VM for transfer

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Instruction Sets

Mnemonic Opcode
(in hex)
Other operands Stack
[before]→[after]
Description
push - value [empty] → value Pushes a value in the stack
jmp - N/A label → [empty] Jumps to the label
hlt - N/A Halts the program
return - N/A PC → [empty] Returns from a subroutine

Notes

  • None of the macro and actions need to return anything (unlike conventional functions), so provision for returning a value (using stack) is unnecessary

Sample Translation from XML to byte-code

       <out>
         <chunk name="det_det_nom_adj" case="caseFirstWord">
       <tags>
         <tag><lit-tag v="SN"/></tag>
         <tag></tag>
         <tag></tag>
         <tag></tag>
       </tags>
       <lu>
         <clip pos="1" side="tl" part="lem"/>
         <clip pos="1" side="tl" part="a_det"/>
         <clip pos="1" side="tl" part="gen_sense_mf" link-to="3"/>
         <clip pos="1" side="tl" part="gen_mf"/>
         <clip pos="1" side="tl" part="nbr_sense_sp" link-to="4"/>
         <clip pos="1" side="tl" part="nbr_sp"/>
       </lu>
       
       <lu>
         <lit v="el"/>
         <lit-tag v="det.def"/>
         <clip pos="1" side="tl" part="gen_sense_mf" link-to="3"/>
         <lit-tag v="pl"/>
       </lu>
       
       <lu>
         <clip pos="3" side="tl" part="lemh"/>
         <clip pos="3" side="tl" part="a_nom"/>
         <clip pos="3" side="tl" part="gen_sense_mf" link-to="3"/>
         <clip pos="3" side="tl" part="gen_mf"/>
         <clip pos="3" side="tl" part="nbr_sense_sp" link-to="4"/>
         <clip pos="3" side="tl" part="nbr_sp"/>
         <clip pos="3" side="tl" part="lemq"/>
       </lu>
       
       
       <lu>
         
         <clip pos="2" side="tl" part="lemh"/>
         <clip pos="2" side="tl" part="a_adj"/>
         <clip pos="2" side="tl" part="gen_sense_mf" link-to="3"/>
         <clip pos="2" side="tl" part="gen_mf"/>
         <clip pos="2" side="tl" part="nbr_sense_sp" link-to="4"/>
         <clip pos="2" side="tl" part="nbr_sp" link-to="4"/>
         <clip pos="2" side="tl" part="lemq"/>
       </lu>
         </chunk>
       </out>

Byte-code

push    "det_det_nom_adj"
pusht   "SN"               ; "SN" -> "<SN>", then push in the stack
pusht   tipus_det          ; if operand does not start/end with ", then it's a variable
                           ; first evaluate the variable, then push in the stack
pusht   gen_chunk
pusht   nbr_chunk
concat  5                  ; pop 5 items from stack, concat and push as one item

push    1
push    "^\w+"             ; lem
cliptl
push    1
push    [regex]            ; a_det
cliptl
linkto  3                  ; <3> since link-to overrides everything else, we are using a dedicated
                           ; instruction for it
push    1
push    [regex]            ; gen_mf
cliptl
linkto  4
push    1
push    [regex]            ; nbr_sp
cliptl
concat  6