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4d13d57491
When '@' is used as argument of any instruction (LD, JR, JP, etc), the
address it refers to is the address of the first byte of the
instruction. When '@' is used with DB/DW/DL, it refers to the same
address it is being placed at. This means that instructions need an
offset of 1 byte and others need an offset of 0 bytes.
The assembler doesn't evaluate anything related to '@' because it would
only work in sections with a fixed base address. It is left to the
linker. This means that the offset needs to be added to the RPN
expression of the patch that is saved in the linker. It isn't enough by
adding an offset to the final expresion. The following value wouldn't be
calculated correctly (even if it doesn't make sense):
JP @ * @
The correct patch is `(@ - 1) * (@ - 1)`, not `(@ * @) - 1`.
This patch introduces an offset on 1 byte by default in every line, and
sets it to 0 only if a DB/DW/DL is detected.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>