libstdc++/regex: add [[gnu::always_inline]] to _Executor::_M_node

The compiler understandably doesn't know that _M_node only ever has a
single call site, _M_dfs, (and is not directly called from other library
headers or user code) and so decides not to inline it.  So use the
always_inline attribute to force the inlining.  This seems sufficient to
make all _M_dfs subroutines get inlined away, and speeds up the executor
by 30% on some microbenchmarks.

libstdc++-v3/ChangeLog:

	* include/bits/regex_executor.tcc (__detail::_Executor::_M_node)
	[__OPTIMIZE__]: Add [[gnu::always_inline]] attribute.  Declare
	inline.

Reviewed-by: Jonathan Wakely <jwakely@redhat.com>

0 files changed, 0 insertions, 0 deletions