Chandler Carruth 1501b6be37 Introduce a SmallDenseMap container that re-uses the existing DenseMap ... implementation. This type includes an inline bucket array which is used initially. Once it is exceeded, an array of 64 buckets is allocated on the heap. The bucket count grows from there as needed. Some highlights of this implementation: - The inline buffer is very carefully aligned, and so supports types with alignment constraints. - It works hard to avoid aliasing issues. - Supports types with non-trivial constructors, destructors, copy constructions, etc. It works reasonably hard to minimize copies and unnecessary initialization. The most common initialization is to set keys to the empty key, and so that should be fast if at all possible. This class has a performance / space trade-off. It tries to optimize for relatively small maps, and so packs the inline bucket array densely into the object. It will be marginally slower than a normal DenseMap in a few use patterns, so it isn't appropriate everywhere. The unit tests for DenseMap have been generalized a bit to support running over different map implementations in addition to different key/value types. They've then been automatically extended to cover the new container through the magic of GoogleTest's typed tests. All of this is still a bit rough though. I'm going to be cleaning up some aspects of the implementation, documenting things better, and adding tests which include non-trivial types. As soon as I'm comfortable with the correctness, I plan to switch existing users of SmallMap over to this class as it is already more correct w.r.t. construction and destruction of objects iin the map. Thanks to Benjamin Kramer for all the reviews of this and the lead-up patches. That said, more review on this would really be appreciated. As I've noted a few times, I'm quite surprised how hard it is to get the semantics for a hashtable-based map container with a small buffer optimization correct. =] llvm-svn: 158638		2012-06-17 09:05:09 +00:00
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ADT	Introduce a SmallDenseMap container that re-uses the existing DenseMap	2012-06-17 09:05:09 +00:00
Analysis	The product of two chrec's can always be represented as a chrec.	2011-10-04 06:51:26 +00:00
Bitcode	Bitcode: Don't expose WriteBitcodeToStream to clients.	2012-02-29 20:30:56 +00:00
ExecutionEngine	Disable JITTest.FunctionIsRecompiledAndRelinked and JITTest.NoStubs	2012-05-16 19:07:55 +00:00
Support	Add some somewhat exhaustive tests of sizeof properties of this horrible	2012-06-17 09:05:04 +00:00
Transforms	Unweaken vtables as per http://llvm.org/docs/CodingStandards.html#ll_virtual_anch	2011-12-20 02:50:00 +00:00
VMCore	Fix typos found by http://github.com/lyda/misspell-check	2012-06-02 10:20:22 +00:00
CMakeLists.txt	Update CMake build.	2012-06-16 10:53:58 +00:00
Makefile	Undo the hack in r147427 and move this unittest to a better home. This	2012-01-02 09:19:48 +00:00
Makefile.unittest	build/unittests: Fix llvm-config names for gtest libraries, and bring Makefile	2011-12-15 23:35:08 +00:00