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);
}
/*
** Create a jump instruction and return its position, so its destination
** can be fixed later (with 'fixjump'). If there are jumps to
** this position (kept in 'jpc'), link them all together so that
** 'patchlistaux' will fix all them directly to the final destination.
*/
int luaK_jump (FuncState *fs) {
int jpc = fs->jpc; /* save list of jumps to here */
int j;
fs->jpc = NO_JUMP; /* no more jumps to here */
j = luaK_codeAsBx(fs, OP_JMP, 0, NO_JUMP);
luaK_concat(fs, &j, jpc); /* keep them on hold */
return j;
}
int FuncState::luaK_jump (/*FuncState *fs*/) {
int jpc = this->jpc; /* save list of jumps to here */
int j;
this->jpc = NO_JUMP;
j = luaK_codeAsBx(OP_JMP, 0, NO_JUMP);
luaK_concat(&j, jpc); /* keep them on hold */
return j;
}
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 forlist (LexState *ls, TString *indexname) {
/* 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);
}
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);
}
