On the 65816, 16-bit data access instructions (e.g. LDA abs) are
expanded to 24 bits by merging in the Data Bank Register (B). The
value of the register is difficult to determine via static analysis,
so we need a way to annotate the disassembly with the correct value.
Without this, the mapping of address to file offset will sometimes
be incorrect.
This change adds the basic data structures and "fixup" function, a
functional but incomplete editor, and source for a new test case.
The test wasn't correctly excluding instructions, so it was possible
to create a situation where a two-byte data item had an instruction
starting in the second byte.
We also weren't checking the length of the instruction to ensure that
it was wider than the reloc data. This could get weird for an
immediate constant when the M/X flags are wrong. When in doubt, don't
overwrite.
JSR/JSL calls with inline data have the option of reporting that
they don't continue, which causes the code analyzer to treat them
as JMPs instead. There was a bug that was causing the no-continue
flag to be lost in certain circumstances.
The code now explicitly records the plugin's response in an Anattrib
flag. Test 2022-extension-scripts has been updated with a test case
that exercises this situation.
This began with a change to support "BRK <operand>" in cc65. The
assembler only supports this for 65816 projects, so we detect that
and enable it when available.
While fiddling with some test code an assertion fired. This
revealed a minor issue in the code analyzer: when overwriting inline
data with instructions, we weren't resetting the format descriptor.
The code that exercises it, which requires two-byte BRKs and an
inline BRK handler in an extension script, has been added to test
2022-extension-scripts.
The new regression test revealed a flaw in the 64tass code
generator's character encoding scanner that caused it to hang.
Fixed.
