; LLVM IR from Lodour/ACM-CheatSheet :: src/7_动态规划/1_子序列/2_最长上升子序列LIS.ll (Z4Findiii)

; 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"

@a = external dso_local global [100100 x i32], align 16
@b = external dso_local global [100100 x i32], align 16
@f = external dso_local global [100100 x i32], align 16

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z4Findiii(i32 noundef %0, i32 noundef %1, i32 noundef %2) #0 {
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store i32 %0, ptr %4, align 4, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !5
  store i32 %2, ptr %6, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  br label %8

8:                                                ; preds = %32, %3
  %9 = load i32, ptr %5, align 4, !tbaa !5
  %10 = load i32, ptr %6, align 4, !tbaa !5
  %11 = icmp sle i32 %9, %10
  br i1 %11, label %12, label %33

12:                                               ; preds = %8
  %13 = load i32, ptr %5, align 4, !tbaa !5
  %14 = load i32, ptr %6, align 4, !tbaa !5
  %15 = add nsw i32 %13, %14
  %16 = ashr i32 %15, 1
  store i32 %16, ptr %7, align 4, !tbaa !5
  %17 = load i32, ptr %4, align 4, !tbaa !5
  %18 = sext i32 %17 to i64
  %19 = getelementptr inbounds [100100 x i32], ptr @a, i64 0, i64 %18
  %20 = load i32, ptr %19, align 4, !tbaa !5
  %21 = load i32, ptr %7, align 4, !tbaa !5
  %22 = sext i32 %21 to i64
  %23 = getelementptr inbounds [100100 x i32], ptr @b, i64 0, i64 %22
  %24 = load i32, ptr %23, align 4, !tbaa !5
  %25 = icmp sgt i32 %20, %24
  br i1 %25, label %26, label %29

26:                                               ; preds = %12
  %27 = load i32, ptr %7, align 4, !tbaa !5
  %28 = add nsw i32 %27, 1
  store i32 %28, ptr %5, align 4, !tbaa !5
  br label %32

29:                                               ; preds = %12
  %30 = load i32, ptr %7, align 4, !tbaa !5
  %31 = sub nsw i32 %30, 1
  store i32 %31, ptr %6, align 4, !tbaa !5
  br label %32

32:                                               ; preds = %29, %26
  br label %8, !llvm.loop !9

33:                                               ; preds = %8
  %34 = load i32, ptr %5, align 4, !tbaa !5
  %35 = load i32, ptr %4, align 4, !tbaa !5
  %36 = sext i32 %35 to i64
  %37 = getelementptr inbounds [100100 x i32], ptr @f, i64 0, i64 %36
  store i32 %34, ptr %37, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  ret i32 %34
}

; 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

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 = { 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"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"

@a = external dso_local local_unnamed_addr global [100100 x i32], align 16
@b = external dso_local local_unnamed_addr global [100100 x i32], align 16
@f = external dso_local local_unnamed_addr global [100100 x i32], align 16

; Function Attrs: mustprogress nofree norecurse nosync nounwind memory(readwrite, argmem: none, inaccessiblemem: none) uwtable
define dso_local noundef i32 @_Z4Findiii(i32 noundef %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %.not12 = icmp sgt i32 %1, %2
  %.pre = sext i32 %0 to i64
  br i1 %.not12, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %3
  %4 = getelementptr inbounds [100100 x i32], ptr @a, i64 0, i64 %.pre
  %5 = load i32, ptr %4, align 4, !tbaa !5
  br label %6

6:                                                ; preds = %.lr.ph, %6
  %.014 = phi i32 [ %1, %.lr.ph ], [ %.1, %6 ]
  %.01013 = phi i32 [ %2, %.lr.ph ], [ %.111, %6 ]
  %7 = add nsw i32 %.014, %.01013
  %8 = ashr i32 %7, 1
  %9 = sext i32 %8 to i64
  %10 = getelementptr inbounds [100100 x i32], ptr @b, i64 0, i64 %9
  %11 = load i32, ptr %10, align 4, !tbaa !5
  %12 = icmp sgt i32 %5, %11
  %13 = add nsw i32 %8, 1
  %14 = add nsw i32 %8, -1
  %.111 = select i1 %12, i32 %.01013, i32 %14
  %.1 = select i1 %12, i32 %13, i32 %.014
  %.not = icmp sgt i32 %.1, %.111
  br i1 %.not, label %._crit_edge, label %6, !llvm.loop !9

._crit_edge:                                      ; preds = %6, %3
  %.0.lcssa = phi i32 [ %1, %3 ], [ %.1, %6 ]
  %15 = getelementptr inbounds [100100 x i32], ptr @f, i64 0, i64 %.pre
  store i32 %.0.lcssa, ptr %15, align 4, !tbaa !5
  ret i32 %.0.lcssa
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind memory(readwrite, argmem: none, inaccessiblemem: none) 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++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LICMPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass