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???
05/25/12 15:44
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 		 #187524 - you can do both
Responding to: ???'s previous message
I normally don't try to help the compiler.

I try to help other developers reading and understanding the code.

Today helping is not quite as important as it was when memory cost money, but I remember two things from when I saved $0.82 per each of 860.000 units by hand optimizing to one memroy size less.

while(1) and
for (;;;)
creted diferent code

if ( a && !b && !c)

created code different from
if (a)
{
if b break;
if c break;

neither of the above made the code less readable.

I would agree that obfusciating code to help the compiler is a VERY bad idea.

I really do not know which of my "routine compiler helpers" still make a difference (and have forgotten which are "compiler helpers and which are "style") but since none are obfusciating the code I have no concern.

Erik

List of 33 messages in thread
TopicAuthorDate
Where can one learn Intermediate C techniques for 8051            01/01/70 00:00      
   on the right track            01/01/70 00:00      
      one more thing            01/01/70 00:00      
         Not uncommon bid bad coding standards to comply with            01/01/70 00:00      
         Not afraid of globals, but...            01/01/70 00:00      
   More keil optimizer interesting tidbits            01/01/70 00:00      
      optimization            01/01/70 00:00      
      nothing gained, nothing lost            01/01/70 00:00      
         I don't            01/01/70 00:00      
            you can do both            01/01/70 00:00      
               That is not helping the compiler            01/01/70 00:00      
                  exact same            01/01/70 00:00      
                     Technically, they are not the same            01/01/70 00:00      
                        Hmmm...            01/01/70 00:00      
                        C don't do full evaluation of logical expressions            01/01/70 00:00      
                           In discrete mathematics proving one is not a proof            01/01/70 00:00      
                              Lazy evaluation demanded            01/01/70 00:00      
                                 I have learned something new because of this            01/01/70 00:00      
                                    me too            01/01/70 00:00      
                                       Very Important            01/01/70 00:00      
                              Breaks.            01/01/70 00:00      
                                 Compile the code            01/01/70 00:00      
                                    To be more exact            01/01/70 00:00      
                                       Stop It!!            01/01/70 00:00      
                                          That is exactly what I intended            01/01/70 00:00      
                                             Switch Break.            01/01/70 00:00      
               obfusciating code to help the compiler is a VERY bad idea            01/01/70 00:00      
                  the source of this            01/01/70 00:00      
   Where can one learn Intermediate C techniques for 8051            01/01/70 00:00      
   Getting the least out of your compiler            01/01/70 00:00      
      Maybe IAR should follow their own advice?            01/01/70 00:00      
         provided the case ...            01/01/70 00:00      
            Compilers not knowing the target chip.            01/01/70 00:00      

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