; LLVM IR from div-bargali/Data-Structures-and-Algorithms :: C++/Data-Structures/LinkedList/Flatten_List.ll (Z7flattenP4Node)

; 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 }

; Function Attrs: mustprogress uwtable
define dso_local noundef ptr @_Z7flattenP4Node(ptr noundef %0) #0 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  store ptr %0, ptr %3, align 8, !tbaa !5
  %4 = load ptr, ptr %3, align 8, !tbaa !5
  %5 = icmp eq ptr %4, null
  br i1 %5, label %11, label %6

6:                                                ; preds = %1
  %7 = load ptr, ptr %3, align 8, !tbaa !5
  %8 = getelementptr inbounds %struct.Node, ptr %7, i32 0, i32 1
  %9 = load ptr, ptr %8, align 8, !tbaa !9
  %10 = icmp eq ptr %9, null
  br i1 %10, label %11, label %13

11:                                               ; preds = %6, %1
  %12 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %12, ptr %2, align 8
  br label %20

13:                                               ; preds = %6
  %14 = load ptr, ptr %3, align 8, !tbaa !5
  %15 = load ptr, ptr %3, align 8, !tbaa !5
  %16 = getelementptr inbounds %struct.Node, ptr %15, i32 0, i32 1
  %17 = load ptr, ptr %16, align 8, !tbaa !9
  %18 = call noundef ptr @_Z7flattenP4Node(ptr noundef %17)
  %19 = call noundef ptr @_Z5mergeP4NodeS0_(ptr noundef %14, ptr noundef %18)
  store ptr %19, ptr %2, align 8
  br label %20

20:                                               ; preds = %13, %11
  %21 = load ptr, ptr %2, align 8
  ret ptr %21
}

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_Z5mergeP4NodeS0_(ptr noundef, ptr noundef) #0

attributes #0 = { mustprogress 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++ TBAA"}
!9 = !{!10, !6, i64 8}
!10 = !{!"_ZTS4Node", !11, i64 0, !6, i64 8, !6, i64 16}
!11 = !{!"int", !7, 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: mustprogress uwtable
define dso_local noundef ptr @_Z7flattenP4Node(ptr noundef %0) local_unnamed_addr #0 {
  %2 = icmp eq ptr %0, null
  br i1 %2, label %common.ret8, label %3

3:                                                ; preds = %1
  %4 = getelementptr inbounds i8, ptr %0, i64 8
  %5 = load ptr, ptr %4, align 8, !tbaa !5
  %6 = icmp eq ptr %5, null
  br i1 %6, label %common.ret8, label %7

common.ret8:                                      ; preds = %1, %3, %7
  %common.ret8.op = phi ptr [ %9, %7 ], [ %0, %3 ], [ null, %1 ]
  ret ptr %common.ret8.op

7:                                                ; preds = %3
  %8 = tail call noundef ptr @_Z7flattenP4Node(ptr noundef nonnull %5)
  %9 = tail call noundef ptr @_Z5mergeP4NodeS0_(ptr noundef nonnull %0, ptr noundef %8)
  br label %common.ret8
}

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_Z5mergeP4NodeS0_(ptr noundef, ptr noundef) local_unnamed_addr #0

attributes #0 = { mustprogress 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 = !{!"_ZTS4Node", !7, i64 0, !10, i64 8, !10, i64 16}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}


; Effective O3 passes: CorrelatedValuePropagationPass,EarlyCSEPass,GlobalOptPass,InstCombinePass,SROAPass,SimplifyCFGPass,TailCallElimPass