Use a perfect hash map for the registry controlled domain service.

On my very fast machine, building the std::set in release mode on startup and blocks the UI thread for 15ms (there are > 3300 entries).  It also uses 275KB of memory, not including 50KB of data in the dll.  Using a perfect hash map, there's no startup cost.  The dll's size increases by 135KB but there's no extra memory consumption, leading to a memory reduction of 140KB.

Review URL: http://codereview.chromium.org/515001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@35196 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 155 insertions, 0 deletions

diff --git a/net/base/effective_tld_names_unittest2.cc b/net/base/effective_tld_names_unittest2.cc
new file mode 100644
index 0000000..8dcd448
--- /dev/null
+++ b/net/base/effective_tld_names_unittest2.cc
@@ -0,0 +1,155 @@
+/* C++ code produced by gperf version 3.0.3 */
+/* Command-line: gperf -a -L C++ -C -c -o -t -k '*' -NFindDomain -ZPerfect_Hash_Test2 -D effective_tld_names_unittest2.gperf  */
+
+#if !((' ' == 32) && ('!' == 33) && ('"' == 34) && ('#' == 35) \
+      && ('%' == 37) && ('&' == 38) && ('\'' == 39) && ('(' == 40) \
+      && (')' == 41) && ('*' == 42) && ('+' == 43) && (',' == 44) \
+      && ('-' == 45) && ('.' == 46) && ('/' == 47) && ('0' == 48) \
+      && ('1' == 49) && ('2' == 50) && ('3' == 51) && ('4' == 52) \
+      && ('5' == 53) && ('6' == 54) && ('7' == 55) && ('8' == 56) \
+      && ('9' == 57) && (':' == 58) && (';' == 59) && ('<' == 60) \
+      && ('=' == 61) && ('>' == 62) && ('?' == 63) && ('A' == 65) \
+      && ('B' == 66) && ('C' == 67) && ('D' == 68) && ('E' == 69) \
+      && ('F' == 70) && ('G' == 71) && ('H' == 72) && ('I' == 73) \
+      && ('J' == 74) && ('K' == 75) && ('L' == 76) && ('M' == 77) \
+      && ('N' == 78) && ('O' == 79) && ('P' == 80) && ('Q' == 81) \
+      && ('R' == 82) && ('S' == 83) && ('T' == 84) && ('U' == 85) \
+      && ('V' == 86) && ('W' == 87) && ('X' == 88) && ('Y' == 89) \
+      && ('Z' == 90) && ('[' == 91) && ('\\' == 92) && (']' == 93) \
+      && ('^' == 94) && ('_' == 95) && ('a' == 97) && ('b' == 98) \
+      && ('c' == 99) && ('d' == 100) && ('e' == 101) && ('f' == 102) \
+      && ('g' == 103) && ('h' == 104) && ('i' == 105) && ('j' == 106) \
+      && ('k' == 107) && ('l' == 108) && ('m' == 109) && ('n' == 110) \
+      && ('o' == 111) && ('p' == 112) && ('q' == 113) && ('r' == 114) \
+      && ('s' == 115) && ('t' == 116) && ('u' == 117) && ('v' == 118) \
+      && ('w' == 119) && ('x' == 120) && ('y' == 121) && ('z' == 122) \
+      && ('{' == 123) && ('|' == 124) && ('}' == 125) && ('~' == 126))
+/* The character set is not based on ISO-646.  */
+#error "gperf generated tables don't work with this execution character set. Please report a bug to <bug-gnu-gperf@gnu.org>."
+#endif
+
+#line 1 "effective_tld_names_unittest2.gperf"
+
+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that
+// can be found in the LICENSE file.
+// Test file used by registry_controlled_domain_unittest.
+// We edit this file manually, then run
+// gperf -a -L "C++" -C -c -o -t -k '*' -NFindDomain -ZPerfect_Hash_Test2 -D effective_tld_names_unittest2.gperf >  effective_tld_names_unittest2.cc
+// to generate the perfect hashmap.
+#line 10 "effective_tld_names_unittest2.gperf"
+struct DomainRule {
+  const char *name;
+  int type;  // 1: exception, 2: wildcard
+};
+
+#define TOTAL_KEYWORDS 2
+#define MIN_WORD_LENGTH 2
+#define MAX_WORD_LENGTH 6
+#define MIN_HASH_VALUE 2
+#define MAX_HASH_VALUE 6
+/* maximum key range = 5, duplicates = 0 */
+
+class Perfect_Hash_Test2
+{
+private:
+  static inline unsigned int hash (const char *str, unsigned int len);
+public:
+  static const struct DomainRule *FindDomain (const char *str, unsigned int len);
+};
+
+inline unsigned int
+Perfect_Hash_Test2::hash (register const char *str, register unsigned int len)
+{
+  static const unsigned char asso_values[] =
+    {
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 0, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 0, 0, 7,
+      7, 7, 7, 7, 7, 7, 0, 7, 7, 7,
+      7, 7, 0, 7, 0, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+      7, 7, 7, 7, 7, 7
+    };
+  register int hval = len;
+
+  switch (hval)
+    {
+      default:
+        hval += asso_values[(unsigned char)str[5]];
+      /*FALLTHROUGH*/
+      case 5:
+        hval += asso_values[(unsigned char)str[4]];
+      /*FALLTHROUGH*/
+      case 4:
+        hval += asso_values[(unsigned char)str[3]];
+      /*FALLTHROUGH*/
+      case 3:
+        hval += asso_values[(unsigned char)str[2]];
+      /*FALLTHROUGH*/
+      case 2:
+        hval += asso_values[(unsigned char)str[1]];
+      /*FALLTHROUGH*/
+      case 1:
+        hval += asso_values[(unsigned char)str[0]];
+        break;
+    }
+  return hval;
+}
+
+const struct DomainRule *
+Perfect_Hash_Test2::FindDomain (register const char *str, register unsigned int len)
+{
+  static const struct DomainRule wordlist[] =
+    {
+#line 15 "effective_tld_names_unittest2.gperf"
+      {"jp", 0},
+#line 16 "effective_tld_names_unittest2.gperf"
+      {"bar.jp", 0}
+    };
+
+  static const signed char lookup[] =
+    {
+      -1, -1,  0, -1, -1, -1,  1
+    };
+
+  if (len <= MAX_WORD_LENGTH && len >= MIN_WORD_LENGTH)
+    {
+      register int key = hash (str, len);
+
+      if (key <= MAX_HASH_VALUE && key >= 0)
+        {
+          register int index = lookup[key];
+
+          if (index >= 0)
+            {
+              register const char *s = wordlist[index].name;
+
+              if (*str == *s && !strncmp (str + 1, s + 1, len - 1) && s[len] == '\0')
+                return &wordlist[index];
+            }
+        }
+    }
+  return 0;
+}
+#line 17 "effective_tld_names_unittest2.gperf"
+