Code generated by one of the C compilers sets up the stack frame and
then maps the direct page on top of it. If the value at the top of
the stack is 16 bits, it will be referenced via address $ff. The
local variable editor was regarding this as illegal, because lvars are
currently only defined for direct page data, and the value doesn't
entirely fit there (unless you're doing an indirect JMP on an NMOS
6502, in which case it wraps around to $00... but let's ignore that).
The actual max width of a local variable is 257 because of the
possibility of a 16-bit access at $ff.
Older versions of SourceGen don't seem to have an issue when they
encounter this situation, as worrying about (start+width) is really
just an editor affectation. The access itself is still a direct-page
operation. You won't be able to edit the entry without reducing the
length, but otherwise everything works. I don't think there's a need
to bump the file version.
If you double-click a project symbol declaration, the symbol editor
opens. I found that I was double-clicking on the comment field and
typing with the expectation that the comment would be updated, but
it was actually setting the initial focus to the label field.
With this change the symbol editor will focus the label, value, or
comment field based on which column was double-clicked.
The behavior for Actions > Edit Project Symbol and other paths to the
symbol editor are unchanged.
Also, disabled a wayward assert.
Project symbol address values are now limited to positive 24-bit
integers, just as they are for platform symbols. Constants may
still be 32-bit values.
Memory-mapped I/O locations can have different behavior when read
vs. written. This is part 1 of a change to allow two different
symbols to represent the same address, based on I/O direction.
This also adds a set of address masks for systems like the Atari
2600 that map hardware addresses to multiple locations.
This change updates the data structures, .sym65 file reader,
project serialization, and DefSymbol editor.
The ability to give explicit widths to local variables worked out
pretty well, so we're going to try adding the same thing to project
and platform symbols.
The first step is to allow widths to be specified in platform files,
and set with the project symbol editor. The DefSymbol editor is
also used for local variables, so a bit of dancing is required.
For platform/project symbols the width is optional, and is totally
ignored for constants. (For variables, constants are used for the
StackRel args, so the width is meaningful and required.)
We also now show the symbol's type (address or constant) and width
in the listing. This gets really distracting when overused, so we
only show it when the width is explicitly set. The default width
is 1, which most things will be, so users can make an aesthetic
choice there. (The place where widths make very little sense is when
the symbol represents a code entry point, rather than a data item.)
The maximum width of a local variable is now 256, but it's not
allowed to overlap with other variables or run of the end of the
direct page. The maximum width of a platform/project symbol is
65536, with bank-wrap behavior TBD.
The local variable table editor now refers to stack-relative
constants as such, rather than simply "constant", to make it clear
that it's not just defining an 8-bit constant.
Widths have been added to a handful of Apple II platform defs.
Split "edit local variable table" into "create" and "edit prior".
The motivation is to allow the user to make changes to the most
recently defined table without having to go search for it. Having
table creation be an explicit action, rather than something that
just happens if you edit a table that isn't there, feels reasonable.
Show table offset in LV table edit dialog, so if you really want
to go find it there's a (clumsy) way to do so.
Increased the maximum width of a variable from 4 to 8. (This is
entirely arbitrary.)
Typing a long comment in the project symbol editor caused the
window to expand, which wasn't intended. Use the mono font in
the comment editor. Set the focus to the OK button after creating
or editing a project property. Show constant vs. address in the
info panel when an EQU directive is selected.
It's possible to define multiple project symbols with the same
address. The way to resolve the ambiguity is to explicitly
reference the desired symbol from the operand. This was the
default behavior of the "create project symbol" shortcut in the
previous version.
It's rarely necessary, and it can get ugly if you rename a project
symbol, because we don't refactor operands in that case.
Implemented local variable editing. Operands that have a local
variable reference, or are eligible to have one, can now be edited
directly from the instruction operand edit dialog.
Also, updated the code list double-click handler so that, if you
double-click on the opcode of an instruction that uses a local
variable reference, the selection and view will jump to the place
where that variable was defined.
Also, tweaked the way the References window refers to references
to an address that didn't use a symbol at that address. Updated
the explanation in the manual, which was a bit confusing.
Also, fixed some odds and ends in the manual.
Also, fixed a nasty infinite recursion bug (issue #47).
We now generate FormatDescriptors with WeakSymbolRefs for direct
page references that match variable table entries.
LocalVariableTable got a rewrite. We need to be unique in both
name and address, but for the address we have to take the width into
account as well. We also want to sort the display by address
rather than name. (Some people might want it sorted by name, but
we can worry about that some other time.)
Updated the DefSymbol editor to require value uniqueness. Note
addresses and constants exist in separate namespaces.
The various symbols are added to the SymbolTable so that uniqueness
checks work correctly. This also allows the operand generation to
appear to work, but it doesn't yet handle redefinition of symbols.
Multi-line item, with one .eq line per variable definition. Add
one header line if "clear previous" is set.
Also, limit variable values to 0-255 in the editor. This is
somewhat arbitrary, but I think a focus on DP is useful.
The table editor is now editing the table, and the DefSymbol editor
now asks for the Width data when editing a local var.
This also moves EditDefSymbol closer to proper WPF style, with
bound properties for the input fields.
No changes yet to serialization or analysis.
