Reduce ExecSeqScan* code size using pg_assume() fb9f955025f optimized code generation by using specialized variants of ExecSeqScan* for [not] having a qual, projection etc. This allowed the compiler to optimize the code out the code for qual / projection. However, as observed by David Rowley at the time, the compiler couldn't prove the opposite, i.e. that the qual etc *are* present.
By using pg_assume(), introduced in d65eb5b1b84, we can tell the compiler that the relevant variables are non-null. This reduces the code size to a surprising degree and seems to lead to a small but reproducible performance gain. Reviewed-by: Amit Langote <amitlangot...@gmail.com> Discussion: https://postgr.es/m/CA+HiwqFk-MbwhfX_kucxzL8zLmjEt9MMcHi2YF=dyhprsjs...@mail.gmail.com Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/b227b0bb4e032e19b3679bedac820eba3ac0d1cf Modified Files -------------- src/backend/executor/nodeSeqscan.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
