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-rw-r--r--src/lparser.c1369
1 files changed, 787 insertions, 582 deletions
diff --git a/src/lparser.c b/src/lparser.c
index 67161c86..c1323ecd 100644
--- a/src/lparser.c
+++ b/src/lparser.c
@@ -1,16 +1,18 @@
/*
-** $Id: lparser.c,v 1.117 2000/11/29 11:57:42 roberto Exp $
-** LL(1) Parser and code generator for Lua
+** $Id: lparser.c,v 1.208 2003/04/03 13:35:34 roberto Exp $
+** Lua Parser
** See Copyright Notice in lua.h
*/
-#include <stdio.h>
#include <string.h>
+#define lparser_c
+
#include "lua.h"
#include "lcode.h"
+#include "ldebug.h"
#include "lfunc.h"
#include "llex.h"
#include "lmem.h"
@@ -21,35 +23,34 @@
#include "lstring.h"
-/*
-** Constructors descriptor:
-** `n' indicates number of elements, and `k' signals whether
-** it is a list constructor (k = 0) or a record constructor (k = 1)
-** or empty (k = ';' or '}')
-*/
-typedef struct Constdesc {
- int n;
- int k;
-} Constdesc;
-typedef struct Breaklabel {
- struct Breaklabel *previous; /* chain */
- int breaklist;
- int stacklevel;
-} Breaklabel;
+#define getlocvar(fs, i) ((fs)->f->locvars[(fs)->actvar[i]])
+
+
+#define enterlevel(ls) if (++(ls)->nestlevel > LUA_MAXPARSERLEVEL) \
+ luaX_syntaxerror(ls, "too many syntax levels");
+#define leavelevel(ls) ((ls)->nestlevel--)
+/*
+** nodes for block list (list of active blocks)
+*/
+typedef struct BlockCnt {
+ struct BlockCnt *previous; /* chain */
+ int breaklist; /* list of jumps out of this loop */
+ int nactvar; /* # active local variables outside the breakable structure */
+ int upval; /* true if some variable in the block is an upvalue */
+ int isbreakable; /* true if `block' is a loop */
+} BlockCnt;
+
/*
** prototypes for recursive non-terminal functions
*/
-static void body (LexState *ls, int needself, int line);
static void chunk (LexState *ls);
-static void constructor (LexState *ls);
static void expr (LexState *ls, expdesc *v);
-static void exp1 (LexState *ls);
@@ -65,32 +66,18 @@ static void next (LexState *ls) {
static void lookahead (LexState *ls) {
- LUA_ASSERT(ls->lookahead.token == TK_EOS, "two look-aheads");
+ lua_assert(ls->lookahead.token == TK_EOS);
ls->lookahead.token = luaX_lex(ls, &ls->lookahead.seminfo);
}
static void error_expected (LexState *ls, int token) {
- char buff[100], t[TOKEN_LEN];
- luaX_token2str(token, t);
- sprintf(buff, "`%.20s' expected", t);
- luaK_error(ls, buff);
+ luaX_syntaxerror(ls,
+ luaO_pushfstring(ls->L, "`%s' expected", luaX_token2str(ls, token)));
}
-static void check (LexState *ls, int c) {
- if (ls->t.token != c)
- error_expected(ls, c);
- next(ls);
-}
-
-
-static void check_condition (LexState *ls, int c, const char *msg) {
- if (!c) luaK_error(ls, msg);
-}
-
-
-static int optional (LexState *ls, int c) {
+static int testnext (LexState *ls, int c) {
if (ls->t.token == c) {
next(ls);
return 1;
@@ -99,40 +86,26 @@ static int optional (LexState *ls, int c) {
}
+static void check (LexState *ls, int c) {
+ if (!testnext(ls, c))
+ error_expected(ls, c);
+}
+
+
+#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 (ls->t.token != what) {
+ if (!testnext(ls, what)) {
if (where == ls->linenumber)
error_expected(ls, what);
else {
- char buff[100];
- char t_what[TOKEN_LEN], t_who[TOKEN_LEN];
- luaX_token2str(what, t_what);
- luaX_token2str(who, t_who);
- sprintf(buff, "`%.20s' expected (to close `%.20s' at line %d)",
- t_what, t_who, where);
- luaK_error(ls, buff);
+ luaX_syntaxerror(ls, luaO_pushfstring(ls->L,
+ "`%s' expected (to close `%s' at line %d)",
+ luaX_token2str(ls, what), luaX_token2str(ls, who), where));
}
}
- next(ls);
-}
-
-
-static int string_constant (FuncState *fs, TString *s) {
- Proto *f = fs->f;
- int c = s->u.s.constindex;
- if (c >= f->nkstr || f->kstr[c] != s) {
- luaM_growvector(fs->L, f->kstr, f->nkstr, 1, TString *,
- "constant table overflow", MAXARG_U);
- c = f->nkstr++;
- f->kstr[c] = s;
- s->u.s.constindex = c; /* hint for next time */
- }
- return c;
-}
-
-
-static void code_string (LexState *ls, TString *s) {
- luaK_kstr(ls, string_constant(ls->fs, s));
}
@@ -145,182 +118,224 @@ static TString *str_checkname (LexState *ls) {
}
-static int checkname (LexState *ls) {
- return string_constant(ls->fs, str_checkname(ls));
+static void init_exp (expdesc *e, expkind k, int i) {
+ e->f = e->t = NO_JUMP;
+ e->k = k;
+ e->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 luaI_registerlocalvar (LexState *ls, TString *varname) {
- Proto *f = ls->fs->f;
- luaM_growvector(ls->L, f->locvars, f->nlocvars, 1, LocVar, "", MAX_INT);
- f->locvars[f->nlocvars].varname = varname;
- return f->nlocvars++;
+ FuncState *fs = ls->fs;
+ Proto *f = fs->f;
+ luaM_growvector(ls->L, f->locvars, fs->nlocvars, f->sizelocvars,
+ LocVar, MAX_INT, "");
+ f->locvars[fs->nlocvars].varname = varname;
+ return fs->nlocvars++;
}
static void new_localvar (LexState *ls, TString *name, int n) {
FuncState *fs = ls->fs;
- luaX_checklimit(ls, fs->nactloc+n+1, MAXLOCALS, "local variables");
- fs->actloc[fs->nactloc+n] = luaI_registerlocalvar(ls, name);
+ luaX_checklimit(ls, fs->nactvar+n+1, MAXVARS, "local variables");
+ fs->actvar[fs->nactvar+n] = luaI_registerlocalvar(ls, name);
}
static void adjustlocalvars (LexState *ls, int nvars) {
FuncState *fs = ls->fs;
- while (nvars--)
- fs->f->locvars[fs->actloc[fs->nactloc++]].startpc = fs->pc;
+ fs->nactvar += nvars;
+ for (; nvars; nvars--) {
+ getlocvar(fs, fs->nactvar - nvars).startpc = fs->pc;
+ }
}
-static void removelocalvars (LexState *ls, int nvars) {
+static void removevars (LexState *ls, int tolevel) {
FuncState *fs = ls->fs;
- while (nvars--)
- fs->f->locvars[fs->actloc[--fs->nactloc]].endpc = fs->pc;
+ while (fs->nactvar > tolevel)
+ getlocvar(fs, --fs->nactvar).endpc = fs->pc;
}
static void new_localvarstr (LexState *ls, const char *name, int n) {
- new_localvar(ls, luaS_newfixed(ls->L, name), n);
+ new_localvar(ls, luaS_new(ls->L, name), n);
}
-static int search_local (LexState *ls, TString *n, expdesc *var) {
- FuncState *fs;
- int level = 0;
- for (fs=ls->fs; fs; fs=fs->prev) {
- int i;
- for (i=fs->nactloc-1; i >= 0; i--) {
- if (n == fs->f->locvars[fs->actloc[i]].varname) {
- var->k = VLOCAL;
- var->u.index = i;
- return level;
- }
- }
- level++; /* `var' not found; check outer level */
- }
- var->k = VGLOBAL; /* not found in any level; must be global */
- return -1;
+static void create_local (LexState *ls, const char *name) {
+ new_localvarstr(ls, name, 0);
+ adjustlocalvars(ls, 1);
}
-static void singlevar (LexState *ls, TString *n, expdesc *var) {
- int level = search_local(ls, n, var);
- if (level >= 1) /* neither local (0) nor global (-1)? */
- luaX_syntaxerror(ls, "cannot access a variable in outer scope", n->str);
- else if (level == -1) /* global? */
- var->u.index = string_constant(ls->fs, n);
+static int indexupvalue (FuncState *fs, TString *name, expdesc *v) {
+ int i;
+ Proto *f = fs->f;
+ for (i=0; i<f->nups; i++) {
+ if (fs->upvalues[i].k == v->k && fs->upvalues[i].info == v->info) {
+ lua_assert(fs->f->upvalues[i] == name);
+ return i;
+ }
+ }
+ /* new one */
+ luaX_checklimit(fs->ls, f->nups + 1, MAXUPVALUES, "upvalues");
+ luaM_growvector(fs->L, fs->f->upvalues, f->nups, fs->f->sizeupvalues,
+ TString *, MAX_INT, "");
+ fs->f->upvalues[f->nups] = name;
+ fs->upvalues[f->nups] = *v;
+ return f->nups++;
}
-static int indexupvalue (LexState *ls, expdesc *v) {
- FuncState *fs = ls->fs;
+static int searchvar (FuncState *fs, TString *n) {
int i;
- for (i=0; i<fs->nupvalues; i++) {
- if (fs->upvalues[i].k == v->k && fs->upvalues[i].u.index == v->u.index)
+ for (i=fs->nactvar-1; i >= 0; i--) {
+ if (n == getlocvar(fs, i).varname)
return i;
}
- /* new one */
- luaX_checklimit(ls, fs->nupvalues+1, MAXUPVALUES, "upvalues");
- fs->upvalues[fs->nupvalues] = *v;
- return fs->nupvalues++;
+ return -1; /* not found */
}
-static void pushupvalue (LexState *ls, TString *n) {
- FuncState *fs = ls->fs;
- expdesc v;
- int level = search_local(ls, n, &v);
- if (level == -1) { /* global? */
- if (fs->prev == NULL)
- luaX_syntaxerror(ls, "cannot access upvalue in main", n->str);
- v.u.index = string_constant(fs->prev, n);
+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 void 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 */
+ 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 */
+ }
+ else { /* not found at current level; try upper one */
+ singlevaraux(fs->prev, n, var, 0);
+ if (var->k == VGLOBAL) {
+ if (base)
+ var->info = luaK_stringK(fs, n); /* info points to global name */
+ }
+ else { /* LOCAL or UPVAL */
+ var->info = indexupvalue(fs, n, var);
+ var->k = VUPVAL; /* upvalue in this level */
+ }
+ }
}
- else if (level != 1)
- luaX_syntaxerror(ls,
- "upvalue must be global or local to immediately outer scope", n->str);
- luaK_code1(fs, OP_PUSHUPVALUE, indexupvalue(ls, &v));
}
-static void adjust_mult_assign (LexState *ls, int nvars, int nexps) {
+static TString *singlevar (LexState *ls, expdesc *var, int base) {
+ TString *varname = str_checkname(ls);
+ singlevaraux(ls->fs, varname, var, base);
+ return varname;
+}
+
+
+static void adjust_assign (LexState *ls, int nvars, int nexps, expdesc *e) {
FuncState *fs = ls->fs;
- int diff = nexps - nvars;
- if (nexps > 0 && luaK_lastisopen(fs)) { /* list ends in a function call */
- diff--; /* do not count function call itself */
- if (diff <= 0) { /* more variables than values? */
- luaK_setcallreturns(fs, -diff); /* function call provide extra values */
- diff = 0; /* no more difference */
+ int extra = nvars - nexps;
+ if (e->k == VCALL) {
+ extra++; /* includes call itself */
+ if (extra <= 0) extra = 0;
+ else luaK_reserveregs(fs, extra-1);
+ luaK_setcallreturns(fs, e, extra); /* call provides the difference */
+ }
+ 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);
}
- else /* more values than variables */
- luaK_setcallreturns(fs, 0); /* call should provide no value */
}
- /* push or pop eventual difference between list lengths */
- luaK_adjuststack(fs, diff);
}
static void code_params (LexState *ls, int nparams, int dots) {
FuncState *fs = ls->fs;
adjustlocalvars(ls, nparams);
- luaX_checklimit(ls, fs->nactloc, MAXPARAMS, "parameters");
- fs->f->numparams = fs->nactloc; /* `self' could be there already */
- fs->f->is_vararg = dots;
- if (dots) {
- new_localvarstr(ls, "arg", 0);
- adjustlocalvars(ls, 1);
- }
- luaK_deltastack(fs, fs->nactloc); /* count parameters in the stack */
+ luaX_checklimit(ls, fs->nactvar, MAXPARAMS, "parameters");
+ fs->f->numparams = cast(lu_byte, fs->nactvar);
+ fs->f->is_vararg = cast(lu_byte, dots);
+ if (dots)
+ create_local(ls, "arg");
+ luaK_reserveregs(fs, fs->nactvar); /* reserve register for parameters */
}
-static void enterbreak (FuncState *fs, Breaklabel *bl) {
- bl->stacklevel = fs->stacklevel;
+static void enterblock (FuncState *fs, BlockCnt *bl, int 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 leavebreak (FuncState *fs, Breaklabel *bl) {
+static void leaveblock (FuncState *fs) {
+ BlockCnt *bl = fs->bl;
fs->bl = bl->previous;
- LUA_ASSERT(bl->stacklevel == fs->stacklevel, "wrong levels");
- luaK_patchlist(fs, bl->breaklist, luaK_getlabel(fs));
+ removevars(fs->ls, bl->nactvar);
+ if (bl->upval)
+ luaK_codeABC(fs, OP_CLOSE, bl->nactvar, 0, 0);
+ lua_assert(bl->nactvar == fs->nactvar);
+ fs->freereg = fs->nactvar; /* free registers */
+ luaK_patchtohere(fs, bl->breaklist);
}
-static void pushclosure (LexState *ls, FuncState *func) {
+static void pushclosure (LexState *ls, FuncState *func, expdesc *v) {
FuncState *fs = ls->fs;
Proto *f = fs->f;
int i;
- for (i=0; i<func->nupvalues; i++)
- luaK_tostack(ls, &func->upvalues[i], 1);
- luaM_growvector(ls->L, f->kproto, f->nkproto, 1, Proto *,
- "constant table overflow", MAXARG_A);
- f->kproto[f->nkproto++] = func->f;
- luaK_code2(fs, OP_CLOSURE, f->nkproto-1, func->nupvalues);
+ luaM_growvector(ls->L, f->p, fs->np, f->sizep, Proto *,
+ MAXARG_Bx, "constant table overflow");
+ f->p[fs->np++] = 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) {
Proto *f = luaF_newproto(ls->L);
+ fs->f = f;
fs->prev = ls->fs; /* linked list of funcstates */
fs->ls = ls;
fs->L = ls->L;
ls->fs = fs;
- fs->stacklevel = 0;
- fs->nactloc = 0;
- fs->nupvalues = 0;
- fs->bl = NULL;
- fs->f = f;
- f->source = ls->source;
fs->pc = 0;
fs->lasttarget = 0;
- fs->lastline = 0;
- fs->jlt = NO_JUMP;
- f->code = NULL;
- f->maxstacksize = 0;
- f->numparams = 0; /* default for main chunk */
- f->is_vararg = 0; /* default for main chunk */
+ fs->jpc = NO_JUMP;
+ fs->freereg = 0;
+ fs->nk = 0;
+ fs->h = luaH_new(ls->L, 0, 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 */
}
@@ -328,33 +343,40 @@ static void close_func (LexState *ls) {
lua_State *L = ls->L;
FuncState *fs = ls->fs;
Proto *f = fs->f;
- luaK_code0(fs, OP_END);
- luaK_getlabel(fs); /* close eventual list of pending jumps */
- luaM_reallocvector(L, f->code, fs->pc, Instruction);
- luaM_reallocvector(L, f->kstr, f->nkstr, TString *);
- luaM_reallocvector(L, f->knum, f->nknum, Number);
- luaM_reallocvector(L, f->kproto, f->nkproto, Proto *);
- removelocalvars(ls, fs->nactloc);
- luaM_reallocvector(L, f->locvars, f->nlocvars, LocVar);
- luaM_reallocvector(L, f->lineinfo, f->nlineinfo+1, int);
- f->lineinfo[f->nlineinfo++] = MAX_INT; /* end flag */
- luaF_protook(L, f, fs->pc); /* proto is ok now */
+ removevars(ls, 0);
+ luaK_codeABC(fs, OP_RETURN, 0, 1, 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, TObject);
+ 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;
- LUA_ASSERT(fs->bl == NULL, "wrong list end");
}
-Proto *luaY_parser (lua_State *L, ZIO *z) {
+Proto *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff) {
struct LexState lexstate;
struct FuncState funcstate;
+ lexstate.buff = buff;
+ lexstate.nestlevel = 0;
luaX_setinput(L, &lexstate, z, luaS_new(L, zname(z)));
open_func(&lexstate, &funcstate);
next(&lexstate); /* read first token */
chunk(&lexstate);
check_condition(&lexstate, (lexstate.t.token == TK_EOS), "<eof> expected");
close_func(&lexstate);
- LUA_ASSERT(funcstate.prev == NULL, "wrong list end");
- LUA_ASSERT(funcstate.nupvalues == 0, "no upvalues in main");
+ lua_assert(funcstate.prev == NULL);
+ lua_assert(funcstate.f->nups == 0);
+ lua_assert(lexstate.nestlevel == 0);
return funcstate.f;
}
@@ -365,235 +387,239 @@ Proto *luaY_parser (lua_State *L, ZIO *z) {
/*============================================================*/
-static int explist1 (LexState *ls) {
- /* explist1 -> expr { ',' expr } */
- int n = 1; /* at least one expression */
- expdesc v;
- expr(ls, &v);
- while (ls->t.token == ',') {
- luaK_tostack(ls, &v, 1); /* gets only 1 value from previous expression */
- next(ls); /* skip comma */
- expr(ls, &v);
- n++;
- }
- luaK_tostack(ls, &v, 0); /* keep open number of values of last expression */
- return n;
+static void luaY_field (LexState *ls, expdesc *v) {
+ /* field -> ['.' | ':'] NAME */
+ FuncState *fs = ls->fs;
+ expdesc key;
+ luaK_exp2anyreg(fs, v);
+ next(ls); /* skip the dot or colon */
+ checkname(ls, &key);
+ luaK_indexed(fs, v, &key);
}
-static void funcargs (LexState *ls, int slf) {
+static void luaY_index (LexState *ls, expdesc *v) {
+ /* index -> '[' expr ']' */
+ next(ls); /* skip the '[' */
+ expr(ls, v);
+ luaK_exp2val(ls->fs, v);
+ check(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 slevel = fs->stacklevel - slf - 1; /* where is func in the stack */
- switch (ls->t.token) {
- case '(': { /* funcargs -> '(' [ explist1 ] ')' */
- int line = ls->linenumber;
- int nargs = 0;
- next(ls);
- if (ls->t.token != ')') /* arg list not empty? */
- nargs = explist1(ls);
- check_match(ls, ')', '(', line);
-#ifdef LUA_COMPAT_ARGRET
- if (nargs > 0) /* arg list is not empty? */
- luaK_setcallreturns(fs, 1); /* last call returns only 1 value */
-#else
- UNUSED(nargs); /* to avoid warnings */
-#endif
- break;
- }
- case '{': { /* funcargs -> constructor */
- constructor(ls);
- break;
- }
- case TK_STRING: { /* funcargs -> STRING */
- code_string(ls, ls->t.seminfo.ts); /* must use `seminfo' before `next' */
- next(ls);
- break;
- }
- default: {
- luaK_error(ls, "function arguments expected");
- break;
- }
+ int reg = ls->fs->freereg;
+ expdesc key, val;
+ if (ls->t.token == TK_NAME) {
+ luaX_checklimit(ls, cc->nh, MAX_INT, "items in a constructor");
+ cc->nh++;
+ checkname(ls, &key);
+ }
+ else /* ls->t.token == '[' */
+ luaY_index(ls, &key);
+ check(ls, '=');
+ luaK_exp2RK(fs, &key);
+ expr(ls, &val);
+ luaK_codeABC(fs, OP_SETTABLE, cc->t->info, luaK_exp2RK(fs, &key),
+ 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_codeABx(fs, OP_SETLIST, cc->t->info, cc->na-1); /* flush */
+ cc->tostore = 0; /* no more items pending */
+ fs->freereg = cc->t->info + 1; /* free registers */
}
- fs->stacklevel = slevel; /* call will remove function and arguments */
- luaK_code2(fs, OP_CALL, slevel, MULT_RET);
}
-static void var_or_func_tail (LexState *ls, expdesc *v) {
- for (;;) {
- switch (ls->t.token) {
- case '.': { /* var_or_func_tail -> '.' NAME */
- next(ls);
- luaK_tostack(ls, v, 1); /* `v' must be on stack */
- luaK_kstr(ls, checkname(ls));
- v->k = VINDEXED;
- break;
- }
- case '[': { /* var_or_func_tail -> '[' exp1 ']' */
- next(ls);
- luaK_tostack(ls, v, 1); /* `v' must be on stack */
- v->k = VINDEXED;
- exp1(ls);
- check(ls, ']');
+static void lastlistfield (FuncState *fs, struct ConsControl *cc) {
+ if (cc->tostore == 0) return;
+ if (cc->v.k == VCALL) {
+ luaK_setcallreturns(fs, &cc->v, LUA_MULTRET);
+ luaK_codeABx(fs, OP_SETLISTO, cc->t->info, cc->na-1);
+ }
+ else {
+ if (cc->v.k != VVOID)
+ luaK_exp2nextreg(fs, &cc->v);
+ luaK_codeABx(fs, OP_SETLIST, cc->t->info, cc->na-1);
+ }
+ fs->freereg = cc->t->info + 1; /* free registers */
+}
+
+
+static void listfield (LexState *ls, struct ConsControl *cc) {
+ expr(ls, &cc->v);
+ luaX_checklimit(ls, 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) */
+ check(ls, '{');
+ do {
+ lua_assert(cc.v.k == VVOID || cc.tostore > 0);
+ testnext(ls, ';'); /* compatibility only */
+ if (ls->t.token == '}') break;
+ closelistfield(fs, &cc);
+ switch(ls->t.token) {
+ case TK_NAME: { /* may be listfields or recfields */
+ lookahead(ls);
+ if (ls->lookahead.token != '=') /* expression? */
+ listfield(ls, &cc);
+ else
+ recfield(ls, &cc);
break;
}
- case ':': { /* var_or_func_tail -> ':' NAME funcargs */
- int name;
- next(ls);
- name = checkname(ls);
- luaK_tostack(ls, v, 1); /* `v' must be on stack */
- luaK_code1(ls->fs, OP_PUSHSELF, name);
- funcargs(ls, 1);
- v->k = VEXP;
- v->u.l.t = v->u.l.f = NO_JUMP;
+ case '[': { /* constructor_item -> recfield */
+ recfield(ls, &cc);
break;
}
- case '(': case TK_STRING: case '{': { /* var_or_func_tail -> funcargs */
- luaK_tostack(ls, v, 1); /* `v' must be on stack */
- funcargs(ls, 0);
- v->k = VEXP;
- v->u.l.t = v->u.l.f = NO_JUMP;
+ default: { /* constructor_part -> listfield */
+ listfield(ls, &cc);
break;
}
- default: return; /* should be follow... */
}
- }
-}
-
-
-static void var_or_func (LexState *ls, expdesc *v) {
- /* var_or_func -> ['%'] NAME var_or_func_tail */
- if (optional(ls, '%')) { /* upvalue? */
- pushupvalue(ls, str_checkname(ls));
- v->k = VEXP;
- v->u.l.t = v->u.l.f = NO_JUMP;
- }
- else /* variable name */
- singlevar(ls, str_checkname(ls), v);
- var_or_func_tail(ls, v);
+ } 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_log2(cc.nh)+1); /* set initial table size */
}
+/* }====================================================================== */
-/*
-** {======================================================================
-** Rules for Constructors
-** =======================================================================
-*/
-
-static void recfield (LexState *ls) {
- /* recfield -> (NAME | '['exp1']') = exp1 */
- switch (ls->t.token) {
- case TK_NAME: {
- luaK_kstr(ls, checkname(ls));
- break;
- }
- case '[': {
- next(ls);
- exp1(ls);
- check(ls, ']');
- break;
- }
- default: luaK_error(ls, "<name> or `[' expected");
+static void parlist (LexState *ls) {
+ /* parlist -> [ param { `,' param } ] */
+ int nparams = 0;
+ int dots = 0;
+ if (ls->t.token != ')') { /* is `parlist' not empty? */
+ do {
+ switch (ls->t.token) {
+ case TK_DOTS: dots = 1; next(ls); break;
+ case TK_NAME: new_localvar(ls, str_checkname(ls), nparams++); break;
+ default: luaX_syntaxerror(ls, "<name> or `...' expected");
+ }
+ } while (!dots && testnext(ls, ','));
}
- check(ls, '=');
- exp1(ls);
+ code_params(ls, nparams, dots);
}
-static int recfields (LexState *ls) {
- /* recfields -> recfield { ',' recfield } [','] */
- FuncState *fs = ls->fs;
- int n = 1; /* at least one element */
- recfield(ls);
- while (ls->t.token == ',') {
- next(ls);
- if (ls->t.token == ';' || ls->t.token == '}')
- break;
- recfield(ls);
- n++;
- if (n%RFIELDS_PER_FLUSH == 0)
- luaK_code1(fs, OP_SETMAP, RFIELDS_PER_FLUSH);
- }
- luaK_code1(fs, OP_SETMAP, n%RFIELDS_PER_FLUSH);
- return n;
+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;
+ check(ls, '(');
+ if (needself)
+ create_local(ls, "self");
+ parlist(ls);
+ check(ls, ')');
+ chunk(ls);
+ check_match(ls, TK_END, TK_FUNCTION, line);
+ close_func(ls);
+ pushclosure(ls, &new_fs, e);
}
-static int listfields (LexState *ls) {
- /* listfields -> exp1 { ',' exp1 } [','] */
- FuncState *fs = ls->fs;
- int n = 1; /* at least one element */
- exp1(ls);
- while (ls->t.token == ',') {
- next(ls);
- if (ls->t.token == ';' || ls->t.token == '}')
- break;
- exp1(ls);
+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++;
- luaX_checklimit(ls, n/LFIELDS_PER_FLUSH, MAXARG_A,
- "`item groups' in a list initializer");
- if (n%LFIELDS_PER_FLUSH == 0)
- luaK_code2(fs, OP_SETLIST, n/LFIELDS_PER_FLUSH - 1, LFIELDS_PER_FLUSH);
}
- luaK_code2(fs, OP_SETLIST, n/LFIELDS_PER_FLUSH, n%LFIELDS_PER_FLUSH);
return n;
}
-
-static void constructor_part (LexState *ls, Constdesc *cd) {
+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 ';': case '}': { /* constructor_part -> empty */
- cd->n = 0;
- cd->k = ls->t.token;
+ case '(': { /* funcargs -> `(' [ explist1 ] `)' */
+ if (line != ls->lastline)
+ luaX_syntaxerror(ls,"ambiguous syntax (function call x new statement)");
+ next(ls);
+ if (ls->t.token == ')') /* arg list is empty? */
+ args.k = VVOID;
+ else {
+ explist1(ls, &args);
+ luaK_setcallreturns(fs, &args, LUA_MULTRET);
+ }
+ check_match(ls, ')', '(', line);
break;
}
- case TK_NAME: { /* may be listfields or recfields */
- lookahead(ls);
- if (ls->lookahead.token != '=') /* expression? */
- goto case_default;
- /* else go through to recfields */
- }
- case '[': { /* constructor_part -> recfields */
- cd->n = recfields(ls);
- cd->k = 1; /* record */
+ case '{': { /* funcargs -> constructor */
+ constructor(ls, &args);
break;
}
- default: { /* constructor_part -> listfields */
- case_default:
- cd->n = listfields(ls);
- cd->k = 0; /* list */
+ case TK_STRING: { /* funcargs -> STRING */
+ codestring(ls, &args, ls->t.seminfo.ts);
+ next(ls); /* must use `seminfo' before `next' */
break;
}
+ default: {
+ luaX_syntaxerror(ls, "function arguments expected");
+ return;
+ }
}
-}
-
-
-static void constructor (LexState *ls) {
- /* constructor -> '{' constructor_part [';' constructor_part] '}' */
- FuncState *fs = ls->fs;
- int line = ls->linenumber;
- int pc = luaK_code1(fs, OP_CREATETABLE, 0);
- int nelems;
- Constdesc cd;
- check(ls, '{');
- constructor_part(ls, &cd);
- nelems = cd.n;
- if (optional(ls, ';')) {
- Constdesc other_cd;
- constructor_part(ls, &other_cd);
- check_condition(ls, (cd.k != other_cd.k), "invalid constructor syntax");
- nelems += other_cd.n;
+ lua_assert(f->k == VNONRELOC);
+ base = f->info; /* base register for call */
+ if (args.k == VCALL)
+ nparams = LUA_MULTRET; /* open call */
+ else {
+ if (args.k != VVOID)
+ luaK_exp2nextreg(fs, &args); /* close last argument */
+ nparams = fs->freereg - (base+1);
}
- check_match(ls, '}', '{', line);
- luaX_checklimit(ls, nelems, MAXARG_U, "elements in a table constructor");
- SETARG_U(fs->f->code[pc], nelems); /* set initial table size */
+ 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 */
}
-/* }====================================================================== */
-
@@ -604,58 +630,121 @@ static void constructor (LexState *ls) {
*/
-static void simpleexp (LexState *ls, expdesc *v) {
- FuncState *fs = ls->fs;
+static void prefixexp (LexState *ls, expdesc *v) {
+ /* prefixexp -> NAME | '(' expr ')' */
switch (ls->t.token) {
- case TK_NUMBER: { /* simpleexp -> NUMBER */
- Number r = ls->t.seminfo.r;
+ case '(': {
+ int line = ls->linenumber;
next(ls);
- luaK_number(fs, r);
+ expr(ls, v);
+ check_match(ls, ')', '(', line);
+ luaK_dischargevars(ls->fs, v);
+ return;
+ }
+ case TK_NAME: {
+ singlevar(ls, v, 1);
+ return;
+ }
+#ifdef LUA_COMPATUPSYNTAX
+ case '%': { /* for compatibility only */
+ TString *varname;
+ int line = ls->linenumber;
+ next(ls); /* skip `%' */
+ varname = singlevar(ls, v, 1);
+ if (v->k != VUPVAL)
+ luaX_errorline(ls, "global upvalues are obsolete",
+ getstr(varname), line);
+ return;
+ }
+#endif
+ 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 */
+ luaY_field(ls, v);
+ break;
+ }
+ case '[': { /* `[' exp1 `]' */
+ expdesc key;
+ luaK_exp2anyreg(fs, v);
+ luaY_index(ls, &key);
+ luaK_indexed(fs, v, &key);
+ break;
+ }
+ case ':': { /* `:' NAME funcargs */
+ expdesc key;
+ 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 | constructor | FUNCTION body
+ | primaryexp */
+ switch (ls->t.token) {
+ case TK_NUMBER: {
+ init_exp(v, VK, luaK_numberK(ls->fs, ls->t.seminfo.r));
+ next(ls); /* must use `seminfo' before `next' */
break;
}
- case TK_STRING: { /* simpleexp -> STRING */
- code_string(ls, ls->t.seminfo.ts); /* must use `seminfo' before `next' */
- next(ls);
+ case TK_STRING: {
+ codestring(ls, v, ls->t.seminfo.ts);
+ next(ls); /* must use `seminfo' before `next' */
break;
}
- case TK_NIL: { /* simpleexp -> NIL */
- luaK_adjuststack(fs, -1);
+ case TK_NIL: {
+ init_exp(v, VNIL, 0);
next(ls);
break;
}
- case '{': { /* simpleexp -> constructor */
- constructor(ls);
+ case TK_TRUE: {
+ init_exp(v, VTRUE, 0);
+ next(ls);
break;
}
- case TK_FUNCTION: { /* simpleexp -> FUNCTION body */
+ case TK_FALSE: {
+ init_exp(v, VFALSE, 0);
next(ls);
- body(ls, 0, ls->linenumber);
break;
}
- case '(': { /* simpleexp -> '(' expr ')' */
- next(ls);
- expr(ls, v);
- check(ls, ')');
- return;
+ case '{': { /* constructor */
+ constructor(ls, v);
+ break;
}
- case TK_NAME: case '%': {
- var_or_func(ls, v);
- return;
+ case TK_FUNCTION: {
+ next(ls);
+ body(ls, v, 0, ls->linenumber);
+ break;
}
default: {
- luaK_error(ls, "<expression> expected");
- return;
+ primaryexp(ls, v);
+ break;
}
}
- v->k = VEXP;
- v->u.l.t = v->u.l.f = NO_JUMP;
-}
-
-
-static void exp1 (LexState *ls) {
- expdesc v;
- expr(ls, &v);
- luaK_tostack(ls, &v, 1);
}
@@ -690,17 +779,17 @@ static BinOpr getbinopr (int op) {
static const struct {
- char left; /* left priority for each binary operator */
- char right; /* right priority */
+ lu_byte left; /* left priority for each binary operator */
+ lu_byte right; /* right priority */
} priority[] = { /* ORDER OPR */
- {5, 5}, {5, 5}, {6, 6}, {6, 6}, /* arithmetic */
- {9, 8}, {4, 3}, /* power and concat (right associative) */
- {2, 2}, {2, 2}, /* equality */
- {2, 2}, {2, 2}, {2, 2}, {2, 2}, /* order */
- {1, 1}, {1, 1} /* logical */
+ {6, 6}, {6, 6}, {7, 7}, {7, 7}, /* arithmetic */
+ {10, 9}, {5, 4}, /* power and concat (right associative) */
+ {3, 3}, {3, 3}, /* equality */
+ {3, 3}, {3, 3}, {3, 3}, {3, 3}, /* order */
+ {2, 2}, {1, 1} /* logical (and/or) */
};
-#define UNARY_PRIORITY 7 /* priority for unary operators */
+#define UNARY_PRIORITY 8 /* priority for unary operators */
/*
@@ -709,25 +798,28 @@ static const struct {
*/
static BinOpr subexpr (LexState *ls, expdesc *v, int limit) {
BinOpr op;
- UnOpr uop = getunopr(ls->t.token);
+ UnOpr uop;
+ enterlevel(ls);
+ uop = getunopr(ls->t.token);
if (uop != OPR_NOUNOPR) {
next(ls);
subexpr(ls, v, UNARY_PRIORITY);
- luaK_prefix(ls, uop, v);
+ 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) {
+ while (op != OPR_NOBINOPR && cast(int, priority[op].left) > limit) {
expdesc v2;
BinOpr nextop;
next(ls);
- luaK_infix(ls, op, v);
+ luaK_infix(ls->fs, op, v);
/* read sub-expression with higher priority */
- nextop = subexpr(ls, &v2, priority[op].right);
- luaK_posfix(ls, op, v, &v2);
+ nextop = subexpr(ls, &v2, cast(int, priority[op].right));
+ luaK_posfix(ls->fs, op, v, &v2);
op = nextop;
}
+ leavelevel(ls);
return op; /* return first untreated operator */
}
@@ -739,6 +831,7 @@ static void expr (LexState *ls, expdesc *v) {
/* }==================================================================== */
+
/*
** {======================================================================
** Rules for Statements
@@ -759,61 +852,151 @@ static int block_follow (int token) {
static void block (LexState *ls) {
/* block -> chunk */
FuncState *fs = ls->fs;
- int nactloc = fs->nactloc;
+ BlockCnt bl;
+ enterblock(fs, &bl, 0);
chunk(ls);
- luaK_adjuststack(fs, fs->nactloc - nactloc); /* remove local variables */
- removelocalvars(ls, fs->nactloc - nactloc);
+ lua_assert(bl.breaklist == NO_JUMP);
+ leaveblock(fs);
}
-static int assignment (LexState *ls, expdesc *v, int nvars) {
- int left = 0; /* number of values left in the stack after assignment */
- luaX_checklimit(ls, nvars, MAXVARSLH, "variables in a multiple assignment");
- if (ls->t.token == ',') { /* assignment -> ',' NAME assignment */
- expdesc nv;
- next(ls);
- var_or_func(ls, &nv);
- check_condition(ls, (nv.k != VEXP), "syntax error");
- left = assignment(ls, &nv, nvars+1);
+/*
+** 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.info == v->info) { /* conflict? */
+ conflict = 1;
+ lh->v.info = extra; /* previous assignment will use safe copy */
+ }
+ if (lh->v.aux == v->info) { /* conflict? */
+ conflict = 1;
+ lh->v.aux = extra; /* previous assignment will use safe copy */
+ }
+ }
+ }
+ if (conflict) {
+ luaK_codeABC(fs, OP_MOVE, fs->freereg, v->info, 0); /* make copy */
+ luaK_reserveregs(fs, 1);
}
- else { /* assignment -> '=' explist1 */
+}
+
+
+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;
check(ls, '=');
- nexps = explist1(ls);
- adjust_mult_assign(ls, nvars, nexps);
- }
- if (v->k != VINDEXED)
- luaK_storevar(ls, v);
- else { /* there may be garbage between table-index and value */
- luaK_code2(ls->fs, OP_SETTABLE, left+nvars+2, 1);
- left += 2;
+ 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_setcallreturns(ls->fs, &e, 1); /* close last expression */
+ luaK_storevar(ls->fs, &lh->v, &e);
+ return; /* avoid default */
+ }
}
- return left;
+ init_exp(&e, VNONRELOC, ls->fs->freereg-1); /* default assignment */
+ luaK_storevar(ls->fs, &lh->v, &e);
}
static void cond (LexState *ls, expdesc *v) {
/* cond -> exp */
expr(ls, v); /* read condition */
- luaK_goiftrue(ls->fs, v, 0);
+ if (v->k == VNIL) v->k = VFALSE; /* `falses' are all equal here */
+ luaK_goiftrue(ls->fs, v);
+ luaK_patchtohere(ls->fs, v->t);
}
+/*
+** The while statement optimizes its code by coding the condition
+** after its body (and thus avoiding one jump in the loop).
+*/
+
+/*
+** maximum size of expressions for optimizing `while' code
+*/
+#ifndef MAXEXPWHILE
+#define MAXEXPWHILE 100
+#endif
+
+/*
+** the call `luaK_goiffalse' may grow the size of an expression by
+** at most this:
+*/
+#define EXTRAEXP 5
+
static void whilestat (LexState *ls, int line) {
/* whilestat -> WHILE cond DO block END */
+ Instruction codeexp[MAXEXPWHILE + EXTRAEXP];
+ int lineexp;
+ int i;
+ int sizeexp;
FuncState *fs = ls->fs;
- int while_init = luaK_getlabel(fs);
+ int whileinit, blockinit, expinit;
expdesc v;
- Breaklabel bl;
- enterbreak(fs, &bl);
- next(ls);
- cond(ls, &v);
+ BlockCnt bl;
+ next(ls); /* skip WHILE */
+ whileinit = luaK_jump(fs); /* jump to condition (which will be moved) */
+ expinit = luaK_getlabel(fs);
+ expr(ls, &v); /* parse condition */
+ if (v.k == VK) v.k = VTRUE; /* `trues' are all equal here */
+ lineexp = ls->linenumber;
+ luaK_goiffalse(fs, &v);
+ luaK_concat(fs, &v.f, fs->jpc);
+ fs->jpc = NO_JUMP;
+ sizeexp = fs->pc - expinit; /* size of expression code */
+ if (sizeexp > MAXEXPWHILE)
+ luaX_syntaxerror(ls, "`while' condition too complex");
+ for (i = 0; i < sizeexp; i++) /* save `exp' code */
+ codeexp[i] = fs->f->code[expinit + i];
+ fs->pc = expinit; /* remove `exp' code */
+ enterblock(fs, &bl, 1);
check(ls, TK_DO);
+ blockinit = luaK_getlabel(fs);
block(ls);
- luaK_patchlist(fs, luaK_jump(fs), while_init);
- luaK_patchlist(fs, v.u.l.f, luaK_getlabel(fs));
+ luaK_patchtohere(fs, whileinit); /* initial jump jumps to here */
+ /* move `exp' back to code */
+ if (v.t != NO_JUMP) v.t += fs->pc - expinit;
+ if (v.f != NO_JUMP) v.f += fs->pc - expinit;
+ for (i=0; i<sizeexp; i++)
+ luaK_code(fs, codeexp[i], lineexp);
check_match(ls, TK_END, TK_WHILE, line);
- leavebreak(fs, &bl);
+ leaveblock(fs);
+ luaK_patchlist(fs, v.t, blockinit); /* true conditions go back to loop */
+ luaK_patchtohere(fs, v.f); /* false conditions finish the loop */
}
@@ -822,64 +1005,86 @@ static void repeatstat (LexState *ls, int line) {
FuncState *fs = ls->fs;
int repeat_init = luaK_getlabel(fs);
expdesc v;
- Breaklabel bl;
- enterbreak(fs, &bl);
+ BlockCnt bl;
+ enterblock(fs, &bl, 1);
next(ls);
block(ls);
check_match(ls, TK_UNTIL, TK_REPEAT, line);
cond(ls, &v);
- luaK_patchlist(fs, v.u.l.f, repeat_init);
- leavebreak(fs, &bl);
+ luaK_patchlist(fs, v.f, repeat_init);
+ leaveblock(fs);
}
-static void forbody (LexState *ls, int nvar, OpCode prepfor, OpCode loopfor) {
- /* forbody -> DO block END */
+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) {
+ BlockCnt bl;
FuncState *fs = ls->fs;
- int prep = luaK_code1(fs, prepfor, NO_JUMP);
- int blockinit = luaK_getlabel(fs);
+ int prep, endfor;
+ adjustlocalvars(ls, nvars); /* scope for all variables */
check(ls, TK_DO);
- adjustlocalvars(ls, nvar); /* scope for control variables */
+ enterblock(fs, &bl, 1); /* loop block */
+ prep = luaK_getlabel(fs);
block(ls);
- luaK_patchlist(fs, luaK_code1(fs, loopfor, NO_JUMP), blockinit);
- luaK_patchlist(fs, prep, luaK_getlabel(fs));
- removelocalvars(ls, nvar);
+ luaK_patchtohere(fs, prep-1);
+ endfor = (isnum) ? luaK_codeAsBx(fs, OP_FORLOOP, base, NO_JUMP) :
+ luaK_codeABC(fs, OP_TFORLOOP, base, 0, nvars - 3);
+ luaK_fixline(fs, line); /* pretend that `OP_FOR' starts the loop */
+ luaK_patchlist(fs, (isnum) ? endfor : luaK_jump(fs), prep);
+ leaveblock(fs);
}
-static void fornum (LexState *ls, TString *varname) {
- /* fornum -> NAME = exp1,exp1[,exp1] forbody */
+static void fornum (LexState *ls, TString *varname, int line) {
+ /* fornum -> NAME = exp1,exp1[,exp1] DO body */
FuncState *fs = ls->fs;
+ int base = fs->freereg;
+ new_localvar(ls, varname, 0);
+ new_localvarstr(ls, "(for limit)", 1);
+ new_localvarstr(ls, "(for step)", 2);
check(ls, '=');
exp1(ls); /* initial value */
check(ls, ',');
exp1(ls); /* limit */
- if (optional(ls, ','))
+ if (testnext(ls, ','))
exp1(ls); /* optional step */
- else
- luaK_code1(fs, OP_PUSHINT, 1); /* default step */
- new_localvar(ls, varname, 0);
- new_localvarstr(ls, "(limit)", 1);
- new_localvarstr(ls, "(step)", 2);
- forbody(ls, 3, OP_FORPREP, OP_FORLOOP);
+ else { /* default step = 1 */
+ luaK_codeABx(fs, OP_LOADK, fs->freereg, luaK_numberK(fs, 1));
+ luaK_reserveregs(fs, 1);
+ }
+ luaK_codeABC(fs, OP_SUB, fs->freereg - 3, fs->freereg - 3, fs->freereg - 1);
+ luaK_jump(fs);
+ forbody(ls, base, line, 3, 1);
}
static void forlist (LexState *ls, TString *indexname) {
- /* forlist -> NAME,NAME IN exp1 forbody */
- TString *valname;
- check(ls, ',');
- valname = str_checkname(ls);
- /* next test is dirty, but avoids `in' being a reserved word */
- check_condition(ls,
- (ls->t.token == TK_NAME && ls->t.seminfo.ts == luaS_new(ls->L, "in")),
- "`in' expected");
- next(ls); /* skip `in' */
- exp1(ls); /* table */
- new_localvarstr(ls, "(table)", 0);
- new_localvar(ls, indexname, 1);
- new_localvar(ls, valname, 2);
- forbody(ls, 3, OP_LFORPREP, OP_LFORLOOP);
+ /* forlist -> NAME {,NAME} IN explist1 DO body */
+ FuncState *fs = ls->fs;
+ expdesc e;
+ int nvars = 0;
+ int line;
+ int base = fs->freereg;
+ new_localvarstr(ls, "(for generator)", nvars++);
+ new_localvarstr(ls, "(for state)", nvars++);
+ new_localvar(ls, indexname, nvars++);
+ while (testnext(ls, ','))
+ new_localvar(ls, str_checkname(ls), nvars++);
+ check(ls, TK_IN);
+ line = ls->linenumber;
+ adjust_assign(ls, nvars, explist1(ls, &e), &e);
+ luaK_checkstack(fs, 3); /* extra space to call generator */
+ luaK_codeAsBx(fs, OP_TFORPREP, base, NO_JUMP);
+ forbody(ls, base, line, nvars, 0);
}
@@ -887,17 +1092,17 @@ static void forstat (LexState *ls, int line) {
/* forstat -> fornum | forlist */
FuncState *fs = ls->fs;
TString *varname;
- Breaklabel bl;
- enterbreak(fs, &bl);
+ BlockCnt bl;
+ enterblock(fs, &bl, 0); /* block to control variable scope */
next(ls); /* skip `for' */
varname = str_checkname(ls); /* first variable name */
switch (ls->t.token) {
- case '=': fornum(ls, varname); break;
- case ',': forlist(ls, varname); break;
- default: luaK_error(ls, "`=' or `,' expected");
+ case '=': fornum(ls, varname, line); break;
+ case ',': case TK_IN: forlist(ls, varname); break;
+ default: luaX_syntaxerror(ls, "`=' or `in' expected");
}
check_match(ls, TK_END, TK_FOR, line);
- leavebreak(fs, &bl);
+ leaveblock(fs);
}
@@ -918,49 +1123,60 @@ static void ifstat (LexState *ls, int line) {
test_then_block(ls, &v); /* IF cond THEN block */
while (ls->t.token == TK_ELSEIF) {
luaK_concat(fs, &escapelist, luaK_jump(fs));
- luaK_patchlist(fs, v.u.l.f, luaK_getlabel(fs));
+ luaK_patchtohere(fs, v.f);
test_then_block(ls, &v); /* ELSEIF cond THEN block */
}
if (ls->t.token == TK_ELSE) {
luaK_concat(fs, &escapelist, luaK_jump(fs));
- luaK_patchlist(fs, v.u.l.f, luaK_getlabel(fs));
- next(ls); /* skip ELSE */
+ luaK_patchtohere(fs, v.f);
+ next(ls); /* skip ELSE (after patch, for correct line info) */
block(ls); /* `else' part */
}
else
- luaK_concat(fs, &escapelist, v.u.l.f);
- luaK_patchlist(fs, escapelist, luaK_getlabel(fs));
+ luaK_concat(fs, &escapelist, v.f);
+ luaK_patchtohere(fs, escapelist);
check_match(ls, TK_END, TK_IF, line);
}
+static void localfunc (LexState *ls) {
+ expdesc v, b;
+ new_localvar(ls, str_checkname(ls), 0);
+ init_exp(&v, VLOCAL, ls->fs->freereg++);
+ adjustlocalvars(ls, 1);
+ body(ls, &b, 0, ls->linenumber);
+ luaK_storevar(ls->fs, &v, &b);
+}
+
+
static void localstat (LexState *ls) {
- /* stat -> LOCAL NAME {',' NAME} ['=' explist1] */
+ /* stat -> LOCAL NAME {`,' NAME} [`=' explist1] */
int nvars = 0;
int nexps;
+ expdesc e;
do {
- next(ls); /* skip LOCAL or ',' */
new_localvar(ls, str_checkname(ls), nvars++);
- } while (ls->t.token == ',');
- if (optional(ls, '='))
- nexps = explist1(ls);
- else
+ } while (testnext(ls, ','));
+ if (testnext(ls, '='))
+ nexps = explist1(ls, &e);
+ else {
+ e.k = VVOID;
nexps = 0;
- adjust_mult_assign(ls, nvars, nexps);
+ }
+ adjust_assign(ls, nvars, nexps, &e);
adjustlocalvars(ls, nvars);
}
static int funcname (LexState *ls, expdesc *v) {
- /* funcname -> NAME [':' NAME | '.' NAME] */
+ /* funcname -> NAME {field} [`:' NAME] */
int needself = 0;
- singlevar(ls, str_checkname(ls), v);
- if (ls->t.token == ':' || ls->t.token == '.') {
- needself = (ls->t.token == ':');
- next(ls);
- luaK_tostack(ls, v, 1);
- luaK_kstr(ls, checkname(ls));
- v->k = VINDEXED;
+ singlevar(ls, v, 1);
+ while (ls->t.token == '.')
+ luaY_field(ls, v);
+ if (ls->t.token == ':') {
+ needself = 1;
+ luaY_field(ls, v);
}
return needself;
}
@@ -969,26 +1185,26 @@ static int funcname (LexState *ls, expdesc *v) {
static void funcstat (LexState *ls, int line) {
/* funcstat -> FUNCTION funcname body */
int needself;
- expdesc v;
+ expdesc v, b;
next(ls); /* skip FUNCTION */
needself = funcname(ls, &v);
- body(ls, needself, line);
- luaK_storevar(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 namestat (LexState *ls) {
- /* stat -> func | ['%'] NAME assignment */
+static void exprstat (LexState *ls) {
+ /* stat -> func | assignment */
FuncState *fs = ls->fs;
- expdesc v;
- var_or_func(ls, &v);
- if (v.k == VEXP) { /* stat -> func */
- check_condition(ls, luaK_lastisopen(fs), "syntax error"); /* an upvalue? */
- luaK_setcallreturns(fs, 0); /* call statement uses no results */
+ struct LHS_assign v;
+ primaryexp(ls, &v.v);
+ if (v.v.k == VCALL) { /* stat -> func */
+ luaK_setcallreturns(fs, &v.v, 0); /* call statement uses no results */
}
- else { /* stat -> ['%'] NAME assignment */
- int left = assignment(ls, &v, 1);
- luaK_adjuststack(fs, left); /* remove eventual garbage left on stack */
+ else { /* stat -> assignment */
+ v.prev = NULL;
+ assignment(ls, &v, 1);
}
}
@@ -996,30 +1212,55 @@ static void namestat (LexState *ls) {
static void retstat (LexState *ls) {
/* stat -> RETURN explist */
FuncState *fs = ls->fs;
+ expdesc e;
+ int first, nret; /* registers with returned values */
next(ls); /* skip RETURN */
- if (!block_follow(ls->t.token) && ls->t.token != ';')
- explist1(ls); /* optional return values */
- luaK_code1(fs, OP_RETURN, ls->fs->nactloc);
- fs->stacklevel = fs->nactloc; /* removes all temp values */
+ if (block_follow(ls->t.token) || ls->t.token == ';')
+ first = nret = 0; /* return no values */
+ else {
+ nret = explist1(ls, &e); /* optional return values */
+ if (e.k == VCALL) {
+ luaK_setcallreturns(fs, &e, LUA_MULTRET);
+ if (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_codeABC(fs, OP_RETURN, first, nret+1, 0);
}
static void breakstat (LexState *ls) {
/* stat -> BREAK [NAME] */
FuncState *fs = ls->fs;
- int currentlevel = fs->stacklevel;
- Breaklabel *bl = fs->bl;
- if (!bl)
- luaK_error(ls, "no loop to break");
+ BlockCnt *bl = fs->bl;
+ int upval = 0;
next(ls); /* skip BREAK */
- luaK_adjuststack(fs, currentlevel - bl->stacklevel);
+ 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));
- /* correct stack for compiler and symbolic execution */
- luaK_adjuststack(fs, bl->stacklevel - currentlevel);
}
-static int stat (LexState *ls) {
+static int statement (LexState *ls) {
int line = ls->linenumber; /* may be needed for error messages */
switch (ls->t.token) {
case TK_IF: { /* stat -> ifstat */
@@ -1044,16 +1285,16 @@ static int stat (LexState *ls) {
repeatstat(ls, line);
return 0;
}
- case TK_FUNCTION: { /* stat -> funcstat */
- funcstat(ls, line);
+ case TK_FUNCTION: {
+ funcstat(ls, line); /* stat -> funcstat */
return 0;
}
case TK_LOCAL: { /* stat -> localstat */
- localstat(ls);
- return 0;
- }
- case TK_NAME: case '%': { /* stat -> namestat */
- namestat(ls);
+ next(ls); /* skip LOCAL */
+ if (testnext(ls, TK_FUNCTION)) /* local function? */
+ localfunc(ls);
+ else
+ localstat(ls);
return 0;
}
case TK_RETURN: { /* stat -> retstat */
@@ -1065,60 +1306,24 @@ static int stat (LexState *ls) {
return 1; /* must be last statement */
}
default: {
- luaK_error(ls, "<statement> expected");
+ exprstat(ls);
return 0; /* to avoid warnings */
}
}
}
-static void parlist (LexState *ls) {
- /* parlist -> [ param { ',' param } ] */
- int nparams = 0;
- int dots = 0;
- if (ls->t.token != ')') { /* is `parlist' not empty? */
- do {
- switch (ls->t.token) {
- case TK_DOTS: next(ls); dots = 1; break;
- case TK_NAME: new_localvar(ls, str_checkname(ls), nparams++); break;
- default: luaK_error(ls, "<name> or `...' expected");
- }
- } while (!dots && optional(ls, ','));
- }
- code_params(ls, nparams, dots);
-}
-
-
-static void body (LexState *ls, int needself, int line) {
- /* body -> '(' parlist ')' chunk END */
- FuncState new_fs;
- open_func(ls, &new_fs);
- new_fs.f->lineDefined = line;
- check(ls, '(');
- if (needself) {
- new_localvarstr(ls, "self", 0);
- adjustlocalvars(ls, 1);
- }
- parlist(ls);
- check(ls, ')');
- chunk(ls);
- check_match(ls, TK_END, TK_FUNCTION, line);
- close_func(ls);
- pushclosure(ls, &new_fs);
-}
-
-
-/* }====================================================================== */
-
-
static void chunk (LexState *ls) {
- /* chunk -> { stat [';'] } */
+ /* chunk -> { stat [`;'] } */
int islast = 0;
+ enterlevel(ls);
while (!islast && !block_follow(ls->t.token)) {
- islast = stat(ls);
- optional(ls, ';');
- LUA_ASSERT(ls->fs->stacklevel == ls->fs->nactloc,
- "stack size != # local vars");
+ islast = statement(ls);
+ testnext(ls, ';');
+ lua_assert(ls->fs->freereg >= ls->fs->nactvar);
+ ls->fs->freereg = ls->fs->nactvar; /* free registers */
}
+ leavelevel(ls);
}
+/* }====================================================================== */
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