VTBL and VTBX
Vector Table Lookup, Vector Table Extension.
Syntax
V
{op
}.8
cond
, Dd
,
list
Dm
where:
op
must be either
TBL
orTBX
.cond
is an optional condition code.
Dd
specifies the destination vector.
list
Specifies the vectors containing the table. It must be one of:
{
.Dn
}{
.Dn,D(n+1)
}{
.Dn,D(n+1),D(n+2)
}{
.Dn,D(n+1),D(n+2),D(n+3)
}{
.Qn,Q(n+1)
}
All the registers in
must be in the rangelist
D0
-D31
orQ0
-Q15
and must not wrap around the end of the register bank. For example {D31
,D0
,D1
} is not permitted. If
containslist
Q
registers, they disassemble to the equivalentD
registers.Dm
specifies the index vector.
Operation
VTBL
uses byte indexes in a control vector to look up byte values in a
table and generate a new vector. Indexes out of range return zero.
VTBX
works in the same way, except that indexes out of range leave the
destination element unchanged.