; LLVM IR from Ayon-SSP/The-SDE-Prep :: 4]_SDE Sheet's/Strivers SDE Sheet/Day 03 [Arrays Part-III] (Count Reverse Pairs)

; 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 @_Z12reversePairsRSt6vectorIiSaIiEE(ptr noundef nonnull align 8 dereferenceable(24) %0) #0 {
  %2 = alloca ptr, align 8
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #2
  store i32 0, ptr %3, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #2
  store i32 0, ptr %4, align 4, !tbaa !9
  br label %7

7:                                                ; preds = %45, %1
  %8 = load i32, ptr %4, align 4, !tbaa !9
  %9 = sext i32 %8 to i64
  %10 = load ptr, ptr %2, align 8, !tbaa !5
  %11 = call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %10) #2
  %12 = icmp ult i64 %9, %11
  br i1 %12, label %14, label %13

13:                                               ; preds = %7
  store i32 2, ptr %5, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #2
  br label %48

14:                                               ; preds = %7
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  %15 = load i32, ptr %4, align 4, !tbaa !9
  %16 = add nsw i32 %15, 1
  store i32 %16, ptr %6, align 4, !tbaa !9
  br label %17

17:                                               ; preds = %41, %14
  %18 = load i32, ptr %6, align 4, !tbaa !9
  %19 = sext i32 %18 to i64
  %20 = load ptr, ptr %2, align 8, !tbaa !5
  %21 = call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %20) #2
  %22 = icmp ult i64 %19, %21
  br i1 %22, label %24, label %23

23:                                               ; preds = %17
  store i32 5, ptr %5, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  br label %44

24:                                               ; preds = %17
  %25 = load ptr, ptr %2, align 8, !tbaa !5
  %26 = load i32, ptr %4, align 4, !tbaa !9
  %27 = sext i32 %26 to i64
  %28 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %25, i64 noundef %27) #2
  %29 = load i32, ptr %28, align 4, !tbaa !9
  %30 = load ptr, ptr %2, align 8, !tbaa !5
  %31 = load i32, ptr %6, align 4, !tbaa !9
  %32 = sext i32 %31 to i64
  %33 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %30, i64 noundef %32) #2
  %34 = load i32, ptr %33, align 4, !tbaa !9
  %35 = mul nsw i32 2, %34
  %36 = icmp sgt i32 %29, %35
  br i1 %36, label %37, label %40

37:                                               ; preds = %24
  %38 = load i32, ptr %3, align 4, !tbaa !9
  %39 = add nsw i32 %38, 1
  store i32 %39, ptr %3, align 4, !tbaa !9
  br label %40

40:                                               ; preds = %37, %24
  br label %41

41:                                               ; preds = %40
  %42 = load i32, ptr %6, align 4, !tbaa !9
  %43 = add nsw i32 %42, 1
  store i32 %43, ptr %6, align 4, !tbaa !9
  br label %17, !llvm.loop !11

44:                                               ; preds = %23
  br label %45

45:                                               ; preds = %44
  %46 = load i32, ptr %4, align 4, !tbaa !9
  %47 = add nsw i32 %46, 1
  store i32 %47, ptr %4, align 4, !tbaa !9
  br label %7, !llvm.loop !13

48:                                               ; preds = %13
  %49 = load i32, ptr %3, align 4, !tbaa !9
  store i32 1, ptr %5, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #2
  ret i32 %49
}

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

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24)) #0 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef) #0 align 2

; 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"}
!13 = distinct !{!13, !12}


; 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
define dso_local noundef i32 @_Z12reversePairsRSt6vectorIiSaIiEE(ptr noundef nonnull align 8 dereferenceable(24) %0) local_unnamed_addr #0 {
  %2 = tail call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %0) #1
  %.not = icmp eq i64 %2, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph20

.loopexit:                                        ; preds = %.lr.ph, %.lr.ph20
  %.1.lcssa = phi i32 [ %.01318, %.lr.ph20 ], [ %spec.select, %.lr.ph ]
  %3 = tail call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %0) #1
  %4 = icmp ugt i64 %3, %indvars.iv.next26
  %indvars.iv.next = add i64 %indvars.iv, 1
  br i1 %4, label %.lr.ph20, label %._crit_edge, !llvm.loop !5

._crit_edge:                                      ; preds = %.loopexit, %1
  %.013.lcssa = phi i32 [ 0, %1 ], [ %.1.lcssa, %.loopexit ]
  ret i32 %.013.lcssa

.lr.ph20:                                         ; preds = %1, %.loopexit
  %indvars.iv25 = phi i64 [ %indvars.iv.next26, %.loopexit ], [ 0, %1 ]
  %indvars.iv = phi i64 [ %indvars.iv.next, %.loopexit ], [ 1, %1 ]
  %.01318 = phi i32 [ %.1.lcssa, %.loopexit ], [ 0, %1 ]
  %indvars.iv.next26 = add nuw nsw i64 %indvars.iv25, 1
  %5 = tail call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %0) #1
  %6 = icmp ugt i64 %5, %indvars.iv.next26
  br i1 %6, label %.lr.ph, label %.loopexit

.lr.ph:                                           ; preds = %.lr.ph20, %.lr.ph
  %indvars.iv22 = phi i64 [ %indvars.iv.next23, %.lr.ph ], [ %indvars.iv, %.lr.ph20 ]
  %.116 = phi i32 [ %spec.select, %.lr.ph ], [ %.01318, %.lr.ph20 ]
  %7 = tail call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %0, i64 noundef %indvars.iv25) #1
  %8 = load i32, ptr %7, align 4, !tbaa !7
  %9 = tail call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %0, i64 noundef %indvars.iv22) #1
  %10 = load i32, ptr %9, align 4, !tbaa !7
  %11 = shl nsw i32 %10, 1
  %12 = icmp sgt i32 %8, %11
  %13 = zext i1 %12 to i32
  %spec.select = add nsw i32 %.116, %13
  %indvars.iv.next23 = add nuw nsw i64 %indvars.iv22, 1
  %14 = tail call noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24) %0) #1
  %15 = icmp ugt i64 %14, %indvars.iv.next23
  br i1 %15, label %.lr.ph, label %.loopexit, !llvm.loop !11
}

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef i64 @_ZNKSt6vectorIiSaIiEE4sizeEv(ptr noundef nonnull align 8 dereferenceable(24)) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef) local_unnamed_addr #0 align 2

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 = { 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"}
!7 = !{!8, !8, i64 0}
!8 = !{!"int", !9, i64 0}
!9 = !{!"omnipotent char", !10, i64 0}
!10 = !{!"Simple C++ TBAA"}
!11 = distinct !{!11, !6}


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