pgsql: Inline the fast path of plpgsql's exec_cast_value().

Inline the fast path of plpgsql's exec_cast_value().

In the common case where this function isn't actually asked to perform
any type conversion, there's nothing it has to do beyond comparing the
arguments.  Arrange for that part to be inlined into callers, with the
slower path remaining out-of-line.  This seems to be good for several
percent speedup on simple cases, with only minimal code bloat.

Amit Khandekar

Discussion: https://postgr.es/m/CAJ3gD9eBNrmUD7WBBLG8ohaZ485H9y+4eihQTgr+K8Lhka3vcQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/fe2e206cdb00a2d5dcebc3c8e8119017392d9781

Modified Files
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src/pl/plpgsql/src/pl_exec.c | 65 +++++++++++++++++++++++++++++---------------
1 file changed, 43 insertions(+), 22 deletions(-)