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Powerpc IRQ handling breaks strict EABI compliance



Valette Eric <eric.valette at free.fr> writes:
> Sergei Organov wrote:
> 
> > By default, variables/constants not larger than 8 bytes are put into small
> > data sections, but this is configurable. Actual gain depends on the style
> > application is written in though.
> 
> How much data can you handle this way? 64K?

64K for read/write data + 64K for read-only data. 

> Do you have any performance and code size figures to be more concrete? (e.g
> by compiling your application with and without the compiler eabi flags and
> running the benchmarks...).

Unfortunately not. The only thing I know for sure is that my application
doesn't fit into a few of my boards without EABI and does fit with it. Code
speed improvement is a guess I've looking at the assembly code generated by
gcc in both cases.

Just tried to re-build one of my applications without EABI (RTEMS is still
compiled with EABI). The difference in code size is:

-meabi -msdata=eabi:    362032
-mno-eabi -msdata=none: 378720

If newlib/glib is also compiled without EABI, the code size is:
                        380320

So for my application it's about 5% difference.

-- 
Sergei.