; LLVM IR from Tudor67/Competitive-Programming :: Codeforces/#672#div2/B/B.ll (Z6getMSBRKiS0_)

; 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
define dso_local noundef i32 @_Z6getMSBRKiS0_(ptr noundef nonnull align 4 dereferenceable(4) %0, ptr noundef nonnull align 4 dereferenceable(4) %1) #0 {
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  store ptr %1, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  store i32 -1, ptr %5, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  %8 = load ptr, ptr %4, align 8, !tbaa !5
  %9 = load i32, ptr %8, align 4, !tbaa !9
  store i32 %9, ptr %6, align 4, !tbaa !9
  br label %10

10:                                               ; preds = %24, %2
  %11 = load i32, ptr %6, align 4, !tbaa !9
  %12 = icmp sge i32 %11, 0
  br i1 %12, label %14, label %13

13:                                               ; preds = %10
  store i32 2, ptr %7, align 4
  br label %27

14:                                               ; preds = %10
  %15 = load ptr, ptr %3, align 8, !tbaa !5
  %16 = load i32, ptr %15, align 4, !tbaa !9
  %17 = load i32, ptr %6, align 4, !tbaa !9
  %18 = ashr i32 %16, %17
  %19 = and i32 %18, 1
  %20 = icmp ne i32 %19, 0
  br i1 %20, label %21, label %23

21:                                               ; preds = %14
  %22 = load i32, ptr %6, align 4, !tbaa !9
  store i32 %22, ptr %5, align 4, !tbaa !9
  store i32 2, ptr %7, align 4
  br label %27

23:                                               ; preds = %14
  br label %24

24:                                               ; preds = %23
  %25 = load i32, ptr %6, align 4, !tbaa !9
  %26 = add nsw i32 %25, -1
  store i32 %26, ptr %6, align 4, !tbaa !9
  br label %10, !llvm.loop !11

27:                                               ; preds = %21, %13
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  br label %28

28:                                               ; preds = %27
  %29 = load i32, ptr %5, align 4, !tbaa !9
  store i32 1, ptr %7, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  ret i32 %29
}

; 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

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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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 = !{!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 nofree norecurse nosync nounwind willreturn memory(argmem: read) uwtable
define dso_local noundef range(i32 -1, -2147483648) i32 @_Z6getMSBRKiS0_(ptr nocapture noundef nonnull readonly align 4 dereferenceable(4) %0, ptr nocapture noundef nonnull readonly align 4 dereferenceable(4) %1) local_unnamed_addr #0 {
  %3 = load i32, ptr %1, align 4, !tbaa !5
  %4 = icmp sgt i32 %3, -1
  br i1 %4, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %2
  %5 = load i32, ptr %0, align 4, !tbaa !5
  br label %6

6:                                                ; preds = %.lr.ph, %9
  %.07 = phi i32 [ %3, %.lr.ph ], [ %10, %9 ]
  %7 = shl nuw i32 1, %.07
  %8 = and i32 %5, %7
  %.not = icmp eq i32 %8, 0
  br i1 %.not, label %9, label %._crit_edge

9:                                                ; preds = %6
  %10 = add nsw i32 %.07, -1
  %11 = icmp sgt i32 %.07, 0
  br i1 %11, label %6, label %._crit_edge, !llvm.loop !9

._crit_edge:                                      ; preds = %9, %6, %2
  %.06 = phi i32 [ -1, %2 ], [ %.07, %6 ], [ -1, %9 ]
  ret i32 %.06
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: read) 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


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