; LLVM IR from div-bargali/Data-Structures-and-Algorithms :: C/Data-Structures/LinkedList (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.node = type { i32, i32, ptr }

@head = external dso_local global ptr, align 8

; 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 ptr @find(i32 noundef %0) #1 {
  %2 = alloca ptr, align 8
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #2
  %6 = load ptr, ptr @head, align 8, !tbaa !9
  store ptr %6, ptr %4, align 8, !tbaa !9
  %7 = load ptr, ptr @head, align 8, !tbaa !9
  %8 = icmp eq ptr %7, null
  br i1 %8, label %9, label %10

9:                                                ; preds = %1
  store ptr null, ptr %2, align 8
  store i32 1, ptr %5, align 4
  br label %30

10:                                               ; preds = %1
  br label %11

11:                                               ; preds = %27, %10
  %12 = load ptr, ptr %4, align 8, !tbaa !9
  %13 = getelementptr inbounds %struct.node, ptr %12, i32 0, i32 1
  %14 = load i32, ptr %13, align 4, !tbaa !11
  %15 = load i32, ptr %3, align 4, !tbaa !5
  %16 = icmp ne i32 %14, %15
  br i1 %16, label %17, label %28

17:                                               ; preds = %11
  %18 = load ptr, ptr %4, align 8, !tbaa !9
  %19 = getelementptr inbounds %struct.node, ptr %18, i32 0, i32 2
  %20 = load ptr, ptr %19, align 8, !tbaa !13
  %21 = icmp eq ptr %20, null
  br i1 %21, label %22, label %23

22:                                               ; preds = %17
  store ptr null, ptr %2, align 8
  store i32 1, ptr %5, align 4
  br label %30

23:                                               ; preds = %17
  %24 = load ptr, ptr %4, align 8, !tbaa !9
  %25 = getelementptr inbounds %struct.node, ptr %24, i32 0, i32 2
  %26 = load ptr, ptr %25, align 8, !tbaa !13
  store ptr %26, ptr %4, align 8, !tbaa !9
  br label %27

27:                                               ; preds = %23
  br label %11, !llvm.loop !14

28:                                               ; preds = %11
  %29 = load ptr, ptr %4, align 8, !tbaa !9
  store ptr %29, ptr %2, align 8
  store i32 1, ptr %5, align 4
  br label %30

30:                                               ; preds = %28, %22, %9
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #2
  %31 = load ptr, ptr %2, align 8
  ret ptr %31
}

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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !7, i64 0}
!11 = !{!12, !6, i64 4}
!12 = !{!"node", !6, i64 0, !6, i64 4, !10, i64 8}
!13 = !{!12, !10, i64 8}
!14 = distinct !{!14, !15}
!15 = !{!"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"

@head = external dso_local local_unnamed_addr global ptr, align 8

; Function Attrs: nofree norecurse nosync nounwind memory(read, inaccessiblemem: none) uwtable
define dso_local ptr @find(i32 noundef %0) local_unnamed_addr #0 {
  %2 = load ptr, ptr @head, align 8, !tbaa !5
  %3 = icmp eq ptr %2, null
  br i1 %3, label %.loopexit, label %.preheader

.preheader:                                       ; preds = %1, %6
  %.0 = phi ptr [ %8, %6 ], [ %2, %1 ]
  %4 = getelementptr inbounds i8, ptr %.0, i64 4
  %5 = load i32, ptr %4, align 4, !tbaa !9
  %.not = icmp eq i32 %5, %0
  br i1 %.not, label %.loopexit, label %6

6:                                                ; preds = %.preheader
  %7 = getelementptr inbounds i8, ptr %.0, i64 8
  %8 = load ptr, ptr %7, align 8, !tbaa !12
  %9 = icmp eq ptr %8, null
  br i1 %9, label %.loopexit, label %.preheader, !llvm.loop !13

.loopexit:                                        ; preds = %.preheader, %6, %1
  %.05 = phi ptr [ null, %1 ], [ %.0, %.preheader ], [ null, %6 ]
  ret ptr %.05
}

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, !6, i64 0}
!6 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !11, i64 4}
!10 = !{!"node", !11, i64 0, !11, i64 4, !6, i64 8}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !6, i64 8}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass