Re: xchg & lock question

For those, who may also being interesting in this topic,
the answer is as follows.

These are e.g. Pentium 4, Intel Xeon, and P6 family processors.
For them, if the memory area being accessed is cached internally
in the processor, the LOCK# signal is generally not asserted;
instead, locking is only applied to the processor's caches.
("IA-32 IntelR Architecture Software Developer's Manual,
Volume 3: System Programming Guide").

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"Eman" <spamtrap@xxxxxxxxxx> wrote in message news:e06vfn$2dlm$2@xxxxxxxxxxxxxxxxx
According to Intel' manual "when a memory operand is used with the XCHG instruction, the processor's LOCK signal is automatically
asserted". AMD documentation also states that.

Can someone tell me, which of IA32 compatible processors do not
assert LOCK automatically in the case of XCHG reg,[mem] ?

Thanks in advance.

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Relevant Pages

  • Re: xchg & lock question
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  • Re: xchg & lock question
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