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Re: [DOC Patch] Explicit Register Variables



On 6/30/2014 6:30 PM, Mike Stump wrote:
On Jun 30, 2014, at 4:10 PM, David Wohlferd <dw@LimeGreenSocks.com> wrote:
- Vague descriptions of things that "are reported" to work on certain
platforms are not useful ("On the SPARC, there are reports that").
I'd disagree.  But what's more important here is the registers that are available are a function of the ABI and for someone to attempt to use this feature, they're going to have to be intimately aware of the ABI of their target.
If we could say "On the SPARC, these registers can be used for" I'd be tempted to leave it as an example.  But saying "Well, someone once said they thought it might work this way on this one specific platform" is not helpful for either SPARC or non-SPARC users.
So, we can do s/there are reports that//; s/should be suitable, as should/are suitable, as are/ and remove the wishy washy language.  If someone later wants to correct the definitive statement in some way, they are welcome to it.

We could.

While an example can be illustrative, the potential value here is offset by the fact that it may not actually be true. Given that, I think I'd just as soon do without an example.

My proposed patch says "When selecting a register, choose one that is normally saved and restored by function calls on your machine. This ensures library routines which are unaware of this reservation will restore it before returning." This platform-neutral statement seems to cover what needs to be said here.

dw


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