; LLVM IR from AlgoGenesis/C :: Linked_list/pairwise_swap (implementation2)

; 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: nounwind uwtable
define dso_local void @pairwiseSwap(ptr noundef %0) #0 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #2
  %5 = load ptr, ptr %2, align 8, !tbaa !5
  store ptr %5, ptr %3, align 8, !tbaa !5
  br label %6

6:                                                ; preds = %16, %1
  %7 = load ptr, ptr %3, align 8, !tbaa !5
  %8 = icmp ne ptr %7, null
  br i1 %8, label %9, label %14

9:                                                ; preds = %6
  %10 = load ptr, ptr %3, align 8, !tbaa !5
  %11 = getelementptr inbounds %struct.Node, ptr %10, i32 0, i32 1
  %12 = load ptr, ptr %11, align 8, !tbaa !9
  %13 = icmp ne ptr %12, null
  br label %14

14:                                               ; preds = %9, %6
  %15 = phi i1 [ false, %6 ], [ %13, %9 ]
  br i1 %15, label %16, label %37

16:                                               ; preds = %14
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #2
  %17 = load ptr, ptr %3, align 8, !tbaa !5
  %18 = getelementptr inbounds %struct.Node, ptr %17, i32 0, i32 0
  %19 = load i32, ptr %18, align 8, !tbaa !12
  store i32 %19, ptr %4, align 4, !tbaa !13
  %20 = load ptr, ptr %3, align 8, !tbaa !5
  %21 = getelementptr inbounds %struct.Node, ptr %20, i32 0, i32 1
  %22 = load ptr, ptr %21, align 8, !tbaa !9
  %23 = getelementptr inbounds %struct.Node, ptr %22, i32 0, i32 0
  %24 = load i32, ptr %23, align 8, !tbaa !12
  %25 = load ptr, ptr %3, align 8, !tbaa !5
  %26 = getelementptr inbounds %struct.Node, ptr %25, i32 0, i32 0
  store i32 %24, ptr %26, align 8, !tbaa !12
  %27 = load i32, ptr %4, align 4, !tbaa !13
  %28 = load ptr, ptr %3, align 8, !tbaa !5
  %29 = getelementptr inbounds %struct.Node, ptr %28, i32 0, i32 1
  %30 = load ptr, ptr %29, align 8, !tbaa !9
  %31 = getelementptr inbounds %struct.Node, ptr %30, i32 0, i32 0
  store i32 %27, ptr %31, align 8, !tbaa !12
  %32 = load ptr, ptr %3, align 8, !tbaa !5
  %33 = getelementptr inbounds %struct.Node, ptr %32, i32 0, i32 1
  %34 = load ptr, ptr %33, align 8, !tbaa !9
  %35 = getelementptr inbounds %struct.Node, ptr %34, i32 0, i32 1
  %36 = load ptr, ptr %35, align 8, !tbaa !9
  store ptr %36, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #2
  br label %6, !llvm.loop !14

37:                                               ; preds = %14
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #2
  ret void
}

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

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" }
attributes #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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, !6, i64 8}
!10 = !{!"Node", !11, i64 0, !6, i64 8}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !11, i64 0}
!13 = !{!11, !11, i64 0}
!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"

; Function Attrs: nofree norecurse nosync nounwind memory(readwrite, inaccessiblemem: none) uwtable
define dso_local void @pairwiseSwap(ptr noundef %0) local_unnamed_addr #0 {
  %.not10 = icmp eq ptr %0, null
  br i1 %.not10, label %.critedge, label %.lr.ph

.lr.ph:                                           ; preds = %1, %4
  %.011 = phi ptr [ %8, %4 ], [ %0, %1 ]
  %2 = getelementptr inbounds i8, ptr %.011, i64 8
  %3 = load ptr, ptr %2, align 8, !tbaa !5
  %.not9 = icmp eq ptr %3, null
  br i1 %.not9, label %.critedge, label %4

4:                                                ; preds = %.lr.ph
  %5 = load i32, ptr %.011, align 8, !tbaa !11
  %6 = load i32, ptr %3, align 8, !tbaa !11
  store i32 %6, ptr %.011, align 8, !tbaa !11
  store i32 %5, ptr %3, align 8, !tbaa !11
  %7 = getelementptr inbounds i8, ptr %3, i64 8
  %8 = load ptr, ptr %7, align 8, !tbaa !5
  %.not = icmp eq ptr %8, null
  br i1 %.not, label %.critedge, label %.lr.ph, !llvm.loop !12

.critedge:                                        ; preds = %.lr.ph, %4, %1
  ret void
}

attributes #0 = { nofree norecurse nosync nounwind memory(readwrite, 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 = !{!6, !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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