swift234

Simple non-array binary search tree benchmark.

This includes a very simple pseudo-random number generator, which can
be used to drive benchmarks.

This doesn't include an official benchmark driver other than a trivial
test routine that generates the tree.

swift -emit-module -emit-library lfsr.swift -o liblfsr.dylib -O3
swift bst.swift -I. -L. -llfsr -O3

This is currently exposing an optimizer bug which will be filed shortly.

Swift SVN r17044