; LLVM IR from ahampriyanshu/algo-ds-101 :: Algorithms/Sorting/Merge_Sort_on_Doubly_Linked_List (Mergesort_doubly)

; 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, ptr }

@.str = external hidden unnamed_addr constant [38 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [40 x i8], align 1

; 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 void @print(ptr noundef %0) #1 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #3
  %4 = load ptr, ptr %2, align 8, !tbaa !5
  store ptr %4, ptr %3, align 8, !tbaa !5
  %5 = call i32 (ptr, ...) @printf(ptr noundef @.str)
  br label %6

6:                                                ; preds = %9, %1
  %7 = load ptr, ptr %2, align 8, !tbaa !5
  %8 = icmp ne ptr %7, null
  br i1 %8, label %9, label %18

9:                                                ; preds = %6
  %10 = load ptr, ptr %2, align 8, !tbaa !5
  %11 = getelementptr inbounds %struct.Node, ptr %10, i32 0, i32 0
  %12 = load i32, ptr %11, align 8, !tbaa !9
  %13 = call i32 (ptr, ...) @printf(ptr noundef @.str.1, i32 noundef %12)
  %14 = load ptr, ptr %2, align 8, !tbaa !5
  store ptr %14, ptr %3, align 8, !tbaa !5
  %15 = load ptr, ptr %2, align 8, !tbaa !5
  %16 = getelementptr inbounds %struct.Node, ptr %15, i32 0, i32 1
  %17 = load ptr, ptr %16, align 8, !tbaa !12
  store ptr %17, ptr %2, align 8, !tbaa !5
  br label %6, !llvm.loop !13

18:                                               ; preds = %6
  %19 = call i32 (ptr, ...) @printf(ptr noundef @.str.2)
  br label %20

20:                                               ; preds = %23, %18
  %21 = load ptr, ptr %3, align 8, !tbaa !5
  %22 = icmp ne ptr %21, null
  br i1 %22, label %23, label %31

23:                                               ; preds = %20
  %24 = load ptr, ptr %3, align 8, !tbaa !5
  %25 = getelementptr inbounds %struct.Node, ptr %24, i32 0, i32 0
  %26 = load i32, ptr %25, align 8, !tbaa !9
  %27 = call i32 (ptr, ...) @printf(ptr noundef @.str.1, i32 noundef %26)
  %28 = load ptr, ptr %3, align 8, !tbaa !5
  %29 = getelementptr inbounds %struct.Node, ptr %28, i32 0, i32 2
  %30 = load ptr, ptr %29, align 8, !tbaa !15
  store ptr %30, ptr %3, align 8, !tbaa !5
  br label %20, !llvm.loop !16

31:                                               ; preds = %20
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #3
  ret void
}

declare i32 @printf(ptr noundef, ...) #2

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 = { "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 #3 = { 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, !11, i64 0}
!10 = !{!"Node", !11, i64 0, !6, i64 8, !6, i64 16}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !6, i64 8}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}
!15 = !{!10, !6, i64 16}
!16 = distinct !{!16, !14}


; 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"

@.str = external hidden unnamed_addr constant [38 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [40 x i8], align 1

; Function Attrs: nofree nounwind uwtable
define dso_local void @print(ptr noundef readonly %0) local_unnamed_addr #0 {
  %2 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str)
  %.not10 = icmp eq ptr %0, null
  br i1 %.not10, label %._crit_edge.thread, label %.lr.ph

._crit_edge.thread:                               ; preds = %1
  %3 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.2)
  br label %._crit_edge16

.lr.ph:                                           ; preds = %1, %.lr.ph
  %.0811 = phi ptr [ %7, %.lr.ph ], [ %0, %1 ]
  %4 = load i32, ptr %.0811, align 8, !tbaa !5
  %5 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1, i32 noundef %4)
  %6 = getelementptr inbounds i8, ptr %.0811, i64 8
  %7 = load ptr, ptr %6, align 8, !tbaa !11
  %.not = icmp eq ptr %7, null
  br i1 %.not, label %.lr.ph15.preheader, label %.lr.ph, !llvm.loop !12

.lr.ph15.preheader:                               ; preds = %.lr.ph
  %8 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.2)
  br label %.lr.ph15

.lr.ph15:                                         ; preds = %.lr.ph15.preheader, %.lr.ph15
  %.113 = phi ptr [ %12, %.lr.ph15 ], [ %.0811, %.lr.ph15.preheader ]
  %9 = load i32, ptr %.113, align 8, !tbaa !5
  %10 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1, i32 noundef %9)
  %11 = getelementptr inbounds i8, ptr %.113, i64 16
  %12 = load ptr, ptr %11, align 8, !tbaa !14
  %.not9 = icmp eq ptr %12, null
  br i1 %.not9, label %._crit_edge16, label %.lr.ph15, !llvm.loop !15

._crit_edge16:                                    ; preds = %.lr.ph15, %._crit_edge.thread
  ret void
}

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #1

attributes #0 = { nofree 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 #1 = { nofree nounwind "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 = !{!"Node", !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 = !{!6, !10, i64 8}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}
!14 = !{!6, !10, i64 16}
!15 = distinct !{!15, !13}


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