; LLVM IR from kazunetakahashi/atcoder :: 2020/0613_tokiomarine2020/E.ll (Z4combxx)

; 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 i64 @_Z4combxx(i64 noundef %0, i64 noundef %1) #0 {
  %3 = alloca i64, align 8
  %4 = alloca i64, align 8
  %5 = alloca i64, align 8
  %6 = alloca i64, align 8
  store i64 %0, ptr %3, align 8, !tbaa !5
  store i64 %1, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #2
  store i64 1, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #2
  store i64 0, ptr %6, align 8, !tbaa !5
  br label %7

7:                                                ; preds = %22, %2
  %8 = load i64, ptr %6, align 8, !tbaa !5
  %9 = load i64, ptr %4, align 8, !tbaa !5
  %10 = icmp slt i64 %8, %9
  br i1 %10, label %12, label %11

11:                                               ; preds = %7
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #2
  br label %25

12:                                               ; preds = %7
  %13 = load i64, ptr %3, align 8, !tbaa !5
  %14 = load i64, ptr %6, align 8, !tbaa !5
  %15 = sub nsw i64 %13, %14
  %16 = load i64, ptr %5, align 8, !tbaa !5
  %17 = mul nsw i64 %16, %15
  store i64 %17, ptr %5, align 8, !tbaa !5
  %18 = load i64, ptr %6, align 8, !tbaa !5
  %19 = add nsw i64 %18, 1
  %20 = load i64, ptr %5, align 8, !tbaa !5
  %21 = sdiv i64 %20, %19
  store i64 %21, ptr %5, align 8, !tbaa !5
  br label %22

22:                                               ; preds = %12
  %23 = load i64, ptr %6, align 8, !tbaa !5
  %24 = add nsw i64 %23, 1
  store i64 %24, ptr %6, align 8, !tbaa !5
  br label %7, !llvm.loop !9

25:                                               ; preds = %11
  %26 = load i64, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #2
  ret i64 %26
}

; 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 = distinct !{!9, !10}
!10 = !{!"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(none) uwtable
define dso_local noundef i64 @_Z4combxx(i64 noundef %0, i64 noundef %1) local_unnamed_addr #0 {
  %3 = icmp sgt i64 %1, 0
  br i1 %3, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %2
  %xtraiter = and i64 %1, 1
  %4 = icmp eq i64 %1, 1
  br i1 %4, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph.preheader.new

.lr.ph.preheader.new:                             ; preds = %.lr.ph.preheader
  %unroll_iter = and i64 %1, 9223372036854775806
  br label %.lr.ph

._crit_edge.loopexit.unr-lcssa:                   ; preds = %.lr.ph, %.lr.ph.preheader
  %.lcssa.ph = phi i64 [ poison, %.lr.ph.preheader ], [ %16, %.lr.ph ]
  %.011.unr = phi i64 [ 0, %.lr.ph.preheader ], [ %15, %.lr.ph ]
  %.0910.unr = phi i64 [ 1, %.lr.ph.preheader ], [ %16, %.lr.ph ]
  %lcmp.mod.not = icmp eq i64 %xtraiter, 0
  br i1 %lcmp.mod.not, label %._crit_edge, label %.lr.ph.epil

.lr.ph.epil:                                      ; preds = %._crit_edge.loopexit.unr-lcssa
  %5 = sub nsw i64 %0, %.011.unr
  %6 = mul nsw i64 %5, %.0910.unr
  %7 = add nuw nsw i64 %.011.unr, 1
  %8 = sdiv i64 %6, %7
  br label %._crit_edge

._crit_edge:                                      ; preds = %.lr.ph.epil, %._crit_edge.loopexit.unr-lcssa, %2
  %.09.lcssa = phi i64 [ 1, %2 ], [ %.lcssa.ph, %._crit_edge.loopexit.unr-lcssa ], [ %8, %.lr.ph.epil ]
  ret i64 %.09.lcssa

.lr.ph:                                           ; preds = %.lr.ph, %.lr.ph.preheader.new
  %.011 = phi i64 [ 0, %.lr.ph.preheader.new ], [ %15, %.lr.ph ]
  %.0910 = phi i64 [ 1, %.lr.ph.preheader.new ], [ %16, %.lr.ph ]
  %niter = phi i64 [ 0, %.lr.ph.preheader.new ], [ %niter.next.1, %.lr.ph ]
  %9 = sub nsw i64 %0, %.011
  %10 = mul nsw i64 %9, %.0910
  %11 = or disjoint i64 %.011, 1
  %12 = sdiv i64 %10, %11
  %13 = sub nsw i64 %0, %11
  %14 = mul nsw i64 %13, %12
  %15 = add nuw nsw i64 %.011, 2
  %16 = sdiv i64 %14, %15
  %niter.next.1 = add i64 %niter, 2
  %niter.ncmp.1 = icmp eq i64 %niter.next.1, %unroll_iter
  br i1 %niter.ncmp.1, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph, !llvm.loop !5
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(none) 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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


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