %30 = icmp eq i32 %29, 2
  br i1 %30, label %31, label %33

31:                                               ; preds = %28
  %32 = call i32 (ptr, ...) @printf(ptr noundef @.str.4)
  br label %39

33:                                               ; preds = %28
  %34 = load i32, ptr %4, align 4, !tbaa !5
  %35 = icmp eq i32 %34, 3
  br i1 %35, label %36, label %38

36:                                               ; preds = %33
  %37 = call i32 (ptr, ...) @printf(ptr noundef @.str.5)
  br label %38

38:                                               ; preds = %36, %33
  br label %39

39:                                               ; preds = %38, %31
  br label %40

40:                                               ; preds = %39, %26
  %41 = call i32 (ptr, ...) @printf(ptr noundef @.str.6)
  br label %6, !llvm.loop !11

42:                                               ; preds = %6
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #3
  ret i32 0
}

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

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

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

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

attributes #0 = { mustprogress norecurse 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 = { 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++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}


; 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 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [5 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [2 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.5 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.6 = external hidden unnamed_addr constant [2 x i8], align 1
@switch.table.main = private unnamed_addr constant [3 x ptr] [ptr @.str.3, ptr @.str.4, ptr @.str.5], align 8

; Function Attrs: mustprogress nofree norecurse 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) #3
  %2 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull %1)
  %.not10 = icmp eq i32 %2, -1
  br i1 %.not10, label %._crit_edge13, label %.lr.ph12

.lr.ph12:                                         ; preds = %0, %12
  %3 = load i32, ptr %1, align 4, !tbaa !5
  %.not78 = icmp slt i32 %3, 4
  br i1 %.not78, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %.lr.ph12
  %4 = lshr i32 %3, 2
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %.lr.ph
  %.09 = phi i32 [ %6, %.lr.ph ], [ 1, %.lr.ph.preheader ]
  %5 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.2)
  %6 = add nuw nsw i32 %.09, 1
  %exitcond.not = icmp eq i32 %.09, %4
  br i1 %exitcond.not, label %._crit_edge.loopexit, label %.lr.ph, !llvm.loop !9

._crit_edge.loopexit:                             ; preds = %.lr.ph
  %.pre = load i32, ptr %1, align 4, !tbaa !5
  br label %._crit_edge

._crit_edge:                                      ; preds = %._crit_edge.loopexit, %.lr.ph12
  %7 = phi i32 [ %.pre, %._crit_edge.loopexit ], [ %3, %.lr.ph12 ]
  %8 = srem i32 %7, 4
  %switch.tableidx = add nsw i32 %8, -1
  %9 = icmp ult i32 %switch.tableidx, 3
  br i1 %9, label %switch.lookup, label %12

switch.lookup:                                    ; preds = %._crit_edge
  %10 = zext nneg i32 %switch.tableidx to i64
  %switch.gep = getelementptr inbounds [3 x ptr], ptr @switch.table.main, i64 0, i64 %10
  %switch.load = load ptr, ptr %switch.gep, align 8
  %11 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) %switch.load)
  br label %12

12:                                               ; preds = %._crit_edge, %switch.lookup
  %13 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.6)
  %14 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull %1)
  %.not = icmp eq i32 %14, -1
  br i1 %.not, label %._crit_edge13, label %.lr.ph12, !llvm.loop !11

._crit_edge13:                                    ; preds = %12, %0
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #3
  ret i32 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: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

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

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

attributes #0 = { mustprogress nofree norecurse 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 = { 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++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}


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