What is the quickest way to determine the total size of code/data to know how much on chip memory has been allocated to run your code ?
the quickest way is to generate a Linker Map File via 'Project Options: Link', then add up the totals from the 'used' column. There is no automated process to get the total data/code size.
In the map file I assume the number of used/unused words is 32 bit words not bytes ? What does the unused words signify ? Is that the remaining space left in the segment ?
Also in the individual section tables is the Size of each of the functions given in bytes or 32 bit words ??
Also does the compiler support overlays for non time critical portions of the code ?
yes, the sizes are given in words, not 8-bit-bytes, as are the sizes of the objects within each section summary. You can cross reference the map file with the LDF file from your project for section sizes, etc. The unused space is the 'free' space in that memory section, where no objects have been allocated.
There are a couple of application notes on implementing overlays on SHARC processors, available from the link below, EE284 and EE230 in particular.
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