Thread: pgsql: Replace xlc __fetch_and_add() with inline asm.

Replace xlc __fetch_and_add() with inline asm.

PostgreSQL has been unusable when built with xlc 13 and newer, which are
incompatible with our use of __fetch_and_add().  Back-patch to 9.5,
which introduced pg_atomic_fetch_add_u32().

Reviewed by Tom Lane.

Discussion: https://postgr.es/m/20190831071157.GA3251746@rfd.leadboat.com

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/8972ac69666550535a885aebe0930550c151b4a3

Modified Files
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src/include/port/atomics/generic-xlc.h | 39 ++++++++++++++++++++++++++++++----
1 file changed, 35 insertions(+), 4 deletions(-)