Then, the store operation and the address computation for next element can be combined by the one store instruction with post-indexed addressing mode 'STRB R3, [R1], #1' as shown in Fig.
This is because the program uses many LSL (Logical Shift Left) and ADD instructions for address computation that can be eliminated in AMEX16.
There are two approaches to this computation for discrete images: forward and reverse address computation. In the forward approach, [u.sub.q] and [v.sub.p] are computed for each input pixel (p,q) and substituted into Eq.
If [s.sub.x] and [s.sub.y] are each greater than unity, the address computation of Eq.
Rotation: Rotation of an input image about its Cartesian (21) origin can be accomplished by the address computation
These requirements make the died address computation efficient with a minor expense of resources.
The additional system performance cost of tiled address computation is presumed acceptable in light of the reduced i/o.
The first implementations of tiling by McKellar  buried the additional address computations in the matrix arithmetic algorithms(3) being studied.
For the non-tiled versions, macros are provided that perform non-tiled address computations.
Returning to the general case, the address computation can be implemented in several ways.
Given the address computation algorithm, retrieval and insertion of an element is straightforward.
The address computation of spiral storage is illustrated in Figure 5.