Re: targed.md: copy_to_mode_reg or force_reg?

[Georg-Johann Lay <avr at gjlay dot de>]

Joern Rennecke schrieb:

> If you actually need a new gcc backend and want it to be done well. you
> should instruct an experienced contractor to do it for you, or hire an
> in-house expert.

Allow me to reply offtopic by citing Abdulaziz Ghuloum:

"Compilers are perceived to be magical artifacts,
carefully crafted by the wizards, and unfathomable
by the mere mortals. Books on compilers are better
described as wizard-talk: written by and for a clique
of all-knowing practitioners. Real-life compilers are
too complex to serve as an educational tool. And the
gap between real-life compilers and the educational
toy compilers is too wide. The novice compiler writer
stands puzzled facing an impenetrable barrier, [...]"

> Your question reveals that you are not familiar with gcc, and further

Blame me for being a gcc novice. And being mortal.

Grepping and reading sources is one part in getting better understanding 
of gcc, browsing backends another, reading documentation or wiki (if 
available) is a third part, and a fourth could be asking in a 
forum/mailing list even if it's not on some fancy new gcc gadget but on 
a down-to-earth novice subject instead.

I am not dumb but I was not born as a gcc expert, either. It should be 
ok to ask beginners' question even if it seems trivial. Maybe there are 
some language barriers or misunderstandings because you are not a native 
speaker. Or you are just slow to catch on some topic or simply unsure if 
you understood everything right.

> suggests that you are trying to implement a new backend alone or in a team
> lacking a gcc expert.  This is likely to either fail or result in a
> backend of substandard quality which will never make it into the FSF
> repository.

I am not hired by a global company like google, ibm or redhat to push 
gcc. I did not study informatics and AVR is hobby, so I intend to 
volunteer for avr backend.

As far as I understand avr backend developers are quite rare and any 
help is appreciated, so I submitted some patches and FSF assignment is 
on the way...

> Thus, although your orginal question is valid in principle on this list,
> answering is not likely to really help you, nor are you likely to help
> the GCC community in the forseeable future if you are working on an
> over-ambitious project project.
> Thus, there is little incentive for anybody knowledgable reading this
> list to answer this question.

...the other way round, assisting a novice is appreciated as well.
Et oui, c'est pas pour les mérites.

In fact, I expected something like the polite version of "Dont't bother 
us gurus with greenhorn questions. Go and grep the fucking sources..."

> If the same question had been asked in a different context, e.g. a small
> patch to the x86 backend in order to support some new and exciting linux
> application, the odds of getting a timely response would have been higher.

Hope that will be true for small patches to the avr backend in order to 
support some mature and boring 8-bit µC applications, too ;-)

Regards,

Georg-Johann