JP (HL) / (IX) / (IY) lifted as a memory-indirect jump

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
76/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Quiet
Tech stack
python
Domain
reverse-engineering

Research direction

Start in Z80IL.py at goto_or_jump() and trace how the register-deref target is passed to operand_to_il(). Check the JP (HL), JP (IX), and JP (IY) cases, then verify that the lifted output treats each register as the jump target rather than loading from memory. Confirm the standard Z80 jump-table dispatch behavior.

Written by the indexing model from the issue text.

Description

For a register-deref target, goto_or_jump() in Z80IL.py runs the operand through operand_to_il() without peel_load=True, so it emits a load:

e9   JP (HL)   ->   jump([HL].w)      # should be jump(HL)

JP (HL) jumps to the address in HL, it does not dereference it. This breaks the standard Z80 jump-table dispatch idiom.

Dominant language
Python
Stars
12
Forks
5
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