; LLVM IR from Tunghohin/Competitive_Coding :: Luogu/p4866.ll (Z10get_prefixxPKx)

; 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 i64 @_Z7low_bitx(i64 noundef) #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i64 @_Z10get_prefixxPKx(i64 noundef %0, ptr noundef %1) #0 {
  %3 = alloca i64, align 8
  %4 = alloca ptr, align 8
  %5 = alloca i64, align 8
  store i64 %0, ptr %3, align 8, !tbaa !5
  store ptr %1, ptr %4, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #2
  store i64 0, ptr %5, align 8, !tbaa !5
  br label %6

6:                                                ; preds = %9, %2
  %7 = load i64, ptr %3, align 8, !tbaa !5
  %8 = icmp sge i64 %7, 1
  br i1 %8, label %9, label %20

9:                                                ; preds = %6
  %10 = load ptr, ptr %4, align 8, !tbaa !9
  %11 = load i64, ptr %3, align 8, !tbaa !5
  %12 = getelementptr inbounds i64, ptr %10, i64 %11
  %13 = load i64, ptr %12, align 8, !tbaa !5
  %14 = load i64, ptr %5, align 8, !tbaa !5
  %15 = add nsw i64 %14, %13
  store i64 %15, ptr %5, align 8, !tbaa !5
  %16 = load i64, ptr %3, align 8, !tbaa !5
  %17 = call noundef i64 @_Z7low_bitx(i64 noundef %16)
  %18 = load i64, ptr %3, align 8, !tbaa !5
  %19 = sub nsw i64 %18, %17
  store i64 %19, ptr %3, align 8, !tbaa !5
  br label %6, !llvm.loop !11

20:                                               ; preds = %6
  %21 = load i64, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #2
  ret i64 %21
}

; 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 = !{!"long long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !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 nounwind uwtable
declare dso_local noundef i64 @_Z7low_bitx(i64 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i64 @_Z10get_prefixxPKx(i64 noundef %0, ptr nocapture noundef readonly %1) local_unnamed_addr #0 {
  %3 = icmp sgt i64 %0, 0
  br i1 %3, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %2, %.lr.ph
  %.08 = phi i64 [ %6, %.lr.ph ], [ 0, %2 ]
  %.067 = phi i64 [ %8, %.lr.ph ], [ %0, %2 ]
  %4 = getelementptr inbounds i64, ptr %1, i64 %.067
  %5 = load i64, ptr %4, align 8, !tbaa !5
  %6 = add nsw i64 %5, %.08
  %7 = tail call noundef i64 @_Z7low_bitx(i64 noundef %.067)
  %8 = sub nsw i64 %.067, %7
  %9 = icmp sgt i64 %8, 0
  br i1 %9, label %.lr.ph, label %._crit_edge, !llvm.loop !9

._crit_edge:                                      ; preds = %.lr.ph, %2
  %.0.lcssa = phi i64 [ 0, %2 ], [ %6, %.lr.ph ]
  ret i64 %.0.lcssa
}

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)"}
!5 = !{!6, !6, i64 0}
!6 = !{!"long long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass