Re: [RFC PATCH 0/6] jump label v3

[H. Peter Anvin]

On 11/18/2009 02:43 PM, Jason Baron wrote:
> 
> I'm using an atomic 5 byte no-op for x86_64 and a long jump for 32-bit x86.
> My understanding is that not all 32-bit processors have an atomic 5 byte no-op,
> and thus using a long jump or jump 0, for the off case is the safest.
> 

67 66 8D 74 00 (lea si,[si+0]) should work as a 32-bit atomic NOP.  It's
not necessarily the fastest, though (I have no data on that.)
Similarly, 66 66 66 66 90 should also work.

	-hpa
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