; LLVM IR from ritikbanger/Hacktoberfest2022-DSA :: 04. Arrays (Maximum Subarray Sum (via Kadane's algorithm))

; 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::basic_istream" = type { ptr, i64, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }

@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [23 x i8], align 1

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca i64, align 8
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #6
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #6
  %8 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %2)
  %9 = load i32, ptr %2, align 4, !tbaa !5
  %10 = zext i32 %9 to i64
  %11 = call ptr @llvm.stacksave.p0()
  store ptr %11, ptr %4, align 8
  %12 = alloca i32, i64 %10, align 16
  store i64 %10, ptr %5, align 8
  store i32 0, ptr %3, align 4, !tbaa !5
  br label %13

13:                                               ; preds = %22, %0
  %14 = load i32, ptr %3, align 4, !tbaa !5
  %15 = load i32, ptr %2, align 4, !tbaa !5
  %16 = icmp slt i32 %14, %15
  br i1 %16, label %17, label %25

17:                                               ; preds = %13
  %18 = load i32, ptr %3, align 4, !tbaa !5
  %19 = sext i32 %18 to i64
  %20 = getelementptr inbounds i32, ptr %12, i64 %19
  %21 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %20)
  br label %22

22:                                               ; preds = %17
  %23 = load i32, ptr %3, align 4, !tbaa !5
  %24 = add nsw i32 %23, 1
  store i32 %24, ptr %3, align 4, !tbaa !5
  br label %13, !llvm.loop !9

25:                                               ; preds = %13
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #6
  store i32 0, ptr %6, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #6
  store i32 -2147483648, ptr %7, align 4, !tbaa !5
  store i32 0, ptr %3, align 4, !tbaa !5
  br label %26

26:                                               ; preds = %48, %25
  %27 = load i32, ptr %3, align 4, !tbaa !5
  %28 = load i32, ptr %2, align 4, !tbaa !5
  %29 = icmp slt i32 %27, %28
  br i1 %29, label %30, label %51

30:                                               ; preds = %26
  %31 = load i32, ptr %6, align 4, !tbaa !5
  %32 = load i32, ptr %3, align 4, !tbaa !5
  %33 = sext i32 %32 to i64
  %34 = getelementptr inbounds i32, ptr %12, i64 %33
  %35 = load i32, ptr %34, align 4, !tbaa !5
  %36 = add nsw i32 %31, %35
  store i32 %36, ptr %6, align 4, !tbaa !5
  %37 = load i32, ptr %6, align 4, !tbaa !5
  %38 = icmp sge i32 %37, 0
  br i1 %38, label %39, label %42

39:                                               ; preds = %30
  %40 = call noundef nonnull align 4 dereferenceable(4) ptr @_ZSt3maxIiERKT_S2_S2_(ptr noundef nonnull align 4 dereferenceable(4) %7, ptr noundef nonnull align 4 dereferenceable(4) %6)
  %41 = load i32, ptr %40, align 4, !tbaa !5
  store i32 %41, ptr %7, align 4, !tbaa !5
  br label %47

42:                                               ; preds = %30
  %43 = load i32, ptr %6, align 4, !tbaa !5
  %44 = icmp slt i32 %43, 0
  br i1 %44, label %45, label %46

45:                                               ; preds = %42
  store i32 0, ptr %6, align 4, !tbaa !5
  br label %46

46:                                               ; preds = %45, %42
  br label %47

47:                                               ; preds = %46, %39
  br label %48

48:                                               ; preds = %47
  %49 = load i32, ptr %3, align 4, !tbaa !5
  %50 = add nsw i32 %49, 1
  store i32 %50, ptr %3, align 4, !tbaa !5
  br label %26, !llvm.loop !11

51:                                               ; preds = %26
  %52 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef @.str)
  %53 = load i32, ptr %7, align 4, !tbaa !5
  %54 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) %52, i32 noundef %53)
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #6
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #6
  %55 = load ptr, ptr %4, align 8
  call void @llvm.stackrestore.p0(ptr %55)
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #6
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #6
  %56 = load i32, ptr %1, align 4
  ret i32 %56
}

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

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) #2

; Function Attrs: nocallback nofree nosync nounwind willreturn
declare ptr @llvm.stacksave.p0() #3

; 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)) #4

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #5

declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) #2

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

; Function Attrs: nocallback nofree nosync nounwind willreturn
declare void @llvm.stackrestore.p0(ptr) #3

attributes #0 = { mustprogress norecurse 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 = { "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 }
attributes #4 = { 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 #5 = { inlinehint 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 #6 = { 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"}
!11 = distinct !{!11, !10}


; 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::basic_istream" = type { ptr, i64, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }

@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8
@.str = external hidden unnamed_addr constant [23 x i8], align 1

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #6
  %4 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %1)
  %5 = load i32, ptr %1, align 4, !tbaa !5
  %6 = zext i32 %5 to i64
  %7 = call ptr @llvm.stacksave.p0()
  %8 = alloca i32, i64 %6, align 16
  %9 = load i32, ptr %1, align 4, !tbaa !5
  %10 = icmp sgt i32 %9, 0
  br i1 %10, label %.lr.ph, label %._crit_edge.thread

._crit_edge.thread:                               ; preds = %0
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #6
  store i32 0, ptr %2, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %3) #6
  store i32 -2147483648, ptr %3, align 4, !tbaa !5
  br label %._crit_edge11

.lr.ph:                                           ; preds = %0, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %0 ]
  %11 = getelementptr inbounds i32, ptr %8, i64 %indvars.iv
  %12 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %11)
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %13 = load i32, ptr %1, align 4, !tbaa !5
  %14 = sext i32 %13 to i64
  %15 = icmp slt i64 %indvars.iv.next, %14
  br i1 %15, label %.lr.ph, label %._crit_edge, !llvm.loop !9

._crit_edge:                                      ; preds = %.lr.ph
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #6
  store i32 0, ptr %2, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %3) #6
  store i32 -2147483648, ptr %3, align 4, !tbaa !5
  %16 = icmp sgt i32 %13, 0
  br i1 %16, label %.lr.ph10, label %._crit_edge11

.lr.ph10:                                         ; preds = %._crit_edge, %27
  %17 = phi i32 [ %28, %27 ], [ %13, %._crit_edge ]
  %indvars.iv13 = phi i64 [ %indvars.iv.next14, %27 ], [ 0, %._crit_edge ]
  %18 = load i32, ptr %2, align 4, !tbaa !5
  %19 = getelementptr inbounds i32, ptr %8, i64 %indvars.iv13
  %20 = load i32, ptr %19, align 4, !tbaa !5
  %21 = add nsw i32 %20, %18
  store i32 %21, ptr %2, align 4, !tbaa !5
  %22 = icmp sgt i32 %21, -1
  br i1 %22, label %23, label %26

23:                                               ; preds = %.lr.ph10
  %24 = 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) %2)
  %25 = load i32, ptr %24, align 4, !tbaa !5
  store i32 %25, ptr %3, align 4, !tbaa !5
  %.pre = load i32, ptr %1, align 4, !tbaa !5
  br label %27

26:                                               ; preds = %.lr.ph10
  store i32 0, ptr %2, align 4, !tbaa !5
  br label %27

27:                                               ; preds = %23, %26
  %28 = phi i32 [ %.pre, %23 ], [ %17, %26 ]
  %indvars.iv.next14 = add nuw nsw i64 %indvars.iv13, 1
  %29 = sext i32 %28 to i64
  %30 = icmp slt i64 %indvars.iv.next14, %29
  br i1 %30, label %.lr.ph10, label %._crit_edge11, !llvm.loop !11

._crit_edge11:                                    ; preds = %27, %._crit_edge.thread, %._crit_edge
  %31 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, ptr noundef nonnull @.str)
  %32 = load i32, ptr %3, align 4, !tbaa !5
  %33 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) %31, i32 noundef %32)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %3) #6
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #6
  call void @llvm.stackrestore.p0(ptr %7)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #6
  ret i32 0
}

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

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn
declare ptr @llvm.stacksave.p0() #3

; 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 #4

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #5

declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) local_unnamed_addr #2

; 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 nocallback nofree nosync nounwind willreturn
declare void @llvm.stackrestore.p0(ptr) #3

attributes #0 = { mustprogress norecurse 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 = { "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 = { mustprogress nocallback nofree nosync nounwind willreturn }
attributes #4 = { 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 #5 = { inlinehint 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 #6 = { 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"}
!11 = distinct !{!11, !10}


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