Difference between revisions of "VM for transfer"

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* The case is represented as "aa" (all lowercase), "Aa" (first uppercase) and "AA", (all uppercase).
* The case is represented as "aa" (all lowercase), "Aa" (first uppercase) and "AA", (all uppercase).


== Code generation ==
== Sample compilation of XML code fragments ==

=== Example 1 ===
==== XML t1x Code: chunking ====
<code>
<out>
<chunk name="det_det_nom_adj" case="caseFirstWord">
<tags>
<tag><lit-tag v="SN"/></tag>
<tag><var n="tipus_det"/></tag>
<tag><var n="gen_chunk"/></tag>
<tag><var n="nbr_chunk"/></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>
<b/>
<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>
<b pos="1"/>
<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>
<b/>
<b pos="2"/>
<lu>
<var n="adjectiu1"/>
<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>
</code>

==== Compiled Code ====

<code>
push "det_det_nom_adj"
push "<SN>"
pusht tipus_det ; first evaluate the variable, append/prepend '<>', then push in the stack
pusht gen_chunk
pusht nbr_chunk
push 1
push "^\w+" ; lem
cliptl
push 1
push [regex] ; a_det
cliptl
push "<3>" ; since link-to overrides everything else, we do not need any dedicated instruction
; for that
push 1
push [regex] ; gen_mf
cliptl
push "<4>"
push 1
push [regex] ; nbr_sp
cliptl
lu 6 ; pop 6 items, concat, create lexical unit ^...$ and push back in stack
pushbl ; push a blank
push "el"
push "<det><def>"
push "<3>"
push "<pl>"
lu 4 ; pop 4 items from the stack, create a lexical unit ^...$ and then
; push in the stack
pushsb 1
push 3
push [regex] ; lemh
cliptl
push 3
push [regex] ; a_nom
cliptl
push "<3>"
push 3
push [regex] ; gen_mf
cliptl
push "<4>"
push 3
push [regex] ; nbr_sp
cliptl
push 3
push [regex] ; lemq
cliptl
lu 7
pushbl
pushsb 2
pushv adjectiu1 ; its a var, so eval and push the value
push 3
push [regex] ; lemh
cliptl
push 3
push [regex] ; a_adj
cliptl
push "<3>"
push 3
push [regex] ; gen_mf
cliptl
push "<4>"
push "<4>" ; a bit confused, there are two link-to in the XML
push 3
push [regex] ; lemq
cliptl
lu 7
brace 7 ; no of blank + lexical unit = 7
; pop 7 items, concat, prepend and append {, } then push back
chunk 6 ; create the chunk, ^...{^...$}$, and push back in stack
out 1 ; give output (number of chunks = 1)
</code>

=== Example 2 ===

==== XML t1x Code ====
<code>
<section-def-cats>
<def-cat n="nom">
<cat-item tags="n.*"/>
</def-cat>
<def-cat n="det">
<cat-item tags="det.*"/>
<cat-item tags="predet.*"/>
</def-cat>
</section-def-cats>
<section-rules>
<rule>
<pattern>
<pattern-item n="det"/>
</pattern>
</rule>
<rule>
<pattern>
<pattern-item n="nom"/>
</pattern>
<action/>
</rule>
<rule>
<pattern>
<pattern-item n="det"/>
<pattern-item n="nom"/>
</pattern>
<action/>
</rule>
</section-rules>
</code>

==== Compiled Code ====

<code>
;first rule: def-cat has two equivalent cat-items
push "\w<det>\t" ;load pattern into stack
push 1
addtrie [address1] ;define a trie pattern with value 1 (the first rule)
push "\w<predet>\t" ;same with the second cat-item
push 1
addtrie [address1]
;second rule (and so on) very simple, unique cat-item
push "\w<n>\t"
push 1
addtrie [address2]
;third rule (here is the trick: multiple cat-items in one of the words)
push "\w<det>\t"
push "\w<n>\t"
push 2 ; we have 'det' followed by a 'nom', so addtrie has to pop two elements
addtrie [address3]
push "\w<predet>\t"
push "\w<n>\t"
push 2
addtrie [address3]
</code>

=== Example 3 ===
==== XML t1x Code ====

<code>
<def-macro n="f_coma" npar="1">
<choose>
<when>
<test>
<equal caseless="yes">
<clip pos="1" side="sl" part="lem"/>
<lit v="como"/>
</equal>
</test>
<let>
<clip pos="1" side="tl" part="lem"/>
<get-case-from pos="1">
<lit v="com a"/>
</get-case-from>
</let>
</when>
</choose>
</def-macro>
</code>

==== Compiled code ====

<code>
f_coma: push 1 ; "pos" of "clip"
push "^\w+" ; "lem"
clipsl ; gets the value clips on the top of the stack.
; "sl" side is implied in the name of the instruction
push "como"
cmpi ; does the comparison and cleans the stack, it means caseless
jnz end ; if the comparison does not succeeds, go to end
; semantics: j = jump n = not z = zero flag is activated
; zero flag is activated when a comparison succeeds
; or an arithmetical operation gives 0
push 1 ; "pos" of "clip"
push "^\w+"
push "com a"
storetl ; store the value provided in the top of the stack
; given position 1, "tl" side and "lem"
end: ...
</code>

=== Example 4 ===
==== XML t1x Code ====
<code>
<test>
<or>
<not>
<equal>
<clip pos="1" side="sl" part="gen"/>
<clip pos="3" side="sl" part="gen"/>
</equal>
</not>
<not>
<equal>
<clip pos="2" side="sl" part="gen"/>
<clip pos="3" side="sl" part="gen"/>
</equal>
</not>
</or>
</test>
</code>
==== Compiled code ====

<code>
start: push 1
push [regex] ; part="gen"
clipsl
push 3
push [regex] ; part="gen"
clipsl
cmp ; compare (case sensitive)
pushnz ; NOT zero flag and push in stack
push 2
push [regex] ; part="gen"
clipsl
push 3
push [regex] ; part="gen"
clipsl
cmp ; compare (case sensitive)
pushnz
or ; pop 2 items and OR, push result in stack
jnz end ; jump if zero flag is 0 (we did not get ZERO as the result)
... ... ...
(code for successful test)
... ... ...
end: ...
</code>

=== Example 5 ===
==== XML t1x Code ====
<def-list n="verbos_est">
<list-item v="actuar"/>
<list-item v="buscar"/>
<list-item v="estudiar"/>
<list-item v="existir"/>
<list-item v="ingressar"/>
<list-item v="introduir"/>
<list-item v="penetrar"/>
<list-item v="publicar"/>
<list-item v="treballar"/>
<list-item v="viure"/>
</def-list>
<rule>
<pattern>
<pattern-item n="verb"/>
<pattern-item n="a"/>
</pattern>
<action>
<choose>
<when>
<test>
<in caseless="yes"/>
<clip pos="1" side="sl" part="lem"/>
<list n="verbos_est"/>
</in>
</test>
<let>
<clip pos="2" side="tl" part="lem"/>
<lit v="en"/>
</let>
</when>
</choose>
</rule>

==== Compiled code ====
push "actuar"
push "buscar"
push "estudiar"
push "existir"
push "ingressar"
push "introduir"
push "penetrar"
push "publicar"
push "treballar"
push "viure"
push 10 ; number of elements in the list
mklist verbos_est ; make a list variable named 'verbos_est' and put the last 10 data
; from the stack in the list
rule1: push [regex_verb]
push [regex_a]
push 2
addtrie rule1_action
... ... ...
... ... ...
rule1_action: push 1
push "^\w+" ; lem
clipsl ; we have lemmma in stack now
incini verbox_est ; if in verbos_est (ignore case), set ZF = 1, else ZF = 0
jnz rule1_end
push 2
push "^\w+"
push "en"
storetl
rule1_end: ...

=== Example 6 ===
==== XML t1x Code ====
<def-macro n="firstWord" npar="1">
<choose>
<when>
<test>
<equal>
<clip pos="1" side="sl" part="a_np_acr"/>
<lit v=""/>
</equal>
</test>
<choose>
<when>
<test>
<equal>
<var n="EOS"/>
<lit v="true"/>
</equal>
</test>
<modify-case>
<clip pos="1" side="tl" part="lem"/>
<lit v="aa"/>
</modify-case>
<let>
<var n="caseFirstWord"/>
<lit v="Aa"/>
</let>
</when>
<otherwise>
<let>
<var n="caseFirstWord"/>
<lit v="aa"/>
</let>
</otherwise>
</choose>
</when>
<otherwise>
<let>
<var n="caseFirstWord"/>
<lit v="aa"/>
</let>
</otherwise>
</choose>
<let>
<var n="EOS"/>
<lit v="false"/>
</let>
</def-macro>
<rule comment="REGLA: DET DET ADJ NOM (your many beautiful cats)">
... ...
<action>
<call-macro n="firstWord">
<with-param pos="1"/>
</call-macro>
<call-macro n="f_concord4">
<with-param pos="4"/>
<with-param pos="3"/>
<with-param pos="2"/>
<with-param pos="1"/>
</call-macro>
...
<out>
<chunk name="det_det_nom_adj" case="caseFirstWord">
... ...
</chunk>
</out>
</action>
</rule>

==== Compiled code ====

firstWord:
... ... ; normal translation of instructions, all the variables are assumed global
... ...
ret ; ret instruction does a number of things
; pops 'frame stack', current 'local variable frame' is reset with popped
; values (actually its more pointer assignment), C++ version will also
; do the necessary deallocations
; pops global stack, update PC with the popped value
... ...
... ...
rule_ddan_action: push 1 ; pos = 1
push 1 ; number of parameters 1
call firstWord ; macro label
; call statement does a number of things
; 1. temppc = PC + 1, set PC = firstWord
; 2. pushes the current 'local variable frame' into 'frame stack'
; 3. create a new 'local variable frame'
; 4. pops the arguments from the stack and places then in the 'local
; variable frame'
; 5. pushes temppc in global stack (it will be used by the return
; statement)
; 6. continue (instruction at firstWord will be evaluated next)
push 1 ; notice that the arguments are pushed in reverse order
; when popped, they will be in the right order
push 2
push 3
push 4
push 4
call f_concord4
... ...

== Development Notes ==

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

* The local variable frame is actually a queue with a maximum length equal to the maximum pattern length in the trie.

Revision as of 08:38, 12 July 2011

Instruction Set

Mnemonic Opcode
(in hex)
Other operands Stack
[before]→[after] (top, top-1, ...)
Description
push - value [empty] → value Pushes a string or a variable value onto the stack. Strings go between quotes ("string") but variable's names not
pushbl - N/A [empty] → blank Pushes a blank onto the stack
pushsb - pos [empty] → superblank Pushes the superblank at 'pos' onto the stack
append - N valueN, ..., value1, varName → [empty] Pops 'N' elements and appends them to a variable or clip
concat - N valueN, ..., value1 → value1...valueN Pops 'N' elements and pushes them back concatenated
clip - N/A part → value Obtains the part in the only language there is (inter/post-chunk) and pushes the value onto the stack
clipsl - N/A part, pos → value Obtains the 'part' in source language in position 'pos' and pushes the 'value' onto the stack
cliptl - N/A part, pos → value Obtains the 'part' in target language in position 'pos' and pushes the 'value' onto the stack
storecl - N/A value, part → [empty] Stores 'value' in the only language there is (inter/post-chunk)
storesl - N/A value, part, pos → [empty] Stores 'value' as the 'part' of the source language in position 'pos'
storetl - N/A value, part, pos → [empty] Stores 'value' as the 'part' of the target language in position 'pos'
storev - N/A value, varName → [empty] Stores 'value' in the variable with name 'varName'
addtrie - address N, patternN, ..., pattern1 → [empty] Pops 'N' patterns and creates a trie entry pointing to 'address'
lu - N valueN, ..., value1 → ^(lexical_unit)$ Pops 'N' values from the stack, creates a lexical unit ^...$ with them and pushes the lu back onto the stack
mlu - N luN, ..., lu1 → multiword Pops 'N' lu from the stack, creates a multiword with them and pushes the multiword back onto the stack
lu-count - N/A [empty] → number Pushes the number of lexical units (words inside the chunk) in the rule onto the stack
chunk - N elemN-2, ... , elem1, <tags>, name → ^name<tags>{elem1...elemN-2}$ Pops 'N' amount of data from the stack, creates the chunk and pushes it back onto the stack
out - N valueN, ..., value1 → [empty] Pops 'N' values from the stack and outputs them
cmp - N/A value2, value1 → result Pops 'value1' and 'value2', compares them, if they are equal pushes a 1 (true), if they aren't pushes a 0 (false)
cmpi - N/A value2, value1 → result Pops 'value1' and 'value2', compares them (ignoring case for each string), if they are equal pushes a 1 (true), if they aren't pushes a 0 (false)
cmp-substr - N/A value2, value1 → result Tests if 'value1' contains the substring 'value2', result can be 1 (true) or 0 (false).
cmpi-substr - N/A value2, value1 → result Tests if 'value1' contains the substring 'value2' (ignoring case for each string), result can be 1 (true) or 0 (false).
not - N value → result Negates the value on top of the stack, 0 -> 1 or 1 -> 0
and - N valueN, ..., value1 → result And operation of 'N' values, result can be 1 (true) or 0 (false)
or - N valueN, ..., value1 → result Or operation of 'N' values, result can be 1 (true) or 0 (false)
in - N/A list, value → result Performs a search of a 'value' in a 'list'
inig - N/A list, value → result Performs a search (ignoring case) of a 'value' in a 'list'
jmp - label [empty] → [empty] Jumps to the label, unconditionally
jz - label top → [empty] Jumps to the label if stack.top == 0
jnz - label top → [empty] Jumps to the label if stack.top == 1
call - label N, argN, ..., arg1 → [empty] Calls a macro with the arguments on the stack
ret - N/A [empty] → [empty] Returns from a macro, PC will be handled automatically by the VM.
nop - N/A [empty] → [empty] No operation
case-of - N/A container → case Gets the case from the container in the stack. The container would usually be the result of a clip instruction but can be any string.
get-case-from - N/A pos → case Gets the case from the lexical unit in position 'pos'
modify-case - N/A case, container → modifiedContainer Modifies the case of the 'container' to 'case' and leaves the modified container on the stack
begins-with - N/A value2, value1 → result Checks if 'value1' begins with 'value2' and pushes 1 (true) or 0 (false), 'value2' can be a list
begins-with-ig - N/A value2, value1 → result Checks if 'value1' begins with 'value2' (ignoring the case) and pushes 1 (true) or 0 (false), 'value2' can be a list
ends-with - N/A value2, value1 → result Checks if 'value1' ends with 'value2' and pushes 1 (true) or 0 (false), 'value2' can be a list
ends-with-ig - N/A value2, value1 → result Checks if 'value1' ends with 'value2' (ignoring the case) and pushes 1 (true) or 0 (false), 'value2' can be a list
  • Lists are represented as a concatenation of items separated by '|', e.g. uno|otro|poco|cuánto|menos|mucho|tanto|demasiado
  • The case is represented as "aa" (all lowercase), "Aa" (first uppercase) and "AA", (all uppercase).

Code generation