diff -r 4cad87e11bf6 -r 0a24853de796 misc/liblua/lparser.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/liblua/lparser.c	Mon Feb 15 19:49:20 2010 +0000
@@ -0,0 +1,1339 @@
+/*
+** $Id: lparser.c,v 2.42.1.3 2007/12/28 15:32:23 roberto Exp $
+** 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, MAX_INT, "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);
+    luaY_checklimit(ls->fs, nvars, LUAI_MAXCCALLS - ls->L->nCcalls,
+                    "variables in assignment");
+    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);
+}
+
+/* }====================================================================== */