; LLVM IR from LeetCode-in-C/LeetCode-in-C :: src/main/c/g0001_0100/s0096_unique_binary_search_trees (Solution)

; 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: nounwind uwtable
define dso_local i32 @numTrees(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca i64, align 8
  %4 = alloca i32, align 4
  store i32 %0, ptr %2, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #2
  store i64 1, ptr %3, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #2
  store i32 0, ptr %4, align 4, !tbaa !5
  br label %5

5:                                                ; preds = %24, %1
  %6 = load i32, ptr %4, align 4, !tbaa !5
  %7 = load i32, ptr %2, align 4, !tbaa !5
  %8 = icmp slt i32 %6, %7
  br i1 %8, label %10, label %9

9:                                                ; preds = %5
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #2
  br label %27

10:                                               ; preds = %5
  %11 = load i32, ptr %2, align 4, !tbaa !5
  %12 = sext i32 %11 to i64
  %13 = mul nsw i64 2, %12
  %14 = load i32, ptr %4, align 4, !tbaa !5
  %15 = sext i32 %14 to i64
  %16 = sub nsw i64 %13, %15
  %17 = load i64, ptr %3, align 8, !tbaa !9
  %18 = mul nsw i64 %17, %16
  store i64 %18, ptr %3, align 8, !tbaa !9
  %19 = load i32, ptr %4, align 4, !tbaa !5
  %20 = add nsw i32 %19, 1
  %21 = sext i32 %20 to i64
  %22 = load i64, ptr %3, align 8, !tbaa !9
  %23 = sdiv i64 %22, %21
  store i64 %23, ptr %3, align 8, !tbaa !9
  br label %24

24:                                               ; preds = %10
  %25 = load i32, ptr %4, align 4, !tbaa !5
  %26 = add nsw i32 %25, 1
  store i32 %26, ptr %4, align 4, !tbaa !5
  br label %5, !llvm.loop !11

27:                                               ; preds = %9
  %28 = load i32, ptr %2, align 4, !tbaa !5
  %29 = add nsw i32 %28, 1
  %30 = sext i32 %29 to i64
  %31 = load i64, ptr %3, align 8, !tbaa !9
  %32 = sdiv i64 %31, %30
  store i64 %32, ptr %3, align 8, !tbaa !9
  %33 = load i64, ptr %3, align 8, !tbaa !9
  %34 = trunc i64 %33 to i32
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #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 = { 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/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"long", !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: nofree norecurse nosync nounwind memory(none) uwtable
define dso_local i32 @numTrees(i32 noundef %0) local_unnamed_addr #0 {
  %2 = icmp sgt i32 %0, 0
  br i1 %2, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %1
  %3 = shl nuw i32 %0, 1
  %4 = zext i32 %3 to i64
  %wide.trip.count = zext nneg i32 %0 to i64
  %xtraiter = and i64 %wide.trip.count, 1
  %5 = icmp eq i32 %0, 1
  br i1 %5, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph.new

.lr.ph.new:                                       ; preds = %.lr.ph
  %unroll_iter = and i64 %wide.trip.count, 2147483646
  br label %13

._crit_edge.loopexit.unr-lcssa:                   ; preds = %13, %.lr.ph
  %.lcssa.ph = phi i64 [ poison, %.lr.ph ], [ %19, %13 ]
  %indvars.iv.unr = phi i64 [ 0, %.lr.ph ], [ %indvars.iv.next.1, %13 ]
  %.01113.unr = phi i64 [ 1, %.lr.ph ], [ %19, %13 ]
  %lcmp.mod.not = icmp eq i64 %xtraiter, 0
  br i1 %lcmp.mod.not, label %._crit_edge, label %._crit_edge.loopexit.epilog-lcssa

._crit_edge.loopexit.epilog-lcssa:                ; preds = %._crit_edge.loopexit.unr-lcssa
  %6 = sub nsw i64 %4, %indvars.iv.unr
  %7 = mul nsw i64 %6, %.01113.unr
  %indvars.iv.next.epil = add nuw nsw i64 %indvars.iv.unr, 1
  %8 = sdiv i64 %7, %indvars.iv.next.epil
  br label %._crit_edge

._crit_edge:                                      ; preds = %._crit_edge.loopexit.epilog-lcssa, %._crit_edge.loopexit.unr-lcssa, %1
  %.011.lcssa = phi i64 [ 1, %1 ], [ %.lcssa.ph, %._crit_edge.loopexit.unr-lcssa ], [ %8, %._crit_edge.loopexit.epilog-lcssa ]
  %9 = add nsw i32 %0, 1
  %10 = sext i32 %9 to i64
  %11 = sdiv i64 %.011.lcssa, %10
  %12 = trunc i64 %11 to i32
  ret i32 %12

13:                                               ; preds = %13, %.lr.ph.new
  %indvars.iv = phi i64 [ 0, %.lr.ph.new ], [ %indvars.iv.next.1, %13 ]
  %.01113 = phi i64 [ 1, %.lr.ph.new ], [ %19, %13 ]
  %niter = phi i64 [ 0, %.lr.ph.new ], [ %niter.next.1, %13 ]
  %14 = sub nsw i64 %4, %indvars.iv
  %15 = mul nsw i64 %14, %.01113
  %indvars.iv.next = or disjoint i64 %indvars.iv, 1
  %16 = sdiv i64 %15, %indvars.iv.next
  %17 = sub nsw i64 %4, %indvars.iv.next
  %18 = mul nsw i64 %17, %16
  %indvars.iv.next.1 = add nuw nsw i64 %indvars.iv, 2
  %19 = sdiv i64 %18, %indvars.iv.next.1
  %niter.next.1 = add i64 %niter, 2
  %niter.ncmp.1 = icmp eq i64 %niter.next.1, %unroll_iter
  br i1 %niter.ncmp.1, label %._crit_edge.loopexit.unr-lcssa, label %13, !llvm.loop !5
}

attributes #0 = { nofree norecurse nosync nounwind memory(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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


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