; LLVM IR from lzyrapx/Competitive-Programming :: HDUOJ/2175（汉诺塔）.ll (Z3dfsxx)

; 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 uwtable
define dso_local noundef i64 @_Z3dfsxx(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
  %7 = alloca i32, align 4
  store i64 %0, ptr %4, align 8, !tbaa !5
  store i64 %1, ptr %5, align 8, !tbaa !5
  %8 = load i64, ptr %4, align 8, !tbaa !5
  %9 = icmp eq i64 %8, 1
  br i1 %9, label %10, label %14

10:                                               ; preds = %2
  %11 = load i64, ptr %5, align 8, !tbaa !5
  %12 = icmp eq i64 %11, 1
  br i1 %12, label %13, label %14

13:                                               ; preds = %10
  store i64 1, ptr %3, align 8
  br label %41

14:                                               ; preds = %10, %2
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #3
  %15 = load i64, ptr %4, align 8, !tbaa !5
  %16 = sub nsw i64 %15, 1
  %17 = call noundef double @_ZSt3powIixEN9__gnu_cxx9__promoteIDTplcvNS1_IT_Xsr3std12__is_integerIS2_EE7__valueEE6__typeELi0EcvNS1_IT0_Xsr3std12__is_integerIS5_EE7__valueEE6__typeELi0EEXsr3std12__is_integerIS8_EE7__valueEE6__typeES2_S5_(i32 noundef 2, i64 noundef %16)
  %18 = fptosi double %17 to i64
  store i64 %18, ptr %6, align 8, !tbaa !5
  %19 = load i64, ptr %5, align 8, !tbaa !5
  %20 = load i64, ptr %6, align 8, !tbaa !5
  %21 = icmp eq i64 %19, %20
  br i1 %21, label %22, label %24

22:                                               ; preds = %14
  %23 = load i64, ptr %4, align 8, !tbaa !5
  store i64 %23, ptr %3, align 8
  store i32 1, ptr %7, align 4
  br label %40

24:                                               ; preds = %14
  %25 = load i64, ptr %5, align 8, !tbaa !5
  %26 = load i64, ptr %6, align 8, !tbaa !5
  %27 = icmp sgt i64 %25, %26
  br i1 %27, label %28, label %35

28:                                               ; preds = %24
  %29 = load i64, ptr %4, align 8, !tbaa !5
  %30 = sub nsw i64 %29, 1
  %31 = load i64, ptr %5, align 8, !tbaa !5
  %32 = load i64, ptr %6, align 8, !tbaa !5
  %33 = sub nsw i64 %31, %32
  %34 = call noundef i64 @_Z3dfsxx(i64 noundef %30, i64 noundef %33)
  store i64 %34, ptr %3, align 8
  store i32 1, ptr %7, align 4
  br label %40

35:                                               ; preds = %24
  %36 = load i64, ptr %4, align 8, !tbaa !5
  %37 = sub nsw i64 %36, 1
  %38 = load i64, ptr %5, align 8, !tbaa !5
  %39 = call noundef i64 @_Z3dfsxx(i64 noundef %37, i64 noundef %38)
  store i64 %39, ptr %3, align 8
  store i32 1, ptr %7, align 4
  br label %40

40:                                               ; preds = %35, %28, %22
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #3
  br label %41

41:                                               ; preds = %40, %13
  %42 = load i64, ptr %3, align 8
  ret i64 %42
}

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

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef double @_ZSt3powIixEN9__gnu_cxx9__promoteIDTplcvNS1_IT_Xsr3std12__is_integerIS2_EE7__valueEE6__typeELi0EcvNS1_IT0_Xsr3std12__is_integerIS5_EE7__valueEE6__typeELi0EEXsr3std12__is_integerIS8_EE7__valueEE6__typeES2_S5_(i32 noundef, i64 noundef) #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 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 = { 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 = !{!"long long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}


; 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 i64 @_Z3dfsxx(i64 noundef %0, i64 noundef %1) local_unnamed_addr #0 {
  %3 = icmp eq i64 %0, 1
  %4 = icmp eq i64 %1, 1
  %or.cond18 = and i1 %3, %4
  br i1 %or.cond18, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %2, %tailrecurse
  %.tr1720 = phi i64 [ %spec.select, %tailrecurse ], [ %1, %2 ]
  %.tr19 = phi i64 [ %5, %tailrecurse ], [ %0, %2 ]
  %5 = add nsw i64 %.tr19, -1
  %6 = tail call noundef double @_ZSt3powIixEN9__gnu_cxx9__promoteIDTplcvNS1_IT_Xsr3std12__is_integerIS2_EE7__valueEE6__typeELi0EcvNS1_IT0_Xsr3std12__is_integerIS5_EE7__valueEE6__typeELi0EEXsr3std12__is_integerIS8_EE7__valueEE6__typeES2_S5_(i32 noundef 2, i64 noundef %5)
  %7 = fptosi double %6 to i64
  %8 = icmp eq i64 %.tr1720, %7
  br i1 %8, label %._crit_edge, label %tailrecurse

tailrecurse:                                      ; preds = %.lr.ph
  %9 = icmp sgt i64 %.tr1720, %7
  %10 = select i1 %9, i64 %7, i64 0
  %spec.select = sub nsw i64 %.tr1720, %10
  %11 = icmp eq i64 %5, 1
  %12 = icmp eq i64 %spec.select, 1
  %or.cond = and i1 %11, %12
  br i1 %or.cond, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %tailrecurse, %.lr.ph, %2
  %.1 = phi i64 [ 1, %2 ], [ %.tr19, %.lr.ph ], [ 1, %tailrecurse ]
  ret i64 %.1
}

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef double @_ZSt3powIixEN9__gnu_cxx9__promoteIDTplcvNS1_IT_Xsr3std12__is_integerIS2_EE7__valueEE6__typeELi0EcvNS1_IT0_Xsr3std12__is_integerIS5_EE7__valueEE6__typeELi0EEXsr3std12__is_integerIS8_EE7__valueEE6__typeES2_S5_(i32 noundef, i64 noundef) local_unnamed_addr #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 = { 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" }

!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)"}


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