Optimize size of ext/dom (#12830)

* Remove unused upper case tag static data

* Shrink size of static binary search tree

This also makes it more efficient on the data cache.

* Update patches

ext/dom/lexbor/lexbor/core/sbst.h

@@ -19,12 +19,12 @@ extern "C" {
 typedef struct {
     lxb_char_t key;
 
-    void       *value;
-    size_t     value_len;
+    lxb_char_t         value[6];
+    unsigned char      value_len;
 
-    size_t     left;
-    size_t     right;
-    size_t     next;
+    unsigned short     left;
+    unsigned short     right;
+    unsigned short     next;
 }
 lexbor_sbst_entry_static_t;
 

ext/dom/lexbor/lexbor/html/tokenizer/state.c

@@ -1815,7 +1815,7 @@ lxb_html_tokenizer_state_char_ref_named(lxb_html_tokenizer_t *tkz,
             goto done;
         }
 
-        if (entry->value != NULL) {
+        if (entry->value[0] != 0) {
             tkz->entity_end = (tkz->pos + (data - begin)) - tkz->start;
             tkz->entity_match = entry;
         }

ext/dom/lexbor/lexbor/tag/res.h

@@ -224,6 +224,7 @@ static const lxb_tag_data_t lxb_tag_res_data_default[LXB_TAG__LAST_ENTRY] =
     {{.u.short_str = "xmp", .length = 3, .next = NULL}, LXB_TAG_XMP, 1, true}
 };
 
+#if 0
 static const lxb_tag_data_t lxb_tag_res_data_upper_default[LXB_TAG__LAST_ENTRY] = 
 {
     {{.u.short_str = "#UNDEF", .length = 6, .next = NULL}, LXB_TAG__UNDEF, 1, true},
@@ -423,6 +424,7 @@ static const lxb_tag_data_t lxb_tag_res_data_upper_default[LXB_TAG__LAST_ENTRY]
     {{.u.short_str = "WBR", .length = 3, .next = NULL}, LXB_TAG_WBR, 1, true},
     {{.u.short_str = "XMP", .length = 3, .next = NULL}, LXB_TAG_XMP, 1, true}
 };
+#endif
 
 static const lexbor_shs_entry_t lxb_tag_res_shs_data_default[] = 
 {

ext/dom/lexbor/lexbor/tag/tag.c

@@ -92,6 +92,7 @@ lxb_tag_data_by_name(lexbor_hash_t *hash, const lxb_char_t *name, size_t len)
                                            lexbor_hash_search_lower, name, len);
 }
 
+#if 0
 const lxb_tag_data_t *
 lxb_tag_data_by_name_upper(lexbor_hash_t *hash,
                            const lxb_char_t *name, size_t len)
@@ -114,6 +115,7 @@ lxb_tag_data_by_name_upper(lexbor_hash_t *hash,
     return (const lxb_tag_data_t *) lexbor_hash_search(hash,
                                            lexbor_hash_search_upper, name, len);
 }
+#endif
 
 /*
  * No inline functions for ABI.

ext/dom/lexbor/patches/README.md

@@ -17,15 +17,23 @@ This contains the following patch files in mailbox format.
   A PHP specific patch to patch utilities and data structure to be able to generate smaller lookup tables.
   This patch won't be upstreamed because it breaks generality of those data structures, i.e. it only works
   because we only use it for character encoding.
+* 0001-Remove-unused-upper-case-tag-static-data.patch
+  A PHP specific patch to remove unused upper case tag static data. This shrinks the static data size.
+* 0001-Shrink-size-of-static-binary-search-tree.patch
+  A PHP specific patch to shrink the size of the static binary search tree for entities.
+  This shrinks the static data size and reduces data cache pressure.
 
   **Note** for this patch the utilities to generate the tables are also patched.
   Make sure to apply on a fresh Lexbor clone and run (in `lexbor/utils/encoding`): `python3 single-byte.py` and `python3 multi-byte.py` to generate the tables.
+  Also run `python3 tokenizer_entities_bst.py` to generate the static binary search tree for entities.
 
 ## How to apply
 
-* cd into `ext/dom/lexbor_bridge/lexbor`
+* cd into `ext/dom/lexbor/lexbor`
 * `git am -3 ../patches/0001-Expose-line-and-column-information-for-use-in-PHP.patch`
 * `git am -3 ../patches/0001-Track-implied-added-nodes-for-options-use-in-PHP.patch`
 * `git am -3 ../patches/0001-Patch-out-CSS-parser.patch`
 * `git am -3 ../patches/0001-Patch-utilities-and-data-structure-to-be-able-to-gen.patch`
-* `git reset HEAD~4` # 4 is the number of commits created by the above commands
+* `git am -3 ../patches/0001-Remove-unused-upper-case-tag-static-data.patch`
+* `git am -3 ../patches/0001-Shrink-size-of-static-binary-search-tree.patch`
+* `git reset HEAD~6` # 6 is the number of commits created by the above commands