client/deps/liblua/lparser.h

   1 /*
   2 ** $Id: lparser.h,v 1.70 2012/05/08 13:53:33 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     VNONRELOC,    /* info = result register */
  27     VLOCAL,       /* info = local register */
  28     VUPVAL,       /* info = index of upvalue in 'upvalues' */
  29     VINDEXED,     /* t = table register/upvalue; idx = index R/K */
  30     VJMP,         /* info = instruction pc */
  31     VRELOCABLE,   /* info = instruction pc */
  32     VCALL,        /* info = instruction pc */
  33     VVARARG       /* info = instruction pc */
  34 } expkind;
  35
  36
  37 #define vkisvar(k)   (VLOCAL <= (k) && (k) <= VINDEXED)
  38 #define vkisinreg(k) ((k) == VNONRELOC || (k) == VLOCAL)
  39
  40 typedef struct expdesc {
  41     expkind k;
  42     union {
  43         struct {  /* for indexed variables (VINDEXED) */
  44             short idx;  /* index (R/K) */
  45             lu_byte t;  /* table (register or upvalue) */
  46             lu_byte vt;  /* whether 't' is register (VLOCAL) or upvalue (VUPVAL) */
  47         } ind;
  48         int info;  /* for generic use */
  49         lua_Number nval;  /* for VKNUM */
  50     } u;
  51     int t;  /* patch list of `exit when true' */
  52     int f;  /* patch list of `exit when false' */
  53 } expdesc;
  54
  55
  56 /* description of active local variable */
  57 typedef struct Vardesc {
  58     short idx;  /* variable index in stack */
  59 } Vardesc;
  60
  61
  62 /* description of pending goto statements and label statements */
  63 typedef struct Labeldesc {
  64     TString *name;  /* label identifier */
  65     int pc;  /* position in code */
  66     int line;  /* line where it appeared */
  67     lu_byte nactvar;  /* local level where it appears in current block */
  68 } Labeldesc;
  69
  70
  71 /* list of labels or gotos */
  72 typedef struct Labellist {
  73     Labeldesc *arr;  /* array */
  74     int n;  /* number of entries in use */
  75     int size;  /* array size */
  76 } Labellist;
  77
  78
  79 /* dynamic structures used by the parser */
  80 typedef struct Dyndata {
  81     struct {  /* list of active local variables */
  82         Vardesc *arr;
  83         int n;
  84         int size;
  85     } actvar;
  86     Labellist gt;  /* list of pending gotos */
  87     Labellist label;   /* list of active labels */
  88 } Dyndata;
  89
  90
  91 /* control of blocks */
  92 struct BlockCnt;  /* defined in lparser.c */
  93
  94
  95 /* state needed to generate code for a given function */
  96 typedef struct FuncState {
  97     Proto *f;  /* current function header */
  98     Table *h;  /* table to find (and reuse) elements in `k' */
  99     struct FuncState *prev;  /* enclosing function */
 100     struct LexState *ls;  /* lexical state */
 101     struct BlockCnt *bl;  /* chain of current blocks */
 102     int pc;  /* next position to code (equivalent to `ncode') */
 103     int lasttarget;   /* 'label' of last 'jump label' */
 104     int jpc;  /* list of pending jumps to `pc' */
 105     int nk;  /* number of elements in `k' */
 106     int np;  /* number of elements in `p' */
 107     int firstlocal;  /* index of first local var (in Dyndata array) */
 108     short nlocvars;  /* number of elements in 'f->locvars' */
 109     lu_byte nactvar;  /* number of active local variables */
 110     lu_byte nups;  /* number of upvalues */
 111     lu_byte freereg;  /* first free register */
 112 } FuncState;
 113
 114
 115 LUAI_FUNC Closure *luaY_parser(lua_State *L, ZIO *z, Mbuffer *buff,
 116                                Dyndata *dyd, const char *name, int firstchar);
 117
 118
 119 #endif