; LLVM IR from Leet-Us-Code/DSA-A-Z-Practice :: Sid's Levels/Level - 1/LinkedList/reverseLinkedListDataIterative.ll (Z8getAtIndP4Nodei)

; 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.Node = type { i32, ptr }

; Function Attrs: mustprogress nounwind uwtable
declare dso_local noundef i32 @_Z7getSizeP4Node(ptr noundef) #0

; 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

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z8getAtIndP4Nodei(ptr noundef %0, i32 noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca ptr, align 8
  %9 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  %10 = load ptr, ptr %4, align 8, !tbaa !5
  %11 = call noundef i32 @_Z7getSizeP4Node(ptr noundef %10)
  store i32 %11, ptr %6, align 4, !tbaa !9
  %12 = load i32, ptr %6, align 4, !tbaa !9
  %13 = icmp eq i32 %12, 0
  br i1 %13, label %14, label %15

14:                                               ; preds = %2
  store i32 -1, ptr %3, align 4
  store i32 1, ptr %7, align 4
  br label %39

15:                                               ; preds = %2
  %16 = load i32, ptr %5, align 4, !tbaa !9
  %17 = icmp slt i32 %16, 0
  br i1 %17, label %22, label %18

18:                                               ; preds = %15
  %19 = load i32, ptr %5, align 4, !tbaa !9
  %20 = load i32, ptr %6, align 4, !tbaa !9
  %21 = icmp sge i32 %19, %20
  br i1 %21, label %22, label %23

22:                                               ; preds = %18, %15
  store i32 -1, ptr %3, align 4
  store i32 1, ptr %7, align 4
  br label %39

23:                                               ; preds = %18
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #2
  %24 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %24, ptr %8, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %9) #2
  store i32 0, ptr %9, align 4, !tbaa !9
  br label %25

25:                                               ; preds = %29, %23
  %26 = load i32, ptr %9, align 4, !tbaa !9
  %27 = load i32, ptr %5, align 4, !tbaa !9
  %28 = icmp slt i32 %26, %27
  br i1 %28, label %29, label %35

29:                                               ; preds = %25
  %30 = load ptr, ptr %8, align 8, !tbaa !5
  %31 = getelementptr inbounds %struct.Node, ptr %30, i32 0, i32 1
  %32 = load ptr, ptr %31, align 8, !tbaa !11
  store ptr %32, ptr %8, align 8, !tbaa !5
  %33 = load i32, ptr %9, align 4, !tbaa !9
  %34 = add nsw i32 %33, 1
  store i32 %34, ptr %9, align 4, !tbaa !9
  br label %25, !llvm.loop !13

35:                                               ; preds = %25
  %36 = load ptr, ptr %8, align 8, !tbaa !5
  %37 = getelementptr inbounds %struct.Node, ptr %36, i32 0, i32 0
  %38 = load i32, ptr %37, align 8, !tbaa !15
  store i32 %38, ptr %3, align 4
  store i32 1, ptr %7, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %9) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #2
  br label %39

39:                                               ; preds = %35, %22, %14
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  %40 = load i32, ptr %3, align 4
  ret i32 %40
}

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 = !{!"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 = !{!12, !6, i64 8}
!12 = !{!"_ZTS4Node", !10, i64 0, !6, i64 8}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}
!15 = !{!12, !10, i64 0}


; 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 @_Z7getSizeP4Node(ptr noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z8getAtIndP4Nodei(ptr noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = tail call noundef i32 @_Z7getSizeP4Node(ptr noundef %0)
  %4 = icmp eq i32 %3, 0
  br i1 %4, label %27, label %5

5:                                                ; preds = %2
  %6 = icmp sgt i32 %1, -1
  %.not = icmp sgt i32 %3, %1
  %or.cond = and i1 %6, %.not
  br i1 %or.cond, label %.preheader, label %27

.preheader:                                       ; preds = %5
  %.not17 = icmp eq i32 %1, 0
  br i1 %.not17, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %.preheader
  %xtraiter = and i32 %1, 7
  %7 = icmp ult i32 %1, 8
  br i1 %7, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph.preheader.new

.lr.ph.preheader.new:                             ; preds = %.lr.ph.preheader
  %unroll_iter = and i32 %1, 2147483640
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph, %.lr.ph.preheader.new
  %.01115 = phi ptr [ %0, %.lr.ph.preheader.new ], [ %23, %.lr.ph ]
  %niter = phi i32 [ 0, %.lr.ph.preheader.new ], [ %niter.next.7, %.lr.ph ]
  %8 = getelementptr inbounds i8, ptr %.01115, i64 8
  %9 = load ptr, ptr %8, align 8, !tbaa !5
  %10 = getelementptr inbounds i8, ptr %9, i64 8
  %11 = load ptr, ptr %10, align 8, !tbaa !5
  %12 = getelementptr inbounds i8, ptr %11, i64 8
  %13 = load ptr, ptr %12, align 8, !tbaa !5
  %14 = getelementptr inbounds i8, ptr %13, i64 8
  %15 = load ptr, ptr %14, align 8, !tbaa !5
  %16 = getelementptr inbounds i8, ptr %15, i64 8
  %17 = load ptr, ptr %16, align 8, !tbaa !5
  %18 = getelementptr inbounds i8, ptr %17, i64 8
  %19 = load ptr, ptr %18, align 8, !tbaa !5
  %20 = getelementptr inbounds i8, ptr %19, i64 8
  %21 = load ptr, ptr %20, align 8, !tbaa !5
  %22 = getelementptr inbounds i8, ptr %21, i64 8
  %23 = load ptr, ptr %22, align 8, !tbaa !5
  %niter.next.7 = add i32 %niter, 8
  %niter.ncmp.7 = icmp eq i32 %niter.next.7, %unroll_iter
  br i1 %niter.ncmp.7, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph, !llvm.loop !11

._crit_edge.loopexit.unr-lcssa:                   ; preds = %.lr.ph, %.lr.ph.preheader
  %.lcssa.ph = phi ptr [ poison, %.lr.ph.preheader ], [ %23, %.lr.ph ]
  %.01115.unr = phi ptr [ %0, %.lr.ph.preheader ], [ %23, %.lr.ph ]
  %lcmp.mod.not = icmp eq i32 %xtraiter, 0
  br i1 %lcmp.mod.not, label %._crit_edge, label %.lr.ph.epil

.lr.ph.epil:                                      ; preds = %._crit_edge.loopexit.unr-lcssa, %.lr.ph.epil
  %.01115.epil = phi ptr [ %25, %.lr.ph.epil ], [ %.01115.unr, %._crit_edge.loopexit.unr-lcssa ]
  %epil.iter = phi i32 [ %epil.iter.next, %.lr.ph.epil ], [ 0, %._crit_edge.loopexit.unr-lcssa ]
  %24 = getelementptr inbounds i8, ptr %.01115.epil, i64 8
  %25 = load ptr, ptr %24, align 8, !tbaa !5
  %epil.iter.next = add i32 %epil.iter, 1
  %epil.iter.cmp.not = icmp eq i32 %epil.iter.next, %xtraiter
  br i1 %epil.iter.cmp.not, label %._crit_edge, label %.lr.ph.epil, !llvm.loop !13

._crit_edge:                                      ; preds = %._crit_edge.loopexit.unr-lcssa, %.lr.ph.epil, %.preheader
  %.011.lcssa = phi ptr [ %0, %.preheader ], [ %.lcssa.ph, %._crit_edge.loopexit.unr-lcssa ], [ %25, %.lr.ph.epil ]
  %26 = load i32, ptr %.011.lcssa, align 8, !tbaa !15
  br label %27

27:                                               ; preds = %5, %2, %._crit_edge
  %.012 = phi i32 [ %26, %._crit_edge ], [ -1, %2 ], [ -1, %5 ]
  ret i32 %.012
}

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 = !{!6, !10, i64 8}
!6 = !{!"_ZTS4Node", !7, i64 0, !10, i64 8}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.unroll.disable"}
!15 = !{!6, !7, i64 0}


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