commit 5894ca7b95d7fb05f1e93ee77e849a8d816d1c6d
parent abf8b1cd4a798fada026b4046e9dbc08791963f2
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Mon, 30 Dec 2024 16:53:24 -0300
Scanner doesn't need to anchor reserved words
Diffstat:
2 files changed, 20 insertions(+), 12 deletions(-)
diff --git a/llex.c b/llex.c
@@ -127,21 +127,20 @@ l_noret luaX_syntaxerror (LexState *ls, const char *msg) {
/*
-** Creates a new string and anchors it in scanner's table so that it
-** will not be collected until the end of the compilation; by that time
-** it should be anchored somewhere. It also internalizes long strings,
-** ensuring there is only one copy of each unique string.
+** Anchors a string in scanner's table so that it will not be collected
+** until the end of the compilation; by that time it should be anchored
+** somewhere. It also internalizes long strings, ensuring there is only
+** one copy of each unique string.
*/
-TString *luaX_newstring (LexState *ls, const char *str, size_t l) {
+static TString *anchorstr (LexState *ls, TString *ts) {
lua_State *L = ls->L;
- TString *ts = luaS_newlstr(L, str, l); /* create new string */
TValue oldts;
int tag = luaH_getstr(ls->h, ts, &oldts);
if (!tagisempty(tag)) /* string already present? */
return tsvalue(&oldts); /* use stored value */
else { /* create a new entry */
TValue *stv = s2v(L->top.p++); /* reserve stack space for string */
- setsvalue(L, stv, ts); /* temporarily anchor the string */
+ setsvalue(L, stv, ts); /* push (anchor) the string on the stack */
luaH_set(L, ls->h, stv, stv); /* t[string] = string */
/* table is not a metatable, so it does not need to invalidate cache */
luaC_checkGC(L);
@@ -152,6 +151,14 @@ TString *luaX_newstring (LexState *ls, const char *str, size_t l) {
/*
+** Creates a new string and anchors it in scanner's table.
+*/
+TString *luaX_newstring (LexState *ls, const char *str, size_t l) {
+ return anchorstr(ls, luaS_newlstr(ls->L, str, l));
+}
+
+
+/*
** increment line number and skips newline sequence (any of
** \n, \r, \n\r, or \r\n)
*/
@@ -544,12 +551,13 @@ static int llex (LexState *ls, SemInfo *seminfo) {
do {
save_and_next(ls);
} while (lislalnum(ls->current));
- ts = luaX_newstring(ls, luaZ_buffer(ls->buff),
- luaZ_bufflen(ls->buff));
- seminfo->ts = ts;
- if (isreserved(ts)) /* reserved word? */
+ /* find or create string */
+ ts = luaS_newlstr(ls->L, luaZ_buffer(ls->buff),
+ luaZ_bufflen(ls->buff));
+ if (isreserved(ts)) /* reserved word? */
return ts->extra - 1 + FIRST_RESERVED;
else {
+ seminfo->ts = anchorstr(ls, ts);
return TK_NAME;
}
}
diff --git a/lstring.h b/lstring.h
@@ -45,7 +45,7 @@
/*
** test whether a string is a reserved word
*/
-#define isreserved(s) ((s)->tt == LUA_VSHRSTR && (s)->extra > 0)
+#define isreserved(s) (strisshr(s) && (s)->extra > 0)
/*