; LLVM IR from begeekmyfriend/leetcode :: 0021_merge_two_sorted_lists (merge_lists)

; 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.ListNode = type { i32, ptr }

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

; Function Attrs: nounwind uwtable
define dso_local i32 @main(i32 noundef %0, ptr noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca ptr, align 8
  %6 = alloca %struct.ListNode, align 8
  %7 = alloca %struct.ListNode, align 8
  %8 = alloca ptr, align 8
  store i32 0, ptr %3, align 4
  store i32 %0, ptr %4, align 4, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 16, ptr %6) #3
  %9 = getelementptr inbounds %struct.ListNode, ptr %6, i32 0, i32 0
  store i32 2, ptr %9, align 8, !tbaa !11
  %10 = getelementptr inbounds %struct.ListNode, ptr %6, i32 0, i32 1
  store ptr null, ptr %10, align 8, !tbaa !13
  call void @llvm.lifetime.start.p0(i64 16, ptr %7) #3
  %11 = getelementptr inbounds %struct.ListNode, ptr %7, i32 0, i32 0
  store i32 1, ptr %11, align 8, !tbaa !11
  %12 = getelementptr inbounds %struct.ListNode, ptr %7, i32 0, i32 1
  store ptr null, ptr %12, align 8, !tbaa !13
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #3
  %13 = call ptr @mergeTwoLists(ptr noundef %6, ptr noundef %7)
  store ptr %13, ptr %8, align 8, !tbaa !9
  br label %14

14:                                               ; preds = %17, %2
  %15 = load ptr, ptr %8, align 8, !tbaa !9
  %16 = icmp ne ptr %15, null
  br i1 %16, label %17, label %25

17:                                               ; preds = %14
  %18 = load ptr, ptr %8, align 8, !tbaa !9
  %19 = getelementptr inbounds %struct.ListNode, ptr %18, i32 0, i32 0
  %20 = load i32, ptr %19, align 8, !tbaa !11
  %21 = call i32 (ptr, ...) @printf(ptr noundef @.str, i32 noundef %20)
  %22 = load ptr, ptr %8, align 8, !tbaa !9
  %23 = getelementptr inbounds %struct.ListNode, ptr %22, i32 0, i32 1
  %24 = load ptr, ptr %23, align 8, !tbaa !13
  store ptr %24, ptr %8, align 8, !tbaa !9
  br label %14, !llvm.loop !14

25:                                               ; preds = %14
  %26 = call i32 (ptr, ...) @printf(ptr noundef @.str.1)
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #3
  call void @llvm.lifetime.end.p0(i64 16, ptr %7) #3
  call void @llvm.lifetime.end.p0(i64 16, ptr %6) #3
  ret i32 0
}

; 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 hidden ptr @mergeTwoLists(ptr noundef, ptr noundef) #0

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

; 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 = { "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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !7, i64 0}
!11 = !{!12, !6, i64 0}
!12 = !{!"ListNode", !6, i64 0, !10, i64 8}
!13 = !{!12, !10, i64 8}
!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"

%struct.ListNode = type { i32, ptr }

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

; Function Attrs: nounwind uwtable
define dso_local noundef i32 @main(i32 noundef %0, ptr nocapture noundef readnone %1) local_unnamed_addr #0 {
  %3 = alloca %struct.ListNode, align 8
  %4 = alloca %struct.ListNode, align 8
  call void @llvm.lifetime.start.p0(i64 16, ptr nonnull %3) #3
  store i32 2, ptr %3, align 8, !tbaa !5
  %5 = getelementptr inbounds i8, ptr %3, i64 8
  store ptr null, ptr %5, align 8, !tbaa !11
  call void @llvm.lifetime.start.p0(i64 16, ptr nonnull %4) #3
  store i32 1, ptr %4, align 8, !tbaa !5
  %6 = getelementptr inbounds i8, ptr %4, i64 8
  store ptr null, ptr %6, align 8, !tbaa !11
  %7 = call ptr @mergeTwoLists(ptr noundef nonnull %3, ptr noundef nonnull %4)
  %.not3 = icmp eq ptr %7, null
  br i1 %.not3, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %2, %.lr.ph
  %.04 = phi ptr [ %11, %.lr.ph ], [ %7, %2 ]
  %8 = load i32, ptr %.04, align 8, !tbaa !5
  %9 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str, i32 noundef %8)
  %10 = getelementptr inbounds i8, ptr %.04, i64 8
  %11 = load ptr, ptr %10, align 8, !tbaa !11
  %.not = icmp eq ptr %11, null
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !12

._crit_edge:                                      ; preds = %.lr.ph, %2
  %12 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1)
  call void @llvm.lifetime.end.p0(i64 16, ptr nonnull %4) #3
  call void @llvm.lifetime.end.p0(i64 16, ptr nonnull %3) #3
  ret i32 0
}

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

; Function Attrs: nounwind uwtable
declare hidden ptr @mergeTwoLists(ptr noundef, ptr noundef) local_unnamed_addr #0

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

; Function Attrs: mustprogress 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 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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 #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, !7, i64 0}
!6 = !{!"ListNode", !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, !10, i64 8}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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