[fpc-devel] generated assembler code
lazarus at mfriebe.de
Tue May 19 18:18:51 CEST 2015
On 19/05/2015 14:23, Jonas Maebe wrote:
> Martin Frb wrote on Tue, 19 May 2015:
>> 005EACF0 833A00 cmp dword ptr [edx],$00
>> 005EACF3 0F95C0 setnz al
>> 005EACF6 84C0 test al,al
>> 005EACF8 7509 jnz +$09
>> Is that something that should be optimized away?
> I'm sure you can find 100's of examples like that when using inline.
> So yes, it's obviously a missed optimisation, but an x86 peephole
> optimisation to remove those two instructions is "dweilen met de kraan
> open" (mopping up water while leaving the tap running), and (as far as
> I'm concerned) a waste of time since exactly the same happens on all
> architectures as well (except for possibly those without flags).
I knew why I ask for optimization in general, and not at any specific
I was more interested if (with any disregard to priority or importance)
1) it is a known issue
2) regarded as issue at all
Appears to be.
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