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author | Benjamin Kramer <benny.kra@googlemail.com> | 2010-08-23 18:16:08 +0000 |
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committer | Benjamin Kramer <benny.kra@googlemail.com> | 2010-08-23 18:16:08 +0000 |
commit | 250eb005d91e80b05a61345394bae9e9528151ac (patch) | |
tree | c58d7c38b1b4ffebf842dac455d0ccd72fc251e0 /include | |
parent | 0e2c359a3e57e934d93298f1c666241ed0d481ee (diff) | |
download | llvm-250eb005d91e80b05a61345394bae9e9528151ac.tar.gz llvm-250eb005d91e80b05a61345394bae9e9528151ac.tar.bz2 llvm-250eb005d91e80b05a61345394bae9e9528151ac.tar.xz |
Avoid O(n*m) complexity in StringRef::find_first(_not)_of(StringRef).
- Cache used characters in a bitset to reduce memory overhead to just 32 bytes.
- On my core2 this code is faster except when the checked string was very short
(smaller than the list of delimiters).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111817 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'include')
-rw-r--r-- | include/llvm/ADT/StringRef.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/llvm/ADT/StringRef.h b/include/llvm/ADT/StringRef.h index a1be1e70c2..8386d3ee42 100644 --- a/include/llvm/ADT/StringRef.h +++ b/include/llvm/ADT/StringRef.h @@ -238,7 +238,7 @@ namespace llvm { /// find_first_of - Find the first character in the string that is in \arg /// Chars, or npos if not found. /// - /// Note: O(size() * Chars.size()) + /// Note: O(size() + Chars.size()) size_type find_first_of(StringRef Chars, size_t From = 0) const; /// find_first_not_of - Find the first character in the string that is not @@ -248,7 +248,7 @@ namespace llvm { /// find_first_not_of - Find the first character in the string that is not /// in the string \arg Chars, or npos if not found. /// - /// Note: O(size() * Chars.size()) + /// Note: O(size() + Chars.size()) size_type find_first_not_of(StringRef Chars, size_t From = 0) const; /// @} |