Note that address region isolation doesn't prevent explicit label
references from working (add update the test to prove it).
Added a note about pre-label xrefs.
If an address resolves to a user label in an isolated region, we
don't want to use it. However, we still want to try to match it
to a project/platform symbol.
For example, suppose the isolated code wants to reference address
$1C00, which is a memory-mapped I/O location in one area, but a
regular bunch of code in the other. We don't want it to map to
the regular code, but we do want it to resolve to our table of
platform I/O addresses.
We now handle this correctly. The regression test has been updated
to check this. The current implementation does a linear scan through
the symbol table, but I'm hoping this is not a common situation.
The reference manual has been updated to describe the new feature.
Added an address-to-offset test in the GeneratePlatformSymbolRefs()
method, which sets the operand symbols for anything that lands outside
the scope of the file. Because the region isolation code prevented
symbols from being associated with the operands in the initial code
scan, those operands were being examined here. Without the additional
test, the inappropriate label associations were getting a second chance.
Added "[!in]" and "[!out]" to the comment field of .addrs lines. This
is only for the on-screen display and text exports, not asm gen.
Bumped the project file CONTENT_VERSION.
Added a regression test (20290-region-isolation).
The test turned up an existing problem: pre-labels are emitted by the
asm generators on their own line, but the code that puts excessively
long labels on a separate line wasn't taking that into account. This
has been fixed. No changes to existing regression tests, which didn't
happen to use long labels.
