Replacing veneer routines?

Authoring Inform 6
1

I’m experimenting a bit with the Inform6 compiler. I’ve added a printout of which veneer-routines that gets compiled into the output.

Compiling veneer routines:
  RV__Pr
  CA__Pr
  RA__Pr
  RL__Pr
  OP__Pr
  OC__Cl
  Copy__Primitive
  RT__Err
  Z__Region
  Unsigned__Compare
  Meta__class
  CP__Tab
  Cl__Ms
  Print__PName

How do I do if I would want to have my own version of one of these?

If I add my own version of the routine CL__Ms, I get a warning that it’s never called (and possibly is it removed if I choose $OMIT_UNUSED_ROUTINES=1). The compiler recognizes that I have the routine replaced and don’t insert the veneer one.

source\new_veneer.inf(19): Warning:  Routine "Cl__Ms" declared but not used

Compiling veneer routines:
  RV__Pr
  CA__Pr
  RA__Pr
  RL__Pr
  OP__Pr
  OC__Cl
  Copy__Primitive
  RT__Err
  Z__Region
  Unsigned__Compare
  Meta__class
  CP__Tab
  Print__PName

What am I doing wrong?

2

I don’t know, you didn’t say what your code looks like.

This works without warnings:

Replace CL__Ms;

[ CL__Ms;
	print "Replaced function.^";
];

[ Main;
	TestFunc();
];

Class TestClass;

[ TestFunc;
	print "Hello.^";
	TestClass.create();
];
3

Well it is a full fledge game. I’ll try your test with my switches when I’m back home.

4

The Replace line and the new definition should appear before any other code.

5

Are you only saying this with respect to veneer routines? I’ve been replacing action routines (like GoSub, LockSub and UnlockSub) for years and I always put them at the end of my code, along with all the other action routines.

6

Veneer routines behave slightly differently, so probably.

1 Like
7

When replacing a veneer function like RV__Pr, is there a way to make expressions like obj.#identifier <= 2 to compile with native syntax (get_prop_addr and get_prop_len) or do I have to use the opcodes myself with the @-syntax? Now it calls itself and fills up the stack.

[ RV__Pr obj identifier x;
 x = obj..&identifier;
 if (x==0)
 {   if (identifier >= 1 && identifier < 64 && obj.#identifier <= 2)
		 return obj.identifier;
	 !RT__Err(\"read\", obj, identifier); return; 
 }
 #IFV3;
 !if (obj..#identifier > 2) RT__Err(\"read\", obj, identifier);
 #IFNOT;
 !if (obj..#identifier > 2) RT__Err(\"read\", obj, identifier, 2);
 #ENDIF;
 return x-->0;
];

Compiles in veneer:

    1  +11f18  [ RV__Pr obj identifier x

    1  +11f19     call_vs      long_16 (veneer routine: RA__Pr) obj identifier -> x
    1  +11f20     jz           x to L0 if FALSE
    1  +11f24     jl           identifier short_1 to L1 if TRUE
    1  +11f29     jl           identifier short_64 to L1 if FALSE
    1  +11f2e     get_prop_addr obj identifier -> TEMP1
    1  +11f32     jz           TEMP1 to L2 if TRUE
    1  +11f36     get_prop_len TEMP1 -> TEMP1
    1  +11f39    .L2
    1  +11f39     push         TEMP1
    1  +11f3c     jg           sp short_2 to L1 if TRUE
    1  +11f41     get_prop     obj identifier -> TEMP1
    1  +11f45     push         TEMP1
    1  +11f48     ret_popped
    1  +11f49    .L1
    1  +11f49     call_vn      long_2037 (ref to symbol value: RT__Err) long_33961 (string literal) obj identifier
    1  +11f51     rtrue
    1  +11f52    .L0
    1  +11f52     call_vs      long_17 (veneer routine: RL__Pr) obj identifier -> sp
    1  +11f59     jg           sp short_2 to L3 if FALSE
    1  +11f5e     call_vn2     long_2037 (ref to symbol value: RT__Err) long_33962 (string literal) obj identifier short_2
    1  +11f68    .L3
    1  +11f68     loadw        x short_0 -> sp
    1  +11f6c     ret_popped

And when it’s replaced:

   23  +11d7c  [ RV__Pr obj identifier x

   25  +11d7d <*> call_vs      long_16 (veneer routine: RA__Pr) obj identifier -> x
   27  +11d84 <*> jz           x to L0 if FALSE
   29  +11d88 <*> jl           identifier short_1 to L1 if TRUE
   29  +11d8d     jl           identifier short_64 to L1 if FALSE
   29  +11d92     call_vs      long_17 (veneer routine: RL__Pr) obj identifier -> sp
   29  +11d99     jg           sp short_2 to L1 if TRUE
   31  +11d9e <*> call_vs      long_10 (veneer routine: RV__Pr) obj identifier -> sp
   31  +11da5     ret_popped
   31  +11da6    .L1
   45  +11da6    .L0
   47  +11da6 <*> loadw        x short_0 -> sp
   47  +11daa     ret_popped
1 Like
8

You have to use the opcodes.

1 Like