Andy Green wrote: > When I build with SDCC, the IRAM is full - see .mem below. > > Since I'm using --model-large, what is it putting in IRAM? Is there a > way to find out what variables are being put in there? (and then to move > them out to xdata?!) > You are getting "spill locations". When SDCC doesn't have register space on hand for local variables, it will create spill locations in iram to hold them.
You can look for 'sloc' in your .lst, .rst and .map files for more information on where spill locations are allocated. The find the .lst and .rst files most helpful in tracking down these issues. With them you can see what it is that you are doing that causes spill locations to be allocated. If your subroutines are complex and work with lots of data, you can exhaust your registers pretty quickly. Manipulation of multiple generic pointers or long ints will often lead to spill locations. I have found that I can reduce spill locations by several tricks: * Make variables global instead of local. * Break complex math on longs into multiple single operations. Don't do "foo = (3 * bar) + baz;" Do this instead: foo = 3; foo *= bar; foo += baz; * Avoid generic pointers. * Break complex subroutines into smaller pieces. I hope this helps. --Mark Swayne ------------------------------------------------------------------------------ Open Source Business Conference (OSBC), March 24-25, 2009, San Francisco, CA -OSBC tackles the biggest issue in open source: Open Sourcing the Enterprise -Strategies to boost innovation and cut costs with open source participation -Receive a $600 discount off the registration fee with the source code: SFAD http://p.sf.net/sfu/XcvMzF8H _______________________________________________ Sdcc-user mailing list Sdcc-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sdcc-user
