; LLVM IR from HarshCasper/NeoAlgo :: C/ds (PairwiseSwap)

; 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 }

@header = external dso_local global ptr, align 8

; Function Attrs: nounwind uwtable
define dso_local void @pairWiseSwap() #0 {
  %1 = alloca ptr, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr %1) #2
  %2 = load ptr, ptr @header, align 8, !tbaa !5
  store ptr %2, ptr %1, align 8, !tbaa !5
  br label %3

3:                                                ; preds = %13, %0
  %4 = load ptr, ptr %1, align 8, !tbaa !5
  %5 = icmp ne ptr %4, null
  br i1 %5, label %6, label %11

6:                                                ; preds = %3
  %7 = load ptr, ptr %1, 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 ne ptr %9, null
  br label %11

11:                                               ; preds = %6, %3
  %12 = phi i1 [ false, %3 ], [ %10, %6 ]
  br i1 %12, label %13, label %25

13:                                               ; preds = %11
  %14 = load ptr, ptr %1, align 8, !tbaa !5
  %15 = getelementptr inbounds %struct.Node, ptr %14, i32 0, i32 0
  %16 = load ptr, ptr %1, align 8, !tbaa !5
  %17 = getelementptr inbounds %struct.Node, ptr %16, i32 0, i32 1
  %18 = load ptr, ptr %17, align 8, !tbaa !9
  %19 = getelementptr inbounds %struct.Node, ptr %18, i32 0, i32 0
  call void @swap(ptr noundef %15, ptr noundef %19)
  %20 = load ptr, ptr %1, 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 1
  %24 = load ptr, ptr %23, align 8, !tbaa !9
  store ptr %24, ptr %1, align 8, !tbaa !5
  br label %3, !llvm.loop !12

25:                                               ; preds = %11
  call void @llvm.lifetime.end.p0(i64 8, ptr %1) #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: nounwind uwtable
declare dso_local void @swap(ptr noundef, ptr noundef) #0

; 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 = distinct !{!12, !13}
!13 = !{!"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"

@header = external dso_local local_unnamed_addr global ptr, align 8

; Function Attrs: nounwind uwtable
define dso_local void @pairWiseSwap() local_unnamed_addr #0 {
  %.07 = load ptr, ptr @header, align 8, !tbaa !5
  %.not8 = icmp eq ptr %.07, null
  br i1 %.not8, label %.critedge, label %.lr.ph

.lr.ph:                                           ; preds = %0, %3
  %.09 = phi ptr [ %.0, %3 ], [ %.07, %0 ]
  %1 = getelementptr inbounds i8, ptr %.09, i64 8
  %2 = load ptr, ptr %1, align 8, !tbaa !9
  %.not6 = icmp eq ptr %2, null
  br i1 %.not6, label %.critedge, label %3

3:                                                ; preds = %.lr.ph
  tail call void @swap(ptr noundef nonnull %.09, ptr noundef nonnull %2)
  %4 = load ptr, ptr %1, align 8, !tbaa !9
  %5 = getelementptr inbounds i8, ptr %4, i64 8
  %.0 = load ptr, ptr %5, align 8, !tbaa !5
  %.not = icmp eq ptr %.0, null
  br i1 %.not, label %.critedge, label %.lr.ph, !llvm.loop !12

.critedge:                                        ; preds = %.lr.ph, %3, %0
  ret void
}

; Function Attrs: nounwind uwtable
declare dso_local void @swap(ptr noundef, ptr noundef) local_unnamed_addr #0

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, !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 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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