> -----Original Message----- > From: avr-gcc-list-bounces+eric.weddington=atmel....@nongnu.org > [mailto:avr-gcc-list-bounces+eric.weddington=atmel....@nongnu.org] On > Behalf Of Erik Walthinsen > Sent: Wednesday, October 10, 2012 3:13 PM > To: avr-gcc-list > Subject: Re: [avr-gcc-list] >4.5.1 better than this at register-structure > (xmega) access? > > On 10/10/2012 01:43 PM, Georg-Johann Lay wrote: > > Such a bug has never been reported to the GCC bug tracker. > Well then, I guess I need to file one. I just have no idea how to > actually fix it, and no time to do so at this point ;-( > > > If nobody found it important enough to file a problem report for over 3 > > years (4.5 was released early 2009) I'd guess this is simply not an > > important issue? > It's not a bug per se but a missing optimization, so it's entirely > possible nobody's cared enough to check. I'm a) doing some extremely > time-critical ISR routines, and b) trying to actually make use of the > struct convenience. > > > There is PR50448 which is similar but different and fixed for 4.7.0. > Yeah, doesn't look like the same issue at all. > > > Xmega is supported in avr-gcc since 4.7.0 (PR52261) so you obviously use > > some private port with its own, private bug tracker.
> No, I'm using a version that matched the latest toolchain source I could > get from Atmel at the time (6-12mo ago?) and took their patches > including Xmega, which didn't include any more than the 64a1u, 128a1u, > and 256a3bu. I had to go through *all* the toolchain to add in the rest > of the parts that are available from Digikey. Johann is being pedantic. Atmel has their own set of patches, i.e. it *is* a private port, because those patches aren't fully submitted upstream yet. > > So, I guess I'll ask again: where do I actually get TODAY's toolchain? > I keep reading about how Atmel takes forever to release the patches to > the toolchain they ship, yet they now seem to be the "only" official > toolchain, and nobody else appears to be actually maintaining patches > separately. Unless the GCC core is actually being kept up now and > nobody bothered to mention it, but I just downloaded 4.7.2 and found the > exact same set of parts missing. I'm working on getting Atmel's patches upstream. But specifically to your problem: I've had a latent concern about the xmega register definitions via structure layout. My concern is that the compiler would do exactly as you describe and always try to do an address/offset type of access to registers. But as you said: Does it do that with recent versions? I'm afraid that no one yet knows. Eric Weddington _______________________________________________ AVR-GCC-list mailing list AVR-GCC-list@nongnu.org https://lists.nongnu.org/mailman/listinfo/avr-gcc-list
