1 /*
2 ** $Id: lparser.h,v 1.57.1.1 2007/12/27 13:02:25 roberto Exp $
3 ** Lua Parser
4 ** See Copyright Notice in lua.h
5 */
6
7 #ifndef lparser_h
8 #define lparser_h
9
10 #include "llimits.h"
11 #include "lobject.h"
12 #include "lzio.h"
13
14
15 /*
16 ** Expression descriptor
17 */
18
19 typedef enum {
20 VVOID, /* no value */
21 VNIL,
22 VTRUE,
23 VFALSE,
24 VK, /* info = index of constant in `k' */
25 VKNUM, /* nval = numerical value */
26 VLOCAL, /* info = local register */
27 VUPVAL, /* info = index of upvalue in `upvalues' */
28 VGLOBAL, /* info = index of table; aux = index of global name in `k' */
29 VINDEXED, /* info = table register; aux = index register (or `k') */
30 VJMP, /* info = instruction pc */
31 VRELOCABLE, /* info = instruction pc */
32 VNONRELOC, /* info = result register */
33 VCALL, /* info = instruction pc */
34 VVARARG /* info = instruction pc */
35 } expkind;
36
37 typedef struct expdesc {
38 expkind k;
39 union {
40 struct { int info, aux; } s;
41 lua_Number nval;
42 } u;
43 int t; /* patch list of `exit when true' */
44 int f; /* patch list of `exit when false' */
45 } expdesc;
46
47
48 typedef struct upvaldesc {
49 lu_byte k;
50 lu_byte info;
51 } upvaldesc;
52
53
54 struct BlockCnt; /* defined in lparser.c */
55
56
57 /* state needed to generate code for a given function */
58 typedef struct FuncState {
59 Proto *f; /* current function header */
60 Table *h; /* table to find (and reuse) elements in `k' */
61 struct FuncState *prev; /* enclosing function */
62 struct LexState *ls; /* lexical state */
63 struct lua_State *L; /* copy of the Lua state */
64 struct BlockCnt *bl; /* chain of current blocks */
65 int pc; /* next position to code (equivalent to `ncode') */
66 int lasttarget; /* `pc' of last `jump target' */
67 int jpc; /* list of pending jumps to `pc' */
68 int freereg; /* first free register */
69 int nk; /* number of elements in `k' */
70 int np; /* number of elements in `p' */
71 short nlocvars; /* number of elements in `locvars' */
72 lu_byte nactvar; /* number of active local variables */
73 upvaldesc upvalues[LUAI_MAXUPVALUES]; /* upvalues */
74 unsigned short actvar[LUAI_MAXVARS]; /* declared-variable stack */
75 } FuncState;
76
77
78 LUAI_FUNC Proto *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff,
79 const char *name);
80
81
82 #endif