public override IEnumerable EnumerateMemoryRegions()

in ClrMemDiag/Desktop/runtimebase.cs [384:521]
116 lines of code
35 McCabe index (conditional complexity)

        public override IEnumerable<ClrMemoryRegion> EnumerateMemoryRegions()
        {
            // Enumerate GC Segment regions.
            IHeapDetails[] heaps;
            if (ServerGC)
            {
                heaps = new IHeapDetails[HeapCount];
                int i = 0;
                Address[] heapList = GetServerHeapList();
                if (heapList != null)
                {
                    foreach (ulong addr in heapList)
                    {
                        heaps[i++] = GetSvrHeapDetails(addr);
                        if (i == heaps.Length)
                            break;
                    }
                }
                else
                {
                    heaps = new IHeapDetails[0];
                }
            }
            else
            {
                Debug.Assert(HeapCount == 1);
                heaps = new IHeapDetails[1];
                heaps[0] = GetWksHeapDetails();
            }

            int max = 2048;  // Max number of segments in case of inconsistent data.
            for (int i = 0; i < heaps.Length; ++i)
            {
                // Small heap
                ISegmentData segment = GetSegmentData(heaps[i].FirstHeapSegment);
                while (segment != null && max-- > 0)
                {
                    Debug.Assert(segment.Start < segment.Committed);
                    Debug.Assert(segment.Committed <= segment.Reserved);

                    GCSegmentType type = (segment.Address == heaps[i].EphemeralSegment) ? GCSegmentType.Ephemeral : GCSegmentType.Regular;
                    yield return new MemoryRegion(this, segment.Start, segment.Committed - segment.Start, ClrMemoryRegionType.GCSegment, (uint)i, type);
                    yield return new MemoryRegion(this, segment.Committed, segment.Reserved - segment.Committed, ClrMemoryRegionType.ReservedGCSegment, (uint)i, type);

                    if (segment.Address == segment.Next || segment.Address == 0)
                        segment = null;
                    else
                        segment = GetSegmentData(segment.Next);
                }

                segment = GetSegmentData(heaps[i].FirstLargeHeapSegment);
                while (segment != null && max-- > 0)
                {
                    Debug.Assert(segment.Start < segment.Committed);
                    Debug.Assert(segment.Committed <= segment.Reserved);

                    yield return new MemoryRegion(this, segment.Start, segment.Committed - segment.Start, ClrMemoryRegionType.GCSegment, (uint)i, GCSegmentType.LargeObject);
                    yield return new MemoryRegion(this, segment.Committed, segment.Reserved - segment.Committed, ClrMemoryRegionType.ReservedGCSegment, (uint)i, GCSegmentType.LargeObject);

                    if (segment.Address == segment.Next || segment.Address == 0)
                        segment = null;
                    else
                        segment = GetSegmentData(segment.Next);
                }
            }

            // Enumerate handle table regions.
            HashSet<ulong> regions = new HashSet<ulong>();
            foreach (ClrHandle handle in EnumerateHandles())
            {
                VirtualQueryData vq;
                if (!_dataReader.VirtualQuery(handle.Address, out vq))
                    continue;

                if (regions.Contains(vq.BaseAddress))
                    continue;

                regions.Add(vq.BaseAddress);
                yield return new MemoryRegion(this, vq.BaseAddress, vq.Size, ClrMemoryRegionType.HandleTableChunk, handle.AppDomain);
            }

            // Enumerate each AppDomain and Module specific heap.
            AppDomainHeapWalker adhw = new AppDomainHeapWalker(this);
            IAppDomainData ad = GetAppDomainData(SystemDomainAddress);
            foreach (MemoryRegion region in adhw.EnumerateHeaps(ad))
                yield return region;

            foreach (ulong module in EnumerateModules(ad))
                foreach (MemoryRegion region in adhw.EnumerateModuleHeaps(ad, module))
                    yield return region;

            ad = GetAppDomainData(SharedDomainAddress);
            foreach (MemoryRegion region in adhw.EnumerateHeaps(ad))
                yield return region;

            foreach (ulong module in EnumerateModules(ad))
                foreach (MemoryRegion region in adhw.EnumerateModuleHeaps(ad, module))
                    yield return region;

            IAppDomainStoreData ads = GetAppDomainStoreData();
            if (ads != null)
            {
                IList<ulong> appDomains = GetAppDomainList(ads.Count);
                if (appDomains != null)
                {
                    foreach (ulong addr in appDomains)
                    {
                        ad = GetAppDomainData(addr);
                        foreach (MemoryRegion region in adhw.EnumerateHeaps(ad))
                            yield return region;

                        foreach (ulong module in EnumerateModules(ad))
                            foreach (MemoryRegion region in adhw.EnumerateModuleHeaps(ad, module))
                                yield return region;
                    }
                }
            }


            // Enumerate each JIT code heap.
            regions.Clear();
            foreach (ICodeHeap jitHeap in EnumerateJitHeaps())
            {
                if (jitHeap.Type == CodeHeapType.Host)
                {
                    VirtualQueryData vq;
                    if (_dataReader.VirtualQuery(jitHeap.Address, out vq))
                        yield return new MemoryRegion(this, vq.BaseAddress, vq.Size, ClrMemoryRegionType.JitHostCodeHeap);
                    else
                        yield return new MemoryRegion(this, jitHeap.Address, 0, ClrMemoryRegionType.JitHostCodeHeap);
                }
                else if (jitHeap.Type == CodeHeapType.Loader)
                {
                    foreach (MemoryRegion region in adhw.EnumerateJitHeap(jitHeap.Address))
                        yield return region;
                }
            }
        }