; LLVM IR from ritikbanger/Hacktoberfest2022-DSA :: 06. Sorting/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: 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 void @_Z5mergePiiii(ptr noundef, i32 noundef, i32 noundef, i32 noundef) #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
  %8 = 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
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #3
  %9 = load i32, ptr %5, align 4, !tbaa !9
  %10 = load i32, ptr %6, align 4, !tbaa !9
  %11 = icmp slt i32 %9, %10
  br i1 %11, label %12, label %30

12:                                               ; preds = %3
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #3
  %13 = load i32, ptr %5, align 4, !tbaa !9
  %14 = load i32, ptr %6, align 4, !tbaa !9
  %15 = load i32, ptr %5, align 4, !tbaa !9
  %16 = sub nsw i32 %14, %15
  %17 = sdiv i32 %16, 2
  %18 = add nsw i32 %13, %17
  store i32 %18, ptr %8, align 4, !tbaa !9
  %19 = load ptr, ptr %4, align 8, !tbaa !5
  %20 = load i32, ptr %5, align 4, !tbaa !9
  %21 = load i32, ptr %8, align 4, !tbaa !9
  call void @_Z9mergeSortPiii(ptr noundef %19, i32 noundef %20, i32 noundef %21)
  %22 = load ptr, ptr %4, align 8, !tbaa !5
  %23 = load i32, ptr %8, align 4, !tbaa !9
  %24 = add nsw i32 %23, 1
  %25 = load i32, ptr %6, align 4, !tbaa !9
  call void @_Z9mergeSortPiii(ptr noundef %22, i32 noundef %24, i32 noundef %25)
  %26 = load ptr, ptr %4, align 8, !tbaa !5
  %27 = load i32, ptr %5, align 4, !tbaa !9
  %28 = load i32, ptr %8, align 4, !tbaa !9
  %29 = load i32, ptr %6, align 4, !tbaa !9
  call void @_Z5mergePiiii(ptr noundef %26, i32 noundef %27, i32 noundef %28, i32 noundef %29)
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #3
  br label %30

30:                                               ; preds = %12, %3
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #3
  ret void
}

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 = { 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 @_Z5mergePiiii(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 {
  %4 = icmp slt i32 %1, %2
  br i1 %4, label %5, label %common.ret15

common.ret15:                                     ; preds = %3, %5
  ret void

5:                                                ; preds = %3
  %6 = sub nsw i32 %2, %1
  %7 = sdiv i32 %6, 2
  %8 = add nsw i32 %7, %1
  tail call void @_Z9mergeSortPiii(ptr noundef %0, i32 noundef %1, i32 noundef %8)
  %9 = add nsw i32 %8, 1
  tail call void @_Z9mergeSortPiii(ptr noundef %0, i32 noundef %9, i32 noundef %2)
  tail call void @_Z5mergePiiii(ptr noundef %0, i32 noundef %1, i32 noundef %8, i32 noundef %2)
  br label %common.ret15
}

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,SROAPass,SimplifyCFGPass,TailCallElimPass