AVM: Slice gadget (hande variable length memory reads + writes)

[IlyasRidhuan]

Many gadget operations, e.g hash permutation function, operates on a slice of information as inputs and/or output.

These slices are likely to be more than our number of current registers (4). Instead of adding more registers, we should be able to dynamically read and write these slices from memory into the gadgets (where the gadget specifies the logic)

Tasks

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1. AVM: CALLDATACOPY gadget #7211
   C-avm +1
   
2. AVM: RETURN opcode gadget #7381
   C-avm +1
   
3. Error handling when memory offset is overflowing #7385
   C-avm +1
   
4. Add unit tests for RETURN gadget #7416
   C-avm T-testing +2
   

[dbanks12]

Is there still work to do on the slice gadget @jeanmon ?

[jeanmon]

Some remaining sub-tasks are still open @dbanks12