<s>
In	O
computer	O
engineering	O
,	O
a	O
register	B-Architecture
–	I-Architecture
memory	I-Architecture
architecture	I-Architecture
is	O
an	O
instruction	B-General_Concept
set	I-General_Concept
architecture	I-General_Concept
that	O
allows	O
operations	O
to	O
be	O
performed	O
on	O
(	O
or	O
from	O
)	O
memory	B-General_Concept
,	O
as	O
well	O
as	O
registers	B-General_Concept
.	O
</s>
<s>
If	O
the	O
architecture	O
allows	O
all	O
operands	O
to	O
be	O
in	O
memory	B-General_Concept
or	O
in	O
registers	B-General_Concept
,	O
or	O
in	O
combinations	O
,	O
it	O
is	O
called	O
a	O
"	O
register	O
plus	O
memory	B-General_Concept
"	O
architecture	O
.	O
</s>
<s>
In	O
a	O
register	O
–	O
memory	B-General_Concept
approach	O
one	O
of	O
the	O
operands	O
for	O
operations	O
such	O
as	O
the	O
ADD	O
operation	O
may	O
be	O
in	O
memory	B-General_Concept
,	O
while	O
the	O
other	O
is	O
in	O
a	O
register	O
.	O
</s>
<s>
This	O
differs	O
from	O
a	O
load	B-Architecture
–	I-Architecture
store	I-Architecture
architecture	I-Architecture
(	O
used	O
by	O
RISC	B-Architecture
designs	O
such	O
as	O
MIPS	B-Device
)	O
in	O
which	O
both	O
operands	O
for	O
an	O
ADD	O
operation	O
must	O
be	O
in	O
registers	B-General_Concept
before	O
the	O
ADD	O
.	O
</s>
<s>
An	O
example	O
of	O
register-memory	B-Architecture
architecture	I-Architecture
is	O
Intel	B-Operating_System
x86	I-Operating_System
.	O
</s>
<s>
Examples	O
of	O
register	O
plus	O
memory	B-General_Concept
architecture	O
are	O
:	O
</s>
<s>
IBM	B-Application
System/360	I-Application
and	O
its	O
successors	O
,	O
which	O
support	O
memory-to-memory	O
fixed-point	O
decimal	O
arithmetic	O
operations	O
,	O
but	O
not	O
binary	O
integer	O
or	O
floating-point	B-Algorithm
arithmetic	I-Algorithm
operations	O
;	O
</s>
<s>
VAX	B-Device
,	O
which	O
supports	O
memory	B-General_Concept
or	O
register	O
source	O
and	O
destination	O
operands	O
for	O
binary	O
integer	O
and	O
floating-point	B-Algorithm
arithmetic	I-Algorithm
;	O
</s>
<s>
the	O
Motorola	B-Device
68000	I-Device
series	I-Device
,	O
which	O
supports	O
integer	O
arithmetic	O
with	O
a	O
memory	B-General_Concept
source	O
or	O
destination	O
,	O
but	O
not	O
with	O
a	O
memory	B-General_Concept
source	O
and	O
destination	O
.	O
</s>
