Actually I haven't really planned anything related to this. I don't even know yet what these actually mean (well I know it theoretically, but not in the compiler-linker context).
The data would definately be in the lower 64K, because of the 16-bit pointers. (My guess was that nothing had to be changed in this, because they are already located there, anyway). What to do with the function pointers? Good question. If I want to use full-size pointers, I'll probably have to change a lot of things too. What does using vectors mean? Having two pointers for one address? I think all of this is far too complicated for someone who hasn't ever used/worked with these stuff. I'll check the avr-gcc mailing list, thanks for the tip. Best regards, Oszkar David Brown <[email protected]> Sent by: [email protected] 04/13/2007 01:18 PM Please respond to "GCC for MSP430 - http://mspgcc.sf.net"; <[email protected]> To "GCC for MSP430 - http://mspgcc.sf.net"; <[email protected]> cc Subject Re: [Mspgcc-users] mspcgg to support MSP430X Before you go any further, you should probably have a look through the avr-gcc mailing list archives, and possibly look at their implementations. They have recently gone through a similar process for the newer AVR cores with larger memories. If you are only using 16-bit data pointers (and I agree that makes sense, at least for most applications), then it's important that you put the rodata section in the low part of the flash in your linker file. What are you planning to do about function pointers? There are a few ways to deal with this. You can either have full-size pointers, or put vectors in the low memory so that function pointer calls are indirect. It is somewhat of a challenge to get this working well, so that you use vectors when needed, but don't waste the time or space when they are not needed. mvh., David Oszkar Ambrus wrote: > > Ok, thank you very much. > Then probably I'll start working on that, after adding 'calla' to the > compiler. > > I'm not planning to add 20-bit data instructions to the compiler, > because that would be very hard, and mostly useless. > What I intend to do is add only tha calla and reta to support 1Mb of > code size. > > What I ran into is that the msp430.c nor the msp430.md do not use an > emit_call instruction, like other architectures do. > That complicates things a lot. I do not know where to make it use a > 20-bit call, if I implement that in binutils. > So I'd like to see first, that it does generate the correct assembler > code, and than add the binutils functionality. > > Your help would be really appreciated, > Regards, > Oszkar > > > > > > *Grant Edwards <[email protected]>* > Sent by: [email protected] > > 04/12/2007 05:41 PM > Please respond to > "GCC for MSP430 - http://mspgcc.sf.net"; <[email protected]> > > > > To > [email protected] > cc > > Subject > Re: [Mspgcc-users] mspcgg to support MSP430X > > > > > > > > > On 2007-04-12, Oszkar Ambrus <[email protected]> wrote: > > > Thank you for your answers. So actually there isn't any > > instruction generation for the MSP430X. > > > > Which version should I work on, if I want to add support for > > that? The CVS mspgcc contains mspgcc for gcc-4.1.1 as well. > > > > And how should I start working? I added the 'reta' instruction > > into the msp430.c file, but can't seem to find where to add > > 'calla'. Are there many other things that need to be changed > > (like binutils)? > > I presume that new 20-bit relocation types need to be defined > and added to binutils? > > > Can I get any help on this anywhere? Should I post these > > questions somewhere else? :) > ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Mspgcc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mspgcc-users
