lua/lparser.h
2002-03-25 14:47:14 -03:00

83 lines
2.3 KiB
C

/*
** $Id: lparser.h,v 1.40 2002/03/14 18:01:52 roberto Exp roberto $
** Lua Parser
** See Copyright Notice in lua.h
*/
#ifndef lparser_h
#define lparser_h
#include "llimits.h"
#include "lobject.h"
#include "ltable.h"
#include "lzio.h"
/*
** Expression descriptor
*/
typedef enum {
VVOID, /* no value */
VNIL,
VTRUE,
VFALSE,
VK, /* info = index of constant in `k' */
VLOCAL, /* info = local register */
VUPVAL, /* info = index of upvalue in `upvalues' */
VGLOBAL, /* info = index of table; aux = index of global name in `k' */
VINDEXED, /* info = table register; aux = index register (or `k') */
VRELOCABLE, /* info = instruction pc */
VNONRELOC, /* info = result register */
VJMP, /* info = result register */
VCALL /* info = result register */
} expkind;
typedef struct expdesc {
expkind k;
int info, aux;
int t; /* patch list of `exit when true' */
int f; /* patch list of `exit when false' */
} expdesc;
/* describe declared variables */
typedef struct vardesc {
int i; /* if local, its index in `locvars';
if global, its name index in `k' */
lu_byte k;
lu_byte level; /* if local, stack level;
if global, corresponding local (NO_REG for free globals) */
} vardesc;
struct BlockCnt; /* defined in lparser.c */
/* state needed to generate code for a given function */
typedef struct FuncState {
Proto *f; /* current function header */
Table *h; /* table to find (and reuse) elements in `k' */
struct FuncState *prev; /* enclosing function */
struct LexState *ls; /* lexical state */
struct lua_State *L; /* copy of the Lua state */
struct BlockCnt *bl; /* chain of current blocks */
int pc; /* next position to code (equivalent to `ncode') */
int lasttarget; /* `pc' of last `jump target' */
int jlt; /* list of jumps to `lasttarget' */
int freereg; /* first free register */
int defaultglob; /* where to look for non-declared globals */
int nk; /* number of elements in `k' */
int np; /* number of elements in `p' */
int nlocvars; /* number of elements in `locvars' */
int nactloc; /* number of active local variables */
int nactvar; /* number of elements in array `actvar' */
expdesc upvalues[MAXUPVALUES]; /* upvalues */
vardesc actvar[MAXVARS]; /* declared-variable stack */
} FuncState;
Proto *luaY_parser (lua_State *L, ZIO *z);
#endif