Multifile support

[BacchusFLT]

I do believe we have talked about this via mail, and I can see aspects of how this would be difficult, but I would really like to see multifile support.

Today there is a hard link between a file and the disassembly, but my suggestion is that it would be possible to add several files to a project and that they would be seen as a combined virtual memory space. To simplify the topic a bit, I would be perfectly fine to have a requirement that the files couldn't be overlapping, to dodge the can of worms deriving from allowing overlap.

Think of the suggestion as an on-the-fly build of a larger file, only that it is built from several subfiles.

[fadden]

There are some separate but related things that fall into the "multi-file" bucket:

1. Automatic sharing of common symbols. For example, Stellar 7 has a graphics engine component and a couple of things (game, demo) that load into the same area at different times. It's possible to share symbols with explicit imports or shared .sym65 files, but it's not very convenient.
2. Constructing a "virtual image" from multiple binaries. You can do this now by concatenating the binaries together, but this will generate a single large source file, which will in turn assemble to a single large binary.
3. Outputting raw binaries as part of source generation. We had a discussion a while back about splitting out large data-only sections into a binary file, as there's no real value in having a large source file with nothing but data statements in it. (Issue "Collapse to external file" #144)
4. Generating multiple source files, for large binaries with overlays (Allow generation of multi-file sources #115).

[BacchusFLT]

Point 3 is another discussion and that's a separate topic. Still very relevant.

I was thinking of 2, and the "virtual" would be building that binary on the fly.

I see the point in 1 and 4, but I have yet to dive into projects where it's relevant. I guess I excluded them from the request when I was ok with this being restricted to a collection of files that aren't overlapping.

[BacchusFLT]

In my current project, the game loads a few files and then executes an intro, whereafter it loads a number of new files and start the actual game. If one file contains the code and the rest are sound and graphics, then it's just fine to reassemble the code file and you are good. But in my case several of the files contain code and in order to make the code understandable I had to manually join them into a large chunk and reassemble that one. The step of implementing the data from the reassembly of the single file to the reassembly of the big composite was a challenge, but doable. I would like to point at the wish to "virtually" build a view and have the reassemble be able to cross-reference. So your point 2, but within the scope of the program and not manually.

I fully understand the can of worms this opens (or I can at least see enough of it to feel discouraged by the complexity). What if I want to add and remove files from the virtual view? Do all assembler support generation of separate files from a common source file or would the reassembly generate one source file per individual file in the composite? If the latter, then how to make the working cross reference? Then there needs to be a "project file" for the multiple sources. How to handle overlaps between files?