; LLVM IR from upupming/algorithm :: kick-start/2020/2020A-C.ll (Z5solvev)

; 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"

@k = external dso_local global i32, align 4
@max_diff = external dso_local global i32, align 4

; 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 i32 @_Z16total_insert_numi(i32 noundef) #1

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z5solvev() #1 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %1) #2
  store i32 1, ptr %1, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #2
  %6 = load i32, ptr @max_diff, align 4, !tbaa !5
  store i32 %6, ptr %2, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #2
  %7 = load i32, ptr @max_diff, align 4, !tbaa !5
  store i32 %7, ptr %3, align 4, !tbaa !5
  br label %8

8:                                                ; preds = %29, %0
  %9 = load i32, ptr %1, align 4, !tbaa !5
  %10 = load i32, ptr %2, align 4, !tbaa !5
  %11 = icmp sle i32 %9, %10
  br i1 %11, label %12, label %30

12:                                               ; preds = %8
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #2
  %13 = load i32, ptr %1, align 4, !tbaa !5
  %14 = load i32, ptr %2, align 4, !tbaa !5
  %15 = add nsw i32 %13, %14
  %16 = sdiv i32 %15, 2
  store i32 %16, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  %17 = load i32, ptr %4, align 4, !tbaa !5
  %18 = call noundef i32 @_Z16total_insert_numi(i32 noundef %17)
  store i32 %18, ptr %5, align 4, !tbaa !5
  %19 = load i32, ptr %5, align 4, !tbaa !5
  %20 = load i32, ptr @k, align 4, !tbaa !5
  %21 = icmp sgt i32 %19, %20
  br i1 %21, label %22, label %25

22:                                               ; preds = %12
  %23 = load i32, ptr %4, align 4, !tbaa !5
  %24 = add nsw i32 %23, 1
  store i32 %24, ptr %1, align 4, !tbaa !5
  br label %29

25:                                               ; preds = %12
  %26 = load i32, ptr %4, align 4, !tbaa !5
  store i32 %26, ptr %3, align 4, !tbaa !5
  %27 = load i32, ptr %4, align 4, !tbaa !5
  %28 = sub nsw i32 %27, 1
  store i32 %28, ptr %2, align 4, !tbaa !5
  br label %29

29:                                               ; preds = %25, %22
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #2
  br label %8, !llvm.loop !9

30:                                               ; preds = %8
  %31 = load i32, ptr %3, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %1) #2
  ret i32 %31
}

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 = { 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"}


; 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"

@k = external dso_local local_unnamed_addr global i32, align 4
@max_diff = external dso_local local_unnamed_addr global i32, align 4

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef i32 @_Z16total_insert_numi(i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z5solvev() local_unnamed_addr #0 {
  %1 = load i32, ptr @max_diff, align 4, !tbaa !5
  %.not14 = icmp slt i32 %1, 1
  br i1 %.not14, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %0, %.lr.ph
  %.017 = phi i32 [ %.1, %.lr.ph ], [ 1, %0 ]
  %.01016 = phi i32 [ %.111, %.lr.ph ], [ %1, %0 ]
  %.01215 = phi i32 [ %.113, %.lr.ph ], [ %1, %0 ]
  %2 = add nuw nsw i32 %.017, %.01016
  %3 = lshr i32 %2, 1
  %4 = tail call noundef i32 @_Z16total_insert_numi(i32 noundef %3)
  %5 = load i32, ptr @k, align 4, !tbaa !5
  %6 = icmp sgt i32 %4, %5
  %7 = add nuw nsw i32 %3, 1
  %8 = add nsw i32 %3, -1
  %.113 = select i1 %6, i32 %.01215, i32 %3
  %.111 = select i1 %6, i32 %.01016, i32 %8
  %.1 = select i1 %6, i32 %7, i32 %.017
  %.not = icmp sgt i32 %.1, %.111
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !9

._crit_edge:                                      ; preds = %.lr.ph, %0
  %.012.lcssa = phi i32 [ %1, %0 ], [ %.113, %.lr.ph ]
  ret i32 %.012.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" }

!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,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass,TailCallElimPass