; LLVM IR from Muhammad-Magdi/problem-solving :: Dynamic Programming/Longest Common Subsequence.ll (Z3LCSii)

; 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::__cxx11::basic_string" = type { %"struct.std::__cxx11::basic_string<char>::_Alloc_hider", i64, %union.anon }
%"struct.std::__cxx11::basic_string<char>::_Alloc_hider" = type { ptr }
%union.anon = type { i64, [8 x i8] }

@mem = external dso_local global [2048 x [2048 x i32]], align 16
@n = external dso_local global i32, align 4
@m = external dso_local global i32, align 4
@_Z2s1B5cxx11 = external dso_local global %"class.std::__cxx11::basic_string", align 8
@_Z2s2B5cxx11 = external dso_local global %"class.std::__cxx11::basic_string", align 8

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z3LCSii(i32 noundef %0, i32 noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store i32 %0, ptr %4, align 4, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !5
  %8 = load i32, ptr %4, align 4, !tbaa !5
  %9 = load i32, ptr @n, align 4, !tbaa !5
  %10 = icmp eq i32 %8, %9
  br i1 %10, label %15, label %11

11:                                               ; preds = %2
  %12 = load i32, ptr %5, align 4, !tbaa !5
  %13 = load i32, ptr @m, align 4, !tbaa !5
  %14 = icmp eq i32 %12, %13
  br i1 %14, label %15, label %16

15:                                               ; preds = %11, %2
  store i32 0, ptr %3, align 4
  br label %76

16:                                               ; preds = %11
  %17 = load i32, ptr %4, align 4, !tbaa !5
  %18 = sext i32 %17 to i64
  %19 = getelementptr inbounds [2048 x [2048 x i32]], ptr @mem, i64 0, i64 %18
  %20 = load i32, ptr %5, align 4, !tbaa !5
  %21 = sext i32 %20 to i64
  %22 = getelementptr inbounds [2048 x i32], ptr %19, i64 0, i64 %21
  %23 = load i32, ptr %22, align 4, !tbaa !5
  %24 = xor i32 %23, -1
  %25 = icmp ne i32 %24, 0
  br i1 %25, label %26, label %34

26:                                               ; preds = %16
  %27 = load i32, ptr %4, align 4, !tbaa !5
  %28 = sext i32 %27 to i64
  %29 = getelementptr inbounds [2048 x [2048 x i32]], ptr @mem, i64 0, i64 %28
  %30 = load i32, ptr %5, align 4, !tbaa !5
  %31 = sext i32 %30 to i64
  %32 = getelementptr inbounds [2048 x i32], ptr %29, i64 0, i64 %31
  %33 = load i32, ptr %32, align 4, !tbaa !5
  store i32 %33, ptr %3, align 4
  br label %76

34:                                               ; preds = %16
  %35 = load i32, ptr %4, align 4, !tbaa !5
  %36 = sext i32 %35 to i64
  %37 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) @_Z2s1B5cxx11, i64 noundef %36)
  %38 = load i8, ptr %37, align 1, !tbaa !9
  %39 = sext i8 %38 to i32
  %40 = load i32, ptr %5, align 4, !tbaa !5
  %41 = sext i32 %40 to i64
  %42 = call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) @_Z2s2B5cxx11, i64 noundef %41)
  %43 = load i8, ptr %42, align 1, !tbaa !9
  %44 = sext i8 %43 to i32
  %45 = icmp eq i32 %39, %44
  br i1 %45, label %46, label %59

46:                                               ; preds = %34
  %47 = load i32, ptr %4, align 4, !tbaa !5
  %48 = add nsw i32 %47, 1
  %49 = load i32, ptr %5, align 4, !tbaa !5
  %50 = add nsw i32 %49, 1
  %51 = call noundef i32 @_Z3LCSii(i32 noundef %48, i32 noundef %50)
  %52 = add nsw i32 %51, 1
  %53 = load i32, ptr %4, align 4, !tbaa !5
  %54 = sext i32 %53 to i64
  %55 = getelementptr inbounds [2048 x [2048 x i32]], ptr @mem, i64 0, i64 %54
  %56 = load i32, ptr %5, align 4, !tbaa !5
  %57 = sext i32 %56 to i64
  %58 = getelementptr inbounds [2048 x i32], ptr %55, i64 0, i64 %57
  store i32 %52, ptr %58, align 4, !tbaa !5
  store i32 %52, ptr %3, align 4
  br label %76

59:                                               ; preds = %34
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #4
  %60 = load i32, ptr %4, align 4, !tbaa !5
  %61 = add nsw i32 %60, 1
  %62 = load i32, ptr %5, align 4, !tbaa !5
  %63 = call noundef i32 @_Z3LCSii(i32 noundef %61, i32 noundef %62)
  store i32 %63, ptr %6, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #4
  %64 = load i32, ptr %4, align 4, !tbaa !5
  %65 = load i32, ptr %5, align 4, !tbaa !5
  %66 = add nsw i32 %65, 1
  %67 = call noundef i32 @_Z3LCSii(i32 noundef %64, i32 noundef %66)
  store i32 %67, ptr %7, align 4, !tbaa !5
  %68 = 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) %7)
  %69 = load i32, ptr %68, align 4, !tbaa !5
  %70 = load i32, ptr %4, align 4, !tbaa !5
  %71 = sext i32 %70 to i64
  %72 = getelementptr inbounds [2048 x [2048 x i32]], ptr @mem, i64 0, i64 %71
  %73 = load i32, ptr %5, align 4, !tbaa !5
  %74 = sext i32 %73 to i64
  %75 = getelementptr inbounds [2048 x i32], ptr %72, i64 0, i64 %74
  store i32 %69, ptr %75, align 4, !tbaa !5
  store i32 %69, ptr %3, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #4
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #4
  br label %76

76:                                               ; preds = %59, %46, %26, %15
  %77 = load i32, ptr %3, align 4
  ret i32 %77
}

; Function Attrs: mustprogress nounwind uwtable
declare noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32), i64 noundef) #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)) #2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #3

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #3

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 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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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 = !{!7, !7, i64 0}


; 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::__cxx11::basic_string" = type { %"struct.std::__cxx11::basic_string<char>::_Alloc_hider", i64, %union.anon }
%"struct.std::__cxx11::basic_string<char>::_Alloc_hider" = type { ptr }
%union.anon = type { i64, [8 x i8] }

@mem = external dso_local local_unnamed_addr global [2048 x [2048 x i32]], align 16
@n = external dso_local local_unnamed_addr global i32, align 4
@m = external dso_local local_unnamed_addr global i32, align 4
@_Z2s1B5cxx11 = external dso_local global %"class.std::__cxx11::basic_string", align 8
@_Z2s2B5cxx11 = external dso_local global %"class.std::__cxx11::basic_string", align 8

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z3LCSii(i32 noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = load i32, ptr @n, align 4, !tbaa !5
  %6 = icmp eq i32 %5, %0
  %7 = load i32, ptr @m, align 4
  %8 = icmp eq i32 %7, %1
  %or.cond = select i1 %6, i1 true, i1 %8
  br i1 %or.cond, label %common.ret22, label %9

9:                                                ; preds = %2
  %10 = sext i32 %0 to i64
  %11 = sext i32 %1 to i64
  %12 = getelementptr inbounds [2048 x [2048 x i32]], ptr @mem, i64 0, i64 %10, i64 %11
  %13 = load i32, ptr %12, align 4, !tbaa !5
  %.not = icmp eq i32 %13, -1
  br i1 %.not, label %14, label %common.ret22

14:                                               ; preds = %9
  %15 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) @_Z2s1B5cxx11, i64 noundef %10)
  %16 = load i8, ptr %15, align 1, !tbaa !9
  %17 = tail call noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32) @_Z2s2B5cxx11, i64 noundef %11)
  %18 = load i8, ptr %17, align 1, !tbaa !9
  %19 = icmp eq i8 %16, %18
  br i1 %19, label %20, label %25

common.ret22:                                     ; preds = %9, %2, %25, %20
  %common.ret22.op = phi i32 [ %24, %20 ], [ %31, %25 ], [ 0, %2 ], [ %13, %9 ]
  ret i32 %common.ret22.op

20:                                               ; preds = %14
  %21 = add nsw i32 %0, 1
  %22 = add nsw i32 %1, 1
  %23 = tail call noundef i32 @_Z3LCSii(i32 noundef %21, i32 noundef %22)
  %24 = add nsw i32 %23, 1
  store i32 %24, ptr %12, align 4, !tbaa !5
  br label %common.ret22

25:                                               ; preds = %14
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %3) #3
  %26 = add nsw i32 %0, 1
  %27 = tail call noundef i32 @_Z3LCSii(i32 noundef %26, i32 noundef %1)
  store i32 %27, ptr %3, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %4) #3
  %28 = add nsw i32 %1, 1
  %29 = tail call noundef i32 @_Z3LCSii(i32 noundef %0, i32 noundef %28)
  store i32 %29, ptr %4, align 4, !tbaa !5
  %30 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3maxIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4) %3, ptr noundef nonnull align 4 dereferenceable(4) %4)
  %31 = load i32, ptr %30, align 4, !tbaa !5
  store i32 %31, ptr %12, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %4) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %3) #3
  br label %common.ret22
}

; Function Attrs: mustprogress nounwind uwtable
declare noundef nonnull align 1 dereferenceable(1) ptr @_ZNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEixEm(ptr noundef nonnull align 8 dereferenceable(32), i64 noundef) local_unnamed_addr #0 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 #1

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #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 = { 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 #2 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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 = !{!7, !7, i64 0}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass