diff --git a/sqlparse/engine/grouping.py b/sqlparse/engine/grouping.py
index d8cfa9e1..951667d7 100644
--- a/sqlparse/engine/grouping.py
+++ b/sqlparse/engine/grouping.py
@@ -41,6 +41,7 @@ def _group_matching(tlist, cls, depth=0):
     opens = []
     tidx_offset = 0
     token_list = list(tlist)
+    m_open, m_close = cls.M_OPEN, cls.M_CLOSE
 
     for idx, token in enumerate(token_list):
         tidx = idx - tidx_offset
@@ -58,10 +59,10 @@ def _group_matching(tlist, cls, depth=0):
             _group_matching(token, cls, depth + 1)
             continue
 
-        if token.match(*cls.M_OPEN):
+        if token.match(*m_open):
             opens.append(tidx)
 
-        elif token.match(*cls.M_CLOSE):
+        elif token.match(*m_close):
             try:
                 open_idx = opens.pop()
             except IndexError:
@@ -382,11 +383,12 @@ def group_functions(tlist):
     has_table = False
     has_as = False
     for tmp_token in tlist.tokens:
-        if tmp_token.value.upper() == 'CREATE':
+        value = tmp_token.value.upper()
+        if value == 'CREATE':
             has_create = True
-        if tmp_token.value.upper() == 'TABLE':
+        elif value == 'TABLE':
             has_table = True
-        if tmp_token.value.upper() == 'AS':
+        elif value == 'AS':
             has_as = True
     if has_create and has_table and not has_as:
         return
diff --git a/sqlparse/sql.py b/sqlparse/sql.py
index ec44a6da..8d669526 100644
--- a/sqlparse/sql.py
+++ b/sqlparse/sql.py
@@ -39,6 +39,11 @@ def get_alias(self):
             return self._get_first_name(reverse=True)
 
 
+#: ``(is_keyword, is_whitespace, is_newline)`` per token type.  Snapshotted at
+#: construction, as before: grouping reassigns ``ttype`` without revisiting it.
+_TTYPE_FLAGS = {}
+
+
 class Token:
     """Base class for all other classes in this module.
 
@@ -64,9 +69,11 @@ def __init__(self, ttype, value):
         self.ttype = ttype
         self.parent = None
         self.is_group = False
-        self.is_keyword = ttype in T.Keyword
-        self.is_whitespace = self.ttype in T.Whitespace
-        self.is_newline = self.ttype in T.Newline
+        flags = _TTYPE_FLAGS.get(ttype)
+        if flags is None:
+            flags = _TTYPE_FLAGS[ttype] = (
+                ttype in T.Keyword, ttype in T.Whitespace, ttype in T.Newline)
+        self.is_keyword, self.is_whitespace, self.is_newline = flags
         self.normalized = value.upper() if self.is_keyword else value
 
     def __str__(self):
@@ -270,8 +277,14 @@ def matcher(tk):
         return self._token_matching(matcher)[1]
 
     def token_next_by(self, i=None, m=None, t=None, idx=-1, end=None):
-        idx += 1
-        return self._token_matching(lambda tk: imt(tk, i, m, t), idx, end)
+        # Not routed through _token_matching: its lambda cost two Python calls
+        # per token, and every grouping pass walks the tree through here.
+        tokens = self.tokens
+        for tidx in range(idx + 1, len(tokens) if end is None else end):
+            token = tokens[tidx]
+            if imt(token, i, m, t):
+                return tidx, token
+        return None, None
 
     def token_not_matching(self, funcs, idx):
         funcs = (funcs,) if not isinstance(funcs, (list, tuple)) else funcs