The approach of doing a recursive function call to expand the if checks
for known metadata names was tripping up an optimization clang has to
collapse that if/then tree into an optimized tree search over the set of
known strings. By unrolling that loop (with a code generator) we start
to present a pattern that clang *can* recognize, and hopefully get some
more stable and faster code generation as a benefit.
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Co-authored-by: ctiller <ctiller@users.noreply.github.com>
Craig Tiller