perf(events): use hashy for event name lookup (#32802)

src/gen/gen_events.lua

@@ -1,6 +1,7 @@
 local fileio_enum_file = arg[1]
 local names_file = arg[2]
 
+local hashy = require('gen.hashy')
 local auevents = require('nvim.auevents')
 local events = auevents.events
 local aliases = auevents.aliases
@@ -41,9 +42,27 @@ for i, name in ipairs(names) do
 end
 
 enum_tgt:write(('\n  NUM_EVENTS = %u,'):format(#names))
-names_tgt:write('\n  [NUM_EVENTS] = {0, NULL, (event_T)0},\n};\n')
-names_tgt:write('\nstatic AutoCmdVec autocmds[NUM_EVENTS] = { 0 };\n')
-names_tgt:close()
-
 enum_tgt:write('\n} event_T;\n')
 enum_tgt:close()
+
+names_tgt:write('\n  [NUM_EVENTS] = {0, NULL, (event_T)0},\n};\n')
+names_tgt:write('\nstatic AutoCmdVec autocmds[NUM_EVENTS] = { 0 };\n')
+
+local hashorder = vim.tbl_map(string.lower, names)
+table.sort(hashorder)
+local hashfun
+hashorder, hashfun = hashy.hashy_hash('event_name2nr', hashorder, function(idx)
+  return 'event_names[event_hash[' .. idx .. ']].name'
+end, true)
+
+names_tgt:write([[
+
+static const event_T event_hash[] = {]])
+
+for _, lower_name in ipairs(hashorder) do
+  names_tgt:write(('\n  EVENT_%s,'):format(lower_name:upper()))
+end
+
+names_tgt:write('\n};\n\n')
+names_tgt:write('static ' .. hashfun)
+names_tgt:close()

src/nvim/CMakeLists.txt

@@ -677,7 +677,7 @@ add_custom_command(OUTPUT ${GENERATED_FUNCS} ${FUNCS_DATA}
 
 add_custom_command(OUTPUT ${GENERATED_EVENTS_ENUM} ${GENERATED_EVENTS_NAMES_MAP}
   COMMAND ${LUA_GEN} ${EVENTS_GENERATOR} ${GENERATED_EVENTS_ENUM} ${GENERATED_EVENTS_NAMES_MAP}
-  DEPENDS ${LUA_GEN_DEPS} ${EVENTS_GENERATOR} ${CMAKE_CURRENT_LIST_DIR}/auevents.lua
+  DEPENDS ${LUA_GEN_DEPS} ${EVENTS_GENERATOR} ${GENERATOR_HASHY} ${CMAKE_CURRENT_LIST_DIR}/auevents.lua
 )
 
 add_custom_command(OUTPUT ${GENERATED_KEYCODE_NAMES}

src/nvim/autocmd.c

@@ -618,36 +618,30 @@ bool is_aucmd_win(win_T *win)
 event_T event_name2nr(const char *start, char **end)
 {
   const char *p;
-  int i;
 
   // the event name ends with end of line, '|', a blank or a comma
   for (p = start; *p && !ascii_iswhite(*p) && *p != ',' && *p != '|'; p++) {}
-  for (i = 0; event_names[i].name != NULL; i++) {
+
-    int len = (int)event_names[i].len;
+  int hash_idx = event_name2nr_hash(start, (size_t)(p - start));
-    if (len == p - start && STRNICMP(event_names[i].name, start, len) == 0) {
-      break;
-    }
-  }
   if (*p == ',') {
     p++;
   }
   *end = (char *)p;
-  if (event_names[i].name == NULL) {
+  if (hash_idx < 0) {
     return NUM_EVENTS;
   }
-  return (event_T)abs(event_names[i].event);
+  return (event_T)abs(event_names[event_hash[hash_idx]].event);
 }
 
 /// Return the event number for event name "str".
 /// Return NUM_EVENTS if the event name was not found.
 event_T event_name2nr_str(String str)
 {
-  for (int i = 0; event_names[i].name != NULL; i++) {
+  int hash_idx = event_name2nr_hash(str.data, str.size);
-    if (str.size == event_names[i].len && STRNICMP(str.data, event_names[i].name, str.size) == 0) {
+  if (hash_idx < 0) {
-      return (event_T)abs(event_names[i].event);
+    return NUM_EVENTS;
-    }
   }
-  return NUM_EVENTS;
+  return (event_T)abs(event_names[event_hash[hash_idx]].event);
 }
 
 /// Return the name for event