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| author | Paolo Carlini <paolo.carlini@oracle.com> | 2010-06-09 09:15:51 +0000 |
|---|---|---|
| committer | Paolo Carlini <paolo@gcc.gnu.org> | 2010-06-09 09:15:51 +0000 |
| commit | fa9d7d3b70bae40150022c469b6b50c001474e11 (patch) | |
| tree | 500559c8ddc05b9632615996c1a25949ffe8921d | |
| parent | a9f2ab18ba294528039486427c60e1bbf060c746 (diff) | |
| download | gcc-fa9d7d3b70bae40150022c469b6b50c001474e11.zip gcc-fa9d7d3b70bae40150022c469b6b50c001474e11.tar.gz gcc-fa9d7d3b70bae40150022c469b6b50c001474e11.tar.bz2 | |
re PR libstdc++/44413 (inefficient code for std::string::compare on x86-64)
2010-06-09 Paolo Carlini <paolo.carlini@oracle.com>
PR libstdc++/44413
* include/ext/vstring_util.h (__vstring_utility<>::_S_compare):
Simplify, just return -1, 0, 1.
From-SVN: r160456
| -rw-r--r-- | libstdc++-v3/ChangeLog | 6 | ||||
| -rw-r--r-- | libstdc++-v3/include/ext/vstring_util.h | 17 |
2 files changed, 12 insertions, 11 deletions
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index db2c206..edb1519 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,9 @@ +2010-06-09 Paolo Carlini <paolo.carlini@oracle.com> + + PR libstdc++/44413 + * include/ext/vstring_util.h (__vstring_utility<>::_S_compare): + Simplify, just return -1, 0, 1. + 2010-06-08 Paolo Carlini <paolo.carlini@oracle.com> * include/std/type_traits (has_nothrow_assign): Rename to diff --git a/libstdc++-v3/include/ext/vstring_util.h b/libstdc++-v3/include/ext/vstring_util.h index 4042f70..a9c88d4 100644 --- a/libstdc++-v3/include/ext/vstring_util.h +++ b/libstdc++-v3/include/ext/vstring_util.h @@ -1,6 +1,7 @@ // Versatile string utility -*- C++ -*- -// Copyright (C) 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc. +// Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 +// Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library is free // software; you can redistribute it and/or modify it under the @@ -50,10 +51,10 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) { typedef typename _Alloc::template rebind<_CharT>::other _CharT_alloc_type; - typedef _Traits traits_type; + typedef _Traits traits_type; typedef typename _Traits::char_type value_type; typedef typename _CharT_alloc_type::size_type size_type; - typedef typename _CharT_alloc_type::difference_type difference_type; + typedef typename _CharT_alloc_type::difference_type difference_type; typedef typename _CharT_alloc_type::pointer pointer; typedef typename _CharT_alloc_type::const_pointer const_pointer; @@ -164,14 +165,8 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) static int _S_compare(size_type __n1, size_type __n2) { - const difference_type __d = difference_type(__n1 - __n2); - - if (__d > __numeric_traits_integer<int>::__max) - return __numeric_traits_integer<int>::__max; - else if (__d < __numeric_traits_integer<int>::__min) - return __numeric_traits_integer<int>::__min; - else - return int(__d); + const difference_type __d = __n1 - __n2; + return __d == 0 ? 0 : (__d > 0 ? 1 : -1); } }; |