Try to fix memory barriers on x86_64.
Try to fix memory barriers on x86_64.

%esp is no good; must use %rsp there.

techdragon/Postgres-XL,ovr/postgres-xl,jmcatamney/gpdb,lisakowen/gpdb,postmind-net/postgres-xl,adam8157/gpdb,jmcatamney/gpdb,50wu/gpdb,kmjungersen/PostgresXL,yazun/postgres-xl,ashwinstar/gpdb,yazun/postgres-xl,ashwinstar/gpdb,yazun/postgres-xl,lisakowen/gpdb,snaga/postgres-xl,kmjungersen/PostgresXL,50wu/gpdb,yazun/postgres-xl,snaga/postgres-xl,jmcatamney/gpdb,xinzweb/gpdb,adam8157/gpdb,Postgres-XL/Postgres-XL,xinzweb/gpdb,Postgres-XL/Postgres-XL,kmjungersen/PostgresXL,lisakowen/gpdb,postmind-net/postgres-xl,pavanvd/postgres-xl,xinzweb/gpdb,50wu/gpdb,jmcatamney/gpdb,pavanvd/postgres-xl,tpostgres-projects/tPostgres,snaga/postgres-xl,adam8157/gpdb,greenplum-db/gpdb,zeroae/postgres-xl,oberstet/postgres-xl,snaga/postgres-xl,50wu/gpdb,pavanvd/postgres-xl,tpostgres-projects/tPostgres,ovr/postgres-xl,xinzweb/gpdb,snaga/postgres-xl,ashwinstar/gpdb,lisakowen/gpdb,pavanvd/postgres-xl,zeroae/postgres-xl,greenplum-db/gpdb,arcivanov/postgres-xl,arcivanov/postgres-xl,ovr/postgres-xl,Postgres-XL/Postgres-XL,postmind-net/postgres-xl,ashwinstar/gpdb,lisakowen/gpdb,oberstet/postgres-xl,ovr/postgres-xl,postmind-net/postgres-xl,zeroae/postgres-xl,oberstet/postgres-xl,ashwinstar/gpdb,lisakowen/gpdb,techdragon/Postgres-XL,Postgres-XL/Postgres-XL,jmcatamney/gpdb,greenplum-db/gpdb,ashwinstar/gpdb,yazun/postgres-xl,xinzweb/gpdb,jmcatamney/gpdb,kmjungersen/PostgresXL,ashwinstar/gpdb,arcivanov/postgres-xl,arcivanov/postgres-xl,kmjungersen/PostgresXL,ovr/postgres-xl,adam8157/gpdb,greenplum-db/gpdb,lisakowen/gpdb,zeroae/postgres-xl,50wu/gpdb,xinzweb/gpdb,pavanvd/postgres-xl,greenplum-db/gpdb,techdragon/Postgres-XL,tpostgres-projects/tPostgres,ashwinstar/gpdb,greenplum-db/gpdb,jmcatamney/gpdb,techdragon/Postgres-XL,tpostgres-projects/tPostgres,xinzweb/gpdb,50wu/gpdb,Postgres-XL/Postgres-XL,postmind-net/postgres-xl,lisakowen/gpdb,50wu/gpdb,greenplum-db/gpdb,techdragon/Postgres-XL,adam8157/gpdb,tpostgres-projects/tPostgres,adam8157/gpdb,arcivanov/postgres-xl,adam8157/gpdb,oberstet/postgres-xl,xinzweb/gpdb,50wu/gpdb,zeroae/postgres-xl,arcivanov/postgres-xl,jmcatamney/gpdb,adam8157/gpdb,greenplum-db/gpdb,oberstet/postgres-xl