official branch for Lua 5.1

1 files changed, 0 insertions, 1337 deletions

diff --git a/lparser.c b/lparser.c
deleted file mode 100644
index f98eb258..00000000
--- a/lparser.c
+++ /dev/null
@@ -1,1337 +0,0 @@
-/*
-** $Id: lparser.c,v 2.41 2006/03/09 18:15:48 roberto Exp roberto $
-** Lua Parser
-** See Copyright Notice in lua.h
-*/
-
-
-#include <string.h>
-
-#define lparser_c
-#define LUA_CORE
-
-#include "lua.h"
-
-#include "lcode.h"
-#include "ldebug.h"
-#include "ldo.h"
-#include "lfunc.h"
-#include "llex.h"
-#include "lmem.h"
-#include "lobject.h"
-#include "lopcodes.h"
-#include "lparser.h"
-#include "lstate.h"
-#include "lstring.h"
-#include "ltable.h"
-
-
-
-#define hasmultret(k)           ((k) == VCALL || (k) == VVARARG)
-
-#define getlocvar(fs, i)        ((fs)->f->locvars[(fs)->actvar[i]])
-
-#define luaY_checklimit(fs,v,l,m)       if ((v)>(l)) errorlimit(fs,l,m)
-
-
-/*
-** nodes for block list (list of active blocks)
-*/
-typedef struct BlockCnt {
-  struct BlockCnt *previous;  /* chain */
-  int breaklist;  /* list of jumps out of this loop */
-  lu_byte nactvar;  /* # active locals outside the breakable structure */
-  lu_byte upval;  /* true if some variable in the block is an upvalue */
-  lu_byte isbreakable;  /* true if `block' is a loop */
-} BlockCnt;
-
-
-
-/*
-** prototypes for recursive non-terminal functions
-*/
-static void chunk (LexState *ls);
-static void expr (LexState *ls, expdesc *v);
-
-
-static void anchor_token (LexState *ls) {
-  if (ls->t.token == TK_NAME || ls->t.token == TK_STRING) {
-    TString *ts = ls->t.seminfo.ts;
-    luaX_newstring(ls, getstr(ts), ts->tsv.len);
-  }
-}
-
-
-static void error_expected (LexState *ls, int token) {
-  luaX_syntaxerror(ls,
-      luaO_pushfstring(ls->L, LUA_QS " expected", luaX_token2str(ls, token)));
-}
-
-
-static void errorlimit (FuncState *fs, int limit, const char *what) {
-  const char *msg = (fs->f->linedefined == 0) ?
-    luaO_pushfstring(fs->L, "main function has more than %d %s", limit, what) :
-    luaO_pushfstring(fs->L, "function at line %d has more than %d %s",
-                            fs->f->linedefined, limit, what);
-  luaX_lexerror(fs->ls, msg, 0);
-}
-
-
-static int testnext (LexState *ls, int c) {
-  if (ls->t.token == c) {
-    luaX_next(ls);
-    return 1;
-  }
-  else return 0;
-}
-
-
-static void check (LexState *ls, int c) {
-  if (ls->t.token != c)
-    error_expected(ls, c);
-}
-
-static void checknext (LexState *ls, int c) {
-  check(ls, c);
-  luaX_next(ls);
-}
-
-
-#define check_condition(ls,c,msg)       { if (!(c)) luaX_syntaxerror(ls, msg); }
-
-
-
-static void check_match (LexState *ls, int what, int who, int where) {
-  if (!testnext(ls, what)) {
-    if (where == ls->linenumber)
-      error_expected(ls, what);
-    else {
-      luaX_syntaxerror(ls, luaO_pushfstring(ls->L,
-             LUA_QS " expected (to close " LUA_QS " at line %d)",
-              luaX_token2str(ls, what), luaX_token2str(ls, who), where));
-    }
-  }
-}
-
-
-static TString *str_checkname (LexState *ls) {
-  TString *ts;
-  check(ls, TK_NAME);
-  ts = ls->t.seminfo.ts;
-  luaX_next(ls);
-  return ts;
-}
-
-
-static void init_exp (expdesc *e, expkind k, int i) {
-  e->f = e->t = NO_JUMP;
-  e->k = k;
-  e->u.s.info = i;
-}
-
-
-static void codestring (LexState *ls, expdesc *e, TString *s) {
-  init_exp(e, VK, luaK_stringK(ls->fs, s));
-}
-
-
-static void checkname(LexState *ls, expdesc *e) {
-  codestring(ls, e, str_checkname(ls));
-}
-
-
-static int registerlocalvar (LexState *ls, TString *varname) {
-  FuncState *fs = ls->fs;
-  Proto *f = fs->f;
-  int oldsize = f->sizelocvars;
-  luaM_growvector(ls->L, f->locvars, fs->nlocvars, f->sizelocvars,
-                  LocVar, SHRT_MAX, "too many local variables");
-  while (oldsize < f->sizelocvars) f->locvars[oldsize++].varname = NULL;
-  f->locvars[fs->nlocvars].varname = varname;
-  luaC_objbarrier(ls->L, f, varname);
-  return fs->nlocvars++;
-}
-
-
-#define new_localvarliteral(ls,v,n) \
-  new_localvar(ls, luaX_newstring(ls, "" v, (sizeof(v)/sizeof(char))-1), n)
-
-
-static void new_localvar (LexState *ls, TString *name, int n) {
-  FuncState *fs = ls->fs;
-  luaY_checklimit(fs, fs->nactvar+n+1, LUAI_MAXVARS, "local variables");
-  fs->actvar[fs->nactvar+n] = cast(unsigned short, registerlocalvar(ls, name));
-}
-
-
-static void adjustlocalvars (LexState *ls, int nvars) {
-  FuncState *fs = ls->fs;
-  fs->nactvar = cast_byte(fs->nactvar + nvars);
-  for (; nvars; nvars--) {
-    getlocvar(fs, fs->nactvar - nvars).startpc = fs->pc;
-  }
-}
-
-
-static void removevars (LexState *ls, int tolevel) {
-  FuncState *fs = ls->fs;
-  while (fs->nactvar > tolevel)
-    getlocvar(fs, --fs->nactvar).endpc = fs->pc;
-}
-
-
-static int indexupvalue (FuncState *fs, TString *name, expdesc *v) {
-  int i;
-  Proto *f = fs->f;
-  int oldsize = f->sizeupvalues;
-  for (i=0; i<f->nups; i++) {
-    if (fs->upvalues[i].k == v->k && fs->upvalues[i].info == v->u.s.info) {
-      lua_assert(f->upvalues[i] == name);
-      return i;
-    }
-  }
-  /* new one */
-  luaY_checklimit(fs, f->nups + 1, LUAI_MAXUPVALUES, "upvalues");
-  luaM_growvector(fs->L, f->upvalues, f->nups, f->sizeupvalues,
-                  TString *, MAX_INT, "");
-  while (oldsize < f->sizeupvalues) f->upvalues[oldsize++] = NULL;
-  f->upvalues[f->nups] = name;
-  luaC_objbarrier(fs->L, f, name);
-  lua_assert(v->k == VLOCAL || v->k == VUPVAL);
-  fs->upvalues[f->nups].k = cast_byte(v->k);
-  fs->upvalues[f->nups].info = cast_byte(v->u.s.info);
-  return f->nups++;
-}
-
-
-static int searchvar (FuncState *fs, TString *n) {
-  int i;
-  for (i=fs->nactvar-1; i >= 0; i--) {
-    if (n == getlocvar(fs, i).varname)
-      return i;
-  }
-  return -1;  /* not found */
-}
-
-
-static void markupval (FuncState *fs, int level) {
-  BlockCnt *bl = fs->bl;
-  while (bl && bl->nactvar > level) bl = bl->previous;
-  if (bl) bl->upval = 1;
-}
-
-
-static int singlevaraux (FuncState *fs, TString *n, expdesc *var, int base) {
-  if (fs == NULL) {  /* no more levels? */
-    init_exp(var, VGLOBAL, NO_REG);  /* default is global variable */
-    return VGLOBAL;
-  }
-  else {
-    int v = searchvar(fs, n);  /* look up at current level */
-    if (v >= 0) {
-      init_exp(var, VLOCAL, v);
-      if (!base)
-        markupval(fs, v);  /* local will be used as an upval */
-      return VLOCAL;
-    }
-    else {  /* not found at current level; try upper one */
-      if (singlevaraux(fs->prev, n, var, 0) == VGLOBAL)
-        return VGLOBAL;
-      var->u.s.info = indexupvalue(fs, n, var);  /* else was LOCAL or UPVAL */
-      var->k = VUPVAL;  /* upvalue in this level */
-      return VUPVAL;
-    }
-  }
-}
-
-
-static void singlevar (LexState *ls, expdesc *var) {
-  TString *varname = str_checkname(ls);
-  FuncState *fs = ls->fs;
-  if (singlevaraux(fs, varname, var, 1) == VGLOBAL)
-    var->u.s.info = luaK_stringK(fs, varname);  /* info points to global name */
-}
-
-
-static void adjust_assign (LexState *ls, int nvars, int nexps, expdesc *e) {
-  FuncState *fs = ls->fs;
-  int extra = nvars - nexps;
-  if (hasmultret(e->k)) {
-    extra++;  /* includes call itself */
-    if (extra < 0) extra = 0;
-    luaK_setreturns(fs, e, extra);  /* last exp. provides the difference */
-    if (extra > 1) luaK_reserveregs(fs, extra-1);
-  }
-  else {
-    if (e->k != VVOID) luaK_exp2nextreg(fs, e);  /* close last expression */
-    if (extra > 0) {
-      int reg = fs->freereg;
-      luaK_reserveregs(fs, extra);
-      luaK_nil(fs, reg, extra);
-    }
-  }
-}
-
-
-static void enterlevel (LexState *ls) {
-  if (++ls->L->nCcalls > LUAI_MAXCCALLS)
-        luaX_lexerror(ls, "chunk has too many syntax levels", 0);
-}
-
-
-#define leavelevel(ls)  ((ls)->L->nCcalls--)
-
-
-static void enterblock (FuncState *fs, BlockCnt *bl, lu_byte isbreakable) {
-  bl->breaklist = NO_JUMP;
-  bl->isbreakable = isbreakable;
-  bl->nactvar = fs->nactvar;
-  bl->upval = 0;
-  bl->previous = fs->bl;
-  fs->bl = bl;
-  lua_assert(fs->freereg == fs->nactvar);
-}
-
-
-static void leaveblock (FuncState *fs) {
-  BlockCnt *bl = fs->bl;
-  fs->bl = bl->previous;
-  removevars(fs->ls, bl->nactvar);
-  if (bl->upval)
-    luaK_codeABC(fs, OP_CLOSE, bl->nactvar, 0, 0);
-  /* a block either controls scope or breaks (never both) */
-  lua_assert(!bl->isbreakable || !bl->upval);
-  lua_assert(bl->nactvar == fs->nactvar);
-  fs->freereg = fs->nactvar;  /* free registers */
-  luaK_patchtohere(fs, bl->breaklist);
-}
-
-
-static void pushclosure (LexState *ls, FuncState *func, expdesc *v) {
-  FuncState *fs = ls->fs;
-  Proto *f = fs->f;
-  int oldsize = f->sizep;
-  int i;
-  luaM_growvector(ls->L, f->p, fs->np, f->sizep, Proto *,
-                  MAXARG_Bx, "constant table overflow");
-  while (oldsize < f->sizep) f->p[oldsize++] = NULL;
-  f->p[fs->np++] = func->f;
-  luaC_objbarrier(ls->L, f, func->f);
-  init_exp(v, VRELOCABLE, luaK_codeABx(fs, OP_CLOSURE, 0, fs->np-1));
-  for (i=0; i<func->f->nups; i++) {
-    OpCode o = (func->upvalues[i].k == VLOCAL) ? OP_MOVE : OP_GETUPVAL;
-    luaK_codeABC(fs, o, 0, func->upvalues[i].info, 0);
-  }
-}
-
-
-static void open_func (LexState *ls, FuncState *fs) {
-  lua_State *L = ls->L;
-  Proto *f = luaF_newproto(L);
-  fs->f = f;
-  fs->prev = ls->fs;  /* linked list of funcstates */
-  fs->ls = ls;
-  fs->L = L;
-  ls->fs = fs;
-  fs->pc = 0;
-  fs->lasttarget = -1;
-  fs->jpc = NO_JUMP;
-  fs->freereg = 0;
-  fs->nk = 0;
-  fs->np = 0;
-  fs->nlocvars = 0;
-  fs->nactvar = 0;
-  fs->bl = NULL;
-  f->source = ls->source;
-  f->maxstacksize = 2;  /* registers 0/1 are always valid */
-  fs->h = luaH_new(L, 0, 0);
-  /* anchor table of constants and prototype (to avoid being collected) */
-  sethvalue2s(L, L->top, fs->h);
-  incr_top(L);
-  setptvalue2s(L, L->top, f);
-  incr_top(L);
-}
-
-
-static void close_func (LexState *ls) {
-  lua_State *L = ls->L;
-  FuncState *fs = ls->fs;
-  Proto *f = fs->f;
-  removevars(ls, 0);
-  luaK_ret(fs, 0, 0);  /* final return */
-  luaM_reallocvector(L, f->code, f->sizecode, fs->pc, Instruction);
-  f->sizecode = fs->pc;
-  luaM_reallocvector(L, f->lineinfo, f->sizelineinfo, fs->pc, int);
-  f->sizelineinfo = fs->pc;
-  luaM_reallocvector(L, f->k, f->sizek, fs->nk, TValue);
-  f->sizek = fs->nk;
-  luaM_reallocvector(L, f->p, f->sizep, fs->np, Proto *);
-  f->sizep = fs->np;
-  luaM_reallocvector(L, f->locvars, f->sizelocvars, fs->nlocvars, LocVar);
-  f->sizelocvars = fs->nlocvars;
-  luaM_reallocvector(L, f->upvalues, f->sizeupvalues, f->nups, TString *);
-  f->sizeupvalues = f->nups;
-  lua_assert(luaG_checkcode(f));
-  lua_assert(fs->bl == NULL);
-  ls->fs = fs->prev;
-  L->top -= 2;  /* remove table and prototype from the stack */
-  /* last token read was anchored in defunct function; must reanchor it */
-  if (fs) anchor_token(ls);
-}
-
-
-Proto *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff, const char *name) {
-  struct LexState lexstate;
-  struct FuncState funcstate;
-  lexstate.buff = buff;
-  luaX_setinput(L, &lexstate, z, luaS_new(L, name));
-  open_func(&lexstate, &funcstate);
-  funcstate.f->is_vararg = VARARG_ISVARARG;  /* main func. is always vararg */
-  luaX_next(&lexstate);  /* read first token */
-  chunk(&lexstate);
-  check(&lexstate, TK_EOS);
-  close_func(&lexstate);
-  lua_assert(funcstate.prev == NULL);
-  lua_assert(funcstate.f->nups == 0);
-  lua_assert(lexstate.fs == NULL);
-  return funcstate.f;
-}
-
-
-
-/*============================================================*/
-/* GRAMMAR RULES */
-/*============================================================*/
-
-
-static void field (LexState *ls, expdesc *v) {
-  /* field -> ['.' | ':'] NAME */
-  FuncState *fs = ls->fs;
-  expdesc key;
-  luaK_exp2anyreg(fs, v);
-  luaX_next(ls);  /* skip the dot or colon */
-  checkname(ls, &key);
-  luaK_indexed(fs, v, &key);
-}
-
-
-static void yindex (LexState *ls, expdesc *v) {
-  /* index -> '[' expr ']' */
-  luaX_next(ls);  /* skip the '[' */
-  expr(ls, v);
-  luaK_exp2val(ls->fs, v);
-  checknext(ls, ']');
-}
-
-
-/*
-** {======================================================================
-** Rules for Constructors
-** =======================================================================
-*/
-
-
-struct ConsControl {
-  expdesc v;  /* last list item read */
-  expdesc *t;  /* table descriptor */
-  int nh;  /* total number of `record' elements */
-  int na;  /* total number of array elements */
-  int tostore;  /* number of array elements pending to be stored */
-};
-
-
-static void recfield (LexState *ls, struct ConsControl *cc) {
-  /* recfield -> (NAME | `['exp1`]') = exp1 */
-  FuncState *fs = ls->fs;
-  int reg = ls->fs->freereg;
-  expdesc key, val;
-  int rkkey;
-  if (ls->t.token == TK_NAME) {
-    luaY_checklimit(fs, cc->nh, MAX_INT, "items in a constructor");
-    checkname(ls, &key);
-  }
-  else  /* ls->t.token == '[' */
-    yindex(ls, &key);
-  cc->nh++;
-  checknext(ls, '=');
-  rkkey = luaK_exp2RK(fs, &key);
-  expr(ls, &val);
-  luaK_codeABC(fs, OP_SETTABLE, cc->t->u.s.info, rkkey, luaK_exp2RK(fs, &val));
-  fs->freereg = reg;  /* free registers */
-}
-
-
-static void closelistfield (FuncState *fs, struct ConsControl *cc) {
-  if (cc->v.k == VVOID) return;  /* there is no list item */
-  luaK_exp2nextreg(fs, &cc->v);
-  cc->v.k = VVOID;
-  if (cc->tostore == LFIELDS_PER_FLUSH) {
-    luaK_setlist(fs, cc->t->u.s.info, cc->na, cc->tostore);  /* flush */
-    cc->tostore = 0;  /* no more items pending */
-  }
-}
-
-
-static void lastlistfield (FuncState *fs, struct ConsControl *cc) {
-  if (cc->tostore == 0) return;
-  if (hasmultret(cc->v.k)) {
-    luaK_setmultret(fs, &cc->v);
-    luaK_setlist(fs, cc->t->u.s.info, cc->na, LUA_MULTRET);
-    cc->na--;  /* do not count last expression (unknown number of elements) */
-  }
-  else {
-    if (cc->v.k != VVOID)
-      luaK_exp2nextreg(fs, &cc->v);
-    luaK_setlist(fs, cc->t->u.s.info, cc->na, cc->tostore);
-  }
-}
-
-
-static void listfield (LexState *ls, struct ConsControl *cc) {
-  expr(ls, &cc->v);
-  luaY_checklimit(ls->fs, cc->na, MAXARG_Bx, "items in a constructor");
-  cc->na++;
-  cc->tostore++;
-}
-
-
-static void constructor (LexState *ls, expdesc *t) {
-  /* constructor -> ?? */
-  FuncState *fs = ls->fs;
-  int line = ls->linenumber;
-  int pc = luaK_codeABC(fs, OP_NEWTABLE, 0, 0, 0);
-  struct ConsControl cc;
-  cc.na = cc.nh = cc.tostore = 0;
-  cc.t = t;
-  init_exp(t, VRELOCABLE, pc);
-  init_exp(&cc.v, VVOID, 0);  /* no value (yet) */
-  luaK_exp2nextreg(ls->fs, t);  /* fix it at stack top (for gc) */
-  checknext(ls, '{');
-  do {
-    lua_assert(cc.v.k == VVOID || cc.tostore > 0);
-    if (ls->t.token == '}') break;
-    closelistfield(fs, &cc);
-    switch(ls->t.token) {
-      case TK_NAME: {  /* may be listfields or recfields */
-        luaX_lookahead(ls);
-        if (ls->lookahead.token != '=')  /* expression? */
-          listfield(ls, &cc);
-        else
-          recfield(ls, &cc);
-        break;
-      }
-      case '[': {  /* constructor_item -> recfield */
-        recfield(ls, &cc);
-        break;
-      }
-      default: {  /* constructor_part -> listfield */
-        listfield(ls, &cc);
-        break;
-      }
-    }
-  } while (testnext(ls, ',') || testnext(ls, ';'));
-  check_match(ls, '}', '{', line);
-  lastlistfield(fs, &cc);
-  SETARG_B(fs->f->code[pc], luaO_int2fb(cc.na)); /* set initial array size */
-  SETARG_C(fs->f->code[pc], luaO_int2fb(cc.nh));  /* set initial table size */
-}
-
-/* }====================================================================== */
-
-
-
-static void parlist (LexState *ls) {
-  /* parlist -> [ param { `,' param } ] */
-  FuncState *fs = ls->fs;
-  Proto *f = fs->f;
-  int nparams = 0;
-  f->is_vararg = 0;
-  if (ls->t.token != ')') {  /* is `parlist' not empty? */
-    do {
-      switch (ls->t.token) {
-        case TK_NAME: {  /* param -> NAME */
-          new_localvar(ls, str_checkname(ls), nparams++);
-          break;
-        }
-        case TK_DOTS: {  /* param -> `...' */
-          luaX_next(ls);
-#if defined(LUA_COMPAT_VARARG)
-          /* use `arg' as default name */
-          new_localvarliteral(ls, "arg", nparams++);
-          f->is_vararg = VARARG_HASARG | VARARG_NEEDSARG;
-#endif
-          f->is_vararg |= VARARG_ISVARARG;
-          break;
-        }
-        default: luaX_syntaxerror(ls, "<name> or " LUA_QL("...") " expected");
-      }
-    } while (!f->is_vararg && testnext(ls, ','));
-  }
-  adjustlocalvars(ls, nparams);
-  f->numparams = cast_byte(fs->nactvar - (f->is_vararg & VARARG_HASARG));
-  luaK_reserveregs(fs, fs->nactvar);  /* reserve register for parameters */
-}
-
-
-static void body (LexState *ls, expdesc *e, int needself, int line) {
-  /* body ->  `(' parlist `)' chunk END */
-  FuncState new_fs;
-  open_func(ls, &new_fs);
-  new_fs.f->linedefined = line;
-  checknext(ls, '(');
-  if (needself) {
-    new_localvarliteral(ls, "self", 0);
-    adjustlocalvars(ls, 1);
-  }
-  parlist(ls);
-  checknext(ls, ')');
-  chunk(ls);
-  new_fs.f->lastlinedefined = ls->linenumber;
-  check_match(ls, TK_END, TK_FUNCTION, line);
-  close_func(ls);
-  pushclosure(ls, &new_fs, e);
-}
-
-
-static int explist1 (LexState *ls, expdesc *v) {
-  /* explist1 -> expr { `,' expr } */
-  int n = 1;  /* at least one expression */
-  expr(ls, v);
-  while (testnext(ls, ',')) {
-    luaK_exp2nextreg(ls->fs, v);
-    expr(ls, v);
-    n++;
-  }
-  return n;
-}
-
-
-static void funcargs (LexState *ls, expdesc *f) {
-  FuncState *fs = ls->fs;
-  expdesc args;
-  int base, nparams;
-  int line = ls->linenumber;
-  switch (ls->t.token) {
-    case '(': {  /* funcargs -> `(' [ explist1 ] `)' */
-      if (line != ls->lastline)
-        luaX_syntaxerror(ls,"ambiguous syntax (function call x new statement)");
-      luaX_next(ls);
-      if (ls->t.token == ')')  /* arg list is empty? */
-        args.k = VVOID;
-      else {
-        explist1(ls, &args);
-        luaK_setmultret(fs, &args);
-      }
-      check_match(ls, ')', '(', line);
-      break;
-    }
-    case '{': {  /* funcargs -> constructor */
-      constructor(ls, &args);
-      break;
-    }
-    case TK_STRING: {  /* funcargs -> STRING */
-      codestring(ls, &args, ls->t.seminfo.ts);
-      luaX_next(ls);  /* must use `seminfo' before `next' */
-      break;
-    }
-    default: {
-      luaX_syntaxerror(ls, "function arguments expected");
-      return;
-    }
-  }
-  lua_assert(f->k == VNONRELOC);
-  base = f->u.s.info;  /* base register for call */
-  if (hasmultret(args.k))
-    nparams = LUA_MULTRET;  /* open call */
-  else {
-    if (args.k != VVOID)
-      luaK_exp2nextreg(fs, &args);  /* close last argument */
-    nparams = fs->freereg - (base+1);
-  }
-  init_exp(f, VCALL, luaK_codeABC(fs, OP_CALL, base, nparams+1, 2));
-  luaK_fixline(fs, line);
-  fs->freereg = base+1;  /* call remove function and arguments and leaves
-                            (unless changed) one result */
-}
-
-
-
-
-/*
-** {======================================================================
-** Expression parsing
-** =======================================================================
-*/
-
-
-static void prefixexp (LexState *ls, expdesc *v) {
-  /* prefixexp -> NAME | '(' expr ')' */
-  switch (ls->t.token) {
-    case '(': {
-      int line = ls->linenumber;
-      luaX_next(ls);
-      expr(ls, v);
-      check_match(ls, ')', '(', line);
-      luaK_dischargevars(ls->fs, v);
-      return;
-    }
-    case TK_NAME: {
-      singlevar(ls, v);
-      return;
-    }
-    default: {
-      luaX_syntaxerror(ls, "unexpected symbol");
-      return;
-    }
-  }
-}
-
-
-static void primaryexp (LexState *ls, expdesc *v) {
-  /* primaryexp ->
-        prefixexp { `.' NAME | `[' exp `]' | `:' NAME funcargs | funcargs } */
-  FuncState *fs = ls->fs;
-  prefixexp(ls, v);
-  for (;;) {
-    switch (ls->t.token) {
-      case '.': {  /* field */
-        field(ls, v);
-        break;
-      }
-      case '[': {  /* `[' exp1 `]' */
-        expdesc key;
-        luaK_exp2anyreg(fs, v);
-        yindex(ls, &key);
-        luaK_indexed(fs, v, &key);
-        break;
-      }
-      case ':': {  /* `:' NAME funcargs */
-        expdesc key;
-        luaX_next(ls);
-        checkname(ls, &key);
-        luaK_self(fs, v, &key);
-        funcargs(ls, v);
-        break;
-      }
-      case '(': case TK_STRING: case '{': {  /* funcargs */
-        luaK_exp2nextreg(fs, v);
-        funcargs(ls, v);
-        break;
-      }
-      default: return;
-    }
-  }
-}
-
-
-static void simpleexp (LexState *ls, expdesc *v) {
-  /* simpleexp -> NUMBER | STRING | NIL | true | false | ... |
-                  constructor | FUNCTION body | primaryexp */
-  switch (ls->t.token) {
-    case TK_NUMBER: {
-      init_exp(v, VKNUM, 0);
-      v->u.nval = ls->t.seminfo.r;
-      break;
-    }
-    case TK_STRING: {
-      codestring(ls, v, ls->t.seminfo.ts);
-      break;
-    }
-    case TK_NIL: {
-      init_exp(v, VNIL, 0);
-      break;
-    }
-    case TK_TRUE: {
-      init_exp(v, VTRUE, 0);
-      break;
-    }
-    case TK_FALSE: {
-      init_exp(v, VFALSE, 0);
-      break;
-    }
-    case TK_DOTS: {  /* vararg */
-      FuncState *fs = ls->fs;
-      check_condition(ls, fs->f->is_vararg,
-                      "cannot use " LUA_QL("...") " outside a vararg function");
-      fs->f->is_vararg &= ~VARARG_NEEDSARG;  /* don't need 'arg' */
-      init_exp(v, VVARARG, luaK_codeABC(fs, OP_VARARG, 0, 1, 0));
-      break;
-    }
-    case '{': {  /* constructor */
-      constructor(ls, v);
-      return;
-    }
-    case TK_FUNCTION: {
-      luaX_next(ls);
-      body(ls, v, 0, ls->linenumber);
-      return;
-    }
-    default: {
-      primaryexp(ls, v);
-      return;
-    }
-  }
-  luaX_next(ls);
-}
-
-
-static UnOpr getunopr (int op) {
-  switch (op) {
-    case TK_NOT: return OPR_NOT;
-    case '-': return OPR_MINUS;
-    case '#': return OPR_LEN;
-    default: return OPR_NOUNOPR;
-  }
-}
-
-
-static BinOpr getbinopr (int op) {
-  switch (op) {
-    case '+': return OPR_ADD;
-    case '-': return OPR_SUB;
-    case '*': return OPR_MUL;
-    case '/': return OPR_DIV;
-    case '%': return OPR_MOD;
-    case '^': return OPR_POW;
-    case TK_CONCAT: return OPR_CONCAT;
-    case TK_NE: return OPR_NE;
-    case TK_EQ: return OPR_EQ;
-    case '<': return OPR_LT;
-    case TK_LE: return OPR_LE;
-    case '>': return OPR_GT;
-    case TK_GE: return OPR_GE;
-    case TK_AND: return OPR_AND;
-    case TK_OR: return OPR_OR;
-    default: return OPR_NOBINOPR;
-  }
-}
-
-
-static const struct {
-  lu_byte left;  /* left priority for each binary operator */
-  lu_byte right; /* right priority */
-} priority[] = {  /* ORDER OPR */
-   {6, 6}, {6, 6}, {7, 7}, {7, 7}, {7, 7},  /* `+' `-' `/' `%' */
-   {10, 9}, {5, 4},                 /* power and concat (right associative) */
-   {3, 3}, {3, 3},                  /* equality and inequality */
-   {3, 3}, {3, 3}, {3, 3}, {3, 3},  /* order */
-   {2, 2}, {1, 1}                   /* logical (and/or) */
-};
-
-#define UNARY_PRIORITY  8  /* priority for unary operators */
-
-
-/*
-** subexpr -> (simpleexp | unop subexpr) { binop subexpr }
-** where `binop' is any binary operator with a priority higher than `limit'
-*/
-static BinOpr subexpr (LexState *ls, expdesc *v, unsigned int limit) {
-  BinOpr op;
-  UnOpr uop;
-  enterlevel(ls);
-  uop = getunopr(ls->t.token);
-  if (uop != OPR_NOUNOPR) {
-    luaX_next(ls);
-    subexpr(ls, v, UNARY_PRIORITY);
-    luaK_prefix(ls->fs, uop, v);
-  }
-  else simpleexp(ls, v);
-  /* expand while operators have priorities higher than `limit' */
-  op = getbinopr(ls->t.token);
-  while (op != OPR_NOBINOPR && priority[op].left > limit) {
-    expdesc v2;
-    BinOpr nextop;
-    luaX_next(ls);
-    luaK_infix(ls->fs, op, v);
-    /* read sub-expression with higher priority */
-    nextop = subexpr(ls, &v2, priority[op].right);
-    luaK_posfix(ls->fs, op, v, &v2);
-    op = nextop;
-  }
-  leavelevel(ls);
-  return op;  /* return first untreated operator */
-}
-
-
-static void expr (LexState *ls, expdesc *v) {
-  subexpr(ls, v, 0);
-}
-
-/* }==================================================================== */
-
-
-
-/*
-** {======================================================================
-** Rules for Statements
-** =======================================================================
-*/
-
-
-static int block_follow (int token) {
-  switch (token) {
-    case TK_ELSE: case TK_ELSEIF: case TK_END:
-    case TK_UNTIL: case TK_EOS:
-      return 1;
-    default: return 0;
-  }
-}
-
-
-static void block (LexState *ls) {
-  /* block -> chunk */
-  FuncState *fs = ls->fs;
-  BlockCnt bl;
-  enterblock(fs, &bl, 0);
-  chunk(ls);
-  lua_assert(bl.breaklist == NO_JUMP);
-  leaveblock(fs);
-}
-
-
-/*
-** structure to chain all variables in the left-hand side of an
-** assignment
-*/
-struct LHS_assign {
-  struct LHS_assign *prev;
-  expdesc v;  /* variable (global, local, upvalue, or indexed) */
-};
-
-
-/*
-** check whether, in an assignment to a local variable, the local variable
-** is needed in a previous assignment (to a table). If so, save original
-** local value in a safe place and use this safe copy in the previous
-** assignment.
-*/
-static void check_conflict (LexState *ls, struct LHS_assign *lh, expdesc *v) {
-  FuncState *fs = ls->fs;
-  int extra = fs->freereg;  /* eventual position to save local variable */
-  int conflict = 0;
-  for (; lh; lh = lh->prev) {
-    if (lh->v.k == VINDEXED) {
-      if (lh->v.u.s.info == v->u.s.info) {  /* conflict? */
-        conflict = 1;
-        lh->v.u.s.info = extra;  /* previous assignment will use safe copy */
-      }
-      if (lh->v.u.s.aux == v->u.s.info) {  /* conflict? */
-        conflict = 1;
-        lh->v.u.s.aux = extra;  /* previous assignment will use safe copy */
-      }
-    }
-  }
-  if (conflict) {
-    luaK_codeABC(fs, OP_MOVE, fs->freereg, v->u.s.info, 0);  /* make copy */
-    luaK_reserveregs(fs, 1);
-  }
-}
-
-
-static void assignment (LexState *ls, struct LHS_assign *lh, int nvars) {
-  expdesc e;
-  check_condition(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED,
-                      "syntax error");
-  if (testnext(ls, ',')) {  /* assignment -> `,' primaryexp assignment */
-    struct LHS_assign nv;
-    nv.prev = lh;
-    primaryexp(ls, &nv.v);
-    if (nv.v.k == VLOCAL)
-      check_conflict(ls, lh, &nv.v);
-    assignment(ls, &nv, nvars+1);
-  }
-  else {  /* assignment -> `=' explist1 */
-    int nexps;
-    checknext(ls, '=');
-    nexps = explist1(ls, &e);
-    if (nexps != nvars) {
-      adjust_assign(ls, nvars, nexps, &e);
-      if (nexps > nvars)
-        ls->fs->freereg -= nexps - nvars;  /* remove extra values */
-    }
-    else {
-      luaK_setoneret(ls->fs, &e);  /* close last expression */
-      luaK_storevar(ls->fs, &lh->v, &e);
-      return;  /* avoid default */
-    }
-  }
-  init_exp(&e, VNONRELOC, ls->fs->freereg-1);  /* default assignment */
-  luaK_storevar(ls->fs, &lh->v, &e);
-}
-
-
-static int cond (LexState *ls) {
-  /* cond -> exp */
-  expdesc v;
-  expr(ls, &v);  /* read condition */
-  if (v.k == VNIL) v.k = VFALSE;  /* `falses' are all equal here */
-  luaK_goiftrue(ls->fs, &v);
-  return v.f;
-}
-
-
-static void breakstat (LexState *ls) {
-  FuncState *fs = ls->fs;
-  BlockCnt *bl = fs->bl;
-  int upval = 0;
-  while (bl && !bl->isbreakable) {
-    upval |= bl->upval;
-    bl = bl->previous;
-  }
-  if (!bl)
-    luaX_syntaxerror(ls, "no loop to break");
-  if (upval)
-    luaK_codeABC(fs, OP_CLOSE, bl->nactvar, 0, 0);
-  luaK_concat(fs, &bl->breaklist, luaK_jump(fs));
-}
-
-
-static void whilestat (LexState *ls, int line) {
-  /* whilestat -> WHILE cond DO block END */
-  FuncState *fs = ls->fs;
-  int whileinit;
-  int condexit;
-  BlockCnt bl;
-  luaX_next(ls);  /* skip WHILE */
-  whileinit = luaK_getlabel(fs);
-  condexit = cond(ls);
-  enterblock(fs, &bl, 1);
-  checknext(ls, TK_DO);
-  block(ls);
-  luaK_patchlist(fs, luaK_jump(fs), whileinit);
-  check_match(ls, TK_END, TK_WHILE, line);
-  leaveblock(fs);
-  luaK_patchtohere(fs, condexit);  /* false conditions finish the loop */
-}
-
-
-static void repeatstat (LexState *ls, int line) {
-  /* repeatstat -> REPEAT block UNTIL cond */
-  int condexit;
-  FuncState *fs = ls->fs;
-  int repeat_init = luaK_getlabel(fs);
-  BlockCnt bl1, bl2;
-  enterblock(fs, &bl1, 1);  /* loop block */
-  enterblock(fs, &bl2, 0);  /* scope block */
-  luaX_next(ls);  /* skip REPEAT */
-  chunk(ls);
-  check_match(ls, TK_UNTIL, TK_REPEAT, line);
-  condexit = cond(ls);  /* read condition (inside scope block) */
-  if (!bl2.upval) {  /* no upvalues? */
-    leaveblock(fs);  /* finish scope */
-    luaK_patchlist(ls->fs, condexit, repeat_init);  /* close the loop */
-  }
-  else {  /* complete semantics when there are upvalues */
-    breakstat(ls);  /* if condition then break */
-    luaK_patchtohere(ls->fs, condexit);  /* else... */
-    leaveblock(fs);  /* finish scope... */
-    luaK_patchlist(ls->fs, luaK_jump(fs), repeat_init);  /* and repeat */
-  }
-  leaveblock(fs);  /* finish loop */
-}
-
-
-static int exp1 (LexState *ls) {
-  expdesc e;
-  int k;
-  expr(ls, &e);
-  k = e.k;
-  luaK_exp2nextreg(ls->fs, &e);
-  return k;
-}
-
-
-static void forbody (LexState *ls, int base, int line, int nvars, int isnum) {
-  /* forbody -> DO block */
-  BlockCnt bl;
-  FuncState *fs = ls->fs;
-  int prep, endfor;
-  adjustlocalvars(ls, 3);  /* control variables */
-  checknext(ls, TK_DO);
-  prep = isnum ? luaK_codeAsBx(fs, OP_FORPREP, base, NO_JUMP) : luaK_jump(fs);
-  enterblock(fs, &bl, 0);  /* scope for declared variables */
-  adjustlocalvars(ls, nvars);
-  luaK_reserveregs(fs, nvars);
-  block(ls);
-  leaveblock(fs);  /* end of scope for declared variables */
-  luaK_patchtohere(fs, prep);
-  endfor = (isnum) ? luaK_codeAsBx(fs, OP_FORLOOP, base, NO_JUMP) :
-                     luaK_codeABC(fs, OP_TFORLOOP, base, 0, nvars);
-  luaK_fixline(fs, line);  /* pretend that `OP_FOR' starts the loop */
-  luaK_patchlist(fs, (isnum ? endfor : luaK_jump(fs)), prep + 1);
-}
-
-
-static void fornum (LexState *ls, TString *varname, int line) {
-  /* fornum -> NAME = exp1,exp1[,exp1] forbody */
-  FuncState *fs = ls->fs;
-  int base = fs->freereg;
-  new_localvarliteral(ls, "(for index)", 0);
-  new_localvarliteral(ls, "(for limit)", 1);
-  new_localvarliteral(ls, "(for step)", 2);
-  new_localvar(ls, varname, 3);
-  checknext(ls, '=');
-  exp1(ls);  /* initial value */
-  checknext(ls, ',');
-  exp1(ls);  /* limit */
-  if (testnext(ls, ','))
-    exp1(ls);  /* optional step */
-  else {  /* default step = 1 */
-    luaK_codeABx(fs, OP_LOADK, fs->freereg, luaK_numberK(fs, 1));
-    luaK_reserveregs(fs, 1);
-  }
-  forbody(ls, base, line, 1, 1);
-}
-
-
-static void forlist (LexState *ls, TString *indexname) {
-  /* forlist -> NAME {,NAME} IN explist1 forbody */
-  FuncState *fs = ls->fs;
-  expdesc e;
-  int nvars = 0;
-  int line;
-  int base = fs->freereg;
-  /* create control variables */
-  new_localvarliteral(ls, "(for generator)", nvars++);
-  new_localvarliteral(ls, "(for state)", nvars++);
-  new_localvarliteral(ls, "(for control)", nvars++);
-  /* create declared variables */
-  new_localvar(ls, indexname, nvars++);
-  while (testnext(ls, ','))
-    new_localvar(ls, str_checkname(ls), nvars++);
-  checknext(ls, TK_IN);
-  line = ls->linenumber;
-  adjust_assign(ls, 3, explist1(ls, &e), &e);
-  luaK_checkstack(fs, 3);  /* extra space to call generator */
-  forbody(ls, base, line, nvars - 3, 0);
-}
-
-
-static void forstat (LexState *ls, int line) {
-  /* forstat -> FOR (fornum | forlist) END */
-  FuncState *fs = ls->fs;
-  TString *varname;
-  BlockCnt bl;
-  enterblock(fs, &bl, 1);  /* scope for loop and control variables */
-  luaX_next(ls);  /* skip `for' */
-  varname = str_checkname(ls);  /* first variable name */
-  switch (ls->t.token) {
-    case '=': fornum(ls, varname, line); break;
-    case ',': case TK_IN: forlist(ls, varname); break;
-    default: luaX_syntaxerror(ls, LUA_QL("=") " or " LUA_QL("in") " expected");
-  }
-  check_match(ls, TK_END, TK_FOR, line);
-  leaveblock(fs);  /* loop scope (`break' jumps to this point) */
-}
-
-
-static int test_then_block (LexState *ls) {
-  /* test_then_block -> [IF | ELSEIF] cond THEN block */
-  int condexit;
-  luaX_next(ls);  /* skip IF or ELSEIF */
-  condexit = cond(ls);
-  checknext(ls, TK_THEN);
-  block(ls);  /* `then' part */
-  return condexit;
-}
-
-
-static void ifstat (LexState *ls, int line) {
-  /* ifstat -> IF cond THEN block {ELSEIF cond THEN block} [ELSE block] END */
-  FuncState *fs = ls->fs;
-  int flist;
-  int escapelist = NO_JUMP;
-  flist = test_then_block(ls);  /* IF cond THEN block */
-  while (ls->t.token == TK_ELSEIF) {
-    luaK_concat(fs, &escapelist, luaK_jump(fs));
-    luaK_patchtohere(fs, flist);
-    flist = test_then_block(ls);  /* ELSEIF cond THEN block */
-  }
-  if (ls->t.token == TK_ELSE) {
-    luaK_concat(fs, &escapelist, luaK_jump(fs));
-    luaK_patchtohere(fs, flist);
-    luaX_next(ls);  /* skip ELSE (after patch, for correct line info) */
-    block(ls);  /* `else' part */
-  }
-  else
-    luaK_concat(fs, &escapelist, flist);
-  luaK_patchtohere(fs, escapelist);
-  check_match(ls, TK_END, TK_IF, line);
-}
-
-
-static void localfunc (LexState *ls) {
-  expdesc v, b;
-  FuncState *fs = ls->fs;
-  new_localvar(ls, str_checkname(ls), 0);
-  init_exp(&v, VLOCAL, fs->freereg);
-  luaK_reserveregs(fs, 1);
-  adjustlocalvars(ls, 1);
-  body(ls, &b, 0, ls->linenumber);
-  luaK_storevar(fs, &v, &b);
-  /* debug information will only see the variable after this point! */
-  getlocvar(fs, fs->nactvar - 1).startpc = fs->pc;
-}
-
-
-static void localstat (LexState *ls) {
-  /* stat -> LOCAL NAME {`,' NAME} [`=' explist1] */
-  int nvars = 0;
-  int nexps;
-  expdesc e;
-  do {
-    new_localvar(ls, str_checkname(ls), nvars++);
-  } while (testnext(ls, ','));
-  if (testnext(ls, '='))
-    nexps = explist1(ls, &e);
-  else {
-    e.k = VVOID;
-    nexps = 0;
-  }
-  adjust_assign(ls, nvars, nexps, &e);
-  adjustlocalvars(ls, nvars);
-}
-
-
-static int funcname (LexState *ls, expdesc *v) {
-  /* funcname -> NAME {field} [`:' NAME] */
-  int needself = 0;
-  singlevar(ls, v);
-  while (ls->t.token == '.')
-    field(ls, v);
-  if (ls->t.token == ':') {
-    needself = 1;
-    field(ls, v);
-  }
-  return needself;
-}
-
-
-static void funcstat (LexState *ls, int line) {
-  /* funcstat -> FUNCTION funcname body */
-  int needself;
-  expdesc v, b;
-  luaX_next(ls);  /* skip FUNCTION */
-  needself = funcname(ls, &v);
-  body(ls, &b, needself, line);
-  luaK_storevar(ls->fs, &v, &b);
-  luaK_fixline(ls->fs, line);  /* definition `happens' in the first line */
-}
-
-
-static void exprstat (LexState *ls) {
-  /* stat -> func | assignment */
-  FuncState *fs = ls->fs;
-  struct LHS_assign v;
-  primaryexp(ls, &v.v);
-  if (v.v.k == VCALL)  /* stat -> func */
-    SETARG_C(getcode(fs, &v.v), 1);  /* call statement uses no results */
-  else {  /* stat -> assignment */
-    v.prev = NULL;
-    assignment(ls, &v, 1);
-  }
-}
-
-
-static void retstat (LexState *ls) {
-  /* stat -> RETURN explist */
-  FuncState *fs = ls->fs;
-  expdesc e;
-  int first, nret;  /* registers with returned values */
-  luaX_next(ls);  /* skip RETURN */
-  if (block_follow(ls->t.token) || ls->t.token == ';')
-    first = nret = 0;  /* return no values */
-  else {
-    nret = explist1(ls, &e);  /* optional return values */
-    if (hasmultret(e.k)) {
-      luaK_setmultret(fs, &e);
-      if (e.k == VCALL && nret == 1) {  /* tail call? */
-        SET_OPCODE(getcode(fs,&e), OP_TAILCALL);
-        lua_assert(GETARG_A(getcode(fs,&e)) == fs->nactvar);
-      }
-      first = fs->nactvar;
-      nret = LUA_MULTRET;  /* return all values */
-    }
-    else {
-      if (nret == 1)  /* only one single value? */
-        first = luaK_exp2anyreg(fs, &e);
-      else {
-        luaK_exp2nextreg(fs, &e);  /* values must go to the `stack' */
-        first = fs->nactvar;  /* return all `active' values */
-        lua_assert(nret == fs->freereg - first);
-      }
-    }
-  }
-  luaK_ret(fs, first, nret);
-}
-
-
-static int statement (LexState *ls) {
-  int line = ls->linenumber;  /* may be needed for error messages */
-  switch (ls->t.token) {
-    case TK_IF: {  /* stat -> ifstat */
-      ifstat(ls, line);
-      return 0;
-    }
-    case TK_WHILE: {  /* stat -> whilestat */
-      whilestat(ls, line);
-      return 0;
-    }
-    case TK_DO: {  /* stat -> DO block END */
-      luaX_next(ls);  /* skip DO */
-      block(ls);
-      check_match(ls, TK_END, TK_DO, line);
-      return 0;
-    }
-    case TK_FOR: {  /* stat -> forstat */
-      forstat(ls, line);
-      return 0;
-    }
-    case TK_REPEAT: {  /* stat -> repeatstat */
-      repeatstat(ls, line);
-      return 0;
-    }
-    case TK_FUNCTION: {
-      funcstat(ls, line);  /* stat -> funcstat */
-      return 0;
-    }
-    case TK_LOCAL: {  /* stat -> localstat */
-      luaX_next(ls);  /* skip LOCAL */
-      if (testnext(ls, TK_FUNCTION))  /* local function? */
-        localfunc(ls);
-      else
-        localstat(ls);
-      return 0;
-    }
-    case TK_RETURN: {  /* stat -> retstat */
-      retstat(ls);
-      return 1;  /* must be last statement */
-    }
-    case TK_BREAK: {  /* stat -> breakstat */
-      luaX_next(ls);  /* skip BREAK */
-      breakstat(ls);
-      return 1;  /* must be last statement */
-    }
-    default: {
-      exprstat(ls);
-      return 0;  /* to avoid warnings */
-    }
-  }
-}
-
-
-static void chunk (LexState *ls) {
-  /* chunk -> { stat [`;'] } */
-  int islast = 0;
-  enterlevel(ls);
-  while (!islast && !block_follow(ls->t.token)) {
-    islast = statement(ls);
-    testnext(ls, ';');
-    lua_assert(ls->fs->f->maxstacksize >= ls->fs->freereg &&
-               ls->fs->freereg >= ls->fs->nactvar);
-    ls->fs->freereg = ls->fs->nactvar;  /* free registers */
-  }
-  leavelevel(ls);
-}
-
-/* }====================================================================== */