There is a page describing ASHWID technical details, but it is in "outdated" state - https://docs.microsoft.com/en-us/previous-versions/windows/apps/jj553431(v=win.10)?redirectedfrom=MSDN
Has the ASHWID format changed?

And a related question - can ASHWID contain more than one CPU record?

Document Details

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• ID: fc7fe9a0-1527-9b5f-e795-c1280c2d9efc
• Version Independent ID: 668c6c9d-0779-98d6-6685-064c1ed09518
• Content: HardwareIdentification Class (Windows.System.Profile) - Windows UWP applications
• Content Source: winrt-api-build/xml/Windows.System.Profile/HardwareIdentification.xml
• Product: uwp
• Technology: winrt-reference
• GitHub Login: @hickeys
• Microsoft Alias: hickeys