Commit Graph

13 Commits

Author SHA1 Message Date
Howard Hinnant
7a6b7cedcb Implement full support for non-pointer types in custom allocators. This is for the unordered containers only. This work still needs to be done on the sequence containers.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@184635 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-22 15:21:29 +00:00
Marshall Clow
83e2c4d877 Move common header files into a 'support' directory; make 'testit' include -I to that directory; rename 'iterators.h' to 'iterator_test.h'; remove hard-coded paths to include files from more than 350 source files
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@171594 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-05 03:21:01 +00:00
Marshall Clow
ba1920fe4b Removed several more different 'iterators.h' files in libcxx/test
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@171452 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-03 02:29:29 +00:00
Howard Hinnant
7a44515588 This commit establishes a new bucket_count policy in the unordered containers: The policy now allows a power-of-2 number of buckets to be requested (and that request honored) by the client. And if the number of buckets is set to a power of 2, then the constraint of the hash to the number of buckets uses & instead of %. If the client does not specify a number of buckets, then the policy remains unchanged: a prime number of buckets is selected. The growth policy is that the number of buckets is roughly doubled when needed. While growing, either the prime, or the power-of-2 strategy will be preserved. There is a small run time cost for putting in this switch. For very cheap hash functions, e.g. identity for int, the cost can be as high as 18%. However with more typical use cases, e.g. strings, the cost is in the noise level. I've measured cases with very cheap hash functions (int) that using a power-of-2 number of buckets can make look up about twice as fast. However I've also noted that a power-of-2 number of buckets is more susceptible to accidental catastrophic collisions. Though I've also noted that accidental catastrophic collisions are also possible when using a prime number of buckets (but seems far less likely). In short, this patch adds an extra tuning knob for those clients trying to get the last bit of performance squeezed out of their hash containers. Casual users of the hash containers will not notice the introduction of this tuning knob. Those clients who swear by power-of-2 hash containers can now opt-in to that strategy. Clients who prefer a prime number of buckets can continue as they have.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@159836 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-06 17:31:14 +00:00
Howard Hinnant
f836d531b4 unord test fixes by Edward Meewis
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@145707 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-02 21:23:14 +00:00
Howard Hinnant
e3e3291f3a Fixed PR10574: http://llvm.org/bugs/show_bug.cgi?id=10574
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@137522 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-12 21:56:02 +00:00
Howard Hinnant
04dae1df22 noexcept for <unordered_set>.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@132647 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-04 20:18:37 +00:00
Howard Hinnant
211f0ee1be Bug 9096 - list::iterator not default constructible
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@124508 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-28 23:46:28 +00:00
Howard Hinnant
b64f8b07c1 license change
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@119395 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-16 22:09:02 +00:00
Howard Hinnant
73d21a4f07 Changed __config to react to all of clang's currently documented has_feature flags, and renamed _LIBCPP_MOVE to _LIBCPP_HAS_NO_RVALUE_REFERENCES to be more consistent with the rest of the libc++'s flags, and with clang's nomenclature.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@113086 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-04 23:28:19 +00:00
Howard Hinnant
6046aced82 Fixing whitespace problems
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@111755 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-22 00:15:28 +00:00
Howard Hinnant
f5256e16df Wiped out some non-ascii characters that snuck into the copyright.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@103516 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-11 21:36:01 +00:00
Howard Hinnant
bc8d3f97eb libcxx initial import
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@103490 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-11 19:42:16 +00:00