; LLVM IR from brpapa/algorithms :: notebook/dynamic-programming/rod-cutting.ll (Z2dpi)

; 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 }

@prices = external dso_local global %"class.std::vector", align 8
@memo = external dso_local global %"class.std::vector", align 8

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z2dpi(i32 noundef %0) #1 {
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  %8 = load i32, ptr %3, align 4, !tbaa !5
  %9 = icmp eq i32 %8, 0
  br i1 %9, label %10, label %11

10:                                               ; preds = %1
  store i32 0, ptr %2, align 4
  br label %50

11:                                               ; preds = %1
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  %12 = load i32, ptr %3, align 4, !tbaa !5
  %13 = sext i32 %12 to i64
  %14 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) @memo, i64 noundef %13) #4
  store ptr %14, ptr %4, align 8, !tbaa !9
  %15 = load ptr, ptr %4, align 8, !tbaa !9
  %16 = load i32, ptr %15, align 4, !tbaa !5
  %17 = icmp ne i32 %16, -1
  br i1 %17, label %18, label %21

18:                                               ; preds = %11
  %19 = load ptr, ptr %4, align 8, !tbaa !9
  %20 = load i32, ptr %19, align 4, !tbaa !5
  store i32 %20, ptr %2, align 4
  store i32 1, ptr %5, align 4
  br label %49

21:                                               ; preds = %11
  %22 = load ptr, ptr %4, align 8, !tbaa !9
  store i32 -1073741824, ptr %22, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #4
  store i32 0, ptr %6, align 4, !tbaa !5
  br label %23

23:                                               ; preds = %43, %21
  %24 = load i32, ptr %6, align 4, !tbaa !5
  %25 = load i32, ptr %3, align 4, !tbaa !5
  %26 = icmp slt i32 %24, %25
  br i1 %26, label %28, label %27

27:                                               ; preds = %23
  store i32 2, ptr %5, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #4
  br label %46

28:                                               ; preds = %23
  %29 = load ptr, ptr %4, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #4
  %30 = load i32, ptr %6, align 4, !tbaa !5
  %31 = sext i32 %30 to i64
  %32 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) @prices, i64 noundef %31) #4
  %33 = load i32, ptr %32, align 4, !tbaa !5
  %34 = load i32, ptr %3, align 4, !tbaa !5
  %35 = load i32, ptr %6, align 4, !tbaa !5
  %36 = add nsw i32 %35, 1
  %37 = sub nsw i32 %34, %36
  %38 = call noundef i32 @_Z2dpi(i32 noundef %37)
  %39 = add nsw i32 %33, %38
  store i32 %39, ptr %7, align 4, !tbaa !5
  %40 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3maxIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4) %29, ptr noundef nonnull align 4 dereferenceable(4) %7)
  %41 = load i32, ptr %40, align 4, !tbaa !5
  %42 = load ptr, ptr %4, align 8, !tbaa !9
  store i32 %41, ptr %42, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #4
  br label %43

43:                                               ; preds = %28
  %44 = load i32, ptr %6, align 4, !tbaa !5
  %45 = add nsw i32 %44, 1
  store i32 %45, ptr %6, align 4, !tbaa !5
  br label %23, !llvm.loop !11

46:                                               ; preds = %27
  %47 = load ptr, ptr %4, align 8, !tbaa !9
  %48 = load i32, ptr %47, align 4, !tbaa !5
  store i32 %48, ptr %2, align 4
  store i32 1, ptr %5, align 4
  br label %49

49:                                               ; preds = %46, %18
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  br label %50

50:                                               ; preds = %49, %10
  %51 = load i32, ptr %2, align 4
  ret i32 %51
}

; 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: inlinehint mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3maxIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4), ptr noundef nonnull align 4 dereferenceable(4)) #3

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #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 = { 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 #4 = { 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 = !{!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"

%"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 }

@prices = external dso_local global %"class.std::vector", align 8
@memo = external dso_local global %"class.std::vector", align 8

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z2dpi(i32 noundef %0) local_unnamed_addr #1 {
  %2 = alloca i32, align 4
  %3 = icmp eq i32 %0, 0
  br i1 %3, label %._crit_edge, label %4

4:                                                ; preds = %1
  %5 = sext i32 %0 to i64
  %6 = tail call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) @memo, i64 noundef %5) #3
  %7 = load i32, ptr %6, align 4, !tbaa !5
  %.not = icmp eq i32 %7, -1
  br i1 %.not, label %8, label %._crit_edge

8:                                                ; preds = %4
  store i32 -1073741824, ptr %6, align 4, !tbaa !5
  %9 = icmp sgt i32 %0, 0
  br i1 %9, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %8
  %wide.trip.count = zext nneg i32 %0 to i64
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %.lr.ph
  %indvars.iv = phi i64 [ 0, %.lr.ph.preheader ], [ %indvars.iv.next, %.lr.ph ]
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #3
  %10 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZNSt6vectorIiSaIiEEixEm(ptr noundef nonnull align 8 dereferenceable(24) @prices, i64 noundef %indvars.iv) #3
  %11 = load i32, ptr %10, align 4, !tbaa !5
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %12 = trunc i64 %indvars.iv.next to i32
  %13 = sub i32 %0, %12
  %14 = call noundef i32 @_Z2dpi(i32 noundef %13)
  %15 = add nsw i32 %14, %11
  store i32 %15, ptr %2, align 4, !tbaa !5
  %16 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3maxIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4) %6, ptr noundef nonnull align 4 dereferenceable(4) %2)
  %17 = load i32, ptr %16, align 4, !tbaa !5
  store i32 %17, ptr %6, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #3
  %exitcond.not = icmp eq i64 %indvars.iv.next, %wide.trip.count
  br i1 %exitcond.not, label %._crit_edge, label %.lr.ph, !llvm.loop !9

._crit_edge:                                      ; preds = %.lr.ph, %8, %4, %1
  %.1 = phi i32 [ 0, %1 ], [ %7, %4 ], [ -1073741824, %8 ], [ %17, %.lr.ph ]
  ret i32 %.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 #1 align 2

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3maxIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #2

attributes #0 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #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 = !{!"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,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass