Re: [wwwdocs] mention AVR additions

[Gerald Pfeifer <gerald at pfeifer dot com>]

Hi Johann,

On Wed, 13 Dec 2017, Georg-Johann Lay wrote:
> This adds AVR improvements to v8 Release Notes.

that's quite impressive a set of improvements!

Index: changes.html
===================================================================
>     The new devices are filed under 
>     <a href="https://gcc.gnu.org/onlinedocs/gcc/AVR-Options.html";><code>-mmcu=avrxmega3</code></a>.

I'm not sure whether "filed under" is the best choice of wording (and
when I say that, I really am not).  So perhaps use "listed" under or
similar?

> 	features like <code>PROGMEM</code> and <code>__flash</code>
> 	are no more needed (as opposed to other AVR families for which

"are not needed any more"

> 	that the compiler is used with Binutils&nbsp;2.29 or newer so that
> 	read-only data will be located in flash memory, see feature
> 	<a href="https://sourceware.org/PR21472";>PR21472</a>.</li>

How about using "read-only data will be located in flash memory" the
text for that link, and omit the "see feature PR..." part?  That'll
make it easier to read.

>       <li>A new command line option <code>-mshort-calls</code> is supported.

"command-line"

> 	This option is used internally for multilib selection of the
> 	<code>avrxmega3</code> variants.
> 	It is <em>not an optimization option</em>, and you don't need to set
> 	it by hand.</li>

"do not" to emphasize this more strongly.

>     The compiler now implements feature <a href="http://gcc.gnu.org/PR20296";>PR20296</a>
>     and will generate more efficient interrupt service routine (ISR)
>     prologues and epilogues.

Here I suggest "The compiler now generates..." (and perhaps make this a
link to the PR, but use https here).

>       <li>A new command line option <code>-mno-gas-isr-prologues</code>

"command-line"

> 	has been added.  It disables the generation of the

How about "A new command line option <code>-mno-gas-isr-prologues</code>
disable the generation..."?  Shorter and easier to read.

> 	Any non-naked ISR will save and restore SREG, tmp_reg and zero_reg,

<code>...</code> around SREG, tmp_reg and zero_reg.

>       <li>The feature is turned on per default for all optimization levels
> 	except for <code>-O0</code> and <code>-Og</code>. It can still be
>       enabled by means of option <code>-mgas-isr-prologues</code>.</li>

"It is explicitly enabled by..."

>       <li>Support has been added for a new
> 	<a href="https://gcc.gnu.org/onlinedocs/gcc/AVR-Function-Attributes.html";>AVR function attribute</a>
> 	<code>no_gccisr</code>.

Is there something missing after "a new"?  "A new" what?


Please go ahead and commit (taking the above into account) and just
share the final patch here in response.

Thank you for taking the time to document all this!

Gerald