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);
luaK_patchtohere(fs, bl1.continuelist);
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 void selectstat (LexState *ls, int line) {
/* selectstat -> CASE val1 OF val2 THEN block [OF valx THEN block [ELSE THEN block]] ESAC */
FuncState *fs = ls->fs;
BlockCnt bl;
int escapelist = NO_JUMP;
expdesc v;
luaX_next(ls); /* skip `case' */
enterblock(fs, &bl, 0); /* block to control variable scope */
expr(ls, &v);
checknext(ls, TK_OF);
casestat(ls, &v);
while (ls->t.token == TK_OF) {
luaK_concat(fs, &escapelist, luaK_jump(fs));
luaK_patchtohere(fs, v.f);
luaX_next(ls); /* skip OF */
casestat(ls, &v); /* OF val THEN block */
}
if (ls->t.token == TK_ELSE) {
luaK_concat(fs, &escapelist, luaK_jump(fs));
luaK_patchtohere(fs, v.f);
luaX_next(ls); /* skip ELSE */
block(ls); /* default part */
} else {
luaK_concat(fs, &escapelist, v.f);
}
luaK_patchtohere(fs, escapelist);
check_match(ls, TK_ESAC, TK_CASE, line);
leaveblock(fs);
}
static void forstat (LexState *ls, int line)
{
/* forstat -> FOR (fornum | forlist) END */
FuncState *fs = GetCurrentFuncState( ls );
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");
break;
}
check_match(ls, TK_END, TK_FOR, line);
leaveblock(fs); /* loop scope (`break' jumps to this point) */
}
static void forbody (LexState *ls, int base, int line, int nvars, int isnum)
{
/* forbody -> DO block */
BlockCnt bl;
FuncState *fs = GetCurrentFuncState( ls );
adjustlocalvars(ls, 3); /* control variables */
checknext(ls, TK_DO);
int 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);
int 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 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);
}
static void block (LexState *ls) {
/* block -> chunk */
FuncState *fs = ls->fs;
BlockCnt *pbl = (BlockCnt*)luaM_malloc(ls->L,sizeof(BlockCnt));
enterblock(fs, pbl, 0);
chunk(ls);
lua_assert(pbl->breaklist == NO_JUMP);
leaveblock(fs);
luaM_free(ls->L,pbl);
}
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);
#if LUA_EXT_CONTINUE
if (bl2.continuelist != NO_JUMP) {
int oldprohibition = fs->prohibitedloc;
luaK_patchtohere(fs, bl2.continuelist);
fs->prohibitedloc = bl2.continuepos;
condexit = cond(ls); /* read condition (inside scope block) */
fs->prohibitedloc = oldprohibition;
bl2.continuelist = NO_JUMP;
}
else {
condexit = cond(ls); /* read condition (inside scope block) */
}
#else
condexit = cond(ls); /* read condition (inside scope block) */
#endif /* LUA_EXT_CONTINUE */
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 void repeatstat (LexState *ls, int line) {
/* repeatstat -> REPEAT block UNTIL cond */
FuncState *fs = ls->fs;
int repeat_init = luaK_getlabel(fs);
expdesc v;
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.f, repeat_init);
leaveblock(fs);
}
static void forstat (LexState *ls, int line) {
/* forstat -> fornum | forlist */
FuncState *fs = ls->fs;
TString *varname;
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, 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 forbody (LexState *ls, int base, int line, int nvars, int isnum) {
BlockCnt bl;
FuncState *fs = ls->fs;
int prep, endfor;
adjustlocalvars(ls, nvars); /* scope for all variables */
check(ls, TK_DO);
enterblock(fs, &bl, 1); /* loop block */
prep = luaK_getlabel(fs);
block(ls);
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 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 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 whileinit, blockinit, expinit;
expdesc 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_patchtohere(fs, whileinit); /* initial jump jumps to here */
luaK_patchtohere(fs, bl.continuelist);
/* 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);
leaveblock(fs);
luaK_patchlist(fs, v.t, blockinit); /* true conditions go back to loop */
luaK_patchtohere(fs, v.f); /* false conditions finish the loop */
}
static void trystat (LexState *ls, int line) {
/* trystat -> TRY block CATCH err DO block END */
FuncState *fs = ls->fs;
BlockCnt bl;
int base, pc, escapelist = NO_JUMP;
luaX_next(ls);
enterblock(fs, &bl, 2); /* try block */
base = fs->freereg;
new_localvarliteral(ls, "(error obj)", 0);
adjustlocalvars(ls, 1); /* error object */
luaK_reserveregs(fs, 1);
pc = luaK_codeAsBx(fs, OP_TRY, base, NO_JUMP);
chunk(ls);
if (ls->t.token == TK_CATCH) {
TString *varname;
int errobj;
luaK_codeABC(fs, OP_EXITTRY, 0, 0, 0);
luaK_concat(fs, &escapelist, luaK_jump(fs));
SET_OPCODE(fs->f->code[pc], OP_TRYCATCH); /* change it to TRYCATCH */
luaK_patchtohere(fs, pc);
bl.isbreakable = 0;
// local err
luaX_next(ls); /* skip `catch' */
varname = str_checkname(ls); /* first variable name */
// do
checknext(ls, TK_DO);
errobj = fs->freereg;
new_localvar(ls, varname, 0);
adjustlocalvars(ls, 1);
luaK_reserveregs(fs, 1);
luaK_codeABC(fs, OP_MOVE, errobj, base, 0);
block(ls);
} else if (ls->t.token == TK_FINALLY) {
luaK_codeABC(fs, OP_EXITTRY, 0, 0, 0);
luaK_concat(fs, &escapelist, luaK_jump(fs));
SET_OPCODE(fs->f->code[pc], OP_TRYFIN); /* change it to TRYFIN */
luaK_patchtohere(fs, pc);
bl.isbreakable = 3;
luaX_next(ls); /* skip 'finally' */
block(ls);
luaK_codeABC(fs, OP_RETFIN, base, 0, 0); /* OP_ENDFIN jump to the return point */
} else {
luaK_codeABC(fs, OP_EXITTRY, 0, 0, 0);
luaK_concat(fs, &escapelist, pc);
}
leaveblock(fs);
luaK_patchtohere(fs, escapelist);
check_match(ls, TK_END, TK_TRY, line);
}