#define lparser_c
#define LUA_CORE
#include "lprefix.h"
#include <string.h>
#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 MAXVARS 200
#define hasmultret(k) ((k) == VCALL || (k) == VVARARG)
#define eqstr(a,b) ((a) == (b))
typedef struct BlockCnt {
struct BlockCnt *previous;
int firstlabel;
int firstgoto;
lu_byte nactvar;
lu_byte upval;
lu_byte isloop;
} BlockCnt;
static void statement (LexState *ls);
static void expr (LexState *ls, expdesc *v);
static l_noret semerror (LexState *ls, const char *msg) {
ls->t.token = 0;
luaX_syntaxerror(ls, msg);
}
static l_noret error_expected (LexState *ls, int token) {
luaX_syntaxerror(ls,
luaO_pushfstring(ls->L, "%s expected", luaX_token2str(ls, token)));
}
static l_noret errorlimit (FuncState *fs, int limit, const char *what) {
lua_State *L = fs->ls->L;
const char *msg;
int line = fs->f->linedefined;
const char *where = (line == 0)
? "main function"
: luaO_pushfstring(L, "function at line %d", line);
msg = luaO_pushfstring(L, "too many %s (limit is %d) in %s",
what, limit, where);
luaX_syntaxerror(fs->ls, msg);
}
static void checklimit (FuncState *fs, int v, int l, const char *what) {
if (v > l) errorlimit(fs, l, what);
}
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,
"%s expected (to close %s 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.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, "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++;
}
static void new_localvar (LexState *ls, TString *name) {
FuncState *fs = ls->fs;
Dyndata *dyd = ls->dyd;
int reg = registerlocalvar(ls, name);
checklimit(fs, dyd->actvar.n + 1 - fs->firstlocal,
MAXVARS, "local variables");
luaM_growvector(ls->L, dyd->actvar.arr, dyd->actvar.n + 1,
dyd->actvar.size, Vardesc, MAX_INT, "local variables");
dyd->actvar.arr[dyd->actvar.n++].idx = cast(short, reg);
}
static void new_localvarliteral_ (LexState *ls, const char *name, size_t sz) {
new_localvar(ls, luaX_newstring(ls, name, sz));
}
#define new_localvarliteral(ls,v) \
new_localvarliteral_(ls, "" v, (sizeof(v)/sizeof(char))-1)
static LocVar *getlocvar (FuncState *fs, int i) {
int idx = fs->ls->dyd->actvar.arr[fs->firstlocal + i].idx;
lua_assert(idx < fs->nlocvars);
return &fs->f->locvars[idx];
}
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 (FuncState *fs, int tolevel) {
fs->ls->dyd->actvar.n -= (fs->nactvar - tolevel);
while (fs->nactvar > tolevel)
getlocvar(fs, --fs->nactvar)->endpc = fs->pc;
}
static int searchupvalue (FuncState *fs, TString *name) {
int i;
Upvaldesc *up = fs->f->upvalues;
for (i = 0; i < fs->nups; i++) {
if (eqstr(up[i].name, name)) return i;
}
return -1;
}
static int newupvalue (FuncState *fs, TString *name, expdesc *v) {
Proto *f = fs->f;
int oldsize = f->sizeupvalues;
checklimit(fs, fs->nups + 1, MAXUPVAL, "upvalues");
luaM_growvector(fs->ls->L, f->upvalues, fs->nups, f->sizeupvalues,
Upvaldesc, MAXUPVAL, "upvalues");
while (oldsize < f->sizeupvalues) f->upvalues[oldsize++].name = NULL;
f->upvalues[fs->nups].instack = (v->k == VLOCAL);
f->upvalues[fs->nups].idx = cast_byte(v->u.info);
f->upvalues[fs->nups].name = name;
luaC_objbarrier(fs->ls->L, f, name);
return fs->nups++;
}
static int searchvar (FuncState *fs, TString *n) {
int i;
for (i = cast_int(fs->nactvar) - 1; i >= 0; i--) {
if (eqstr(n, getlocvar(fs, i)->varname))
return i;
}
return -1;
}
static void markupval (FuncState *fs, int level) {
BlockCnt *bl = fs->bl;
while (bl->nactvar > level) bl = bl->previous;
bl->upval = 1;
}
static int singlevaraux (FuncState *fs, TString *n, expdesc *var, int base) {
if (fs == NULL)
return VVOID;
else {
int v = searchvar(fs, n);
if (v >= 0) {
init_exp(var, VLOCAL, v);
if (!base)
markupval(fs, v);
return VLOCAL;
}
else {
int idx = searchupvalue(fs, n);
if (idx < 0) {
if (singlevaraux(fs->prev, n, var, 0) == VVOID)
return VVOID;
idx = newupvalue(fs, n, var);
}
init_exp(var, VUPVAL, idx);
return VUPVAL;
}
}
}
static void singlevar (LexState *ls, expdesc *var) {
TString *varname = str_checkname(ls);
FuncState *fs = ls->fs;
if (singlevaraux(fs, varname, var, 1) == VVOID) {
expdesc key;
singlevaraux(fs, ls->envn, var, 1);
lua_assert(var->k == VLOCAL || var->k == VUPVAL);
codestring(ls, &key, varname);
luaK_indexed(fs, var, &key);
}
}
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++;
if (extra < 0) extra = 0;
luaK_setreturns(fs, e, extra);
if (extra > 1) luaK_reserveregs(fs, extra-1);
}
else {
if (e->k != VVOID) luaK_exp2nextreg(fs, e);
if (extra > 0) {
int reg = fs->freereg;
luaK_reserveregs(fs, extra);
luaK_nil(fs, reg, extra);
}
}
}
static void enterlevel (LexState *ls) {
lua_State *L = ls->L;
++L->nCcalls;
checklimit(ls->fs, L->nCcalls, LUAI_MAXCCALLS, "C levels");
}
#define leavelevel(ls) ((ls)->L->nCcalls--)
static void closegoto (LexState *ls, int g, Labeldesc *label) {
int i;
FuncState *fs = ls->fs;
Labellist *gl = &ls->dyd->gt;
Labeldesc *gt = &gl->arr[g];
lua_assert(eqstr(gt->name, label->name));
if (gt->nactvar < label->nactvar) {
TString *vname = getlocvar(fs, gt->nactvar)->varname;
const char *msg = luaO_pushfstring(ls->L,
"<goto %s> at line %d jumps into the scope of local '%s'",
getstr(gt->name), gt->line, getstr(vname));
semerror(ls, msg);
}
luaK_patchlist(fs, gt->pc, label->pc);
for (i = g; i < gl->n - 1; i++)
gl->arr[i] = gl->arr[i + 1];
gl->n--;
}
static int findlabel (LexState *ls, int g) {
int i;
BlockCnt *bl = ls->fs->bl;
Dyndata *dyd = ls->dyd;
Labeldesc *gt = &dyd->gt.arr[g];
for (i = bl->firstlabel; i < dyd->label.n; i++) {
Labeldesc *lb = &dyd->label.arr[i];
if (eqstr(lb->name, gt->name)) {
if (gt->nactvar > lb->nactvar &&
(bl->upval || dyd->label.n > bl->firstlabel))
luaK_patchclose(ls->fs, gt->pc, lb->nactvar);
closegoto(ls, g, lb);
return 1;
}
}
return 0;
}
static int newlabelentry (LexState *ls, Labellist *l, TString *name,
int line, int pc) {
int n = l->n;
luaM_growvector(ls->L, l->arr, n, l->size,
Labeldesc, SHRT_MAX, "labels/gotos");
l->arr[n].name = name;
l->arr[n].line = line;
l->arr[n].nactvar = ls->fs->nactvar;
l->arr[n].pc = pc;
l->n = n + 1;
return n;
}
static void findgotos (LexState *ls, Labeldesc *lb) {
Labellist *gl = &ls->dyd->gt;
int i = ls->fs->bl->firstgoto;
while (i < gl->n) {
if (eqstr(gl->arr[i].name, lb->name))
closegoto(ls, i, lb);
else
i++;
}
}
static void movegotosout (FuncState *fs, BlockCnt *bl) {
int i = bl->firstgoto;
Labellist *gl = &fs->ls->dyd->gt;
while (i < gl->n) {
Labeldesc *gt = &gl->arr[i];
if (gt->nactvar > bl->nactvar) {
if (bl->upval)
luaK_patchclose(fs, gt->pc, bl->nactvar);
gt->nactvar = bl->nactvar;
}
if (!findlabel(fs->ls, i))
i++;
}
}
static void enterblock (FuncState *fs, BlockCnt *bl, lu_byte isloop) {
bl->isloop = isloop;
bl->nactvar = fs->nactvar;
bl->firstlabel = fs->ls->dyd->label.n;
bl->firstgoto = fs->ls->dyd->gt.n;
bl->upval = 0;
bl->previous = fs->bl;
fs->bl = bl;
lua_assert(fs->freereg == fs->nactvar);
}
static void breaklabel (LexState *ls) {
TString *n = luaS_new(ls->L, "break");
int l = newlabelentry(ls, &ls->dyd->label, n, 0, ls->fs->pc);
findgotos(ls, &ls->dyd->label.arr[l]);
}
static l_noret undefgoto (LexState *ls, Labeldesc *gt) {
const char *msg = isreserved(gt->name)
? "<%s> at line %d not inside a loop"
: "no visible label '%s' for <goto> at line %d";
msg = luaO_pushfstring(ls->L, msg, getstr(gt->name), gt->line);
semerror(ls, msg);
}
static void leaveblock (FuncState *fs) {
BlockCnt *bl = fs->bl;
LexState *ls = fs->ls;
if (bl->previous && bl->upval) {
int j = luaK_jump(fs);
luaK_patchclose(fs, j, bl->nactvar);
luaK_patchtohere(fs, j);
}
if (bl->isloop)
breaklabel(ls);
fs->bl = bl->previous;
removevars(fs, bl->nactvar);
lua_assert(bl->nactvar == fs->nactvar);
fs->freereg = fs->nactvar;
ls->dyd->label.n = bl->firstlabel;
if (bl->previous)
movegotosout(fs, bl);
else if (bl->firstgoto < ls->dyd->gt.n)
undefgoto(ls, &ls->dyd->gt.arr[bl->firstgoto]);
}
static Proto *addprototype (LexState *ls) {
Proto *clp;
lua_State *L = ls->L;
FuncState *fs = ls->fs;
Proto *f = fs->f;
if (fs->np >= f->sizep) {
int oldsize = f->sizep;
luaM_growvector(L, f->p, fs->np, f->sizep, Proto *, MAXARG_Bx, "functions");
while (oldsize < f->sizep) f->p[oldsize++] = NULL;
}
f->p[fs->np++] = clp = luaF_newproto(L);
luaC_objbarrier(L, f, clp);
return clp;
}
static void codeclosure (LexState *ls, expdesc *v) {
FuncState *fs = ls->fs->prev;
init_exp(v, VRELOCABLE, luaK_codeABx(fs, OP_CLOSURE, 0, fs->np - 1));
luaK_exp2nextreg(fs, v);
}
static void open_func (LexState *ls, FuncState *fs, BlockCnt *bl) {
Proto *f;
fs->prev = ls->fs;
fs->ls = ls;
ls->fs = fs;
fs->pc = 0;
fs->lasttarget = 0;
fs->jpc = NO_JUMP;
fs->freereg = 0;
fs->nk = 0;
fs->np = 0;
fs->nups = 0;
fs->nlocvars = 0;
fs->nactvar = 0;
fs->firstlocal = ls->dyd->actvar.n;
fs->bl = NULL;
f = fs->f;
f->source = ls->source;
f->maxstacksize = 2;
enterblock(fs, bl, 0);
}
static void close_func (LexState *ls) {
lua_State *L = ls->L;
FuncState *fs = ls->fs;
Proto *f = fs->f;
luaK_ret(fs, 0, 0);
leaveblock(fs);
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, fs->nups, Upvaldesc);
f->sizeupvalues = fs->nups;
lua_assert(fs->bl == NULL);
ls->fs = fs->prev;
luaC_checkGC(L);
}
static int block_follow (LexState *ls, int withuntil) {
switch (ls->t.token) {
case TK_ELSE: case TK_ELSEIF:
case TK_END: case TK_EOS:
return 1;
case TK_UNTIL: return withuntil;
default: return 0;
}
}
static void statlist (LexState *ls) {
while (!block_follow(ls, 1)) {
if (ls->t.token == TK_RETURN) {
statement(ls);
return;
}
statement(ls);
}
}
static void fieldsel (LexState *ls, expdesc *v) {
FuncState *fs = ls->fs;
expdesc key;
luaK_exp2anyregup(fs, v);
luaX_next(ls);
checkname(ls, &key);
luaK_indexed(fs, v, &key);
}
static void yindex (LexState *ls, expdesc *v) {
luaX_next(ls);
expr(ls, v);
luaK_exp2val(ls->fs, v);
checknext(ls, ']');
}
struct ConsControl {
expdesc v;
expdesc *t;
int nh;
int na;
int tostore;
};
static void recfield (LexState *ls, struct ConsControl *cc) {
FuncState *fs = ls->fs;
int reg = ls->fs->freereg;
expdesc key, val;
int rkkey;
if (ls->t.token == TK_NAME) {
checklimit(fs, cc->nh, MAX_INT, "items in a constructor");
checkname(ls, &key);
}
else
yindex(ls, &key);
cc->nh++;
checknext(ls, '=');
rkkey = luaK_exp2RK(fs, &key);
expr(ls, &val);
luaK_codeABC(fs, OP_SETTABLE, cc->t->u.info, rkkey, luaK_exp2RK(fs, &val));
fs->freereg = reg;
}
static void closelistfield (FuncState *fs, struct ConsControl *cc) {
if (cc->v.k == VVOID) return;
luaK_exp2nextreg(fs, &cc->v);
cc->v.k = VVOID;
if (cc->tostore == LFIELDS_PER_FLUSH) {
luaK_setlist(fs, cc->t->u.info, cc->na, cc->tostore);
cc->tostore = 0;
}
}
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.info, cc->na, LUA_MULTRET);
cc->na--;
}
else {
if (cc->v.k != VVOID)
luaK_exp2nextreg(fs, &cc->v);
luaK_setlist(fs, cc->t->u.info, cc->na, cc->tostore);
}
}
static void listfield (LexState *ls, struct ConsControl *cc) {
expr(ls, &cc->v);
checklimit(ls->fs, cc->na, MAX_INT, "items in a constructor");
cc->na++;
cc->tostore++;
}
static void field (LexState *ls, struct ConsControl *cc) {
switch(ls->t.token) {
case TK_NAME: {
if (luaX_lookahead(ls) != '=')
listfield(ls, cc);
else
recfield(ls, cc);
break;
}
case '[': {
recfield(ls, cc);
break;
}
default: {
listfield(ls, cc);
break;
}
}
}
static void constructor (LexState *ls, expdesc *t) {
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);
luaK_exp2nextreg(ls->fs, t);
checknext(ls, '{');
do {
lua_assert(cc.v.k == VVOID || cc.tostore > 0);
if (ls->t.token == '}') break;
closelistfield(fs, &cc);
field(ls, &cc);
} while (testnext(ls, ',') || testnext(ls, ';'));
check_match(ls, '}', '{', line);
lastlistfield(fs, &cc);
SETARG_B(fs->f->code[pc], luaO_int2fb(cc.na));
SETARG_C(fs->f->code[pc], luaO_int2fb(cc.nh));
}
static void parlist (LexState *ls) {
FuncState *fs = ls->fs;
Proto *f = fs->f;
int nparams = 0;
f->is_vararg = 0;
if (ls->t.token != ')') {
do {
switch (ls->t.token) {
case TK_NAME: {
new_localvar(ls, str_checkname(ls));
nparams++;
break;
}
case TK_DOTS: {
luaX_next(ls);
f->is_vararg = 1;
break;
}
default: luaX_syntaxerror(ls, "<name> or '...' expected");
}
} while (!f->is_vararg && testnext(ls, ','));
}
adjustlocalvars(ls, nparams);
f->numparams = cast_byte(fs->nactvar);
luaK_reserveregs(fs, fs->nactvar);
}
static void body (LexState *ls, expdesc *e, int ismethod, int line) {
FuncState new_fs;
BlockCnt bl;
new_fs.f = addprototype(ls);
new_fs.f->linedefined = line;
open_func(ls, &new_fs, &bl);
checknext(ls, '(');
if (ismethod) {
new_localvarliteral(ls, "self");
adjustlocalvars(ls, 1);
}
parlist(ls);
checknext(ls, ')');
statlist(ls);
new_fs.f->lastlinedefined = ls->linenumber;
check_match(ls, TK_END, TK_FUNCTION, line);
codeclosure(ls, e);
close_func(ls);
}
static int explist (LexState *ls, expdesc *v) {
int n = 1;
expr(ls, v);
while (testnext(ls, ',')) {
luaK_exp2nextreg(ls->fs, v);
expr(ls, v);
n++;
}
return n;
}
static void funcargs (LexState *ls, expdesc *f, int line) {
FuncState *fs = ls->fs;
expdesc args;
int base, nparams;
switch (ls->t.token) {
case '(': {
luaX_next(ls);
if (ls->t.token == ')')
args.k = VVOID;
else {
explist(ls, &args);
luaK_setmultret(fs, &args);
}
check_match(ls, ')', '(', line);
break;
}
case '{': {
constructor(ls, &args);
break;
}
case TK_STRING: {
codestring(ls, &args, ls->t.seminfo.ts);
luaX_next(ls);
break;
}
default: {
luaX_syntaxerror(ls, "function arguments expected");
}
}
lua_assert(f->k == VNONRELOC);
base = f->u.info;
if (hasmultret(args.k))
nparams = LUA_MULTRET;
else {
if (args.k != VVOID)
luaK_exp2nextreg(fs, &args);
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;
}
static void primaryexp (LexState *ls, expdesc *v) {
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");
}
}
}
static void suffixedexp (LexState *ls, expdesc *v) {
FuncState *fs = ls->fs;
int line = ls->linenumber;
primaryexp(ls, v);
for (;;) {
switch (ls->t.token) {
case '.': {
fieldsel(ls, v);
break;
}
case '[': {
expdesc key;
luaK_exp2anyregup(fs, v);
yindex(ls, &key);
luaK_indexed(fs, v, &key);
break;
}
case ':': {
expdesc key;
luaX_next(ls);
checkname(ls, &key);
luaK_self(fs, v, &key);
funcargs(ls, v, line);
break;
}
case '(': case TK_STRING: case '{': {
luaK_exp2nextreg(fs, v);
funcargs(ls, v, line);
break;
}
default: return;
}
}
}
static void simpleexp (LexState *ls, expdesc *v) {
switch (ls->t.token) {
case TK_FLT: {
init_exp(v, VKFLT, 0);
v->u.nval = ls->t.seminfo.r;
break;
}
case TK_INT: {
init_exp(v, VKINT, 0);
v->u.ival = ls->t.seminfo.i;
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: {
FuncState *fs = ls->fs;
check_condition(ls, fs->f->is_vararg,
"cannot use '...' outside a vararg function");
init_exp(v, VVARARG, luaK_codeABC(fs, OP_VARARG, 0, 1, 0));
break;
}
case '{': {
constructor(ls, v);
return;
}
case TK_FUNCTION: {
luaX_next(ls);
body(ls, v, 0, ls->linenumber);
return;
}
default: {
suffixedexp(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_BNOT;
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_MOD;
case '^': return OPR_POW;
case '/': return OPR_DIV;
case TK_IDIV: return OPR_IDIV;
case '&': return OPR_BAND;
case '|': return OPR_BOR;
case '~': return OPR_BXOR;
case TK_SHL: return OPR_SHL;
case TK_SHR: return OPR_SHR;
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;
lu_byte right;
} priority[] = {
{10, 10}, {10, 10},
{11, 11}, {11, 11},
{14, 13},
{11, 11}, {11, 11},
{6, 6}, {4, 4}, {5, 5},
{7, 7}, {7, 7},
{9, 8},
{3, 3}, {3, 3}, {3, 3},
{3, 3}, {3, 3}, {3, 3},
{2, 2}, {1, 1}
};
#define UNARY_PRIORITY 12
static BinOpr subexpr (LexState *ls, expdesc *v, int limit) {
BinOpr op;
UnOpr uop;
enterlevel(ls);
uop = getunopr(ls->t.token);
if (uop != OPR_NOUNOPR) {
int line = ls->linenumber;
luaX_next(ls);
subexpr(ls, v, UNARY_PRIORITY);
luaK_prefix(ls->fs, uop, v, line);
}
else simpleexp(ls, v);
op = getbinopr(ls->t.token);
while (op != OPR_NOBINOPR && priority[op].left > limit) {
expdesc v2;
BinOpr nextop;
int line = ls->linenumber;
luaX_next(ls);
luaK_infix(ls->fs, op, v);
nextop = subexpr(ls, &v2, priority[op].right);
luaK_posfix(ls->fs, op, v, &v2, line);
op = nextop;
}
leavelevel(ls);
return op;
}
static void expr (LexState *ls, expdesc *v) {
subexpr(ls, v, 0);
}
static void block (LexState *ls) {
FuncState *fs = ls->fs;
BlockCnt bl;
enterblock(fs, &bl, 0);
statlist(ls);
leaveblock(fs);
}
struct LHS_assign {
struct LHS_assign *prev;
expdesc v;
};
static void check_conflict (LexState *ls, struct LHS_assign *lh, expdesc *v) {
FuncState *fs = ls->fs;
int extra = fs->freereg;
int conflict = 0;
for (; lh; lh = lh->prev) {
if (lh->v.k == VINDEXED) {
if (lh->v.u.ind.vt == v->k && lh->v.u.ind.t == v->u.info) {
conflict = 1;
lh->v.u.ind.vt = VLOCAL;
lh->v.u.ind.t = extra;
}
if (v->k == VLOCAL && lh->v.u.ind.idx == v->u.info) {
conflict = 1;
lh->v.u.ind.idx = extra;
}
}
}
if (conflict) {
OpCode op = (v->k == VLOCAL) ? OP_MOVE : OP_GETUPVAL;
luaK_codeABC(fs, op, extra, v->u.info, 0);
luaK_reserveregs(fs, 1);
}
}
static void assignment (LexState *ls, struct LHS_assign *lh, int nvars) {
expdesc e;
check_condition(ls, vkisvar(lh->v.k), "syntax error");
if (testnext(ls, ',')) {
struct LHS_assign nv;
nv.prev = lh;
suffixedexp(ls, &nv.v);
if (nv.v.k != VINDEXED)
check_conflict(ls, lh, &nv.v);
checklimit(ls->fs, nvars + ls->L->nCcalls, LUAI_MAXCCALLS,
"C levels");
assignment(ls, &nv, nvars+1);
}
else {
int nexps;
checknext(ls, '=');
nexps = explist(ls, &e);
if (nexps != nvars) {
adjust_assign(ls, nvars, nexps, &e);
if (nexps > nvars)
ls->fs->freereg -= nexps - nvars;
}
else {
luaK_setoneret(ls->fs, &e);
luaK_storevar(ls->fs, &lh->v, &e);
return;
}
}
init_exp(&e, VNONRELOC, ls->fs->freereg-1);
luaK_storevar(ls->fs, &lh->v, &e);
}
static int cond (LexState *ls) {
expdesc v;
expr(ls, &v);
if (v.k == VNIL) v.k = VFALSE;
luaK_goiftrue(ls->fs, &v);
return v.f;
}
static void gotostat (LexState *ls, int pc) {
int line = ls->linenumber;
TString *label;
int g;
if (testnext(ls, TK_GOTO))
label = str_checkname(ls);
else {
luaX_next(ls);
label = luaS_new(ls->L, "break");
}
g = newlabelentry(ls, &ls->dyd->gt, label, line, pc);
findlabel(ls, g);
}
static void checkrepeated (FuncState *fs, Labellist *ll, TString *label) {
int i;
for (i = fs->bl->firstlabel; i < ll->n; i++) {
if (eqstr(label, ll->arr[i].name)) {
const char *msg = luaO_pushfstring(fs->ls->L,
"label '%s' already defined on line %d",
getstr(label), ll->arr[i].line);
semerror(fs->ls, msg);
}
}
}
static void skipnoopstat (LexState *ls) {
while (ls->t.token == ';' || ls->t.token == TK_DBCOLON)
statement(ls);
}
static void labelstat (LexState *ls, TString *label, int line) {
FuncState *fs = ls->fs;
Labellist *ll = &ls->dyd->label;
int l;
checkrepeated(fs, ll, label);
checknext(ls, TK_DBCOLON);
l = newlabelentry(ls, ll, label, line, fs->pc);
skipnoopstat(ls);
if (block_follow(ls, 0)) {
ll->arr[l].nactvar = fs->bl->nactvar;
}
findgotos(ls, &ll->arr[l]);
}
static void whilestat (LexState *ls, int line) {
FuncState *fs = ls->fs;
int whileinit;
int condexit;
BlockCnt bl;
luaX_next(ls);
whileinit = luaK_getlabel(fs);
condexit = cond(ls);
enterblock(fs, &bl, 1);
checknext(ls, TK_DO);
block(ls);
luaK_jumpto(fs, whileinit);
check_match(ls, TK_END, TK_WHILE, line);
leaveblock(fs);
luaK_patchtohere(fs, condexit);
}
static void repeatstat (LexState *ls, int line) {
int condexit;
FuncState *fs = ls->fs;
int repeat_init = luaK_getlabel(fs);
BlockCnt bl1, bl2;
enterblock(fs, &bl1, 1);
enterblock(fs, &bl2, 0);
luaX_next(ls);
statlist(ls);
check_match(ls, TK_UNTIL, TK_REPEAT, line);
condexit = cond(ls);
if (bl2.upval)
luaK_patchclose(fs, condexit, bl2.nactvar);
leaveblock(fs);
luaK_patchlist(fs, condexit, repeat_init);
leaveblock(fs);
}
static int exp1 (LexState *ls) {
expdesc e;
int reg;
expr(ls, &e);
luaK_exp2nextreg(ls->fs, &e);
lua_assert(e.k == VNONRELOC);
reg = e.u.info;
return reg;
}
static void forbody (LexState *ls, int base, int line, int nvars, int isnum) {
BlockCnt bl;
FuncState *fs = ls->fs;
int prep, endfor;
adjustlocalvars(ls, 3);
checknext(ls, TK_DO);
prep = isnum ? luaK_codeAsBx(fs, OP_FORPREP, base, NO_JUMP) : luaK_jump(fs);
enterblock(fs, &bl, 0);
adjustlocalvars(ls, nvars);
luaK_reserveregs(fs, nvars);
block(ls);
leaveblock(fs);
luaK_patchtohere(fs, prep);
if (isnum)
endfor = luaK_codeAsBx(fs, OP_FORLOOP, base, NO_JUMP);
else {
luaK_codeABC(fs, OP_TFORCALL, base, 0, nvars);
luaK_fixline(fs, line);
endfor = luaK_codeAsBx(fs, OP_TFORLOOP, base + 2, NO_JUMP);
}
luaK_patchlist(fs, endfor, prep + 1);
luaK_fixline(fs, line);
}
static void fornum (LexState *ls, TString *varname, int line) {
FuncState *fs = ls->fs;
int base = fs->freereg;
new_localvarliteral(ls, "(for index)");
new_localvarliteral(ls, "(for limit)");
new_localvarliteral(ls, "(for step)");
new_localvar(ls, varname);
checknext(ls, '=');
exp1(ls);
checknext(ls, ',');
exp1(ls);
if (testnext(ls, ','))
exp1(ls);
else {
luaK_codek(fs, fs->freereg, luaK_intK(fs, 1));
luaK_reserveregs(fs, 1);
}
forbody(ls, base, line, 1, 1);
}
static void forlist (LexState *ls, TString *indexname) {
FuncState *fs = ls->fs;
expdesc e;
int nvars = 4;
int line;
int base = fs->freereg;
new_localvarliteral(ls, "(for generator)");
new_localvarliteral(ls, "(for state)");
new_localvarliteral(ls, "(for control)");
new_localvar(ls, indexname);
while (testnext(ls, ',')) {
new_localvar(ls, str_checkname(ls));
nvars++;
}
checknext(ls, TK_IN);
line = ls->linenumber;
adjust_assign(ls, 3, explist(ls, &e), &e);
luaK_checkstack(fs, 3);
forbody(ls, base, line, nvars - 3, 0);
}
static void forstat (LexState *ls, int line) {
FuncState *fs = ls->fs;
TString *varname;
BlockCnt bl;
enterblock(fs, &bl, 1);
luaX_next(ls);
varname = str_checkname(ls);
switch (ls->t.token) {
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);
leaveblock(fs);
}
static void test_then_block (LexState *ls, int *escapelist) {
BlockCnt bl;
FuncState *fs = ls->fs;
expdesc v;
int jf;
luaX_next(ls);
expr(ls, &v);
checknext(ls, TK_THEN);
if (ls->t.token == TK_GOTO || ls->t.token == TK_BREAK) {
luaK_goiffalse(ls->fs, &v);
enterblock(fs, &bl, 0);
gotostat(ls, v.t);
skipnoopstat(ls);
if (block_follow(ls, 0)) {
leaveblock(fs);
return;
}
else
jf = luaK_jump(fs);
}
else {
luaK_goiftrue(ls->fs, &v);
enterblock(fs, &bl, 0);
jf = v.f;
}
statlist(ls);
leaveblock(fs);
if (ls->t.token == TK_ELSE ||
ls->t.token == TK_ELSEIF)
luaK_concat(fs, escapelist, luaK_jump(fs));
luaK_patchtohere(fs, jf);
}
static void ifstat (LexState *ls, int line) {
FuncState *fs = ls->fs;
int escapelist = NO_JUMP;
test_then_block(ls, &escapelist);
while (ls->t.token == TK_ELSEIF)
test_then_block(ls, &escapelist);
if (testnext(ls, TK_ELSE))
block(ls);
check_match(ls, TK_END, TK_IF, line);
luaK_patchtohere(fs, escapelist);
}
static void localfunc (LexState *ls) {
expdesc b;
FuncState *fs = ls->fs;
new_localvar(ls, str_checkname(ls));
adjustlocalvars(ls, 1);
body(ls, &b, 0, ls->linenumber);
getlocvar(fs, b.u.info)->startpc = fs->pc;
}
static void localstat (LexState *ls) {
int nvars = 0;
int nexps;
expdesc e;
do {
new_localvar(ls, str_checkname(ls));
nvars++;
} while (testnext(ls, ','));
if (testnext(ls, '='))
nexps = explist(ls, &e);
else {
e.k = VVOID;
nexps = 0;
}
adjust_assign(ls, nvars, nexps, &e);
adjustlocalvars(ls, nvars);
}
static int funcname (LexState *ls, expdesc *v) {
int ismethod = 0;
singlevar(ls, v);
while (ls->t.token == '.')
fieldsel(ls, v);
if (ls->t.token == ':') {
ismethod = 1;
fieldsel(ls, v);
}
return ismethod;
}
static void funcstat (LexState *ls, int line) {
int ismethod;
expdesc v, b;
luaX_next(ls);
ismethod = funcname(ls, &v);
body(ls, &b, ismethod, line);
luaK_storevar(ls->fs, &v, &b);
luaK_fixline(ls->fs, line);
}
static void exprstat (LexState *ls) {
FuncState *fs = ls->fs;
struct LHS_assign v;
suffixedexp(ls, &v.v);
if (ls->t.token == '=' || ls->t.token == ',') {
v.prev = NULL;
assignment(ls, &v, 1);
}
else {
check_condition(ls, v.v.k == VCALL, "syntax error");
SETARG_C(getcode(fs, &v.v), 1);
}
}
static void retstat (LexState *ls) {
FuncState *fs = ls->fs;
expdesc e;
int first, nret;
if (block_follow(ls, 1) || ls->t.token == ';')
first = nret = 0;
else {
nret = explist(ls, &e);
if (hasmultret(e.k)) {
luaK_setmultret(fs, &e);
if (e.k == VCALL && nret == 1) {
SET_OPCODE(getcode(fs,&e), OP_TAILCALL);
lua_assert(GETARG_A(getcode(fs,&e)) == fs->nactvar);
}
first = fs->nactvar;
nret = LUA_MULTRET;
}
else {
if (nret == 1)
first = luaK_exp2anyreg(fs, &e);
else {
luaK_exp2nextreg(fs, &e);
first = fs->nactvar;
lua_assert(nret == fs->freereg - first);
}
}
}
luaK_ret(fs, first, nret);
testnext(ls, ';');
}
static void statement (LexState *ls) {
int line = ls->linenumber;
enterlevel(ls);
switch (ls->t.token) {
case ';': {
luaX_next(ls);
break;
}
case TK_IF: {
ifstat(ls, line);
break;
}
case TK_WHILE: {
whilestat(ls, line);
break;
}
case TK_DO: {
luaX_next(ls);
block(ls);
check_match(ls, TK_END, TK_DO, line);
break;
}
case TK_FOR: {
forstat(ls, line);
break;
}
case TK_REPEAT: {
repeatstat(ls, line);
break;
}
case TK_FUNCTION: {
funcstat(ls, line);
break;
}
case TK_LOCAL: {
luaX_next(ls);
if (testnext(ls, TK_FUNCTION))
localfunc(ls);
else
localstat(ls);
break;
}
case TK_DBCOLON: {
luaX_next(ls);
labelstat(ls, str_checkname(ls), line);
break;
}
case TK_RETURN: {
luaX_next(ls);
retstat(ls);
break;
}
case TK_BREAK:
case TK_GOTO: {
gotostat(ls, luaK_jump(ls->fs));
break;
}
default: {
exprstat(ls);
break;
}
}
lua_assert(ls->fs->f->maxstacksize >= ls->fs->freereg &&
ls->fs->freereg >= ls->fs->nactvar);
ls->fs->freereg = ls->fs->nactvar;
leavelevel(ls);
}
static void mainfunc (LexState *ls, FuncState *fs) {
BlockCnt bl;
expdesc v;
open_func(ls, fs, &bl);
fs->f->is_vararg = 1;
init_exp(&v, VLOCAL, 0);
newupvalue(fs, ls->envn, &v);
luaX_next(ls);
statlist(ls);
check(ls, TK_EOS);
close_func(ls);
}
LClosure *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff,
Dyndata *dyd, const char *name, int firstchar) {
LexState lexstate;
FuncState funcstate;
LClosure *cl = luaF_newLclosure(L, 1);
setclLvalue(L, L->top, cl);
incr_top(L);
lexstate.h = luaH_new(L);
sethvalue(L, L->top, lexstate.h);
incr_top(L);
funcstate.f = cl->p = luaF_newproto(L);
funcstate.f->source = luaS_new(L, name);
lua_assert(iswhite(funcstate.f));
lexstate.buff = buff;
lexstate.dyd = dyd;
dyd->actvar.n = dyd->gt.n = dyd->label.n = 0;
luaX_setinput(L, &lexstate, z, funcstate.f->source, firstchar);
mainfunc(&lexstate, &funcstate);
lua_assert(!funcstate.prev && funcstate.nups == 1 && !lexstate.fs);
lua_assert(dyd->actvar.n == 0 && dyd->gt.n == 0 && dyd->label.n == 0);
L->top--;
return cl;
}