From 1c70983df1118ba3ab10719032712f199a844381 Mon Sep 17 00:00:00 2001
From: fesily <fesil@foxmail.com>
Date: Fri, 18 Aug 2023 16:19:15 +0800
Subject: [PATCH] add parser table hash patch

---
 src/lj_arch.h  | 12 ++++++++----
 src/lj_parse.c | 14 ++++++++++++++
 src/lj_str.c   |  6 +++++-
 src/lj_tab.c   | 26 ++++++++++++++++++++++++++
 src/lj_tab.h   |  3 +++
 5 files changed, 56 insertions(+), 5 deletions(-)

diff --git a/src/lj_arch.h b/src/lj_arch.h
index 35671072..e5bb63d9 100644
--- a/src/lj_arch.h
+++ b/src/lj_arch.h
@@ -760,10 +760,10 @@ extern void *LJ_WIN_LOADLIBA(const char *path);
 #endif
 
 #ifdef LJ_DS
-    #ifdef LUAJIT_SECURITY_STRHASH
-    #undef LUAJIT_SECURITY_STRHASH
-    #endif
-#define LUAJIT_SECURITY_STRHASH !LJ_DS
+#undef LUAJIT_SECURITY_STRHASH
+#undef LUAJIT_SECURITY_STRID
+#define LUAJIT_SECURITY_STRHASH 0
+#define LUAJIT_SECURITY_STRID 0
 #endif
 
 #ifndef LJ_DS_LOADBUFFER_PATCH
@@ -778,4 +778,8 @@ extern void *LJ_WIN_LOADLIBA(const char *path);
 #define LUA_COMPAT_GFIND LJ_DS
 #endif
 
+#ifndef LJ_DS_STR_HASH_PATCH
+#define LJ_DS_STR_HASH_PATCH LJ_DS
+#endif
+
 #endif
diff --git a/src/lj_parse.c b/src/lj_parse.c
index 675fd228..963ed491 100644
--- a/src/lj_parse.c
+++ b/src/lj_parse.c
@@ -1730,6 +1730,10 @@ static void expr_table(LexState *ls, ExpDesc *e)
   bcreg_reserve(fs, 1);
   freg++;
   lex_check(ls, '{');
+#if LJ_DS_PARSER_TABLE_PATCH
+  GCtab* tmp_t = lj_tab_new(fs->L, 0, 0);
+  int tmp_indx = 0;
+#endif
   while (ls->tok != '}') {
     ExpDesc key, val;
     vcall = 0;
@@ -1763,6 +1767,12 @@ static void expr_table(LexState *ls, ExpDesc *e)
       expr_kvalue(fs, &k, &key);
       v = lj_tab_set(fs->L, t, &k);
       lj_gc_anybarriert(fs->L, t);
+#if LJ_DS_PARSER_TABLE_PATCH
+      TValue* tmp_v = lj_tab_setint(fs->L, tmp_t, tmp_indx);
+      tmp_indx++;
+      lj_gc_anybarriert(fs->L, tmp_t);
+      copyTV(fs->L, tmp_v, &k);
+#endif
       if (expr_isk_nojump(&val)) {  /* Add const key/value to template table. */
 	expr_kvalue(fs, v, &val);
       } else {  /* Otherwise create dummy string key (avoids lj_tab_newkey). */
@@ -1811,6 +1821,10 @@ static void expr_table(LexState *ls, ExpDesc *e)
     if ((needarr && t->asize != narr) ||  hsize2hmask(nhash) != t->hmask) {
       lj_tab_resize(fs->L, t, narr, hsize2hbits(nhash));
     }
+    if (t->hmask) {
+      // rebuild hash 
+      lj_tab_rehash_bykeys(fs->L, t, tmp_t);
+    }
 #else
     if (needarr && t->asize < narr)
       lj_tab_reasize(fs->L, t, narr-1);
diff --git a/src/lj_str.c b/src/lj_str.c
index dbf555d5..5131ebb1 100644
--- a/src/lj_str.c
+++ b/src/lj_str.c
@@ -75,7 +75,7 @@ int lj_str_haspattern(GCstr *s)
 /* Keyed sparse ARX string hash. Constant time. */
 static StrHash hash_sparse(uint64_t seed, const char *str, MSize len)
 {
-#if 0
+#if !LJ_DS_STR_HASH_PATCH
   /* Constants taken from lookup3 hash by Bob Jenkins. */
   StrHash a, b, h = len ^ (StrHash)seed;
   if (len >= 4) {  /* Caveat: unaligned access! */
@@ -291,6 +291,9 @@ static GCstr *lj_str_alloc(lua_State *L, const char *str, MSize len,
   s->gct = ~LJ_TSTR;
   s->len = len;
   s->hash = hash;
+#if LJ_DS_STR_HASH_PATCH
+  s->sid = hash;
+#else
 #ifndef STRID_RESEED_INTERVAL
   s->sid = g->str.id++;
 #elif STRID_RESEED_INTERVAL
@@ -302,6 +305,7 @@ static GCstr *lj_str_alloc(lua_State *L, const char *str, MSize len,
   s->sid = g->str.id++;
 #else
   s->sid = (StrID)lj_prng_u64(&g->prng);
+#endif
 #endif
   s->reserved = 0;
   s->hashalg = (uint8_t)hashalg;
diff --git a/src/lj_tab.c b/src/lj_tab.c
index 568c0288..bc92bc16 100644
--- a/src/lj_tab.c
+++ b/src/lj_tab.c
@@ -374,6 +374,32 @@ void lj_tab_rehash(lua_State *L, GCtab *t)
 }
 #endif
 
+#if LJ_DS_PARSER_TABLE_PATCH
+void lj_tab_rehash_bykeys(lua_State *L, GCtab *t, GCtab *kt)
+{
+  Node *oldnode = noderef(t->node);
+  uint32_t oldhmask = t->hmask;
+  GCtab *tmp = lj_tab_new(L, t->asize, t->hmask > 0 ? lj_fls(t->hmask)+1 : 0);
+  for (size_t i = 0; i < kt->asize; i++)
+  {
+    TValue* k = arrayslot(kt, i);
+    if (tvisnil(k))
+      break;
+    cTValue* val = lj_tab_get(L, t, k);
+    TValue* tmp_v = lj_tab_set(L, tmp, k);
+    copyTV(L, tmp_v, val);
+  }
+  global_State *g = G(L);
+  Node* nilNode = &g->nilnode;
+  setmref(t->node, noderef(tmp->node));
+  setmref(t->freetop, noderef(tmp->freetop));
+  setmref(tmp->node, nilNode);
+  setmref(tmp->freetop, nilNode);
+  tmp->hmask = 0;
+  lj_mem_freevec(g, oldnode, oldhmask+1, Node);
+}
+#endif
+
 void lj_tab_reasize(lua_State *L, GCtab *t, uint32_t nasize)
 {
   lj_tab_resize(L, t, nasize+1, t->hmask > 0 ? lj_fls(t->hmask)+1 : 0);
diff --git a/src/lj_tab.h b/src/lj_tab.h
index 611959f5..2015de78 100644
--- a/src/lj_tab.h
+++ b/src/lj_tab.h
@@ -64,6 +64,9 @@ LJ_FUNC void LJ_FASTCALL lj_tab_free(global_State *g, GCtab *t);
 #if LJ_HASFFI
 LJ_FUNC void lj_tab_rehash(lua_State *L, GCtab *t);
 #endif
+#if LJ_DS_PARSER_TABLE_PATCH
+LJ_FUNC void lj_tab_rehash_bykeys(lua_State *L, GCtab *t, GCtab *kt);
+#endif
 LJ_FUNC void lj_tab_resize(lua_State *L, GCtab *t, uint32_t asize, uint32_t hbits);
 LJ_FUNCA void lj_tab_reasize(lua_State *L, GCtab *t, uint32_t nasize);