pgsql: Add pg_attribute_always_inline.

Add pg_attribute_always_inline.

Sometimes it is useful to be able to insist that the compiler inline a
function that its normal cost analysis would not normally choose to inline.
This can be useful for instantiating different variants of a function that
remove branches of code by constant folding.

Author: Thomas Munro
Reviewed-By: Andres Freund
Discussion: https://postgr.es/m/CAEepm=09rr65VN+cAV5FgyM_z=D77Xy8Fuc9CDDDYbq3pQUezg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dbb3d6f0102e0aca7575ff864450fca57ac85517

Modified Files
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src/include/c.h | 10 ++++++++++
1 file changed, 10 insertions(+)