; LLVM IR from facebook/redex :: service/regalloc (VirtualRegistersFile)

; 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"

%"class.regalloc::VirtualRegistersFile" = type { %"class.boost::dynamic_bitset" }
%"class.boost::dynamic_bitset" = type { %"class.std::vector", i64 }
%"class.std::vector" = type { %"struct.std::_Vector_base" }
%"struct.std::_Vector_base" = type { %"struct.std::_Vector_base<unsigned long, std::allocator<unsigned long>>::_Vector_impl" }
%"struct.std::_Vector_base<unsigned long, std::allocator<unsigned long>>::_Vector_impl" = type { %"struct.std::_Vector_base<unsigned long, std::allocator<unsigned long>>::_Vector_impl_data" }
%"struct.std::_Vector_base<unsigned long, std::allocator<unsigned long>>::_Vector_impl_data" = type { ptr, ptr, ptr }

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress uwtable
define dso_local noundef zeroext i16 @_ZNK8regalloc20VirtualRegistersFile22find_free_range_at_endEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #1 align 2 {
  %2 = alloca i16, align 2
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  %6 = load ptr, ptr %3, align 8
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  %7 = getelementptr inbounds %"class.regalloc::VirtualRegistersFile", ptr %6, i32 0, i32 0
  %8 = call noundef i64 @_ZNK5boost14dynamic_bitsetImSaImEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32) %7) #3
  %9 = sub i64 %8, 1
  %10 = trunc i64 %9 to i32
  store i32 %10, ptr %4, align 4, !tbaa !9
  br label %11

11:                                               ; preds = %25, %1
  %12 = load i32, ptr %4, align 4, !tbaa !9
  %13 = icmp sge i32 %12, 0
  br i1 %13, label %15, label %14

14:                                               ; preds = %11
  store i32 2, ptr %5, align 4
  br label %28

15:                                               ; preds = %11
  %16 = getelementptr inbounds %"class.regalloc::VirtualRegistersFile", ptr %6, i32 0, i32 0
  %17 = load i32, ptr %4, align 4, !tbaa !9
  %18 = sext i32 %17 to i64
  %19 = call noundef zeroext i1 @_ZNK5boost14dynamic_bitsetImSaImEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %16, i64 noundef %18)
  br i1 %19, label %24, label %20

20:                                               ; preds = %15
  %21 = load i32, ptr %4, align 4, !tbaa !9
  %22 = add nsw i32 %21, 1
  %23 = trunc i32 %22 to i16
  store i16 %23, ptr %2, align 2
  store i32 1, ptr %5, align 4
  br label %28

24:                                               ; preds = %15
  br label %25

25:                                               ; preds = %24
  %26 = load i32, ptr %4, align 4, !tbaa !9
  %27 = add nsw i32 %26, -1
  store i32 %27, ptr %4, align 4, !tbaa !9
  br label %11, !llvm.loop !11

28:                                               ; preds = %20, %14
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  %29 = load i32, ptr %5, align 4
  switch i32 %29, label %33 [
    i32 2, label %30
    i32 1, label %31
  ]

30:                                               ; preds = %28
  store i16 0, ptr %2, align 2
  br label %31

31:                                               ; preds = %30, %28
  %32 = load i16, ptr %2, align 2
  ret i16 %32

33:                                               ; preds = %28
  unreachable
}

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef i64 @_ZNK5boost14dynamic_bitsetImSaImEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32)) #2 align 2

; Function Attrs: mustprogress uwtable
declare dso_local noundef zeroext i1 @_ZNK5boost14dynamic_bitsetImSaImEEixEm(ptr noundef nonnull align 8 dereferenceable(32), i64 noundef) #1 align 2

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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" }
attributes #2 = { inlinehint 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 #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++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"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"

; Function Attrs: mustprogress uwtable
define dso_local noundef zeroext i16 @_ZNK8regalloc20VirtualRegistersFile22find_free_range_at_endEv(ptr noundef nonnull align 8 dereferenceable(32) %0) local_unnamed_addr #0 align 2 {
  %2 = tail call noundef i64 @_ZNK5boost14dynamic_bitsetImSaImEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32) %0) #2
  %3 = and i64 %2, 4294967295
  br label %4

4:                                                ; preds = %6, %1
  %indvars.iv = phi i64 [ %indvars.iv.next, %6 ], [ %3, %1 ]
  %indvars.iv.next = add nsw i64 %indvars.iv, -1
  %5 = and i64 %indvars.iv.next, 2147483648
  %.not = icmp eq i64 %5, 0
  br i1 %.not, label %6, label %.loopexit

6:                                                ; preds = %4
  %7 = and i64 %indvars.iv.next, 2147483647
  %8 = tail call noundef zeroext i1 @_ZNK5boost14dynamic_bitsetImSaImEEixEm(ptr noundef nonnull align 8 dereferenceable(32) %0, i64 noundef %7)
  br i1 %8, label %4, label %9, !llvm.loop !5

9:                                                ; preds = %6
  %10 = trunc i64 %indvars.iv to i16
  br label %.loopexit

.loopexit:                                        ; preds = %4, %9
  %spec.select = phi i16 [ %10, %9 ], [ 0, %4 ]
  ret i16 %spec.select
}

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef i64 @_ZNK5boost14dynamic_bitsetImSaImEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(32)) local_unnamed_addr #1 align 2

; Function Attrs: mustprogress uwtable
declare dso_local noundef zeroext i1 @_ZNK5boost14dynamic_bitsetImSaImEEixEm(ptr noundef nonnull align 8 dereferenceable(32), i64 noundef) local_unnamed_addr #0 align 2

attributes #0 = { 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" }
attributes #1 = { inlinehint 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 #2 = { 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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


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