; LLVM IR from smv1999/CompetitiveProgrammingQuestionBank :: Sorting Algorithms/merge_sort.ll (Z9mergeSortPiii)

; 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"

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_Z10mergeArrayPiiii(ptr noundef, i32 noundef, i32 noundef, i32 noundef) #0

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

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

; Function Attrs: mustprogress uwtable
define dso_local void @_Z9mergeSortPiii(ptr noundef %0, i32 noundef %1, i32 noundef %2) #2 {
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  store i32 %2, ptr %6, align 4, !tbaa !9
  %8 = load i32, ptr %5, align 4, !tbaa !9
  %9 = load i32, ptr %6, align 4, !tbaa !9
  %10 = icmp sge i32 %8, %9
  br i1 %10, label %11, label %12

11:                                               ; preds = %3
  br label %29

12:                                               ; preds = %3
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #3
  %13 = load i32, ptr %5, align 4, !tbaa !9
  %14 = load i32, ptr %6, align 4, !tbaa !9
  %15 = add nsw i32 %13, %14
  %16 = sub nsw i32 %15, 1
  %17 = sdiv i32 %16, 2
  store i32 %17, ptr %7, align 4, !tbaa !9
  %18 = load ptr, ptr %4, align 8, !tbaa !5
  %19 = load i32, ptr %5, align 4, !tbaa !9
  %20 = load i32, ptr %7, align 4, !tbaa !9
  call void @_Z9mergeSortPiii(ptr noundef %18, i32 noundef %19, i32 noundef %20)
  %21 = load ptr, ptr %4, align 8, !tbaa !5
  %22 = load i32, ptr %7, align 4, !tbaa !9
  %23 = add nsw i32 %22, 1
  %24 = load i32, ptr %6, align 4, !tbaa !9
  call void @_Z9mergeSortPiii(ptr noundef %21, i32 noundef %23, i32 noundef %24)
  %25 = load ptr, ptr %4, align 8, !tbaa !5
  %26 = load i32, ptr %5, align 4, !tbaa !9
  %27 = load i32, ptr %7, align 4, !tbaa !9
  %28 = load i32, ptr %6, align 4, !tbaa !9
  call void @_Z10mergeArrayPiiii(ptr noundef %25, i32 noundef %26, i32 noundef %27, i32 noundef %28)
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #3
  br label %29

29:                                               ; preds = %12, %11
  ret void
}

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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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" }
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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !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"

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_Z10mergeArrayPiiii(ptr noundef, i32 noundef, i32 noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local void @_Z9mergeSortPiii(ptr noundef %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %.not = icmp slt i32 %1, %2
  br i1 %.not, label %4, label %common.ret14

common.ret14:                                     ; preds = %3, %4
  ret void

4:                                                ; preds = %3
  %5 = add i32 %1, -1
  %6 = add i32 %5, %2
  %7 = sdiv i32 %6, 2
  tail call void @_Z9mergeSortPiii(ptr noundef %0, i32 noundef %1, i32 noundef %7)
  %8 = add nsw i32 %7, 1
  tail call void @_Z9mergeSortPiii(ptr noundef %0, i32 noundef %8, i32 noundef %2)
  tail call void @_Z10mergeArrayPiiii(ptr noundef %0, i32 noundef %1, i32 noundef %7, i32 noundef %2)
  br label %common.ret14
}

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)"}


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