; LLVM IR from MrSupW/C-Source-Code-of-Sorting-Algorithm :: 排序11 快速排序优化(优化递归操作).ll (Z5QSortPiii)

; 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 noundef i32 @_Z9PartitionPiii(ptr noundef, i32 noundef, i32 noundef) #1

; Function Attrs: mustprogress uwtable
define dso_local void @_Z5QSortPiii(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
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #3
  br label %8

8:                                                ; preds = %38, %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 %39

12:                                               ; preds = %8
  %13 = load ptr, ptr %4, align 8, !tbaa !5
  %14 = load i32, ptr %5, align 4, !tbaa !9
  %15 = load i32, ptr %6, align 4, !tbaa !9
  %16 = call noundef i32 @_Z9PartitionPiii(ptr noundef %13, i32 noundef %14, i32 noundef %15)
  store i32 %16, ptr %7, align 4, !tbaa !9
  %17 = load i32, ptr %7, align 4, !tbaa !9
  %18 = load i32, ptr %5, align 4, !tbaa !9
  %19 = sub nsw i32 %17, %18
  %20 = load i32, ptr %6, align 4, !tbaa !9
  %21 = load i32, ptr %7, align 4, !tbaa !9
  %22 = sub nsw i32 %20, %21
  %23 = icmp slt i32 %19, %22
  br i1 %23, label %24, label %31

24:                                               ; preds = %12
  %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 = sub nsw i32 %27, 1
  call void @_Z5QSortPiii(ptr noundef %25, i32 noundef %26, i32 noundef %28)
  %29 = load i32, ptr %7, align 4, !tbaa !9
  %30 = add nsw i32 %29, 1
  store i32 %30, ptr %5, align 4, !tbaa !9
  br label %38

31:                                               ; preds = %12
  %32 = load ptr, ptr %4, align 8, !tbaa !5
  %33 = load i32, ptr %7, align 4, !tbaa !9
  %34 = add nsw i32 %33, 1
  %35 = load i32, ptr %6, align 4, !tbaa !9
  call void @_Z5QSortPiii(ptr noundef %32, i32 noundef %34, i32 noundef %35)
  %36 = load i32, ptr %7, align 4, !tbaa !9
  %37 = sub nsw i32 %36, 1
  store i32 %37, ptr %6, align 4, !tbaa !9
  br label %38

38:                                               ; preds = %31, %24
  br label %8, !llvm.loop !11

39:                                               ; preds = %8
  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}
!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"

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef i32 @_Z9PartitionPiii(ptr noundef, i32 noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local void @_Z5QSortPiii(ptr noundef %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %4 = icmp slt i32 %1, %2
  br i1 %4, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %3, %15
  %.019 = phi i32 [ %.1, %15 ], [ %1, %3 ]
  %.01618 = phi i32 [ %.117, %15 ], [ %2, %3 ]
  %5 = tail call noundef i32 @_Z9PartitionPiii(ptr noundef %0, i32 noundef %.019, i32 noundef %.01618)
  %6 = sub nsw i32 %5, %.019
  %7 = sub nsw i32 %.01618, %5
  %8 = icmp slt i32 %6, %7
  br i1 %8, label %9, label %12

9:                                                ; preds = %.lr.ph
  %10 = add nsw i32 %5, -1
  tail call void @_Z5QSortPiii(ptr noundef %0, i32 noundef %.019, i32 noundef %10)
  %11 = add nsw i32 %5, 1
  br label %15

12:                                               ; preds = %.lr.ph
  %13 = add nsw i32 %5, 1
  tail call void @_Z5QSortPiii(ptr noundef %0, i32 noundef %13, i32 noundef %.01618)
  %14 = add nsw i32 %5, -1
  br label %15

15:                                               ; preds = %12, %9
  %.117 = phi i32 [ %.01618, %9 ], [ %14, %12 ]
  %.1 = phi i32 [ %11, %9 ], [ %.019, %12 ]
  %16 = icmp slt i32 %.1, %.117
  br i1 %16, label %.lr.ph, label %._crit_edge, !llvm.loop !5

._crit_edge:                                      ; preds = %15, %3
  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" }

!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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass