/* Definitions for bytecode interpretation and compiled-function objects.
   Copyright (C) 1985, 1986, 1987, 1992, 1993 Free Software Foundation, Inc.
   Copyright (C) 2002 Ben Wing.

This file is part of XEmacs.

XEmacs is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.

XEmacs is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with XEmacs.  If not, see <http://www.gnu.org/licenses/>. */

/* Synched up with: Not in FSF. */

/* Authorship:

   FSF: long ago.
   Mly: rewrote for 19.8, properly abstracted.
   Jon Reid: some changes for I18N3 (domain, etc), for 19.8.
 */

#ifndef INCLUDED_bytecode_h_
#define INCLUDED_bytecode_h_

#ifdef NEW_GC
struct compiled_function_args
{
  NORMAL_LISP_OBJECT_HEADER header;
  long size;
  Lisp_Object args[1];
};

typedef struct compiled_function_args Lisp_Compiled_Function_Args;

DECLARE_LISP_OBJECT (compiled_function_args, Lisp_Compiled_Function_Args);

#define XCOMPILED_FUNCTION_ARGS(x) \
  XRECORD (x, compiled_function_args, Lisp_Compiled_Function_Args)
#define wrap_compiled_function_args(p) wrap_record (p, compiled_function_args)
#define COMPILED_FUNCTION_ARGS_P(x) RECORDP (x, compiled_function_args)
#define CHECK_COMPILED_FUNCTION_ARGS(x) \
  CHECK_RECORD (x, compiled_function_args)
#define CONCHECK_COMPILED_FUNCTION_ARGS(x) \
  CONCHECK_RECORD (x, compiled_function_args)

#define compiled_function_args_data(v) ((v)->args)
#define XCOMPILED_FUNCTION_ARGS_DATA(s) \
  compiled_function_args_data (XCOMPILED_FUNCTION_ARGS (s))
#endif /* NEW_GC */

/* Meanings of slots in a Lisp_Compiled_Function.
   Don't use these!  For backward compatibility only.  */
#define COMPILED_ARGLIST	0
#define COMPILED_INSTRUCTIONS	1
#define COMPILED_CONSTANTS	2
#define COMPILED_STACK_DEPTH	3
#define COMPILED_DOC_STRING	4
#define COMPILED_INTERACTIVE	5
#define COMPILED_DOMAIN		6

/* Someone claims: [[ It doesn't make sense to have this and also have
   load-history ]] But in fact they are quite different things.  Perhaps
   we should turn this on only when DEBUG_XEMACS but there's no speed
   harm at all, so no reason not to do it always. */
#define COMPILED_FUNCTION_ANNOTATION_HACK

#ifdef DEBUG_XEMACS
/* Define BYTE_CODE_METER to enable generation of a byte-op usage
   histogram.  This isn't defined in FSF Emacs and isn't defined in XEmacs
   v19.  But this is precisely the thing to turn on when DEBUG_XEMACS.  It
   may lead to a slight speed penalty but nothing major. */
#define BYTE_CODE_METER
#endif

struct Lisp_Compiled_Function
{
  FROB_BLOCK_LISP_OBJECT_HEADER lheader;
  unsigned short stack_depth;
  unsigned short specpdl_depth;
  struct
  {
    unsigned int documentationp: 1;
    unsigned int interactivep: 1;
    /* Only used if I18N3, but always defined for simplicity. */
    unsigned int domainp: 1;
    /* Non-zero if this bytecode came from a v18 or v19 file.
       We need to Ebolify the `assoc', `delq', etc. functions. */
    unsigned int ebolified: 1;
  } flags;
  Lisp_Object instructions;
  Lisp_Object constants;
  Lisp_Object arglist;
  /* For speed, we unroll arglist into an array of argument symbols, so we
     don't have to process arglist every time we make a function call. */
#ifdef NEW_GC
  Lisp_Object arguments;
#else /* not NEW_GC */
  Lisp_Object *args;
#endif /* not NEW_GC */
  /* Minimum and maximum number of arguments.  If MAX_ARGS == MANY, the
     function was declared with &rest, and (args_in_array - 1) indicates
     how many arguments there are before the &rest argument. (We could
     munge the max_non_rest_args into max_args by using a negative number,
     but that interferes with pdump marking.  We don't want to use a flag
     to indicate &rest because that would add an extra check in the
     simplest case.) */
  int min_args, max_args;
  int args_in_array;
  /* This uses the minimal number of conses; see accessors in data.c. */
  Lisp_Object doc_and_interactive;
#ifdef COMPILED_FUNCTION_ANNOTATION_HACK
  /* Something indicating where the bytecode came from */
  Lisp_Object annotated;
#endif
};
typedef struct Lisp_Compiled_Function Lisp_Compiled_Function;

Lisp_Object run_byte_code (Lisp_Object compiled_function_or_instructions, ...);

Lisp_Object compiled_function_arglist       (Lisp_Compiled_Function *f);
Lisp_Object compiled_function_instructions  (Lisp_Compiled_Function *f);
Lisp_Object compiled_function_constants     (Lisp_Compiled_Function *f);
int         compiled_function_stack_depth   (Lisp_Compiled_Function *f);
Lisp_Object compiled_function_documentation (Lisp_Compiled_Function *f);
Lisp_Object compiled_function_annotation    (Lisp_Compiled_Function *f);
Lisp_Object compiled_function_domain        (Lisp_Compiled_Function *f);
Lisp_Object compiled_function_interactive   (Lisp_Compiled_Function *f);

void set_compiled_function_documentation (Lisp_Compiled_Function *f,
					  Lisp_Object new_doc);

void optimize_compiled_function (Lisp_Object compiled_function);

typedef unsigned char Opbyte;
Lisp_Object execute_optimized_program (const Opbyte *program,
#ifdef ERROR_CHECK_BYTE_CODE
				       Elemcount program_length,
#endif
				       int stack_depth,
				       Lisp_Object *constants_data);

DECLARE_LISP_OBJECT (compiled_function, Lisp_Compiled_Function);
#define XCOMPILED_FUNCTION(x) XRECORD (x, compiled_function, \
				       Lisp_Compiled_Function)
#define wrap_compiled_function(p) wrap_record (p, compiled_function)
#define COMPILED_FUNCTIONP(x) RECORDP (x, compiled_function)
#define CHECK_COMPILED_FUNCTION(x) CHECK_RECORD (x, compiled_function)
#define CONCHECK_COMPILED_FUNCTION(x) CONCHECK_RECORD (x, compiled_function)

extern Lisp_Object Qbyte_code;

/* total 1765 internal 101 doc-and-int 775 doc-only 389 int-only 42 neither 559
 no doc slot, no int slot
    overhead                        : (* 1765 0) =    0
    doc-and-int (args . (doc . int)): (*  775 4) = 3100
    doc-only    (args . doc)        : (*  389 2) =  778
    int-only    (args . int)        : (*   42 2) =   84
    neither     args                : (*  559 0) =    0 = 3962
 combined
    overhead                        : (* 1765 1) = 1765
    doc-and-int (doc . int)         : (*  775 2) = 1550
    doc-only    doc                 : (*  389 0) =    0
    int-only    int                 : (*   42 0) =    0
    neither     -                   : (*  559 0) =    0 = 3315
 both
    overhead                        : (* 1765 2) = 3530
    doc-and-int -                   : (*  775 0) =    0
    doc-only    -                   : (*  389 0) =    0
    int-only    -                   : (*   42 0) =    0
    neither     -                   : (*  559 0)  =   0 = 3530
*/

#endif /* INCLUDED_bytecode_h_ */