; LLVM IR from Shah-Shishir/Codeforces-Solutions :: 981A. Antipalindrome.ll (Z6retLenPci)

; 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"

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_Z7isPalinPci(ptr noundef, i32 noundef) #0

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z6retLenPci(ptr noundef %0, i32 noundef %1) #1 {
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  %6 = load i32, ptr %5, align 4, !tbaa !9
  %7 = icmp eq i32 %6, 0
  br i1 %7, label %8, label %9

8:                                                ; preds = %2
  store i32 0, ptr %3, align 4
  br label %21

9:                                                ; preds = %2
  %10 = load ptr, ptr %4, align 8, !tbaa !5
  %11 = load i32, ptr %5, align 4, !tbaa !9
  %12 = call noundef zeroext i1 @_Z7isPalinPci(ptr noundef %10, i32 noundef %11)
  br i1 %12, label %13, label %18

13:                                               ; preds = %9
  %14 = load ptr, ptr %4, align 8, !tbaa !5
  %15 = load i32, ptr %5, align 4, !tbaa !9
  %16 = add nsw i32 %15, -1
  store i32 %16, ptr %5, align 4, !tbaa !9
  %17 = call noundef i32 @_Z6retLenPci(ptr noundef %14, i32 noundef %16)
  br label %20

18:                                               ; preds = %9
  %19 = load i32, ptr %5, align 4, !tbaa !9
  store i32 %19, ptr %3, align 4
  br label %21

20:                                               ; preds = %13
  unreachable

21:                                               ; preds = %18, %8
  %22 = load i32, ptr %3, align 4
  ret i32 %22
}

attributes #0 = { mustprogress 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 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++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !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"

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_Z7isPalinPci(ptr noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z6retLenPci(ptr noundef %0, i32 noundef returned %1) local_unnamed_addr #0 {
  %3 = icmp eq i32 %1, 0
  br i1 %3, label %9, label %4

4:                                                ; preds = %2
  %5 = tail call noundef zeroext i1 @_Z7isPalinPci(ptr noundef %0, i32 noundef %1)
  br i1 %5, label %6, label %9

6:                                                ; preds = %4
  %7 = add nsw i32 %1, -1
  %8 = tail call noundef i32 @_Z6retLenPci(ptr noundef %0, i32 noundef %7)
  unreachable

9:                                                ; preds = %4, %2
  ret i32 %1
}

attributes #0 = { mustprogress 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)"}


; Effective O3 passes: CorrelatedValuePropagationPass,GlobalOptPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass