; LLVM IR from AlgoGenesis/C :: Mathematical Algorithms/Minimum Spanning Tree/Topological Sorting (Program)

; 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.Graph = type { i32, ptr, ptr }
%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: 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 @push(ptr noundef, i32 noundef) #1

; Function Attrs: nounwind uwtable
define dso_local void @dfs(ptr noundef %0, i32 noundef %1, ptr noundef %2) #1 {
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca ptr, align 8
  %7 = alloca ptr, align 8
  %8 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  store ptr %2, ptr %6, align 8, !tbaa !5
  %9 = load ptr, ptr %4, align 8, !tbaa !5
  %10 = getelementptr inbounds %struct.Graph, ptr %9, i32 0, i32 2
  %11 = load ptr, ptr %10, align 8, !tbaa !11
  %12 = load i32, ptr %5, align 4, !tbaa !9
  %13 = sext i32 %12 to i64
  %14 = getelementptr inbounds i32, ptr %11, i64 %13
  store i32 1, ptr %14, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #2
  %15 = load ptr, ptr %4, align 8, !tbaa !5
  %16 = getelementptr inbounds %struct.Graph, ptr %15, i32 0, i32 1
  %17 = load ptr, ptr %16, align 8, !tbaa !13
  %18 = load i32, ptr %5, align 4, !tbaa !9
  %19 = sext i32 %18 to i64
  %20 = getelementptr inbounds ptr, ptr %17, i64 %19
  %21 = load ptr, ptr %20, align 8, !tbaa !5
  store ptr %21, ptr %7, align 8, !tbaa !5
  br label %22

22:                                               ; preds = %41, %3
  %23 = load ptr, ptr %7, align 8, !tbaa !5
  %24 = icmp ne ptr %23, null
  br i1 %24, label %25, label %45

25:                                               ; preds = %22
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #2
  %26 = load ptr, ptr %7, align 8, !tbaa !5
  %27 = getelementptr inbounds %struct.Node, ptr %26, i32 0, i32 0
  %28 = load i32, ptr %27, align 8, !tbaa !14
  store i32 %28, ptr %8, align 4, !tbaa !9
  %29 = load ptr, ptr %4, align 8, !tbaa !5
  %30 = getelementptr inbounds %struct.Graph, ptr %29, i32 0, i32 2
  %31 = load ptr, ptr %30, align 8, !tbaa !11
  %32 = load i32, ptr %8, align 4, !tbaa !9
  %33 = sext i32 %32 to i64
  %34 = getelementptr inbounds i32, ptr %31, i64 %33
  %35 = load i32, ptr %34, align 4, !tbaa !9
  %36 = icmp eq i32 %35, 0
  br i1 %36, label %37, label %41

37:                                               ; preds = %25
  %38 = load ptr, ptr %4, align 8, !tbaa !5
  %39 = load i32, ptr %8, align 4, !tbaa !9
  %40 = load ptr, ptr %6, align 8, !tbaa !5
  call void @dfs(ptr noundef %38, i32 noundef %39, ptr noundef %40)
  br label %41

41:                                               ; preds = %37, %25
  %42 = load ptr, ptr %7, align 8, !tbaa !5
  %43 = getelementptr inbounds %struct.Node, ptr %42, i32 0, i32 1
  %44 = load ptr, ptr %43, align 8, !tbaa !16
  store ptr %44, ptr %7, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #2
  br label %22, !llvm.loop !17

45:                                               ; preds = %22
  %46 = load ptr, ptr %6, align 8, !tbaa !5
  %47 = load i32, ptr %5, align 4, !tbaa !9
  call void @push(ptr noundef %46, i32 noundef %47)
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #2
  ret void
}

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 16}
!12 = !{!"Graph", !10, i64 0, !6, i64 8, !6, i64 16}
!13 = !{!12, !6, i64 8}
!14 = !{!15, !10, i64 0}
!15 = !{!"Node", !10, i64 0, !6, i64 8}
!16 = !{!15, !6, i64 8}
!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: nounwind uwtable
declare dso_local void @push(ptr noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: nounwind uwtable
define dso_local void @dfs(ptr nocapture noundef readonly %0, i32 noundef %1, ptr noundef %2) local_unnamed_addr #0 {
  %4 = getelementptr inbounds i8, ptr %0, i64 16
  %5 = load ptr, ptr %4, align 8, !tbaa !5
  %6 = sext i32 %1 to i64
  %7 = getelementptr inbounds i32, ptr %5, i64 %6
  store i32 1, ptr %7, align 4, !tbaa !11
  %8 = getelementptr inbounds i8, ptr %0, i64 8
  %9 = load ptr, ptr %8, align 8, !tbaa !12
  %10 = getelementptr inbounds ptr, ptr %9, i64 %6
  %.013 = load ptr, ptr %10, align 8, !tbaa !13
  %.not14 = icmp eq ptr %.013, null
  br i1 %.not14, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %3, %18
  %.015 = phi ptr [ %.0, %18 ], [ %.013, %3 ]
  %11 = load i32, ptr %.015, align 8, !tbaa !14
  %12 = load ptr, ptr %4, align 8, !tbaa !5
  %13 = sext i32 %11 to i64
  %14 = getelementptr inbounds i32, ptr %12, i64 %13
  %15 = load i32, ptr %14, align 4, !tbaa !11
  %16 = icmp eq i32 %15, 0
  br i1 %16, label %17, label %18

17:                                               ; preds = %.lr.ph
  tail call void @dfs(ptr noundef nonnull %0, i32 noundef %11, ptr noundef %2)
  br label %18

18:                                               ; preds = %17, %.lr.ph
  %19 = getelementptr inbounds i8, ptr %.015, i64 8
  %.0 = load ptr, ptr %19, align 8, !tbaa !13
  %.not = icmp eq ptr %.0, null
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !16

._crit_edge:                                      ; preds = %18, %3
  tail call void @push(ptr noundef %2, i32 noundef %1)
  ret void
}

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, !10, i64 16}
!6 = !{!"Graph", !7, i64 0, !10, i64 8, !10, i64 16}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = !{!7, !7, i64 0}
!12 = !{!6, !10, i64 8}
!13 = !{!10, !10, i64 0}
!14 = !{!15, !7, i64 0}
!15 = !{!"Node", !7, i64 0, !10, i64 8}
!16 = distinct !{!16, !17}
!17 = !{!"llvm.loop.mustprogress"}


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