How to override CPUID information?

I need to override CPUID information in a VM to run some old OSs. Is there a way to do that in Parallels Desktop for Mac?

VirtualBox has a --cpuidset option for its VBoxManage modifyvm command which adds a CpuIdLeaf to CpuIdTree in the VirtualBox VM's vbox file.

In the Parallels VM's config.pvs file, I see stuff like the following but I don't think it does anything?

Code:

            <FEATURES_MASK>529267711</FEATURES_MASK>
            <EXT_FEATURES_MASK>4160369163</EXT_FEATURES_MASK>
            <EXT_80000001_ECX_MASK>289</EXT_80000001_ECX_MASK>
            <EXT_80000001_EDX_MASK>672139264</EXT_80000001_EDX_MASK>
            <EXT_80000007_EDX_MASK>256</EXT_80000007_EDX_MASK>
            <EXT_80000008_EAX>12324</EXT_80000008_EAX>
            <EXT_00000007_EBX_MASK>9177003</EXT_00000007_EBX_MASK>
            <EXT_00000007_EDX_MASK>0</EXT_00000007_EDX_MASK>
            <EXT_0000000D_EAX_MASK>3</EXT_0000000D_EAX_MASK>
            <EXT_00000006_EAX_MASK>85</EXT_00000006_EAX_MASK>
            <CpuFeaturesMaskValid>1</CpuFeaturesMaskValid>