Vedant Kumar 78dfceef4b Retry: [llvm-profdata] Speed up merging by using a thread pool ... Add a "-j" option to llvm-profdata to control the number of threads used. Auto-detect NumThreads when it isn't specified, and avoid spawning threads when they wouldn't be beneficial. I tested this patch using a raw profile produced by clang (147MB). Here is the time taken to merge 4 copies together on my laptop: No thread pool: 112.87s user 5.92s system 97% cpu 2:01.08 total With 2 threads: 134.99s user 26.54s system 164% cpu 1:33.31 total Changes since the initial commit: - When handling odd-length inputs, call ThreadPool::wait() before merging the last profile. Should fix a race/off-by-one (see r275937). Differential Revision: https://reviews.llvm.org/D22438 llvm-svn: 275938		2016-07-19 01:17:20 +00:00
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llvm	Retry: [llvm-profdata] Speed up merging by using a thread pool	2016-07-19 01:17:20 +00:00
llvm-c	Do not use bool in C header lto.h, use lto_bool_t instead	2016-07-11 23:55:01 +00:00