; 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
define dso_local i32 @findBottom(ptr noundef %0, i32 noundef %1) #1 {
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca ptr, align 8
  %7 = 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 8, ptr %6) #2
  %8 = load ptr, ptr %4, align 8, !tbaa !5
  %9 = getelementptr inbounds %struct.LinkedList, ptr %8, i32 0, i32 1
  %10 = load ptr, ptr %9, align 8, !tbaa !11
  %11 = getelementptr inbounds %struct.Node, ptr %10, i32 0, i32 0
  %12 = load ptr, ptr %11, align 8, !tbaa !13
  store ptr %12, ptr %6, align 8, !tbaa !5
  br label %13

13:                                               ; preds = %27, %2
  %14 = load ptr, ptr %6, align 8, !tbaa !5
  %15 = load ptr, ptr %4, align 8, !tbaa !5
  %16 = getelementptr inbounds %struct.LinkedList, ptr %15, i32 0, i32 0
  %17 = load ptr, ptr %16, align 8, !tbaa !15
  %18 = icmp ne ptr %14, %17
  br i1 %18, label %19, label %31

19:                                               ; preds = %13
  %20 = load ptr, ptr %6, align 8, !tbaa !5
  %21 = getelementptr inbounds %struct.Node, ptr %20, i32 0, i32 2
  %22 = load i32, ptr %21, align 8, !tbaa !16
  %23 = load i32, ptr %5, align 4, !tbaa !9
  %24 = icmp eq i32 %22, %23
  br i1 %24, label %25, label %27

25:                                               ; preds = %19
  %26 = load i32, ptr %5, align 4, !tbaa !9
  store i32 %26, ptr %3, align 4
  store i32 1, ptr %7, align 4
  br label %32

27:                                               ; preds = %19
  %28 = load ptr, ptr %6, align 8, !tbaa !5
  %29 = getelementptr inbounds %struct.Node, ptr %28, i32 0, i32 0
  %30 = load ptr, ptr %29, align 8, !tbaa !13
  store ptr %30, ptr %6, align 8, !tbaa !5
  br label %13, !llvm.loop !17

31:                                               ; preds = %13
  store i32 -1, ptr %3, align 4
  store i32 1, ptr %7, align 4
  br label %32

32:                                               ; preds = %31, %25
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #2
  %33 = load i32, ptr %3, align 4
  ret i32 %33
}

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 8}
!12 = !{!"LinkedList", !6, i64 0, !6, i64 8}
!13 = !{!14, !6, i64 0}
!14 = !{!"Node", !6, i64 0, !6, i64 8, !10, i64 16}
!15 = !{!12, !6, i64 0}
!16 = !{!14, !10, i64 16}
!17 = distinct !{!17, !18}
!18 = !{!"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(read, inaccessiblemem: none) uwtable
define dso_local noundef i32 @findBottom(ptr nocapture noundef readonly %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = getelementptr inbounds i8, ptr %0, i64 8
  %4 = load ptr, ptr %3, align 8, !tbaa !5
  %5 = load ptr, ptr %0, align 8, !tbaa !10
  br label %6

6:                                                ; preds = %7, %2
  %.0.in = phi ptr [ %4, %2 ], [ %.0, %7 ]
  %.0 = load ptr, ptr %.0.in, align 8, !tbaa !11
  %.not = icmp eq ptr %.0, %5
  br i1 %.not, label %11, label %7

7:                                                ; preds = %6
  %8 = getelementptr inbounds i8, ptr %.0, i64 16
  %9 = load i32, ptr %8, align 8, !tbaa !14
  %10 = icmp eq i32 %9, %1
  br i1 %10, label %11, label %6, !llvm.loop !15

11:                                               ; preds = %6, %7
  %.07 = phi i32 [ %1, %7 ], [ -1, %6 ]
  ret i32 %.07
}

attributes #0 = { nofree norecurse nosync nounwind memory(read, 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, !7, i64 8}
!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 = !{!6, !7, i64 0}
!11 = !{!12, !7, i64 0}
!12 = !{!"Node", !7, i64 0, !7, i64 8, !13, i64 16}
!13 = !{!"int", !8, i64 0}
!14 = !{!12, !13, i64 16}
!15 = distinct !{!15, !16}
!16 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,LICMPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass