Re: GCC floating point usage

[Mark Mitchell <mark@codesourcery.com>]

--On Wednesday, October 16, 2002 10:53:33 PM +0200 Michael Matz 
<matz@suse.de> wrote:

> Hi,
>
> On Wed, 16 Oct 2002, Mark Mitchell wrote:
>
>> > (a) Does this affect codegen when the new feature is not enabled?
>> >     Zack's patch does, and it shouldn't.
>>
>> I certainly agree that people not using the flag should see no change.
>>
>> Why does Zack's patch do that, given his caveat that the sense of the
>> flag would be reversed so that the flag is off by default?
>
> Because it adds an additional insn pattern, with equal predicates as
> the following one, but with different constraints.  This means, that in
> the case this pattern is activated (which it is by default, given Zacks
> changed default proposal) it will be preferred, which means, because it
> only lists float regs in constraints, that float regs will be preferred.

That sounds like a problem that needs to be fixed.

We're still hung up on a more basic problem, though; the RS6000
maintainers haven't yet made an up-or-down decision on the idea of
the flag...

-- 
Mark Mitchell                mark@codesourcery.com
CodeSourcery, LLC            http://www.codesourcery.com