Multi-use register clobbering.

[Gyle Yearsley]

Is there any way to tell gcc that a processor can operate in byte
mode on all four bytes of a 32 bit register? If any of the bytes are used
then gcc would have to realize that the rest of the register was clobbered. 
I have not seen anywhere in the documentation or other ports where this is
done.

	32 Bit Register
---------------------------------------------------------
|  Byte 3  |  Byte 2 |  Byte 1|   Byte0     |
---------------------------------------------------------
The processor can use the 32 bit registers as a single 32 bit value or 4
byte wide values.

Thanks,

Gyle Yearsley
gyearsley@zilog.com