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Altera_Forum
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14 years ago

Complete list of optimization flags for the Nios II compiler?

Hello all. Sorry if this has already been answered, I couldn't find it anywhere on the forums or online. We're migrating a large amount of source code written in C from an older processor to an...
Altera_Forum's avatar
Altera_Forum
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14 years ago

Marking the data 'volatile', or using the asm statement I mentioned earlier, will force the compiler to generate the actual memory cycles - possibly just to the cache.

Memory mapped IO registers should usually be marked 'volatile' (and be uncached), but if you are trying to verify the connections to cached or non-volatile 'memory' you need to force the compiler to flush any non-volatile data it has cached in registers, as well as flush and invalidate the data cache itself.