; LLVM IR from elarity/data-structure-php-clanguage :: clang.single-link-list (read_node)

; 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: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nounwind uwtable
define dso_local i32 @read_node(ptr noundef %0, i32 noundef %1) #1 {
  %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
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  %8 = load i32, ptr %5, align 4, !tbaa !9
  %9 = icmp slt i32 %8, 1
  br i1 %9, label %10, label %11

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

11:                                               ; preds = %2
  %12 = load ptr, ptr %4, align 8, !tbaa !5
  %13 = getelementptr inbounds %struct.node, ptr %12, i32 0, i32 1
  %14 = load ptr, ptr %13, align 8, !tbaa !11
  store ptr %14, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  store i32 1, ptr %6, align 4, !tbaa !9
  br label %15

15:                                               ; preds = %24, %11
  %16 = load ptr, ptr %4, align 8, !tbaa !5
  %17 = icmp ne ptr %16, null
  br i1 %17, label %18, label %22

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

22:                                               ; preds = %18, %15
  %23 = phi i1 [ false, %15 ], [ %21, %18 ]
  br i1 %23, label %24, label %30

24:                                               ; preds = %22
  %25 = load ptr, ptr %4, align 8, !tbaa !5
  %26 = getelementptr inbounds %struct.node, ptr %25, i32 0, i32 1
  %27 = load ptr, ptr %26, align 8, !tbaa !11
  store ptr %27, ptr %4, align 8, !tbaa !5
  %28 = load i32, ptr %6, align 4, !tbaa !9
  %29 = add nsw i32 %28, 1
  store i32 %29, ptr %6, align 4, !tbaa !9
  br label %15, !llvm.loop !13

30:                                               ; preds = %22
  %31 = load ptr, ptr %4, align 8, !tbaa !5
  %32 = icmp eq ptr null, %31
  br i1 %32, label %33, label %34

33:                                               ; preds = %30
  store i32 -1, ptr %3, align 4
  store i32 1, ptr %7, align 4
  br label %38

34:                                               ; preds = %30
  %35 = load ptr, ptr %4, align 8, !tbaa !5
  %36 = getelementptr inbounds %struct.node, ptr %35, i32 0, i32 0
  %37 = load i32, ptr %36, align 8, !tbaa !15
  store i32 %37, ptr %3, align 4
  store i32 1, ptr %7, align 4
  br label %38

38:                                               ; preds = %34, %33
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  br label %39

39:                                               ; preds = %38, %10
  %40 = load i32, ptr %3, align 4
  ret i32 %40
}

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

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 = !{!"node", !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: nofree norecurse nosync nounwind memory(read, inaccessiblemem: none) uwtable
define dso_local i32 @read_node(ptr nocapture noundef readonly %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = icmp slt i32 %1, 1
  br i1 %3, label %12, label %.preheader

.preheader:                                       ; preds = %2, %.preheader
  %.pn = phi ptr [ %.010, %.preheader ], [ %0, %2 ]
  %.0 = phi i32 [ %7, %.preheader ], [ 1, %2 ]
  %.010.in = getelementptr inbounds i8, ptr %.pn, i64 8
  %.010 = load ptr, ptr %.010.in, align 8, !tbaa !5
  %4 = icmp ne ptr %.010, null
  %5 = icmp slt i32 %.0, %1
  %6 = select i1 %4, i1 %5, i1 false
  %7 = add nuw nsw i32 %.0, 1
  br i1 %6, label %.preheader, label %8, !llvm.loop !11

8:                                                ; preds = %.preheader
  %9 = icmp eq ptr %.010, null
  br i1 %9, label %12, label %10

10:                                               ; preds = %8
  %11 = load i32, ptr %.010, align 8, !tbaa !13
  br label %12

12:                                               ; preds = %10, %8, %2
  %.1 = phi i32 [ -1, %2 ], [ %11, %10 ], [ -1, %8 ]
  ret i32 %.1
}

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


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass