; LLVM IR from bartobri/data-structures-c :: arrays/recursive-mergesort-wih-cutoff-to-insertion (sort)

; 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"

@aux = external hidden global [100 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: nounwind uwtable
declare dso_local void @mergesortABr(ptr noundef, ptr noundef, i32 noundef, i32 noundef) #1

; Function Attrs: nounwind uwtable
define dso_local void @mergesortAB(ptr noundef %0, i32 noundef %1, i32 noundef %2) #1 {
  %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
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  %8 = load i32, ptr %5, align 4, !tbaa !9
  store i32 %8, ptr %7, align 4, !tbaa !9
  br label %9

9:                                                ; preds = %22, %3
  %10 = load i32, ptr %7, align 4, !tbaa !9
  %11 = load i32, ptr %6, align 4, !tbaa !9
  %12 = icmp sle i32 %10, %11
  br i1 %12, label %13, label %25

13:                                               ; preds = %9
  %14 = load ptr, ptr %4, align 8, !tbaa !5
  %15 = load i32, ptr %7, align 4, !tbaa !9
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds i32, ptr %14, i64 %16
  %18 = load i32, ptr %17, align 4, !tbaa !9
  %19 = load i32, ptr %7, align 4, !tbaa !9
  %20 = sext i32 %19 to i64
  %21 = getelementptr inbounds [100 x i32], ptr @aux, i64 0, i64 %20
  store i32 %18, ptr %21, align 4, !tbaa !9
  br label %22

22:                                               ; preds = %13
  %23 = load i32, ptr %7, align 4, !tbaa !9
  %24 = add nsw i32 %23, 1
  store i32 %24, ptr %7, align 4, !tbaa !9
  br label %9, !llvm.loop !11

25:                                               ; preds = %9
  %26 = load ptr, ptr %4, align 8, !tbaa !5
  %27 = load i32, ptr %5, align 4, !tbaa !9
  %28 = load i32, ptr %6, align 4, !tbaa !9
  call void @mergesortABr(ptr noundef %26, ptr noundef @aux, i32 noundef %27, i32 noundef %28)
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  ret void
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"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"

@aux = external hidden global [100 x i32], align 16

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

; Function Attrs: nounwind uwtable
define dso_local void @mergesortAB(ptr noundef %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %.not10 = icmp sgt i32 %1, %2
  br i1 %.not10, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %3
  %4 = ptrtoint ptr %0 to i64
  %5 = sext i32 %1 to i64
  %6 = add i32 %2, 1
  %7 = sub i32 %2, %1
  %8 = zext i32 %7 to i64
  %9 = add nuw nsw i64 %8, 1
  %min.iters.check = icmp ult i32 %7, 7
  %10 = sub i64 ptrtoint (ptr @aux to i64), %4
  %diff.check = icmp ult i64 %10, 32
  %or.cond = or i1 %min.iters.check, %diff.check
  br i1 %or.cond, label %.lr.ph.preheader15, label %vector.ph

vector.ph:                                        ; preds = %.lr.ph.preheader
  %n.vec = and i64 %9, 8589934584
  %ind.end = add nsw i64 %n.vec, %5
  br label %vector.body

vector.body:                                      ; preds = %vector.body, %vector.ph
  %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
  %offset.idx = add i64 %index, %5
  %11 = getelementptr inbounds i32, ptr %0, i64 %offset.idx
  %12 = getelementptr inbounds i8, ptr %11, i64 16
  %wide.load = load <4 x i32>, ptr %11, align 4, !tbaa !5
  %wide.load14 = load <4 x i32>, ptr %12, align 4, !tbaa !5
  %13 = getelementptr inbounds [100 x i32], ptr @aux, i64 0, i64 %offset.idx
  %14 = getelementptr inbounds i8, ptr %13, i64 16
  store <4 x i32> %wide.load, ptr %13, align 4, !tbaa !5
  store <4 x i32> %wide.load14, ptr %14, align 4, !tbaa !5
  %index.next = add nuw i64 %index, 8
  %15 = icmp eq i64 %index.next, %n.vec
  br i1 %15, label %middle.block, label %vector.body, !llvm.loop !9

middle.block:                                     ; preds = %vector.body
  %cmp.n = icmp eq i64 %9, %n.vec
  br i1 %cmp.n, label %._crit_edge, label %.lr.ph.preheader15

.lr.ph.preheader15:                               ; preds = %middle.block, %.lr.ph.preheader
  %indvars.iv.ph = phi i64 [ %5, %.lr.ph.preheader ], [ %ind.end, %middle.block ]
  %16 = add i32 %2, 1
  %17 = trunc i64 %indvars.iv.ph to i32
  %18 = sub i32 %16, %17
  %19 = sub i32 %2, %17
  %xtraiter = and i32 %18, 3
  %lcmp.mod.not = icmp eq i32 %xtraiter, 0
  br i1 %lcmp.mod.not, label %.lr.ph.prol.loopexit, label %.lr.ph.prol

.lr.ph.prol:                                      ; preds = %.lr.ph.preheader15, %.lr.ph.prol
  %indvars.iv.prol = phi i64 [ %indvars.iv.next.prol, %.lr.ph.prol ], [ %indvars.iv.ph, %.lr.ph.preheader15 ]
  %prol.iter = phi i32 [ %prol.iter.next, %.lr.ph.prol ], [ 0, %.lr.ph.preheader15 ]
  %20 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv.prol
  %21 = load i32, ptr %20, align 4, !tbaa !5
  %22 = getelementptr inbounds [100 x i32], ptr @aux, i64 0, i64 %indvars.iv.prol
  store i32 %21, ptr %22, align 4, !tbaa !5
  %indvars.iv.next.prol = add nsw i64 %indvars.iv.prol, 1
  %prol.iter.next = add i32 %prol.iter, 1
  %prol.iter.cmp.not = icmp eq i32 %prol.iter.next, %xtraiter
  br i1 %prol.iter.cmp.not, label %.lr.ph.prol.loopexit, label %.lr.ph.prol, !llvm.loop !13

.lr.ph.prol.loopexit:                             ; preds = %.lr.ph.prol, %.lr.ph.preheader15
  %indvars.iv.unr = phi i64 [ %indvars.iv.ph, %.lr.ph.preheader15 ], [ %indvars.iv.next.prol, %.lr.ph.prol ]
  %23 = icmp ult i32 %19, 3
  br i1 %23, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.prol.loopexit, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next.3, %.lr.ph ], [ %indvars.iv.unr, %.lr.ph.prol.loopexit ]
  %24 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv
  %25 = load i32, ptr %24, align 4, !tbaa !5
  %26 = getelementptr inbounds [100 x i32], ptr @aux, i64 0, i64 %indvars.iv
  store i32 %25, ptr %26, align 4, !tbaa !5
  %indvars.iv.next = add nsw i64 %indvars.iv, 1
  %27 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv.next
  %28 = load i32, ptr %27, align 4, !tbaa !5
  %29 = getelementptr inbounds [100 x i32], ptr @aux, i64 0, i64 %indvars.iv.next
  store i32 %28, ptr %29, align 4, !tbaa !5
  %indvars.iv.next.1 = add nsw i64 %indvars.iv, 2
  %30 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv.next.1
  %31 = load i32, ptr %30, align 4, !tbaa !5
  %32 = getelementptr inbounds [100 x i32], ptr @aux, i64 0, i64 %indvars.iv.next.1
  store i32 %31, ptr %32, align 4, !tbaa !5
  %indvars.iv.next.2 = add nsw i64 %indvars.iv, 3
  %33 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv.next.2
  %34 = load i32, ptr %33, align 4, !tbaa !5
  %35 = getelementptr inbounds [100 x i32], ptr @aux, i64 0, i64 %indvars.iv.next.2
  store i32 %34, ptr %35, align 4, !tbaa !5
  %indvars.iv.next.3 = add nsw i64 %indvars.iv, 4
  %lftr.wideiv.3 = trunc i64 %indvars.iv.next.3 to i32
  %exitcond.not.3 = icmp eq i32 %6, %lftr.wideiv.3
  br i1 %exitcond.not.3, label %._crit_edge, label %.lr.ph, !llvm.loop !15

._crit_edge:                                      ; preds = %.lr.ph.prol.loopexit, %.lr.ph, %middle.block, %3
  tail call void @mergesortABr(ptr noundef %0, ptr noundef nonnull @aux, i32 noundef %1, i32 noundef %2)
  ret void
}

attributes #0 = { 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/C++ TBAA"}
!9 = distinct !{!9, !10, !11, !12}
!10 = !{!"llvm.loop.mustprogress"}
!11 = !{!"llvm.loop.isvectorized", i32 1}
!12 = !{!"llvm.loop.unroll.runtime.disable"}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.unroll.disable"}
!15 = distinct !{!15, !10, !11}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopLoadEliminationPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,LoopVectorizePass,SROAPass,SimplifyCFGPass,TailCallElimPass