Re: [Qemu-devel] [PATCH] handle multibyte NOPs

[Igor Kovalenko]

On 8/21/06, malc <address@hidden> wrote:

On Mon, 21 Aug 2006, Igor Kovalenko wrote:

> On 8/19/06, Paul Brook <address@hidden> wrote:
>>
>> On Saturday 19 August 2006 00:40, Igor Kovalenko wrote:
>> > Hi!
>> >
>> > This patch adds handling of multi-byte NOPs, recent gcc/gas uses them
>> for
>> > x86 code padding.
>> > Patch checked with current opensuse-factory x86 guest installation which
>> is
>> > built with new gcc/gas tools.
>>
>> According to my amd64 documentation all of the opcodes 0f 19 through 0f 1f
>> should be implemented as a NOP. Also, I suspect the "invalid" prefetch ops
>> (0f 18) should also be implemented as nops.
>> The same implementation should be useable to all these opcodes.
>>
>>
> Updated patch, extracted noop modrm processing into separate function and
> used it for 0f 18 case as well. I also removed reg sense from noop
> processing.

Case labels in your `switch (mod)' statement are incorrect. I guess you
wanted 0x to behave like 0b, while it works for 0 and 1, for everything
else it's way of.

Right. Here is the real one with correct case labels.

-- 
Kind Regards,
Igor V. Kovalenko

x86-multibyte-noop-5.diff
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