need help with mmx (vc++)

From: Soulblazer (soulblazer28_at_yahoo.com)
Date: 07/31/04 

Date: 31 Jul 2004 11:03:39 -0700

I have a loop that I think can benefit from MMX instructions, but not
sure how to do it. I read through the manuals but nothing registers
(no pun intended).

Basically I loop through a graphics buffer (16 bit) with a right shift
and an AND operation. I've basically been loading in 32 bits and
doing two RGB's at a time, but I'm sure MMX must have a faster way.
Here is an example psuedo:

for ()
{
    int data;
    ...
    data = (data >> 1) & 0xF7F7F7F7; // 1 and 0xF7F7F7F7 are
constants
    ...
}

Can someone help translate this to an inline (MSVC) MMX version?
I would be most appreciative!

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