[PATCH] x86: Only use general-purpose registers during CPUID check

Florian Weimer fw@deneb.enyo.de
Sun Aug 23 21:22:00 GMT 2020

* H. J. Lu via Gcc-patches:

> 2. CPUID check should be done with general registers only.

Is this really the concern here?  Isn't this about instructions, not
registers?  If there's a useful integer register instruction for
post-processing CPUID bits that's not in the baseline ABI, GCC still
shouldn't use it in the check, I assume.

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