; LLVM IR from chachaxw/data-structure-and-algorithm :: leetcode/dynamic_programming/dp_climb_stairs.ll (ZN8Solution11climbStairsEi)

; 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"

%"class.std::vector" = type { %"struct.std::_Vector_base" }
%"struct.std::_Vector_base" = type { %"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl" }
%"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl" = type { %"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl_data" }
%"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl_data" = type { ptr, ptr, ptr }
%"class.std::allocator" = type { i8 }

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_ZN8Solution11climbStairsEi(ptr noundef nonnull align 1 dereferenceable(1) %0, i32 noundef %1) #0 align 2 personality ptr @__gxx_personality_v0 {
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca %"class.std::vector", align 8
  %7 = alloca %"class.std::allocator", align 1
  %8 = alloca ptr, align 8
  %9 = alloca i32, align 4
  %10 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  %11 = load ptr, ptr %4, align 8
  %12 = load i32, ptr %5, align 4, !tbaa !9
  %13 = icmp slt i32 %12, 2
  br i1 %13, label %14, label %16

14:                                               ; preds = %2
  %15 = load i32, ptr %5, align 4, !tbaa !9
  store i32 %15, ptr %3, align 4
  br label %55

16:                                               ; preds = %2
  call void @llvm.lifetime.start.p0(i64 24, ptr %6) #3
  %17 = load i32, ptr %5, align 4, !tbaa !9
  %18 = add nsw i32 %17, 1
  %19 = sext i32 %18 to i64
  call void @llvm.lifetime.start.p0(i64 1, ptr %7) #3
  call void @_ZNSaIiEC2Ev(ptr noundef nonnull align 1 dereferenceable(1) %7) #3
  invoke void @_ZNSt6vectorIiSaIiEEC2EmRKS0_(ptr noundef nonnull align 8 dereferenceable(24) %6, i64 noundef %19, ptr noundef nonnull align 1 dereferenceable(1) %7)
          to label %20 unwind label %28

20:                                               ; preds = %16
  call void @_ZNSt15__new_allocatorIiED2Ev(ptr noundef nonnull align 1 dereferenceable(1) %7) #3
  call void @llvm.lifetime.end.p0(i64 1, ptr %7) #3
  %21 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %6, i64 noundef 1) #3
  store i32 1, ptr %21, align 4, !tbaa !9
  %22 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %6, i64 noundef 2) #3
  store i32 2, ptr %22, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %10) #3
  store i32 3, ptr %10, align 4, !tbaa !9
  br label %23

23:                                               ; preds = %47, %20
  %24 = load i32, ptr %10, align 4, !tbaa !9
  %25 = load i32, ptr %5, align 4, !tbaa !9
  %26 = icmp sle i32 %24, %25
  br i1 %26, label %32, label %27

27:                                               ; preds = %23
  call void @llvm.lifetime.end.p0(i64 4, ptr %10) #3
  br label %50

28:                                               ; preds = %16
  %29 = landingpad { ptr, i32 }
          cleanup
  %30 = extractvalue { ptr, i32 } %29, 0
  store ptr %30, ptr %8, align 8
  %31 = extractvalue { ptr, i32 } %29, 1
  store i32 %31, ptr %9, align 4
  call void @_ZNSt15__new_allocatorIiED2Ev(ptr noundef nonnull align 1 dereferenceable(1) %7) #3
  call void @llvm.lifetime.end.p0(i64 1, ptr %7) #3
  call void @llvm.lifetime.end.p0(i64 24, ptr %6) #3
  br label %57

32:                                               ; preds = %23
  %33 = load i32, ptr %10, align 4, !tbaa !9
  %34 = sub nsw i32 %33, 1
  %35 = sext i32 %34 to i64
  %36 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %6, i64 noundef %35) #3
  %37 = load i32, ptr %36, align 4, !tbaa !9
  %38 = load i32, ptr %10, align 4, !tbaa !9
  %39 = sub nsw i32 %38, 2
  %40 = sext i32 %39 to i64
  %41 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %6, i64 noundef %40) #3
  %42 = load i32, ptr %41, align 4, !tbaa !9
  %43 = add nsw i32 %37, %42
  %44 = load i32, ptr %10, align 4, !tbaa !9
  %45 = sext i32 %44 to i64
  %46 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %6, i64 noundef %45) #3
  store i32 %43, ptr %46, align 4, !tbaa !9
  br label %47

47:                                               ; preds = %32
  %48 = load i32, ptr %10, align 4, !tbaa !9
  %49 = add nsw i32 %48, 1
  store i32 %49, ptr %10, align 4, !tbaa !9
  br label %23, !llvm.loop !11

50:                                               ; preds = %27
  %51 = load i32, ptr %5, align 4, !tbaa !9
  %52 = sext i32 %51 to i64
  %53 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %6, i64 noundef %52) #3
  %54 = load i32, ptr %53, align 4, !tbaa !9
  store i32 %54, ptr %3, align 4
  call void @_ZNSt6vectorIiSaIiEED2Ev(ptr noundef nonnull align 8 dereferenceable(24) %6) #3
  call void @llvm.lifetime.end.p0(i64 24, ptr %6) #3
  br label %55

55:                                               ; preds = %50, %14
  %56 = load i32, ptr %3, align 4
  ret i32 %56

57:                                               ; preds = %28
  %58 = load ptr, ptr %8, align 8
  %59 = load i32, ptr %9, align 4
  %60 = insertvalue { ptr, i32 } poison, ptr %58, 0
  %61 = insertvalue { ptr, i32 } %60, i32 %59, 1
  resume { ptr, i32 } %61
}

; 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 void @_ZNSaIiEC2Ev(ptr noundef nonnull align 1 dereferenceable(1)) unnamed_addr #2 align 2

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEEC2EmRKS0_(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef, ptr noundef nonnull align 1 dereferenceable(1)) unnamed_addr #0 align 2

declare i32 @__gxx_personality_v0(...)

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

; 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) #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEED2Ev(ptr noundef nonnull align 8 dereferenceable(24)) unnamed_addr #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZNSt15__new_allocatorIiED2Ev(ptr noundef nonnull align 1 dereferenceable(1)) unnamed_addr #2 align 2

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 = { 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 = !{!"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"

%"class.std::vector" = type { %"struct.std::_Vector_base" }
%"struct.std::_Vector_base" = type { %"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl" }
%"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl" = type { %"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl_data" }
%"struct.std::_Vector_base<int, std::allocator<int>>::_Vector_impl_data" = type { ptr, ptr, ptr }
%"class.std::allocator" = type { i8 }

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_ZN8Solution11climbStairsEi(ptr nocapture noundef nonnull readnone align 1 dereferenceable(1) %0, i32 noundef %1) local_unnamed_addr #0 align 2 personality ptr @__gxx_personality_v0 {
  %3 = alloca %"class.std::vector", align 8
  %4 = alloca %"class.std::allocator", align 1
  %5 = icmp slt i32 %1, 2
  br i1 %5, label %25, label %6

6:                                                ; preds = %2
  call void @llvm.lifetime.start.p0(i64 24, ptr nonnull %3) #3
  %7 = add nuw i32 %1, 1
  %8 = zext i32 %7 to i64
  call void @llvm.lifetime.start.p0(i64 1, ptr nonnull %4) #3
  call void @_ZNSaIiEC2Ev(ptr noundef nonnull align 1 dereferenceable(1) %4) #3
  invoke void @_ZNSt6vectorIiSaIiEEC2EmRKS0_(ptr noundef nonnull align 8 dereferenceable(24) %3, i64 noundef %8, ptr noundef nonnull align 1 dereferenceable(1) %4)
          to label %9 unwind label %15

9:                                                ; preds = %6
  call void @_ZNSt15__new_allocatorIiED2Ev(ptr noundef nonnull align 1 dereferenceable(1) %4) #3
  call void @llvm.lifetime.end.p0(i64 1, ptr nonnull %4) #3
  %10 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %3, i64 noundef 1) #3
  store i32 1, ptr %10, align 4, !tbaa !5
  %11 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %3, i64 noundef 2) #3
  store i32 2, ptr %11, align 4, !tbaa !5
  %.not15 = icmp eq i32 %1, 2
  br i1 %.not15, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %.lr.ph, %9
  %12 = zext nneg i32 %1 to i64
  %13 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %3, i64 noundef %12) #3
  %14 = load i32, ptr %13, align 4, !tbaa !5
  call void @_ZNSt6vectorIiSaIiEED2Ev(ptr noundef nonnull align 8 dereferenceable(24) %3) #3
  call void @llvm.lifetime.end.p0(i64 24, ptr nonnull %3) #3
  br label %25

15:                                               ; preds = %6
  %16 = landingpad { ptr, i32 }
          cleanup
  call void @_ZNSt15__new_allocatorIiED2Ev(ptr noundef nonnull align 1 dereferenceable(1) %4) #3
  call void @llvm.lifetime.end.p0(i64 1, ptr nonnull %4) #3
  call void @llvm.lifetime.end.p0(i64 24, ptr nonnull %3) #3
  resume { ptr, i32 } %16

.lr.ph:                                           ; preds = %9, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 3, %9 ]
  %17 = add nsw i64 %indvars.iv, -1
  %18 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %3, i64 noundef %17) #3
  %19 = load i32, ptr %18, align 4, !tbaa !5
  %20 = add nsw i64 %indvars.iv, -2
  %21 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %3, i64 noundef %20) #3
  %22 = load i32, ptr %21, align 4, !tbaa !5
  %23 = add nsw i32 %22, %19
  %24 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) %3, i64 noundef %indvars.iv) #3
  store i32 %23, ptr %24, align 4, !tbaa !5
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %exitcond.not = icmp eq i64 %indvars.iv.next, %8
  br i1 %exitcond.not, label %._crit_edge, label %.lr.ph, !llvm.loop !9

25:                                               ; preds = %2, %._crit_edge
  %.013 = phi i32 [ %14, %._crit_edge ], [ %1, %2 ]
  ret i32 %.013
}

; Function Attrs: mustprogress 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 void @_ZNSaIiEC2Ev(ptr noundef nonnull align 1 dereferenceable(1)) unnamed_addr #2 align 2

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEEC2EmRKS0_(ptr noundef nonnull align 8 dereferenceable(24), i64 noundef, ptr noundef nonnull align 1 dereferenceable(1)) unnamed_addr #0 align 2

declare i32 @__gxx_personality_v0(...)

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

; 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 #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZNSt6vectorIiSaIiEED2Ev(ptr noundef nonnull align 8 dereferenceable(24)) unnamed_addr #2 align 2

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_ZNSt15__new_allocatorIiED2Ev(ptr noundef nonnull align 1 dereferenceable(1)) unnamed_addr #2 align 2

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 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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 = !{!"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: EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass