; LLVM IR from yourtion/LearningMasteringAlgorithms-C :: source (dlist)

; 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.DList_ = type { i32, ptr, ptr, ptr, ptr }
%struct.DListElmt_ = type { ptr, ptr, ptr }

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nounwind allocsize(0)
declare noalias ptr @malloc(i64 noundef) #1

; Function Attrs: nounwind uwtable
define dso_local i32 @dlist_ins_prev(ptr noundef %0, ptr noundef %1, ptr noundef %2) #2 {
  %4 = alloca i32, align 4
  %5 = alloca ptr, align 8
  %6 = alloca ptr, align 8
  %7 = alloca ptr, align 8
  %8 = alloca ptr, align 8
  %9 = alloca i32, align 4
  store ptr %0, ptr %5, align 8, !tbaa !5
  store ptr %1, ptr %6, align 8, !tbaa !5
  store ptr %2, ptr %7, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #3
  %10 = load ptr, ptr %6, align 8, !tbaa !5
  %11 = icmp eq ptr %10, null
  br i1 %11, label %12, label %18

12:                                               ; preds = %3
  %13 = load ptr, ptr %5, align 8, !tbaa !5
  %14 = getelementptr inbounds %struct.DList_, ptr %13, i32 0, i32 0
  %15 = load i32, ptr %14, align 8, !tbaa !9
  %16 = icmp ne i32 %15, 0
  br i1 %16, label %17, label %18

17:                                               ; preds = %12
  store i32 -1, ptr %4, align 4
  store i32 1, ptr %9, align 4
  br label %77

18:                                               ; preds = %12, %3
  %19 = call noalias ptr @malloc(i64 noundef 24) #4
  store ptr %19, ptr %8, align 8, !tbaa !5
  %20 = icmp eq ptr %19, null
  br i1 %20, label %21, label %22

21:                                               ; preds = %18
  store i32 -1, ptr %4, align 4
  store i32 1, ptr %9, align 4
  br label %77

22:                                               ; preds = %18
  %23 = load ptr, ptr %7, align 8, !tbaa !5
  %24 = load ptr, ptr %8, align 8, !tbaa !5
  %25 = getelementptr inbounds %struct.DListElmt_, ptr %24, i32 0, i32 0
  store ptr %23, ptr %25, align 8, !tbaa !12
  %26 = load ptr, ptr %5, align 8, !tbaa !5
  %27 = getelementptr inbounds %struct.DList_, ptr %26, i32 0, i32 0
  %28 = load i32, ptr %27, align 8, !tbaa !9
  %29 = icmp eq i32 %28, 0
  br i1 %29, label %30, label %45

30:                                               ; preds = %22
  %31 = load ptr, ptr %8, align 8, !tbaa !5
  %32 = load ptr, ptr %5, align 8, !tbaa !5
  %33 = getelementptr inbounds %struct.DList_, ptr %32, i32 0, i32 3
  store ptr %31, ptr %33, align 8, !tbaa !14
  %34 = load ptr, ptr %5, align 8, !tbaa !5
  %35 = getelementptr inbounds %struct.DList_, ptr %34, i32 0, i32 3
  %36 = load ptr, ptr %35, align 8, !tbaa !14
  %37 = getelementptr inbounds %struct.DListElmt_, ptr %36, i32 0, i32 1
  store ptr null, ptr %37, align 8, !tbaa !15
  %38 = load ptr, ptr %5, align 8, !tbaa !5
  %39 = getelementptr inbounds %struct.DList_, ptr %38, i32 0, i32 3
  %40 = load ptr, ptr %39, align 8, !tbaa !14
  %41 = getelementptr inbounds %struct.DListElmt_, ptr %40, i32 0, i32 2
  store ptr null, ptr %41, align 8, !tbaa !16
  %42 = load ptr, ptr %8, align 8, !tbaa !5
  %43 = load ptr, ptr %5, align 8, !tbaa !5
  %44 = getelementptr inbounds %struct.DList_, ptr %43, i32 0, i32 4
  store ptr %42, ptr %44, align 8, !tbaa !17
  br label %72

45:                                               ; preds = %22
  %46 = load ptr, ptr %6, align 8, !tbaa !5
  %47 = load ptr, ptr %8, align 8, !tbaa !5
  %48 = getelementptr inbounds %struct.DListElmt_, ptr %47, i32 0, i32 2
  store ptr %46, ptr %48, align 8, !tbaa !16
  %49 = load ptr, ptr %6, align 8, !tbaa !5
  %50 = getelementptr inbounds %struct.DListElmt_, ptr %49, i32 0, i32 1
  %51 = load ptr, ptr %50, align 8, !tbaa !15
  %52 = load ptr, ptr %8, align 8, !tbaa !5
  %53 = getelementptr inbounds %struct.DListElmt_, ptr %52, i32 0, i32 1
  store ptr %51, ptr %53, align 8, !tbaa !15
  %54 = load ptr, ptr %6, align 8, !tbaa !5
  %55 = getelementptr inbounds %struct.DListElmt_, ptr %54, i32 0, i32 1
  %56 = load ptr, ptr %55, align 8, !tbaa !15
  %57 = icmp eq ptr %56, null
  br i1 %57, label %58, label %62

58:                                               ; preds = %45
  %59 = load ptr, ptr %8, align 8, !tbaa !5
  %60 = load ptr, ptr %5, align 8, !tbaa !5
  %61 = getelementptr inbounds %struct.DList_, ptr %60, i32 0, i32 3
  store ptr %59, ptr %61, align 8, !tbaa !14
  br label %68

62:                                               ; preds = %45
  %63 = load ptr, ptr %8, align 8, !tbaa !5
  %64 = load ptr, ptr %6, align 8, !tbaa !5
  %65 = getelementptr inbounds %struct.DListElmt_, ptr %64, i32 0, i32 1
  %66 = load ptr, ptr %65, align 8, !tbaa !15
  %67 = getelementptr inbounds %struct.DListElmt_, ptr %66, i32 0, i32 2
  store ptr %63, ptr %67, align 8, !tbaa !16
  br label %68

68:                                               ; preds = %62, %58
  %69 = load ptr, ptr %8, align 8, !tbaa !5
  %70 = load ptr, ptr %6, align 8, !tbaa !5
  %71 = getelementptr inbounds %struct.DListElmt_, ptr %70, i32 0, i32 1
  store ptr %69, ptr %71, align 8, !tbaa !15
  br label %72

72:                                               ; preds = %68, %30
  %73 = load ptr, ptr %5, align 8, !tbaa !5
  %74 = getelementptr inbounds %struct.DList_, ptr %73, i32 0, i32 0
  %75 = load i32, ptr %74, align 8, !tbaa !9
  %76 = add nsw i32 %75, 1
  store i32 %76, ptr %74, align 8, !tbaa !9
  store i32 0, ptr %4, align 4
  store i32 1, ptr %9, align 4
  br label %77

77:                                               ; preds = %72, %21, %17
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #3
  %78 = load i32, ptr %4, align 4
  ret i32 %78
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { nounwind allocsize(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 #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 }
attributes #4 = { nounwind allocsize(0) }

!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, !11, i64 0}
!10 = !{!"DList_", !11, i64 0, !6, i64 8, !6, i64 16, !6, i64 24, !6, i64 32}
!11 = !{!"int", !7, i64 0}
!12 = !{!13, !6, i64 0}
!13 = !{!"DListElmt_", !6, i64 0, !6, i64 8, !6, i64 16}
!14 = !{!10, !6, i64 24}
!15 = !{!13, !6, i64 8}
!16 = !{!13, !6, i64 16}
!17 = !{!10, !6, i64 32}


; 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 nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite)
declare noalias noundef ptr @malloc(i64 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nofree nounwind willreturn memory(write, argmem: readwrite, inaccessiblemem: readwrite) uwtable
define dso_local range(i32 -1, 1) i32 @dlist_ins_prev(ptr nocapture noundef %0, ptr noundef %1, ptr noundef %2) local_unnamed_addr #1 {
  %4 = icmp eq ptr %1, null
  br i1 %4, label %5, label %7

5:                                                ; preds = %3
  %6 = load i32, ptr %0, align 8, !tbaa !5
  %.not = icmp eq i32 %6, 0
  br i1 %.not, label %7, label %27

7:                                                ; preds = %5, %3
  %8 = tail call noalias dereferenceable_or_null(24) ptr @malloc(i64 noundef 24) #3
  %9 = icmp eq ptr %8, null
  br i1 %9, label %27, label %10

10:                                               ; preds = %7
  store ptr %2, ptr %8, align 8, !tbaa !11
  %11 = load i32, ptr %0, align 8, !tbaa !5
  %12 = icmp eq i32 %11, 0
  br i1 %12, label %13, label %17

13:                                               ; preds = %10
  %14 = getelementptr inbounds i8, ptr %0, i64 24
  store ptr %8, ptr %14, align 8, !tbaa !13
  %15 = getelementptr inbounds i8, ptr %8, i64 8
  %16 = getelementptr inbounds i8, ptr %0, i64 32
  tail call void @llvm.memset.p0.i64(ptr noundef nonnull align 8 dereferenceable(16) %15, i8 0, i64 16, i1 false)
  br label %25

17:                                               ; preds = %10
  %18 = getelementptr inbounds i8, ptr %8, i64 16
  store ptr %1, ptr %18, align 8, !tbaa !14
  %19 = getelementptr inbounds i8, ptr %1, i64 8
  %20 = load ptr, ptr %19, align 8, !tbaa !15
  %21 = getelementptr inbounds i8, ptr %8, i64 8
  store ptr %20, ptr %21, align 8, !tbaa !15
  %22 = icmp eq ptr %20, null
  %23 = getelementptr inbounds i8, ptr %20, i64 16
  %24 = getelementptr inbounds i8, ptr %0, i64 24
  %.sink = select i1 %22, ptr %24, ptr %23
  store ptr %8, ptr %.sink, align 8, !tbaa !16
  br label %25

25:                                               ; preds = %17, %13
  %.sink25 = phi ptr [ %19, %17 ], [ %16, %13 ]
  store ptr %8, ptr %.sink25, align 8, !tbaa !16
  %26 = add nsw i32 %11, 1
  store i32 %26, ptr %0, align 8, !tbaa !5
  br label %27

27:                                               ; preds = %7, %5, %25
  %.0 = phi i32 [ 0, %25 ], [ -1, %5 ], [ -1, %7 ]
  ret i32 %.0
}

; Function Attrs: nocallback nofree nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #2

attributes #0 = { mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite) "alloc-family"="malloc" "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 nofree nounwind willreturn memory(write, argmem: readwrite, inaccessiblemem: readwrite) 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 #2 = { nocallback nofree nounwind willreturn memory(argmem: write) }
attributes #3 = { nounwind allocsize(0) }

!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 = !{!"DList_", !7, i64 0, !10, i64 8, !10, i64 16, !10, i64 24, !10, i64 32}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = !{!12, !10, i64 0}
!12 = !{!"DListElmt_", !10, i64 0, !10, i64 8, !10, i64 16}
!13 = !{!6, !10, i64 24}
!14 = !{!12, !10, i64 16}
!15 = !{!12, !10, i64 8}
!16 = !{!10, !10, i64 0}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,IPSCCPPass,InferFunctionAttrsPass,InstCombinePass,MemCpyOptPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass