This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH V3, #1 of 10], Add basic pc-relative support


On Fri, Sep 06, 2019 at 07:50:51AM -0500, Segher Boessenkool wrote:
> On Thu, Sep 05, 2019 at 08:18:02PM -0400, Michael Meissner wrote:
> > On Thu, Aug 29, 2019 at 04:32:07PM -0500, Segher Boessenkool wrote:
> > > This is not just for reload anymore, so please don't name it that.  Renaming
> > > things isn't hard, this isn't a public API or anything :-)
> > 
> > This hasn't just be for reload for several years now.
> 
> Yes, and since you are extending it a lot now, it is high time it is fixed.
> 
> > Do you have a name you prefer?
> 
> As I said, I don't think all these things should be lumped together at
> all, and also you shouldn't precompute everything (as fixed values
> always, after that precompute) into arrays anyway.  Instead, use
> functions for all accessors, which can have simple and clear logic what
> they return when.
> 
> If it is hard to find good names for your interfaces, most likely your
> interfaces aren't structured very well.

Here is where I disagree.  I tend to think pre-computing the stuff saves time.
When you are using it with pre-computed masks and such, it takes 5-10
instructions to make the decision, while if you have to re-do the tests (for
example, checking size, checking whether it is int/fp/vector, it can involve
many more tests than a simple load/mask type test).

But if it is the only way to get things in, I can look at not using the address
masks any further, and instead have discreet tests.

-- 
Michael Meissner, IBM
IBM, M/S 2506R, 550 King Street, Littleton, MA 01460-6245, USA
email: meissner@linux.ibm.com, phone: +1 (978) 899-4797


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]