message: Don't run shader feedback if there's no root signature bound
diff: @@ -328,6 +328,10 @@ void D3D12Replay::FetchShaderFeedback(uint32_t eventId)
  if(result.compute)
  {
  ID3D12RootSignature *sig = rm->GetCurrentAs<ID3D12RootSignature>(rs.compute.rootsig);
  +
  + if(!sig)
  + return;
  +
  modsig = ((WrappedID3D12RootSignature *)sig)->sig;
  space = modsig.maxSpaceIndex;
  @@ -337,6 +341,10 @@ void D3D12Replay::FetchShaderFeedback(uint32_t eventId)
  else
  {
  ID3D12RootSignature *sig = rm->GetCurrentAs<ID3D12RootSignature>(rs.graphics.rootsig);
  +
  + if(!sig)
  + return;
  +
  modsig = ((WrappedID3D12RootSignature *)sig)->sig;
  space = modsig.maxSpaceIndex;
  