; LLVM IR from ritikbanger/Hacktoberfest2022-DSA :: 36. C Programs (single_linkedlist)

; 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 }

@.str = external hidden unnamed_addr constant [4 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [24 x i8], align 1

declare i32 @printf(ptr noundef, ...) #0

; 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

; Function Attrs: nounwind uwtable
define dso_local void @reverse(ptr noundef %0) #2 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #3
  store ptr null, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #3
  %6 = load ptr, ptr %2, align 8, !tbaa !5
  %7 = load ptr, ptr %6, align 8, !tbaa !5
  store ptr %7, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #3
  store ptr null, ptr %5, align 8, !tbaa !5
  br label %8

8:                                                ; preds = %11, %1
  %9 = load ptr, ptr %4, align 8, !tbaa !5
  %10 = icmp ne ptr %9, null
  br i1 %10, label %11, label %20

11:                                               ; preds = %8
  %12 = load ptr, ptr %4, align 8, !tbaa !5
  %13 = getelementptr inbounds %struct.node, ptr %12, i32 0, i32 1
  %14 = load ptr, ptr %13, align 8, !tbaa !9
  store ptr %14, ptr %5, align 8, !tbaa !5
  %15 = load ptr, ptr %3, align 8, !tbaa !5
  %16 = load ptr, ptr %4, align 8, !tbaa !5
  %17 = getelementptr inbounds %struct.node, ptr %16, i32 0, i32 1
  store ptr %15, ptr %17, align 8, !tbaa !9
  %18 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %18, ptr %3, align 8, !tbaa !5
  %19 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %19, ptr %4, align 8, !tbaa !5
  br label %8, !llvm.loop !12

20:                                               ; preds = %8
  %21 = load ptr, ptr %3, align 8, !tbaa !5
  %22 = load ptr, ptr %2, align 8, !tbaa !5
  store ptr %21, ptr %22, align 8, !tbaa !5
  %23 = call i32 (ptr, ...) @printf(ptr noundef @.str.4)
  br label %24

24:                                               ; preds = %27, %20
  %25 = load ptr, ptr %3, align 8, !tbaa !5
  %26 = icmp ne ptr %25, null
  br i1 %26, label %27, label %35

27:                                               ; preds = %24
  %28 = load ptr, ptr %3, align 8, !tbaa !5
  %29 = getelementptr inbounds %struct.node, ptr %28, i32 0, i32 0
  %30 = load i32, ptr %29, align 8, !tbaa !14
  %31 = call i32 (ptr, ...) @printf(ptr noundef @.str, i32 noundef %30)
  %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
  store ptr %34, ptr %3, align 8, !tbaa !5
  br label %24, !llvm.loop !15

35:                                               ; preds = %24
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #3
  ret void
}

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


; 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 [4 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [24 x i8], align 1

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #0

; Function Attrs: nofree nounwind uwtable
define dso_local void @reverse(ptr nocapture noundef %0) local_unnamed_addr #1 {
  %2 = load ptr, ptr %0, align 8, !tbaa !5
  %.not14 = icmp eq ptr %2, null
  br i1 %.not14, label %._crit_edge.thread, label %.lr.ph

._crit_edge.thread:                               ; preds = %1
  %3 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.4)
  br label %._crit_edge21

.lr.ph:                                           ; preds = %1, %.lr.ph
  %.016 = phi ptr [ %5, %.lr.ph ], [ %2, %1 ]
  %.01215 = phi ptr [ %.016, %.lr.ph ], [ null, %1 ]
  %4 = getelementptr inbounds i8, ptr %.016, i64 8
  %5 = load ptr, ptr %4, align 8, !tbaa !9
  store ptr %.01215, ptr %4, align 8, !tbaa !9
  %.not = icmp eq ptr %5, null
  br i1 %.not, label %.lr.ph20.preheader, label %.lr.ph, !llvm.loop !12

.lr.ph20.preheader:                               ; preds = %.lr.ph
  store ptr %.016, ptr %0, align 8, !tbaa !5
  %6 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.4)
  br label %.lr.ph20

.lr.ph20:                                         ; preds = %.lr.ph20.preheader, %.lr.ph20
  %.118 = phi ptr [ %10, %.lr.ph20 ], [ %.016, %.lr.ph20.preheader ]
  %7 = load i32, ptr %.118, align 8, !tbaa !14
  %8 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str, i32 noundef %7)
  %9 = getelementptr inbounds i8, ptr %.118, i64 8
  %10 = load ptr, ptr %9, align 8, !tbaa !9
  %.not13 = icmp eq ptr %10, null
  br i1 %.not13, label %._crit_edge21, label %.lr.ph20, !llvm.loop !15

._crit_edge21:                                    ; preds = %.lr.ph20, %._crit_edge.thread
  ret void
}

attributes #0 = { 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" }
attributes #1 = { 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" }

!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"}
!14 = !{!10, !11, i64 0}
!15 = distinct !{!15, !13}


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