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Re: [RFA:] Fix for lsb0? in -gen-extract-word, take 2.


Hi -

On Mon, Jun 24, 2002 at 09:50:00PM -0400, Hans-Peter Nilsson wrote:
> Here's a less intrusive fix since I couldn't wrap my head around
> what adjustment there should be for the "<<" expression.  I
> can't figure out whether it actually has lsb0?-issues at all, so
> I'll not touch it.  Again, only tested on the CRIS (wip) target.
> [...]

Let me voice one note of caution regarding this area.  cgen is
not fully developed with respect to variable-length instruction
sets, and some other odd cgen-isa parametrizations.  This has
been making it necessary to use lsb0=#f for several cpu ports.
I'm worried that modification of something as low-level as
gen-extract-* can easily break these unusual ports. 
Unfortunately, only "medium-weird" ports are on the sourceware
cgen repository, so it's possible that a change will break only
a port you don't (yet) have access to.

Anyway, please keep in mind that you're treading on fragile
territory.


- FChE


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