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Certain pseudo opcodes are permitted. They are for branch
instructions. They expand to the shortest branch instruction that
reaches the target. Generally these mnemonics are made by
substituting j
for b
at the start of a DEC mnemonic.
This feature is included both for compatibility and to help
compilers. If you do not need this feature, avoid these
opcodes. Here are the mnemonics, and the code they can expand into.
jbsb
Jsb
is already an instruction mnemonic, so we chose jbsb
.
jbr
jr
jCOND
neq
, nequ
, eql
, eqlu
, gtr
,
geq
, lss
, gtru
, lequ
, vc
, vs
,
gequ
, cc
, lssu
, cs
.
COND may also be one of the bit tests
bs
, bc
, bss
, bcs
, bsc
, bcc
,
bssi
, bcci
, lbs
, lbc
.
NOTCOND is the opposite condition to COND.
jacbX
b d f g h l w
.
OPCODE ..., foo ; brb bar ; foo: jmp ... ; bar:
jaobYYY
lss leq
.
jsobZZZ
geq gtr
.
OPCODE ..., foo ; brb bar ; foo: brw destination ; bar:
OPCODE ..., foo ; brb bar ; foo: jmp destination ; bar:
aobleq
aoblss
sobgeq
sobgtr
OPCODE ..., foo ; brb bar ; foo: brw destination ; bar:
OPCODE ..., foo ; brb bar ; foo: jmp destination ; bar: