void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) {
switch (var->k) {
case VLOCAL: {
int e = luaK_exp2anyreg(fs, ex);
luaK_codeABC(fs, OP_SETLOCAL, e, var->u.info, 0);
break;
}
case VUPVAL: {
int e = luaK_exp2anyreg(fs, ex);
luaK_codeABC(fs, OP_SETUPVAL, e, var->u.info, 0);
break;
}
case VINDEXED: {
OpCode op = (var->u.ind.vt == VLOCAL) ? OP_SETTABLE : OP_SETTABUP;
int e = luaK_exp2RK(fs, ex);
luaK_codeABC(fs, op, var->u.ind.t, var->u.ind.idx, e);
break;
}
default: {
lua_assert(0); /* invalid var kind to store */
break;
}
}
freeexp(fs, ex);
}
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 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 void codearith (FuncState *fs, OpCode op,
expdesc *e1, expdesc *e2, int line) {
if (!constfolding(fs, op - OP_ADD + LUA_OPADD, e1, e2)) {
int o1, o2;
if (op == OP_UNM || op == OP_BNOT || op == OP_LEN) {
o2 = 0;
o1 = luaK_exp2anyreg(fs, e1); /* cannot operate on constants */
}
else { /* regular case (binary operators) */
o2 = luaK_exp2RK(fs, e2);
o1 = luaK_exp2RK(fs, e1);
}
if (o1 > o2) {
freeexp(fs, e1);
freeexp(fs, e2);
}
else {
freeexp(fs, e2);
freeexp(fs, e1);
}
e1->u.info = luaK_codeABC(fs, op, 0, o1, o2);
e1->k = VRELOCABLE;
luaK_fixline(fs, line);
}
}
int luaK_exp2RK (FuncState *fs, expdesc *e) {
luaK_exp2val(fs, e);
switch (e->k) {
case VTRUE:
case VFALSE:
case VNIL: {
if (fs->nk <= MAXINDEXRK) { /* constant fits in RK operand? */
e->u.info = (e->k == VNIL) ? nilK(fs) : boolK(fs, (e->k == VTRUE));
e->k = VK;
return RKASK(e->u.info);
}
else break;
}
case VKINT: {
e->u.info = luaK_intK(fs, e->u.ival);
e->k = VK;
goto vk;
}
case VKFLT: {
e->u.info = luaK_numberK(fs, e->u.nval);
e->k = VK;
/* go through */
}
case VK: {
vk:
if (e->u.info <= MAXINDEXRK) /* constant fits in argC? */
return RKASK(e->u.info);
else break;
}
default: break;
}
/* not a constant in the right range: put it in a register */
return luaK_exp2anyreg(fs, e);
}
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);
}
void luaK_self (FuncState *fs, expdesc *e, expdesc *key) {
int ereg;
luaK_exp2anyreg(fs, e);
ereg = e->u.info; /* register where 'e' was placed */
freeexp(fs, e);
e->u.info = fs->freereg; /* base register for op_self */
e->k = VNONRELOC;
luaK_reserveregs(fs, 2); /* function and 'self' produced by op_self */
luaK_codeABC(fs, OP_SELF, e->u.info, ereg, luaK_exp2RK(fs, key));
freeexp(fs, key);
}
static void retstat (LexState *ls) {
/* stat -> RETURN explist */
FuncState *fs = ls->fs;
BlockCnt *bl = fs->bl;
expdesc e;
int first, nret; /* registers with returned values */
int ret_in_try = 0;
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);
}
}
}
/* before return, we should exit all try-catch blocks */
while (bl) {
if (bl->isbreakable == 2) {
if (ret_in_try)
luaK_codeABC(fs, OP_EXITTRY, 0, 0, 0);
else {
ret_in_try = 1;
luaK_codeABC(fs, OP_EXITTRY, first, nret+1, 1); /* here we will save all return values */
}
} else if (bl->isbreakable == 3)
luaX_syntaxerror(ls, "can't return in _finally_ clause");
bl = bl->previous;
}
luaK_codeABC(fs, OP_RETURN, first, nret+1, ret_in_try);
}
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;
}
#if LUA_WIDESTRING
case '(': case TK_STRING: case TK_WSTRING: case '{': { /* funcargs */
#else
case '(': case TK_STRING: case '{': { /* funcargs */
#endif /* LUA_WIDESTRING */
luaK_exp2nextreg(fs, v);
funcargs(ls, v);
break;
}
default: return;
}
}
}
static void simpleexp (LexState *ls, expdesc *v) {
#if LUA_WIDESTRING
/* simpleexp -> NUMBER | STRING | WSTRING | NIL | true | false | ... |
constructor | FUNCTION body | primaryexp */
#else
/* simpleexp -> NUMBER | STRING | NIL | true | false | ... |
constructor | FUNCTION body | primaryexp */
#endif /* LUA_WIDESTRING */
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;
}
#if LUA_WIDESTRING
case TK_WSTRING: {
codewstring(ls, v, ls->t.seminfo.ts);
break;
}
#endif /* LUA_WIDESTRING */
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;
#if LUA_BITFIELD_OPS
case '&': return OPR_BAND;
case '|': return OPR_BOR;
case TK_XOR: return OPR_BXOR;
case TK_SHL: return OPR_BSHL;
case TK_SHR: return OPR_BSHR;
#endif /* LUA_BITFIELD_OPS */
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 */
#if LUA_BITFIELD_OPS
{8, 8}, {8, 8}, {8, 8}, {8, 8}, {8, 8}, /* bitwise operators */
#endif /* LUA_BITFIELD_OPS */
{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 */
}
void luaK_exp2val (FuncState *fs, expdesc *e) {
if (hasjumps(e))
luaK_exp2anyreg(fs, e);
else
luaK_dischargevars(fs, e);
}
void luaK_exp2anyregup (FuncState *fs, expdesc *e) {
if (e->k != VUPVAL || hasjumps(e))
luaK_exp2anyreg(fs, e);
}
