; LLVM IR from VastoLorde95/Competitive-Programming :: Hackerrank/Codeagon 2017/Problem E/E3.ll (Z5dinicv)

; 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"

@n = external dso_local global i32, align 4
@s = external dso_local global i32, align 4
@ptr = external dso_local global [2100 x i32], align 16

; 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 nounwind uwtable
declare dso_local noundef zeroext i1 @_Z3bfsv() #1

; Function Attrs: nocallback nofree nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #2

; Function Attrs: mustprogress uwtable
declare dso_local noundef i32 @_Z3dfsii(i32 noundef, i32 noundef) #3

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z5dinicv() #3 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %1) #4
  store i32 0, ptr %1, align 4, !tbaa !5
  br label %4

4:                                                ; preds = %26, %0
  %5 = call noundef zeroext i1 @_Z3bfsv()
  br i1 %5, label %7, label %6

6:                                                ; preds = %4
  br label %27

7:                                                ; preds = %4
  %8 = load i32, ptr @n, align 4, !tbaa !5
  %9 = add nsw i32 %8, 1
  %10 = sext i32 %9 to i64
  %11 = mul i64 %10, 4
  call void @llvm.memset.p0.i64(ptr align 16 @ptr, i8 0, i64 %11, i1 false)
  br label %12

12:                                               ; preds = %25, %7
  br label %13

13:                                               ; preds = %12
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #4
  %14 = load i32, ptr @s, align 4, !tbaa !5
  %15 = call noundef i32 @_Z3dfsii(i32 noundef %14, i32 noundef 1000000000)
  store i32 %15, ptr %2, align 4, !tbaa !5
  %16 = load i32, ptr %2, align 4, !tbaa !5
  %17 = load i32, ptr %1, align 4, !tbaa !5
  %18 = add nsw i32 %17, %16
  store i32 %18, ptr %1, align 4, !tbaa !5
  %19 = load i32, ptr %2, align 4, !tbaa !5
  %20 = icmp ne i32 %19, 0
  br i1 %20, label %22, label %21

21:                                               ; preds = %13
  store i32 5, ptr %3, align 4
  br label %23

22:                                               ; preds = %13
  store i32 0, ptr %3, align 4
  br label %23

23:                                               ; preds = %22, %21
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #4
  %24 = load i32, ptr %3, align 4
  switch i32 %24, label %29 [
    i32 0, label %25
    i32 5, label %26
  ]

25:                                               ; preds = %23
  br label %12, !llvm.loop !9

26:                                               ; preds = %23
  br label %4, !llvm.loop !11

27:                                               ; preds = %6
  %28 = load i32, ptr %1, align 4, !tbaa !5
  store i32 1, ptr %3, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %1) #4
  ret i32 %28

29:                                               ; preds = %23
  unreachable
}

attributes #0 = { 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 = { nocallback nofree nounwind willreturn memory(argmem: write) }
attributes #3 = { 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 #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 = 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"

@n = external dso_local local_unnamed_addr global i32, align 4
@s = external dso_local local_unnamed_addr global i32, align 4
@ptr = external dso_local local_unnamed_addr global [2100 x i32], align 16

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef zeroext i1 @_Z3bfsv() local_unnamed_addr #0

; Function Attrs: mustprogress nocallback nofree nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #1

; Function Attrs: mustprogress uwtable
declare dso_local noundef i32 @_Z3dfsii(i32 noundef, i32 noundef) local_unnamed_addr #2

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_Z5dinicv() local_unnamed_addr #2 {
  %1 = tail call noundef zeroext i1 @_Z3bfsv()
  br i1 %1, label %.lr.ph, label %._crit_edge

.loopexit:                                        ; preds = %7
  %2 = tail call noundef zeroext i1 @_Z3bfsv()
  br i1 %2, label %.lr.ph, label %._crit_edge, !llvm.loop !5

.lr.ph:                                           ; preds = %0, %.loopexit
  %.056 = phi i32 [ %10, %.loopexit ], [ 0, %0 ]
  %3 = load i32, ptr @n, align 4, !tbaa !7
  %4 = add nsw i32 %3, 1
  %5 = sext i32 %4 to i64
  %6 = shl nsw i64 %5, 2
  tail call void @llvm.memset.p0.i64(ptr nonnull align 16 @ptr, i8 0, i64 %6, i1 false)
  br label %7

7:                                                ; preds = %7, %.lr.ph
  %.1 = phi i32 [ %.056, %.lr.ph ], [ %10, %7 ]
  %8 = load i32, ptr @s, align 4, !tbaa !7
  %9 = tail call noundef i32 @_Z3dfsii(i32 noundef %8, i32 noundef 1000000000)
  %10 = add nsw i32 %9, %.1
  %.not = icmp eq i32 %9, 0
  br i1 %.not, label %.loopexit, label %7, !llvm.loop !5

._crit_edge:                                      ; preds = %.loopexit, %0
  %.05.lcssa = phi i32 [ 0, %0 ], [ %10, %.loopexit ]
  ret i32 %.05.lcssa
}

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 = { mustprogress nocallback nofree nounwind willreturn memory(argmem: write) }
attributes #2 = { 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" }

!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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}
!7 = !{!8, !8, i64 0}
!8 = !{!"int", !9, i64 0}
!9 = !{!"omnipotent char", !10, i64 0}
!10 = !{!"Simple C++ TBAA"}


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