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Re: Can I force a word read-modify-write instread of a byte write?


Ian Lance Taylor wrote:
Oh, I see, you want the compiler to figure stuff out for you.

Yes please :-)


Unfortunately, that won't work.  You need to write the 32-bit
read/modify/write instructions yourself.

Yes, that was '(b)' in my question I think. I'm just looking for a lazy way to avoid work.


There is nothing in gcc which will force it to use 32-bit memory
accesses if you don't explicitly write 32-bit memory accesses.

My recollection is that if the processor doesn't have instructions for a particular width, gcc will synthesize the access. I was just hoping that there was some 'magic hack' that could activate that functionality.



Cheers,


Phil.





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