/*
** $Id: lparser.h,v 1.70.1.1 2013/04/12 18:48:47 roberto Exp $
** Lua Parser
** See Copyright Notice in lua.h
*/
#ifndef lparser_h
#define lparser_h
#include "llimits.h"
#include "lobject.h"
#include "lzio.h"
/*
** Expression descriptor
*/
typedef enum {
VVOID, /* no value */
VNIL,
VTRUE,
VFALSE,
VK, /* info = index of constant in `k' */
VKNUM, /* nval = numerical value */
VNONRELOC, /* info = result register */
VLOCAL, /* info = local register */
VUPVAL, /* info = index of upvalue in 'upvalues' */
VINDEXED, /* t = table register/upvalue; idx = index R/K */
VJMP, /* info = instruction pc */
VRELOCABLE, /* info = instruction pc */
VCALL, /* info = instruction pc */
VVARARG /* info = instruction pc */
} expkind;
#define vkisvar(k) (VLOCAL <= (k) && (k) <= VINDEXED)
#define vkisinreg(k) ((k) == VNONRELOC || (k) == VLOCAL)
typedef struct expdesc {
expkind k;
union {
struct { /* for indexed variables (VINDEXED) */
short idx; /* index (R/K) */
lu_byte t; /* table (register or upvalue) */
lu_byte vt; /* whether 't' is register (VLOCAL) or upvalue (VUPVAL) */
} ind;
int info; /* for generic use */
lua_Number nval; /* for VKNUM */
} u;
int t; /* patch list of `exit when true' */
int f; /* patch list of `exit when false' */
} expdesc;
/* description of active local variable */
typedef struct Vardesc {
short idx; /* variable index in stack */
} Vardesc;
/* description of pending goto statements and label statements */
typedef struct Labeldesc {
TString *name; /* label identifier */
int pc; /* position in code */
int line; /* line where it appeared */
lu_byte nactvar; /* local level where it appears in current block */
} Labeldesc;
/* list of labels or gotos */
typedef struct Labellist {
Labeldesc *arr; /* array */
int n; /* number of entries in use */
int size; /* array size */
} Labellist;
/* dynamic structures used by the parser */
typedef struct Dyndata {
struct { /* list of active local variables */
Vardesc *arr;
int n;
int size;
} actvar;
Labellist gt; /* list of pending gotos */
Labellist label; /* list of active labels */
} Dyndata;
/* control of blocks */
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 BlockCnt *bl; /* chain of current blocks */
int pc; /* next position to code (equivalent to `ncode') */
int lasttarget; /* 'label' of last 'jump label' */
int jpc; /* list of pending jumps to `pc' */
int nk; /* number of elements in `k' */
int np; /* number of elements in `p' */
int firstlocal; /* index of first local var (in Dyndata array) */
short nlocvars; /* number of elements in 'f->locvars' */
lu_byte nactvar; /* number of active local variables */
lu_byte nups; /* number of upvalues */
lu_byte freereg; /* first free register */
} FuncState;
LUAI_FUNC Closure *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff,
Dyndata *dyd, const char *name, int firstchar);
#endif