[fpc-devel] CMem allocator memory alignment experiment

[Mark Morgan Lloyd]

Sergei Gorelkin wrote:
> 19.11.2014 15:16, Marco van de Voort ?????:> In our previous episode, 
> Mark Morgan Lloyd said:>>>> introduces a very significant performance 
> overhead;>>>>>> Linux also does this.>>>> On some but by no means all 
> platforms. I'm specifically trying to>> highlight the fact that on 
> SPARC, Solaris can fix alignment issues (at a>> price) but Linux doesn't 
> try to. I don't know to what extent there are>> comparable issues on 
> other platforms (in particular x86_64) for which>> both Solaris and 
> Linux are implemented.>> On PPC (603), Linux did, but netbsd didn't :-)  
> Though that is 1.9.0 times> experience and thus slightly dated.

> On mips-linux, I observe no crashes when doing unaligned access with 
> integer instructions, but it still crashes upon unaligned access using 
> floating-point instructions.
> Sergei

Useful to know. I've never tried this, but presumably the signal can be 
trapped?

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

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