Starting using murmur2 when combining multiple size_t's into a single hash, and also for basic_string. Also made hash<thread::id> ever so slighly more portable. I had to tweak one test which is questionable (definitely not portable) anyway.
llvm-svn: 145795
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: f3d14a65ca0bc0e4f7548eb643d5e55e59429b1e
diff --git a/include/string b/include/string
index 575b9e1..4457e4a 100644
--- a/include/string
+++ b/include/string
@@ -3915,16 +3915,8 @@
template<class _Ptr>
size_t _LIBCPP_INLINE_VISIBILITY __do_string_hash(_Ptr __p, _Ptr __e)
{
- size_t __r = 0;
- const size_t __sr = __CHAR_BIT__ * sizeof(size_t) - 8;
- const size_t __m = size_t(0xF) << (__sr + 4);
- for (; __p != __e; ++__p)
- {
- __r = (__r << 4) + *__p;
- size_t __g = __r & __m;
- __r ^= __g | (__g >> __sr);
- }
- return __r;
+ typedef typename iterator_traits<_Ptr>::value_type value_type;
+ return __murmur2<size_t>()(__p, (__e-__p)*sizeof(value_type));
}
template<class _CharT, class _Traits, class _Allocator>