Re: BUG: non-fixed-length ISAs are unsupported for now
"Frank Ch. Eigler via Cgen" <[email protected]> Wed, 12 Aug 2020 15:57:01 -0400
| Newsgroups | gmane.comp.tools.cgen.devel |
|---|---|
| Message-ID | <[email protected]> |
Hi - > Ok. How to handle variable size instructions then? For example: > NOP - 0x00 > NEG - 0xed 0x44 > RLC B - 0xcb 0x00 > LD HL, 0x1234 - 0x21 0x34 0x12 > LD IY, 0x1234 - 0xfd 0x21 0x34 0x12 > LD DE, (0x1234) - 0xed 0x5b 0x34 0x12 > RR (IX+9) - 0xdd 0xcb 0x09 0x1e (here 0x09 is 8-bit signed immediate) Simply, make no change other than setting the base-insn large enough to contain all the opcode fields. Amongst all these cases, that seems to be 16 or perhaps 24 bits. I suggest trying 32. - FChE