inline HRESULT D3DX12SerializeVersionedRootSignature()

in Python/src/d3dx12.h [2056:2169]
100 lines of code
26 McCabe index (conditional complexity)

inline HRESULT D3DX12SerializeVersionedRootSignature(
    _In_ const D3D12_VERSIONED_ROOT_SIGNATURE_DESC* pRootSignatureDesc,
    D3D_ROOT_SIGNATURE_VERSION MaxVersion,
    _Outptr_ ID3DBlob** ppBlob,
    _Always_(_Outptr_opt_result_maybenull_) ID3DBlob** ppErrorBlob)
{
    if (ppErrorBlob != nullptr)
    {
        *ppErrorBlob = nullptr;
    }

    switch (MaxVersion)
    {
    case D3D_ROOT_SIGNATURE_VERSION_1_0:
        switch (pRootSignatureDesc->Version)
        {
        case D3D_ROOT_SIGNATURE_VERSION_1_0:
            return D3D12SerializeRootSignature(&pRootSignatureDesc->Desc_1_0, D3D_ROOT_SIGNATURE_VERSION_1, ppBlob, ppErrorBlob);

        case D3D_ROOT_SIGNATURE_VERSION_1_1:
        {
            HRESULT hr = S_OK;
            const D3D12_ROOT_SIGNATURE_DESC1& desc_1_1 = pRootSignatureDesc->Desc_1_1;

            const SIZE_T ParametersSize = sizeof(D3D12_ROOT_PARAMETER) * desc_1_1.NumParameters;
            void* pParameters = (ParametersSize > 0) ? HeapAlloc(GetProcessHeap(), 0, ParametersSize) : nullptr;
            if (ParametersSize > 0 && pParameters == nullptr)
            {
                hr = E_OUTOFMEMORY;
            }
            auto pParameters_1_0 = reinterpret_cast<D3D12_ROOT_PARAMETER*>(pParameters);

            if (SUCCEEDED(hr))
            {
                for (UINT n = 0; n < desc_1_1.NumParameters; n++)
                {
                    __analysis_assume(ParametersSize == sizeof(D3D12_ROOT_PARAMETER) * desc_1_1.NumParameters);
                    pParameters_1_0[n].ParameterType = desc_1_1.pParameters[n].ParameterType;
                    pParameters_1_0[n].ShaderVisibility = desc_1_1.pParameters[n].ShaderVisibility;

                    switch (desc_1_1.pParameters[n].ParameterType)
                    {
                    case D3D12_ROOT_PARAMETER_TYPE_32BIT_CONSTANTS:
                        pParameters_1_0[n].Constants.Num32BitValues = desc_1_1.pParameters[n].Constants.Num32BitValues;
                        pParameters_1_0[n].Constants.RegisterSpace = desc_1_1.pParameters[n].Constants.RegisterSpace;
                        pParameters_1_0[n].Constants.ShaderRegister = desc_1_1.pParameters[n].Constants.ShaderRegister;
                        break;

                    case D3D12_ROOT_PARAMETER_TYPE_CBV:
                    case D3D12_ROOT_PARAMETER_TYPE_SRV:
                    case D3D12_ROOT_PARAMETER_TYPE_UAV:
                        pParameters_1_0[n].Descriptor.RegisterSpace = desc_1_1.pParameters[n].Descriptor.RegisterSpace;
                        pParameters_1_0[n].Descriptor.ShaderRegister = desc_1_1.pParameters[n].Descriptor.ShaderRegister;
                        break;

                    case D3D12_ROOT_PARAMETER_TYPE_DESCRIPTOR_TABLE:
                        const D3D12_ROOT_DESCRIPTOR_TABLE1& table_1_1 = desc_1_1.pParameters[n].DescriptorTable;

                        const SIZE_T DescriptorRangesSize = sizeof(D3D12_DESCRIPTOR_RANGE) * table_1_1.NumDescriptorRanges;
                        void* pDescriptorRanges = (DescriptorRangesSize > 0 && SUCCEEDED(hr)) ? HeapAlloc(GetProcessHeap(), 0, DescriptorRangesSize) : nullptr;
                        if (DescriptorRangesSize > 0 && pDescriptorRanges == nullptr)
                        {
                            hr = E_OUTOFMEMORY;
                        }
                        auto pDescriptorRanges_1_0 = reinterpret_cast<D3D12_DESCRIPTOR_RANGE*>(pDescriptorRanges);

                        if (SUCCEEDED(hr))
                        {
                            for (UINT x = 0; x < table_1_1.NumDescriptorRanges; x++)
                            {
                                __analysis_assume(DescriptorRangesSize == sizeof(D3D12_DESCRIPTOR_RANGE) * table_1_1.NumDescriptorRanges);
                                pDescriptorRanges_1_0[x].BaseShaderRegister = table_1_1.pDescriptorRanges[x].BaseShaderRegister;
                                pDescriptorRanges_1_0[x].NumDescriptors = table_1_1.pDescriptorRanges[x].NumDescriptors;
                                pDescriptorRanges_1_0[x].OffsetInDescriptorsFromTableStart = table_1_1.pDescriptorRanges[x].OffsetInDescriptorsFromTableStart;
                                pDescriptorRanges_1_0[x].RangeType = table_1_1.pDescriptorRanges[x].RangeType;
                                pDescriptorRanges_1_0[x].RegisterSpace = table_1_1.pDescriptorRanges[x].RegisterSpace;
                            }
                        }

                        D3D12_ROOT_DESCRIPTOR_TABLE& table_1_0 = pParameters_1_0[n].DescriptorTable;
                        table_1_0.NumDescriptorRanges = table_1_1.NumDescriptorRanges;
                        table_1_0.pDescriptorRanges = pDescriptorRanges_1_0;
                    }
                }
            }

            if (SUCCEEDED(hr))
            {
                CD3DX12_ROOT_SIGNATURE_DESC desc_1_0(desc_1_1.NumParameters, pParameters_1_0, desc_1_1.NumStaticSamplers, desc_1_1.pStaticSamplers, desc_1_1.Flags);
                hr = D3D12SerializeRootSignature(&desc_1_0, D3D_ROOT_SIGNATURE_VERSION_1, ppBlob, ppErrorBlob);
            }

            if (pParameters)
            {
                for (UINT n = 0; n < desc_1_1.NumParameters; n++)
                {
                    if (desc_1_1.pParameters[n].ParameterType == D3D12_ROOT_PARAMETER_TYPE_DESCRIPTOR_TABLE)
                    {
                        HeapFree(GetProcessHeap(), 0, reinterpret_cast<void*>(const_cast<D3D12_DESCRIPTOR_RANGE*>(pParameters_1_0[n].DescriptorTable.pDescriptorRanges)));
                    }
                }
                HeapFree(GetProcessHeap(), 0, pParameters);
            }
            return hr;
        }
        }
        break;

    case D3D_ROOT_SIGNATURE_VERSION_1_1:
        return D3D12SerializeVersionedRootSignature(pRootSignatureDesc, ppBlob, ppErrorBlob);
    }

    return E_INVALIDARG;
}