extrwi mnemonic conversion bounding error?

[Jason Sullivan]

Gas refuses to assemble the following statement, citing a bounding error...

extrwi  G1,G2,6,26

...The book converts this extended mnemonic to...

rlwinm G1,G2,32,26,31

..or...

rlwinm G1,G2,0,26,31

...because 32 is too high for the field.  This is why gas complains, of
course, but is it possible for gas to recognize this for what it is?  I
know this could be taken care of by a simple 'and' statement, but since
it's not immediately obvious what's wrong until you hand-translate the
extended mnemonic, gas should probalby either figure it out or throw a
better error.

Thanks!
--
Jason M. Sullivan
PowerPC Embbedded Processor Solutions
IBM Microelectronics
address@hidden (919.543.5650)