Re: [avr-gcc-list] RFC: Speeding up small ISRs: PR20296

[Erik Christiansen]

On 14.07.17 19:18, Georg-Johann Lay wrote:
> The according avr-gcc feature is also upstream now.  It adds a new option
> -m[no-]gas-isr-prologues and a new function attribute to disable __gcc_isr
> generation for individual ISRs:
> 
> http://gcc.gnu.org/onlinedocs/gcc/AVR-Function-Attributes.html
> 
> If you want to play around with it, you need Binutils that implement PR20296
> (e.g. Binutils GIT master or upcoming 2.29) and avr-gcc that implements
> PR81268 (GCC SVN trunk r250093 or newer).
> 
> The feature is enabled per default for all optimization levels except for
> -O0 and -Og.

Thank you, Johann, for all the work I've seen coming in on binutils and
gcc-patches. The stuff I have in hand still uses assembler ISRs, easily
linkable with C code. After 30 years of it, I still find it easier to
write an ISR in assembler than C - and I know where each part microsecond
is expended, so latency is known in advance.

It is very encouraging, though, to see continuing development of the AVR
toolchain.

Erik