external/mit/lua/dist/src/lparser.h

   1 /*      $NetBSD: lparser.h,v 1.3 2015/02/02 14:03:05 lneto Exp $        */
   2
   3 /*
   4 ** Id: lparser.h,v 1.74 2014/10/25 11:50:46 roberto Exp
   5 ** Lua Parser
   6 ** See Copyright Notice in lua.h
   7 */
   8
   9 #ifndef lparser_h
  10 #define lparser_h
  11
  12 #include "llimits.h"
  13 #include "lobject.h"
  14 #include "lzio.h"
  15
  16
  17 /*
  18 ** Expression descriptor
  19 */
  20
  21 typedef enum {
  22   VVOID,        /* no value */
  23   VNIL,
  24   VTRUE,
  25   VFALSE,
  26   VK,           /* info = index of constant in 'k' */
  27 #ifndef _KERNEL
  28   VKFLT,        /* nval = numerical float value */
  29 #endif
  30   VKINT,        /* nval = numerical integer value */
  31   VNONRELOC,    /* info = result register */
  32   VLOCAL,       /* info = local register */
  33   VUPVAL,       /* info = index of upvalue in 'upvalues' */
  34   VINDEXED,     /* t = table register/upvalue; idx = index R/K */
  35   VJMP,         /* info = instruction pc */
  36   VRELOCABLE,   /* info = instruction pc */
  37   VCALL,        /* info = instruction pc */
  38   VVARARG       /* info = instruction pc */
  39 } expkind;
  40
  41
  42 #define vkisvar(k)      (VLOCAL <= (k) && (k) <= VINDEXED)
  43 #define vkisinreg(k)    ((k) == VNONRELOC || (k) == VLOCAL)
  44
  45 typedef struct expdesc {
  46   expkind k;
  47   union {
  48     struct {  /* for indexed variables (VINDEXED) */
  49       short idx;  /* index (R/K) */
  50       lu_byte t;  /* table (register or upvalue) */
  51       lu_byte vt;  /* whether 't' is register (VLOCAL) or upvalue (VUPVAL) */
  52     } ind;
  53     int info;  /* for generic use */
  54 #ifndef _KERNEL
  55     lua_Number nval;  /* for VKFLT */
  56 #endif
  57     lua_Integer ival;    /* for VKINT */
  58   } u;
  59   int t;  /* patch list of 'exit when true' */
  60   int f;  /* patch list of 'exit when false' */
  61 } expdesc;
  62
  63
  64 /* description of active local variable */
  65 typedef struct Vardesc {
  66   short idx;  /* variable index in stack */
  67 } Vardesc;
  68
  69
  70 /* description of pending goto statements and label statements */
  71 typedef struct Labeldesc {
  72   TString *name;  /* label identifier */
  73   int pc;  /* position in code */
  74   int line;  /* line where it appeared */
  75   lu_byte nactvar;  /* local level where it appears in current block */
  76 } Labeldesc;
  77
  78
  79 /* list of labels or gotos */
  80 typedef struct Labellist {
  81   Labeldesc *arr;  /* array */
  82   int n;  /* number of entries in use */
  83   int size;  /* array size */
  84 } Labellist;
  85
  86
  87 /* dynamic structures used by the parser */
  88 typedef struct Dyndata {
  89   struct {  /* list of active local variables */
  90     Vardesc *arr;
  91     int n;
  92     int size;
  93   } actvar;
  94   Labellist gt;  /* list of pending gotos */
  95   Labellist label;   /* list of active labels */
  96 } Dyndata;
  97
  98
  99 /* control of blocks */
 100 struct BlockCnt;  /* defined in lparser.c */
 101
 102
 103 /* state needed to generate code for a given function */
 104 typedef struct FuncState {
 105   Proto *f;  /* current function header */
 106   struct FuncState *prev;  /* enclosing function */
 107   struct LexState *ls;  /* lexical state */
 108   struct BlockCnt *bl;  /* chain of current blocks */
 109   int pc;  /* next position to code (equivalent to 'ncode') */
 110   int lasttarget;   /* 'label' of last 'jump label' */
 111   int jpc;  /* list of pending jumps to 'pc' */
 112   int nk;  /* number of elements in 'k' */
 113   int np;  /* number of elements in 'p' */
 114   int firstlocal;  /* index of first local var (in Dyndata array) */
 115   short nlocvars;  /* number of elements in 'f->locvars' */
 116   lu_byte nactvar;  /* number of active local variables */
 117   lu_byte nups;  /* number of upvalues */
 118   lu_byte freereg;  /* first free register */
 119 } FuncState;
 120
 121
 122 LUAI_FUNC LClosure *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff,
 123                                  Dyndata *dyd, const char *name, int firstchar);
 124
 125
 126 #endif