LOAD Instruction Property

The load (LOAD) instruction copies the value at memory cell #source to memory cell #dst, where source is

(value in memory cell #addr) + imm

More formally:

A simple copy instruction would just copy the value in cell #addr to cell #dst. But instead of using addr as the source, this uses the value stored in cell #addr as the source. You can also add a constant value to offset the source address.

Here is an example:

Initially, the PC is 0, so instruction #0 is executed. Instruction #0 is a LOAD instruction. The destination is memory cell #5. Now lets compute the source cell number. addr is 1, so first look in cell #1, which contains 3. Then add the imm, which is 1.

3 + 1 = 4

Thus, the source is cell #4, which is 9. 9 is copied to the destination, which is cell #5. This example can be expressed as:

if the following are true:

• instruction #0 is load dst=5 addr=1 imm=1
• the PC at time 0 = 0

then value of cell 5 at time (0 + 1) = value of cell ((value of cell 1 at time 0) + 1) at time 0

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