; LLVM IR from JessonYue/LeetCodeLearning :: Array/wuchao/linkedlist/8-1 双向链表 (LinkedList)

; 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.LinkedList = type { ptr, ptr }
%struct.Node = type { ptr, ptr, i32 }

; 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: nounwind uwtable
declare dso_local void @recycleNode(ptr noundef) #1

; Function Attrs: nounwind uwtable
define dso_local i32 @removeFromHead(ptr noundef %0) #1 {
  %2 = alloca ptr, align 8
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #2
  store i32 -1, ptr %3, align 4, !tbaa !9
  %5 = load ptr, ptr %2, align 8, !tbaa !5
  %6 = getelementptr inbounds %struct.LinkedList, ptr %5, i32 0, i32 0
  %7 = load ptr, ptr %6, align 8, !tbaa !11
  %8 = getelementptr inbounds %struct.Node, ptr %7, i32 0, i32 1
  %9 = load ptr, ptr %8, align 8, !tbaa !13
  %10 = load ptr, ptr %2, align 8, !tbaa !5
  %11 = getelementptr inbounds %struct.LinkedList, ptr %10, i32 0, i32 1
  %12 = load ptr, ptr %11, align 8, !tbaa !15
  %13 = icmp ne ptr %9, %12
  br i1 %13, label %14, label %38

14:                                               ; preds = %1
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #2
  %15 = load ptr, ptr %2, align 8, !tbaa !5
  %16 = getelementptr inbounds %struct.LinkedList, ptr %15, i32 0, i32 0
  %17 = load ptr, ptr %16, align 8, !tbaa !11
  %18 = getelementptr inbounds %struct.Node, ptr %17, i32 0, i32 1
  %19 = load ptr, ptr %18, align 8, !tbaa !13
  store ptr %19, ptr %4, align 8, !tbaa !5
  %20 = load ptr, ptr %4, align 8, !tbaa !5
  %21 = getelementptr inbounds %struct.Node, ptr %20, i32 0, i32 1
  %22 = load ptr, ptr %21, align 8, !tbaa !13
  %23 = load ptr, ptr %2, align 8, !tbaa !5
  %24 = getelementptr inbounds %struct.LinkedList, ptr %23, i32 0, i32 0
  %25 = load ptr, ptr %24, align 8, !tbaa !11
  %26 = getelementptr inbounds %struct.Node, ptr %25, i32 0, i32 1
  store ptr %22, ptr %26, align 8, !tbaa !13
  %27 = load ptr, ptr %2, align 8, !tbaa !5
  %28 = getelementptr inbounds %struct.LinkedList, ptr %27, i32 0, i32 0
  %29 = load ptr, ptr %28, align 8, !tbaa !11
  %30 = load ptr, ptr %4, align 8, !tbaa !5
  %31 = getelementptr inbounds %struct.Node, ptr %30, i32 0, i32 1
  %32 = load ptr, ptr %31, align 8, !tbaa !13
  %33 = getelementptr inbounds %struct.Node, ptr %32, i32 0, i32 0
  store ptr %29, ptr %33, align 8, !tbaa !16
  %34 = load ptr, ptr %4, align 8, !tbaa !5
  %35 = getelementptr inbounds %struct.Node, ptr %34, i32 0, i32 2
  %36 = load i32, ptr %35, align 8, !tbaa !17
  store i32 %36, ptr %3, align 4, !tbaa !9
  %37 = load ptr, ptr %4, align 8, !tbaa !5
  call void @recycleNode(ptr noundef %37)
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #2
  br label %38

38:                                               ; preds = %14, %1
  %39 = load i32, ptr %3, align 4, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #2
  ret i32 %39
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 = { 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/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{!12, !6, i64 0}
!12 = !{!"LinkedList", !6, i64 0, !6, i64 8}
!13 = !{!14, !6, i64 8}
!14 = !{!"Node", !6, i64 0, !6, i64 8, !10, i64 16}
!15 = !{!12, !6, i64 8}
!16 = !{!14, !6, i64 0}
!17 = !{!14, !10, i64 16}


; 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: nounwind uwtable
declare dso_local void @recycleNode(ptr noundef) local_unnamed_addr #0

; Function Attrs: nounwind uwtable
define dso_local i32 @removeFromHead(ptr nocapture noundef readonly %0) local_unnamed_addr #0 {
  %2 = load ptr, ptr %0, align 8, !tbaa !5
  %3 = getelementptr inbounds i8, ptr %2, i64 8
  %4 = load ptr, ptr %3, align 8, !tbaa !10
  %5 = getelementptr inbounds i8, ptr %0, i64 8
  %6 = load ptr, ptr %5, align 8, !tbaa !13
  %.not = icmp eq ptr %4, %6
  br i1 %.not, label %12, label %7

7:                                                ; preds = %1
  %8 = getelementptr inbounds i8, ptr %4, i64 8
  %9 = load ptr, ptr %8, align 8, !tbaa !10
  store ptr %9, ptr %3, align 8, !tbaa !10
  store ptr %2, ptr %9, align 8, !tbaa !14
  %10 = getelementptr inbounds i8, ptr %4, i64 16
  %11 = load i32, ptr %10, align 8, !tbaa !15
  tail call void @recycleNode(ptr noundef %4)
  br label %12

12:                                               ; preds = %7, %1
  %.0 = phi i32 [ %11, %7 ], [ -1, %1 ]
  ret i32 %.0
}

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" }

!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, !7, i64 0}
!6 = !{!"LinkedList", !7, i64 0, !7, i64 8}
!7 = !{!"any pointer", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!11, !7, i64 8}
!11 = !{!"Node", !7, i64 0, !7, i64 8, !12, i64 16}
!12 = !{!"int", !8, i64 0}
!13 = !{!6, !7, i64 8}
!14 = !{!11, !7, i64 0}
!15 = !{!11, !12, i64 16}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,PostOrderFunctionAttrsPass,SROAPass,TailCallElimPass