Re: [avr-gcc-list] Re: C vs. assembly performance

[Bob Paddock]

> And the first complies with coding standards like gnu and gcc,
> and maybe even others like misra etc.

MISRA doesn't say a lot about style, that is how pretty
the code looks.  It is implicit that ugly looking code
is bad, and probably buggy.  If your code looks
like a IOCCC entry, your code would not be MISRA
complaint.
http://www.ioccc.org/

Per MISRA, in a nested if/else tree all brackets are required, and
there must be a final else{} as you showed.

As far as I can tell MISRA-2004 is silent on a preference
between switch(), nested if/else() and function pointers.
Personally I prefer tables of function pointers.  Makes
code looking like a threaded language like Forth at times.
In any case what can get hairy fast is conditionals containing
conditionals, which makes testing all execution paths problematic.

Note that technically no AVR-LibC based project complies
with MISRA due to rule #3.6 that says any library used,
including the GCC libraries, must be complaint with MISRA [IEC 61508
Part 3].  I tend to follow the MISRA Guidelines anyway as it shows an
attempt at Due Diligence.


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