Compiler/code generator: Difference between revisions

=={{header|M2000 Interpreter}}==

<lang M2000 Interpreter>

Module CodeGenerator (s$){

Function code$(op$) {

=format$("{0::-6} {1}", pc, op$)

pc++

}

Function code2$(op$, n$) {

=format$("{0::-6} {1} {2}", pc, op$, n$)

pc+=5

}

Function code3$(op$,pc, st, ed) {

=format$("{0::-6} {1} ({2}) {3}", pc, op$, ed-st-1, ed)

}

Enum tok {

gneg, gnot, gmul, gdiv, gmod, gadd, gle, gsub, glt

gle, ggt, gge, geq, gne, gand, gor, gputc, gprti, gprts,

gif, gwhile, gAssign, gSeq, gstring, gidentifier, gint, gnone

}

\\ Inventories are list with keys, or keys/data (key must be unique)

\\ there is one type more the Invetory Queue which get same keys.

\\ But here not used.

Inventory symb="Multiply":=gmul, "Divide":=gdiv, "Mod":=gmod, "Add":=gadd

Append symb, "Negate":=gneg, "Not":=gnot,"Less":=glt,"Subtract":=gsub

Append symb, "LessEqual":=gle, "Greater":=ggt, "GreaterEqual":=gge, "Sequence":=gSeq

Append symb, "Equal":=geq, "NotEqual":=gne, "And":=gand, "Or":=gor, "While":=gwhile

Append symb, "Putc":=gputc,"Prti":=gprti,"Prts":=gprts, "Assign":=gAssign, "If":=gif

Append symb, "String":=gstring, "Identifier":=gidentifier, "Integer":=gint, ";", gnone

Inventory DataSet

\\ We set string as key. key maybe an empty string, a string or a number.

\\ so we want eash string to saved one time only.

Inventory Strings

Const nl$=chr$(13)+chr$(10), Ansi=3

Def z$, lim, line$, newvar_ok, i=0

Document message$=nl$

Global pc \\ functions have own scope, so we make it global, for this module, and childs.

Dim lines$()

s$=filter$(s$,chr$(9)) \\ exclude tabs

Lines$()=piece$(s$,nl$) \\ break to lines

lim=len(Lines$())

Flush ' empty stack (there is a current stack of values which we use here)

Load_Ast()

If not stack.size=1 Then Flush : Error "Ast not loaded"

AST=array \\ pop the array from stack

Document Assembly$, Header$

\\ all lines of assembly goes to stack. Maybe not in right order.

\\ Push statement push to top, Data statement push to bottom of stack

CodeGenerator(Ast)

Data code$("halt") ' append to end of stack

\\ So now we get all data (letters) from stack

While not empty

Assembly$=letter$+nl$

end while

\\ So now we have to place them in order

Sort Assembly$

\\ Let's make the header

Header$=format$("Datasize: {0} Strings: {1}", Len(Dataset),Len(strings))+nl$

\\ we use an iterator object, str^ is the counter, readonly, but Eval$() use it from object.

str=each(strings)

While str

Header$=Eval$(str)

If str^<len(strings)-1 then Header$=nl$

End while

\\ insert to line 1 the Header

Insert 1 Assembly$=Header$

\\ Also we check for warnings

If len(message$)>2 then Assembly$="Warnings: "+nl$+message$

\\ So now we get a report

\\ (at each 3/4 of window's lines, the printing stop and wait for user response, any key)

Report Assembly$

Clipboard Assembly$

Save.Doc Assembly$, "code.t", Ansi

End

\\ subs have 10000 limit for recursion but can be extended to 1000000 or more.

Sub CodeGenerator(t)

If len(t)=3 then

select case t#val(0)

Case gSeq

CodeGenerator(t#val(1)) : CodeGenerator(t#val(2))

Case gwhile

{

local spc=pc

CodeGenerator(t#val(1))

local pc1=pc

pc+=5 ' room for jz

CodeGenerator(t#val(2))

data code3$("jz",pc1, pc1, pc+5)

data code3$("jmp",pc, pc, spc)

pc+=5 ' room for jmp

}

Case gif

{

CodeGenerator(t#val(1))

local pc1=pc, pc2

pc+=5

CodeGenerator(t#val(2)#val(1))

If len(t#val(2)#val(2))>0 then

pc2=pc

pc+=5

data code3$("jz",pc1, pc1, pc)

CodeGenerator(t#val(2)#val(2))

data code3$("jz",pc2, pc2, pc)

else

data code3$("jz",pc1, pc1, pc)

end If

}

Case gAssign

{

CodeGenerator(t#val(2))

local newvar_ok=true

CodeGenerator(t#val(1))

}

case gneg to gnot, gputc to gprts

CodeGenerator(t#val(1)) : data code$(mid$(eval$(t#val(0)),2))

case gmul to gor

{

CodeGenerator(t#val(1))

CodeGenerator(t#val(2))

data code$(mid$(eval$(t#val(0)),2))

}

End select

Else.if len(t)=2 then

select case t#val(0)

Case gString

{

local spos

If exist(strings,t#val$(1)) then

spos=eval(strings!)

else

append strings, t#val$(1)

spos=len(strings)-1

end If

Push code2$("push",str$(spos,0))

}

Case gInt

Push code2$("push",t#val$(1), pc)

Case gIdentifier

{

local ipos

If exist(dataset,t#val$(1)) then

ipos=Eval(dataset!) ' return position

else.if newvar_ok then

Append dataset, t#val$(1)

ipos=len(dataset)-1

else

message$="Variable "+t#val$(1)+" not initialized"+nl$

end If

If newvar_ok then

Push code2$("store","["+str$(ipos, 0)+"]")

else

Push code2$("fetch","["+str$(ipos, 0)+"]")

end If

}

end select

End If

End Sub

Sub Load_Ast()

If i>=lim then Push (,) : exit sub

do

line$=Trim$(lines$(i))

I++

tok$=piece$(line$," ")(0)

until line$<>"" or i>=lim

If tok$="Identifier" then

Push (gidentifier, piece$(line$," ")(1))

else.if tok$="Integer" then

long n=Val(piece$(line$," ")(1)) ' check overflow

Push (gint, piece$(line$," ")(1))

else.if tok$="String" then

Push (gstring,Trim$(Mid$(line$,7)))

else.if tok$=";" then

Push (,)

Else

local otok=symb(tok$)

Load_Ast()

Load_Ast()

Shift 2

Push (otok,array, array)

End If

End Sub

}

CodeGenerator {

Sequence

Sequence

;

Assign

Identifier count

Integer 1

While

Less

Identifier count

Integer 10

Sequence

Sequence

;

Sequence

Sequence

Sequence

;

Prts

String "count is: "

;

Prti

Identifier count

;

Prts

String "\n"

;

Assign

Identifier count

Add

Identifier count

Integer 1

}

</lang>

{{out}}

<pre style="height:30ex;overflow:scroll">

Datasize: 1 Strings: 2

"count is: "

"\n"

0 push

5 store [0]

10 fetch [0]

15 push

20 lt

21 jz (43) 65

26 push 0

31 prts

32 fetch [0]

37 prti

38 push 1

43 prts

44 fetch [0]

49 push

54 add

55 store [0]

60 jmp (-51) 10

65 halt

</pre >