; LLVM IR from xxks-kkk/algo :: stack/generic (stack)

; 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"

%struct.StackRecord = type { i32, i32, ptr }

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nounwind allocsize(0)
declare noalias ptr @malloc(i64 noundef) #1

; Function Attrs: nounwind allocsize(0,1)
declare noalias ptr @calloc(i64 noundef, i64 noundef) #2

; 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
define dso_local ptr @initializeStack(ptr noundef %0, i32 noundef %1) #3 {
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #4
  %7 = call noalias ptr @malloc(i64 noundef 16) #5
  store ptr %7, ptr %5, align 8, !tbaa !5
  %8 = load i32, ptr %4, align 4, !tbaa !9
  %9 = load ptr, ptr %5, align 8, !tbaa !5
  %10 = getelementptr inbounds %struct.StackRecord, ptr %9, i32 0, i32 0
  store i32 %8, ptr %10, align 8, !tbaa !11
  %11 = load i32, ptr %4, align 4, !tbaa !9
  %12 = sext i32 %11 to i64
  %13 = call noalias ptr @calloc(i64 noundef %12, i64 noundef 4) #6
  %14 = load ptr, ptr %5, align 8, !tbaa !5
  %15 = getelementptr inbounds %struct.StackRecord, ptr %14, i32 0, i32 2
  store ptr %13, ptr %15, align 8, !tbaa !13
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #4
  store i32 0, ptr %6, align 4, !tbaa !9
  br label %16

16:                                               ; preds = %32, %2
  %17 = load i32, ptr %6, align 4, !tbaa !9
  %18 = load i32, ptr %4, align 4, !tbaa !9
  %19 = icmp slt i32 %17, %18
  br i1 %19, label %20, label %35

20:                                               ; preds = %16
  %21 = load ptr, ptr %3, align 8, !tbaa !5
  %22 = load i32, ptr %6, align 4, !tbaa !9
  %23 = sext i32 %22 to i64
  %24 = getelementptr inbounds i32, ptr %21, i64 %23
  %25 = load i32, ptr %24, align 4, !tbaa !9
  %26 = load ptr, ptr %5, align 8, !tbaa !5
  %27 = getelementptr inbounds %struct.StackRecord, ptr %26, i32 0, i32 2
  %28 = load ptr, ptr %27, align 8, !tbaa !13
  %29 = load i32, ptr %6, align 4, !tbaa !9
  %30 = sext i32 %29 to i64
  %31 = getelementptr inbounds i32, ptr %28, i64 %30
  store i32 %25, ptr %31, align 4, !tbaa !9
  br label %32

32:                                               ; preds = %20
  %33 = load i32, ptr %6, align 4, !tbaa !9
  %34 = add nsw i32 %33, 1
  store i32 %34, ptr %6, align 4, !tbaa !9
  br label %16, !llvm.loop !14

35:                                               ; preds = %16
  %36 = load ptr, ptr %5, align 8, !tbaa !5
  %37 = getelementptr inbounds %struct.StackRecord, ptr %36, i32 0, i32 0
  %38 = load i32, ptr %37, align 8, !tbaa !11
  %39 = sub nsw i32 %38, 1
  %40 = load ptr, ptr %5, align 8, !tbaa !5
  %41 = getelementptr inbounds %struct.StackRecord, ptr %40, i32 0, i32 1
  store i32 %39, ptr %41, align 4, !tbaa !16
  %42 = load ptr, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #4
  ret ptr %42
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { nounwind allocsize(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 allocsize(0,1) "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 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 }
attributes #5 = { nounwind allocsize(0) }
attributes #6 = { nounwind allocsize(0,1) }

!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 = !{!12, !10, i64 0}
!12 = !{!"StackRecord", !10, i64 0, !10, i64 4, !6, i64 8}
!13 = !{!12, !6, i64 8}
!14 = distinct !{!14, !15}
!15 = !{!"llvm.loop.mustprogress"}
!16 = !{!12, !10, i64 4}


; 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 nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite)
declare noalias noundef ptr @malloc(i64 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nofree nounwind willreturn allockind("alloc,zeroed") allocsize(0,1) memory(inaccessiblemem: readwrite)
declare noalias noundef ptr @calloc(i64 noundef, i64 noundef) local_unnamed_addr #1

; Function Attrs: mustprogress nofree nounwind willreturn uwtable
define dso_local noalias noundef ptr @initializeStack(ptr nocapture noundef readonly %0, i32 noundef %1) local_unnamed_addr #2 {
  %3 = tail call noalias dereferenceable_or_null(16) ptr @malloc(i64 noundef 16) #4
  store i32 %1, ptr %3, align 8, !tbaa !5
  %4 = sext i32 %1 to i64
  %5 = tail call noalias ptr @calloc(i64 noundef %4, i64 noundef 4) #5
  %6 = getelementptr inbounds i8, ptr %3, i64 8
  store ptr %5, ptr %6, align 8, !tbaa !11
  %7 = icmp sgt i32 %1, 0
  br i1 %7, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %2
  %8 = zext nneg i32 %1 to i64
  %9 = shl nuw nsw i64 %8, 2
  tail call void @llvm.memcpy.p0.p0.i64(ptr align 4 %5, ptr align 4 %0, i64 %9, i1 false), !tbaa !12
  br label %._crit_edge

._crit_edge:                                      ; preds = %.lr.ph.preheader, %2
  %10 = add nsw i32 %1, -1
  %11 = getelementptr inbounds i8, ptr %3, i64 4
  store i32 %10, ptr %11, align 4, !tbaa !13
  ret ptr %3
}

; Function Attrs: nocallback nofree nounwind willreturn memory(argmem: readwrite)
declare void @llvm.memcpy.p0.p0.i64(ptr noalias nocapture writeonly, ptr noalias nocapture readonly, i64, i1 immarg) #3

attributes #0 = { mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite) "alloc-family"="malloc" "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 nofree nounwind willreturn allockind("alloc,zeroed") allocsize(0,1) memory(inaccessiblemem: readwrite) "alloc-family"="malloc" "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 nofree nounwind willreturn 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 = { nocallback nofree nounwind willreturn memory(argmem: readwrite) }
attributes #4 = { nounwind allocsize(0) }
attributes #5 = { nounwind allocsize(0,1) }

!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, !7, i64 0}
!6 = !{!"StackRecord", !7, i64 0, !7, i64 4, !10, i64 8}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = !{!6, !10, i64 8}
!12 = !{!7, !7, i64 0}
!13 = !{!6, !7, i64 4}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,LoopIdiomRecognizePass,LoopRotatePass,LoopSimplifyPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass