Feat/context #124

Job	Run time
android (-O0)	1m 13s
clang-linux (-O0)	3m 34s
clang-macosx (-O0)	1m 11s
clang-linux (-Ofast -flto -DNDEBUG)	3m 54s
clang-macosx (-O0 -stdlib=libc++, -stdlib=libc++)	56s
android (-Ofast -flto -DNDEBUG)	1m 56s
clang-linux (-Ofast -flto -DNDEBUG -stdlib=libc++, -stdlib=libc++)	4m 16s
gcc-linux (-O0)	3m 15s
clang-macosx (-Ofast -flto -DNDEBUG)	1m 12s
clang-linux (-O0 -stdlib=libc++, -stdlib=libc++)	3m 38s
gcc-linux (-Ofast -flto=auto -DNDEBUG)	3m 36s
clang-macosx (-Ofast -flto -DNDEBUG -stdlib=libc++, -stdlib=libc++)	1m 28s
gcc-macosx (-O0)	2m 23s
gcc-macosx (-Ofast -flto -DNDEBUG)	2m 32s
	35m 4s

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