<s>
In	O
computer	O
engineering	O
,	O
a	O
load	B-Architecture
–	I-Architecture
store	I-Architecture
architecture	I-Architecture
(	O
or	O
a	O
register-register	O
architecture	O
)	O
is	O
an	O
instruction	B-General_Concept
set	I-General_Concept
architecture	I-General_Concept
that	O
divides	O
instructions	O
into	O
two	O
categories	O
:	O
memory	B-General_Concept
access	O
(	O
load	B-Architecture
and	I-Architecture
store	I-Architecture
between	O
memory	B-General_Concept
and	O
registers	B-General_Concept
)	O
and	O
ALU	B-General_Concept
operations	O
(	O
which	O
only	O
occur	O
between	O
registers	B-General_Concept
)	O
.	O
</s>
<s>
Some	O
RISC	B-Architecture
architectures	I-Architecture
such	O
as	O
PowerPC	B-Architecture
,	O
SPARC	B-Architecture
,	O
RISC-V	B-Device
,	O
ARM	B-Architecture
,	O
and	O
MIPS	B-Device
are	O
load	B-Architecture
–	I-Architecture
store	I-Architecture
architectures	I-Architecture
.	O
</s>
<s>
For	O
instance	O
,	O
in	O
a	O
load	O
–	O
store	O
approach	O
both	O
operands	O
and	O
destination	O
for	O
an	O
ADD	O
operation	O
must	O
be	O
in	O
registers	B-General_Concept
.	O
</s>
<s>
This	O
differs	O
from	O
a	O
register-memory	B-Architecture
architecture	I-Architecture
(	O
for	O
example	O
,	O
a	O
CISC	B-Architecture
instruction	B-General_Concept
set	I-General_Concept
architecture	I-General_Concept
such	O
as	O
x86	B-Operating_System
)	O
in	O
which	O
one	O
of	O
the	O
operands	O
for	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>
The	O
earliest	O
example	O
of	O
a	O
load	B-Architecture
–	I-Architecture
store	I-Architecture
architecture	I-Architecture
was	O
the	O
CDC	B-Device
6600	I-Device
.	O
</s>
<s>
Almost	O
all	O
vector	B-Operating_System
processors	I-Operating_System
(	O
including	O
many	O
GPUs	B-Architecture
)	O
use	O
the	O
load	O
–	O
store	O
approach	O
.	O
</s>
