; LLVM IR from sbshah97/DS-Algo-Handbook :: Algorithms/Dynamic_Programming/LIS/lis.ll (Z13biggerElementii)

; 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"

@arr = external dso_local global [20 x i32], align 16

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z13biggerElementii(i32 noundef %0, i32 noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  store i32 1, ptr %5, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  %7 = load i32, ptr %3, align 4, !tbaa !5
  store i32 %7, ptr %6, align 4, !tbaa !5
  br label %8

8:                                                ; preds = %28, %2
  %9 = load i32, ptr %6, align 4, !tbaa !5
  %10 = load i32, ptr %4, align 4, !tbaa !5
  %11 = icmp slt i32 %9, %10
  br i1 %11, label %13, label %12

12:                                               ; preds = %8
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  br label %31

13:                                               ; preds = %8
  %14 = load i32, ptr %6, align 4, !tbaa !5
  %15 = add nsw i32 %14, 1
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds [20 x i32], ptr @arr, i64 0, i64 %16
  %18 = load i32, ptr %17, align 4, !tbaa !5
  %19 = load i32, ptr %6, align 4, !tbaa !5
  %20 = sext i32 %19 to i64
  %21 = getelementptr inbounds [20 x i32], ptr @arr, i64 0, i64 %20
  %22 = load i32, ptr %21, align 4, !tbaa !5
  %23 = icmp sgt i32 %18, %22
  br i1 %23, label %24, label %27

24:                                               ; preds = %13
  %25 = load i32, ptr %5, align 4, !tbaa !5
  %26 = add nsw i32 %25, 1
  store i32 %26, ptr %5, align 4, !tbaa !5
  br label %27

27:                                               ; preds = %24, %13
  br label %28

28:                                               ; preds = %27
  %29 = load i32, ptr %6, align 4, !tbaa !5
  %30 = add nsw i32 %29, 1
  store i32 %30, ptr %6, align 4, !tbaa !5
  br label %8, !llvm.loop !9

31:                                               ; preds = %12
  %32 = load i32, ptr %5, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  ret i32 %32
}

; 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"

@arr = external dso_local local_unnamed_addr global [20 x i32], align 16

; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(read, argmem: none, inaccessiblemem: none) uwtable
define dso_local noundef i32 @_Z13biggerElementii(i32 noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = icmp slt i32 %0, %1
  br i1 %3, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %2
  %4 = sext i32 %0 to i64
  %wide.trip.count = sext i32 %1 to i64
  %.phi.trans.insert = getelementptr inbounds [20 x i32], ptr @arr, i64 0, i64 %4
  %.pre = load i32, ptr %.phi.trans.insert, align 4, !tbaa !5
  %5 = sub nsw i64 %wide.trip.count, %4
  %min.iters.check = icmp ult i64 %5, 8
  br i1 %min.iters.check, label %.lr.ph.preheader14, label %vector.ph

.lr.ph.preheader14:                               ; preds = %middle.block, %.lr.ph.preheader
  %.ph = phi i32 [ %.pre, %.lr.ph.preheader ], [ %vector.recur.extract, %middle.block ]
  %indvars.iv.ph = phi i64 [ %4, %.lr.ph.preheader ], [ %ind.end, %middle.block ]
  %.089.ph = phi i32 [ 1, %.lr.ph.preheader ], [ %18, %middle.block ]
  br label %.lr.ph

vector.ph:                                        ; preds = %.lr.ph.preheader
  %n.vec = and i64 %5, -8
  %ind.end = add nsw i64 %n.vec, %4
  %vector.recur.init = insertelement <4 x i32> poison, i32 %.pre, i64 3
  br label %vector.body

vector.body:                                      ; preds = %vector.body, %vector.ph
  %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
  %vector.recur = phi <4 x i32> [ %vector.recur.init, %vector.ph ], [ %wide.load13, %vector.body ]
  %vec.phi = phi <4 x i32> [ <i32 1, i32 0, i32 0, i32 0>, %vector.ph ], [ %15, %vector.body ]
  %vec.phi12 = phi <4 x i32> [ zeroinitializer, %vector.ph ], [ %16, %vector.body ]
  %offset.idx = add i64 %index, %4
  %6 = add nsw i64 %offset.idx, 1
  %7 = getelementptr inbounds [20 x i32], ptr @arr, i64 0, i64 %6
  %8 = getelementptr inbounds i8, ptr %7, i64 16
  %wide.load = load <4 x i32>, ptr %7, align 4, !tbaa !5
  %wide.load13 = load <4 x i32>, ptr %8, align 4, !tbaa !5
  %9 = shufflevector <4 x i32> %vector.recur, <4 x i32> %wide.load, <4 x i32> <i32 3, i32 4, i32 5, i32 6>
  %10 = shufflevector <4 x i32> %wide.load, <4 x i32> %wide.load13, <4 x i32> <i32 3, i32 4, i32 5, i32 6>
  %11 = icmp sgt <4 x i32> %wide.load, %9
  %12 = icmp sgt <4 x i32> %wide.load13, %10
  %13 = zext <4 x i1> %11 to <4 x i32>
  %14 = zext <4 x i1> %12 to <4 x i32>
  %15 = add <4 x i32> %vec.phi, %13
  %16 = add <4 x i32> %vec.phi12, %14
  %index.next = add nuw i64 %index, 8
  %17 = icmp eq i64 %index.next, %n.vec
  br i1 %17, label %middle.block, label %vector.body, !llvm.loop !9

middle.block:                                     ; preds = %vector.body
  %bin.rdx = add <4 x i32> %16, %15
  %18 = tail call i32 @llvm.vector.reduce.add.v4i32(<4 x i32> %bin.rdx)
  %vector.recur.extract = extractelement <4 x i32> %wide.load13, i64 3
  %cmp.n = icmp eq i64 %5, %n.vec
  br i1 %cmp.n, label %._crit_edge, label %.lr.ph.preheader14

._crit_edge:                                      ; preds = %.lr.ph, %middle.block, %2
  %.08.lcssa = phi i32 [ 1, %2 ], [ %18, %middle.block ], [ %spec.select, %.lr.ph ]
  ret i32 %.08.lcssa

.lr.ph:                                           ; preds = %.lr.ph.preheader14, %.lr.ph
  %19 = phi i32 [ %21, %.lr.ph ], [ %.ph, %.lr.ph.preheader14 ]
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ %indvars.iv.ph, %.lr.ph.preheader14 ]
  %.089 = phi i32 [ %spec.select, %.lr.ph ], [ %.089.ph, %.lr.ph.preheader14 ]
  %indvars.iv.next = add nsw i64 %indvars.iv, 1
  %20 = getelementptr inbounds [20 x i32], ptr @arr, i64 0, i64 %indvars.iv.next
  %21 = load i32, ptr %20, align 4, !tbaa !5
  %22 = icmp sgt i32 %21, %19
  %23 = zext i1 %22 to i32
  %spec.select = add nuw nsw i32 %.089, %23
  %exitcond.not = icmp eq i64 %indvars.iv.next, %wide.trip.count
  br i1 %exitcond.not, label %._crit_edge, label %.lr.ph, !llvm.loop !13
}

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.vector.reduce.add.v4i32(<4 x i32>) #1

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(read, 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" }
attributes #1 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }

!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, !11, !12}
!10 = !{!"llvm.loop.mustprogress"}
!11 = !{!"llvm.loop.isvectorized", i32 1}
!12 = !{!"llvm.loop.unroll.runtime.disable"}
!13 = distinct !{!13, !10, !12, !11}


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