; LLVM IR from HarshCasper/NeoAlgo :: C/ds (palindrome_doubly_linked_list)

; 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 [18 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [20 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [24 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local void @insert(ptr noundef, i8 noundef signext) #0

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

; Function Attrs: nounwind allocsize(0)
declare noalias ptr @malloc(i64 noundef) #2

; 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 i32 @palindrome(ptr noundef) #0

; Function Attrs: nounwind uwtable
define dso_local void @main() #0 {
  %1 = alloca ptr, align 8
  %2 = alloca [30 x i8], align 16
  %3 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 8, ptr %1) #4
  %4 = call noalias ptr @malloc(i64 noundef 24) #5
  store ptr %4, ptr %1, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 30, ptr %2) #4
  %5 = call i32 (ptr, ...) @printf(ptr noundef @.str)
  %6 = getelementptr inbounds [30 x i8], ptr %2, i64 0, i64 0
  %7 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.1, ptr noundef %6)
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #4
  store i32 0, ptr %3, align 4, !tbaa !9
  br label %8

8:                                                ; preds = %22, %0
  %9 = load i32, ptr %3, align 4, !tbaa !9
  %10 = sext i32 %9 to i64
  %11 = getelementptr inbounds [30 x i8], ptr %2, i64 0, i64 %10
  %12 = load i8, ptr %11, align 1, !tbaa !11
  %13 = sext i8 %12 to i32
  %14 = icmp ne i32 %13, 0
  br i1 %14, label %16, label %15

15:                                               ; preds = %8
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #4
  br label %25

16:                                               ; preds = %8
  %17 = load ptr, ptr %1, align 8, !tbaa !5
  %18 = load i32, ptr %3, align 4, !tbaa !9
  %19 = sext i32 %18 to i64
  %20 = getelementptr inbounds [30 x i8], ptr %2, i64 0, i64 %19
  %21 = load i8, ptr %20, align 1, !tbaa !11
  call void @insert(ptr noundef %17, i8 noundef signext %21)
  br label %22

22:                                               ; preds = %16
  %23 = load i32, ptr %3, align 4, !tbaa !9
  %24 = add nsw i32 %23, 1
  store i32 %24, ptr %3, align 4, !tbaa !9
  br label %8, !llvm.loop !12

25:                                               ; preds = %15
  %26 = load ptr, ptr %1, align 8, !tbaa !5
  %27 = call i32 @palindrome(ptr noundef %26)
  %28 = icmp eq i32 %27, 1
  br i1 %28, label %29, label %32

29:                                               ; preds = %25
  %30 = getelementptr inbounds [30 x i8], ptr %2, i64 0, i64 0
  %31 = call i32 (ptr, ...) @printf(ptr noundef @.str.2, ptr noundef %30)
  br label %35

32:                                               ; preds = %25
  %33 = getelementptr inbounds [30 x i8], ptr %2, i64 0, i64 0
  %34 = call i32 (ptr, ...) @printf(ptr noundef @.str.3, ptr noundef %33)
  br label %35

35:                                               ; preds = %32, %29
  call void @llvm.lifetime.end.p0(i64 30, ptr %2) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %1) #4
  ret void
}

declare i32 @printf(ptr noundef, ...) #3

declare i32 @__isoc99_scanf(ptr noundef, ...) #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 = { 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 #3 = { "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 = !{!7, !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"

@.str = external hidden unnamed_addr constant [18 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [20 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [24 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local void @insert(ptr noundef, i8 noundef signext) 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 nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite)
declare noalias noundef ptr @malloc(i64 noundef) 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

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

; Function Attrs: nounwind uwtable
define dso_local void @main() local_unnamed_addr #0 {
  %1 = alloca [30 x i8], align 16
  %2 = tail call noalias dereferenceable_or_null(24) ptr @malloc(i64 noundef 24) #4
  call void @llvm.lifetime.start.p0(i64 30, ptr nonnull %1) #5
  %3 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str)
  %4 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.1, ptr noundef nonnull %1)
  %5 = load i8, ptr %1, align 16, !tbaa !5
  %.not4 = icmp eq i8 %5, 0
  br i1 %.not4, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %.lr.ph, %0
  %6 = call i32 @palindrome(ptr noundef %2)
  %7 = icmp eq i32 %6, 1
  %.str.2..str.3 = select i1 %7, ptr @.str.2, ptr @.str.3
  %8 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) %.str.2..str.3, ptr noundef nonnull %1)
  call void @llvm.lifetime.end.p0(i64 30, ptr nonnull %1) #5
  ret void

.lr.ph:                                           ; preds = %0, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %0 ]
  %9 = phi i8 [ %11, %.lr.ph ], [ %5, %0 ]
  call void @insert(ptr noundef %2, i8 noundef signext %9)
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %10 = getelementptr inbounds [30 x i8], ptr %1, i64 0, i64 %indvars.iv.next
  %11 = load i8, ptr %10, align 1, !tbaa !5
  %.not = icmp eq i8 %11, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !8
}

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #3

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #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 = { 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 #3 = { 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 #4 = { nounwind allocsize(0) }
attributes #5 = { 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 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C/C++ TBAA"}
!8 = distinct !{!8, !9}
!9 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,IndVarSimplifyPass,InferAlignmentPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass,TailCallElimPass